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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Alkaloidy Vinca minor L. a jejich biologická aktivita VIII. / Vinca minor L. alkaloids and their biological activity VIII.

Hojgrová, Veronika January 2021 (has links)
V. Hojgrová: Alkaloids of Vinca minor L. and their biological activity VIII. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany. Number of pages 69. This diploma thesis deals with the isolation of alkaloids from Vinca minor L. from the family Apocynaceae. Separation of alkaloids from the selected fraction (VM 215-258) or from their subfractions (VM 34-41, VM 86, VM 87-113) was performed by preparative TLC. Two pure alkaloids were isolated from the subfraction (VH 34-41). The first VH-1 alkaloid not yet isolated and the second VH 2 alkaloid: (-)-raucubainin. Alkaloids were identified by EI-MS, LC-MS, NMR and optical rotation and were compared with data in the literature. Isolated alkaloids were tested for acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and prolyloligopeptidase (POP) inhibitory activity and for cytotoxicity. Both substances did not show significant cholinesterase inhibitory activity IC50 against AChE after measurement, only (-)-raucubainin showed a slight activity against BuChE (IC50 = 94 ± 7 μM), VH-1 was found to be inactive (IC50 > 100 μM). POP inhibitory activity has so far only been tested for (-)-raucubainin; was found to be inactive (IC50 > 1000 µM). The results of the cytotoxic activity of the alkaloids...
32

Alkaloidy Vinca minor L. a jejich biologická aktivita I. / Vinca minor L. alkaloids and their biological activity I.

Jurkaninová, Martina January 2019 (has links)
1 9 ABSTRACT Jurkaninová, M.: Vinca minor L. alkaloids and their biological activity I. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019 The aim of this thesis was the isolation of alkaloids from selected fraction 3 (joined fractions (15 - 36), which was a sub-fraction of the fraction VM 323 - 327. It was obtained from the previous processing of an alkaloidal extract from the Vinca minor L at the Department of Pharmaceutical Botany as a part of elaboration of diploma thesis of Aneta Vítavcová.[78] The fraction VM 323-327 was separated by column chromatography on silica gel and a totally, of 7 subfractions were obtained. Subsequent repeated processing of the selected sub-fraction 3 (15 - 36) by preparative TLC on silica gel resulted in the isolation of (-)-vinoxine and its racemate (±)-vinoxine. Identification of their structure was determined based on MS, NMR and optical rotation. The inhibitory activity against acetylcholinesterase, butyrylcholiesterase and prolyl oligopeptidase were determined for the isolated substances. Inhibitory activity against selected enzymes was measured by spectrophotometric methods. Isolated alkaloids were required to be inactive against AChE and POP (IC50 >1000 μM), against to BChE showed a...
33

Úloha vrozené a získané imunity v imunoterapii melanomu a pankreatického adenokarcinomu

NEDBALOVÁ, Pavla January 2017 (has links)
This study examines the role of innate and adaptive immunity in the immunotherapy based on the combination of the ligands stimulating phagocytosis anchored in the tumour cells membrane and the mixture of TLR agonists. This immunotherapy is primarily focused on the innate immunity activation and induces strong inflammatory infiltration, which neutrophils and NK cells are part of. Therefore, the next aim of this study was to evaluate the anti-tumour activity of neutrophils and NK cells. For examination malignant melanoma and pancreatic adenocarcinoma mouse tumour models were used.
34

Alkaloidy Vinca minor L. a jejich biologická aktivita II. / Vinca minor L. alkaloids and their biological activity II.

