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Analytical evaluation of novel drug candidates from the group of iron chelators using HPLC I.
Schöngut, Michal ; Kovaříková, Petra (advisor) ; Kučera, Radim (referee)
Nowadays, high performance liquid chromatography (HPLC) belongs among the most modern and most frequently used analytical separation techniques. Biocompatible iron chelators are mainly used for the treatment of iron overload. Nevertheless, in the light of new information about physiological and patophysiological role of iron in organism, their potential use was widened into other diseases. Iron chelators were proved to have antioxidative, cardioprotective and cytostatic effects. Salicylaldehyde isonicotinoyl hydrazone is a biocompatible iron chelator, which also shows these activities. However, its short half life in plasma makes its use difficult. Nowadays, novel derivates of SIH were prepared to improve its stability in plasma. 2'-hydroxypropiophenone isonicotinoyl hydrazone (HPP-INH) is one of newly prepared SIH derivates. The aim of this study was to develop optimal chromatographic conditions for HPLC analysis of HPP-INH and to develop sample pretreatment method using precipitation for its analysis in plasma. The analysis was carried out on a Merck 250x4 mm column I.D. LiChrospher® 100, RP-18e (5 μm) protected with Purospher® 100, RP-18e (5 μm) guard column. The following mobile phase gradient condition was developed for HPP-INH purity evaluation: phosphate buffer (0,01 mol/l NaH2PO4 · 2 H20 water...
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Biotransfer of selected risk metals into plants and their accumulation and distribution in plant organs
Le Minh, Phuong ; Lachman, Jaromír (advisor)
Contamination of soils with heavy metals is one of the serious environmental problems threatening human being. Heavy metals are considered as the special hazard of soil pollutants because of the adverse effects on the plant growth, the amount, activity of useful microorganisms in soils and the quality of food. Regard to the persistent and toxicity, the heavy metals are toxic when we consider different kinds of pollutants in soils. In the soil, zinc (Zn), cadmium (Cd), lead (Pb) and mercury (Hg) toxicities frequently occur than the other metals because of their precipitation and sorption by the soil. It is a very dangerous situation because when these metals are taken up by plants, they can be transported to the food web and food chains.
In the present study, the accumulation of four heavy metals (mercury, zinc, lead and cadmium) in the whole grain of spring accessions of emmer, einkorn and common spring wheat cultivars and potato (Solanum tuberosum) is reported. Heavy and essential elements were monitored in potato cultivars in the exact field experiments and in hydroponically grown plants. The elements were determined by methods FAAS, ET AAS, and AMA (Advance Mercury Analysis). Statistical analyses were performed using SPSS 9.0 with the Tukey HSD (Honestly Significant Difference) test (alpha equal to 0.05).
In our study, the concentration of heavy metals decreased in the order zinc (Zn) > lead (Pb) > cadmium (Cd) > mercury (Hg) in the wheat grain. The comparison between three varieties of investigated wheat revealed that the emmer wheat was rich in zinc content (62.12 mg kg-1 dry matter), while the spring wheat had the lowest average concentration of zinc in the grain (40.99 mg kg-1 dry matter). Generally, the values of lead concentration in grain wheat varieties were low (ranging from 0.1268 mg kg-1 dry matter to 0.2950 mg kg-1 dry matter).
The concentrations of mercury in four typical growth stages of wheat (boot stage 10, heading stage 10.2 1/4 of head emerged, leaf-stage 10.2 and stage ripening 11 according to Feekes) were also determined. It has been shown that the concentrations of mercury in different wheat varieties were absorbed differently at different growth stages of plant. Stage 10.2 and leaf stage 10.2 showed the high mercury content (0.0152 mg kg-1 dry matter and 0.0214 mg kg-1 dry matter, respectively). Among individual varieties significant differences were determined.
