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Targeting insulin storage forms in pancreatic β-cell secretory granules
Asai, Seiya ; Jiráček, Jiří (advisor) ; Skořepa, Ondřej (referee) ; Koblas, Tomáš (referee)
In this dissertation, we focused on a comprehensive investigation of insulin production, storage and secretion by pancreatic -cells. We successfully developed a new assay for the rapid and sensitive determination of insulin concentration in biological samples. This assay, based on the competition of the measured sample with a radioligand for the insulin receptor, helped us to determine the influence of several low molecular weight compounds, as well as peptides, on insulin secretion. We found that arginine and ornithine have a dose-dependent stimulatory effect on glucose- stimulated insulin secretion from -cells, but that dopamine inhibits insulin secretion. The effect of serotonin on insulin secretion was ambiguous. We also studied the effects of the bone protein osteocalcin and its fragments on insulin secretion. We found that these peptides do not stimulate insulin secretion from -cells, but that osteocalcin may have proliferative properties. We also tested the effect of tryptophan and its metabolites and found that these compounds do not stimulate insulin secretion but that some of them may inhibit secretion at higher concentrations. An important result of the study is the experimental confirmation of the presence of crystalline insulin in the secretory granules of -cells. This is the first...
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Srovnání poruchových a neporuchových přístupů k teorii optické spektroskopie
Malý, Pavel ; Mančal, Tomáš (advisor) ; Pšenčík, Jakub (referee)
This thesis focuses on the comparison of perturbative and non-perturba-tive calculation of the third order polarization in two dimensional (2D) optical spec- troscopy. A two-level molecule and a coupled dimer are chosen as simple systems for which the 2D spectrum is calculated using explicit equations of motion for the reduced density matrix and integrating the response functions. The two approaches are compared qualitatively and quantitatively using obtained re- sults. The main difference found is the presence of higher order polarization contributions in non-perturbatively calculated spectrum. 1
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Redox Properties of Quasi Dimer of 1,3-diphenylisobenzofuran for Singlet Fission
Šimková, Ludmila ; Ludvík, Jiří
Molecules on the base of 1,3-diphenylisobenzofuran attract an interest because of their\npossible efficiency for singlet fission This study is focused on electrochemical behaviour of\nthe „quasi dimer“ of 1,3-diphenylisobenzofuran. For characterization of reduction mechanism\nin situ UV-vis and EPR spectroscopy were used. The monomer 1,3-diphenylisobenzofuran\nand its CH2 dimer were added to this study for comparison. The redox properties of both\ncompared molecules are similar. The location and the nature of the covalent bridging unit in\nCH2dimer have small effect onthe redox potentials. But the pi-conjugation in the molecule of\nquasi dimer causes approximately 0.2 V easier oxidization and reduction.
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Srovnání poruchových a neporuchových přístupů k teorii optické spektroskopie
Malý, Pavel ; Mančal, Tomáš (advisor) ; Pšenčík, Jakub (referee)
This thesis focuses on the comparison of perturbative and non-perturba-tive calculation of the third order polarization in two dimensional (2D) optical spec- troscopy. A two-level molecule and a coupled dimer are chosen as simple systems for which the 2D spectrum is calculated using explicit equations of motion for the reduced density matrix and integrating the response functions. The two approaches are compared qualitatively and quantitatively using obtained re- sults. The main difference found is the presence of higher order polarization contributions in non-perturbatively calculated spectrum. 1
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