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Episodic like memory in nonhuman animals
Gálik, Michal ; Landová, Eva (advisor) ; Vlček, Kamil (referee)
Episodic memory refers to an ability that allows a person to mentally re-enact past events from his own life. This capacity was long considered to be uniquely human. The best evidence of this ability in humans is subjective consciousness, which accompanies episodic recollection. For this reason, it is particularly difficult to study such cognitive ability in other animal species. However, there is some indirect evidence showing that animals could possess the ability of episodic memory to some degree. This bachelor thesis summarizes recent knowledge about episodic memory, provides an overview of specific studies in different animal taxons and compares the methodologies used by various authors to demonstrate episodic memory in animals. It focuses mainly on birds, rodents and primates. KEYWORDS : Episodic memory, Episodic-like memory, Hippocampus, Cognitive ability, Animal model
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Induction of neurogenesis and gliogenesis after ischemic injury of CNS
Filipová, Marcela ; Moravec, Jan (referee) ; Anděrová, Miroslava (advisor)
Ischemic injury (stroke) is one of the most common causes of death and disability in humans. Discovery of adult neurogenesis and possibilities to induce neurogenesis by cytokines brought new approaches and hopes in treating the ischemic lesion in future. The aim of this thesis is to describe cellular and molecular mechanisms of neurogenesis, mainly those discovered within last ten years. The first part describes generation of new neurons in the brain under physiological conditions, which is localized in the dentate gyrus of the hippocampus and in the subventricular zone of the lateral ventricles (i.e. in principal neurogenic regions). The second part describes animal models used for studying ischemic injury in rodents and moreover, it focuses on patophysiology of ischemic brain injury, which is accompanied by astrocyte and microglia activation. Further, the ischemia-induced neurogenesis is described in these two major neurogenic regions. Also the important role of NG2 glial cells in central nervous system (CNS) regeneration is pointed out. According to recent findings NG2 glia that are present in all regions of CNS might serve as a potential source of cells for directed differentiation into oligodendrocytes, astrocytes and even neurons during CNS repair/regeneration. In the last part of this work,...
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The role of glucocorticoids in circadian system
Tejkal, Karel ; Sumová, Alena (advisor) ; Forman, Martin (referee)
Glucocorticoids are mammalian steroid hormones secreted from the adrenal gland. The basal levels of glucocorticoids show a pronounced diurnal rhythm with maximum at the beginning of the active period and minimum at its end. Glucocorticoids have an influence over a variety of metabolic functions and their secretion is tightly regulated. This regulation also depends on the circadian system, which utilizes glucocorticoids to entrain the peripheral tissues by inducing rhythmic gene expression. The mechanisms by which glucocorticoids influence mammalian circadian system has not yet been precisely defined, especially concerning the influence of glucocorticoid signalling on gene expression in different tissues and the dynamics of glucocorticoid receptor (GR) occupancy. This thesis studies the influence of ablation of glucocorticoid signalization induced by adrenalectomy on the clock gene expression of in the central clock in the suprachiasmatic nucleus and peripheral clocks in the hippocampus and distal colon. The effect of adrenalectomy on gene expression is compared with the effect of restricting the feeding time, which has also been shown to affect glucocorticoid levels in the body. Other experiments were aimed at elucidating impact of changing the activity of GR on gene expression using synthetic GR...
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Analysis of volumetric change of Hippocampus caused by Alzheimer's disease
Pham, Minh Tuan ; Harabiš, Vratislav (referee) ; Walek, Petr (advisor)
Interest in hippocampus increased sharply after his significance in the process of learning and retention of information was published. In particular, considerable interest was in its volume changes and their effect on Alzheimer’s disease. Understanding the structure and function hippocampus would contribute to a more accurate diagnosis of this disease. In this work was created a method of hippocampal segmentation using active contours. With its help, the data composed of both healthy and a diseased patients was segmented and the results were then statistically analyzed using statistical methods such as Kruskal-Walis test, Mann-Whitney test. The level of significance given by results of analysis supports alternative hypothesis that attaches significance of the difference in volume of the hippocampus between studied groups.
