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Monitoring The Parameters Of Cells Migrating In Pseudo-3d Extracellular Matrix
Zumberg, Inna
Cell migration plays an essential role in a number of biological processes, such as embryogenesis,the immune response, wound healing and inflammation. Most research regarding cellmigration is based on experiments using two-dimensional (2D) cell cultures, and the detailed molecularand biophysical mechanisms of these processes are already well known. However, muchless is known about cell behaviour in the three-dimensional (3D) environment of living tissues.Pseudo-three-dimensional (pseudo-3D) cell cultures bridge the gap between 2D and 3D geometriesand combine their advantages. This review presents the quantitative evaluation of human mesenchymalstem cells (hMSCs) migration parameters in pseudo-3D artificial extracellular matrix(ECM) of various compositions.
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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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Use of biological materials for tissue substitution in plastic surgery
Měšťák, Ondřej ; Sukop, Andrej (advisor) ; Brychta, Pavel (referee) ; Dražan, Luboš (referee)
Užití biologických materiálů k náhradě tkání v plastické chirurgii ! Abstrakt v angličtině Background: Biological meshes are biomaterials consisted of extracellular matrix and used in surgery particularly for hernia treatment or thoracic wall reconstruction. They are capable of vascularization, that decreases risk of infection, expecially when used in contaminated fields. This study compared the strength of incorporation and biocompatibility of two porcine-derived grafts (cross-linked and non-cross-linked) in a rat hernia model. In addition, we hypothesized that combination of extracellular matrices with autologous mesenchymal stem cells used for hernia repair would result in increased vascularization and increased strength of incorporation. Methods: Standardized 2 x 4 cm fascial defect was created in 42 Wistar rats and repaired with a cross-linked or a non-cross-linked graft either enriched or non-enriched with stem cells. The rats were sacrificed 3, 6 and 12 months later. The strength of incorporation, vascularization, cellular invasion, foreign body reaction and capsule formation were evaluated. Results: Comparison of stem cell enriched and non-enriched groups showed no significant differences in the capsule thickness, foreign body reaction, cellularization or vascularization. In the non-cross-linked...
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Cell and Molecular Characterization of Failed Human Corneal Grafts. The Role of Matrix Metalloproteinases in Recurrent Corneal Melting.
Brejchová, Kristýna ; Jirsová, Kateřina (advisor) ; Smetana, Karel (referee) ; Heissigerová, Jarmila (referee)
The aim of this work was to investigate the contribution of matrix metalloproteinases (MMPs) to recurrent corneal melting. Twenty three melted corneas from seven patients were separated into three groups: a) patients with primary Sjögren's syndrome, b) those with rheumatoid arthritis and c) those with other corneal melting underlying pathologies. Eleven cadaverous corneas served as controls. The presence of MMP-1, -2, -3, -7, -8, -9, and -13 was detected using indirect enzyme immunohistochemistry. The active forms of MMP-2 and -9 and MMP- 3 and -7 were examined by gelatin and casein zymography, respectively. The concentrations of active MMP-1 and -3 were measured using activity assays. Increased immunostaining intensity for MMP-1, -2, -3, -7, -8 and -9 was shown in the corneal epithelium and the stroma of almost all melted corneas from all three groups compared to the negative or slightly positive staining of the controls. In the endothelium, immunostaining for MMP-2 and MMP-9 was increased in most specimens of groups II and III and group I, respectively. A markedly higher level of active MMP-2 was detected in six, and active MMP-9 in all, pathologic specimens compared to the controls. In contrast to the completely negative controls, the proenzymes of MMP-3 and -7 were detected in almost all melted...
