|
|
Polymeric nanoparticles: platform for poorly water soluble drugs delivery
Roztočilová, Adéla ; Holas, Ondřej (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Mentor: PharmDr. Ondřej Holas, Ph.D. Student: Adéla Roztočilová Title of thesis: Polymeric nanoparticles as a platform for delivery of poorly water-soluble drugs Polymer nanoparticles can be used as drug carriers due to their beneficial properties. One of the advantages of polymeric nanoparticles is, for example, to increase the solubility of drugs in water. They have great potential in the therapy of inflammatory diseases such as Crohn's disease or in shifting cancer pharmacotherapy. The main objective of this thesis was to prepare polymeric nanoparticles with encapsulated curcumin as model active ingredient. Four types of poly(lactic-co-glycolic acid) (PLGA) copolymer were used to prepare the nanoparticles. Nanoprecipitation and emulsion evaporation methods were employed. The parameters evaluated were encapsulation efficiency, drug loading, particle size and polydispersity. Both the water phase, where two different surfactants were employed, and the organic phase were varied during the experiment. The experimental part also used a dissociation method where two types of PLGA copolymer were compared and during the dissociation, samples were taken at predetermined times to determine the total...
|
|
|
Study on the relation between G-quadruplexes and p53-driven regulation
Holotová, Paulína ; Vodička, Juraj (referee) ; Brázda, Václav (advisor)
Táto práca sa zaoberá úlohou štruktúr G-kvadruplexov, ich stabilizáciou pomocou ligandov a úlohou p53 v regulácii transkripcie. G-kvadruplex je typ sekundárnej štruktúry nukleovej kyseliny zloženej z 2 – 4 tetrád. Každá tetráda je tvorená štyrmi guanínmi spojenými prostredníctvom Hoogstenovho párovania báz. Táto práca pozostáva z teoretickej a experimentálnej časti. V teoretickej časti bola opísaná podstata G-kvadruplexových štruktúr a ich potenciál pri liečbe rakoviny, úloha p53 v bunkovom cykle a jeho regulácia a ligandy kurkumín a TMPyP4 použité na stabilizáciu G4. V experimentálnej časti sa študovali interakcie ligandov kurkumínu a TMPyP4 so štruktúrami nukleových kyselín. Reportérové kmene kvasiniek obsahujúce PUMA, KSHV aich kombinácie boli transformované plazmidmi kódujúcimi iba selekčné markery a plazmidmi kódujúcimi divokú formu génu pre proteín p53. V teste životaschopnosti, optimálna koncentrácia ligandov (kurkumínu a TMPyP4) bola stanovená pre reportérový kmeň PUMA, ktorá sa ďalej použila v Luciferázovom teste. Test vytesnenia fluorescenčného indikátora s tioflavínom T ako fluorescenčným farbivom dokázal interakciu medzi oligonukleotidmi tvoriacimi G4 a kurkumínom a TMPyP4. Luciferázový test sa použil na vyhodnotenie interakcie medzi transformovanými reportérovými kmeňmi kvasiniek a oboma ligandmi. Výsledky po 24 hodinách ukázali štatistickú významnosť pre každý kmeň v rovnakom prostredí, pričom kmeň PUMA vykazoval najvyššiu transaktivačnú aktivitu - insert PUMA je cieľovým génom pre p53. Kmene s PUMA aj KSHV vykazovali významne nižšiu transaktivačnú aktivitu, keďže prítomné ligandy mohli stabilizovať štruktúru G4 prítomnú v KSHV, a tým znížiť transkripciu. Prítomnosť G4 v sekvencii KSHV sa potvrdila aj pomocou programu G4Hunter, pričom G4Skóre bolo 3,182. Transaktivácia bola výrazne nižšia aj v kmeňoch PUMA prítomných v prostredí kurkumínu a TMPyP4, aj napriek tomu, že táto sekvencia netvorí G4, čo potvrdil aj program G4Hunter. To naznačuje, že študované ligandy kurkumín a TMPyP4 môžu regulovať metabolizmus buniek iným spôsobom, ako sa doteraz predpokladalo.