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International trade in sea horses (\kur{Hippocampus spp}.)
NEDOROSTOVÁ, Anna
This work comprehensively reviews the international trade in sea horses, particularly the Hippocampus genus, from 1997 to 2012. The genus was added to the Appendices II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (thereinafter as the CITES) in 2002, came into force in 2004. Before the addition, the genus was entered into the appendix D for the non-CITES species whose import is monitored by the EU. The CITES Trade Database kept by the UNEP - WCMC Secretariat was used as the source of data about the trade. The frequency of the trade in sea horses tended to be increasing with a moderate decrease in 2009. The Hippocampus species was traded in the following forms: live, bodies, derivatives, specimens, medicine, carvings, eggs live, extracts, fingerlings, powder, skeletons, skin pieces, soup, trophies and other unspecified forms. The living specimens traded: (1) specimens taken from the wild., (2) animals bred in captivity as well as parts and derivatives, (3) Animals born in captivity (F1 or subsequent generations) that do not fulfil the definition of 'bred in captivity', as well as parts and derivatives thereof, (4) specimens of animals reared in a controlled environment, taken as eggs or juveniles from the wild, where they would otherwise have had a very low probability of surviving to adulthood, (5) confiscated or seized specimens, (6) pre- Convention specimens. The trades purposes were: (1) commercial, (2) personal, (3) scientific, (4) zoo (aquarium) breeding, (5) educational, (6) breeding in captivity, circus and other exhibitions, (7) conventional medicine, (8) law enforcement / judicial / forensic purposes. The most traded genus was unspecified (Hippocampus spp.), then the H. kuda, the H. reidi and the H. erectus as living specimens or dead bodies; also the ones from the wild and for the commercial purposes. Those came mostly from Vietnam, Thailand or Australia. They were exported mainly from Indonesia, Sri Lanka and Australia. The greatest importers were the USA, Germany and the Great Britain.
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Comparison of diagnostic yield of different MRI protocols and PET in relation to time an finance demands in patients with temporal epilepsy
FILÍPKOVÁ, Brigita
This Thesis called Comparison of diagnostic yield of different MRI protocols and PET in relation to time and finance demands in patients with temporal epilepsy deals with time and economic aspects of diagnostics of pharmacoresistant temporal epilepsies. Temporal epilepsies are the most frequent focal epilepsies (up to 85 %) and pharmacologic control is only successful in about 25 % cases. On the other hand it is the best type of epilepsy to be solved surgically. Timely and precise diagnostics enables a timely surgical intervention. The time and economic demands increase the same way as the demands for technical staff. The Thesis was aimed at finding a protocol advantageous in terms of both, time and cost saving, maintaining the diagnostic yield in comparison of two neuroimaging methods - functional (PET) and morphological (MR), where we also compared two protocols for brain examination - a standard one and a special epileptological one. Methodology: A retrospective study of 44 patients with clinically confirmed focal epilepsy examined by MR and PET, who underwent a microsurgical intervention and have been without fits since then. We compared the individual protocols on MR - standard (sequence T2/PD tse tra, FLAIR tra, T2* tra and T1 se sag) and epileptological (extended by 3DT1 ge, T2 tse fs cor and FLAIR cor) in terms of possible diagnostics (examination read by an experienced radiologist) and evaluated their time and cost demands. We also evaluated a PET examination, which is performed by one protocol, the same way. The results demonstrate the difference in examination time and costs between the standard and the epileptological protocols on MR and between the MR and PET methods. There are also results of reading MR and PET images and their correlates presented there. We may conclude that the epileptological protocol on MR cannot be substituted by a standard protocol. Time may be saved by better organization of work or by suitable adjustment of parameters of the individual sequences maintaining sufficient MR image quality. We are also convinced that both the methods, MR and PET are important for safe diagnosis. Cost saving is impossible in pre-operation diagnostics.
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