Amounts of toxic and potentially toxic elements detected in investigated potato tubers are characterized by a large variability within investigated groups. Performing statistical analysis (one way ANOVA) showed that there were no significant differences between two investigated groups of samples (samples from Uhříněves and Valečov in the year 2013 and 2014) considering either one of investigated metals. Measurable levels of mercury were found in smallest amounts in all investigated potato samples comparing to other metals (Cd, Pb).
Plant cells compared to animal cells are characterized by the formation of cell walls. Plasma membrane or cell membrane is a biological active membrane separating the interior of cell from the outside environment. An adjusted method for isolation of protoplasts was developed and adapted for isolation of protoplasts from plant material (potatoes). In our experiment, the plants were grown hydroponically in the Research Institute of Plant Crops Prague-Ruzyně. If we examine the plant membrane, one option is to remove the cell wall by means of special mixture enzymes. Protoplasts were released in the dark at 25 degrees of Celsius for 18 hours. The 70 and 90 microns sieve was used to filter and then centrifugation for 5 minutes at 100 x g. All the steps were carefully carried out to prevent the damage or breakage of protoplasts.
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Competitive analysis of the hotel Dorint Don Giovanni
Duchoň, Tomáš ; Luštický, Martin (advisor) ; Dvořák, Jiří (referee)
The Master's Thesis is focused to the issue of competitiveness in Prague four star hotel. The goal of this work is to make strategic competitior analysis, map the current trends affecting tourism and on the basis of the evaluation results to formulate proposals and recommendations to the hotel's management. This work uses the selected analytical methods to determine the future direction of the hotel and eliminating its shortcomings.
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Analysis of water requirements of the field crops in areas with frequent occurrence of drought.
Zábranský, Petr ; Soukup, Josef (advisor) ; Jan, Jan (referee)
Summary
Water resources are an important part of ecosystems. In the water balance of the landscape, the variability of climate, soil factors, as well as high diversity of vegetation play an important role. Evapotranspiration represents a major passive component in the water balance of the basin. Unlike forests, where the water balance is particularly predictable due to the long-term development of the stands, regular crop rotation in agricultural systems and agricultural practices may cause rapid changes in water balance during much shorter time. It may sometimes result in irreversible changes in ecosystems with impact on landscape biodiversity. An understanding of the limiting environmental factors and exact determination of the water demands of plants makepossible not only an improvement of yield parameters, but it is also condition for understanding of the agroecosystems sustainability in the cultural landscape.
Field measurements of actual evapotranspiration were carried out in the period 2007 to 2015 in Velvary (Budihostice) in the Central Bohemia region, 210 m above sea level in the rain shadow area around Slaný territory. In terms of the average annual water balance (CHMI, 2014), the locality is regarded as the area with the difference between the average annual precipitation and annual potential evapotranspiration totals in amount of -200 mm, so the potential evapotranspiration slightly exceeds precipitation. Field measurements were conducted on commonly managed areas with a minimum size of the experimental plots of 1 ha.
The measurements confirmed differences between the crop water demands during the growing season. Different values of the actual evapotranspiration as well as the Bowen ratio values were estimated for the observed crops depending on the growth stage of crops. The lowest values of actual evapotranspiration were detected for Zea mays and Sorghum bicolor. Higher water demands were shown by Triticum aestivum and Hordeum vulgare. On the contrary, the highest values of actual evapotranspiration were found in stands of Beta vulgaris and Medicago sativa. According to the values obtained for crop coefficients (Kc), the crops of Z. mays, S. bicolor and T. aestivum had about a quarter lower values of Kc compared with M. sativa and B. vulgaris crops in the main growing season. In this work, the daily values of Kc, which are the basic characteristics of moisture requirements for individual crop were determined and can be used modelling of hydrological processes in agro-phytocoenoses. The evaluation of moisture requirement of crops by the water flow in plants (determined by the sap flow method) showed the expected differences between S. bicolor and Z. mays plants. Water use efficiency (WUE) was significantly higher in plants of C4 type (Z. mays and S. bicolor) compared with the rest of observed plants of C3 type (T. aestivum and H. vulgare).
