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Regiospecific cyclam derivatives for radiomedical and MRI utilizations
Blahut, Jan ; Kotek, Jan (advisor) ; Drahoňovský, Dušan (referee)
Cyclam (1,4,8,11-tetraazacyclotetradecane) derivatives are widely used for various purposes. In a medicine they are applied as ligands for radiometals applied as diagnostic or therapeutic agents against tumours, hypoxic brain tissues etc. In this thesis a new method for asymmetric cyclam derivati- ves preparation was developed. New cyclam derivatives with trifluoroethyl groups were prepared too. Paramagnetic metal complexes with these fluori- nated ligands can be used as contrast agents for 19 F-MRI. Keywords: Cyclam; Non-symmetric protection; Contrast agents; Trifluoroethylamines; Paramagnetic relaxation; 19 F-MRI.
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Alternative methods for visualization of pancreatic islets.
Gálisová, Andrea ; Jirák, Daniel (advisor) ; Krššák, Martin (referee) ; Kratochvílová, Simona (referee)
Transplantation of pancreatic islets (PIs) represents an alternative treatment for type 1 diabetes mellitus. Post-transplant monitoring of islets by a reliable imaging method may contribute to the improvement of the transplantation outcome. In this thesis, novel visualization approaches for PIs were tested using magnetic resonance (MR) and optical imaging on phantoms and experimental animals, including Chemical Exchange Saturation Transfer (CEST) MR, fluorine (19 F) MR, bioluminescence and fluorescence imaging. MR imaging based on frequency-selective method CEST was performed on islets labeled with Eu-/Yb-based chelates. Labeled islets possessed low MR signal in phantoms, what would have been unsatisfactory for in vivo applications. Moreover, viability and function of labeled islets was impaired reflecting limited applicability of these agents for islet labeling and visualization. Genetically modified bioluminescent islets showed suitable properties for longitudinal tracking of their post-transplant fate at an artificial transplant site - subcutaneously implanted polymeric scaffolds. Using multimodal imaging (MR and bioluminescence), the optimal timing for transplantation of islets into the scaffolds was assessed in diabetic rats. Islets transplanted into scaffolds using the optimized timing scheme...
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Synthesis of beta-cyclodextrin derivatives for medicinal applications
Popr, Martin ; Jindřich, Jindřich (advisor) ; Veselý, Jan (referee)
Synthesis of monosubstituted β-cyclodextrin derivatives for medicinal applications Abstract This thesis is focused on preparation of a set of β-cyclodextrin derivatives with potential use as scaffolds for a construction of novel MRI contrast agents. Firstly, the skeleton of native β-CD was selectively persubstituted at possitions 6 and equipped with azide functions. Per-6-azido-β-CD was then monosubstituted on secondary face of the macrocycle. (E)-cinnamylbromide and propargylbromide were chosen as suitable reagents. The monosubstitution reaction afforded two types of regioisomers, substituted at position 2I -O- or 3I -O-. These regioisomers were sucessfully separated via preparative column chromatography after peracetylation of all free hydroxyl groups. 2I -O-, 3I -O-formylmethyl- and 3I -O- karboxymethyl- analogues were prepared by oxidative transformation of cinnamyl group. Finally the usability of the formylmethyl- derivative for covalent binding with suitable substrate via reductive amination was confirmed. Keywords: cyclodextrins, monosubstitution, cinnamyl, propargyl, formylmethyl, carboxymethyl, reductive amination, MRI, contrast agents
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Contrast agents in radiology
VODRÁŽKOVÁ, Veronika
The aim of this bachelor thesis is a summary of all the information about contrast agents and the making of an information leaflet related to contrast substances applied during radiodiagnostic methods. The theoretical part mentions the history of contrast substances and their division. Further, this part mentions the use of contrast substances in radiodiagnostics. Further, their side effects are summed up, as well as the risks carried along their application. Last but not least, prevention and cure of side reactions are mentioned. The data needed for emphasizing the meaning of the information leaflet was obtained from a quantitative research, and it is given in the practical part. The bachelor thesis research question is, "Are patients fully informed about contrast substances?". The answer to the research question is, according to my survey, "No". The statistical research, based on question No. 7 saying "Was the lesson, given to you by the nursing staff, sufficient?" has proven that 23 %, i.e. 10 respondents out of 48 was happy with the education. The rest of 77 % reported that they wanted more information. The result of this bachelor thesis presents the evaluation, the most significant results, and a possible solution to the given issue.
