|
|
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...
|
|
|
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...
|
|
|
Craniofacial Abnormalities in Sleep Apnoea Syndrome
Dostálová, Simona ; Šonka, Karel (advisor) ; Čáp, Jan (referee) ; Peterka, Miroslav (referee)
The thesis is based on a series of cephalometric studies of patients with SAS, acromegalic patients with or without SAS as well as control groups. The studies presented in this thesis produce following results: There are important differences in orofacial skeleton and soft tissue of nasopharynx measured by cephalometry in the patients with sleep apnoea compared to the control group of women and men. Proved skeleton changes (increased lower gonion angle, increased anterior facial heights, decreased depth of the upper face) and elongated soft palate predisposes patients to narrowing of upper airways in oropharyngx, which significantly contributes to development of SAS. Cephalometric differences in the size of the soft palate, the rotation of the mandible and the size of lower gonion angle can be found in men with mild and severe sleep apnoea. We conclude that the severity of the SAS depends on the degree of changes in the orofacial skeleton and adjacent soft tissues. The results, which reveal a significant differences in BMI and in the circumference of the neck between groups with mild and severe SAS, confirm the idea that the most important predisposing factor for SAS is obesity, in particular deposition of adipose tissue in the posteriolateral parapharyngeal space. Patients with acromegaly (of both sexes)...
|
|
|
The issue of diabetes treatment and prevention of birth defects.
Steklíková, Klára ; Peterka, Miroslav (advisor) ; Peterková, Renata (referee)
This work summarizes observations of relationship between diabetes in pregnancy and increased risk of birth defects and possible preventive measurements to reduce this risk. Children of diabetic mothers have an increased risk especially for the development defects of central nervous system (three times higher), cardiovascular system (1,5-4,5times higher), urinary system (2,5-3times higher). Other organ systems with increased risk of birth defects are musculo-skeletal system, digestive system and ear. To minimalize this risk the effective measures have to be kept, especially maintain blood glucose standard and without peaks. To achieve this goal is necessary observe appropriate diet and by types of diabetes requiring medication use choosing suitable drugs for pregnant women. Each pregnant patient should periodically measure blood glucose levels and don't exceed threshold 90 mg/ml (5,0mmol/l) of fasting and premeal level and 150 mg/ml (8,4 mmol/l) after meal. Also important is awareness of patient. Other tools used for prevention infants birth defects of diabetic mothers are regular measurements of glycohemoglobin levels, preconception planning and screening performed in pregnant women. Keywords: Diabetes, birth defects, pregnancy, prevention
|
|
|
Genetic Regulation of Limb Development
Šnajdr, Pavel ; Grim, Miloš (advisor) ; Peterka, Miroslav (referee) ; Slípka, Jaroslav (referee)
Lx in SHR.Lx rat manifests in homozygotes as hindlimb preaxial polydactyly. We showed that a 2,964-bp deletion in Plzf (Promyelocytic leukemia zinc finger) intron 2 is the only candidate for Lx. The deletion removes the most deeply conserved CNE with putative regulatory influence on Plzf expression. Using in situ hybridization we found reduced expression pattern of Plzf in Lx/Lx limb and anterior expansion of expression domains of Plzf targets Hoxd10-13 genes and Bmp2, in the absence of ectopic Shh expression. Rat hd manifests in homozygotes as reduction or loss of digits II and III on both hind and forelimb and impairment of spermatogenesis leading to male infertility. We showed that hd mutation is caused by an insertion of an endogenous retrovirus into intron 10 of the Cntrob gene resulting in the translation of a truncated protein. In situ hybridization showed that expression of cartilage condensation marker Sox9, and Bmp receptor Bmpr1b is absent from the distal parts of the digit condensations II and III. Studying spermatogenesis we showed that centrobin (protein of Cntrob) localizes to the centrosome, manchette, and the marginal ring of the spermatid acroplaxome. Mutant spermatids show a disruption of head-tail coupling apparatus leading to spermatid decapitation . We demonstrated distinct...