|
|
|
Polymeric nanoparticles for poorly water soluble drugs delivery
Nekolová, Martina ; Holas, Ondřej (advisor) ; Smékalová, Monika (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Mentor: PharmDr. Ondřej Holas, Ph.D. Student: Martina Nekolová Title of thesis: Polymeric nanoparticles for poorly water-soluble drugs delivery Polymeric nanoparticles represent a modern drug form. One of the main advantages is influencing the pharmacokinetic properties of the administered substance - e.g. increasing solubility in water. They enable the targeted delivery of the drug to the affected tissue and this way minimize adverse effects. This could be of great benefit to the therapy of cancer or inflammatory diseases. Both the target tissue and the nanoparticles must have some specific properties. For particles, it is, for example, size and surface charge. The aim of this work was to prepare nanoparticles with a substance poorly soluble in water, represented by curcumin. The particles were prepared by the nanoprecipitation method with different types of poly(lactic-co-glycolic acid) (PLGA) copolymer. A 50:50 linear PLGA polymer and a branched PLGA A2 polymer were used. The prepared nanoparticles were compared on several parameters - particle size and polydispersity, encapsulation efficiency (EE), drug-loading capacity (DLC) and dissolution profile. PLGA 50:50 was found to provide...
|
|
| |
|
|
Use of copolymer polyhydroxyalkanoates in development of intelligent packaging
Kreuzerová, Monika ; Kalina, Michal (referee) ; Sedláček, Petr (advisor)
This bachelor thesis deals with the preparation and characterization of copolymers P(3HB-co-4HB). The theoretical part discusses polyhydroxyalcanolates (PHA), where their structure, properties and synthesis are described and subsequently the selected copolymers, which contain monomeric units 3HB, are listed. Furthermore, the review part is processed for the current state of the issue, which states the use of copolymers PHA and current research work on the incorporation of active substances into copolymers. The aim of this work was to characterize and compare the created P(3HB) and P(3HB-co-4HB) foils with a 4HB monomeric unit of 65,25 % and 43,61 % and subsequently determine the potential of foil usability as intelligent packaging materials. First, PHA were subjected to gas chromatography, SEC-MALS, FTIR and DSC analysis. In the second part of the thesis, the permeability of foils to water vapor and the release of model active substances from PHA foils was studied. For this purpose, two active substances (curcumin and salicylic acid) were selected, which were incorporated into a film of homopolymer P(3HB) and two copolymers with a proportion of 4HB of 65,25 % and 43,61 %. In foils prepared from copolymers, the active substances diffusion was faster than in P(3HB). Within the copolymers, P(3HB-co-43,61%4HB) released substances at a higher speed, due to the greater crystallinity of a copolymer containing 65,25 % 4HB.
|
|
|
Adsorption of biologically active substances in colloidal solutions of aminoclay
Málková, Ivana ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This paper builds on a previous study of magnesium aminoclay and its interactions with biological compounds. The theoretical part deals with the research of the usage of aminoclay as a carrier in medical applications, the method of its formulation, the selection of biologically active compounds and a suitable method of varification. The experimental part deals with the synthesis of aminoclay, samples preparation and study of the adsorption behavior of the selected bioactive compounds under different conditions. The experimental part of the paper also includes varification of the suitability of the selected UV VIS spektrometry to determine the adsorption behavior of the biologically active compounds in colloidal aminoclay solutions.
|
|
|
Curcumin in the treatment of traumatic spinal cord injury
Kloudová, Anna ; Machová Urdzíková, Lucia (advisor) ; Martončíková, Marcela (referee)
Spinal cord injury is a very significant clinical as well as social problem with extensive consequences, affecting the patient and also his/her family. Great efforts have been devoted to searching for an effective treatment, which would improve their situation. This thesis evaluated the effects of the natural compound curcumin on spinal cord injury using an experimental balloon compression model. Male Wistar rats were randomized into two groups following the lesion induction, namely vehicle- or curcumin-treated. The behavioral recovery was evaluated using a set of locomotor and sensory tests and a histological and imunohistochemical analysis was performed. The qPCR method was used to observe the expression of some genes related to regeneration and immune response. It was demonstrated that curcumin improved locomotor recovery after the spinal cord injury, particularly in the early stages. Morphometric analysis of the gray and white matter sparing didn't confirm any differences between the two groups. Nevertheless, the glial scar formation was significantly reduced around the central part of the lesion in the curcumin treated group and also the NF-κB activity was substantially inhibited. The gene expression analysis demontrated downregulation of Gfap and Rantes genes and upregulation of the Irf5 gene...
