@article{SchartlKneitzWildeetal.2012,
author = {Schartl, Manfred and Kneitz, Susanne and Wilde, Brigitta and Wagner, Toni and Henkel, Christiaan V. and Spaink, Hermann P. and Meierjohann, Svenja},
title = {Conserved expression signatures between medaka and human pigment cell tumors},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75848},
year = {2012},
abstract = {Aberrations in gene expression are a hallmark of cancer cells. Differential tumor-specific transcript levels of single genes or whole sets of genes may be critical for the neoplastic phenotype and important for therapeutic considerations or useful as biomarkers. As an approach to filter out such relevant expression differences from the plethora of changes noted in global expression profiling studies, we searched for changes of gene expression levels that are conserved. Transcriptomes from massive parallel sequencing of different types of melanoma from medaka were generated and compared to microarray datasets from zebrafish and human melanoma. This revealed molecular conservation at various levels between fish models and human tumors providing a useful strategy for identifying expression signatures strongly associated with disease phenotypes and uncovering new melanoma molecules.},
subject = {Biologie},
language = {en}
}
@article{SchmuckKobeltLinsenmair1988,
author = {Schmuck, R. and Kobelt, F. and Linsenmair, Karl Eduard},
title = {Adaptations of the reed frog Hyperbolius viridiflavus (Anura, Hyperbolidae) to its arid environment: V. Iridophores and nitrogen metabolism},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-78094},
year = {1988},
abstract = {Ofall amphibians living in arid habitats, reed frogs (belonging to the super species Hyperolius viridiflavus) are the most peculiar. Froglets are able to tolerate dry periods of up to 35 days or longer immediately after metamorphosis, in climatically exposed positions. They face similar problems to estivating juveniles, i.e. enduranee of long periods of high temperature and low RH with rather limited energy and water reserves. In addition, they must have had to develop meehanisms to prevent poisoning by nitrogenous wastes that rapidly accumulate during dry periods as a metabolie consequenee of maintaining a non-torpid state. During dry periods, plasma osmolarity of H. v. taeniatus froglets strongly increased, mainly through urea accumulation. Urea accumulation was also observed during metamorphic climax. During postmetamorphic growth, chromatophores develop with the density and morphology typical of the adult pigmentary pattern. The dermal iridophore layer, which is still incomplete at this time, is fully developed within 4-8 days after metamorphosis, irrespective of maintenance conditions. These iridophores mainly contain the purines guanine and hypoxanthine. The ability of these purines to reflect light provides an excellent basis for the role of iridophores in temperature regulation. In individuals experiencing dehydration stress, the initial rate of purine synthesis is doubled in eomparison to specimens continuously maintained under wet season conditions. This increase in synthesis rate leads to a rapid increase in the thiekness of the iridophore layer, thereby effectively reducing radiation absorption. Thus, the danger of overheating is diminished during periods of water shortage when evaporative cooling must be avoided. After the development of an iridophore layer of sufficient thickness for effective radiation reflectance, synthesis of iridophore pigments does not cease. Rather, this pathway is further used during the remaining dry season for solving osmotic problems eaused by accumulation of nitrogenous wastes. During prolonged water deprivation, in spite of reduced metabolic rates, purine pigments are produced at the same rate as in wet season conditions. This leads to a higher relative proportion of nitrogen end products being stored in skin pigments under dry season conditions. At the end of an experimental dry season lasting 35 days, up to 38\% of the accrued nitrogen is stored in the form of osmotically inactive purines in thc skin. Thus the osmotic problems caused by evaporative water loss and urea production are greatly reduced.},
subject = {Biologie},
language = {en}
}
@article{SchneiderSchauliesLiebertBaczkoetal.1988,
author = {Schneider-Schaulies, Sibylle and Liebert, UG and Baczko, K. and ter Meulen, V.},
title = {Molecular Biological Aspects of Virus-Induced Subacute Encephalomyelitis in Lewis Rats},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-81776},
year = {1988},
abstract = {no abstract available},
subject = {Biologie},
language = {en}
}
@article{SchueleinKreftGonskietal.1991,
author = {Sch{\"u}lein, Ralf and Kreft, J{\"u}rgen and Gonski, Sigrid and Goebel, Werner},
title = {Preprosubtilisin Carlsberg processing and secretion is blocked after deletion of amino acids 97-101 in the mature part of the enzyme},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-60577},
year = {1991},
abstract = {During an investigation into the substrate specificity and processing of subtilisin Carlsberg from Bacillus licheniformis, two major independent findings were made: (i) as has been shown previously, a stretch of five amino acids (residues 97-101 of the mature enzyme) that loops out into the binding cleft is involved in substrate binding by subtilisin Carlsberg. In order to see whether this loop element also determines substrate specificity, the coding region for these five amino acids was deleted from the cloned gene for subtilisin Carlsberg by site-directed mutagenesis. Unexpectedly the resulting mutant preproenzyme (P42c, Mr=42 kDa) was not processed to the mature form (Mr = 30 kDa) and was not released into the medium by a proteasedeficient B. subtilis host strain; rather, it accumulated in the cell membrane. This result demonstrates that the integrity of this loop element, which is very distant from the processing cleavage sites in the preproenzyme, is required for secretion of subtilisin Carlsberg. (ii) In culture supernatants from B. subtilis harbouring the cloned wild-type subtilisin Carlsberg gene the transient appearance (at 0-3 h after onset of stationary phase) of a processing intermediate (P38c, Mr = 38 kDa) oftbis protease could be demonstrated. P38c very probably represents a genuine proform of subtilisin Carlsberg.},
