National Repository of Grey Literature 25 records found  beginprevious16 - 25  jump to record: Search took 0.00 seconds. 
Detection and visualization of native and artificial chondrogenous tissue using biophysical methods
Rampichová, Michala ; Amler, Evžen (advisor) ; Rosina, Jozef (referee) ; Kolářová, Hana (referee)
Tissue engineering is a rapidly developing field, based on using scaffolds made from natural or synthetic materials in combination with cells and stimulating factors for the replacement of damaged or lost tissue. It is very important to evaluate qualities of these scaffolds, which are necessary for cell proliferation and their mechanical support. The aim of this study was to develop a suitable scaffold for chondrocyte proliferation, scaffold functionalization and detection of cells and proteins of extracellular matrix (ECM) using methods of fluorescence and confocal microscopy. Another aim was to test an appropriate scaffold on a big animal model in vivo. Several scaffolds from natural and synthetic materials, in the form of microfibers, non-woven textiles, gels and foams were prepared for this study. Scaffolds were seeded with chondrocytes and cell adhesion, proliferation and synthesis of ECM proteins were detected. Methods of fluorescence microscopy, confocal microscopy and second harmonic generation (SHG) were used for visualization of cells and proteins. A hydrogel based on fibrin and hyaluronan was used as an scaffold for osteochondral defect regeneration in minipigs study. Prepared scaffolds showed high biocompatibility, good chondrocyte adhesion and ECM proteins synthesis. Moreover, microfibrous...
Identification of changes in mechanical characteristics of human axial system as a result of loading and relaxation regime
Van der Kamp Kloučková, Kateřina ; Jelen, Karel (advisor) ; Maršík, František (referee) ; Rosina, Jozef (referee)
Problem: A lot of attention is given to the safety of the driving and the possibility to register fatigue of the drivers. Driving cars is monotony and static. Vibration loading, which causes changes in the axial system. This causes discomfort and fatigue to drivers after some time of exposure to the loading. Hypothesis: It is possible to prove the changes of mechanical characteristics (indicators) of the axial system using the TVS (transfer vibration through spine) method. By using TVS method before and after different types of loading or before and after relaxation it is possible to detect changes of the viscoelastic properties. This can be done by checking changes in the way of waves transfer through the axial system of the observed participants. Objective: Verify the possibility of use of TVS method to register changes of the viscoelastic characteristics of the axial system. Method: The TVS was chosen as a detection method. The method is based on the use of five-msec semi-bandwidth γ pulse stimuli and consequent application of continuously changing harmonic stimuli which periodically differ between 5Hz and 160Hz to the vertebrae C7 and L5. This wave is carried through the axial system and its acceleration on the spinous processes between C7 and S1 is scanned with the help of accelerometric...
Characterization of functionalized fibres for mesenchymal stem cells cultivation and differentiation
Greplová, Jarmila ; Amler, Evžen (advisor) ; Rosina, Jozef (referee)
Modification of nanofibers is an actual trend in tissue engineering. Polyvinylacohol (PVA) is nontoxic and biodegradable polymer suitable for preparation of submicron fibers by electrospinning. Main disadvantage of PVA fibers is rapid degradation in aqueous environment. On the other hand surface of fibers contains free hydroxyl group that could be chemically modified. In recent work, chemical modification of PVA nanofibers prepared by needleless electrospinning was investigated. Polyethylenglykol (PEG) linker was introduced to the fiber surface by acylation (PVA-PEG) and further modified by biotin (PVA-PEG-b) as a function agent. Process of chemical modification does not affected fibrous morphology of samples. Interestingly, linkage of PEG-b linker promoted stability of PVA in aqueous environment. PVA-PEG-b sample was stable for 41 days. Stability of samples was strongly dependent on amount of introduced PEG-b linker, thus proposed method of modification allows to prepare nanofibers of different solubility. Additionally, biocompatibility of chemically modified nanofibers with both mesenchymal stem cells (MSC) and chondrocytes was determined. Proliferation of both cell types was not sufficient and number of cells decreased in time, probably because of high hydrophility of modified PVA scaffold. To...
