National Repository of Grey Literature 50 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
The ex vivo effects of selected silymarin flavonolygnans on isolated rat aorta
Sloukgi, Tatiana ; Pourová, Jana (advisor) ; Mladěnka, Přemysl (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Tatiana Sloukgi Supervisor: PharmDr. Jana Pourová, Ph.D. Title of Diploma Thesis: The effect of Silymarin Flavonolignans and their sulfated conjugates on blood vessels ex vivo. Silymarin flavonolignans have recently shown some positive effects on the cardiovascular system. In this work, we studied the vasodilatory effect on rat aorta ex vivo of three silymarin conjugates, silybin A-20-sulfate, silybin B-20-sulfate and 2,3- dehydrosilychristin-19-O-sulfate, and one parent flavonolignan 2,3- dehydrosilychristin. For each substance, a concentration response curve was created and the concentration that produces 50% of maximum relaxation was determined (EC50). All substances exerted very low or no vasodilatory activity. Finally, we focused on the mechanism of action of silybin A. We tested whether its vasorelaxant activity depends on the presence of intact endothelium. The vasorelaxant effect of silybin A on isolated rat aorta ex vivo was clearly endothelium-dependent.
Social behavior and communication in a laboratory rat and autism models
Tučková, Klára ; Petrásek, Tomáš (advisor) ; Pohanová, Petra (referee)
Social behavior of the brown rat as an animal living in a hierarchical collonies is very diverse and developed, which remains the same with the domestic laboratory rat. Rats communicate not only via odors, but also via various types of vocalizations, which express stress, pain or anxiety or on the other hand positive emotions and also communication during any social contact. Because of complex social behaviour and communication, rat is a suitable model organism for research of human mental disorders such as autism. This thesis gives an overview of natural social behaviour of rats, behavioural methods used for testing of animal models and describes selected rat models of autism induced through various types of interference (natural mutation, gene inactivation, virus infection and chemical disruption of brain development) and compares their impact at the level of rat behaviour. Key words Rat, social behaviour, communication, vocalization, experimantal tasks, model organism, autism, models of autism
Antioxidant system in hypoxic heart
Sotáková, Dita ; Žurmanová, Jitka (advisor) ; Kalous, Martin (referee) ; Babula, Petr (referee)
The cardiovascular disease, particularly acute myocardial infarction, is the most common cause of death worldwide. It is well documented that adaptation to chronic hypoxia increases resistance to ischemia-reperfusion (I/R) injury in heart tissue. Reactive oxygen species (ROS) play an important signalling role by the activation of the protective pathways during I/R, although, the excess of ROS during reperfusion leads to cardiac tissue injury. As the cellular antioxidant system is responsible for the maintenance of redox homeostasis, the main aim of this thesis was to investigate the relationship between myocardial tolerance to I/R injury and regulation of main components of antioxidant systems, related transcription factors and their target genes in protective and non- protective regimens of chronic hypoxia. We found differences in cardioprotective phenotype in rats exposed to three regimens of chronic normobaric hypoxia (FiO2 0.1, 3 weeks). The adaptation to continual (CNH) and intermittent (CNH-8; 8 h/day) regimen of hypoxia increased myocardial resistance to I/R damage, whereas 1-hour daily interruption of hypoxic adaptation (INH-23) abolished cardioprotective effect and decreased the ratio of reduced and oxidized glutathione (GSH/GSSG). Both cardioprotective regimens significantly increased...
The establishment of invariable behaviour of rats in novel one-trial trace association task (OTTAT)
Alexová, Daniela ; Stuchlík, Aleš (advisor) ; Telenský, Petr (referee)
Animal episodic-like memory tasks represent important component of episodic memory research. However, currently available episodic-like memory tasks are not based on episodic-like memory or encompass important caveats. In our laboratory, we recently devised a novel one-trial trace association task (OTTAT) to examine one-time associations of temporally discontinuous stimuli. This thesis deals with the improvement of OTTAT protocol by rat strain and compartment divider ('doors') selection which optimally promote the establishment of invariable behaviour of rats in OTTAT. Moreover, the accuracy of one-trial associations is also assessed by determining specificity of "rapid escape" response to conditioned stimulus of given sound characteristics. In Experiment 1, rats (Sprague-Dawley (SD), n = 36; Wistar (WI), n = 17; Long-Evans (LE), n = 8) were habituated 15 min daily for 3 days with standard doors (9 x 11 cm opening) to modified light and dark apparatus. The number of transfers between compartments and values of time spent in dark compartment obtained from 3rd habituation session were evaluated as indicators of invariable behaviour of rats. We found WI rats spend significantly more time in dark compartment than LE (p = 0.002) and SD rats (p = 0.001) and have significantly fewer transfers than LE rats...