|
|
|
Testing of drugs embryotoxicity on chicken embryo
Steklíková, Klára ; Peterka, Miroslav (advisor) ; Buchtová, Marcela (referee)
The embryonal development could be negatively disrupted by exogenous factors, which could cause developmental defect. These factors are called teratogens and amongst them there are not only physical and biological but also chemical substances including some of commonly used drugs. Those substances are recommended not to be use in pregnancy. In case of women with chronical disease, for example diabetes mellitus, permanent medication is necessary also during pregnancy. Therefore it is important to ensure medicament and dose, which are safe for use during pregnancy. For finding out the embryotoxicity of drugs the prospective and retrospective epidemiological studies are used, which are supplemented by results from experimental studies. According to OECD (organization for economic co-operation and development) recommendations the classical testing is performed on two different mammalian species. Those experiments are limited by different pharmacokinetics and biotransformation, which affects substances in maternal organism. Therefore for alternative embryotoxicity testing are used such methods, that exclude this impact. One of these model organisms that enable this is chicken embryo. Chicken embryo, unlike cellular and tissue cultures, can provide complex information about effect of tested substance on...
|
|
| |
|
|
Testing of drugs embryotoxicity on chicken embryo
Steklíková, Klára ; Peterka, Miroslav (advisor) ; Buchtová, Marcela (referee)
The embryonal development could be negatively disrupted by exogenous factors, which could cause developmental defect. These factors are called teratogens and amongst them there are not only physical and biological but also chemical substances including some of commonly used drugs. Those substances are recommended not to be use in pregnancy. In case of women with chronical disease, for example diabetes mellitus, permanent medication is necessary also during pregnancy. Therefore it is important to ensure medicament and dose, which are safe for use during pregnancy. For finding out the embryotoxicity of drugs the prospective and retrospective epidemiological studies are used, which are supplemented by results from experimental studies. According to OECD (organization for economic co-operation and development) recommendations the classical testing is performed on two different mammalian species. Those experiments are limited by different pharmacokinetics and biotransformation, which affects substances in maternal organism. Therefore for alternative embryotoxicity testing are used such methods, that exclude this impact. One of these model organisms that enable this is chicken embryo. Chicken embryo, unlike cellular and tissue cultures, can provide complex information about effect of tested substance on...
|
|
|
Embryotoxicity testing of psychopharmacs using the CHEST method
Pavlovič, Ondřej ; Peterka, Miroslav (advisor) ; Maňáková, Eva (referee)
Psychotropic drugs are commonly used group of pharmaceuticals, their main effect is to alter psychic condition, including mental diseases treatment. Symptoms of mental illnesses are more and more common, theref orenumber of patients diagnosed with mental illnes, and thus using psychotropics, is growing stronger. But using psychotropics during gestation is not without risks for mother and embryo itself. However, thanks to the absence of controlled human studies, the knowledge of emrbyotoxic effects of pschotropics is limited to casuistics, reported side effects and animal experimental studies. Many of those studies suggests emrbyotoxic potential of psychotropic drugs, on the other hand, others claim their safety. The goal of this thesis is to test at least some of them, using CHEST method, that allows us to observe direct effect of unmetabolized substance on chick embryo. In this thesis we tested selected psychotropics, very common antidepressant fluoxetine (prozac) and antipsychotic drug olanzapine, for embryotoxicity, using in ovo method CHEST with chick embryos as model organism. By bypassing the maternal organism and his metabolism, this method allows to observe direct effect of unmetabolized substance on chick embryo. Results revealed embryotoxic effect of fluoxetin in dosage 10-2 and 10-3 on 3rd and...
|
|
|
Functional role of ISLET1 in the neurosensory development of the inner ear.
Hampejsová, Zuzana ; Pavlínková, Gabriela (advisor) ; Peterka, Miroslav (referee)
Loss of hearing affects more than 10 % of the population, and one newborn in a thousand is born with defects of the inner ear. Transcriptional factors involved in the development of inner ear are important in our understanding of the causes of inner ear defects. ISLET1 is one of these factors. ISLET1 expression is detected in the sensory and neuronal cells of the inner ear. It participates in otocyst formation, and the specification and differentiation of cells of cochlea and vestibular system. The functional role of ISLET1 during inner ear development was investigated. Its role was studied by using Pax2-Isl1 transgenic mice that overexpress Islet1 under the control of the Pax2 promoter. Two transgenic lines were generated, Pax2-Isl1/300 and Pax2- Isl1/52. Two copies of the Pax2-Isl1 transgene were inserted to Pax2-Isl1/300 genome and one copy was inserted to the Pax2-Isl1/52 genome. Defects in sense of hearing were detected in both lines and circling behavior, a defect of balance, was detected in the Pax2-Isl1/300 transgenic mice. We observed high postnatal lethality in heterozygote transgenic mice. Pax2-Isl1/52 homozygote mutation is lethal at embryonic day 10 (E10,5). Pax2-Isl1/300 homozygote letality couldn't be detected because of the inability to breed heterozygote mutated mice of this line....
|
guest ::
RSS feed.