National Repository of Grey Literature 15 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Molecular mechanisms of carcinogenic effects of alcohol
Vepřková, Jana ; Kábelová, Adéla (advisor) ; Novotná, Božena (referee)
Alcohol (ethanol) enters the human body mainly through ingestion of alcoholic beverages and its chronic consumption is considered a worldwide socio-economic problem. Besides others, alcohol consumption increases the risk of development of breast, liver, colorectal and upper aerodigestive tract cancer. In the liver, ethanol is metabolised into toxic acetaldehyde which is the main cause of DNA damage leading to cancer development. Acetaldehyde covalently interacts with nucleotides in the DNA forming DNA adducts such as N2 -ethylidene-2'-deoxyguanosine or S- and R-α-methyl-γ-hydroxy-1,N2 - propano-2′-deoxyguanosine. Acetaldehyde can also interact with proteins and disrupt their function. Ethanol metabolism by cytochrome P450 2E1 leads to production of reactive oxygen species, that subsequently damage cellular molecules such as lipides and DNA. Ethanol also initiates carcinogenesis through aberant DNA methylation or interference with retinoic acid metabolism. In cancer development, alcohol interacts with other environmental and genetic factors, which can increase the risk of developing cancer in predisposed individuals.
The use of comet assay for measurement of DNA integrity in clinical and applied research
Bagryantseva, Yana ; Novotná, Božena (advisor) ; Rubeš, Jiří (referee) ; Štětina, Rudolf (referee)
Single cell gel electrophoresis or comet assay combined with enzymes of excision repair is a method for measuring DNA strand breaks and oxidative damage. Using this approach we analysed ineffective hematopoiesis in patients with low-risk MDS. Refractory anemia (RA) exhibited a higher DNA instability in bone marrow cells when compared to controls and the extent of DNA fragmentation correlated with cytopenia. No similar relationship was observed in RA with ring sideroblasts (RARS), although the levels of DNA breaks markedly exceeded even the values detected in RA. Both groups of patients also showed high levels of oxidative damage to DNA. However, there was no clear relationship to the levels of serum ferritin, cytopenia or associated inflammation. This suggested that the oxidative DNA damage per se is not responsible for extensive apoptosis in low-risk MDS. In any case, it undoubtedly contributes to genome instability and disease progression. The second part of thesis was aimed to the impact of air pollution and genetic polymorphisms on oxidative damage to DNA, lipids and proteins of city bus drivers and garagemen. Both groups exhibited a higher level of DNA breaks and oxidative damage to proteins than the controls, while an increased level of lipid peroxidation was detected only in bus drivers. The...
Embryotoxicity test of thyroxine on chick embryo.
Petrušková, Michaela ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
Thyroxine is the main thyroid gland's hormone. The state, when the thyroid gland does not produce enough of it into the bloodstream is called hypothyroidism. Hypothyroidism is related with several health complications; therefore it is required to take replacement therapy in adequate doses. Concerning pregnant women, it is important especially to keep the blood level of thyroxine in the normal, because increasing or decreasing of it, has an adverse effect on the health of the mother and also on the normal child development. The objective of my thesis was to describe malformations spectra of thyroxine, to find out the beginning of its embryotoxicity dose range for chick embryos, and recalculate this value for human embryos, allowing us to decide, if the level of thyroxine was increased by a replacement therapy, this could be embryotoxic for human. The experimental part of my work was to search an alternative method for testing embryotoxicity on chick embryos in ovo - CHEST, testing of embryotoxic potential of the thyroxine. Embryotoxicity is a feature of the external factors affecting the embryo, it may manifest as lethality, growth retardation, and teratogenicity; which is an ability of the external factor to induce the developmental defect. The most common manifestation of embryotoxicity in this...
Testing of embryotoxicity of selected human teratogenes on chicken embryos.
Pavlíková, Zuzana ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
Teratogenes are external environmental factors that can cause a developmental or a congenital defect in exposed individuals. The methods used for detecting the embryotoxic effect of substances are the classic when laboratory mammals are used and the alternative which use in vitro and in ovo systems. The main difference between these two is that the alternative methods lack metabolism of maternal organism. The metabolism of maternal organism brings a high variability of results to systems of the classic methods. We used two alternative methods in this thesis, both using chicken embryo. The first of them was in ovo method called CHEST (Jelínek, 1977). CHEST method can be used for administration of tested substances from ED2 to ED6. The disadvantage of this method is due to the dilution of the tested substance after subgerminal application at ED2. Therefore we developed in vitro method called SANDWICH. No dilution occurs while using the SANDWICH method. The aim of this study was to develop in vitro method SANDWICH while using proven teratogene (all-trans retinoic acid) and its solvent (dimethyl sulfoxide), to estimate beginning of the embryotoxicity dose range for both substances using CHEST and SANDWICH, and finally to compare obtained results. We confirmed the embryotoxic effect of all-trans...
The problem of infertility and the methods of resolving..
