National Repository of Grey Literature 94 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Determination of selenium and manganese in cerebrospinal fluid by atomic absorption spectrometry
Jiráková, Lucie ; Kotaška, Karel (advisor) ; Klapková, Eva (referee)
The aim of this study was to confirm the use of electrothermal atomic absorption spectrometry for the determination of selenium and manganese in the cerebrospinal fluid and to investigate concentrations of selenium and manganese in selected group of patients. For selenium was determined the detection limit 2,9 μg/l, for manganese 0,26 μg/l. 73 patients were examined (31 women, 42 men) whose average age was 14,1 years. The patients were divided into two groups according to age (56 children, 17 adults) and into two subgroups according to diagnoses (oncological, neurological). The control group consists of 18 subjects (5 women, 13 men, average age 21,7 years) with non-oncological and non-neurological diagnoses. We found significantly increased selenium concentrations in cerebrospinal fluid in the control group, compared with the group with neurological diagnoses (median = 14,4 μg/l vs. 12,4 μg/l, p < 0.05). Elevated levels of manganese in cerebrospinal fluid was observed in a group of children with oncological diseases compared with control group (1,2 μg/l vs. 0,5 μg/l, p < 0.05). Determination of selenium and manganese in the cerebrospinal fluid may have diagnostic importance in selected groups of patients. Powered by TCPDF (
Comparison of selenium extraction efficiency from food supplements
Molnárová, Lucia ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
The aim of this bachelor thesis was comparison of selenium extraction efficiency from food supplements which contain various declared forms of selenium. The method of atomic absorption spectrometry with flame atomization was used to determine the efficiency of the extraction. The first step for the determination of selenium in four real samples was the experimental finding of optimal conditions for selenium determination by flame AAS technique. Optimized parameters included the flame composition, the fuel flow rate, the angle of burner rotation, the horizontal burner position and the spectral range. During the testing the flame composition, higher responses were measured by using air as an oxidant, and therefore acetylene-air flame was used to other optimize and measure real samples. After optimization of the conditions, the calibration dependence was determined and the basic characteristics of the measurements were calculated. The detection limit and determination repeatability, sensitivity and operating range were determined for selenium determination. The detection limit was 0.12 mg dm-3 . The real samples of the food supplement tablets were mechanically homogenized and transferred to aqueous solutions, which were subsequently analyzed by the optimal conditions. The highest extraction efficiency...
The selenium effect on secondary metabolites production in in vitro cultures of medicinal plants - II
Ošťádalová, Tereza ; Tůmová, Lenka (advisor) ; Kašparová, Marie (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Tereza Ošťádalová Supervisor: Doc. PharmDr. Lenka Tůmová, CSc. Title of diploma thesis: The selenium effect on secondary metabolites production in in vitro cultures of medicinal plants - II. Key words: callus, suspension culture, abiotic elicitor, selenium, Fagopyrum In vitro plant cultures usually produce only a small amount of secondary metabolites. The method of elicitation is one of the options how to increase the production of these substances. The effect of selenium as abiotic elicitor on rutin production in callus and suspension culture of Fagopyrum esculentum Moench., variety Pyra was observed in this study. The release of rutin into the nutrient medium was studied as well. The cultivation was performed in Murashige and Skoog (MS) nutrient medium which was enriched with 1 mg/l of 2,4-dichlorophenoxyacetic acid. The solution of selenium in three different concentrations (c1 = 9.012.10-3 mol/l, c2 = 9.012.10-4 mol/l, c3 = 9.012.10-5 mol/l) was used. The samples were taken after 6, 12, 24, 48, 72 and 168 hours of elicitor treatment. The rutin content was determined by high-performance liquid chromatography (HPLC). The elicitation led to increasing of rutin amount in callus and also in suspension...
UV-photochemical generation of volatile compounds of selenium and tellurium
Nováková, Eliška
The presented thesis deals with UV-photochemical generation of volatile compounds of Se and Te from various species. The aim of the project was to expand the current state of knowledge by the application of photocatalytic reduction of higher oxidation states of Se and Te for the speciation analysis based on UV-photochemical generation of volatile compounds. The first step of the study was the assembly of the apparatus for the photocatalysed UV-photochemical generation of volatile compounds. The material of reactor and the whole experimental set-up were based on literature survey and previous research done in our research group. Experiments were directed towards finding the optimum conditions for generation of volatile compounds of selected model elements Se and Te. Se was studied as the element most commonly determined by the UV-photochemical generation of volatile compounds. Conversely, Te was selected as a model analyte representing elements forming less stable volatile compounds. The second part was the application of the optimised method of photocatalysed UV- photochemical generation of volatile Se compound to the determination of Se in water matrices, liquid certified reference materials and also samples of dietary supplements. TiO2/UV-photochemical generation was also successfully modified to...
