National Repository of Grey Literature 80 records found  beginprevious21 - 30nextend  jump to record: Search took 0.01 seconds. 
Possibilities of affecting secondary metabolites production in "in vitro" cultures of medicinal plants
Sojková, Kristýna ; Tůmová, Lenka (advisor) ; Martin, Jan (referee)
1 ABSTRACT Possibilities of affecting secondary metabolites production in in vitro cultures of medicinal plants Elicitation is one of the methods used for increasing the production of secondary metabolites.The aim of this work was to affect the flavonoid production in callus and suspension cultures of St. John's Wort (Hypericum perforatum L.). Abiotic elicitor selendioxide in various concentrations (9.012.10-3 mol/l; 9.012.10-4 mol/l; 9.012.10-5 mol/l) was added in in vitro culture. The content of flavonoids was determinated by high performance liquid chromatography (HPLC). The samples were taken after 6, 12, 24, 48, 72, 168 hours after elicitor treatment. Selendioxide raised the production of hyperoside and quercitrin. The highest content of hyperoside (0.2 %) was detected after selendioxide (in concentration of 9.012.10-3 mol/l) treatment and 168 hours sampling in suspension culture. The highest production of quercitrin (0.37 %) was reached after selendioxide treatment (in concentration of 9.012.10-3 mol/l) and 6 hours sampling also in suspension culture. Production of flavonoids in callus cultures wasn't so much affected in comparison with suspension cultures after elicitor treatment. Flavonoid releasing into nutrient medium was also studied. The highest content of hyperosid (1.02 mg/100ml) was found in...
Study of the surfactants effect on polymer nanoparticle parameters
Moravcová, Katarína ; Holas, Ondřej (advisor) ; Šnejdrová, Eva (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Katarína Kostíková Title of thesis: Study of the surfactants effect on polymer nanoparticle parameters The main aim of this Diploma thesis was to examine whether the use of various stabilizers has any effect on the resultant size of prepared nanoparticles and to find out which type of stabilizer is the most appropriate in terms of preparation of the nanoparticles of the necessary size, adequate polydispersity and steadiness. The preparation of nanoparticles was based on the use of sodium cholate as a surfactant and polymer PLGA (poly (lactid-co-glycolic acid)) consisting of monomers of lactic and glycolic acids. Nanoparticles were prepared by means of nanoprecipitation method. Sodium cholate solution has always been prepared in water in different concentration: 0.005%, 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 1%, 2%, and 5%. The following have been used as stabilizers: poloxamer 407, polyvinyl alcohol, cetrimonium-bromide (CTAB), and polysorbate 20, all of them in concentration of 0.1% and sorbitan-monostearate in concentration of 0.01%. Measurement of the size of created nanoparticles was performed using the device Zetasizer at the...
Preparation of polymeric fluorescent nanopyrticles
Širajová, Daniela ; Holas, Ondřej (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Daniela Širajová Title of thesis: Preparation of polymeric fluorescent nanoparticles Nanoparticles based on biodegradable polyesters are a widely used platform for targeted drug delivery and subsequent controlled release. The aim of this diploma thesis was to prepare and optimize the preparation of polymeric nanoparticles with a fluorescent dye as a model substance. The nanoprecipitation method was used to prepare the nanoparticles. Nanoparticles prepared from two types of PLGA polymers (COOH terminated and ester terminated) were evaluated and compared. The surfactant and stabilizer were used in various concentration ratios to optimize the preparation. The surfactant was sodium cholate at concentrations of 0.1%, 0.5%, 1%, 2% and 5%. The nanoparticles were stabilized with Pluronic F-127 poloxamer at concentrations of 0.1%, 0.5% and 1%. Nanoparticles were compared in terms of encapsulation efficiency, particle size and zeta potential. In a dissolution experiment, the amount of fluorescein released was evaluated and compared as a function of time (48 hours) with acid-terminated PLGA and sodium cholate at concentrations of 0.1% and 2%....
