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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Změny fytocenóz v pahorkatinných lesích v závislosti na aplikaci historických forem obhospodařování / Changes of vegetation composition in hilly country forests depending on the application of historical forms of management

Nechanská, Denisa January 2013 (has links)
The aim of my study is to determine the influence of historical management practices on the camposition of vascular species in hilly country forests on the Vysoká stráň hill in the Bohemian Karst Protected Landscape Area in the Czech Republic. My thesis is divided into two parts. The first part of my thesis describes influences of forest management on the herb diversity from different scientific studies. There is some information about the influence of herbivorous grazing, pollarding, litter raking and fire. Secondly provides a case study dealing with the influence of historical management on the vascular species composition in the forest understory. My experimental area was divided into 32 treatments, where three different ways of historical management were used - mowing of the understory vegetation, litter raking and the combination of mowing and litter raking. The fourth area was a control treatment. Change in the herb diversity depending on a time is statistically significant but changes in the herb diversity depending on different ways of historical management are statistically insignificant. We detected a distinct decline in the herb diversity during our experiment, also on the control treatments. The main gradient of vegetation points from mesophilous acidophytes to species characteristic...
162

Krasová polje východní Hercegoviny z perspektivy ryby rodu Telestes / Telestes perspective on the karstic poljes of eastern Herzegovina

Doulíková, Tereza January 2019 (has links)
The Dinaric karst region in the Balkans is one of the hot spots of biodiversity with a high number of endemic freshwater fish. The major cause of the high degree of endemism are numerous paleoclimatic and geological events that have affected the formation of the entire area. Flows of karst poljes represent a specific ecosystem to which some fishes have adapted. The poljes have been periodically flooded and these floods may activate different underground channels, which lead to interconnection of poljes. These fish species spend a part of the year in surface water and a part in groundwater and they may use the underground flows between poljes for migration. The aim of this thesis is to evaluate the genetic variability of two endemic fish species of the genus Telestes living in karst poljes in the region of eastern Herzegovina, and to detect a possible current gene flow between populations of these species due to the connection of underground flows. For this purpose, the DNA from 102 individuals from five different localities was isolated. The mitochondrial marker cytochrom b and 16 microsatellite loci were used for the analyses. The results point to very low variability between species and populations. Based on mitochondrial marker analysis, no link between populations of the species was detected,...
163

Plži, stromy, pH, podloží a epifytické lišejníky / Gastropods, trees, pH, subsoil and epiphytic lichens

Pelant, Filip January 2020 (has links)
Epiphytic lichens are under considerable grazing pressure due to invertebrate lichenivores, mostly gastropods. Preferences of tree-climbing gastropods affect vertical distribution of lichens, their habitat preferences and whole area of distribution. Higher grazing pressure is expected on sites with basic subsoil and sufficient sources of calcium, where the abundance of gastropods is higher. Most of researches about the topic of grazing pressure were therefore conducted on such sites, although this hypothesis has never been formally tested. Epiphytic communities are also affected by pH and other properties specific to its photophyte. Nevertheless, it is not known, if the same applies for grazing gastropods and how is the grazing pressure affected by tree species. I have addressed these questions in my thesis. I set an 80-days-long field transplantation experiment in the mixed forest of Moravský kras (South Moravia, Czech Republic). Glass fiber meshes with lichen thalli were placed on sixty trunks of three tree species (Carpinus betulus - hornbeam, Abies alba - fir, Fagus sylvatica - common beech) on both calcareous (limestone) and acidic (granodiorite) sites. Abundance and diversity of gastropods were measured. Determined grazing pressure was higher than pressure detected by other authors and was...
164

Úloha imunitního systému u kolorektálního a ovariálního karcinomu / The role of the immune system in colorectal and ovarian cancer

