Resistance of various cancers to conventional therapies including radio- and chemo- therapy is one of the most investigated phenomena in the molecular and clinical oncology. Recurrent disease is characterized by the presence of metastases, which are responsible for 90% of cancer-related mortality. Fractionated ionizing radiation (fIR) combined with surgery or hormone therapy represent the first-choice treatment for medium to high risk localized prostate carcinoma (PCa). In PCa, the failure of radiotherapy (RT) is often caused by radioresistance and further dissemination of escaping (surviving) cells. To investigate the radioresistance-associated phenotype, we exposed four metastasis- derived human PCa cell lines (DU145, PC-3, LNCaP, and 22RV1) to clinically relevant daily fractions of ionizing radiation (fIR; 35 doses of 2 Gy) resulting in generation of two surviving populations: adherent senescent-like cells expressing common senescence-associated markers and non-adherent anoikis-resistant stem cell-like cells with active Notch signaling and expression of stem cell markers CD133, Oct-4, Sox2, and Nanog. While the radioresistant adherent cells were capable to resume proliferation shortly after the end of irradiation, the non- adherent cells started to proliferate only after their reattachment...

The aim of this diploma thesis is the design of linear accelerator for oncology treatment. The design focuses on the improvement of the aesthethical side of the accelator, but also comes up with inventional solutions how to improve the radiation treatment of oncology patients to higher the chances of successful treatment of cancer.

This diploma thesis deals with the elaboration of managed documentation for yearly Short-term Stability Check of the planning system and identification of critical points, which refer to their lack of security. Documentation of Short-term Stability Check is specified for use with the Eclipse Planning System from Varian Medical Systems, at the Oncology Department of the České Budějovice Hospital, a. s. In the theoretical part, I focused on producing managed documentation and innovations in the sphere of planning system. I described also the cyber security that relates to one of my targets. At first in the practical part I elaborated a draft of managed document for Short-term Stability Check of the planning system based on the internal directive of the České Budějovice Hospital, a.s. The draft will become the managed document after the approval process. Furthermore, in the practical part are defined the most critical points of the methodology, which could have a negative impact on the safely functioning planning system and the whole department in general. Subsequently I analyzed the risk using the KARS method. After evaluation of critical points I described how they are secured and where are situated deficiencies. Measures were proposed based on results of the analysis for their protection. The benefit of this work is a new perspective on the issue of safe using. This analysis shows an expansive concept of safety in using the planning system with an impact on the operation of the entire department.

The introductory part of the diploma thesis primarily focuses on the history of radiotherapy, i.e. what it emerged from and how it developed, as it is one of the most important fields in medicine, especially because thousands of people are irradiated every day due to different tumour and non-tumour diseases. Another reason why ionizing radiation is described is the fact that it is a necessary part of tumour disease irradiation. Ionizing radiation is also connected with radiation protection. This section presents a historical overview of radiation protection, as well as principles and quantities of this field. Furthermore, it focuses on Czech acts, decrees, and government regulations which define various measures governing this issue. Radiation protection forms the basis of patient, workplace, and personnel monitoring. All this is connected with the measurement and evaluation of received personal doses. This brings the thesis to the field of dosimetry, therefore various dosimeters used in practice are described. The aim of this diploma thesis is the measurement of patients? personal doses in head and neck irradiation using the electronic personal dosimeter at the radiotherapy centre of Nemocnice České Budějovice, a. s. The thesis is based on the question of whether irradiation doses that patients with head and neck tumours receive outside the primary radiation beam are negligible. The theoretical part of the thesis uses all available resources from both foreign and Czech literature. The practical part is based on numerical statistics, i.e. a quantitative method. The research was carried out at the radiotherapy centre of Nemocnice České Budějovice, a. s. Irradiation of patients with head and neck tumours was performed on a linear accelerator. Each patient had a mask to which an electronic personal dosimeter was attached during irradiation. Using this dosimeter, it was possible to measure doses received outside the central radiation beam. The measured values were then used to carry out assessment using formulas. Patients who undergo cancer treatment receive relatively high doses of radiation, so my main goal was to measure personal dose equivalents at the reference point. When comparing the percentage of the number of examinations with the web portal Epidemiology of Malignant Tumours in the Czech Republic, it was found that irradiation of the neck is more frequent than irradiation of the head. The total values of personal dose equivalents are relatively high in each patient, but because it is medical treatment, these values are not subject to radiation exposure limits. The comparison of the irradiated areas shows that irradiation of the neck has small values of personal dose equivalents to 1Gy compared to irradiation of the head.