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Novel Approaches to the Application of Electrochemical Volatile Compounds Generation in Spectrometric Methods
Červený, Václav
Various possibilities for the use of electrochemical generation of volatile compounds for the determination of trace and ultratrace quantities of elements using atomic absorption spectrometry and optical emission spectrometry, respectively, were studied in this work. The Thesis is divided into four thematic sections. Electrochemical cold mercury vapor generation is common to the first two parts. The third part is devoted to electrochemical generation of the volatile form of cadmium and the last part deals with the use of the electrochemical hydride generator as a derivatization unit for speciation analysis of arsenic compounds. The optimization of each individual determination was carried out including, for example, various designs of the generator of volatile compounds (forms) of the analyte, the changes in the design of the gas-liquid separator, optimization of the concentration and the flow rate of all the solutions and the carrier gas. However, the value of the electric current employed was the most important parameter. In the first section, the in-situ trapping system of the cold mercury vapor generated in the graphite furnace (with the inner surface covered with a gold foil) of the atomic absorption spectrometer was also designed and optimized. The absolute limit of detection, 80 pg, was...
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Managerial skills
Brůžková, Anna ; Kříž, Josef (advisor) ; Milan, Milan (referee)
The main focus of the thesis entitled Managerial skills are various areas of managerial skills which are essential for management of certain working positions and therefore necessary for efficient functioning of the whole organization. It addresses issues of the current level of managerial skills and their possible reinforcement in future. The thesis is divided into two parts.
The first part consists of theoretical sources dealing with topics such as manager´s personality profile, his or her personality features, knowledge and competences, and last but not least managerial roles and functions. The attention is mainly paid to soft managerial skills.
The second, analytical part, characterizes a chosen company and then performs analysis of the current level of employees´ managerial skills at one working position. This analysis is based on data acquired from a questionnaire research and a pen and paper interview with an employee of the organization. On the basis of foregone steps some proposals are set for strengthening the researched managerial skills in the organization. Implementation of these enhancements assumes simultaneous increase in the standards of several employees´ soft skills, which can positively influence the quality and increase of their performance and as a result improve the functioning of the whole organization.
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Determination of different forms of casein in milk
Kaňková, Veronika ; Hejtmánková, Alena (advisor) ; Markéta, Markéta (referee)
Casein proteins are important escpecially for cheese making. In addition to technology and other factors, casein concentration in milk and relative representation of individual casein fractions influence cheese yield. Majority fractions are alfa-casein, beta-casein and kappa-casein. For the determination of proteins in the milk can be used electrophoretic techniques or near infra-red spektrometry. High performance liquid chromatography (HPLC) is going to be used. HPLC is widely used analytical method, which is based on differential affinity of the substances to the mobile and the stationary phase.
The thesis has introduced the method of determining the casein fractions by HPLC. The method was partially optimized using cow milk and calibrated to the standard solutions, which were purchased casein fractions derived from the bovine milk. Real samples of cow, sheep and goat milk were analyzed. The goat milk was available in several variants: Sanski goat milk and white shorthair goat from domestic or farm breeding. All milk samples were analyzed for casein and casein fractions proportions. Chromatograms show that the casein formula is different in cow, sheep and goat milk. Different concentrations of the casein fraction in the milk of various animal species have been statistically detected in almost all cases. The exception was the concentration of beta-casein in the milk of white shorthair goat from the domestic and the farm breeding and cow milk. In these types of milk there was no statistically significant difference in the concentration of beta-casein. Analysis of individual samples of white shorthair goat milk from the farm breeding shown that casein content in the milk of different animals reared under the same conditions may be different. Ratios of beta-casein to alfa-casein, beta-casein to kappa-casein and alfa-casein to kappa-casein were evaluated in all samples. Interspecific comparisons proved that ratios were statistically significantly different in all milks. In the milk of Sanski goat, there was found the stable ratio of beta-casein to alfa-casein during lactation. For all goat milk there were typical higher values of the ratio of beta-casein to kappa-casein. The ratio of alfa-casein to kappa-casein was highest in the sheep milk. Despite some shortcomings, it is possible to use the HPLC method possible for these purposes, but it is necessary to continue with its optimization.
