National Repository of Grey Literature 85 records found  beginprevious44 - 53nextend  jump to record: Search took 0.00 seconds. 
Ability of copper chelators to interact with iron and zinc
Hanuščinová, Lucia ; Mladěnka, Přemysl (advisor) ; Čonka, Patrik (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Lucia Hanuščinová Supervisor: Assoc. Prof. Přemysl Mladěnka, PharmDr., PhD. Title of diploma thesis: Ability of copper chelators to interact with iron and zinc Copper plays in the human organism a role of an element with indispensable significance, whose biological influence and effects depend on its quantity. With elevated concentrations in the human body, copper becomes toxic, resulting in pathological conditions. The most well-known diseases is the Wilson's disease, whose treatment consists of oral administration of chelators, i.e. chemical compounds, which are capable of binding copper ions in various proportions and eliminating them from the organism. Chelation therapy is currently the first choice after confirmation of the diagnosis. Chelation toxicity results from several factors, e.g. inhibition of copper dependent enzymes or low selectivity to metals. And precisely the selectivity of chelators is being discussed in this diploma thesis. An ideal chelator should not interact with any of the other physiological ions, that are necessary for the proper functioning of the organism. Five of the most frequently therapeutically or experimentally used substances /trientine, D-penicillamine,...
Ability of copper chelators to interact with iron and zinc
Hanuščinová, Lucia ; Mladěnka, Přemysl (advisor) ; Čonka, Patrik (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Lucia Hanuščinová Supervisor: Assoc. Prof. Přemysl Mladěnka, PharmDr., PhD. Title of diploma thesis: Ability of copper chelators to interact with iron and zinc Copper plays in the human organism a role of an element with indispensable significance, whose biological influence and effects depend on its quantity. With elevated concentrations in the human body, copper becomes toxic, resulting in pathological conditions. The most well-known diseases is the Wilson's disease, whose treatment consists of oral administration of chelators, i.e. chemical compounds, which are capable of binding copper ions in various proportions and eliminating them from the organism. Chelation therapy is currently the first choice after confirmation of the diagnosis. Chelation toxicity results from several factors, e.g. inhibition of copper dependent enzymes or low selectivity to metals. And precisely the selectivity of chelators is being discussed in this diploma thesis. An ideal chelator should not interact with any of the other physiological ions, that are necessary for the proper functioning of the organism. Five of the most frequently therapeutically or experimentally used substances /trientine, D-penicillamine,...
Bioaktivní látky ve vodním prostředí a jejich vliv na ryby - zaměření na cytochromy P450 v rybách
SAKALLI, Sidika
The term "biologically active compounds" covers a wide range of substances originating from natural or synthetic origins. These compounds can enter the aquatic environment through wastewater treatment plants, manufactural discharge or they are naturally present in the aquatic plants or microorganisms. Their adverse effects on fish has been widely studied and accepted. This thesis is focussed on the adverse effect of several bioactive compounds (i.e. pharmaceuticals, phytochemicals, or complex mixture of pollutants) on fish using different experimental design as in vitro, in vivo and in situ. In the first part of this thesis, in vitro effects of pharmaceuticals and phytochemicals or their combinations on fish CYP system were investigated. Moreover, effects of standard carrier solvents used in enzyme activity assays were also investigated. An important finding in this study was the lack of effects of either dexamethasone, quercetin, or indole-3-carbinol on EROD activity; however, when these agents were combined, EROD activity was strongly inhibited. This demonstrates that combination of compounds might exert different effects than single compounds, and the effects of mixture compounds cannot be predicted from the effects of individual compounds. In the second part of the thesis, the effects of chronic exposures of rainbow trout to dexamethasone and clotrimazole were investigated. The results regarding dexamethasone showed similarities with in vitro studies, and both in vitro and in vivo exposure of dexamethasone did not alter the CYP enzyme activities. On the other hand, in vivo exposure of clotrimazole yielded conflicting results with findings from the in vitro studies. Clotrimazole induced EROD activity in chronically exposed rainbow trout, and BFCOD activity showed biphasic pattern in which it was inhibited at environmentally relevant concentrations and induced at high concentrations. Thus, the observed effects suggest that clotrimazole could negatively affect fish CYPs at environmentally relevant concentrations. However, in the environment, the effects of clotrimazole and dexamethasone on fish CYPs system might be modified because of unknown compounds in these mixtures. Therefore, further investigations were done to identify the effects of mixture compounds using an in situ model. The last part of the dissertation addresses the effects of cocktail PPCPs on common carp under natural conditions. In situ studies provide valuable information on both hepatic and intestinal CYP activities. Both EROD and BFCOD activities were affected by the PPCPs that are present in the exposed fish. Moreover, changes in intestinal CYP activities suggest that fish can ingest some of these contaminants through their feed. Therefore, the intestines might be responsible for elimination of some of these pollutants and act as the first barrier of pollutant entry in fish. Despite the extensive studies concerning aquatic pollution, further studies are necessary. Development of new pharmaceuticals, their occurrence in the aquatic environment, and their effects on non-target organisms should be continuously monitored.
