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Analysis of metabolites produced by yeast colonies and biofilms
Karásek, Filip ; Palková, Zdena (advisor) ; Dostál, Jiří (referee)
Some time ago it was shown (proved, described) that bacteria can communicate and regulate a gene expression by using small molecules. This phenomenon is called quorum sensing. The same phenomenon has been recently described in yeast. In yeast there are still many questions about the mechanism of sensing via small molecules. Few works and publications have described the impact of some small molecules, such as phenylethylalcohol or tryptophol, on morphology on Saccharomyces cerevisiae cell. The knowledge about the impact of the small molecules on the yeast multicellular community, like colonies, is still very limited these days. The aims of this work are analysis of exometabolites produced by colonies of different yeast strains cultivated on various solid complex media, by an untarged metabolomic approach. In accordance with the result of the exometabolites analyses we are going to test the impact of the selected substance on Saccharomyces cerevisiae colony morphology. The third part of this work is about the construction of Saccharomyces cerevisiae strains with deletion or lowering the expression of genes which encode proteins that are important in decarboxylation step of the Ehrlich pathway. Key word: Saccharomyces cerevisiae, microcolonies, tryptophol, isoamyl alcohol, isovaleric acid, colony...
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The secreted aspartic proteases of Candida parapsilosis.
Marečková, Lucie ; Dostál, Jiří (advisor) ; Novotný, Marian (referee)
Candida parapsilosis is an opportunistic fungal pathogen of humans causing a variety of infections. Immunocompromised individuals represent the most threatened group of patients. The increasing frequency of infections and occurrence of drug resistant strains are the main reasons for research focused on novel antimycotic compounds. Inhibition of secreted aspartic proteases (Sap) of pathogenic Candida spp. appears to be a potential target of therapeutic intervention. The genome of C. parapsilosis contains at least three genes coding for secreted aspartic proteases, denominated SAPP1-3. Protease Sapp1p has been well biochemically and structurally characterized, whereas Sapp2p and Sapp3p have been given less attention. The first part of the thesis is focused on structural analysis of Sapp1p complexes with selected peptidomimetic inhibitors binding to the active site of the enzyme. In addition, complex of the isoenzyme Sapp2p with the well-known secreted aspartate inhibitor Pepstatin A has been analyzed. The second part is related to the fact that C. parapsilosis belongs to the Candida spp. with the unique ability to translate standard leucine CUG codon mostly as serine. Even though it is a non-conservative substitution of hydrophobic amino acids for a hydrophilic one, this unique ability is maintained for more...
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Application of blood flow restriction by a sport training of climbers - an innovative training method for sportsmen?
Javorský, Tomáš ; Baláš, Jiří (advisor) ; Dostal, Jiří (referee)
Title: Application of blood flow restriction by a sport training of climbers - an innovative training method for sportsmen? Author: Tomáš Javorský BSc. Department: Department of Physiology Supervisor: doc. Jiří Baláš, Ph.D. Abstract: The most common injuries of performance climbers include tendon injuries of finger flexors. This kind of injury can leave a sportsman unable to follow his training programme for several months, which can have a crucial impact on his peak season. The thesis comprised a comparison of a high-intensity training performed at 70% of muscle strength maximum, with a blood flow restriction training performed at a 30% muscle load, and also the physiological and functional aspects of the training. Objectives: The presumption is, that the combination of a low muscle load with an ischemy will achieve the same results as a high-intensity training. We also presume, that the alterations in muscle oxygenation remain the same despite different amounts of performed muscle work. Methods: 13 participants finished the experiment performed in the form of a crossover study. During the experiment the muscle oxidative capacity and the extent of the muscle deoxygenation were measured by spectroscopy. The maximum force, critical force, impulse and the impulse above the critical force point were measured...
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Využití akustické emise při hodnocení procesu obrábění
Dostál, Jiří
The thesis deals with the application of acoustic emission system to the machining process. The thesis describes the gist of the machining, the influence of the cutting conditions on the machining process, and attention is also focused to the used tooling materials and creation of sliver. Another part deals with acoustic emission, its basic characteristics and areas of its use. In the experimental part, is determine the measurement objective, is described there methodology of the measurement and the data obtained from the measurement is then evaluated.
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Vliv stupňovaných dávek dusíku na výnos a kvalitu osiva kukuřice
Dostál, Jiří
This paper undertakes an assessment of the impact of staggered doses on the yield and quality of maize seed. The task was resolved in the form of a semi-operational field test on a seed multiplication field for maize in the municipality of Kelčany in 2016. 90 kg.ha-1 N was applied to all variants, followed at the 10-leaf stage by a staggered application of nitrogen contained in DASA fertilizer. The test comprised five variant dosages: 1st - fertilized with 120 kg.ha-1 N, 2nd - 90 kg.ha-1 N, 3rd - 60 kg.ha- 1 N, 4th - 30 kg.ha-1 N, and 5th variant - no fertilizer. After harvesting, grain yield at t.ha-1 was determined at 14 % dry mass. For determining the quality of seed, the maize was calibrated by grain size fractions and the germination rate was tested. For Variant 1, which received the highest fertilizer dosage, the highest grain yield was established compared to the control group. For the other variants, no substantial difference in yield was observed. Based on this one-year field test, the most suitable nitrogen doses in relation to yield and seed quality are 90 kg.ha -1 N and 60 kg.ha-1 N.
