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Interactions of skin and stem cells with polymer nanofibres for construction of skin substitutes
Tomšů, Júlia ; Bačáková, Lucie (advisor) ; Sedmera, David (referee) ; Jendelová, Pavla (referee)
The skin is the largest organ of a human body with a crucial role in the maintenance of homeostasis; therefore any extensive skin injury leads to severe complications. Since the application of auto-, allo- and xeno-grafts is accompanied by severe problems like the source limitation and the graft rejection, a bioengineered skin substitute seems to be one of the promising healing approach. This work is focused mainly on the construction of a pre- vascularized skin substitute consisting of a collagen hydrogel reinforced by a biodegradable nanofibrous membrane. Another strategy described in this work is the development of temporary cellulose-based wound dressings. For both research strategies, various cell types were utilized, i.e. normal human dermal fibroblasts (NHDFs), human keratinocytes (hKs), adipose tissue-derived stem cells (ADSCs) and human umbilical vein endothelial cells (HUVECs). In order to enhance the cell adhesion and growth, the synthetic nanofibrous membranes were improved by protein nanocoatings. It was found out that NHDFs and ADSCs preferred fibrin nanocoatings, mainly thin fibrin homogeneous mesh on the surface of the membrane. Keratinocytes rather adhered and stratified on collagen substrates. These observations further motivated the construction of the bi-layered construct, where...
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Nanofibre medicated membranes 8.
Kučerová, Iveta ; Doležal, Pavel (advisor) ; Berka, Pavel (referee)
Thesis in theoretical part provides an overview of oral drugs in the biopharmaceutical point of view. It describes the main difficulties of this application route and presents selected facts about new approaches to improve the bioavailability of poorly absorbable substances. These approaches, in recent years, also use nanofiber membranes. The experimental part focuses on the in vitro evaluation of diamine delivery from nanofiber membranes in vehicle buffered at pH 7.4. The tested membranes contain the active substance in three graduated concentrations (20%, 30% and 40%), and specifically differ in basic weight. To evaluate the delivery the fluxes of diamine witin the first linear section of delivery are used, the percentage of substance released within 60 minutes was used to the evaluation of releasable proportion of diamine. Determination of diamine was performed by HPLC. The release of nearly all releasable diamine amounts were always obtained in 15 minutes from the beginning of release. The release rate of the diamine from nanofiber membranes is high. Important, however, is the finding that the rate of drug release is not probably significantly dependent on the drug concentration in the nanofiber membrane, but it is significantly influenced by the basic weight of membranes. The variability...
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Hydrophilically laminated nanomembranes
Urbanová, Martina ; Doležal, Pavel (advisor) ; Berka, Pavel (referee)
A theoretical part of the diploma thesis describes solubility, classification of solubility and ways of influencing of solubility, and it gives a detailed summary of naproxen as the drug further used and evaluated in in vitro experiments for drug release. An experimental section is focused to in vitro release of naproxen from nanofibre membranes produced by electrospinning with regard to the possibility of the use of layering. At both layered and non-layered nanofibre membranes of three different naproxen concentrations (e.g. 5%, 15% and 30% by weight) the drug release amounts within 5 minutes were from 10 to 90 percent of total amounts. An overal percentage of naproxen released in 60 minutes was always about 100 % of the total drug loaded in the nanomembranes. The nanofibre membranes layered with the glycerol and propylene glycol were of the same profiles as with non-layered membranes.
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Nanofibre medicated membranes 8.
Kučerová, Iveta ; Doležal, Pavel (advisor) ; Berka, Pavel (referee)
Thesis in theoretical part provides an overview of oral drugs in the biopharmaceutical point of view. It describes the main difficulties of this application route and presents selected facts about new approaches to improve the bioavailability of poorly absorbable substances. These approaches, in recent years, also use nanofiber membranes. The experimental part focuses on the in vitro evaluation of diamine delivery from nanofiber membranes in vehicle buffered at pH 7.4. The tested membranes contain the active substance in three graduated concentrations (20%, 30% and 40%), and specifically differ in basic weight. To evaluate the delivery the fluxes of diamine witin the first linear section of delivery are used, the percentage of substance released within 60 minutes was used to the evaluation of releasable proportion of diamine. Determination of diamine was performed by HPLC. The release of nearly all releasable diamine amounts were always obtained in 15 minutes from the beginning of release. The release rate of the diamine from nanofiber membranes is high. Important, however, is the finding that the rate of drug release is not probably significantly dependent on the drug concentration in the nanofiber membrane, but it is significantly influenced by the basic weight of membranes. The variability...
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