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New modified method of neonatal cleft lip surgery
Borský, Jiří ; Peterka, Miroslav (advisor) ; Jirásek, Jan Evangelista (referee) ; Měšťák, Jan (referee)
2 2. Abstract Cleft palate is one of the most frequent congenital malformations. The complexity of these conditions requires surgical treatment in several stages. The first stage includes reconstruction of the nose and the lip, and timing is either shortly after birth, or, in about two thirds of centers worldwide this surgery is performed at the age of 3 months. The next stage, palate defect repair, is timed at around 9 months of age, and the final reconstruction of the maxilla is done based on the permanent canine eruption at about 8 years of age. The main objective of our study was to estimate the pros and cons of early surgical approach after introducing a novel modified surgical protocol versus the conventional surgical protocol. The 5 main findings include: 1. A novel surgical procedure to repair neonatal cleft lip was developed, incorporating modification of Tennison protocol by adding flaps acquired from the margins of the cleft. An important contribution is a shorter time both under anesthesia and in the theatre, and resulting reduction of hospital stay from 7-8 days down to 3-4 days. 2. We have compared the biochemical parameters of the surgical wound healing - matrix metaloproteases (MMP) and their inhibitors (TIMP) in the group of children having surgery early in neonatal age and in children...
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Embryotoxicity test of insulin-glucose interaction
Vobrová, Renata ; Peterka, Miroslav (advisor) ; Peterková, Renata (referee)
Diabetes mellitus is heterogeneous group of diseases. Their common characteristic is failure of metabolism carbohydrate, fats and proteins which is caused by an absolute or relative lack of insulin. A lack of insulin leads to the hyperglycemia. If diabetes is present, glucose and insulin, which physiologically occur in a body, are not in a balance. Pregnant women with diabetes have 7x - 10x higher risk of incidence offspring congenital malformations and there is also 2x - 5x higher risk of neonatal death compared to a population of healthy women. There have been disputes whether the teratogenic potential should be attributed to insulin, glucose, or whether the teratogenic effect of these substances increases through interaction. There is a question how much can maternal organism with diabetes disorder participate to the formation of congenital defects. The embryotoxic effects of insulin itself is not possible to study in the experiment on mammals, because it is not possible to distinguish the effect of the substance itself from the effects of disturbed metabolism of the maternal organism. The unique opportunity is to test the chicken embryo that develops outside the maternal organism. Therefore, we choose the aim of this thesis a test method CHEST (single application 2nd - 5th embryonal day) and a...
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Embryotoxicity test of thyroxine on chick embryo.
Petrušková, Michaela ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
Thyroxine is the main thyroid gland's hormone. The state, when the thyroid gland does not produce enough of it into the bloodstream is called hypothyroidism. Hypothyroidism is related with several health complications; therefore it is required to take replacement therapy in adequate doses. Concerning pregnant women, it is important especially to keep the blood level of thyroxine in the normal, because increasing or decreasing of it, has an adverse effect on the health of the mother and also on the normal child development. The objective of my thesis was to describe malformations spectra of thyroxine, to find out the beginning of its embryotoxicity dose range for chick embryos, and recalculate this value for human embryos, allowing us to decide, if the level of thyroxine was increased by a replacement therapy, this could be embryotoxic for human. The experimental part of my work was to search an alternative method for testing embryotoxicity on chick embryos in ovo - CHEST, testing of embryotoxic potential of the thyroxine. Embryotoxicity is a feature of the external factors affecting the embryo, it may manifest as lethality, growth retardation, and teratogenicity; which is an ability of the external factor to induce the developmental defect. The most common manifestation of embryotoxicity in this...
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Effect of addictive drugs on prenatal development
Hofmannová, Oldřiška ; Peterka, Miroslav (advisor) ; Peterková, Renata (referee)
Substance abuse is long-term worldwide problem. This thesis summarizes findings about the effects of stimulants, opiates and hallucinogens and focuses on the most commonly used illegal representatives of individual groups: cocaine, amphetamines, heroin and LSD. All these substances have negative effect on both mother and her fetus. Some of addictive substances can influence pregnancy and childbirth. There is also higher risk of fetus mortality and morbidity of the new born baby. Prenatal exposure to addictive substances could have influence on the birth weight, length, head circumference, its further growth and behavior. Some drugs can cause neonatal abstinent syndrome which can lead without prenatal care to death of newborn.
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The comparation of embryotoxical effect of insulin and glucose by the method CHEST.
Turková, Aneta ; Peterka, Miroslav (advisor) ; Likovský, Zbyněk (referee)
If gravid women suffer from diabetes,their unborn children have 10x higher risk of development of malformation,prenatal and postnatal death and post partum complications than children of women belonging to healthy population.The main and very controversial potential teratogenic factors are glucose and insulin.However,there are very ambivalent opinions on which one of these two substances causes damage to embryo. Therefore,the aim of this diploma thesis was to contribute to solving of this problem and test direct embryotoxicity of insulin and glucose. For solving of this issue, the so-called CHEST.The principle of this method is creation of a window in eggshell and consequent subgerminal or intraamnial application of the substance being tested.Embryos were tested from the second until the sixth incubation day.Firstly, two types of insulin were injected.Injected doses varied between 3µg/3µl to 0,003µg/3µl. Then glucose was tested,with dosage of 300µg/3µl and 30µg/3µl. Embryotoxic effect was detected for both types of insulin. The beginning of embryotoxicity line of insulin's lies between the dosage of 0,03µg/3µl and 0,003µg/3µl. From embryotoxic effect, death of embryos predominated over development of congenital malformations. Only after application on the second incubation day, there was increased...