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Determination of vitamin E in wheat different grain discoloration types
Veverková, Markéta ; Hejtmánková, Alena (advisor) ; Faměra, Oldřich (referee)
The diploma thesis deals with the determination of vitamin E in grains of wheat kernels with unusual coloring. In the theoretical part is mentioned botanical characterization of wheat, barley and tritordeum, vitamin E and its chemical and biological aspects and basics of chromatography with a focus on the high performance liquid chromatography (HPLC).
The analysis to quanify vitamin E was performed in the experimental part of the thesis. The analysis was conducted with samples of winter and spring wheat, spring barley and spring tritordeum from harvests of 2014 and 2015. These were varieties with unusual coloring of the grain. The evaluation was conducted by variety (winter wheat, spring wheat, spring barely, spring tritordeum) and by the color of the kernels (blue aleuron, purple pericarp, yellow pericarp). Subsection part of the thesis is dedicated to a quantification of vitamin E during long-term storage.
Based on the determination of total vitamin E amount in all analyzed varieties of cereal grains with a different color is not statistically significant difference in the values of the total amount of vitamin E. The difference between the content of vitamin E in the samples of the same varieties of different cereals harvest from a year 2014 and a year 2015 were not statistically significant. All varieties of wheat were quantified four vitamers: alpha-tocopherol, beta-tocopherol, alpha-tocotrienol and beta-tocotrienol. The amount of other vitamers was below the limit of detection. The total content of vitamin E and contents of individual vitamers coincide with the data given in the literature for wheat varieties with standard color of grain. Spring barley contained a slightly higher average levels of total vitamin E amount in comparison with varieties of spring and winter wheat. The total average amount of vitamin E in varieties of spring tritordeum was also slightly higher than in varieties of winter and spring wheat. From the long term storage point of view, it is clear that the total amount of vitamin E in both varieties is relatively stable and shows no clear trend in function of storage time.
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Optimization of advantages on business current account
Hach, David ; Švecová, Lenka (advisor) ; Theodor, Michal (referee)
The basic aim of this thesis was to evaluate the profitability of current accounts offered by the five largest Czech banks. In this context it was proposing to create such an evaluation device, which is sufficiently versatile and reusable. After a thorough examination of the general principles of decision-making theory and the basic characteristics and instruments of current accounts has been developed appropriate analytical base for follow-up of the work. In the analytical part proved very useful hierarchy of objectives and criteria, as well as the use of exact methods for determining weights of criteria and selecting the appropriate option. For determining the weights of the criteria were used point scale method, preferential ranking method, the method of paired comparisons, Saaty's method and compensation method. For the selection of variants were used multicriteria utility functions, Saaty's method and compensation method.
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Strategic Management in NGA, Ltd.
Ustinova, Vlada ; Svobodová, Ivana (advisor) ; Müllerová, Jana (referee)
This thesis deals with the process of strategic management. The paper includes the description of its components, strategic analysis, suggestion of strategic alternatives and defining the strategy of the specific company. The work consists of two parts: theoretical and analytical. The first part covers the theoretical foundations related to the strategic management process and information about the specifics of strategic management in a small business, as well as the specifics of small business in Russia. The analytical part includes the description of the industry of the chosen company, an introduction to its history, determination of the mission, vision, objectives, the strategic analysis of the company, proposal of possible strategic alternatives and determination of the resulting strategy. The goal of the paper is to define explicitly the current strategy of the chosen company as well as to suggest other strategic alternatives of company's survival and development.
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