The in vitro effects of selected substances on isolated rat aorta
Beránková, Anna ; Pourová, Jana (advisor) ; Vopršalová, Marie (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Anna Beránková Supervisor: PharmDr. Jana Pourová, Ph.D. Title of diploma thesis: The in vitro effects of selected substances on isolated rat aorta Flavonoids are a numerous group of secondary plant metabolites. Flavonoid compounds are substances widely extended in nature and many of them have a positive influence on human health, primarily for their vasodilatory, antioxidant and anti- inflammatory effects. Three substances were selected for this diploma theses: two substances of isoflavonoid group, genistin and genistein, and the end product of genistein metabolism, 4-ethylphenol. The aim of this work is examination of vasorelaxant effects of this substances in vitro. Vasorelaxing potential of tested substances was tested in vitro in isolated aortic rings of Wistar rat. The effect of increasing doses of individual substances in precontracted aortic rings with intact endothelium was measured. From the obtained values of vessel tension, the DRC curves and EC50 values were created. The results were evaluated. The results analysis shows, that genistein (EC50 2,903.10-5 M) had the most significant activity. Also genistin (EC50 4,045.10-4 M) and high doses of 4-ethylphenol (EC50 1,509.10-3 M) caused...
Search of effective cobalt chelators - 8-hydroxyquinolines
Pelnářová, Karolína ; Mladěnka, Přemysl (advisor) ; Carazo Fernández, Alejandro (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Karolína Pelnářová Supervisor: Prof. Přemysl Mladěnka, PharmD., Ph.D. Consultant: Václav Tvrdý, MSc.; Marcel Hrubša, MSc. Title of diploma thesis: Searching of effective cobalt chelators - 8-hydroxyquinolines Cobalt is one of the essential trace elements present in the human body. It forms a part of the organometallic complex of vitamin B12, which is essential for many physiological functions. Both overload and lack of cobalt in the body is associated with pathological conditions. Manifestations of deficiency can lead up to pernicious anemia or hypofunction of the thyroid gland. Cobalt intoxication can occur in an industrial environment, such as by cobalt metal dust during heavy metal processing, or by its release due to corrosion from orthopedic prostheses. Systemic toxicity is manifested by a number of endocrine, cardiovascular and neurological symptoms. The main aim of this diploma thesis was to find effective chelators of cobalt from the group of substances derived from 8-hydroxyquinoline. In vitro spectrophotometric measurement was used to determine the degree of chelation. The effect of chelation was also monitored ex vivo in rat erythrocytes. All tested chelators - 8-hydroxyquinoline,...
The impact of synthetic chelators from the group of 4-acylpyrazole-5-ones on alcohol dehydrogenase
Sobolová, Zuzana ; Mladěnka, Přemysl (advisor) ; Jirkovský, Eduard (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zuzana Sobolová Supervisor: Prof. Přemysl Mladěnka, Pharm.D., Ph.D. Consultant: Marcel Hrubša, MS.c. Title of diploma thesis: The impact of synthetic chelators from the group of 4-acylpyrazole-5-ones on alcohol dehydrogenase Inhibitors of alcohol dehydrogenase play a key role in the treatment of poisoning caused by methanol, ethanol, ethylene glycol, and their toxic metabolites. Such treatment can therefore be considered as life-saving. In clinical practice, a single substance, fomepizole, is used. This thesis is aimed at investigation of the effect of eleven experimental chelators from the 4- acylpyrazol-5-ones group on equine and yeast alcohol dehydrogenases, and the possible definition of structural features that would be the most suitable for interaction with this enzyme. Due to the ability of these substances to chelate zinc ions, it is believed that they could inhibit an enzyme that has a zinc molecule in the structure. The measurement itself is based on principle of increase in absorbance during the enzymatic reaction, which is caused by the formation of NADH. This measurement is relatively simple, efficient and, due to used kinetic method, also less susceptible to be affected by...