Optimization of antibacterial properties of polymer-phosphate bone fillers
Grézlová, Veronika ; Michlovská, Lenka (referee) ; Vojtová, Lucy (advisor)
Tato diplomová práce je zaměřená na přípravu polymer-fosfátových kostních cementů. Cílem je optimalizovat antibakteriální vlastnosti daného cementu přídavkem selenových nanočástic (SeNPs). V teoretické části práce je popsána charakteristika kosti, vlastnosti fosforečnanu vápenatého (TCP) a jeho polymorfů, použití kostního cementu a antibakteriálních nanočástic v medicíně. Experimentální část se věnuje přípravě vzorků, popisu metod a vyhodnocení vlivu SeNPs na vytvrzování kostního cementu, morfologii, krystalinitu, mechanické, reologické a antibakteriální vlastnosti. Výsledkem je zvýšení injektovatelnosti cementu a zrychlení jeho vytvrzování včetně pozitivního vlivu na mechanické vlastnosti. Antibakteriální vlastnosti vzorků byly testovány použitím diskové i diluční metody, což vedlo k pozitivnímu inhibičnímu účinku SeNP na grampozitivních bakteriích (G+), zejména Staphylococcus aureus a methicillin rezistentní Staphylococcus aureus. Kvantitativní uvolňování SeNP z modifikovaného kostního polymer-fosfátového cementu umožňuje jeho použití jako antibakteriální kostní výplně (například pro léčbu zánětu kostí).
Ovlivnění jakostních parametrů vajec netradičními krmivy
Vincentová, Klára
This bachelor thesis contains issues affecting quality parameters of eggs with unconventional feed. Chia seeds (Saliva hispanica), safflower (Carthamus tinctorius) hemp seeds (Cannabis sativa) and cultivated algae (Chlorella vulgaris), (Isochrysis galbana), (Nannochlorapsis oculata), (Phaeodactylum tricornutum) feed, which influences eggs profil of polyunsaturated fatty acids. Marigold (Tagetes erecta), turmeric (Curcuma longa), tomato (Solanum lycopersicum) and cultivated algae (Chlorella vulgaris), (Nannochlorapsis oculata), (Phaeodactylum tricornutum) feed, which complements carotenoids and natural dyes to eggs. Cassava (Manihot esculenta), garlic (Allium sativum), tea plant (Camellia sinensis) and lucerne (Medicago sativa) feed, which reduces the content of cholesterol in eggs. Selenized algea (Chlorella vulgaris) and basil (Ocimum gratissimum) feed, which increases the content of mikroelements in eggs. Thyme (Thymus vulgaris), oregano (Origanum vulgare), chamomile (Matricaria chamomilla) and mint (Mentha piperita) feed, which increases the content of antioxidants in eggs.
Selen ve výživě dojnic v ekologickém chovu
Šnajdr, Vladimír
Šnajdr Vladimir: Selenium in the diet of dairy cows in organic farming, Final thesis, Mendelu Brno, 50 pages. Selenium is one of a number of trace elements that are indispensable for the life of all species. Exceeding limits of the daily dose of selenium in the diet can cause toxicity of tthe organism. However, selenium deficiency can lead to diseases, particularly for species with high susceptibility to various kinds of diseases. The aim of the thesis was to investigate the influence of dietary selenium on qualitative and quantitative parameters of dairy cows in organic farming. The experiment itself was made on an organic dairy farm. The experiment involved 20 pieces of Holstein breed cows. They were divided into two balanced groups being at same stage of lactation. All the cows were fed a basic ration in the form of TMR with the addition of mineral premix Detamin GA Spezial designed for organic farms. The experimental and control group of cows took of 20.5 kg dry matter of feed/head/day. The basal diet contained 0.17 mg selenium /kg. Animals had ad libitum access to water. Selenium was added to the diet at the dose of 0.3 mg/kg (as selenomethionine) in the first group of cows (n=10). The second group of cows (n=10) served as a control without addition of selenium (control group of animals received only selenium from native sources). At the end of the experiment was after administration of selenium in the diet after 15 days in the group of cows examined detectable amount of selenium, which was constant throughout the duration of the experiment. The experimental group with selenium level ranged from 15 to 45 days in the interval from 0.13 to 0.15 mg/ml. In the control group, the amount of selenium throughout the entire duration of the experiment under the detection limit. The quantity of somatic cells was significantly reduced in the test group cows 128 thous./ml (P <0.05). Reducing the number of somatic cells was also observed even in the control group (about 49 tis./ml). The