National Repository of Grey Literature 22 records found  beginprevious13 - 22  jump to record: Search took 0.01 seconds. 
Efficiency of Water Treatment Processes Using Activated Carbon
Hladíková, Lucie ; Kolesíková, Lucie (referee) ; Kučera, Tomáš (advisor)
The subject of the thesis is the issue of pesticides in the environment and the possibility of their removal through activated carbon. The thesis is divided into two parts, the search part and the practical part. The research part is focused on description of activated carbon. It also deals with the distribution of pesticides and their degradation in the environment. In the practical part, a laboratory experiment was carried out to determine the effectiveness of removing pesticides and metabolites from the test water on two types of activated carbon.
Disposition of New Synthetic Drugs in The Organism. Pharmacokinetics and Biotransformation Study. Toxicological Detection in Biological Materials.
Židková, Monika ; Balíková, Marie (advisor) ; Šustková, Magdaléna (referee) ; Šanda, Miloslav (referee)
The object of this thesis was the study on the pharmacokinetics and biotransformation of selected abused new synthetic drugs, specifically belonging to cathinone and aminoindane groups, in experimental rats. This work consisted of two parts: a biotransformation study of mephedrone, methylone, 5,6-methylenedioxy-2- aminoindane (MDAI) and a distribution profile study of mephedrone, methylone, MDAI and naphyrone. This document is presented as a commentary to the original papers, which were published in peer reviewed journals. The samples of blood and tissue (brain, lungs, liver) were taken at specific times after a subcutaneous single bolus dose of the studied drugs. The urine samples for the biotransformation studies were collected over a 24-hour period following the sc. dose. The LC/HRMS method was used for metabolite detection and quantitative analysis. Our findings not only included testing metabolites of the aforementioneddrugs against the synthesized reference standards, but also discovering previously unknown metabolites of these drugs. Ten phase I and five phase II metabolites aside from the parent drug were identified in urine after mephedrone administration by comparison of their spectra against those of reference standards and/or MS2 spectra of previously identified metabolites. The main...
Aplikace pokročilých přístrojových technik pro analýzu polutantů životního prostředí
KOBA, Olga
Increasing of human life comfort and safety requires development and application of new chemical substances, which, unfortunately, cannot be completely removed by WWTPs. Thus, these compounds, their metabolites and TPs formed during human/animals/bacteria metabolism, wastewater treatment and natural environmental processes are tend to contaminate all the environmental compartments. Appearance of advanced analytical instrumentation and techniques enable to perform research on emerging environment contaminants fate. This thesis was focused on application of high resolution mass spectrometer and new generation of triple quadrupole for analysis of the environmental pollutants. All studies were mainly devoted to such a group of contaminants as pharmaceuticals because of their high consumption, frequent occurrence in all environmental matrices and potential to cause adverse effects for non-targeted organism due to their biological activity. The first part of the thesis is related to method development for identification and quantification of metabolites in the different tissues of rainbow trout exposed to diltiazem. As a result, 17 diltiazem metabolites were tentatively identified by HRMS and spectral interpretation software. The complex metabolic pathway in metabolic phase I for diltiazem and tissue specific bioconcentration in fish were proposed in the study. The second part of the work is mainly focused on investigation of pharmaceuticals fate in the soil environment. The transformation of several pharmaceuticals, such as atenolol, metoprolol, carbamazepine, sulfamethoxazole, trimethoprim, and clindamycin in 13 different soils was studied under laboratory conditions. The parent compounds were analyzed in all studied soils and dissipation curves were plotted. Finally, 15 known and new metabolites were detected and identified. Moreover, identity of 6 of them was confirmed by available analytical standards. It was shown that almost the same metabolites profile was observed in all soils, but formed amount and degradation rate of all detected metabolites were soil type dependent. Several parent compounds and metabolites were shown to be persistent in the soils. Consequently, pharmaceuticals can be transported via ground water to plant. Further fate of pharmaceuticals must be studied as it can have adverse effect on crop consumers. The third part of the dissertation dealt with an important issue of pharmaceuticals transport between different aquatic environmental compartments. Water, sediments and fish from a pond affected with TWW from a local WWTP were analyzed within this project. 18 pharmaceuticals and 7 their metabolites were found in all studied matrices. Solid water distribution coefficients for sediments and bioaccumulation factors for fish liver were obtained in this study under real conditions. Seasonal variations in all studied parameters were investigated for one year period. This study help to extend a limited available information on fate of wide range of compound, especially metabolites in the aquatic environment affected by treated wastewater.