Kocián, Petr January 2013 (has links)
Prediction of clinical outcome in cancer is usually achieved by histopathological evaluation of tissue samples obtained during surgical resection of the primary tumor. Traditional tumor staging (AJCC/UICC-TNM classification) summarizes data on tumor burden (T), presence of cancer cells in draining and regional lymph nodes (N) and evidence for metastases (M). However, it is now recognized that clinical outcome cansignificantly vary among patients within the same stage. Data collected from largecohorts of human cancers has demonstrated the impact of immune-classification, which has a prognostic value that may add largely to the significance of the AJCC/UICC TNM-classification. In our study we examined the immune cells that infiltrated the tumor tissues of colorectal and ovarian cancer patients. In a cohort of newly diagnosed colorectal cancer patients we examined the correlations between the KRAS mutational status, patterns of tumor-infiltrating immune cells and the presence of tumor recurrence. Our data suggest that colorectal cancer patients with low levels of tumor-infiltrating lymphocytes, a high CD1a/DC-LAMP tumor-infiltrating dendritic cells ratio, and a KRAS mutation in codon 13 are at a high risk of disease recurrence. In ovarian cancer patients we focused on the dynamics of the tumor-infiltrating...
165

Regulation of ERK3 by KRAS signalling and its role in the growth of lung adenocarcinoma (LUAD) cells

Akunapuram, Shreya 09 August 2023 (has links)
No description available.
166

Molekulární testování nádorů hlavy a krku asociovaných s HPV infekcí / Molecular analysis of head and neck carcinomas associated with HPV infection

Glendová, Kristýna January 2018 (has links)
Head and neck cancers (HNSCC) are highly heterogeneous disease, results from two major carcinogens - tobacco and/or alcohol, or HR HPV infection. This thesis was based on 60 biopsies of head and neck tumours embedded into paraffin after histological verification. HPV infection, including particular types was monitored in different HNSCC regions by multiplex qPCR. Subsequent IHC demonstrated expression of p16INK4A and p53 as a possible diagnostic biomarker. Based on the information, patients with HNSCC can benefit from antiEGFR therapy by Cetuximab, but so far without defined predictors, the analysis of point mutations of Ras gene family (Kras, Nras) and Braf gene was performed. These mutations were monitored as potential predictive biomarkers, in correlation with gender, age and other risk factors. For all statistical processing the Chi-x2 test was used. Key words: Head and neck cancers, biopsy, HPV types, PCR, p16INK4A, p53, molecular predictors, Kras, Nras, Braf
167

Město místo továrny - polyfunkční městský blok na Starém Brně / The city instead of the factory - multifunctional city block in the area of the Old Brno

Valová, Eva January 2010 (has links)
This thesis wants to save character and identity of local. So it offers comfortable and special living and brings new values for the local inhabitants. Integrate suitable functions to improve the quality of quater.
168

Cell type-dependent differential activation of ERK by oncogenic KRAS or BRAF in the mouse intestinal epithelium

