National Repository of Grey Literature 19 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Preparation of nanoparticles and nanofibers for application in anti-acne products
Tilšarová, Kamila ; Veselá, Mária (referee) ; Skoumalová, Petra (advisor)
The diploma thesis was focused on the preparation and characterization of nanoparticles and nanofibres with active substances from chosen herbs with the aim to apply this materials to the products against acne. Various types of extracts were tested on the content of polyphenols, flavonoids and antioxidation activity. These extracts were encapsulated to the liposomes and fibres of polyhydroxybutyrate. Prepared liposomes and fibres were tested mainly on antioxidation activity and antimicrobial activity against the strain Propionibacterium acnes. Then, liposomes were applied to cosmetic emulsions. These creams reported high antioxidation activity and excellent stability determined by analytical centrifugation. Prepared nanofibres also reported high antioxidation activity and antimicrobial effect as well. Finally, particles and fibres were tested in contact with human cells. In appropriate concentration, there was no cytotoxic effect and tested materials can be used in applications on problems with acne.
Natural drugs in cancer treatment and their cytotoxicity
Hájková, Tereza ; Raudenská, Martina (referee) ; Provazník, Ivo (advisor)
The thesis deals with the natural substances in context with the cancer disease. The natural substances have a positive effect on the human organism and they are able to influence the viability and the growth of the cancer cells. The main mechanical device is to influence the mechanisms needed to start the apoptosis of the cancer cells and stopping further proliferation. The cancer cell lines utilization in the cancer disease is discussed in the thesis too. The thesis states common methods of determining the natural substances cytotoxicity. For the experimental part of the thesis it was chosen the MTT test method and the xCELLigence system for monitoring in real time. The mechanical device of the tested substance capsaicin in application on the prostate cell lines, tumorous PC3 and nontumorous PNT1A influence will be observed within the experimental part of the thesis.
Synthesis of quantum dots for in-vivo imaging
Ferdusová, Helena ; Majzlíková, Petra (referee) ; Pekárková, Jana (advisor)
The aim of this work was to synthesise water-soluble QDs using different precursors and stabilizers and to determine the toxicity of the synthesized QDs by in vivo imaging. Experiments were performed on water-soluble QDs (MPA-CdTe, MPA-CdTe/ZnS, MSA-CdTe, MSA-CdTe/ZnS, GSH-CdTe, GSH-CdTe/ZnS, TGA-CdTe, TGA-CdTe/ZnS, GSH-ZnSe and GSH-ZnSe/ZnS ) and toxicity was measured. Synthesized QDs were characterized by high intensity (fluorescence spectroscopy), FWHM and zeta potential (ZS Zetasizer) were selected due to their suitability for this task. The toxicity of QDs was determined by the MTT assay on the cell line HEK 293. The experiments show that a core/shell structure is less toxic than a core structure. The results indicate that the toxicity of our synthesized QDs is the lowest for MPA-CdTe (core structure) and MPA-CdTe/ZnS (core/shell structure).
Analysis and characterization of beta-glucans from some natural sources
Vít, Radek ; Hudečková, Helena (referee) ; Márová, Ivana (advisor)
The aim of the bachelor thesis is to test and characterize commercially available products with declared -glucans content. The theoretical part describes -glucans, their possible sources, properties and utilization. Further, the theoretical part is focused on methods for determination of -glucan content. Saccharomyces cerevisiae yeast and oyster mushroom fungus are available as commercial sources of -glucans. Next individual groups of the active substances and principles of the methods used for their characterization are described too. In experimental part of this work the extracts from five commercially available sources of -glucans were prepared and characterized. Antioxidant activity, total polyphenols, proteins and carbohydrates were determined. For selected products, the content of vitamin C using HPLC and the lipid content using GC-FID were determine as well. An enzymatic method was used to determine the -glucan content. Two samples of the highest antioxidant activity were then subjected to antimicrobial and MTT tests.