Enzymatic modifications of bioactive flavonoids
Rydlová, Lenka ; Tesařová, Eva (advisor) ; Wimmer, Zdeněk (referee)
Extract from milk thistle (Silybum marianum (L.) Gaertn., synonym Carduus marianus L., Asteraceae) silymarin contains among others primarily bioactive flavonolignans. They have hepatoprotective and antioxidative effects and also anticancer, chemoprotective, dermatoprotective and hypocholesterolemic activity. This thesis focuses on the preparation of metabolites of the second phase of biotransformation unexplored flavonolignans 2,3-dehydrosilybin (DHSB), silychristin (SCH), 2,3-dehydrosilychristin (DHSCH). Pure sulfated derivatives were prepared using aryl sulfotransferase from Desulfitobacterium hafniense and p-nitrophenyl sulfate (p- NPS) as a donor. Flavonolignans yield exclusively monosulfates at the position C- 20 (C-19 in the case of silychristin and 2,3-dehydrosilychristin), except for 2,3- dehydrosilybin that gives also the 7,20-disulfated derivatives. For all samples were made antioxidant tests - DPPH assay (the highest activity had 2,3-dehydrosilychristin sulfate: IC50= 7,87 µM), Folin-Ciocalteau reduction assay (the highest activity had 2,3-dehydrosilychristin: 1,58 ekvivalents of gallic acid), ABTS+ scavenging (the highest activity had silychristin: 1,50 ekvivalents of vitamin C), inhibition of microsomal lipid peroxidation (the highest activity had 2,3-dehydrosilybin: IC50 = 10,6 µM),...
HPLC Determination of Benzimidazoles
Slezáková, Šárka ; Kubíček, Vladimír (advisor) ; Lázníčková, Alice (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of biophysics and physical chemistry Candidate: Šárka Slezáková Supervisor: Ing. Vladimír Kubíček, CSc. Title of diploma thesis: HPLC Determination of Benzimidazoles In this thesis we have investigated the possibility of establishing benzimidazole with HILIC chromatography using a chromatographic column Ascentis Express HILIC 10.0 cm x 3.0 mm; 2.7 microns. Two groups of benzimidazoles were tested. The first one was focused on albendazole and its metabolites. Experiments with these substances did not produce satisfactory results, because the mobile phase composition which enables separation of the studied analytes was not found. The second group was formed by flubendazole and its reduced and hydrolyzed form. In this case, several mobile phase compositions were tested. Finally, distribution of individual analytes in a mixture, using a mobile phase ACN:HCOOH 0.03 mol/l (90:10), was successfully achieved. Ricobendazol was chosen as an internal standard. When separation conditions were found, calibration curve for the determination of reduced flubendazole in biological samples was subsequently constructed using ricobendazol as the internal standard with the use of fluorescence detection. Keywords: HILIC, HPLC, albendazole,...
HPLC determination of silybin diastereoisomers in plasma of laboratory animals
Kolářová, Petra ; Tesařová, Eva (advisor) ; Bednář, Petr (referee)
Silybin is the main component of silymarin, a standardized extract obtained from the seeds of milk thistle (Silybum marianum). Flavonolignan silybin has antioxidant, hepatoprotective, chemoprotective and antitumor activities. Natural silybin occurs as an approximately equimolar mixture of two diastereoisomers - silybin A and silybin B. Analytical separation of these diastereoisomers is possible but preparative separation is complicated. The biological activity of the silybin A is different from the silybin B. Silybin diastereoisomers are mainly conjugated to glucuronides and sulfates in organism. A mixture of both silybin diasteroisomers is used in the majority of reported biological, chemical and pharmacokinetic studies. For the first time, optically pure silybin A and silybin B were used for pharmacokinetic study in this thesis. The object of this work was determination of the concentration of free and total silybin in rats plasma in relation to time. Theoretical introduction describes the current state of the problem of chemistry, pharmacology and pharmacokinetics of silybin diastereoisomers. Second part is focused on the selection of appropriate analytical column, chromatographic method and suitable procedure for preparation of biological samples for the determination of the silybin...
Overview of methods used in plant physiology for primary and secondary compounds estimation
Dlouhý, Lukáš ; Tomášková, Ivana (advisor) ; Čepl, Jaroslav (referee)
This bachelor thesis aims to summarize methods used to prove and isolation substances of primary and secondary metabolism of plants. In introduction I described metabolit path ways leading to creation of metabolites and introduced their definitions. In next chapters I pursued closer description of each group and sub-group of metabolites and specified options of their qualitative analysis. In last part I continued to outline issues of separation methods, instrumental analysis and finaly to experiments. In conclusion I summarized obtained information generaled comparison of each method or their groups. I estimated the trend of analysis for trees and plants.