Brandt, Raphael 10 March 2023 (has links)
Kolorektale Karzinome (CRC) zeigen eine heterogene Ätiologie. Die Progression prämaligner Vorläufer zu CRC unterscheidet (U) sich in Morphologie, molekularen Veränderungen und Interaktion mit der Tumorumgebung. CRC weisen oft onkogene Mutationen in KRAS und BRAF auf. Diese steigern die MAPK Signalwegaktivität (Mpa). Obwohl sie im selben Signalweg wirken, sind KRAS und BRAF auf die CRC-Entitäten U verteilt. Dabei ist KRAS häufiger im sogenannten konventionellen und BRAF im serratierten Weg zu CRC mutiert. In dieser Studie nutzte ich murine intestinale Organoide (iO), die induzierbare (Ind) KRAS oder BRAF Onkogene exprimieren. Große U zwischen KRAS und BRAF zeigten sich sowohl in Signaltransduktion (ST) als auch im Phänotyp. Phosphoprotein-, ERK-Reporter-, scRNA-Seq und EM-Analysen ergaben eine starke Mpa durch BRAF, die zu hoher Expression von MAPK-Zielgenen und Verlust der epithelialen Integrität führte. iO nach KRAS-Ind blieben intakt, korrelierend mit moderater, zelltypspezifischer (ZS) Mpa in sekretorischen und undifferenzierten Zellen. Die meisten Enterozyten waren Mpa-negativ. ERK-Reporter zeigten: Das ZS Muster der Mpa ist nicht nur gegenüber KRAS, sondern auch dem Entzug von Wachstumsfaktoren stabil. Dies spricht für eine intrinsische, robuste Regulierung der Mpa. BRAF-Ind Mpa setzte die ZS Regulierung der MAPK außer Kraft und schädigte das Gewebe, im Einklang mit einer oberen Grenze tolerabler Mpa. Die ZS Mpa wurde in CRC-Zelllinien bestätigt, deren Mpa durch KRAS aber nicht BRAF U ausfiel. Ferner, nutzte ich iO mit bCatenin+KRAS-Ind, um den konventionellen Weg zu CRC zu modellieren. Die Kombination führte zu synergistischen Effekten, die sich in EGFR-unabhängigem Wachstum und der Aufhebung der ZS Mpa-Blockade äußerten, die durch eine Verschiebung der Differenzierung zu mehr Progenitorzellen bewirkt wurde. Zusammenfassend konnte ich U in der Mpa durch KRAS oder BRAF im Darmepithel feststellen, was dazu beiträgt, deren Rollen in der CRC-Genese zu bestimmen. / Colorectal cancer (CRC) is a disease with heterogeneous etiology. Premalignant lesions follow distinct routes of progression to carcinoma reflected by differences in morphology, molecular alterations and the tumor environment. Mutant KRAS and BRAF are frequent, leading to MAPK pathway activation (Mpa), which is relevant for CRC therapy. Despite acting in the same pathway, mutant KRAS and BRAF segregate to different entities, as KRAS is more frequent in the conventional- and BRAF being specific for the serrated route to CRC. I used murine intestinal organoids (iO) expressing inducible oncogenic KRAS or BRAF to study the impact of oncogenes in primary cells. I found marked differences in signal transduction and phenotype. Phospho-protein, ERK-reporter, scRNA-seq and EM data showed strong Mpa upon BRAF induction followed by ERK-target gene expression leading to tissue disruption. In contrast, KRAS left the tissue intact resulting in less and cell type-dependent Mpa limited to secretory cells, a subset of late-stage enterocytes and undifferentiated crypt cells. Most enterocytes were irresponsive to KRAS. The pattern of Mpa was robust towards KRAS or growth factor depletion arguing in favor of intrinsic, resilient MAPK regulation. In iO, BRAF-induced Mpa could break this cell type-specific regulation, indicating an upper limit of tolerable Mpa. I validated these findings in CRC cell lines that differed in Mpa in response to oncogenic KRAS but not BRAF. Finally, I used iO expressing an inducible form of stabilized bCatenin in combination with KRAS to mimic events frequently found in the conventional pathway to CRC. Expression of KRAS and bCatenin synergized in driving EGFR independent growth and breaking the villus-specific block of Mpa by altering differentiation towards progenitor cell types. In summary, this study emphasizes differences between Mpa induced by oncogenic KRAS or BRAF which helps clarifying their nature in different etiological routes to CRC genesis.
169

Influence des caractéristiques morphologiques et mutationnelles des carcinomes pulmonaires sur leur environnement immunitaire et leur pronostic / Impact of mutational and morphological characteristics of non small cell lung carcinoma on immune environment and prognosis

