National Repository of Grey Literature 9 records found  Search took 0.00 seconds. 
Elucidating the source of bloodstream \kur{Trypanosoma brucei} mitochondrial ATP
HUSOVÁ, Michaela
For decades, it has been assumed that the reduced function and structure of the bloodstream form Trypanosoma brucei mitochondrion renders it a strictly ATP consuming organelle. Emerging evidence from refocused studies suggest that the bloodstream mitochondrion retains complex bioenergetic pathways that allow the parasite to adapt to various environments. This thesis is focused on the source of bloodstream mitochondrial ATP, with a special emphasis on the role of succinyl-CoA to produce ATP via mitochondrial substrate phosphorylation. We will also discuss alternative bioenergetic pathways present in this life stage of a human pathogen.
Dýchání spermií ryb: druhová specifičnost a vliv teploty prostředí
RAHI, Deepali
The presented studies were designed to investigate the role of mitochondrial respiration, glycolysis, and fatty acid oxidation in the energy supply of spermatozoa in freshwater, externally fertilizing fish species possessing differences in sperm motility duration and spawning temperature. The first study conducted on Siberian sturgeon (Acipenser baerii, Acipenseriformes) revealed that mitochondrial respiration is essential for the energy supply of spermatozoa, while glycolysis and fatty acid oxidation have minor importance at both states - before and after attaining motility. Spermatozoon oxygen consumption rate (OCR) was higher than one detected for coldwater teleosts, such as trout, and lower than in marine species, for example, turbot. The presented study also revealed that sturgeons belong to the group of fishes whose spermatozoa possess the capacity to enhance oxidative metabolism after motility activation and uncoupling of oxidative phosphorylation (OXPHOS). In the second study conducted on spermatozoa of coldwater species burbot (Lota lota, Gadiformes), the functioning of the most important bioenergetic pathways (mitochondrial respiration, glycolysis, and fatty acid oxidation) was investigated at spawning temperature (4 °C) and maximum critical temperature (CTmax, 15 °C). At spawning temperature, similar to the results revealed for Siberian sturgeon spermatozoa, the role of glycolysis and fatty acid oxidation in energy supply was insignificant. Mitochondrial respiration was detectable at both quiescent and motile states, but no inhibition was observed after exposure of sperm to the respiratory inhibitor. Also, the OCR range was the lowest compared to the available data for OCR in teleost spermatozoa at motile or immotile state. Additionally, the OCR was not enhanced after motility activation or after treatment with an uncoupling agent. Contrastingly, at CTmax, the activity of OXPHOS became predominant. The OCR was enhanced, and that could be inhibited by using a respiratory inhibitor. Furthermore, to explore the long-lasting motility of sturgeon spermatozoa, succeeding steps were taken by studying the phosphocreatine-creatine (PCr-Cr) shuttle system apart from the previously studied pathways - OXPHOS, glycolysis, and fatty acid oxidation. The results obtained for sterlet (A. ruthenus, Acipenseriformes) revealed that PCr-Cr shuttle, known for maintaining a homogenous concentration of ATP molecules throughout the flagellar length, plays an active role while spermatozoa are at a quiescent state. No significant contribution of this shuttle in energy supply after sterlet sperm motility activation was detected. In addition to this, presented results also revealed that sturgeon spermatozoa, similar to carp and trout sperm, can be reactivated after the termination of the first motility period, and these secondly activated spermatozoa can successfully fertilize eggs. Moreover, for the first time, it was revealed that OXPHOS and PCr-Cr shuttle systems are the most crucial bioenergetic pathways during the sperm reactivation process. Overall, it was concluded that in the studied fish species, despite taxonomical differences or varying spawning temperature , sperm energy production and utilization strategy remained the same: most of the spermatozoon energy was derived from stored ATP that had been synthesized via OXPHOS during a quiescent but bioenergetically active state. Also, sturgeons are the group of fishes that possess an ability of sperm reactivation, with mitochondrial respiration and PCr-Cr shuttle system being the major contributing pathways for energy supply during reactivation process.