Preparation of organic fibers with the addition of algae extracts
Tuhrinská, Terézia ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
The presented bachelor thesis is focused on the preparation and characterization of organic fibers with an admixture of pre-prepared extracts of microalgae and cyanobacteria containing valuable active compounds. The theoretical part describes selected metabolites of microalgae and cyanobacteria, methods of their analysis, the issue of encapsulation and incorporation of active substances into nanofibers and presents some methods of their preparation. In the experimental part of this thesis, selected strains from the CCALA collection were first cultured. Subsequently, aqueous, ethanol and hexane extracts of biomass from cultured and commercial microalgae and cyanobacteria were prepared. The prepared extracts were spectrophotometrically evaluated in terms of the concentration of chlorophylls, carotenoids, antioxidants, polyphenols, and total proteins present. In addition, 96 % ethanol extracts were subjected to more accurate analysis of chlorophylls and carotenoids by HPLC. The highest antioxidant activity was observed for aqueous extracts. Gelatin nanofibers containing selected extracts were formed by electrospinning method. The formed fibers were examined afterwards to identify a mass fraction of incorporated microalgal and cyanobacterial substances. The fibers were further tested for antioxidant activity with the TEAC assay. The most pronounced antioxidant effect was detected for the fiber with incorporated aqueous extract of the cyanobacterium Arthrospira maxima. Finally, the fibers were tested for their safety in contact with human cells. The amount of fibers used did not show any cytotoxic effect on human keratinocytes and the tested materials can thus be considered safe for application in cosmetics.
Interaction of animal cells with organic semiconductors
Schildová, Veronika ; Thalerová, Sandra (referee) ; Víteček,, Jan (advisor)
This bachelor´s thesis was focused on study of biocompatibility of organic semiconductors. In introduction, organic semiconductors and their properties, benefits and features of selected representatives were described. In the following part biocompatibility definition and approaches for its assays including tests of cytotoxicity, material stability were presented. The last part was focused on overview of cell cultures, appropriate cultivation conditions and compounds of media for in vitro testing of biocompatibility. Experimental part showed the result of biocompatibility testing of materials. For this purpose murine 3T3 fibroblasts were used.
Preparation and characterization of modern wound covers
Balášová, Patricie ; Pernicová, Iva (referee) ; Skoumalová, Petra (advisor)
This diploma thesis is focused on the study of bioactive wound dressings. During the thesis, hydrogel, lyophilized and nanofiber wound dressings were prepared. Hydrogel and lyophilized wound dressings were prepared on basis of two polysaccharides – alginate and chitosan. Nanofiber wound dressings were prepared by spinning polyhydroxybutyrate. All prepared wound dressings were enriched with bioactive substances, which represented analgesics (ibuprofen), antibiotics (ampicillin) and enzymes (collagenase). Into hydrogel and lyophilized wound dressings were all the mentioned active substances incorporated, whereas nanofiber wound dressings were only with ibuprofen and ampicillin prepared. The theoretical part deals with the anatomy and function of human skin. There was explained the process of wound healing and also there were introduced available modern wound dressings. The next chapter of the theoretical part deals with materials for preparing wound dressings (alginate, chitosan, polyhydroxybutyrate) and with active substances, which were used during the experimental part of this thesis. In the theoretical part, the methods of preparation of nanofiber wound dressings and also the methods of cytotoxicity testing used in this work were presented. The first part of the experimental part of this thesis was focused on preparing already mentioned wound dressings. Then, their morphological changes over time and also the gradual release of incorporated active substances into the model environment were monitored. The gradual release of ampicillin was monitored not only spectrophotometrically, but also by ultra-high-performance chromatography. In wound dressings, in which collagenase was incorporated, was also the final proteolytic activity of this enzyme monitored. The effect of the active substances was observed on three selected microorganisms: Escherichia coli, Staphylococcus epidermidis and Candida glabrata. The cytotoxic effect of the active substances on the human keratinocyte cell line was monitored by MTT test and LDH test. A test for monitoring the rate of wound healing – a scratch test – was also performed.