The in vitro effects of selected fenolic substances on isolated rat vessels
Rajtmajerová, Iveta ; Pourová, Jana (advisor) ; Hrdina, Radomír (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Iveta Rajtmajerová Supervisor: PharmDr. Jana Pourová, Ph.D. Title of diploma thesis: The in vitro effects of selected fenolic substances on isolated rat vessels Silymarin flavonolignans are endowed with various aspects. Recently their hepatoprotective effect has been discussed widely as well as their positive influence on the cardiovascular system. This diploma thesis is concerned with the vasodilatory effects of silybin-A, silybin-B, silybin-A + B and isosilybin-A on rat aorta. The aim of this study was to test the vasodilatory effect of selected substances. The dependence of aortic relaxation on the increasing concentration of tested substances was measured. Isolated Wistar breed rat aorta was used. DRC curves were created and EC50 values were assessed from the obtained values of vessel tension. The results were evaluated subsequently. The vasodilator potential of silybin-A and isosilybin-A is comparable; hence the position of the substituents may be irrelevant in having any impact on relaxation of the vessels. Different vasodilatory effects of silybin-A and silybin-B have been observed thus, the relaxation could be stereoselective. The testing of the equimolar mixture of silybin-A and...
Cardioprotective effect of adaptations to hypoxia and cold: Connexin 43 and hexokinase 2
Kohútová, Jana
Ventricular arrhythmias are the main cause of death worldwide. An increased incidence of arrhythmias in the heart of mammals is accompanied by a remodeling of the cellular distribution gap between the channels of mainly connexin 43 (Cx43). Recently has been demonstrated significant effect of mitochondria and their association with arrhythmogenesis. Various pathological conditions alter the expression and / or distribution of Cx43, depending on the phosphorylation status. but also on altering the association of hexokinase with mitochondria, which reduces the likelihood of apoptosis activation. Adaptation to intermittent hypobaric hypoxia potentiates endogenous pathways reducing the incidence of ventricular arteries, whereas continuous normobaric hypoxia does not have this effect. Another studied model is cold acclimatization, which has been known for several decades by known effects on human health. However, the heart study of these models in relation to Cx43 is missing. Our goal was to determine the expression of Cx43, phosphorylated Cx43 (p-Cx43) and hexokinase (HK1, HK2) and their distribution in cardiomyocytes. In addition, the expression of Cx43 upstream kinases, protein kinase A, protein kinase G, casein kinase 1 in normoxic and hypoxic left ventricles of rats, along with Cx43 distribution...
The effect of morphine withdrawal on the adenylyl cylclase signaling system in rat brain
Nováková, Daniela ; Novotný, Jiří (advisor) ; Rudajev, Vladimír (referee)
The aim of this bachelor thesis is to study the effect of morphine withdrawal on the adenylyl cyclase signal system in the rat brain. Theoretical part of this thesis summarizes basic information known about opioids and its leading representative morphine, molecular mechanisms of its effect on the organism and yet determined knowledge about effects of morphine addiction and subsequent withdrawal on the organism and above all on the central nervous system. There is still much unknown about exact mechanism of development of morphine addiction and withdrawal. This thesis also summarizes briefly the Western blot method used in analysing the effect of morphine withdrawal on selected proteins of the adenylyl cyclase signal system in the rat brain. Experimental part of this thesis is based on the detection of expression of key components of the adenylyl cyclase pathway in selected regions of the rat brain after long-term administration and subsequent withdrawal of increasing doses of morphine. Results of this study did not reveal statistically significant differences in the expression of adenylyl cyclase signaling system components between the withdrawal and the corresponding control groups of animals, confirming high ability of the organism to withstand morphine administration and to return to...
Sexual dimorphism of rat gut microbiota composition and intestinal immunity
Kalousová, Pavla ; Kovařík, Miroslav (advisor) ; Jílek, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Pavla Kalousová Supervisor: PharmDr. Miroslav Kovařík, Ph.D. Title: Sexual dimorphism of rat gut microbiota composition and intestinal immunity Background and Aim: Many factors can influence the composition of gut microbiota and the immune system. It is well-known that one of those factors is sex. This sexual dimorphism can lead to a specifically adjusted treatment of diseases for different gender and nutritional interventions. This study focuses on analysing sexual differences in gut microbiota and intestinal immunity in adult rats. Methods: Caecal content from 12-week-old female and male Wistar rats were collected and analysed by DNA-sequencing technique to characterize microbiota composition. ELISA test was performed to quantify the concentration of IgA in faeces and gut wash. Flow cytometry determined the concentration of IgA-coating bacteria in faecal samples. Results: Metagenomic analysis revealed that female gender presents 1 phylum, 4 families, 13 genera, and 13 species which are not present in male rats. Only one male-specific colonization was observed at the species level. Quantitative analysis showed a higher proportion of Firmicutes phylum in males which was associated with...
Analysis and Detection of RAT Malware
Sidor, Samuel ; Frolka, Jakub (referee) ; Hajný, Jan (advisor)
Goal of this bachelor’s thesis is studying problematics of various types of malware with specific focus on RAT (Remote Access Trojan) category. This thesis will also acquaint reader with static and dynamic binary analysis and terms like reverse engineering, sandboxing, decompilation, etc. Then chosen malware families will be analysed and for these families detection rules in YARA language will be created. Except this, reader will be acquainted also with protection against RAT malware and finally data acquired from detail analysis will be evaluated.
Evidence securing in virtual environment
Havlová, Miluše ; Malina, Lukáš (referee) ; Martinásek, Zdeněk (advisor)
The bachelor thesis deals with evidence securing in virtual environment. The main goal is to suggest suitable virtual environment for evidence securing which can be used in prosecution. As the next the tools that are suitable for safe securing of evidence are described. With the help of selected tools the sample of malware is secured and then the sample is analyzed and described. The suggested environment is used to evidence gathering within the frame of simulated security incident.

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