Sun protection factors determination for cosmetic emulsions
Slechanová, Veronika ; Jugl, Adam (referee) ; Smilek, Jiří (advisor)
The bachelor thesis deals with the anatomy and physiology of the skin, ultraviolet rays, sunscreens and current methods used to measure the value of sun protection factor. One of the goals of the thesis is to get the overview of the UV filters currently widely used in cosmetic products and giving them the required protection against the sun. The obtained knowledge was subsequently used for the determination of the sun protection factors in selected sunscreens by in vitro methods. The measurement provided satisfying results comparable with the values given on the label of the tested products. However, it is still necessary to optimize the methodology even more in order to obtain data with lower deviations and especially with much higher reproducibility.
The in vitro effects of selected substances on isolated rat aorta
Beránková, Anna ; Pourová, Jana (advisor) ; Vopršalová, Marie (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Anna Beránková Supervisor: PharmDr. Jana Pourová, Ph.D. Title of diploma thesis: The in vitro effects of selected substances on isolated rat aorta Flavonoids are a numerous group of secondary plant metabolites. Flavonoid compounds are substances widely extended in nature and many of them have a positive influence on human health, primarily for their vasodilatory, antioxidant and anti- inflammatory effects. Three substances were selected for this diploma theses: two substances of isoflavonoid group, genistin and genistein, and the end product of genistein metabolism, 4-ethylphenol. The aim of this work is examination of vasorelaxant effects of this substances in vitro. Vasorelaxing potential of tested substances was tested in vitro in isolated aortic rings of Wistar rat. The effect of increasing doses of individual substances in precontracted aortic rings with intact endothelium was measured. From the obtained values of vessel tension, the DRC curves and EC50 values were created. The results were evaluated. The results analysis shows, that genistein (EC50 2,903.10-5 M) had the most significant activity. Also genistin (EC50 4,045.10-4 M) and high doses of 4-ethylphenol (EC50 1,509.10-3 M) caused...
The role of dietary haemoglobin in physiology and development of \kur{Ixodes ricinus} nymphal stage
HATALOVÁ, Tereza
Obligatory blood feeding ensures consistent composition (both molecular and cellular) and provides a comprehensive source of nutrients. Ticks imbibe host blood meal in their all active stages. For that reason, they were hypothesised to loose some biosynthetic pathways at the expense of developing acquisition and transporting networks. Availability of genomic and transcriptomic data of Ixodes spp. ticks revealed that they have lost genes encoding enzymes, participant in haem biosynthesis. Using an artificial membrane feeding system of hard ticks, it was demonstrated that adult I. ricinus females acquire haem from a host haemoglobin and transport extracted haem into ovaries. Ovaries devoid of host haem deposits failed to undergo embryogenesis and halted tick reproduction. Questions how juvenile stages of ticks require haem and for what purposes is a focus of this bachelor thesis.
Cytotoxicity testing on 2D and 3D model of human liver cells
Hvolková, Simona ; Ramos Mandíková, Jana (advisor) ; Bárta, Pavel (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Simona Hvolková Supervisor: PharmDr. Jana Ramos Mandíková, Ph.D. Title of diploma thesis: Cytotoxicity testing on 2D and 3D model of human liver cells. An inherent part of drug development are in vitro assays, which might be helpful in prediction of drug toxicity. Nowadays, the majority of assays use simple 2D structures for cell growth, but 3D structures with similar conditions to in vivo are becoming more popular. The goal of the study was to assess the cytotoxicity of selected xenobiotics in vitro by both 2D and 3D cell models. The research subjects were drugs from the group of antimycotics (amphotericin B, ketoconazole), NSAIDs (diclofenac, ibuprofen), antipyretics (paracetamol, fenacetine), sodium azide, tamoxifen, para-aminosalicylic acid, methanol and ethanol. For determination of cytotoxicity, the standard colorimetric method (CellTiter 96® ) based on reductive assessment of metabolic active cells was used. For drug testing it was used human standard line of liver cells HepG2. The cells were cultivated in monolayer or in 3D form with the Alvetex® Scaffold technology using high porous networked polystyrene. The parameter of inhibition concentration IC50 was chosen for toxicity assessment of...
