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Processing and Visualization of Mass Spectrums
Beneš, Ondřej ; Bendl, Jaroslav (referee) ; Martínek, Tomáš (advisor)
One of new techniques in the field of analytical chemistry, which has more and more practical use, is mass spectrometry imaging. With its ability to record representation of substances in samples during the tissue analyze arise problem with a lot of output data which needs to be handled programmatically. The goal of this work is to create an software for processing and visualization data of new standard imzML. As a part of the work, the field of mass spectrometry, primarily MALDI TOF mass spectrometry, is briefly introduced. There are also introduced some methods for mass spectrometry data preprocessing. The work also contains a summary of current state of available software for processing and visualization of mass spectrometry data. With requests from cooperating laboratory a novel software is designed and implemented, which besides the visualization itself, can preprocess the data for example data smoothing with Savitzky-Golay method, internal calibration or peak detection with continuous wavelet transformation. The software was successfully tested on real data sets.
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Prediction of Protein Stability upon Mutations Using Evolution Strategy
Pavlík, David ; Martínek, Tomáš (referee) ; Bendl, Jaroslav (advisor)
This master's thesis deals with the matter of predicting the effects of aminoacid substitutions on protein stability. The main aim is to design meta-classifier that combines the results of the selected prediction tools. An evolution strategy was used to find the best weights for each of the selected tools with the aim of achieving better prediction performance compared to that achieved by using these tools separately. Five different and obtainable prediction tools were selected and their prediction outputs were weighted. Two different approaches of evolution strategy are investigated and compared: evolution strategy with the 1/5-rule and evolution strategy with the type 2 of control parameters self-adaptation. Two independent datasets of mutations were created for training and evaluating the performance of designed meta-classifier. The performed experiments and obtained results suggest that the evolution strategy could be considered as a~beneficial approach for prediction of protein stability changes. However, the special attention must be paid to careful selection of tools for integration and compilation of training and testing datasets.
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Visualization of Transposons' Genomic Features
Nétková, Barbora ; Bendl, Jaroslav (referee) ; Vogel, Ivan (advisor)
This thesis deals with visualization of transposons' genomic features. The Genomic feature format (GFF) is an input file to visualisation. This type of file has strict definition and it is nowadays a de-facto standard format for genome description. Although there are several tools for GFF visualization, an open source application with advanced visualization features is missing. This work presents a design of such a tool. The application has a graphical user interface to simplify the user's work and combines the advantages of existing commercial products with free access. The application provides simple way to import user's biological data from a GFF file, creates hierarchical tree of individual elements including a detailed internal structure visualization in a subwindow.
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Prediction of Secondary Structure of Proteins Using Cellular Automata
Brigant, Vladimír ; Drahošová, Michaela (referee) ; Bendl, Jaroslav (advisor)
This work describes a method of the secondary structure prediction of proteins based on cellular automaton (CA) model - CASSP. Optimal model and CA transition rule parameters are acquired by evolutionary algorithm. Prediction model uses only statistical characteristics of amino acids, so its prediction is fast. Achieved results was compared with results of other tools for this purpose. Prediction cooperation with a existing tool PSIPRED was also tested. It didn't succeed to beat this existing tool, but partial improvement was achieved in prediction of only alpha-helix secondary structure motif, what can be helful if we need the best prediction of alpha-helices. It was developed also a web interface of designed system.
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Prediction of Protein Stability upon Mutations Using Machine Learning
Malinka, František ; Martínek, Tomáš (referee) ; Bendl, Jaroslav (advisor)
This thesis describes a new approach to the detection of protein stability change upon amino acid mutations. The main goal is to create a new meta-tool, which combines the outputs of eight well-established prediction tools and due to suitable method of consensus making, it is able to improve the overall prediction accuracy. The optimal strategy of combination of outputs of these tools is found by using a various number of machine learning methods. From all tested machine learning methods, KStar showed the highest prediction accuracy on the training dataset compiled from experimentally validated mutations originating from ProTherm database. Due to this reason, it is chosen as an optimal prediction technique. The general prediction abilities is validated on the testing dataset composed of multi-point amino acid mutations extracted also from ProTherm database. Since the multi-point mutations were not used for training any of integrated tools, we suppose that such comparison is objective. As a result, the developed meta-tool based on KStar technique improves the correlation coefficient about 0.130 on the training dataset and 0.239 on the testing dataset, respectively (the comparison is being made against the most succesful integrated tool). Based on the obtained results, it is possible to claim that machine learning methods are suitable technique for the problems from area of protein predictions.
