National Repository of Grey Literature 11 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
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.
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.
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.
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.
Forms of Patronage in Czech Environment
Vrbová, Kristýna ; Czumalo, Vladimír (advisor) ; Jarošová, Markéta (referee)
The author of this diploma thesis will conduct an interdisciplinary synthesis about signficance of patronage in history of Czech art. The core of the thesis will be an analysis of the chosen phenomenon through four case studies dedicated to selected personalities, who represent different eras and different forms of patronage: Josef Hlávka, Václav Špaček ze Starburgu, August Švagrovský and Pavel Vašíček. Main chapters will prepare critical evaluation of existing literature as well as general exposition of the subject of the thesis. Case studies will be genereallised and sumarized in the final chapter, which will define specifics of patronage in Czech environment. Picture attachment will be a part of the thesis. Keywords patron, patronage, Josef Hlávka, August Švagrovský, Václav Špaček ze Starburgu, Pavel Vašíček
In vitro cultivation of the trematode species Trichobilharzia regenti
Vrbová, Kristýna ; Kašný, Martin (advisor) ; Skelly, Patrick (referee)
The class Trematoda includes many pathogenic representatives. Main subject of this thesis, avian schistosome Trichobilharzia regenti, is a close relative to the important human pathogen Schistosoma mansoni (family Schistosomatidae). In vitro cultivation of trematodes enables closer understanding of their biology and parasite- host interactions; however, no trematode species has been successfully kept in vitro from the egg stage to the adults producing eggs. Many studies are focused on the problematic of S. mansoni cultivation, but data concerning T. regenti cultivation remain scarce. Only the ability of T. regenti cercariae to transform into schistosomula in vitro was documented, with following survival in a culture medium for a few days. Comparison of eight transformation methods was performed with T. regenti cercariae. Based on the number of tailless cercarial bodies obtained, five transformation methods were selected for further evaluation of the early schistosomula characteristics (glycocalyx shedding, penetration glands emptying and survival in vitro). It was observed that the largest quantity of cercarial bodies can be obtained by using a syringe needle or the BeadBeater cell disrupter. The largest quantity of schistosomula meeting the criteria of early schistosomulum was recorded after...
How Jindřich Prucha understood Antonín Slavíček
Vrbová, Kristýna ; Lahoda, Vojtěch (advisor) ; Prahl, Roman (referee)
The main goal of this Bachelor's thesis is to point out a connection between painter Jindřich Prucha and Antonín Slavíček.The thesis compares and comments several of their paintings, with same or very similar theme. These topics are : funeral, Golden Lane, village Kameničky and view into the forrest. Antonín Slavíček, famous artist belonged to the older generation of artists than Prucha did. Jindřich Prucha belonged to generation of group called Osma, nevertheless their creation remained unfamiliar for him. The main reason was propably acceptance of international themes and procedures, which Prucha fundamentally disapproved. However Prucha finds his place as a continuator of Antonín Slavíček's tradition. They both admired and loved Czech landscape and people living in it, in this aspect Prucha really fully understands Slavíček. As we find out from his correspondence, Prucha may got even further in this tradition. For his creation he needs the exact landscape, which is close to him, and which is his homeland - in his case Iron Mountains. Keywords Jindřich Prucha, Antonín Slavíček, landscape, Iron Mountains, Kameničky, funeral, Golden Lane
Cultivation of Trematodes
Vrbová, Kristýna ; Kašný, Martin (advisor) ; Chanová, Marta (referee)
Many of Trematode species are serious pathogens of human and animals; therefore they are the subjects of intensive investigation. The successful in vitro cultivation of these organisms could represent the first step for further sophisticated experiments focused on characterization of crucial biological processes related to the particular phases of fluke life cycle or for the studies focused on testing the anthelmintic effect of various compounds. This thesis reviews majority of information published in relation to in vitro cultivation of Trematodes. It shows that for many Trematode families is our knowledge of culturing methods very limited. In contrast to the first attempts to cultivate some species of Trematodes about 100 years ago, nowadays we dispose of technologies enabling to cultivate particular live cells isolated from different tissues of flukes. Some of the cultivation media originally used for cell cultures are now commercially available and they were successfully used for cultivation of whole worms. Nevertheless, we still haven't been able to continuously cultivate a Trematode species by using an egg at the beginning and finish with fully developed adult producing eggs. However, there are some partially successful experiments in which development of particular life stages of some flukes has been...
Suicidal behaviour in adolescent age
Vrbová, Kristýna ; Chudomelová, Lenka (advisor)
The present thesis aims to concentrate available sources of scientific literature on adolescent suicidal behavior, which would also provide a tutu on certain issues holistic view. In the introductory part of the thesis points to the fact that suicidal behavior is being explored especially psychiatric disciplines because in psychiatric disorders are at high risk of suicidal behavior. The seriousness of this issue and the benefit of that statistical data on both the domestic and the World Health Organization, the number of suicide attempts and suicides are mentioned also the trends per decade for the Czech Republic (from r. 1990). In the next part of the thesis are presented in various forms of suicidal behavior with an indication of the usual motivation, quantitative data on the most frequently used methods of suicide in this country and abroad. In connection with the study of adolescent suicidal behavior are also explored in parallel manifestations of self-harm, stating the characteristic differences. The analysis of risk factors for suicidal behavior in children and adolescents. Special attention is paid to the influence of the family, the school environment, the role of their own state of health, religion, social situation, etc. Separately are analyzed negative effects of drug addiction. Attention is also...
Effect of oxidative stress on antioxidant systems, telomere length and telomerase activity in \kur{Locusta migratoria}
VRBOVÁ, Kristýna
Oxidative stress is caused by an imbalance between oxidants and antioxidants. Oxidative stress generated by reactive oxygen species (ROS) or reactive nitrogen species (RNS) occurs when protection of antioxidants fails or when an amount of ROS is too high. Telomeres, regions of repetitive nucleotide sequences at the end of chromosomes, are especially sensitive to oxidative stress because they contain a lot of guanine which is often oxidised. Antioxidants play an important role in protection against oxidative stress. In this thesis I analysed the effect of oxidative stress caused by paraquat on activity of antioxidant enzymes (catalase and superoxide dismutase) and telomere length in Locusta migratoria. I also studied differences in telomere length between locusts of various development stages and telomerase activity in locusts and other Orthoptera.

National Repository of Grey Literature : 11 records found   1 - 10next  jump to record:
See also: similar author names
6 VRBOVÁ, Kateřina
8 VRBOVÁ, Kristýna
6 Vrbová, Kateřina
1 Vrbová, Klára
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