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Enhancing axon regeneration and neuroplasticity after spinal cord injury: Bridging the gap between development and disease
Štěpánková, Kateřina ; Machová Urdzíková, Lucia (advisor) ; Balaštík, Martin (referee) ; Rokyta, Richard (referee)
Enhancing axon regeneration and neuroplasticity after spinal cord injury: Bridging the gap between development and disease ABSTRACT The precise wiring of the adult mammalian central nervous system (CNS) is determined during axon growth, guidance and neuroplasticity during and shortly after development. This intricate system is unable to regenerate when the adult spinal cord is injured. It's not well understood how to translate what is known about developmental processes into therapies for spinal cord injury (SCI). Therefore, effective therapies are difficult to find. This thesis aims to fill an important gap in our understanding of how developmental strategies for axonal growth and plasticity are exploited in SCI regeneration. In particular, we will contrast two approaches: (i) reducing the inhibitory environment that forms around the lesion, and (ii) exploiting the inhibitory environment for regeneration by forcing the overexpression of an appropriate integrin isoform in sensory neurons and allowing axons to grow on this environment. In this thesis, Aim 1, we used 4- methylumbelliferone (4-MU) to reduce the inhibitory environment formed around the lesion. The first step was to assess the potential adverse effects of long-term treatment. Using immunohistochemistry, proteomics, biomechanics, qPCR,...
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Monitoring of mesenchymal stem cell migration in the extracellular matrix
Zumberg, Inna ; Čmiel, Vratislav (referee) ; Chmelíková, Larisa (advisor)
This master’s thesis contains a description of mesenchymal stem cells (MSC). The work includes knowledge about the process of migration and differentiation of MSCs. The theoretical part of this thesis also deals with the problem of cell cultivation in 2D and 3D environments. The most used materials for creating 3D scaffolds are described here. The practical part contains the description of the cell culture protocol for passaging and also describes the experiment in the cell laboratory. The results of the experiment are discussed using confocal microscope images. The proposed experiment was tested with a sufficient number of repetitions. The processing of microscopic images was performed in the MATLAB programming environment.
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Study of mesenchymal stem cell migration in the extracellular matrix based on principles of chemotaxis
Scholasterová, Viktorie ; Fohlerová, Zdenka (referee) ; Chmelíková, Larisa (advisor)
This thesis engages in a study of mesenchymal stem cell migration in extracellular matrix based on principles of chemotaxis. First, attention is focused on a theoretical part associated with a clarification of basic terms such as extracellular matrix, migration, confocal microscopy, mesenchymal stem cells or chemotaxis. There is also included a list and a description of some basic methods for monitoring cell migration and a more detailed description of a method called transwell assay, which has been chosen for an experiment in a practical part of this thesis. This part includes protocols of individual steps for the preparation of the experiment, the procedure of data processing obtained by scanning cells with a confocal microscope and a description of the resulting confluence values.
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3D models of brain tumors
Fišer, Ondřej ; Novák, Josef (advisor) ; Bohačiaková, Dáša (referee)
Despite intensive research, glioblastoma multiforme remains one of the tumours of the central nervous system with the worst prognosis. The ability of glioblastoma cells to infiltrate brain tissue by forming invasive microtubular structures is stimulated by contact with adjacent non- tumor cells. Intercellular communication and the influence of the extracellular matrix create a specific microenvironment that affects cell signaling, proliferation, differentiation and response to pharmaceuticals. The recurrent form of glioblastoma often displays a much faster progression than the initial disease, which is attributed to the development of resistance to therapeutics and the preservation of the proliferative capacity of some tumour cells. The discovery of the stem- cells ability to self-aggregate in suspension has led to the creation of 3D in vitro models - brain organoids. They are much more complex that the established 2D models and their heterogeneity provides an environment simulating the in vivo state. This thesis aims to describe their use in brain tumour research and techniques for culturing 3D aggregates of neural lineage formed from induced or embryonic human stem cells with respect to their gradually increasing complexity. It also presents methods of addressing issues of hypoxia, organoid...
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Proteomic analysis of engineered hyaline cartilage
Kaňovská, Zuzana ; Vičarová,, Petra (referee) ; doc. RNDr. Irena Koutná, Ph.D (advisor)
The aim of this thesis was to observe the expansion of chondrocytes, specialized cartilage cells, in vitro in culture medium containing platelet rich plasma, to evaluate the effect of the addition of growth factors TGF-1 and IGF-1 to the medium and to explore the possibility of proteomic analysis application in the development of cartilage joint replacements. Chondrocytes were isolated form articular hyaline cartilage samples acquired in collaboration with the FN Brno and expanded in media. The resulting constructs were subsequently analyzed by immunocytochemical method, flow cytometry and proteomic analysis using LC-MS/MS.