Pavuková, Simona January 2021 (has links)
Pavuková, S.:Vinca minor L. alkaloids and their biological activity II. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové 2020. Vinca minor L. is a species of species of flowering plant, native mainly to central and southern Europe, which containst more than 50 indole alkaloids. During screening of potential plant inhibitors against human acetylcholinesterase (hAChE) and butyrylcholinesterase (HBChE) at our department, an alkaloidal extract from dried aerial parts of Vinca minor demonstrated strong and selective hBChE inhibitory activity with an IC50 value of 13.60 ± 0.83 μg/mL, however, against hAChE was inactive (IC50 value >100 μg/mL). The fraction VM 323 - 327 (4,72 g) was separated by column chromatography on silica gel again with stepwise elution by using chloroform and ethanol and overall 7 joined fractions were obtained.Subsequently, repeated preparative TLC on silica gel led to isolation of three compounds; the newly isolated substance SP-1, (-)-picrinine (SP-2) and deacetylakuammiline (SP-3). Their structures were elucidated with mass spectrometry (ESI), NMR and optical rotation. Isolated alkaloids were tested on ability to inhibit AChE, BuChE, POP a GSK-3β, which are enzymes playing an important role in...
35

Příprava bioaktivních krytů ran a testování jejich interakce s lidskými buňkami / Preparation of bioactive wound dressings and testing their interaction with human cells

Bendová, Agáta January 2019 (has links)
The thesis was focused on the preparation and optimization of the preparation of wound dressing from materials with bioactive ingredients. In this work were prepared nanofiber dressings based on polyhydroxybutyrate and non-fibrous dressings from alginate and chitosan. Nanofibers were prepared by electrospinning and forcespinning methods. The bioactive components, which were used to functionalize the prepared dressings, were plant extracts, clotrimazole, ampicillin, lysozyme, and proteolytic enzymes. The theoretical part is focused on the description of the use of nanofibrous and non-fibrous materials in medicine, characterization of materials for the production of wound dressings and bioactive components. Furthermore, this section describes the methods used to prepare and characterize wound dressings. In the practical part were prepared aqueous and oil extracts from selected plants. Extracts were characterized for polyphenols content and antioxidant activity. PHB-based nanofibers were prepared using electrospinning and forcepinning methods. Nanofibers were enriched with selected plant oil extracts and clotrimazol. Modified nanofibres were detemined for antioxidant activity, short-term and long-term stability. Non-fibrous wound dressings were prepared from alginate and chitosan. These dressings were functionalized by the addition of selected aqueous extracts, ampicillin, lysozyme, papain, bromelain, and collagenase. Non-fibrous wound dressings were determined for antioxidant activity, short-term stability and proteolytic activity. The prepared wound dressings were tested for their antimicrobial effects on cultures of Micrococcus luteus, Serratia marcescens, Staphylococcus epidermidis and Escherichia coli. In conclusion, successfully prepared bioactive wound dressings with antioxidant and antimicrobial agents were tested for safety on human cells. The determination was performed using the MTT cytotoxicity test on human keratinocytes.
36

Struktura a vlastnosti kompozitů na bázi hydroxyapatitu a hořčíku, připravovaných metodou proudem asistované slinovací infiltrace / Structure and properties of Hydroxyapatite-Magnesium composites produced by the means of current assisted infiltration sintering

