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Sample preparation for analyzing oligomeric forms of amyloid beta by mass spectrometry
Mrkvičková, Simona ; Cvačka, Josef (advisor) ; Kozlík, Petr (referee)
Alzheimer's disease is the most widespread chronic and progressive neurodegenerative disease. The main problem of the disease is the reduction and damage of nerve cells. This leads to loss of brain mass and memory impairment. The disease mainly affects the elderly, for whom it is the most common cause of dementia. Around 50 million people suffer from this disease worldwide, and the number is growing. Alzheimer's disease thus represents a serious public health problem. The pathogenesis of this disease is controlled by the production and deposition of amyloid beta peptide. This peptide tends to aggregate. Its lower oligomeric forms are water-soluble and have a toxic effect on nerve cells. Amyloid beta oligomers therefore represent a possible target for the diagnosis of Alzheimer's disease. Oligomeric forms of beta amyloids have a non-covalent character, which can negatively affect their stability during analyzes in model and biological samples. In this bachelor thesis, suitable conditions for the preparation of model amyloid beta samples were sought. It was observed how the distribution of oligomeric forms changes under the influence of solvents, salts and other additives. The effect of pH on the incubation of amyloid beta in ammonium acetate and water was also investigated. Finally, a method for the...
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Mercury contents in mushrooms growing nearby Horní Slavkov
Říhová, Štěpánka ; Svoboda, Lubomír (advisor) ; Tondl, František (referee)
In the seventies it was discovered, that many species of wild higher fungi accumulates in their fruiting bodies some potentially hazardous elements in amounts significantly higher, than any other ecosystem cells, respectively eatables. For the most risky elements especially cadmium and mercury are considered. The aim of my rigorous paper was to determine mercury content in the fruiting bodies of mushrooms growing in the area with an extremely rich history of mining and processing of metal ores (mostly tin). Mushroom samples were collected (from July 2005 to September 2006) from two sites near the village of Krásno close Horní Slavkov. Mercury was analyzed in 130 samples of 13 edible mushroom species. Only fully developed fruiting bodies were selected for the analysis, each represented a separate sample. It was also carried out a comparative test, detecting effect of fungal cleansing on the kontent of mercury. Mercury was determined in homogenized samples on a single-atomic absorption spectrometer AMA -254, which uses the technique of atomizing cold vapor generation of mercury with subsequent capture on a gold amalgamator. The content of mercury in the fruiting bodies of the monitored area was very well comparable to the normal state in areas without mining. In point of harmful character of mercury,...
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Toxic smoke in the burning of selected substances, detection and protection intervening fire
ŠEBA, Jaroslav
Toxic products of combustion released by selected substances {--} their detection and the protection of firefighters I have opted to focus my Bachelor paper on this subject on the strength of my 20 years of working at the law-enforcing department of Fire Rescue Service; consequently, I am well aware of the difficulties that the firefigthers meet in their attempts at obtaining vital information. I have decided to investigate the subject and offer the results so that the fireman units could be properly trained. The paper is divided into several sections. The first aims to find out to what extent the units of the South Bohemian Fire Rescue Service are equipped with detection devices; the second examines the options of protection available to the firefighters in action; and the third section pays attention to the current standards of training given to the firefighting units deployed in the regional Service. The fourth section contains a comprehensive chapter on the noxious products of combustion, presenting available information on substances most often released in their burning. The next section provides a questionnaire survey designed to map the knowledgeability of firefighters and, to permit comparisons, also the awareness that the general public has of the substances and the toxicity of their combustion products. The chapter included to present evaluations and analyses starts with a description of materials to be ignited. The products of their burning were gathered using the Tenax tubes to be later analyzed in the laboratory. The lab analysis results are presented together with the major effects that the substances may have on human body. With the questionnaire survey evaluated, it became obvious that the firefighters were considerably better informed than the general public in all areas thus surveyed. Still, the incorrect answers returned by the freighters testify to a great deal of deficiencies that the system of training should address and regular training sessions of units should remedy. Excellent results were obtained for firefighters in action, since in most cases their level of protection was found higher than what was actually necessary. The level of knowledge encountered in the general public respondents proved to be below the average. Their awareness of hazards that the combustion products may pose for humans should be heightened (e.g. through a campaign able to provide information on the subject) since the products may be detrimental to the health of just anybody.
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