Physical factors influencing the development of corneal damage by UV rays
Čejka, Čestmír ; Rosina, Jozef (advisor) ; Štípek, Stanislav (referee) ; Amler, Evžen (referee) ; Salminen, Lotta (referee)
Purpose: The purpose of the Thesis "Physical factors influencing the development of corneal damage by UV rays" was a) to determine the light absorption properties in the rabbit cornea irradiated with UVB rays by measuring of physical values of absorbance A and transmittance T as functions of wavelength ; b) To investigate the absorption coefficient as a function of wavelength ; c) To evaluate the importance of this coefficient for corneal light absorption properties; d) To determine the light absorption properties in the rabbit cornea irradiated with UVA by measuring of physical values of absorbance A and transmittance T as functions of wavelength (to compare the effect of UVA with UVB rays). Material and Methods: To achieve individual aims, the new spectrohotometrical method was developed and following experimets were performed: a) Repeted irradiation of the rabbit cornea with UVB rays (daily dose 1.01 J/cm2 during 5 days); b) Repeated irradiation of the rabbit cornea with UVA rays (daily dose 1.01 J/cm2 or 2.02 J/cm2) during five days; c) Repeated irradiation of the rabbit cornea with the daily dose of 1.01 J/cm2 during 4 days and in individual time intervals investigation of corneal light absorption and hydration changes; d) The anti-UV efficacy of UV filter (actinoquinol combined with hyaluronic acid,...
Risk factors for malignant neoplasms of skin and prevention options
Rosina, Jozef ; Čelko, Alexander (advisor) ; Kolářová, Hana (referee) ; Dohnal, Karel (referee) ; Navrátil, Leoš (referee)
Skin tumors are the most common types of tumors in humans. Their incidence is steadily increasing. Increases and mortality, especially in malignant melanoma. Risk factors playing an important role in the development of skin cancer, solar radiation belong. UV spectrum of sunlight is the most important cause of skin cancer. Therefore, the degradation of the ozone layer and the associated increased levels of UV radiation reaching the world so much studied. Among other known risk factors belong phenotype of human acute intermittent sunburn, especially in children and adolescents, increased tendency to form freckles skin after exposure to sunlight and the presence of pigmented nevi. Some people may find a genetic basis. The risk of malignant melanoma is also rising in people who have a history had already been diagnosed with this disease. Significant for the possibility of skin malignancy is immunosuppression. The work is focused on statistical analysis of most of the above mentioned risk factors.
název v anglickém jazyce není uveden
Fikáčková, Hana ; Navrátil, Leoš (advisor) ; Dostálová, Taťjána (referee) ; Rosina, Jozef (referee)
Temporomandibular joint disorders (TMD) are defined as a collective term embracing clinical problems that involve the masticatory musculature, the temporomandibular joint and associate stuctures. These disorders are primarily characterized by pain, joint sounds, and irregular or limited function. Other common complaints are headache, jaw-ache, ear-ache, facial pain or tinnitus [Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen zdroj odkazů.]. Carlsson [Chyba! Nenalezen zdroj odkazů.] reported in a review of the epidemiologic literature that the need for treatment of TMD is with a range 5% and 13% among adults. At present, the majority of authors propose a multifactor aetiology for TMD, considering that acute trauma, degenerative articular disorders, psychological factors and functional mandibular overload are involved [Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen zdroj odkazů.]. Although the diagnosis of TMD is based mainly on the detailed patient's history and clinical examination, in some cases it is necessary to complete these routine procedures through imaging methods that can help to find out the cause of a patient's pain [Chyba! Nenalezen zdroj odkazů.,Chyba! Nenalezen...