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Computational Methods for Annotation Analysis of Genetic Variations
Fülöp, Tibor ; Bendl, Jaroslav (referee) ; Martínek, Tomáš (advisor)
Analýza a interpretace variací DNA je důležité pro zkoumání genetického pozadí dědičnosti, nemocí a jiných fenotypových rysů. Tato práce stručně úvadí oblasti molekulární biologie a základních principů genetiky, popisuje metody pro anotační analýzy genetických variací, genomové asociační studie a metody pro analýzy obohacení s jejich implementací. V rámci této práce jsme představili nový webový nástroj Varanto, který může být použit k anotaci, vizualizaci a analýze genetických variací. Může být použit k analýze obohacení anotací pomocí hypergeometrického testu pro danou množinu variací. Varanto obsahuje uživatelské webové rozhraní vyvinuté pomocí frameworku Shiny jazyka R. Výkon a funkcionalita nástroje jsou testovány a demonstrovány podle výkonových benchmarků a na základě analýzy a interpretace dat z dříve publikovaných genomových asociačních studií.
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Instruction-Controlled Cellular Automata
Bendl, Jaroslav ; Žaloudek, Luděk (referee) ; Bidlo, Michal (advisor)
The thesis focuses on a new concept of cellular automata control based on instructions. The instruction can be understood as a rule that checks the states of cells in pre-defined areas in the cellular neighbourhood. If a given condition is satisfied, the state of the central cell is changed according to the definition of the instruction. Because it's possible to perform more instructions in one computational step, their sequence can be understood as a form of a short program. This concept can be extended with simple operations applied to the instruction's prescription during interpretation of the instructions - an example of such operation can be row shift or column shift. An advantage of the instruction-based approach lies in the search space reduction. In comparison with the table-based approach, it isn't necessary to search all the possible configurations of the cellular neighbouhood, but only several areas determined by the instructions. While the groups of the inspected cells in the cellular neighbourhood are designed manually on the basis of the analysis of the solved task, their sequence in the chromosome is optimized by genetic algorithm. The capability of the proposed method of cellular automata control is studied on these benchmark tasks - majority, synchronization, self-organization and the design of combinational circuits.
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Predictor of the Effect of Amino Acid Substitutions on Protein Function
Musil, Miloš ; Martínek, Tomáš (referee) ; Bendl, Jaroslav (advisor)
This thesis discusses the issue of predicting of the effect of amino acid substitutions on protein funkcion, based on phylogenetic analysis method, inspired by tool MAPP. Significant number of genetic diseases is caused by nonsynonymous SNPs manifested as single point mutations on the protein level. The ability to identify deleterious substitutions could be useful for protein engineering to test whether the proposed mutations do not damage protein function same as for targeting disease causing harmful mutations. However the experimental validation is costly and the need of predictive computation methods has risen. This thesis describes desing and implementation of a new in silico predictor based on the principles of evolutionary analysis and dissimilarity between original and substituting amino acid physico-chemical properties. Developed algorithm was tested on four datasets with 74,192 mutations from 16,256 sequences in total. The predictor yields up to 72 % accuracy and in the comparison with the most existing tools, it is substantially less time consuming. In order to achieve the highest possible efficiency, the optimization process was focused on selection of the most suitable (a) third-party software for calculation of a multiple sequence alignment, (b) overall decision threshold and (c) a set of physico-chemical properties.
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Prediction of the Effect of Amino Acid Substitutions on the Secondary Structure of Proteins
Kadlec, Miroslav ; Vogel, Ivan (referee) ; Bendl, Jaroslav (advisor)
This thesis is focused on amino acid substitutions and their impact on protein secondary structure. The main aim is to prove, that although the protein sequence is frequently mutated during the evolution, protein secondary structure is more robust against changes. In this case, the elements of protein secondary structure stay almost unchanged although a significant number of substitutions is observed. The proof of this hypothesis was obtained by developed simulator of evolution which employs two well-estabilished predicting tools: PSIPRED for prediction of protein secondary structure and PhD-SNP for prediction of the effect of amino acid substitution on protein function. The results of the experiments are provided as graphs and their meainings is discussed.
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Visualization of DNA Secondary Structures in R/Bioconductor
Jaroš, Marta ; Bendl, Jaroslav (referee) ; Martínek, Tomáš (advisor)
This bachelors thesis deals with the visualization techniques of the secondary structures of DNA. It summarizes and discusses some of the current methods of visualization. It explains the problem and its importance from the standpoint of molecular biology. The main aim of the work is the design of a generic algorithm for visualization of secondary structures of DNA, specifically palindromes and triplexes, and its implementation into the environment R/Bioconductor. It focuses in particular on the area of 2D graphical imaging of these secondary structures of DNA. The result of the work is 2D visualization support for R/Bioconductors software packages which provide searching of the characteristic sequence of palindromes and triplexes in DNA sequences.
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