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Regeneration and structural changes of the nerve tissue after the extracellular matrix modification
Vallová, Jana ; Machová Urdzíková, Lucia (advisor) ; Hampl, Aleš (referee) ; Hubálek Kalbáčová, Marie (referee)
Regeneration and structural changes of the nerve tissue after the extracellular matrix modification. Abstract ECM modification may contribute to changes in nerve tissue plasticity. Therefore, 4- methylubulliferone is used in our study, which disrupted the structure of the perineuronal networks surrounding some types of neurons responsible for the formation of memory traces. Mice were fed a 4-MU diet (6.7 mg / g / day) for 6 months, which improved their memory skills in a spontaneous recognition test without a significant adverse effect on the kidneys, liver, or joints.In the next part of the study, an extracellular matrix (UC-ECM) was derived from fetal human umbilical cord tissue also generated as biomimetic hydrogel. Due to the generated UC-ECM's low stability and rapid degradation, the structure was stabilized by covalent genipin bonding. Stabilization with 1 mM genipine increased the biological stability of the material. UC-ECM as well as ECM/G didn't show toxicity in vitro in mesenchymal stem cell proliferation; axonal budding or neural stem cell growth and differentiation were not adversely affected. The biocompatibility of both materials was verified in vivo by applying the material to an intracortical photothrombotic rat lesion, where gelation and infiltration of the lesion and hydrogel by host...
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Studies of intercellular interactions in tumours
Jechová, Alžběta ; Smetana, Karel (advisor) ; Skalníková, Helena (referee) ; Masařík, Michal (referee)
Beside tumor cells themselves, tumors consist of many non-malignantly transformed cellular elements and an extracellular matrix. This so-called tumor microenvironment, or stroma, significantly influences the biological properties of the tumor through intercellular interactions. In this thesis I have focused on the study of tumor-associated fibroblasts in squamous cell carcinomas of the head and neck, malignant melanoma and glioblastoma. The data show the presence of cells with mesenchymal characteristics, present even in the glioblastoma stroma, which could potentially have a positive effect on proliferative activity and invasiveness of glioblastoma cells. In malignant melanoma, the presence of keratinocytes should also be considered, as they are the major cells of the epidermis influencing tumor melanocytes. The conditioned medium from UVB irradiated keratinocytes and non-irradiated fibroblasts stimulates the invasion of malignant melanoma cells. Targeting the tumor stroma may be a new direction in oncological therapy, so we have focused on the influence of synthetic polyamine on the formation of myofibroblasts, which are an active part of the population of tumor-associated fibroblasts. The tested polyamine prevents the formation of myofibroblasts but has no effect on those already formed nor on...
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Matching the role of chondroitin sulphate proteoglycan, aggrecan, in dense extracellular matrix of perineuronal nets and glial scar
Gmiterková, Lenka ; Růžička, Jiří (advisor) ; Telenský, Petr (referee)
Traumatic brain and spinal cord injuries are worldwide medical problems. Disruption of the tissue leads to the changes in the cellular and extracellular matrix composition. This newly formed scar is not permissive for the axonal regrowth. Its function in prohibiting neuronal plasticity is similar to the perineuronal nets present in undamaged brain. One of the key components of both perineuronal nets and scar is proteoglycan aggrecan. In this thesis I focused on the function of aggrecan in central nervous system, mechanism of its growth inhibitory feature and research in the field of traumatic brain or spine cord injury treatment. It is important topic, since currently there are not any approved human therapies to recover axonal growth at the site of formed scar.
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The role of ageing in the changes of the brain extracellular matrix and extracellular space properties
Kamenická, Monika ; Vargová, Lýdia (advisor) ; Růžička, Jiří (referee)
The process of aging causes the major changes in nervous tissue such as changes in the size of brain, architecture of glial cells and extracellular matrix. The size of brain is on the decrease as consequence of aging and there is a change of molecules as well as morphology at all levels. Extracellular space (ECS) is interstitium important especially in communication between cells mediated by diffusion. The limit of diffusion in extracellular space is given by size of ECS, which is discribed by volume fraction and tortuosity, that reflect amount of diffusion barriers. The changes of ECS diffusion parameters during aging were measured by real-time iontophoretic method in four parts of brain (cortex - Cx, hippocampus - Hp, inferior colliculus - IC and corpus trapezoideum - TB). Further, we studied influence of deficiency of Bral2 link protein at differences of ECS diffusion parameters and importance of Bral2 protein at aging and regulation mechanisms of cytotoxic brain edema. Our results show, that aging leads to decreasing of ECS volume v Cx and Hp, but it was not observed in IC and TB, where the intact perineuronal nets act like protecting shield against the degenerative disease induced by aging. However, small differences in composition of perineuronal nets, deficiency of Bral2 link protein, may...
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Extracellular matrix in yeast populations
Novotná, Pavla ; Kuthan, Martin (advisor) ; Dvořáček, Lukáš (referee)
The microorganisms in a natural environment are frequently found in multicellular forms, most commonly in biofilms. Biofilm is characterized as a community of cells living at the interface of two environments, embedded in the extracellular matrix. ECM is a significant component of biofilms in yeast populations. Extracellular matrix acts as a protective barrier and allows cells to survive under adverse conditions and better compete with other microorganisms. It also forms an effective barrier against antibiotics and other harmful substances, what makes biofilms a serious problem in medicine and industry. Formation of the matrix may be influenced by the morphological forms of colonies. Increased formation of ECM is commonly connected in phenotypic switching in response to changes of their living conditions. The compositeion of the ECM is a genus-and species-specific. The main component of the matrix consists of polysaccharides and proteins.
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