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Proteins demaged by oxidative stress, their role in physiology and ageing of yest cells
Mikešová, Jana ; Palková, Zdena (advisor) ; Borčin, Kateřina (referee)
Reactive oxygen species (ROS) are regularly produced in cells as a by-product of aerobic metabolism. Hence, organisms developed various defence mechanisms, which are able to avoid molecular damages caused by ROS under physiological conditions. In stress conditions, however, such defence mechanisms are not sufficient to avoid molecular damages. Accumulation of oxidized proteins is supposed to be a reason for ageing and many diseases including Friedreich's ataxia, Amylotrophic lateral sclerosis, Alzheimer's disease and many others. During oxidative stress, reactive oxygen species are reflected in oxidation of cystein residues in transcription factors, regulation proteins and active canters centers of enzymes. Oxidative modifications however could lead also to changes in transcription factor activity and activation of specific pathways, including changes in gene expression, cell cycle and proteolysis. This work shows defence mechanisms, ROS and proteins altered by reactive oxygen species that may function as important signalling molecules, which are essential for many cellular processes.
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Klinicky významné druhy kvasinek a jejich interakce s hostitelem
Novosadová, Zuzana ; Palková, Zdena (advisor) ; Beranová, Jana (referee)
Pathogenic yeasts are nowadays a serious threat for mammalian host. They can cause dangerous diseases, which in many cases even result in death. Pathogens increase the chances of systemic infections by many virulence mechanisms. Experiments addressing the pathogenhost interactions are crucial for defeating these types of infections within the human body. Host-pathogen interactions are very complex and include all components of multicellular host organism. Recently, scientists have focused on the interaction of the mammalian immune system and pathogenic yeasts in more detail. This work summarises interactions of pathogen with selected host cells, especially with macrophages. Yeast pathogens, especially Candida albicans, are capable of influencing the gene expression in interacting cells. These pathogens are capable of modulating the expression while engulfed inside macrophages and other cells of the immune system. Pathogenic yeasts can also change the overall characteristics of their surrounding environment. C. albicans can sense pH and influence it. Therefore, it can increase its virulence by the changes of pH leading to autoinduction of morphological transitions. This work briefly reviews how selected yeast pathogens influence their surroundings while interacting within the host organism. Deeper...
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Role of MDR transporters in yeast biofilm resistance
Urbanová, Daniela ; Palková, Zdena (advisor) ; Seydlová, Gabriela (referee)
This work is focused on multidrug resistance transporters (MDR) and their role in the drug resistance of yeast biofilms. Biofilms are structured microbial communities that are markedly different from planktonic cells. Biofilm cells produce extracellular matrix and display other typical characteristics related to their enormous resistance to antimicrobial agents. MDR pumps contribute to higher resistance of biofilms only during early phases of biofilm development; later, MDR pumps are substituted by many other mechanisms. Cdr1p, Cdr2p and Mdr1p are the most important MDR transporters of Candida albicans. Cdr1p and Cdr2p cause resistance to azoles - fluconazole, ketoconazole and itraconazole, which have been widely used as drugs against yeast infections. Mdr1p contributes also to the resistance to fluconazole. Drug resistance causes considerable problems in the treatment of fungal infections. For this reason, it is so important to understand drug-resistance mechanisms of yeast communities. Keywords: resistance, MDR transporters, Candida albicans, biofilms
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Phonotactic framework of the Czech word and stress-group
Churaňová, Eliška ; Volín, Jan (advisor) ; Palková, Zdena (referee)
This master thesis provides a relatively detailed description of the consonant-vowel structure of standard spoken Czech. The first part covers approaches to and findings on the combinatorial system and distribution of sound units in speech; aspects of continuous speech segmentation into intonation phrases and stress groups, phonotactics of languages in general and Czech in particular, and speech rhythm are also addressed. Recordings of 12 professional speakers of Czech - comprising 6639 words and 5368 stress groups in total - have been used to create data sets that have enabled the author to describe CVCV structures of Czech words and stress groups. The results of this research present frequencies of words and stress groups and their relations to word-class dimension, frequencies of phones in words and stress groups; in this respect, both syllabic liquids and glottal stops have been taken into account. Further, the thesis includes an overview of the most frequent CVCV patterns in words and stress groups and their variability with regard to word classes. The final part focuses on how frequently consonants, vowels and their pairs and trios occur at different places within a unit. The results are continuously compared both between themselves and with the research that used the larger SYN2005 written...