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Hodnocení kořenového systému a infiltrační schopnosti půdy u vybraných druhů trav
Dostál, Jiří
Lolium, Festuca species, and xFestulolium interspecies hybrids are widely used in agriculture, these species are considered the optimal grass species for intensive forage production. Lolium species are susceptible to abiotic stress, which has an increasing trend with the forthcoming climate change. Therefore, Festulolium interspecies hybrids have been bred, which have suitable parameters (drought resistance, ability of roots to penetrate through the compacted soil layers, better nutrient availability, etc.) to ensure a quality production and performance of other ecosystem services. Root biomass and root architecture are critical for meeting a number of ecosystem functions. In this work, I focused on the evaluation of the root system and the comparison of the soil infiltration capacity in selected Graminacae species. To compare selected parameters, grasses were grown in tubes filled with sand. Lolium multiflorum (cv. DALLARA), Festuca pratensis (cv. HYPERBOLA), Festulolium braunii (cv. HOSTYN), Festulolium krasanii (cv. HYKOR and HIPAST), Festulolium loliaceum (cv. PRIOR) and Trifolium pratense (cv. CALLISTO) species have been tested. The parameters evaluated were following: plant length, number of tillers, maximum rooting depth, total root length, root volume, root surface, root length in single thickness categories, dry matter of above-ground and underground biomass. The highest values were measured in Lolium multiflorum (cv. DALLARA) and in Festulolium braunii (cv. HOSTYN). Another part of the work was the sampling and evaluating roots from the soil on experimental plots in Vatín. In this measurement, Festuca rubra (cv. GONDOLIN) and Festulolium krasanii (cv. HYKOR) were selected. There were not found statistically significant differences in the total root length, root surface and root volume parameters. Festulolium (cv. HYKOR) had significantly stronger roots in the comparison to Festuca rubra. The last part of the research was the comparison of the soil infiltration capacity in these species: Festuca rubra (cv. GONDOLIN) and Festulolium (cv. HOSTYN, PRIOR and HYKOR). The highest infiltration capacity was measured on the Festulolium loliaceum (cv. PRIOR) plot.
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Surgical Aspects of Brain Ischaemia Flowmetry in a Clinical Practice and Experiment
Dostál, Jiří ; Přibáň, Vladimír (advisor) ; Vaverka, Miroslav (referee) ; Navrátil, Ondřej (referee)
Dissertation summary Surgical aspects of brain ischemia Flowmetry in a clinical practice and experiment MUDr. Jiří Dostál, Dpt. of Neurosurgery, Charles University, Faculty of Medicine Supervising Tutor: doc. MUDr. Vladimír Přibáň, Ph.D., Dpt. of Neurosurgery, Charles University, Faculty of Medicine The aim of this dissertation is to assess the options and benefits of a transit time flow measurement (TTF) in brain ischemia prevention in neurosurgery. Case reports from the Department of Neurosurgery, Charles University, Faculty of Medicine in Pilsen show the use and the limits of TTF. Presented case reports show the need of an individual approach in the case of a complex brain vessel surgery. A group of patients surgically treated for an unruptured middle cerebral artery aneurysm was analysed. Possible restriction of blood flow after the clip placement was quantitatively assessed by TTF in the first subgroup of patients. No quantitative flow measurement was performed in the second subgroup. There was no statistically significant difference between the two groups in terms of ischemia prevention. Some cases may entitle the surgeon to consider TTF use. TTF measurement is an invasive procedure and it demands a careful approach to the vessel and its preparation. The authors suggest to leave the use of the TTF to...
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Methodical practice of taking samples fertilizers, plants and soil for determination of risk elements in agro-ecosystems and other parameters of soil fertility: applied methodology with certification
Kunzová, Eva ; Menšík, Ladislav ; Hejcman, Michal ; Dostál, Jiří
The methodology is describing latest findings on methods of sampling of barnyard manure, organic and organomineral fertilizers, samplings of vegetable material and soil for determination of risk elements content. As a part of the methodology there is description of laboratory methods for determination of dry matter content, pH, content of essential nutrients and risk elements in samples (of farmyard manure, organic and organomineral fertilizers, vegetable material and soil). Methodology is describing methods of characterization of quality of soil organic matter (SOM) and most important limit valuables of risk elements in fertilisers, substrates and soils. The application of methodology will be in the corporation farming on arable soil, grassland, classical and also ecological agriculture. It will be used also by accredited laboratories, agricultural consultant and in advisory framework of Ministry of Agriculture of Czech Republic etc. Methodology can be used by civil servants, students and teachers in secondary schools and agricultural universities etc.
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Comparison of NIRS and other methods to determine anaerobic threshold
Šimon, Jan ; Slabý, Kryštof (advisor) ; Dostal, Jiří (referee)
The aim of this study was to compare NIRS (Near-infrared spectroscopy) and respiratory parameters measurement in determination of anaerobic treshold. Additionally changes in muscle oxygenation (SmO2) were described during incremental bicycle excercise. Fifteen subjects, 9 men and 6 women took part in this study. To verify the reliability of the measurement, the experiment was performed in the form of a test/retest with a few day's delay. The value of SmO2 was measured in m. gastrocnemius lateralis and m. vastus lateralis. In addition, respiratory parameters and pulse rate were recorded during the examination. The data obtained show that the breakpoint in the SmO2 dynamics determined by the NIRS method means that the excercise intensity above the anaerobic threshold is reached, because the breakpoint is located in the area of the Respiratory Compensation Point. In the SmO2 parameter, it is also possible to monitor the equilibrium state during the rest phase. The SmO2 parameter after the ramp log terminates exceeds the value in the rest phase, and returns to the quiescent value usually within 2 minutes. The test/re-test method has verified the reliability of the measurement.
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