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Tracking the progression of Alzheimer's like-pathology in transgenic rat model TgF344-AD
Foltýnová, Alice ; Telenský, Petr (advisor) ; Němec, Pavel (referee)
Alzheimer's disease (AD) is a progressive neurodegenerative disorder affecting dominantly the elderly and it is the most common cause of dementia. AD is characterized by many pathological events such as amyloid plaques, neurofibrillary tangles, inflammation, neurotransmitter dysregulation and many others. These disruptive processes ultimately lead to synaptic and cell loss which human brain. According to literaure, cell loss in AD is apparent especially in the cortex and hippocampus. However, it is unclear at which timepoint the loss becomes significant and in which other structures. There are many other important structures such as olfactory bulbs or entorhinal cortex where the cell loss has not been fully quantified. With new methods like isotropic fractionator it has become possible for scientists to quantify large number of structures more quickly. Since human brains are not easy to obtain shortly after death, use of transgenic animal models, mostly rodents, is a good way to obtain more information about cell and especially neuronal loss occurring in AD. Key words: Alzheimer's disease, cell loss, isotropic fractionator, hippocampus, neurofibrillary tangles, beta amyloid
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Cerebral laterality in birds and mammals, its behavioral correlation and evolutionary significance
Tureček, Petr ; Komárek, Stanislav (advisor) ; Němec, Pavel (referee)
Lateralization of brain is ubiquitous quality of vertebrate brain. In this paper we rewiev examples of brain lateralization in birds and mammals and it's behavioral impacts. Than we discuss possible evolutionary origins of these asymmetries and their evolutionary significance. We try to explain individual as well as population level lateralization. We propose, that population level lateralization can, in principle, arise just on the genofondal basis, if the organism itself contributes to the enviroment with the lateralized behavior. Lateralized sensory input on the other hand should stand on the advantages of synchronizing with other individuals due to the disatvantage of predictability of lateralized population. Keywords: Lateralization; laterality; population level lateralization; asymmetry; evolutionary significance
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Magnetic orientation in mammals
Tejmlová, Kristýna ; Němec, Pavel (advisor) ; Vácha, Martin (referee)
Earth's magnetic field can provide animal with both directional and positional information. The ability to perceive and utilize information extracted from the geomagnetic field is called magnetoreception. Magnetoreception mechanisms remain largely unknown. Three main hypotheses are currently supported by experimental evidence. The light-independent mechanisms are based either on electromagnetic induction or on biogenic magnetite. The light-dependent mechanism is based on specific chemical reaction between radical pairs. Perception of the geomagnetic field facilitates both long- and short-distance orientation of animals. Some animals exhibit the magnetic alignment, i.e., spontaneuos preference for a certain geomagnetic direction. Another manifestation of magnetoreception is magnetic compass (polarity- or inclination-based, depending on species), which enable an animal to determine the azimuth, i.e., the angle between the direction of motion and geomagnetic field vector. Magnetic map sense enable an animal to determine its position and direction to the goal destination, most likely utilizing the inclination and the intensity of the geomagnetic field as navigational cues. Magnetic orientation of mammals seems to be a widespread phenomenon. Light- independend, polarity compass has been reported in...
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Factors affecting oetrous cycles in the house mouse (Mus musculus)
Havrdová, Leona ; Stopka, Pavel (advisor) ; Němec, Pavel (referee)
Factors affecting oetrous cycles in the house mouse (Mus musculus) Abstract This bachelor thesis deals with factors which have significant influence on house mouse (Mus musculus) oestrous cycle. Main theme is oestrous cycle modulation caused by male or female chemical signals. Familiar phenomena like Bruce effect, Whitten effect and Lee-Boot effect are described in detail along with newly explored social modulation issues (ovulation trigger, male genotype role etc.). Environmental impact is also included, especially role of Bisphenol A in connection with negative impacts on human reproduction (tested on mice). Key words: oestrus, pheromone, MUP, Mus musculus, vomeronasal organ
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Neural crest biology with respect to diversity of vertebrates
Štundl, Jan ; Černý, Robert (advisor) ; Němec, Pavel (referee)
Neural crest is an extensively migrating population of cells that arise during early development of vertebrate embryos. It provides a huge variety of different cell types that generate new tissues which occur only in vertebrates. Neural crest cells together with the mesoderm participate on the formation of the head of vertebrates, which is viewed as one of the most important innovations in the evolution of vertebrates. Thanks to their skeletogenic potencial neural crest cells are percieved as a key factor causing massive craniofacial diversity. The aim of this thesis was to get acquainted with the population of neural crest cells and try to understand its importance for the evolution of vertebrates and especially for generating craniofacial diversity.