Mansuet-Lupo, Audrey 04 July 2014 (has links)
Il est maintenant bien établi que le système immunitaire joue un rôle majeur dans le contrôle des tumeurs, y compris dans les carcinomes pulmonaires. Cependant, les interactions entre les cellules tumorales et les cellules immunitaires du microenvironnement tumoral sont mal connues. Dans ce travail, nous avons étudié les caractéristiques morphologiques et moléculaires des cellules tumorales provenant d’adénocarcinomes pulmonaires et leur association avec la composition du microenvironnement immunitaire. Nous avons rapporté la valeur pronostique des paramètres morphologiques de ces tumeurs, comme le grade histologique des adénocarcinomes, et leur association avec le statut moléculaire EGFR et KRAS. Nous avons émis l’hypothèse que la diversité morphologique et moléculaire de ces tumeurs pouvait être associée à une signature immunitaire intra-tumorale spécifique et que cela pourrait avoir un impact pronostique. Nous avons mis en évidence que la densité des cellules dendritiques matures, situées au sein de structures lymphoïdes tertiaires, variait en fonction du statut moléculaire EGFR et KRAS des tumeurs. De même, l’impact pronostique des cellules dendritiques matures et des lymphocytes CD8+ variait en fonction du statut moléculaire des tumeurs. Nous avons également retrouvé la valeur pronostique de l’environnement immunitaire, représenté par la densité en cellules dendritiques matures et en lymphocytes CD8+, sur la survie à long terme des carcinomes pulmonaires de stade III-N2 opérés après chimiothérapie néoadjuvante. Enfin, nous avons démontré que la chimiothérapie n'est pas associée à de profondes modifications de l’infiltrat immunitaire, alors qu’elle entraîne des modifications des cellules tumorales. L’ensemble de ces résultats suggère que l’infiltrat immunitaire est intimement lié à la cellule tumorale et que la composition du microenvironnement immunitaire varie avec les caractéristiques de la tumeur. Cette interaction entre les cellules tumorales et les cellules immunitaires contribue au pronostic de ces tumeurs. Ces données démontrent l’intérêt d’utiliser des traitements combinant des drogues cytotoxiques, telle la chimiothérapie conventionnelle, à des traitements immunomodulateurs permettant de favoriser une réponse immunitaire anti-tumorale efficace. / The major role of the immune system against tumor development is now clearly established, including lung carcinoma. Nevertheless, interaction between tumoral cells and immune environment is less well-defined. In that study, we have studied morphological and molecular tumoral cells characteristics from lung adenocarcinoma and their role in the composition of immune environment. We reported the prognostic value of morphological parameters, as histological grade of adenocarcinoma, and their association with molecular EGFR and KRAS status. We hypothesized that morphological and molecular diversity of these tumors could be associated with a specific intratumoral immune signature, and could have an impact in prognosis. We showed that mature dendritic cells density, located in tertiary lymphoid structures, differed according to EGFR and KRAS status. Morever, molecular status of tumors modified the pronostic value of mature dendritics cells and CD8+ T cells. We found a prognostic value of immune environment, represented by dendritic cells and T CD8+ cells, in operated stage III-N2 lung carcinomas treated by neoadjuvant chemotherapy. At last, we demonstrated that chemotherapy is not associated with wide modifications in immune infiltrate, whereas it induced modifications in tumoral cells. All together, these data strongly argue for a close link between tumoral cells and immune environment, which seems to depend on tumoral cell characteristics. This interaction between tumoral cells and immune cells contribute to the prognosis of these tumors. These results show the evidence that combine cytotoxic treatment, like conventional chemotherapy, with immunomodulators, favour a protective anti-tumor immune response.
170

Optimalizace postupů pro kvantifikaci miRNA z tenkojehlových bioptických vzorků karcinomu pankreatu. / Optimization of miRNA analysis in fine-needle biopsy samples of pancreatic cancer tissue.

Čuperková, Romana January 2014 (has links)
Pancreatic cancer (PC) is extremely severe malignant disease with a five-year survival of less than 5%. Currently there is no reliable tool for the diagnosis of PC in its early stages. At the time of clinical symptoms most patients are in an advanced stage of the disease and the treatment does not usually have a significant effect. For these reasons emphasis is gradually shifting to the search for the suitable molecular markers for improvement of the diagnosis and assessment of the survival prognosis with respect to a possibility of surgical treatment. MiRNA represent one of the most promising markers, although, their examination in pancreatic tissue is a complicated process. One of the reasons is the very small amount of the source material coming from a fine needle biopsy. A second cause of problems is the subtle character of the pancreatic tissue resulting in significantly lower yields of molecular genetic analysis when compared to other epithelial tissues. An additional negative factor is heterogeneity of the tissue resulting in disproportionate representation of tumor cells within the sample. A suitable choice of procedures for isolation of nucleic acids (NA) and subsequent analysis including quantification of tumor cells is critical for accurate evaluation of the miRNA levels. This work is...

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