Semyakina, Anastasiya ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
4 Abstract This diploma thesis is concerned with modern methods of treatment for infertility. It examines to what extent and in what cases are these methods used and what risk does it pose for a woman's and a child's health. Paticular emphasis is placed on the methods of assisted reproductive technology as the most used, effective and the most invasive. Nowadays 10-15% of couples face the problem of infertility. In most of the cases this problem can be solved with the help of hormonal therapy, surgery or assisted reproductive technology. The most common complication of ART (assisted reproductive technology) is ovarian hyperstimulation syndrome which leads to higher frequency of miscarriages and can be fatal for a woman. Since more that one embryo is usually transferred in ART children conceived with the help of this method can face different problems related to multiple pregnancy such as higher risk of preterm birth, higher risk of congenital disorder or intrauterine growth retardation. Key words: ART, assisted reproductive technology, infertility, congenital disorder, multiple pregnancy
Summary of types of human limbs defects.
Hundsnurscherová, Zdeňka ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
The prenatal growth of the upper and lower human limbs is sensitive to disruption during the critical period, beginning on day 25 from conception, until day 35 for upper limbs. For the lower limbs the development begins and ends about a day or two later. This period is followed by a minor critical period, when there is no risk of a severe developmental defect, and it lasts up until the end of the week 8 from conception. At the beginning of the critical period large developmental defects can develop (amelia, phocomelia, hemimelia, ektromelia and sirenomelia), later small defects can develop, that affect mainly distal structures of the limbs (longitudinal preaxial reduction, longitudinal postaxial, longitudinal pre- and postaxial). Apart from the critical period, a sensitive period exists, a period in which cells of the developing organs are sensitive to negative effects of the external environment. External negative effects are called teratogens and they generally include factors like drugs (thalidomide, vitamin A, misoprostol, phenytoin, methotrexate). Part of the external negative effects as well, are physical ones, such as hypoxia and hyperthermia, radiation, and also biological factors such as bacterial, viral and parasitic infections. Chemical and physical external effect is the most common...
Mutagenic and Antimutagenic Effect of Environmental Substances
Langová, Martina ; Vodička, Pavel (advisor) ; Sedmíková, Markéta (referee) ; Novotná, Božena (referee)
In the present study were used reference mutagens which effects mutagenic activity in prokaryotic and eukaryotic testing systems. Aflatoxin B1 (AFB1) is one of the most thoroughly studied and the well known mycotoxin with carcinogenic activity. 2-Amino-3-methylimidazol[4,5-f] quinoline (IQ) in isolated form has been used as another reference mutagen. These compounds are indirect acting genotoxins, i.e. need metabolic activation to exert genotoxic effect. As a third reference mutagen in the present study there has been chosen N-nitroso-N-methylurea (MNU) which is direct acting carcinogenic N-nitroso compound. The aim of the study was to investigate antimutagenic effects of ellagic acide (EA), resveratrol (RES), diallyl sulfide (DAS) and phenetyl isothiocyanate (PEITC) on the mutagenicity of the mutagens. The Ames test with Salmonella typhimurium TA98 and TA100 strains was used for the evaluation of antimutagenic effect of EA, RES, DAS and PEITC in vitro.
Znečištění ovzduší a ochrana zdraví
Zdravotní ústav se sídlem, Praha ; Zdravotní ústav se sídlem v Kolíně ; Ústav experimentální medicíny AV ČR, Praha ; Dostál, Miroslav ; Suchánková, Zuzana ; Beneš, Ivan ; Novák, Jiří ; Solanský, Ivo ; Sevastyanova, Oksana ; Milcová, Alena ; Stávková, Zdena ; Dušek, Zdík ; Chvátalová, Irena ; Beskid, Olena ; Novotná, Božena ; Šmerhovský, Zdeněk ; Binková, Blanka ; Šrám, Radim J.
Cílem projektu je stanovit rizika expozice nízkým hladinám komplexních směsí látek přítomných ve znečištěném ovzduší, hodnocení dlouhodobých účinků znečištění v Praze a v Teplicích. Vyhodnotit následky kombinovaného působení biologicky aktivních látek ve vztahu ke genotypu a se zřetelem k životnímu stylu validovat biomarkery zátěže lidské populace polutanty z ovzduší. Odhadnout podíl hlavních zdrojů na této zátěži a vypracovat systém interpretace získávaných dat. Projekt bude metodicky navazovat na Program Teplice I a II a "Program znečištění ovzduší a zdraví". Pro zajištění cíle byly řešeny 3 projekty: Projekt 1 Hodnocení projevů genotoxicity ovzduší u environmentálně exponovaných osob, Projekt 2 Dopady znečištění ovzduší na výsledky těhotenství, Projekt 3 Studium mechanismů působení komplexních směsí organických látek z ovzduší v buněčných systémech in vitro. Přehled o řešení jednotlivých podprojektů v roce 2003.

National Repository of Grey Literature : 15 records found   1 - 10next  jump to record:
See also: similar author names
20 NOVOTNÁ, Barbora
6 NOVOTNÁ, Blanka
20 Novotná, Barbora
6 Novotná, Blanka
2 Novotná, Bára
Interested in being notified about new results for this query?
Subscribe to the RSS feed.