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New findings of physiological and ecological aspects of hibernating bats
Ungrová, Zdislava ; Jahelková, Helena (advisor) ; Lučan, Radek (referee)
Bats can be found in almost all climatic zones. They have to deal with unfavorable conditions of environment to survive and reproduce sucessfully. Especially in temperate zones they have to deal with cold temperatures and lack of food during a winter season. To save energy bats enter a short, diurnal torpor or a hibernation. Usually, hibernation lasts all winter and is disturbed by short bouts of arousals. During both hibernation and torpor a physiological changes occur in bodies of bats. Body temperature decreases from endothermic levels, metabolic rates are reduced as well as respiratory rate and pulse. These changes are mainly influenced by weight and body size, diet, ambient temperature, sex and reproductive status. With the developement of new technologies, these changes can be measured more accurately than they have been in past, whether in a field or in a laboratory. But not all physiological processes are well explained. We have little knowledge especially about mechanism of arousal from hibernation. During awakening bats are infected by fungus Geomyces destructans that affects their immune system. In Norh America fungus causes a disease called White- Nose syndrome (WNS), that is responsible for death of millions of bats, especially endangered is Myotis lucifugus. In Europe, this disease is reffered...
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Metabolism of uric acid during mammalian evolution
Mančíková, Andrea ; Krylov, Vladimír (advisor) ; Stibůrková, Blanka (referee)
Uric acid is the end product of purine metabolism of humans and some higher primates. In other mammals enzyme urate oxidase is capable to further convert uric acid to allantoin. During evolution of primates several mutations in urate oxidase gene had occured, led the enzyme to decrease its activity or to complete loss of function. What was the initial impetus for the utilization of uric acid and what biochemical traits of uric acid led to a tendency to retain a major of this metabolite production in the bloodstream? Uric acid has antioxidant capabilities and it is scavanger of free radicals. Increased levels of uric acid in blood has an effect on acute and chronic elevations of blood pressure. It is possible that hyperuricemia helped to maintain blood pressure under low-salt dietary conditions of primates during the Miocene. This mechanism probably have allowed to stabilize bipedalism our ancestors. Uric acid has an important role as a neuroprotector. As inhibitor the permeability blood-brain barrier, uric acid limits the infiltration of undesirable substances to the neurons and prevents central nervous system against the formation of inflammatory diseases. Such as neurodegenerative diseases may be caused by reduced serum uric acid levels. Uric acid protects against peroxinitrite damage tissues in the...
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Effects of chemopreventive compounds on cytochrome P450s
Křížková, Jitka ; Hodek, Petr (advisor) ; Helia, Otto (referee) ; Václavíková, Radka (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Science Department of Biochemistry Effects of chemopreventive compounds on cytochrome P450s Summary of Ph.D. Thesis RNDr. Jitka Křížková Supervisor: prof. RNDr. Petr Hodek, CSc. Prague 2010 Introduction 1 Introduction According to the World Health Organization statistics, cancer is one of the leading causes of death in the human population worldwide for more than 50 years. Moreover, colorectal and gastrointestinal tract cancers are one of the main types of cancer leading to overall cancer mortality. Prevention consisting in a healthy lifestyle and a natural diet is suggested to be one of the main approaches to reduce cancer risk. In recent years, the consumption and use of dietary supplements containing concentrated chemopreventive phytochemicals increased dramatically. Flavonoids, as the most popular representatives of chemopreventive compounds, present in foods (fruits, vegetables, herbs, beverages) and dietary supplements have the potential to modulate the activity of xenobiotic-metabolizing enzymes [Hodek et al., 2002]. Among proteins interacting with flavonoids, cytochrome P450s (CYPs), monooxygenases metabolizing xenobiotics (e.g. drugs, carcinogens), play the most prominent role. The two members of CYP1A subfamily, CYP1A1 and CYP1A2, are involved in the...
