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SIZE AS AN IMPORTANT FACTOR IN NANO-TiO2 TOXICITY IN MACROPHAGE-LIKE CELLS
Líbalová, Helena ; Sikorová, Jitka ; Brzicová, Táňa ; Milcová, Alena ; Vrbová, Kristýna ; Pikal, P. ; Topinka, Jan ; Rössner ml., Pavel
A set of NPs consists of 5 variants of anatase and 5 variants of rutile nanoparticles differing in their diameter (from 3 to 165 nm). TiO2 samples were characterized in the powder form and dispersed in water and cell culture media. Three cytotoxicity assays were used: MTS, WST-1, and LDH. For all nanomaterials, three independent repetitions were carried out. \n\nOverall, cytotoxicity of all NPs was low even at the highest concentration of 256 mu g/ml. The viability of cells did not decrease below 60% for WST-1 and MTS assays and 80% for the LDH assay. Besides concentration, crystalline size was identified as the most important cytotoxic factor. Clear nonlinear relationship between crystalline size and cytotoxicity was detected, higher toxicity induced NPs within the size range 20-60 nm. Increased cytotoxicity in given diameter size range would give an answer to inconsistent findings at size and cytotoxicity relationship.
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GENOTOXICITY OF NANOMATERIALS IN BEAS-2B CELLS ANALYZED BY THE IN VITRO MICRONUCLEUS ASSAY
Rössnerová, Andrea ; Červená, Tereza ; Brzicová, Táňa ; Vrbová, Kristýna ; Sikorová, Jitka ; Topinka, Jan ; Rössner ml., Pavel
The tremendous increase of the use of nanomaterials (NMs) has been witnessed during the last decade in many areas of human life including the chemical industry, cosmetics, biomedicine or food technology. The variety of NMs, their unique properties, almost ubiquitous presence and the size range of 1-100 nm raised the interest of toxicologists. The evaluation of the frequency of micronuclei (MN) as a result of the genotoxic events is a broadly utilized and well-established approach in in vitro studies for testing the risk of chemical exposure. Nevertheless, properties of the NMs give rise to the questions concerning the optimal methodological variants of the MN assay. \n\nIn our study, five types of well-characterized NMs (TiO2: NM-101 and NM-103, SiO2: NM-200, Ag: NM-300K and NM-302) of specific size, shape, or e.g. dimensions of aggregates were involved in the genotoxicity testing using four variants of protocols differing in the time of NM exposure, application of cytochalasin-B combined with simultaneous and delayed co-treatment with nanoparticles (NPs). Bronchial epithelial cells (BEAS-2B) were used in this study to fulfil these tasks. Presence of NPs was controlled by transmission electron microscopy (TEM). \n\nObtained results showed the different genotoxic potential of the various TiO2 and Ag NMs (NM-101< NM-103 and NM-300K> NM-302, respectively). Comparison of all testing strategies revealed, that the level of DNA damage can differ based on the time of exposure and the methodological approach. In general, using cytochalasin-B led most frequently to the increase of the genotoxic potential of the tested NMs.
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WHOLE-GENOME EXPRESSION ANALYSIS IN THP-1 MACROPHAGE-LIKE CELLS EXPOSED TO DIVERSE NANOMATERIALS
Brzicová, Táňa ; Líbalová, Helena ; Vrbová, Kristýna ; Sikorová, Jitka ; Philimonenko, Vlada ; Kléma, J. ; Topinka, Jan ; Rössner ml., Pavel
From the perspective of the immune system, nanomaterials (NMs) represent invading agents. Macrophages are immune cells residing in all organs and tissues as the first line of defense. Interactions of macrophages with NMs can determine the fate of NMs as well as their potential toxic effects. In the present study, we compared toxicity of four different types of NMs [NM-100 (TiO2, 110 nm), NM-110 (ZnO, 20 nm), NM-200 (SiO2, 150 nm) and NM-300K (Ag, 20 nm)], towards THP-1 macrophage-like cells. Cells were incubated with non-cytotoxic concentrations (1-25 mu g/ml) of NMs for 24 hours and microarray technology was used to analyze changes in whole-genome expression. Gene expression profiling revealed a substantially different molecular response following exposure to diverse NMs. While NM-100 did not exert any significant effect on gene expression profile, all other NMs triggered a pro-inflammatory response characterized by an activation of the NF-kappa B transcription factor and induced expression of numerous chemokines and cytokines. NM-110 and NM-300K further modulated processes such as DNA damage response, oxidative and replication stress as well as cell cycle progression and proteasome function. We suppose that genotoxicity of ZnO and Ag NMs leading to DNA damage and alternatively to apoptosis in THP-1 macrophages is probably caused by the extensive intracellular dissolution of these NPs, as confirmed by TEM imaging.
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GENE EXPRESSION AND IMMUNOLOGICAL RESPONSE IN MICE EXPOSED TO ZnO NANOPARTICLES
Rössner ml., Pavel ; Vrbová, Kristýna ; Strapáčová, S. ; Rössnerová, Andrea ; Ambrož, Antonín ; Brzicová, Táňa ; Líbalová, Helena ; Javorková, Eliška ; Zajícová, Alena ; Holáň, Vladimír ; Kulich, P. ; Večeřa, Zbyněk ; Mikuška, Pavel ; Coufalík, Pavel ; Křůmal, Kamil ; Čapka, Lukáš ; Dočekal, Bohumil ; Šerý, Omar ; Machala, M. ; Topinka, Jan
We analyzed gene expression changes in the lungs and the immunological response in splenocytes of mice exposed by inhalation of ZnO nanoparticles - NP. Adult female ICR mice were treated for three days and three months, respectively. Analysis of differential expression in genes involved in oxidative stress was conducted using quantitative RT-PCR. The potential immunotoxic and immunomodulatory effects of ZnO NP were analyzed by phenotyping and cytokine production by splenocytes after three months exposure. Three days exposure resulted in down-regulation of GCLC, GSR, HMOX-1, NQO-1, NF-kB2, PTGS2 and TXNRD1 mRNA expression, three months exposure increased the expression of these genes. Three months exposure caused a significant decrease in the percentage of granulocytes in the spleen cells, and affected the production of IL-10 and IL-6 by lipopolysaccharide-stimulated leukocytes. In summary, our study revealed changes in the expression of genes involved in the oxidative stress response following acute ZnO NP exposure. Subchronic ZnO NP exposure induced immunomodulatory effects in the spleen.
