National Repository of Grey Literature 22 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Post-Translational Modifications of Nuclear and Non-Nuclear Proteins in Spermatozoa
Řimnáčová, Hedvika ; Nevoral, Jan (advisor) ; Krapf, Dario (referee) ; Álvarez Rodríguez, Manuel (referee)
Posttranslational modifications of nuclear and nonnuclear proteins in spermatozoa Summary The number of couples who need the help of assisted reproductive technology (ART) has increased over the years. Approximately half of the cases are caused by male infertility, which is often diagnosed as idiopathic infertility. Therefore, the search for male fertility markers will improve male infertility diagnosis, thereby facilitating advanced sperm treatment and selection via ART. Posttranslational modifications (PTMs) of sperm nuclear and nonnuclear proteins are suitable candidates for such markers. The PTMs of protamines and histones reflect sperm chromatin maturity and its readiness for fertilization, and accordingly, they can predict the outcome of ART. However, the PTMs of nonnuclear proteins, including cytoplasmic, cytoskeletal, and membrane proteins, reflect the ability of sperm to undergo hyperactivation, capacitation, or acrosome reactions, which are processes essential for fertilization. We hypothesize that the PTMs of nuclear and nonnuclear proteins can reflect sperm quality and, thus, serve as a valuable marker in ART. Additionally, we suggest that the in vitro addition of hydrogen sulfide into the sperm-manipulating media improves sperm motility and viability via persulfidation. We used Western blot...
The influence of selected environmental pollutants on gametogenesis and early embryonic development
Fenclová, Tereza ; Nevoral, Jan (advisor) ; Děd, Lukáš (referee) ; Sovadinová, Iva (referee)
The influence of selected environmental pollutants on gametogenesis and early embryonic development Ing. Tereza Fenclová Idiopatic infertility is a serious problem, which can be caused by exposure to endocrine disruptors, e.g. bisphenols. Bisphenol A, the most widely used bisphenol, is now being replaced in manufacturing processes due to its toxicity by its analogues, bisphenol S and F. While most of the scientific experiments examine the effect of toxic doses after direct exposure, this study provides results for exposure to real low doses after direct and indirect exposure. We assumed a negative effect of direct and indirect exposure to low doses of alternative bisphenols BPS and BPF on male and female reproduction at the level of gametes and embryos. The aim of this work is to evaluate the effect of direct exposure to mouse oocytes and sperm, to evaluate the effect of indirect exposure through breast milk to mouse oocytes, sperm, testicular tissue and the extent of damage to early embryonic development. Experimental ICR laboratory mice were exposed to low doses of bisphenols directly via drinking water or an oral gavage, or indirectly through the breast milk. Direct exposure to low doses of bisphenols affects the reproductive abilities of females mainly by malformations of the dividing spindle of...
NAD+-dependent histone deacetylase SIRT1 in the process of oogenesis, fertilization and early embryonic development
Valentová, Iveta ; Nevoral, Jan (advisor) ; Drutovič, David (referee)
SIRT1 is a histone deacetylase from the sirtuin family that affects epigenetic and non- epigenetic targets. We can assume that the known SIRT1 substrates are involved in the regulation of gametogenesis and early embryonic development. Our hypotheses say SIRT1 is present in oocytes and early embryos and it plays a physiological role in oocyte maturation, fertilization and early embryonic development. A mouse model of a conditional knock-out line producing Sirt1-deficient oocytes was developed to verify our hypotheses. Oocytes and embryos were analyzed for SIRT1, its selected substrates and other markers by immunocytochemistry. We found out that the presence of SIRT1 contributes to oocyte quality through modulation of the chromatin histone code and stabilization of the spindle. Furthermore, the purely maternal origin of SIRT1 presents in both zygote pronuclei. Last but not least we discovered a significant effect of SIRT1 on early embryonic development, probably mainly due to its role in the activation of the embryonic genome. The results confirm our hypothesis that SIRT1 is present in oocytes and embryos mainly around chromatin. The results show that SIRT1 is a maternal factor determining oocyte quality and it is necessary for the embryonic genome activation.