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The role of vent genes family in early development and brain development
Fabian, Peter ; Kozmík, Zbyněk (advisor) ; Němec, Pavel (referee) ; Balaštík, Martin (referee)
6 III ABSTRACT (ENGLISH) In chordates, the central nervous system (CNS) is derived from the dorsal part of gastrula. Induced dorsal part of the embryo - the neural plate - gives rise to the neural tube or primordial brain. The developing dorsal part of the embryo is shaped by BMP/Smad signaling from the ventral part. Using the basal chordate amphioxus, we show here the conserved evolutionary role BMP/Smad signaling in axial cell fate determination. Pharmalogical inhibition of BMP/Smad signaling induces dorsalization of Branchiostoma floridae (amphioxus) and Oryzias latipes (medaka) embryos and expansion of neural plate markers. We provide evidence for the presence of the positive regulatory loop within the BMP/Smad signaling network of amphioxus. Thus, our data suggest that early emergence of a positive feedback loop within the BMP/Smad signaling network may represent a crucial molecular event in the evolutionary history of the chordate cell fate determination. The dorso-ventral body axis formation is mediated by genes of the vent family, which are the direct targets of BMP/Smad signaling. The function of vent gene family in early development is relatively well known, however, its role in developing CNS is not yet clear. Therefore, we decided to manipulate vox transcription factor, a vent family member....
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Methodological aspects of active place avoidance task
Bahník, Štěpán ; Stuchlík, Aleš (advisor) ; Němec, Pavel (referee)
The active place avoidance task represents one of the methods of the study of animal cognition. In this task, a subject is put on a rotating circular arena and avoids invisible sector that is stable with respect to the room. Rotation of the arena means that the subject's avoidance must be active, otherwise the subject would be moved in the punished sector by the rotation of the arena and a slight electric shock would be administered. The experiment described in the present work explored the effect of variable arena rotation speed on the ability to avoid the punished sector. Rats in a group with a variable arena rotation speed learned to avoid the punished sector with the same speed and attained the same ability to avoid the sector as rats in a group with a stable arena rotation speed. The only difference between the two groups was found in a preferred position within the room. No difference was found between the two groups in the dark phase, where the rats could not use orientation cues in the room. Only one rat was able to learn the avoidance of the punished sector in this phase. The results of the experiment suggest that idiothetic orientation and interval timing are not crucial for learning of the avoidance of the punished sector. However, idiothetic orientation is sufficient for the avoidance of the...
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Immediate early genes as a tool for study of spatial orientation and memory
Bláhová, Veronika ; Němec, Pavel (advisor) ; Telenský, Petr (referee)
Properties of the environment, spatial orientation cues and time-shifting movements are essential for cognitive maps. The understanding of how both space and the animal's position within that space are represented in the brain has been significantly advanced by the discoveries of four principal neuronal types: the place cells, the head direction cells, the grid cells and border cells. Their activity being driven by both allothetic (visual and non-visual landmarks), and idiothetic cues (internal movement cues based on proprioceptive and vestibular information). Brain regions containing aforementioned types of neurons constitute complex spatial representation system. Immediate early genes (IEGs) and their products became sophisticated tool for the study of neural substrate of spatial orientation including magnetic orientation. For further research it is unavoidable to uncover the dynamic of processes related to IEGs in order to better understanding the functions of brain centres involved in rodent navigation circuit. This work summarises our knowledge about spatial orientation of the vertebrates aimed at rodents, in context with detection of IEGs expression as activity markers in neural substrate. There are described most common experimental mazes and most frequent detection methods used in connection with...
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Enamel cover of the mammalian teeth: structural, functional, developmental and phylogenetic aspects.
Hanousková, Pavla ; Horáček, Ivan (advisor) ; Němec, Pavel (referee)
Specificities of the mammalian teeth and their enamel coat with particular re- spect to the autapomorphies establishing the mammalian organization. Basic structural and organizational levels of the enamel histology (nanocrystals, elementary crystallites, prismatic enamel, IPM, schmelzmuster, ultimate characteristics of particular dentitions). Basic survey of comparative data: characterization of enamel of mammals in particular clades and a brief summary of their specificities. Concluding remarks on current state of knowledge and per- spectives of further study. 1
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Missa chrismatis and Its Changes in the Twentieth Century: A Comparison of Changes in Liturgy and Theology
Němec, Pavel ; Kotas, Jan (advisor) ; Opatrný, Aleš (referee)
Missa chrismatis and Its Changes in the Twentieth Century: A Comparison of Changes in Liturgy and Theology. Missa Chrismatis (Chrism Mass) is a Mass that the bishop celebrates in the Holy Week, together with his priests, which is a sign of mutual unity. During this Mass, the priests renew their priestly vows and the bishop consecrates the oil of catechumens, the oil of the sick and the chrism oil. The ceremony underwent several changes over the past century. These are reflected also in the theology, expressed in the liturgy by emphasizing of certain elements. The major reforms of the liturgy of the Mass took place in several stages in the 50`s, 60`s and 70`s of the 20th century. First, the thesis follows the basics and reasons for the use of oils in the liturgy of the Catholic Church in the context of Easter and then the historical development of the Mass, in which the oils are consecrated. Also it clearly compares the progress of the Missa chrismatis liturgy and captures differences in the liturgical texts and texts of the rite of benediction of oils in the various phases of the reform of the twentieth century. On this basis, it attempts to render the evolution in theological content. Keywords Missa Chrismatis, Benediction of Holy Oils, Chrism, The Holy Week, Maundy Thursday, Liturgical Reform.
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