Casas Luna, Mariano January 2020 (has links)
Hořčík a kompozity fosforečnanu vápenatého jsou slibnými materiály pro biodegradabilní a nosné implantáty určené pro regeneraci kostí. Předložená práce je zaměřena na návrh, zpracování a charakterizaci vnitřně propojených kompozitů hořčíku s fosforečnanem vápenatým (Mg/CaP). Fosforečnany vápenaté jako jsou hydroxyapatit (HA), kalcium-deficitní hydroxyapatit (CDHA) a fosforečnan vápenatý (TCP) byly syntetizovány a použity pro výrobu skafoldů s kontrolovanou porozitou pomocí metody robocastingu. Byly připraveny porézní předlisky s ortogonální mřížkou a s vnitřními makropóry o velikosti ~500 µm, které byly následně slinovány za teploty 1100 °C po dobu 5 hodin. Vnitřně propojené Mg/CaP kompozity byly připraveny infiltrací čistého hořčíku a hořčíkových slitin obsahujících malá množství vápníku nebo zinku, například 0,2 hm.% vápníku a 1 hm.% zinku do porézních keramických skafoldů. Infiltrace byla provedena pomocí námi vyvinuté a nově popsané metody známé jako “Proudem asistovaná slinovací infiltrace” (z angl. Current Assisted Metal Infiltration (CAMI)). CAMI metoda umožňuje do 15 minut infiltrovat porézní keramický předlisek roztaveným kovem. Pulzujícím elektrickým proudem bylo dosaženo rychlého tavení a následného tuhnutí Mg/CaP kompozitů. Fyzikálně-chemické vlastnosti finálních vnitřně propojených kompozitů byly stanoveny pomocí rastrovací elektronové mikroskopie, počítačové mikro-tomografie, rentgenové difrakční analýzy a optické mikroskopie za účelem stanovení fázové distribuce a interakce mezi materiály. Kromě toho byla u připravených kompozitů hodnocena jejich mechanická pevnost v tlaku, degradační rychlost pomocí různých metod a biokompatibilita spolu s pokusem o uvedení těchto typů materiálů jako potenciálních degradabilních biomateriálů určených pro výrobu desek a/nebo šroubů pro ortopedické aplikace.
37

Příprava a charakterizace moderních krytů ran / Preparation and characterization of modern wound covers

Balášová, Patricie January 2021 (has links)
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.
38

Vlastnosti komplexů aminojílu a biologicky aktivních látek / Properties of aminoclay complexes and biologically active substances

Dušek, Jakub January 2020 (has links)
This paper builds on previous research of aminoclay complexes in undergraduate studies. Theoretical part deals with study of current problems of aminoclay complexes with bioactive substances and the choice of substances for complexing with aminoclay. The experimental part consists of preparation of aminoclay complexes with selected bioactive agents at various concentrations. Verification of binding of bioactive agents to the aminoclay matrix was performed by Elemental Analysis (EA) and Fourier-transform infrared spectroscopy (FT-IR). For finding of the bound amount of bioactive substance were used the Ultra Performance Liquid Chromatography (UPLC®) and analysis of the cytotoxic properties of the formed complexes by used by the MTT assay. The main motivation of this study is to create new complexes with improved characteristics that would replace existing forms of substances used in pharmaceutical and biomedical applications.
39

Přírodní látky v léčbě rakoviny a jejich cytotoxicita / Natural drugs in cancer treatment and their cytotoxicity

Hájková, Tereza January 2013 (has links)
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.
40

Mikrostimulátor / Microstimulator

Tobolová, Marie January 2012 (has links)
The theoretical part of the thesis deals with the explanation of the actions that occur during the stimulation of tissues with the electric current. A significant analogy with electrical circuits is used to describe the phenomena at the molecular and cellular level. The models of membrane and cell are necessary for understanding the behaviour of more complex structures, such as tissues and organs. A considerable attention is paid to the conditions of electrical stimulation which bring about response in the stimulated area. Next, the cumulative effect of the subthreshold stimulation is analysed. The mechanisms of common treatment effects of the electrotherapeutic methods are outlined. The research results in the practical part of the thesis – the design for a microstimulator. Properties of the microstimulator and compliance with standard requirements are verified by testing the electromagnetic compatibility and electrical safety, conducted by the Institute for testing and certification, JSC. The effects of microstimulation on living organisms are experimentally investigated on horses, in collaboration with the Veterinary and Pharmaceutical University. For the first time, thermodynamic sensors are used for the objective assessment of the microstimulation therapeutic effect. These miniature sensors are placed on the horse´s front legs and monitor the changes in thermal activity while only one limb is really stimulated and the other is just considered as a reference. Comparison and statistical evaluation of the measured signals could provide a more detailed view of the thermal changes within the stimulated area, which is significantly related to blood circulation in limbs, and with the support of the reduction of edema. The course of the experiment which deals with the effect of microstimulation on edema of the horse´s legs caused by minor injuries (tendinitis, sprains, etc.), is documented in photographs or videos that are significant for possible evaluation of the effectiveness of the stimulation in this application.

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