Processsing of food supplements based on medical types of mushrooms
Vetchá, Vendula ; Uhlířová, Renata (referee) ; Hoová, Julie (advisor)
This diploma thesis deals with the characterization of nutrition substances in medical mushrooms, specifically Ganoderma lucidum and Hericium erinaceus. It also focuses on the biological impact of these rare mushrooms on human cell lines HaCaT and Caco-2, and investigates the production of pro-inflammatory cytokines IL-6 and IL-8 by immortalized keratinocytes and colon cancer cells after exposure to aqueous extracts prepared from mushroom powder. The theoretical part of the thesis deals with the characterization of mushrooms in terms of morphological characteristics and their taxonomic classification. It further studies the effects of edible and medicinal species and provides a detailed description of medicinal mushrooms such as Ganoderma lucidum, Lentinula edodes, Flammulina velutipes, Grifola frondosa, Hericium erinaceus and Pleurotus ostreatus, thesis informing about their effects, utilization and possibilities for application in the food and pharmaceutical industries. It mentions possible negative effects of mushrooms on consumers' health and presents methods for processing mushrooms and their use in the food industry. Finally, it focuses on the possibilities of in vitro toxicity testing and provides a brief overview of commonly used cytotoxicity tests such as the MTT test and LDH test. The experimental part of the thesis deals with the preparation of water extracts from mushroom powders and their characterization in terms of nutritional and biologically active substances. HPLC analysis is used to monitor the content of lipophilic substances and vitamin C in mushroom samples. To confirm the biological effect on human health, antimicrobial tests were performed using four model microorganisms, and cytotoxicity tests were performed on two human cell lines. Lastly, a sensory analysis of instant vegetable soup enriched with mushroom powder was performed. Biological effects of the analyzed powdered extracts from Ganoderma lucidum mushroom have been confirmed, especially their cytotoxic effect on colon epithelial tumor cells. However, the application of reishi in the food industry is not easy due to the presence of triterpenoids that cause a bitter taste. On the other hand, the safety of using the Hericium erinaceus mushroom in food has been confirmed through cytotoxicity tests. Sensory analysis results have shown a positive effect of Hericium erinaceus on the taste profile of instant vegetable soups.
In vitro cytotoxicity study of selected antimycobacterial substances on human hepatocytes
Klimová, Miroslava ; Kuchařová, Monika (advisor) ; Smutná, Lucie (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: Miroslava Klimová Supervisor: Mgr. Monika Kuchařová, Ph.D. Consultant: Mgr. Pavel Bárta, Ph.D. Title of diploma thesis: In vitro cytotoxicity study of selected antimycobacterial substances on human hepatocytes Clinical research is constantly progressing, new, missing drugs are being searched for, more effective substances are being synthesized, adverse effects are being minimized. The aim of this thesis was to determine the effect of ten substances (JZ195, JZ186, MH17, JZ178, MH9, MH18, JZ177, JZ170, JZ172, JZ174) in the HepG2 cell line and evaluate their cytotoxic potential. The tested substances were derived from the structure of pyrazine-2- carboxamide and synthesized within the Department of Organic and Bioorganic Chemistry at the Faculty of Pharmacy in Hradec Králové, Charles University and developed for the purpose of having promising effect on mycobacterial strains. Cytotoxicity was evaluated in vitro by CellTiter96® AQueous One Solution Cell Proliferation Assay, commercially available colorimetric method based on reduction of the tetrazolium salt to a violet-coloured formazan which directly reflects the number of viable cells. We assessed the hepatotoxic effect using the IC50...
Preparation and characterization of modern wound covers
Balášová, Patricie ; Pernicová, Iva (referee) ; Skoumalová, Petra (advisor)
This diploma thesis is focused on the study of bioactive wound dressings. During the thesis, hydrogel, lyophilized and nanofiber wound dressings were prepared. Hydrogel and lyophilized wound dressings were prepared on basis of two polysaccharides – alginate and chitosan. Nanofiber wound dressings were prepared by spinning polyhydroxybutyrate. All prepared wound dressings were enriched with bioactive substances, which represented analgesics (ibuprofen), antibiotics (ampicillin) and enzymes (collagenase). Into hydrogel and lyophilized wound dressings were all the mentioned active substances incorporated, whereas nanofiber wound dressings were only with ibuprofen and ampicillin prepared. The theoretical part deals with the anatomy and function of human skin. There was explained the process of wound healing and also there were introduced available modern wound dressings. The next chapter of the theoretical part deals with materials for preparing wound dressings (alginate, chitosan, polyhydroxybutyrate) and with active substances, which were used during the experimental part of this thesis. In the theoretical part, the methods of preparation of nanofiber wound dressings and also the methods of cytotoxicity testing used in this work were presented. The first part of the experimental part of this thesis was focused on preparing already mentioned wound dressings. Then, their morphological changes over time and also the gradual release of incorporated active substances into the model environment were monitored. The gradual release of ampicillin was monitored not only spectrophotometrically, but also by ultra-high-performance chromatography. In wound dressings, in which collagenase was incorporated, was also the final proteolytic activity of this enzyme monitored. The effect of the active substances was observed on three selected microorganisms: Escherichia coli, Staphylococcus epidermidis and Candida glabrata. The cytotoxic effect of the active substances on the human keratinocyte cell line was monitored by MTT test and LDH test. A test for monitoring the rate of wound healing – a scratch test – was also performed.

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