Využití kultivačních médií pro množení banánovníku metodou in vitro
Kadlecová, Eliška
This work deals with characterization of Musa genus, in vitro cultivation of banana plants and micropropagation of three chosen Kluai Namwa cultivars. Theoretical part comprises of genus Musa taxonomy and particular groups in this genus, then description of all the parts of banana plant, origin of banana growing and cultivars. The world most important cultivars were chosen and described together with their occurence. This chapter includes description of importance and different usage of bananas and world banana trade, too. There can be found overview of the most important pests and diseases of banana plants, ways of multiplication and advantages and difficulties of breeding. The part named Banana plant in vitro deals with specific uses of different aseptic cultures of bananas, it describes some of used practises and their risks. This chapter focuses mostly on micropropagation of banana plants, from establishing the culture to weaning and planting to the field. Third and last part describes the experiment with multiplication of three banana cultivars from Kluai Namwa group (ABB). This experiment took place at Thai university in the year 2015. The goal was to evaluate the suitability of four different cultivation media for individual cultivars and to suggest the best medium for multiplication. Two solid MS media were tested (one with the BA concentration 3 mg.l -1 , the second with 5 mg.l -1 BA) and two liquid MS media with the same concentrations of BA. As the best medium for all three cultivars it turned out to be the liquid one with 5 mg/l BA. But even when this media was used the proliferation of new shoots was low. As the solution the use of fructose as source of energy and multiplication in TIS were sugested.
Preparation and characterization of diamond-based nanocarriers for transfection of siRNA
Majer, Jan ; Cígler, Petr (advisor) ; Fišer, Radovan (referee)
Although nanodiamonds were discovered and produced tens of years ago, they have been utilized in medical and biological fields just recently, particularly in drug and gene delivery into a cell and in bioimaging methods. Nanodiamonds can be modified with specific positively charged moieties for complexation with negatively charged nucleic acids. These complexes afterwards overcome extracellular and intracellular barriers and transport the nucleic acid either into cytosol or into the nucleus. Owing to fluorescence centres nitrogen- vacancy, which can be formed in the nanodiamonds, nanodiamonds exhibit excelling optical properties, as they emit stable fluorescence without "photoblinking" or "photobleaching". This thesis reviews properties, synthesis and modifications of nanodiamonds and other selected nanoparticles and their in vitro applications. This thesis also compares their cytotoxicity and gene knockdown efficiency.
Proteins as a source of nitrogen for tobacco plants grown in vitro
Bělonožníková, Kateřina ; Ryšlavá, Helena (advisor) ; Entlicher, Gustav (referee)
Nitrogen (N) belongs among necessary elements for plant growth and development. In the past attention was paid mostly to the inorganic forms - nitrate and ammonium. In soil N is also present in organic forms, including proteins, for which plants could compete with soil microorganisms. Recently two ways have been considered - the hydrolysis of proteins by secreted proteases and endocytosis of native proteins, possibly their confluence. Tobacco plants were grown in vitro under sterile conditions in modified Murashige-Skoog medium with casein as the only source of N (CAS), decreased concentration of inorganic forms of N (AD) or in complete Murashige-Skoog medium as control plants (MS). After the 12 weeks growth, the standard growth parameters were measured. The CAS plants were able to grow without inorganic N, and protein content in the leaves was higher than in other experimental plants. Proteomic analysis documented differences in protein expression in plant roots in the dependence on the form of N. In total 185 proteins were identified, 75% of proteins were less and 14% more abundant in the CAS plants. The uptake of casein conjugated with fluorescein was followed and the proteolytic activity was analyzed by confocal microscopy. Among proteins secreted from roots to the medium aspartic protease...

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