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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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Formation of human dental anomalies in odontogenesis of mouse models with gene defects.
Lochovská, Kateřina ; Hovořáková, Mária (advisor) ; Peterka, Miroslav (referee)
Laboratory mouse is a appropriate experimental model for studies on normal tooth development mechanisms and for understanding of etio-pathogenesis of dental anomalies in humans. Mouse dentition consists of one incisor separated from three molars by toothless diastema in each jaw quadrant. Although an adult mice diastema does not contain teeth, rudimentary tooth primordia (MS, R2) appear here during embryonic development. However, their development stops and consequently functional tooth does not arise here. It is known that in mice with mutations in Spry2 and Spry4 genes, supernumerary teeth arise in antemolar region. The understanding of the temporo-spatial dynamics of signaling centers in Spry2/Spry4 double transgenic mice may help to elucidate the role of these embryonic diastemal buds in supernumerary tooth formation. The research of possible regeneration of dental anomalies in off-spring of crossing Spry4 deficient mice with supernumerary teeth formation with Eda deficient mice with predisposition to reduced dentition could be the way to elucidating of mechanism of dental pathologies development in general. Our aim was to describe temporal and spatial dynamics of Shh signaling domains in Spry2/Spry4 embryos, because Shh is one of the markers of early odontogenesis and determining of...
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Analysis of embryotoxic effect of hydrocortisone using chick embryotoxicity screening test (CHEST).
Janíková, Michaela ; Peterka, Miroslav (advisor) ; Hovořáková, Mária (referee)
Cleft lip is one of the most common human birth deffects. Its etiopathogenesis is multifactorial and many aspects of its occurrence remain unknown in the fields of both genetics and teratology. One of the set of known negative external factors causing cleft lip is chemical hydrocortisone. Its effect on cell proliferation is highly heterogeneous and depends on attributes of a specific cell population. In this work we studied the cleft beak origin after the hydrocortisone treatment on the basis of Chick Embryotoxicity Screening Test (CHEST). Our main aim was to detect cell cycle changes in the chick frontonasal process after hydrocortisone injection via flow cytometry analysis. Hydrocortisone caused S phase arrest within a minor subpopulation of highly granular cells with specific cell cycle. This sensitive subpopulation was localized in the areas of previously defined proliferative centers within the frontonasal process using immunohistochemistry of frozen sections. Quantitative analysis of cells in these areas revealed significant decrease of M phase portion in the hydrocortisone treated samples in comparison with the control samples. The TUNEL staining of histological sections was used to determine the apoptotic rate in the frontonasal process. The comparison between the control and the...
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The role of Wnt signaling in embryonic development.
Dupačová, Naoko ; Kozmík, Zbyněk (advisor) ; Peterka, Miroslav (referee) ; Pavlínková, Gabriela (referee)
Ph.D. thesis: The role of Wnt signaling in embryonic development Naoko Dupačová (Fujimura) ABSTRACT Wnt signaling plays important roles in multiple developmental processes. The binding of Wnt ligands to their receptors and coreceptors activates three main downstream pathways: canonical Wnt/β-catenin signaling, which results in the activation of β-catenin/Tcf mediated gene expression and noncanonical Wnt/PCP and Wnt/Ca2+ pathways. In this thesis, we aimed at studying the role of Wnt/β-catenin signaling during embryonic development, especially in the telencephalon and the eye. Wnt/β-catenin signaling is essential for the maintenance of proliferation of neuronal progenitor cells and dorso-ventral specification during the telencephalon development. To provide further insights, we studied transcriptional targets of canonical Wnt signaling. We show that the ectopic activation of Wnt/β-catenin signaling results in the up-regulation of Sp5 gene, which encodes a member of the Sp1 transcription factor family. A proximal promoter of Sp5 gene contains five Tcf/Lef binding sites that mediate direct regulation of Sp5 expression by canonical Wnt signaling. We further provide evidence that Sp5 works as a transcriptional repressor. Finally, our data strongly suggest that Sp5 has the same DNA binding specificity as Sp1 and...
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The problem of infertility and the methods of resolving..
Semyakina, Anastasiya ; Peterka, Miroslav (advisor) ; Novotná, Božena (referee)
4 Abstract This diploma thesis is concerned with modern methods of treatment for infertility. It examines to what extent and in what cases are these methods used and what risk does it pose for a woman's and a child's health. Paticular emphasis is placed on the methods of assisted reproductive technology as the most used, effective and the most invasive. Nowadays 10-15% of couples face the problem of infertility. In most of the cases this problem can be solved with the help of hormonal therapy, surgery or assisted reproductive technology. The most common complication of ART (assisted reproductive technology) is ovarian hyperstimulation syndrome which leads to higher frequency of miscarriages and can be fatal for a woman. Since more that one embryo is usually transferred in ART children conceived with the help of this method can face different problems related to multiple pregnancy such as higher risk of preterm birth, higher risk of congenital disorder or intrauterine growth retardation. Key words: ART, assisted reproductive technology, infertility, congenital disorder, multiple pregnancy
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