Verification of a 4 min all out test as a reliable indicator of sport climbers finger flexors critical force
Taušl, Pavel ; Baláš, Jiří (advisor) ; Gajdošík, Jan (referee)
Title: Verification of a 4 min all out test as a reliable indicator of sport climbers finger flexors critical force. Objectives: The aim of this study was to assess the reliability of an 4 min all-out test which determines climbers finger flexors critical force. Methods: 6 participants did a 4 minute all out test to determine their finger flexors critical force. Afterwards, they did several verification tests with +2, -2, -4 and -6 kilograms added or deducted from their crtical force for 12 minutes or until failure, where their maximal metabolic steady state should be observed based on muscle oxygenation and subjective intensity control. Results: 4 climbers have reached their maximal metabolic steady state. 2 of them reached it at 4 kilograms below their critical power and 2 of them reached it at 6 kilograms below their critical power. 2 climbers did not make another verification measurements. Conlcusion: 4 minute all-out test overestimated critical power by 26 % at a given population. Key words: spectroscopy, maximal metabolic steady state, sport climbing, climbing performance.
MR spectroscopy in patients with diabetes mellitus
Šedivý, Petr ; Štěpánková, Helena (advisor) ; Roztočil, Karel (referee)
This thesis deals with in vivo MR spectroscopy. Measurements in this thesis were performed on whole-body MR tomograph at the Institute for Clinical and Experimental Medicine in Prague. The objective of the thesis was to study differences in the biochemical processes and energy metabolism in the muscle tissue under physical workload between the groups of healthy subjects and patients with type 1 diabetes mellitus (DM1). We used phosphorous spectroscopy in combination with ergometer. The thesis is divided into five chapters. The first chapter describes theoretical introduction to in vivo 1 H and 31 P MR spectroscopy and muscle metabolism, the second chapter deals with the description of the experimental equipment and measurement, results of the thesis are reported in the third chapter and the fourth chapter is a discussion of results. Main result of this work is summarized in conclusion; we found differences between the metabolism of patients with DM1 and healthy volunteers.
The role of mitochondrial energy metabolism in cell senescence
Zima, Michal ; Trnka, Jan (advisor) ; Pecinová, Alena (referee)
Cellular senescence represents status, when the cells cease to divide and remain in permanent cell cycle arrest. Senescence is considered to be an active response of the cell to various extrinsic and intrinsic types of stress such as certain oncogene activation, exposing to several cytokines or drugs and damaged and/or uncapped telomeres. Senescent cells are characterised by extensive modification of gene expression, flattened and enlargement of cellular body. Hypothetically, altered gene expression may lead also to increase of certain surface proteins expression. Such protein can be L1 cell adhesive molecule (L1CAM), which is expressed heterogeneously within the population. This Thesis describes current knowledge of cellular senescence, the mechanism, which may result in establishment of senescence phenotype, and also the characteristic markers of senescence. Thesis also puts together the heterogeneity of L1CAM expression in A375 senescent cells with oxygen consumption rate and extracellular acidification rate performed by Seahorse XFe24 metabolic analyser. Therefore, ells were sorted according to their levels of expressing L1CAM onto low and high L1CAM expressing subpopulations. Obtained data show potential correlation between the rate of L1CAM expression in A375 cells and the metabolic rate. Key...
The role of mitochondrial energy metabolism in cell senescence
Zima, Michal ; Trnka, Jan (advisor) ; Pecinová, Alena (referee)
Cellular senescence represents status, when the cells cease to divide and remain in permanent cell cycle arrest. Senescence is considered to be an active response of the cell to various extrinsic and intrinsic types of stress such as certain oncogene activation, exposing to several cytokines or drugs and damaged and/or uncapped telomeres. Senescent cells are characterised by extensive modification of gene expression, flattened and enlargement of cellular body. Hypothetically, altered gene expression may lead also to increase of certain surface proteins expression. Such protein can be L1 cell adhesive molecule (L1CAM), which is expressed heterogeneously within the population. This Thesis describes current knowledge of cellular senescence, the mechanism, which may result in establishment of senescence phenotype, and also the characteristic markers of senescence. Thesis also puts together the heterogeneity of L1CAM expression in A375 senescent cells with oxygen consumption rate and extracellular acidification rate performed by Seahorse XFe24 metabolic analyser. Therefore, ells were sorted according to their levels of expressing L1CAM onto low and high L1CAM expressing subpopulations. Obtained data show potential correlation between the rate of L1CAM expression in A375 cells and the metabolic rate. Key...