The Role of Cellular Metabolism in Carcinogenesis. Molecular Pathophysiology of Bladder Cancer Chemoresistance
Kripnerová, Michaela ; Kuncová, Jitka (advisor) ; Nevoral, Jan (referee) ; Chovanec, Miroslav (referee)
Therapeutic resistance of tumours represents an important clinical issue. We can classify the therapeutic tumour resistance in two ways. According to the clinical course, tumours can behave either as primary resistant, i.e. from the very beginning not responsive, or they can display a secondary (also called acquired) resistance, whereby an initial clinical response is lost and the tumour develops into chemo-, radio- or immunoresistant disease. An alternative classification distinguishes cell autonomous resistance mechanisms from resistance that relies on complex interactions within the context of tumour microenvironment. From the research perspective, modelling therapeutic resistance frequently involves experimental treatment of sensitive cancer cells and selection of daughter resistant cell lines. The Ph.D. thesis includes derivation of two unique models of urothelial bladder carcinoma therapeutic resistance. The first model involves newly established urothelial carcinoma cell lines BC44 and BC44DoxoR, which resulted from a prolonged doxorubicin exposure of the mother cell line. The daughter chemoresistant cell line exhibits multidrug resistant phenotype, which extends beyond the selecting drug - doxorubicin - to four additional chemotherapeutic drugs (cisplatin, methotrexate, vinblastine, and...
Age-related differences in translation of mammalian oocytes
del Llano Solanas, Edgar ; Kubelka, Michal (advisor) ; Nevoral, Jan (referee) ; Valášek, Leoš (referee)
Female germ cells (also known as oocytes) from mammalian species are found in the ovaries in a state of meiotic arrest at prophase I. It is not until puberty that oocytes start to be selected to grow, overcome their meiotic arrest and ovulate, so they become capable of being fertilized and give rise to new individuals. Half of the genetic information from these new individuals comes directly from the oocyte itself, therefore, oocyte and meiosis quality are of great importance for the reproduction. One of the factors, which can drastically reduce oocyte quality in several mammalian species is the advanced age of females. In both mice and humans age-related poor oocyte quality is reflected by a large increase of chromosomal aneuploidy rates. Having an incorrect number of chromosomes reduces embryo viability and may cause severe clinical outcomes. The work of this thesis was primarily directed towards a better understanding of the causes behind age-related aneuploidy in mice oocytes. One of the most characteristic features of oocytes is the fact that they become transcriptionally silent after meiotic resumption, relying heavily on translational control for protein expression. Here we show that after nuclear envelope break down (NEBD), one of the main protein kinases regulating translational...
Novel approach to polymorphism in gate-level digital circuits
Nevoral, Jan ; Plíva, Zdeněk (referee) ; Stopjaková,, Viera (referee) ; Růžička, Richard (advisor)
Před necelými dvaceti lety byl představen nekonvenční přístup k implementaci multifunkčních obvodů, tzv. polymorfní elektronika. Polymorfní elektronika umožňuje implementovat jedním obvodem dvě nebo více funkcí, přičemž aktuálně funkce závisí na stavu okolního prostředí obvodu. Klíčovými komponentami takových obvodů jsou polymorfní hradla. Od představení konceptu polymorfní elektroniky bylo publikováno několik desítek polymorfních hradel. Parametry většiny z nich však neumožňují jejich využití v reálných aplikacích. Bez dostatečného množství polymorfních hradel s dobrými parametry však nejspíše zůstane v aplikacích založených na multifunkčním chování nebo rekonfiguraci konvenční elektronika preferována před tou polymorfní. Tato disertační práce představuje nový přístup k polymorfní elektronice. Je založen na hradlech, jejichž funkce závisí na polaritě napájecích přívodů. Cílem této disertační práce je ukázat, že takový přístup umožňuje navrhnout hradla s výrazně lepšími parametry. Aby bylo možné systematicky navrhovat na úrovni tranzistorů takováto hradla, byla navržena evoluční metoda založená na kartézském genetickém programování (CGP). To umožnilo navrhnout několik sad efektivních polymorfních hradel založených jak na konvenčních MOSFET tranzistorech, tak na double-gate ambipolárních tranzistorech. Z těchto sad hradel byla vytvořena knihovna, která je v současné době volně dostupná pro ostatní vědce. Dále byla v této práci navržena řada složitějších obvodů založená na navržených hradlech. Na různých úrovních návrhu obvodů (hradla, RTL, cílová aplikace) je pak ukázáno, že navrhovaný polymorfismus na úrovni hradel představuje velké výhody v porovnání s předchozí generací polymorfních hradel, ale může být také konkurenceschopný nebo výrazně lepší než konvenční řešení takovýchto obvodů.