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Development of extracellular-matrix scaffolds for CNS repair
Výborný, Karel ; Kubinová, Šárka (advisor) ; Hampl, Aleš (referee) ; Vandrovcová, Marta (referee)
Výborný, Karel. Vývoj materiálů na bázi extracelulární matrix pro léčbu centrálního nervového systému. [Development of extracellular-matrix scaffolds for CNS repair]. Praha, 2020. 105 stran, 3 přílohy. Dizertační práce (Ph.D.). Univerzita Karlova, 2. lékařská fakulta, Ústav experimentální medicíny, AV ČR v.v.i. Abstract Brain and spinal cord injury are a serious traumata and despite intensive research, there is still no effective treatment for patients. One of the studied approaches is to use various biomaterials to repair the damaged neural tissue. The aim of this thesis is to study the regenerative and neurotrophic effects of injectable extracellular matrix (ECM) hydrogels prepared by decellularization from porcine tissue (brain, spinal cord, bladder) and human umbilical cord (UC) in reconstruction of damaged neural tissue of the brain and spinal cord in rats. We characterized ECM hydrogels in terms of mechanical and rheological properties, structure and composition, cell adhesion, migration and proliferation. In a model of spinal cord hemisection, we compared the regenerative effect of ECM hydrogels derived from porcine spinal cord and urinary bladder. We found no benefits of tissue specific ECM prepared from the tissue of neural origin in terms of its neurotrophic properties in vitro or in vivo....
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Natural biomaterials and mesenchymal stem cells in regeneration of spinal cord injury
Kekulová, Kristýna ; Kubinová, Šárka (advisor) ; Krulová, Magdaléna (referee) ; Filová, Elena (referee)
Spinal cord injury is a serious trauma and despite intensive research there is still no effective treatment for patients. The aim of this thesis is to study new possibilities of spinal cord injury therapy in animal models. We have focused on the use of natural materials, stem cells, gene therapy and the possibility of combining these approaches. The effect of extracellular matrix (ECM) based materials prepared by decellularization of porcine spinal cord and porcine urinary bladder on tissue regeneration after acute hemisection of the spinal cord was investigated. Another tested material was a hydrogel based on hyaluronic acid modified with RGD adhesion peptide, which was applied acutely and subacutely into the hemisection lesion. We have shown that both types of biomaterials have positive effect on regeneration of the spinal cord tissue by bridging the lesion and promotion of axonal ingrowth. In addition, ECM hydrogels promote the growth of blood vessels into the lesion site. The combination of hydrogels with mesenchymal stem cells derived from human umbilical cord (hWJ-MSCs) had synergistic effect, but since only a limited number of cells could be incorporated into hydrogels, this effect was not associated with improvement in motor skills. The limitation of ECM hydrogels is their rapid...
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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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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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Role of sulfhydryl oxidase 1 in cancerogenesis
Beranová, Lea Marie ; Truksa, Jaroslav (advisor) ; Šuťák, Róbert (referee)
Disulfide bridges play a significant role in protein-folding as well as en- zyme activity and thus regulate many intra- and extracellular processes. Sulfhydryl oxidase QSOX1 forms S-S bridges de novo, modulating the activity of its substrates and thus directly or indirectly influences vital cel- lular processes. The first part of this thesis focuses on characterization of the role of QSOX1 in cancerogenesis, using breast cancer cell lines (MCF7, MDA-MB-231) and pancreatic cancer cell line (Panc-1), while the second part emphasizes the regulation of QSOX1 expression by different oxygen concentrations. To study the effect of QSOX1 on proliferation of triple-negative cancer cells MDA-MB-231, two genetically modified cell lines - QSOX1-overexpressing and QSOX1 knockout cell lines - were constructed. While increased QSOX1 protein levels do not have a significant effect, the absence of QSOX1 leads to a decreased cellular growth. Lack of QSOX1 also results in visible change in cellular morphology. QSOX1 knockout cells can be mostly characterized as more round-shaped with less noticeable or completely missing lamellipo- dia. This finding is with agreement with to-date literature suggesting that QSOX1 is important not only for cellular proliferation but also for migration and invasiveness. While authenticating the theory of...
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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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