Study of the surfactants effect on polymer nanoparticle parameters
Kostíková, Katarína ; Holas, Ondřej (advisor) ; Šnejdrová, Eva (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Katarína Kostíková Title of thesis: Study of the surfactants effect on polymer nanoparticle parameters The main aim of this Diploma thesis was to examine whether the use of various stabilizers has any effect on the resultant size of prepared nanoparticles and to find out which type of stabilizer is the most appropriate in terms of preparation of the nanoparticles of the necessary size, adequate polydispersity and steadiness. The preparation of nanoparticles was based on the use of sodium cholate as a surfactant and polymer PLGA (poly (lactid-co-glycolic acid)) consisting of monomers of lactic and glycolic acids. Nanoparticles were prepared by means of nanoprecipitation method. Sodium cholate solution has always been prepared in water in different concentration: 0.005%, 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 1%, 2%, and 5%. The following have been used as stabilizers: poloxamer 407, polyvinyl alcohol, cetrimonium-bromide (CTAB), and polysorbate 20, all of them in concentration of 0.1% and sorbitan-monostearate in concentration of 0.01%. Measurement of the size of created nanoparticles was performed using the device Zetasizer at the...
Search of effective cobalt chelators - 8-hydroxyquinolines
Pelnářová, Karolína ; Mladěnka, Přemysl (advisor) ; Carazo Fernández, Alejandro (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Karolína Pelnářová Supervisor: Prof. Přemysl Mladěnka, PharmD., Ph.D. Consultant: Václav Tvrdý, MSc.; Marcel Hrubša, MSc. Title of diploma thesis: Searching of effective cobalt chelators - 8-hydroxyquinolines Cobalt is one of the essential trace elements present in the human body. It forms a part of the organometallic complex of vitamin B12, which is essential for many physiological functions. Both overload and lack of cobalt in the body is associated with pathological conditions. Manifestations of deficiency can lead up to pernicious anemia or hypofunction of the thyroid gland. Cobalt intoxication can occur in an industrial environment, such as by cobalt metal dust during heavy metal processing, or by its release due to corrosion from orthopedic prostheses. Systemic toxicity is manifested by a number of endocrine, cardiovascular and neurological symptoms. The main aim of this diploma thesis was to find effective chelators of cobalt from the group of substances derived from 8-hydroxyquinoline. In vitro spectrophotometric measurement was used to determine the degree of chelation. The effect of chelation was also monitored ex vivo in rat erythrocytes. All tested chelators - 8-hydroxyquinoline,...
Preparation of polymeric fluorescent nanopyrticles
Širajová, Daniela ; Holas, Ondřej (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Daniela Širajová Title of thesis: Preparation of polymeric fluorescent nanoparticles Nanoparticles based on biodegradable polyesters are a widely used platform for targeted drug delivery and subsequent controlled release. The aim of this diploma thesis was to prepare and optimize the preparation of polymeric nanoparticles with a fluorescent dye as a model substance. The nanoprecipitation method was used to prepare the nanoparticles. Nanoparticles prepared from two types of PLGA polymers (COOH terminated and ester terminated) were evaluated and compared. The surfactant and stabilizer were used in various concentration ratios to optimize the preparation. The surfactant was sodium cholate at concentrations of 0.1%, 0.5%, 1%, 2% and 5%. The nanoparticles were stabilized with Pluronic F-127 poloxamer at concentrations of 0.1%, 0.5% and 1%. Nanoparticles were compared in terms of encapsulation efficiency, particle size and zeta potential. In a dissolution experiment, the amount of fluorescein released was evaluated and compared as a function of time (48 hours) with acid-terminated PLGA and sodium cholate at concentrations of 0.1% and 2%....
Deposition of inhaled particles in a model of child lungs
Čederle, Jakub ; Pokorný, Jan (referee) ; Lízal, František (advisor)
This thesis presents a summary of research of deposition of inhaled particles in children’s respiratory system which was mainly conducted on realistic model of children's lungs. Experimental part introduces BUT model representing airways of 5-years-old child which served for measurements of regional deposition. Bachelor's thesis furthermore sums up basic knowledge of respiratory system and points out anatomical and physiological differences between children and adults in given field. There are described basic deposition mechanisms and their impact on aerosol therapy as well.

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