subject = {Biologie},
language = {en}
}
@phdthesis{Segebarth2021,
author = {Segebarth, Dennis},
title = {Evaluation and validation of deep learning strategies for bioimage analyses},
doi = {10.25972/OPUS-24372},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-243728},
school = {Universit{\"a}t W{\"u}rzburg},
year = {2021},
abstract = {Significant advances in fluorescence imaging techniques enable life scientists today to gain insights into biological systems at an unprecedented scale. The interpretation of image features in such bioimage datasets and their subsequent quantitative analysis is referred to as bioimage analysis. A substantial proportion of bioimage analyses is still performed manually by a human expert - a tedious process that is long known to be subjective. Particularly in tasks that require the annotation of image features with a low signal-to-noise ratio, like in fluorescence images of tissue samples, the inter-rater agreement drops. However, like any other scientific analysis, also bioimage analysis has to meet the general quality criteria of quantitative research, which are objectivity, reliability, and validity. Thus, the automation of bioimage analysis with computer-aided approaches is highly desirable. Albeit conventional hard-coded algorithms are fully unbiased, a human user has to set its respective feature extraction parameters. Thus, also these approaches can be considered subjective. Recently, deep learning (DL) has enabled impressive advances in computer vision research. The predominant difference between DL and conventional algorithms is the capability of DL models to learn the respective task on base of an annotated training dataset, instead of following user-defined rules for feature extraction. This thesis hypothesized that DL can be used to increase the objectivity, reliability, and validity of bioimage analyses, thus going beyond mere automation. However, in absence of ground truth annotations, DL models have to be trained on manual and thus subjective annotations, which could cause the model to incorporate such a bias. Moreover, model training is stochastic and even training on the same data could result in models with divergent outputs. Consequently, both the training on subjective annotations and the model-to-model variability could impair the quality of DL-based bioimage analyses. This thesis systematically assessed the impacts of these two limitations experimentally by analyzing fluorescence signals of a protein called cFOS in mouse brain sections. Since the abundance of cFOS correlates with mouse behavior, behavioral analyses could be used for cross-validation of the bioimage analysis results. Furthermore, this thesis showed that pooling the input of multiple human experts during model training and integration of multiple trained models in a model ensemble can mitigate the impact of these limitations. In summary, the present study establishes guidelines for how DL can be used to increase the general quality of bioimage analyses.},
subject = {Deeplearning},
language = {en}
}
@article{SturmHessWeibeletal.2012,
author = {Sturm, Julia B. and Hess, Michael and Weibel, Stephanie and Chen, Nanhei G. and Yu, Yong A. and Zhang, Quian and Donat, Ulrike and Reiss, Cora and Gambaryan, Stepan and Krohne, Georg and Stritzker, Jochen and Szalay, Aladar A.},
title = {Functional hyper-IL-6 from vaccinia virus-colonized tumors triggers platelet formation and helps to alleviate toxicity of mitomycin C enhanced virus therapy},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75224},
year = {2012},
abstract = {Background: Combination of oncolytic vaccinia virus therapy with conventional chemotherapy has shown promise for tumor therapy. However, side effects of chemotherapy including thrombocytopenia, still remain problematic. Methods: Here, we describe a novel approach to optimize combination therapy of oncolytic virus and chemotherapy utilizing virus-encoding hyper-IL-6, GLV-1h90, to reduce chemotherapy-associated side effects. Results: We showed that the hyper-IL-6 cytokine was successfully produced by GLV-1h90 and was functional both in cell culture as well as in tumor-bearing animals, in which the cytokine-producing vaccinia virus strain was well tolerated. When combined with the chemotherapeutic mitomycin C, the anti-tumor effect of the oncolytic virotherapy was significantly enhanced. Moreover, hyper-IL-6 expression greatly reduced the time interval during which the mice suffered from chemotherapy-induced thrombocytopenia. Conclusion: Therefore, future clinical application would benefit from careful investigation of additional cytokine treatment to reduce chemotherapy-induced side effects.},
subject = {Biologie},
language = {en}
}
@article{WehnerWeisteDroegeLaser2011,
author = {Wehner, Nora and Weiste, Christoph and Dr{\"o}ge-Laser, Wolfgang},
title = {Molecular screening tools to study Arabidopsis transcription factors},
url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69226},
year = {2011},
abstract = {In the model plant Arabidopsis thaliana, more than 2000 genes are estimated to encode transcription factors (TFs), which clearly emphasizes the importance of transcriptional control. Although genomic approaches have generated large TF open reading frame (ORF) collections, only a limited number of these genes is functionally characterized, yet. This review evaluates strategies and methods to identify TF functions. In particular, we focus on two recently developed TF screening platforms, which make use of publically available GATEWAY®-compatible ORF collections. (1) The Arabidopsis thaliana TF ORF over-Expression (AtTORF-Ex) library provides pooled collections of transgenic lines over-expressing HA-tagged TF genes, which are suited for screening approaches to define TF functions in stress defense and development. (2) A high-throughput microtiter plate based protoplast trans activation (PTA) system has been established to screen for TFs which are regulating a given promoter:Luciferase construct in planta.},
subject = {Biologie},
language = {en}
}