MR spectroscopy in patients with diabetes mellitus
Šedivý, Petr ; Štěpánková, Helena (advisor) ; Roztočil, Karel (referee)
This thesis deals with in vivo MR spectroscopy. Measurements in this thesis were performed on whole-body MR tomograph at the Institute for Clinical and Experimental Medicine in Prague. The objective of the thesis was to study differences in the biochemical processes and energy metabolism in the muscle tissue under physical workload between the groups of healthy subjects and patients with type 1 diabetes mellitus (DM1). We used phosphorous spectroscopy in combination with ergometer. The thesis is divided into five chapters. The first chapter describes theoretical introduction to in vivo 1 H and 31 P MR spectroscopy and muscle metabolism, the second chapter deals with the description of the experimental equipment and measurement, results of the thesis are reported in the third chapter and the fourth chapter is a discussion of results. Main result of this work is summarized in conclusion; we found differences between the metabolism of patients with DM1 and healthy volunteers.
The legacy of Wilhelm Reich and its reflexion in the work of the founders of Bioenergetics, Biosynthesis and Biodynamic Psychology
Vaněčková, Marta ; Pivoňková, Věra (advisor) ; Hroníková, Linda (referee)
The diploma thesis The legacy of Wilhelm Reich and its reflexion in the work of the founders of Bioenergetics, Biosynthesis and Biodynamic psychology is devoted to a comparison of the most important theoretical concepts and therapeutic techniques of Wilhelm Reich with the methods of the founders of selected psychotherapeutic approaches that draw from his work. These are the founder of Bioenergetics Alexander Lowen, founder of the Biosynthesis David Boadella and founder of Biodynamic Psychology Gerda Boyesen. These authors created distinct therapeutic approaches based on Reich's concepts that significantly shaped the field of the Body- Psychotherapy. The first part explains the technique of Character-Analysis and Vegetotherapy, the Orgasm Theory (the role of sexuality in the etiology of neurosis), a typology of Character structures, the Orgonomic Research and principles of the Orgonomic Functionalism, which Reich defined and used in practice. There is briefly introduced the history of the development within the Neoreichian movement (Reich pupils and followers) in the second half of the 20th century. The vast majority of the second part of the thesis is devoted to reflection on Reich's work in the selected body-psychotherapeutic schools and the way they work with his legacy. The Bioenergetics is...
Effect of ski-mountaineering equipment on energy expenditure of skiing
Smětáková, Martina ; Baláš, Jiří (advisor) ; Jindra, Matouš (referee)
Title of master thesis Effect of ski-mountaineering equipment on energy expenditure of skiing. Work objectives The aim of this study was to determine the effect of weight ski equipment energy performance when walking on snow. Methods The study included 6 skialpinists a mean age of 30 ± 5.5 years. Energy intensity was measured on the basis of breathe oxygen (VO2) and exhaled (VCO2). The measurements were used 3 types of ski-hiking equipment (light - medium x 3160 g - 7754 g x heavy - 9600 g). Each test first completed section in a time of 6 minutes flat terrain (0ř), after which he immediately set out to climb the 360 m long route at an angle (20ř). These two sections (0ř and 20ř) graduated in random order for each type of equipment and at a constant speed of 1 m·s-1 . Results The results show that energy intensity decreases significantly when using ultralight ski equipment. We found that the climb at an angle of 20ř is the difference in oxygen consumption (VO2) between moderate and light equipment 9.6% between heavy and light equipment 17.7% and medium-heavy and heavy equipment 7,4%. The average VO2 test with light equipment was 44.4 ± 3.7 ml·kg-1 ·min-1 , with moderate equipment 48.7 ± 5.6 ml·kg- 1 ·min-1 and heavy equipment 52.2 ± 4.8 ml·kg-1 ·min-1 . At 0ř inclination and moderate use of heavy...

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