Pyrimidine metabolism in the environment of post-radiation chemotherapy response - a model for determining the optimal scheme chemoradiotherapy
Vítek, Pavel ; Rosina, Jozef (advisor) ; Zámečník, Jiří (referee) ; Petera, Jiří (referee)
Objectives of thesis research: 1.2 Primary objectives - Identify part-time post-radiation reactions, respectively. determine the dynamics of induction of expression of certain genes involved in its product in the metabolism of fluorinated pyrimidine. - Identify relevant increases in respective protein. - Some developments TP / DPD ratio. 2.2 Secondary objectives - Verify the model fluorinated pyrimidine potentiation of radiation as a basis for supraaditivní chemoradiaci in effect. - Determine the optimal scheme for the application of fluorinated pyrimidine in fractionated radiation application.
Immunomodulation effects of the hyperthermia in cancer treatment
Kubeš, Jiří ; Rosina, Jozef (advisor) ; Vrba, Jan (referee) ; Zámečník, Jiří (referee)
The dissertation thesis "Immunomodulation effects of the hyperthermia in cancer treatment" relates on the hyperthermia as evolving method of the cancer treatment. The first part describes hyperthermia in general, especially physical principles of the heating, the equipment necessary for clinical practice of the hyperthermia, basic effects in biological tissues, clinical indications and results. The second part is brief review of mechanisms antitumor immunological response, with emphasis on antigenicity of tumor cells and effector cells in antitumor response.
Enhanced biomechanical characteristics of connective tissues and development of artificial implants
Varga, Ferdinand ; Amler, Evžen (advisor) ; Rosina, Jozef (referee) ; Daniel, Matej (referee) ; Sabo, Ján (referee)
(english) Hyaline cartilages are designed to enable smooth life-long articular move- ment. They serve also substantial role in load bearing, being loaded especially in normal compression. Eventual deterioration of articular cartilage tissue therefore has crucial consequences for affected individ- ual. Characterization of native articular cartilage and application of gained knowledge in reconstructive cartilage treatment is therefore de- sired. Mechanical characteristics are of prime importance. Blunt impact testing method in pendulum setup was developed to characterize cartilage tissue under physiological values of dynamic com- pressive loading. Information on impact process was simultaneously read by piezoelectric accelerometer and laser doppler vibrometer. Acquired data were processed to form loading diagrams and to evaluate standard mechanical quantities. The method was found to be consistent, reliable and effective way of mechanical characterization. Introduced technique was used for qualitative and quantitative de- scription of native articular cartilage, correlation of its condition with mechanical properties, assessment of tissue engineered materials quality and approval of newly designed artificial materials suitability. Consider- ing native cartilage status, dissipated energy was found to be...
The influence of magnetic field of power frequency on the adherence of leukocytes in patients with head and neck cancer
Čoček, Aleš ; Filip, Stanislav (advisor) ; Rosina, Jozef (referee) ; Vávrová, Jiřina (referee)
We know from research conducted to date that magnetic field of low-induction power frequency (50 Hz) increases the in vitro adherence capacity of T lymphocytes in patients with squamous cell larynx/pharynx cancer as well as that of T lymphocytes of voluntary blood donors (control group), towards the surface. The objective of this thesis was to find out if there is a difference between the impacts of low induction values, and to confirm or disconfirm the literary assumption that lower induction values have more pronounced influence on biological systems. At first, we carried out comparative tests of T lymphocyte adherence inhibition in the absence of magnetic field and in the presence of a field with a single set induction value (10mT (n=30), 1 mT ( n=30), 0.5 mT ( n=76), 0.1 mT (n=60), 0.05mT (n=69)). Blood samples from 265 patients were investigated in this way. The control group consisted of T lymphocytes of voluntary blood donors (n=316). As the next stage, T lymphocyte inhibition adherence tests were simultaneously carried out without the presence of magnetic field and with the presence of a field of comparable inductions so as to compare the T lymphocyte ability of one and the same patient (i.e. comparing the adherence capacity without field with that in the presence of a field of 0.1 mT, 0.05...

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