The thesis is based on the need of workplaces, where ionizing radiation sources are used, to implement a new legislation in the field of the Atomic Act effective since 1st January 2017. The thesis is focusing specifically on Radiation accidental exposures and radiation emergency on selected radiotherapeutic departments with linear particle accelerator. The theoretical part deals with definitions and categorization of radiation accidents and radiation emergency, relevant legal requirements and related work documentation related to this issue. The practical part deals with the evaluation of specific documents processed at two radiotherapeutic departments, the outcome of which is a proposal for their revision, which in agreement with the requirements of the new legislation and submitted for SÚJB´s approval. Primarily, for this purpose, it is a part of the practical part to create data file of actual radiation accidents and radiation emergencies in two specific workplaces and to analyze the causes of their occurrence. An interesting element is the choice of workplaces with a different producer of a linear accelerator, where are only two companies on the market. This choice was intend to determine whether the root causes of radiology accidents can have a causal link in relation to the technology in question of SW or accessories of the producer. The aim of the analysis is, in any case, awareness, prevention and iterative removal of the causes of accidents and the adoption of such measures in order to avoid any recurrence of events already occurred. All precautionary and follow-up measures, including responsibilities and competences, must be documented in the documentation of departments, with each holder of the resource authorization being required to keep this documentation in agreement with practice and current legislation. The thesis contributes to the detection of the causes of the accidents and the revision of the related documentation in order to be in agreement with the actual situation in the given depratments.

The task of this thesis is to familiarize readers with the basics of the problem of ionizing radiation from its types and resources, through mechanisms of action and its effects on the human organism, to the possibility of calculating various characteristics. Close attention is paid to the use of ionizing radiation in medical approaches. There is in detail described process of radiotherapy planning and a basic properties of planning systems. Part of the thesis is also program RT-Plan processed in Matlab. The program simulates the planning system for external ionizing radiation therapy used in treatment. There is supplemented a detailed help and series of tests for the plan. It is suitable for possible use in teaching.

1 Abstract This doctoral thesis is focused on the synthesis and characterization of novel hybrid polysaccharide-based polymers applicable for biomedicine, specifically for a conceptually new bimodal cancer treatment - immunoradiotherapy. For this purpose, polysaccharides β-glucan from Auricularia auricula-judae and κ-carrageenan from Kappaphycus alvarezii, exhibiting immunostimulatory and anticancer activities, were chosen to be grafted with thermoresponsive poly(2-isopropyl-2-oxazoline-co-2-butyl-2-oxazoline)s (POXs) (with different graft lengths and grafting densities) that induced a lower critical solution temperature of the final polymers. The thermoresponsive behavior of resulting polymers was studied with temperature-dependent light scattering methods, fluorescence measurements and also nuclear magnetic spectroscopy to select a polymer material with the most suitable properties for the intended application, aiming at a polymer depot formation after the injection of a polymer solution into the body. The chosen polymer, β-glucan-graft-POX with graft length of 2500 Da, was then modified to bear 1,4,7,10-tetraazacyclododecane-1,4,7,10- tetraacetic acid and a fluorescent dye Dyomics-615 at the graft ends and tested first in vitro to investigate its immunostimulatory properties and also the cellular uptake....

This project deals with the issue of simulation of dose irradiation. This principle is used in a radiotherapeutic device known as a Leksell Gamma Knife for the treatment of intracranial tumours. With regard to the theoretical observations obtained by studying this device, the project suggests the use of analytical geometry for the creation of a mathematical model for calculation of the intensity in the rayed area. A demonstration program Leksell_xvecer08 has been created for this model in a MatLab software background, which enables the user to change various input arguments and simulate a picture of the dosage spread in the target scanned areas.