|
|
|
Some aspects of molecular mechanisms of xenobiotics' hepatotoxicity and hepatoprotection : Modulatory roles of natural polyphenols
Lekic, Nataša ; Farghali, Hassan (advisor) ; Kršiak, Miloslav (referee) ; Brůha, Radan (referee)
Background & Aims: Oxidative stress and apoptosis are proposed mechanisms of cellular injury in studies of xenobiotic hepatotoxicity. The aim of this work is to find early signal markers of drug-induced injury of the liver by focusing on select antioxidant/oxidant and apoptotic genes. As well, to address the relationship between conventional liver dysfunction markers and the measured mRNA and protein expressions in the D-galactosamine/lipopolysaccharide and tert-butylhydroperoxide hepatotoxicity models. Furthermore, potential hepatoprotective capabilities of antioxidant polyphenols quercetin and curcumin were evaluated in relation to its modulation of the oxidative stress and apoptotic parameters in the given xenobiotic hepatotoxicity models. Methods: Biochemical markers testing the hepatic function included aminotransferases (ALT, AST) and bilirubin. Measurements of TBARS and conjugated dienes were used to assess lipoperoxidation. Plasma levels of catalase and reduced glutathione were used as indicators of the oxidative status of the cell. Real time PCR was used to analyse the mRNA expressions of the inducible nitric oxide synthase (NOS-2), heme oxygenase-1 (HO-1), superoxide dismutase (SOD-1), glutathione peroxidase (Gpx-1), caspase 3 (Casp3), BH3 interacting domain death agonist (Bid) and Bcl-2...
|
|
|
Disposable sensor of ammonium for intelligent packaging
Nentvichová, Aneta ; Kořínková, Radka (referee) ; Veselá, Mária (advisor)
This diploma thesis is focused on the problematic of the smart packaging and deals with the preparation of disposable ammonia sensors/indicators and the subsequent color measurement of prepared sensors/indicators using the CIE L* a* b* color space. The theoretical part of the diploma thesis focuses on active and intelligent packaging, using ammonia sensors/indicators. The emphasis is placed on the main components of the sensor/indicator, i.e., chitosan as a polymer and curcumin as a dye. The theoretical part also includes the problematic of meat degradation, which plays a very important role in this thesis. The experimental part was divided into two parts. The first part was to prepare layers that will respond in different colors based on the concentrations of ammonia. Prepared layers were sensitive to ammonia across all concentrations, and based on this result, ascorbic acid was applied to compositions to achieve a calibration retention of the selected amount of ammonia. The second minor part of the experiment was the application of selected layers to packages with real meat.
|
|
|
Influence of natural polyphenolic substances on p53 protein expression
Bušanski, Patrik ; Němcová, Andrea (referee) ; Brázda, Václav (advisor)
The tumor suppressor protein p53 is one of the major regulators of the cell cycle after DNA damage. In addition to stopping the cycle and repairing DNA, it can, in extreme cases, induce programmed cell death - apoptosis. Mutations in the gene encoding p53 are present in more than 50% of cancer cases. This thesis examines alternative natural polyphenolic substances that could increase the level and expression of p53 protein in tumor cells. These substances could be an alternative to non-specific cytostatics, which bring many undesirable additional effects during treatment. In the theoretical part of the thesis the structure and properties of the p53 protein and describes alternative therapeutic approaches with a focus on polyphenolic substances is explained. The aim of the experimental part was to determine the effect of curcumin and resveratrol in comparison with often used cytostatic drug, doxorubicin, on cell viability of tumor cells and on p53 protein levels. The effect of these substances on the binding of p53 to DNA in yeast systems was also examined. It was found that doxorubin efficiency is many times higher than the examined polyphenolic agents, but resveratrol was showing some potential as a suitable alternative in the treatment of tumors, thanks to the ability to activate apotosis. It was clearly demonstrated that there is an association between induced programmed death and increased p53 protein expression after resveratrol treatment.
|
guest ::