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Sound variability of Czech interrogative sentences in spontaneous speech
Hýblová, Lucie ; Volín, Jan (referee) ; Palková, Zdena (advisor)
This work undertakes the problems of intonation in Czech. The aim of this research is to analyse and describe phonetic variability of Czech interrogative sentences, particularly in spontaneous speech. The intonation fulfils certain linguistic functions in Czech. Structures of the basic patterns of intonation (melodeme) are described and standardized, but aspects of spontaneous and dialogic utterances have not been described sufficiently yet. Our research deal with variability, occurrence and behaviour of basic types of questions (yes-no and wh-questions) and their modifications in spontaneous speech, which are given by context and situation or given by the difference between semantic and formal aspects. It was found yes-no questions (with all their modifications) to be the most frequented questions in spontaneous dialogues of our type. We also found semantic modifications to have the same distribution as the standard ones whereas formal congruent types behave unlikely. The research is based on spontaneous task-oriented dialogues and read text of dialogical character. We focuse on detail description of concrete tonal progression of melodic contour, we also take into account broader melodic context in the case of basic types of questions. We analyse both types oftext in the same manner, then the comparison is...
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Pronunciation of two distinct "i" Vowels in the East Lach dialect
Blažková, Jana ; Veroňková, Jitka (referee) ; Palková, Zdena (advisor)
The vowel inventory of standard Czech includes five short vowels /a/, /e/, /i/, /o/, /u/ and five long vowels /a:/, /e:/, /i:/, /o:/, /u:/. Nevertheless, the dialectological literature indicates two distinct /i/ vowels, /i/ and /y/, in all the groups of the Lach dialects. The contrast of these two phonemes has a historical origin and has already disappeared in most of Czech and Moravian dialects. The objective of the diploma thesis "Pronunciation of Two Distinct /i/ vowels in the East Lach Dialect" is to witness the present state of the production and perception of two /i/ vowels in the East Lach dialect. Former dialectological texts still indicate the opposition as conserved, though considering the general recession of Czech dialects, the diploma thesis aims to verify if the East Lach dialect still distinguishes the /i/ and /y/ vowel and if this should prove to be the case, to determine the acoustic features that assure its perception. The research was based on minimal pairs and syllables, where the /i/ vowels were preceded by different consonants. The minimal pairs and syllables were inserted in text which was read by the speakers and recorded. Within the framework of the diploma thesis, 30 senior speakers of the East Lach dialect were recorded. Afterwards, six speakers were chosen to feature in two...
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Intonation of a monosyllabic word as part of a polysyllabic stress-group
Spilková, Helena ; Volín, Jan (referee) ; Palková, Zdena (advisor)
The diploma work focuses on investigating the melodic properties of compound stress-groups (i.e. polysyllabic stress-groups that include a monosyllabic word). The primary method is the analysis of melodic course in ambiguous syllable sequences. In each of these syllable sequences, one meaning alternative included a monosyllable in various positions and the other alternative was constituted by polysyllabic words only. The melodic course data are simultaneously correlated with the perception test results that provide a feedback on perception of individual instances. By comparing various instances of compound stress-groups the work pursues the detection of melodic patterns that occur in compound stress-groups unlike in simple stress-groups (formed by one word only). The work also contains a melodic transcription system design intended to retain melodic properties on the stress-group level.
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The influence of syntactic structure (conjunctions) on spoken language (utterance section, intonation, pauses). Auditory analyses
Jelínková, Ivana ; Palková, Zdena (referee) ; Saicová Římalová, Lucie (advisor)
The presented thesis "The Influence of Syntactic Structure (Conjunctions) on Spoken Language (Tone Unit, Intonation, Pauses) - Auditory Analyses" explores the relations between conjunctions A (AND), ŽE (THAT), ABY (IN ORDER THAT), PROTOŽE (BECAUSE), ALE (BUT) in an exactly given syntactic structure and a system descritption of phonetic form of language - the tone unite, the intonation, and the pause. This research is based on the comparison of the public read and the public notread, but prepared utterances. At first we segment the chosen examples into the stress units; then we try to confirm the hypothesis that a conjuction begins a new tone unit; within the intonation, we monitor what is typical for the melodic line in the stress unit before the conjunction; the last part of our research is dedicated to pause and to their positions near the stress unit containing the conjunction. The research is based on the auditory analyses, therefore it does not use the instrumental analyses.
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