Laser Plotter for Cutting Steel Plates
Dokulil, Marek ; Nevoral, Jan (referee) ; Crha, Adam (advisor)
This diploma thesis is divided into two main parts. The first section is dedicated to the history and development of the laser technology. The second part describes all individual types of laser technology which are used in the industry nowadays. The next section follows with the research of various laser devices which serve mainly as a cutting tool. This knowledge gathered in the previous part was used to create the next part including the own conception of the machine. The second half of this diploma thesis deals with a research of software available at the market today. Eventually, after summarizing the characteristics of each software, the new concept and implementation of own software are made. In the final section, there are mentioned the possible extension and available upgrades. The reader should be able to create his/her own conception of the laser device and software after reading and understanding this paper.
Digital Steganalysis
Molnár, Ondřej ; Nevoral, Jan (referee) ; Strnadel, Josef (advisor)
Steganalysis is the opposite science discipline of the steganography - which is an art of information hiding . Steganography deals with embedding of secret messages to different types of media. The most commonly used cover media in modern steganography are image files . This bachelor's thesis creates an overview of known steganograpy and steganalysis methods . It also describes practical implementation of application that is able to detect hidden information in image.
Epignetic Modifications of the Sperm and the Application in Clinical Practice of Human Assisted Reproduction Therapy
Štiavnická, Miriama ; Nevoral, Jan (advisor) ; Kloudová, Soňa (referee) ; Vašíček, Jaromír (referee)
Basement of healthy embryo development comes from quality of oocytes and spermatozoa. Today, when percentage of couples suffering infertility together with assisted reproductive therapy (ART) is increasing, understanding to gamete biology and heritable epigenetic code is crucial. The study is focused on promising epigenome based markers that could serve as indicators of gamete quality for either their screening or selection for ART. Accordingly selected markers were used for the investigation of environmental pollutant bisphenol S (BPS) effect on gametes quality. To obtain these aims, we have used human semen samples, boar semen samples and ICR mice gametes. Samples were analyzed by flow cytometry, immunocytochemistry and western blot analysis. All experimental work was in accordance with Ethics committee University Hospital in Pilsen and approved experimental designs for appropriate experimental animal project. In the study, we detected the dimethylation of histone H3 on lysine K4 (H3K4me2) as potential epigenetic marker of sperm quality and chromatin immaturity. Secondly, we observed the role of the gasotransmitter hydrogen sulphide (H2S) as anti-capacitating agents, slowing down capacitation possibly through post-translational modification of proteins. Thirdly, SIRT1 histone deacetylase was...
The Role of Cellular Metabolism in Carcinogenesis. Molecular Pathophysiology of Bladder Cancer Chemoresistance
Kripnerová, Michaela ; Kuncová, Jitka (advisor) ; Nevoral, Jan (referee) ; Chovanec, Miroslav (referee)
Therapeutic resistance of tumours represents an important clinical issue. We can classify the therapeutic tumour resistance in two ways. According to the clinical course, tumours can behave either as primary resistant, i.e. from the very beginning not responsive, or they can display a secondary (also called acquired) resistance, whereby an initial clinical response is lost and the tumour develops into chemo-, radio- or immunoresistant disease. An alternative classification distinguishes cell autonomous resistance mechanisms from resistance that relies on complex interactions within the context of tumour microenvironment. From the research perspective, modelling therapeutic resistance frequently involves experimental treatment of sensitive cancer cells and selection of daughter resistant cell lines. The Ph.D. thesis includes derivation of two unique models of urothelial bladder carcinoma therapeutic resistance. The first model involves newly established urothelial carcinoma cell lines BC44 and BC44DoxoR, which resulted from a prolonged doxorubicin exposure of the mother cell line. The daughter chemoresistant cell line exhibits multidrug resistant phenotype, which extends beyond the selecting drug - doxorubicin - to four additional chemotherapeutic drugs (cisplatin, methotrexate, vinblastine, and...

National Repository of Grey Literature : 22 records found   1 - 10nextend  jump to record:
See also: similar author names
10 Nevoral, Jiří
1 Nevoral, Josef
Interested in being notified about new results for this query?
Subscribe to the RSS feed.