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Phytoremediation:biochemical characteristics of heavy metal hyperacumulators
Lábusová, Jana ; Lipavská, Helena (advisor) ; Podlipná, Radka (referee)
Water and soil pollution by heavy metals is a very serious problem of nowadays. Since the beginning of industrial revolution, the concentration of heavy metals increased sharply in the environment. One way how to decontaminate soils and groundwaters is phytoremediation that uses plants to remediate pollutants from the contaminated sites. This eco-friendly and cost- effective method exploits the ability of plants to take up, translocate, transform and sequester metals. In phytoremediation, the plants that are able to accumulate metals to high concentration are mainly used. These plants are named "hyperaccumulators". Accumulation of metals by plants is affected not only by the capability of plant in question, but to a great extend also by the form and concentration of metal in the soil and environmental conditions. The aim of this Bachelor thesis is to summarize knowledge on impact of heavy metals on biochemical changes in plants, with special emphasis on changes in carbohydrate metabolism.
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Determination of aluminium concentration changes in infusion and digesta of Hibiscus sabdariffa
Binderová, Denisa ; Potůčková, Miroslava (advisor) ; Blanka, Blanka (referee)
The aim of this bachelor thesis was to characterize aluminium content in infusion and digestate of Hibiscus sabdariffa tea. Dried Hibiscus is worldwide used for the manufacture of herbal or fruit tea. Aluminium is at excessive exposure toxic for human organism. The amount of this element which is human gastrointestinal tract able to intake and absorb depends on many factors such as the form of it, physico-chemical properties of a food matrix and on their behavior in the human gastrointestinal system. The concentration of aluminum in the dried plant matrix is influenced bythe ability of plant to accumulate element from the soil and create aluminium complexes in tissues. This process protects plant against aluminium toxicity.
In experimental part of bachelor thesis was determined the amount of aluminum in dried plant matrix of 8 herbal teas of hibiscus flower, their infusions and digestates by emission spectrometry with inductively coupled plasma (ICP-OES). Digestates from infusions were prepared according to the current version of the static in vitro gastrointestinal model Infogest Working Group. The content of the element in plant matrix was not (p < 0.05) effect by the type of agricultural production (conventional × ecological) or country of origin. From dried hibiscus flowers passed only cca 5 % of aluminium into the infusion and this amount was not (p < 0.05) proportional to the initial content of element. There was a statistically significant (p > 0.05) increase in the concentration of aluminium after infusions digestion via simulated gastrointestinal process. The observed increase of aluminum content was probably caused by the acidic pH of the gastric phase of digestion where aluminium passed into well soluble and therefore better absorbable forms.
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Analýza metabolických a reprodukčních ukazatelů ovcí ve vybraném chovu plemene suffolk
OUŘEDNÍKOVÁ, Kateřina
The aim of the study was to analyze the reproductive, productive and metabolic values of ewes from selected parameters in blood, milk and urine in correlation to their metabolic state. The results were used to draw up new breeding and feeding schemes. The research was carried out in 2015, and the sample size consisted of 62 Suffolk ewes. The analysis of reproductive parameters of selected ewes confirms appropriately chosen breeding methods. The average weight of lambs at birth (3,82 kg) is affected by the number of lambs at birth. The average weight of lambs at 100 days of age (32,54 kg) depends on the number of lambs per ewe and the age of ewe. The average daily weight gain makes 0,325 kg per lamb. Lowered concentration of proteins related to the decreased level of urea in the blood plasma signifies insufficient intake of nitrogen of ewes from feed.