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Alternative methods for visualization of pancreatic islets.
Gálisová, Andrea ; Jirák, Daniel (advisor) ; Krššák, Martin (referee) ; Kratochvílová, Simona (referee)
Transplantation of pancreatic islets (PIs) represents an alternative treatment for type 1 diabetes mellitus. Post-transplant monitoring of islets by a reliable imaging method may contribute to the improvement of the transplantation outcome. In this thesis, novel visualization approaches for PIs were tested using magnetic resonance (MR) and optical imaging on phantoms and experimental animals, including Chemical Exchange Saturation Transfer (CEST) MR, fluorine (19 F) MR, bioluminescence and fluorescence imaging. MR imaging based on frequency-selective method CEST was performed on islets labeled with Eu-/Yb-based chelates. Labeled islets possessed low MR signal in phantoms, what would have been unsatisfactory for in vivo applications. Moreover, viability and function of labeled islets was impaired reflecting limited applicability of these agents for islet labeling and visualization. Genetically modified bioluminescent islets showed suitable properties for longitudinal tracking of their post-transplant fate at an artificial transplant site - subcutaneously implanted polymeric scaffolds. Using multimodal imaging (MR and bioluminescence), the optimal timing for transplantation of islets into the scaffolds was assessed in diabetic rats. Islets transplanted into scaffolds using the optimized timing scheme...
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Perfusion Modelling in Optical Coherence Tomography
Štohanzlová, Petra ; Penhaker,, Marek (referee) ; Kudrna,, Petr (referee) ; Kolář, Radim (advisor)
This thesis deals mainly with perfusion modeling in optical coherence tomography (OCT). The introductory part deals with basic theory of the OCT, including a description of its basic applications. Part of the work was the testing of selected contrasting materials suitable for the OCT and the design and implementation of phantoms, which were subsequently used in the main part of the thesis. In the practical part, attention is paid to the perfusion analysis in the OCT, first the application of the dilution theory in the OCT for flow estimation, then a study testing the basic theory of perfusion on OCT by means of tissue phantom. Another part of the thesis is devoted to the method of speckle variance analysis for flow visualization.
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Contrast agents for 19F MRI
Koucký, Filip ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
For 19 F MRI the fluorinated contrast agents should be endowed by short relaxation times. Paramagnetic metal ions make relaxation times shorter and this effect depends on the distance between the metal ion and 19 F nuclei. The aim of this thesis is the synthesis of suitable ligand containing fluorine atoms, and a preparation of its Ni2+ and Cu2+ complexes. Macrocyclic 1,4,8,11- tetraazacyclotetradecane (cyclam) was selected as a starting material as it has optimal ring-size for complexation of the selected ions. The parent macrocycle was substituted by fluorine-containing coordinating pendant arms. Key words: Cyclam; Contrast agents; Phosphonic acids, 19 F MRI, Paramagnetic relaxation, d-metals
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Regiospecific cyclam derivatives for radiomedical and MRI utilizations
Blahut, Jan ; Kotek, Jan (advisor) ; Drahoňovský, Dušan (referee)
Cyclam (1,4,8,11-tetraazacyclotetradecane) derivatives are widely used for various purposes. In a medicine they are applied as ligands for radiometals applied as diagnostic or therapeutic agents against tumours, hypoxic brain tissues etc. In this thesis a new method for asymmetric cyclam derivati- ves preparation was developed. New cyclam derivatives with trifluoroethyl groups were prepared too. Paramagnetic metal complexes with these fluori- nated ligands can be used as contrast agents for 19 F-MRI. Keywords: Cyclam; Non-symmetric protection; Contrast agents; Trifluoroethylamines; Paramagnetic relaxation; 19 F-MRI.
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