urea concentration significantly decreased in the experimental and control groups of 14.3 mg/100 ml (P <0.05) respectively about 13.7 mg/100 ml (P<0.05). The addition of selenium can improve animal health and to ensure the production of so-called functional foods Formula clause:Prohlašuji, že jsem práci: Selen ve výživě dojnic v ekologickém chovu vypracoval samostatně a veškeré použité prameny a informace uvádím v seznamu použité literatury. Souhlasím, aby moje práce byla zveřejněna v souladu s § 47b zákona č. 111/1998 Sb., o vysokých školách ve znění pozdějších předpisů a v souladu s platnou Směrnicí o zveřejňování vysokoškolských závěrečných prací. Jsem si vědom, že se na moji práci vztahuje zákon č. 121/2000 Sb., autorský zákon, a že Mendelova univerzita v Brně má právo na uzavření licenční smlouvy a užití této práce jako školního díla podle § 60 odst. 1 autorského zákona. Dále se zavazuji, že před sepsáním licenční smlouvy o využití díla jinou osobou (subjektem) si vyžádám písemné stanovisko univerzity, že předmětná licenční smlouva není v rozporu s oprávněnými zájmy univerzity, a zavazuji se uhradit případný příspěvek na úhradu nákladů spojených se vznikem díla, a to až do jejich skutečné výše.
Vliv selenu, zinku, vitamínu C a E na potlačení tepelného stresu u kanců
Půlpánová, Barbora
The aim of the study was influence of the complex of two elements (zinc, selenium) and two vitamins (vit C, vit E) on the organism of pigs under heat stress. Twenty boars of the Duroc breed were included in the experiment. The boars were approximately the same age and weight, housed individually. They were divided into 2 groups. The control group (n = 6) was fed only to a basic feed mixture containing 0.02 mg Se; 21.5 mg Zn; 9.9 mg of vitamin E and 16.0 mg of vitamin C. In addition, 0.5 mg of selenomethionine, 70 mg of alpha-tocopherol, 70 mg of zinc oxide and 350 mg of ascorbic acid were added to the diet (n = 6). The experiment took place from June to September at the insemination station in Velké Meziříčí. The control group showed a slight increase in ejaculate volume (by 19 %), which is common in the summer months. At the same time, the sperm concentration was unstable, it increased by 15 % in August, but fell below the baseline by 3.5 % in September. Motility was around 69 % during the experiment. Statistically significant was an increase (by 15 %) of morphologically abnormal sperm in the ejaculate (P < 0.05). The experimental group had higher ejaculate from the beginning. However, the volume curve was almost identical to the experimental group. The sperm concentration increased by 23 % in the trial group after adding antioxidants. During the experiment the concentration only slightly decreased. Motility in the experimental group averaged 70 % and did not change significantly during the experiment. Even in the control group there was a statistically significant increase in morphologically abnormal sperm (by 12.3 %), (P <0.05). From the results it can be concluded that the increased amount of selected antioxidants did not have a demonstrable effect on the improvement of the ejaculate quality, but it can be assumed that this quantity has ensured the stability of the seed parameters.
Vliv selenu na růst heterotrofní formy řasy Chlorella
Novák, Martin
This diploma thesis (Heterotrophic incorporation of selenium in Chlorella sp.) focuses on characterisation of the genus Chlorella and large-scale use of algae for biofuel and starch production. Besides that, the thesis contains an up-to-date summary of forms of autotrophic algae cultivation ranging from large-volume tanks covering the area of dozens of hectares down to laboratory cultivation in photobioreactors and heterotrophic cultivation of algae in fermenters. Experimental part of the thesis focuses on cultivation and observation of the heterotrophic growth of algae Chlorella vulgaris in relation to the concentration of added selenium which was performed on glucose substrate with varying concentrations and forms of selenium. Selenium was applied in a form of sodium selenite Na2SeO3 and sodium selenate Na2SeO4. Numerous experimental repetitions suggest a significantly important effect of the form of the added selenium on growth rate and vitality of Chlorella sp. While the algae did not thrive on sodium selenite medium, they prospered on sodium selenate and exhibited faster growth compared to that on the media without additional selenium.

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