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Prenatal limb development and its pathology
Skoupá, Veronika ; Hovořáková, Mária (advisor) ; Zahradníček, Oldřich (referee)
Limb defects are the second most common congenital disease in children. They occur in the prenatal period and are most often caused by genetic defects or chromosomal abnormalities. Limb defects can also be caused by the action of various teratogens, which can disrupt the development of the fetus. The prenatal development of a child is an extremely complicated sequence of a large number of interconnected events, which, despite considerable advances and discoveries in the field of molecular biology over the last few decades, we still do not fully understand. The present thesis tries to summarize the problem of limb defects from their origin, through possible causes to several diseases that are associated with limb anomalies. Improvement of our knowledge in the field of limb development and defects associated with it is important for accurate prenatal diagnosis and subsequent successful treatment of patients.
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Testing of embryotoxicity of selected human teratogenes on chicken embryos.
Pavlíková, Zuzana ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
Teratogenes are external environmental factors that can cause a developmental or a congenital defect in exposed individuals. The methods used for detecting the embryotoxic effect of substances are the classic when laboratory mammals are used and the alternative which use in vitro and in ovo systems. The main difference between these two is that the alternative methods lack metabolism of maternal organism. The metabolism of maternal organism brings a high variability of results to systems of the classic methods. We used two alternative methods in this thesis, both using chicken embryo. The first of them was in ovo method called CHEST (Jelínek, 1977). CHEST method can be used for administration of tested substances from ED2 to ED6. The disadvantage of this method is due to the dilution of the tested substance after subgerminal application at ED2. Therefore we developed in vitro method called SANDWICH. No dilution occurs while using the SANDWICH method. The aim of this study was to develop in vitro method SANDWICH while using proven teratogene (all-trans retinoic acid) and its solvent (dimethyl sulfoxide), to estimate beginning of the embryotoxicity dose range for both substances using CHEST and SANDWICH, and finally to compare obtained results. We confirmed the embryotoxic effect of all-trans...
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