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Use of transcriptomics to study mechanism of the action of complex mixtures of organic compounds occurring in the ambient air focusing on polycyclic aromatic hydrocarbons
Líbalová, Helena ; Topinka, Jan (advisor) ; Krásný, Libor (referee) ; Postlerová, Pavla (referee)
Polycyclic aromatic hydrocarbons (PAH) represent a large group of organic compounds occuring as pollutants in ambient air. Besides their genotoxic effect, some of them are known to be complete carcinogens and act via nongenotoxic and tumor promoting mechanism. Although effects of many individual compounds are well-documented, human exposure to polycyclic aromatic hydrocarbons in ambient air occurs through complex mixtures and only few studies describe the behavior of PAH in real complex mixtures. The first part of the thesis is dealing with the global gene expression changes in human embryonic lung fibroblasts (HEL) as a consequence of the effect of complex mixtures containing PAH extracted from the respirable airborne particles PM2.5. These particles were collected in 4 localities in the Czech republic (Ostrava - Bartovice, Ostrava - Poruba, Karviná, Třeboň) differing in the level of the air pollution. Gene expression changes induced by three subtoxic concentrations of organic extracts (EOM - extractable organic matter) from each locality after 24 hour incubation were examined by microarray analysis. Pathway analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database was applied to interpret gene expression data. In each locality we identified several deregulated signaling pathways...
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Protection of personal rights in theatre practice
Topinka, Jan ; SRSTKA, Jiří (advisor) ; CHLOUPEK, Vojtěch (referee)
In this thesis I have described historical development of the right to the
protection of personal rights from their establishment up to the present
legal regulations. I paid great attention to description of particular
elements of the personal rights both in the area of general rights and
special ones. Those elements of personal rights are the ones I often
encounter in the frame of artistic production. I tried to interpret basic
principles and rules related to the elements of personal rights. Today, we
can see many cases in public life directly affected by these issues, so I
consider this topic to be a very hot issue. This thesis aims at making this
area of legal aspects related to conducting theatre activities more
transparent to a wider population of theatre managers.
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Vliv variability genomu na interakci lidského organismu a životního prostředí - ENVIRONGENOM
Ústav experimentální medicíny AV ČR, v.v.i., Praha ; Skorkovský, Jiří ; Benešová, Marie ; Novák, Jiří ; Tabashidze, Nana ; Švecová, Vlasta ; Špátová, Milada ; Solanský, Ivo ; Nováková, Zuzana ; Milcová, Alena ; Líbalová, Helena ; Dejmková, Eva ; Schmutzerová, Jana ; Topinka, Jan ; Rössner, Pavel ; Dostál, Miroslav ; Brdička, Radim ; Šrám, Radim
Zpráva obsahuje jednotlivé výstupy spojené s realizací projektu (články, přednášky). Je uvedeno zhodnocení znečistění ovzduší v Teplicích, Prachaticích a v Praze za období 1994-2009 a vyhodnocení vztahu mezi znečištěným ovzduším a nemocností předškolních dětí v okrese Teplice a Prachatice. Je připojena zpráva o zdravotním stavu Romů ve sledované oblasti.
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Znečištění ovzduší a ochrana zdraví
Zdravotní ústav se sídlem, Praha ; Zdravotní ústav se sídlem v Kolíně ; Ústav experimentální medicíny AV ČR, Praha ; Suchánková, Zuzana ; Solanský, Ivo ; Sevastyanova, Oksana ; Milcová, Alena ; Stávková, Zdena ; Dušek, Zdík ; Beskid, Olena ; Rössner, Pavel ; Chvátalová, Irena ; Novotná, Božena ; Topinka, Jan ; 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.
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Environmentální vlivy na zdraví dětí
Univerzita Karlova v Praze, Centrum pro otázky životního prostředí ; Ústav experimentální medicíny AV ČR, Praha ; Milcová, Alena ; Chvátalová, Irena ; Topinka, Jan ; Máca, Vojtěch ; Ščasný, Milan ; Melichar, Jan ; Braun kohlová, Markéta ; Novák, Jiří ; Nožička, Jiří ; Krejsová, Jana ; Skorkovský, Jiří ; Beneš, Ivan ; Šrám, Radim ; Solanský, Ivo ; Dostál, Miroslav
Cílem řešení tématu bylo stanovit riziko dlouhodobých účinků a změn v úrovni znečištění ovzduší na zdravotní stav dětí s použitím modelových souborů dětí z okresů Teplice a Prachatice. Pro zajištění cíle tohoto tématu byly řešeny 4 projekty: Znečištění ovzduší a nemocnost dětí, Geneticky podmíněné faktory individuální vnímavosti ke znečištěnému ovzduší a nemocnost dětí, Percepce zdravotních rizik, ochota platit za snížení rizika onemocnění dětí v oblastech se znečištěným životním prostředím, Hodnocení celkových nákladů poškození zdraví. Zpráva obsahuje popis výsledků jednotlivých projektů.
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