The effect of metabolite terbuthylazine-2-hydroxy on early life stages of marbled crayfish
PEŘINOVÁ, Eliška
Terbuthylazine belongs to the group of pesticides on triazine-based for use in agriculture as herbicides. Terbuthylazine-2-hydroxy is the main metabolite of terbuthylazine. The aim of this study was evaluate the effect of terbuthylazine-2-hydroxy on mortality, growth, occurrence the deformations and the development of early life stages, and levels of oxidative stress, assess the activity of antioxidant enzymes of marbled crayfish (Procambarus fallax f. virginalis) and also augment data for assessing the impact of this metabolite on the environment. For assess of effect of this metabolite was used embryo larval toxicity test with crayfish. The effect of terbuthylazine-2-hydroxy was evaluated in four concentrations (0.75 g.l-1, 75 g.l-1, 375 g.l-1 and 750 g.l-1) for 62 days. Terbuthylazine-2-hydroxy in concentrations 375 g.l-1 and 750 g.l-1 caused decrease of activity superoxide dismutase (SOD) and the levels lipid peroxidation (measured as TBARS) and inhibition of growth. Inhibition of growth was also observed in the group exposed to 75 g.l-1 of terbuthylazine-2-hydroxy. Additionally, there was delay in ontogenetic development of crayfish exposed to concentration 750 g.l-1. The real tested concentration of 75 g.l-1 terbuthylazine-2-hydroxy had no effect to monitored indices in the early life stages of marbled crayfish. Terbuthylazine-2-hydroxy caused oxidative damage of cellular lipids and proteins, changes in antioxidant activity, reduction of growth, delay in ontogenetic development of marbled crayfish.
Vliv vybraných kardiovaskulárních léčiv nalézaných ve vodním prostředí na ryby
STEINBACH, Christoph Antonius
Cardiovascular pharmaceuticals are among the most prescribed drugs. As a result of the high consumption, these pharmaceuticals have been frequently detected in waste and surface waters. Verapamil, diltiazem and atenolol are very important representatives of cardiovascular pharmaceuticals; therefore, the present research focused on their acute and sub-chronic effects, bioconcentration, half-life time and metabolism in fish. Moreover, unified protocol for the quantitative assessment of histopathological alterations on the heart ventricle and coronary blood vessels employing heart index calculation was developed with the aim to better assess histopathological changes in fish heart which is one of the targets of cardiovascular pharmaceuticals and other chemicals. The effects caused by high concentrations of the studied substances, verapamil, diltiazem and atenolol, in fish can be considered similar to the therapeutic effects and side effects that are found in humans. The acute exposure to verapamil at the human therapeutic plasma level reduced the heart rate in common carp embryos and larvae. In addition, the acute and chronic exposure to this substance caused peripheral edema and gastrointestinal haemorrhage in carp. Similarly, the histological changes in heart and the blood vessels of the liver in diltiazem exposed rainbow trout suggested vasodilatation similar to the pharmacological effect of diltiazem in the human body. In rainbow trout sub-chronically exposed to atenolol at a human therapeutic blood plasma concentration, histopathological changes in the cardiovascular system were found. The bioconcentration of verapamil, diltiazem and atenolol in fish can be classified as low. Bioconcentration factor (BCF) of verapamil in whole body homogenates of common carp ranged between 6.6 and 16.6. The BCF of diltiazem was also relatively low (0.5-194) in analysed tissues of trout, following the order kidney liver muscle blood plasma. BCF of atenolol in rainbow trout tissues was the lowest among the tested substances (BCF = 0.002-0.27), following the order of liver > kidney > muscle. In the blood plasma, the concentration of atenolol was below the limit of quantification. Verapamil showed a longer half-life time (10.6 days) in fish compared to the human body, indicating the slow rate of biotransformation and/or elimination of verapamil in fish. Estimated half-life times of diltiazem in liver (1.5 h) and kidney (6.2 h) were in the same order of magnitudes as those determined for the human blood plasma. The half-life time of atenolol in trout was not studied, because of its very low bioconcentration. In diltiazem exposed rainbow trout, 8 groups of metabolites of diltiazem with 17 different isoforms were identified using liquid chromatography/high resolution mass spectrometry method. Diltiazem was found to undergo a biotransformation involving desmethylation, desacethylation and hydroxylation in fish. These results showed that diltiazem was metabolised in fish in a similar way like in the human body by desmethylation and desacethylation. On the other hand, hydroxylation, which was involved to a minor extent, seemed to be species specific. Verapamil had no effect on early life stages of common carp at the environmentally relevant concentration after one month lasting exposure. On the other hand, atenolol and diltiazem in environmentally realistic concentrations caused after 42-day exposure some physiological changes in rainbow trout. Namely, atenolol affected haematological and biochemical parameters of the blood in exposed rainbow trout and diltiazem caused changes in the activity of antioxidant enzymes in trout liver and gills. These data indicated that atenolol and diltiazem, when present in the aquatic environment, could be a source of sub-lethal detrimental effects in fish.

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