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Milk composition as an indicator of the metabolism of dairy cows
ŠTĚRBA, Lukáš
Milk presents good marker metabolic levels in dairy cows. Subscribe milk in moreover to cow does not stressful. Each month has a breeder in the yield control available basic data on milk composition (fat, protein, lactose). This basic data can be expanded to include other parameters (milk urea, ketones and citric acid). Based on these milk parameters can then correct interpretation preventively diagnose metabolic diseases in the herd. In this work, based on yield controlling diagnosed with high metabolic burden herd Haklovy Dvory. In March 2014, according to the results of the composition of milk probably 33,3% of dairy cows exposed to challenges from acidogenic burdens and 15,2% negative energy balance. In April, was then exposed to challenges from acidogenic burdens 37,8% of herds and negative energy balance 26,7% of the herd. For selected cows are then carried out an analysis of the metabolic state based on milk composition and biochemical blood tests. Milk always signaled higher metabolic burden cows associated with the appearance of serious metabolic diseases (acidogenic burdens) than blood. Diagnosis of rumen acidosis of the blood is not simple and milk, this could serve as a useful indicator of the current state of the acid-base balance in the rumen.
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The thyroid gland activity of sheep
DŘÍZHALOVÁ, Blanka
In the theoretical part of my thesis, I describe the thyroid, its importance, anatomy, creation of hormones and their regulation. There is also summarized the knowledge of external environment influences on the thyroid such as nutrition, climatic conditions or seasons and internal factors influences, mainly breed, efficiency and age. The practical part is focused on the evaluation of the thyroid activity of free-range ewes and lambs in the spring and autumn of 2013. The thesis also deals with the evaluation of possible relevance between the content of thyroid hormones in the blood serum and the physiological state of the sheep. Thanks to the correlation between TSH and thyroid hormones, the proper regulation of the thyroid of ewes and lambs was confirmed. The thyroid activity was higher in the spring than in the autumn. The hypothyroidism in the autumn was not proved because no referential values of TSH are set. In the autumn there was a lower level of glucose and cholesterol in the blood of the ewes determined which gives evidence of a lower energy income from the feed in the autumn. Also the urea level which is closely connected to the energy shortage, starvation, and high income of N substances in the feed dosage was in the autumn twice as high as in the spring. There was a positive correlation determined between the higher urea concentration and the higher thyroid activity. Owing to the change of the feed content, the TSH started to stimulate the thyroid to a higher thyroid hormones production and thus to its higher activity.
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Zinek jako esenciální mikronutrient
Hádler, Tomáš
In the first part of these presented bachelor thesis are described general characteristics of zinc, it's occurence in enviroment and it's history. Next part described effect of this element on human health (specific health risks associated with its deficiency), transport and its general role in the metabolism, further discussed. There are summarized recommendations for zinc daily intake. A major part of this thesis is focused on the zinc content in various types of foods. A main part of the thesis is concerned with zinc deficiency and symptoms of zinc deficiency for the living organisms. The following part described selected foods and their zinc content. A very substantial part of the work is the possibility of fortification of foods with zinc, as well as supplementation. Last but not least, the zinc metabolism is described and it's availability for human body. Some analytical methods for the determination of zinc in food and other biological samples are described.
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Výskyt kvasinek v silážích a jejich význam
Vaculíková, Barbora
The aim of the study was to assess the effect of yeast in silage and verify the fact that the additives will ensure inhibition of undesirable microorganisms. The literature review focused on the metabolism of yeast, their importance in silages limitations and possibilities. Model experiments were performed with peas with barley silage and with corn silage. The influence of additives on the final quality of the silage and their influence on the content of microorganisms, together with the quality of the fermentation process, was assessed. According to the provided measurements it can be argued that the use of additives was only partly due to the limitations of yeast and aerobic stability. Chemical preservatives based on organic acids favorably slowed the onset of secondary fermentation in peas with barley silage, even though there was no suppression of the number of yeast on this option. The negative correlation of yeast dry matter content was confirmed for the corn silage (r= 0.6219). In the silage with a chemical preservative (2,402 +- 0,775 log CFU/g) positive effect (P<0,05) on the limitation of yeast compared was detected to the control silage. Based on measurements of pH the degree of contamination of yeast cannot be evaluated. It was confirmed that even the best additive cannot guarantee quality and stable silage, if the principles of silage are not adhered to.
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