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Crystallographic study of the iron-regulated outer membrane lipoprotein (FrpD) from Neisseria meningitidis
SVIRIDOVA, Ekaterina
Neisseria meningitidis (N. meningitidis) is a Gram-negative commensal bacterium colonizing nasopharynx of about 10 % of healthy individuals, which can cause invasive diseases, such sepsis and meningitis, upon occasional penetration into bloodstream. Pathogenesis of N. meningitidis appears to be directly related to conditions of limited iron availability. Under these conditions two proteins of unknown function: FrpC and FrpD, are synthesized. FrpD is a highly conserved lipoprotein of N. meningitidis anchored to the bacterial outer membrane. It is known that FrpD tightly binds the FrpC protein, which belongs to the Repeat-in-Toxin (RTX) protein family and may act as bacterial exotoxin. However, the mechanism of FrpD-FrpC interaction and the exact function of this complex are unknown due to the absence of structural information on these proteins. Therefore, we set out to determine the structure of FrpD and provide insights into its interaction mechanism with FrpC and structure-functional relationships of these two proteins. We determined the first crystal and solution structures of the FrpD protein. We found that atomic structures of FrpD reveal a novel protein fold. We uncovered the structure-function relationships underlying the mechanism of interaction between the FrpD and FrpC proteins and tested the putative function of the FrpD-FrpC1-414 complex in vitro. Finally, we proposed the putative function of the FrpD-FrpC1-414 complex as a new minor adhesin of N. meningitidis, which mediates the bacterial adhesion to the host epithelial cells and facilitate the colonization. Our work constitutes the first step in clarifying the molecular basis of the FrpD-FrpC interaction and sets the base for further investigation of the role of FrpD and FrpC in the virulence mechanism of N. meningitidis.
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Mechanochemical Preparation of Alumina-Ceria
Jirátová, Květa ; Spojakina, A. ; Tyuliev, G. ; Balabánová, Jana ; Kaluža, Luděk ; Palcheva, R.
Ceria containing catalysts play an essential role in heterogeneous catalytic processes. However, ceria shows poor thermal stability and low specific surface area and therefore, many studies have been done to improve its properties by combination with other oxides. Alumina-ceria is substantial component of the three ways catalysts, due to the ceria ability to function as the buffer of oxygen and to enhance the oxygen storage capacity of the catalysts. Ceria in these catalysts also functions as structural promoting component, increasing alumina stability towards thermal sintering. Promising method of oxides preparation, very interesting and simple but not sufficiently studied yet is a mechanochemical synthesis. Here we report on the synthesis of nano-sized alumina, ceria and ceria-alumina of various compositions by a wet solid phase mechanochemical reaction of hydrous aluminum, and/or cerium nitrate with ammonium bicarbonate after addition of a small amount of water. The aim of this contribution is to study processes being in progress during synthesis of the mixed oxides, interaction between components and their mutual effect on the properties of resulting products. The phase evolution during mechanical milling and the subsequent heat treatment of precursors were studied by X-ray diffraction, DTA/TG, H2-TPR, NH3-TPD, CO2-TPD, N2 adsorption at -195°C, IR, and XPS spectroscopy. Alumina and mixtures of alumina with different quantities of CeO2 (1- 18 wt. %) were synthesized by mechanochemical method from aluminum nitrate, cerium nitrate and ammonia bicarbonate.
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Plný tet: SKMBT_C22015083108560 - PDF
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Human and social capital in primary education
KOKŠTEIN, Jiří
The thesis contains a theoretical insight into the studies that the issue of human and social capital involved from different perspectives, engage their evolution over time, their measurability, examine them, and complemented with other evidence. This part contains relation of human and social capital in relation to the aging of the human population and focuses on the human capital of older workers. Theoretical study ends with an insight into the basic education, the role of teacher and seeks to provide information on surveys already conducted in the area of education, which in the application of serve for me compared to the data obtained from the survey. The application part is focused on the teaching staff of primary schools. Education in currently globalized world, changing not only its content but also methods and forms of work. Irreplaceable role in this process is played by educators. To meet all the demands placed on them, it is essential that they pay close attention to their continuing education and sharing of acquired education, which is essential to the growth of human and social capital, because they are interacting. The work examines selected sample of teachers and approaches to this issue by detecting what is education motivates them whether they are satisfied with the benefits of educational events, what type of education they prefer etc. Working findings further analyzes looking for relationships between age and sex educators according to the hypotheses . Educator is someone who is in constant contact with other people. This of course also formalizes its attitudes and experiences. As a human being perceives the views of society and shapes on her own views, which it subsequently may influence the exercise of his profession. Therefore, in this part of the thesis is dedicated to exploring and bridging social capital, which determines the size of the circle of people with whom the teachers generally meet and interact. The last research that is possible to find thesis, it is perceptions of social status of teachers by themselves.
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Expression of selected proteins in sperm in men with normal and pathological spermiograms using monoclonal antibodies
Pěknicová, Jana ; Čapková, Jana ; Dorosh, Andriy ; Margaryan, Hasmik ; Kubátová, Alena ; Děd, Lukáš
Recent studies show that infertility in human populations it affects an estimated 15% of couples of reproductive age. Male infertility is the primary cause for 60% of these cases. For these reasons, we analyzed the acrosomal and sperm surface proteins in men with normal and pathological spermiograms. We found that intra-acrosome proteins: TERA (Transitional endoplasmic reticulum ATPase), GAPDHS (Sperm Glyceraldehyde-3-phosphate dehydrogenase), and PRKAR2A (C-AMP-dependent protein kinase II, PRKAR2A), which can be identified using our monoclonal antibodies, are different express in healthy men and men with astenozoospermia (with reduced sperm motility), and with a significantly reduced expression in the astenozoospermia. These proteins are involved in energy metabolism and apoptosis of the cells, and some of them in the sperm-egg interaction; therefore, they have an important role in reproduction. On the other hand, there were no statistically significant differences in the expression of surface proteins (Appolipoprotein J (Clusterin) and Semenogelin). Our findings show that astenozoospermia as a complex disorder of the semen is often combined with other pathological conditions that are not diagnosed by the semen analysis. Therefore monoclonal antibodies are so suitable instrument for the detection of proteins associated with the pathology of the sperm in the semen with low sperm motility. In general, monoclonal antibodies against the sperm proteins are an appropriate tool to detect sperm quality in reproductive medicine.
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Estrogen receptor beta (ERβ) in testicular cells and sperm
Dostálová, Pavla ; Žatecká, Eva ; Děd, Lukáš ; Dorosh, Andriy ; Postlerová, Pavla ; Jonáková, Věra ; Dvořáková-Hortová, Kateřina ; Pěknicová, Jana
Estrogen is a steroid hormone that plays an important role during sperm development in the male and female reproductive tract. Estrogen signalling is a complex process that depends on cell milieu and presence of receptors. Thanks to the steroid nature of estrogens, they can pass through the plasmatic membrane and bind to the intracellular estrogen receptors (ERs). Within the cell, there are several pools of ERs. One of them is localized to the cell nucleus and their activation leads to direct or indirect binding to DNA and ultimately to alternation in gene expression (genomic pathway). Other pools of ERs are associated with plasma membrane or are located in cytosol. Activation of membrane associated ERs leads to rapid non-genomic responses. Nowadays, two classical estrogen receptors are known – ERα and ERβ. Since ERβ is a predominant variant in testes, we focused our study on expression of ERβ variants in murine testes and sperm. We detected two variants of ERβ at mRNA level in both, testes and sperm. These variants differ in 54 nucleotids within the ligand binding domain and this variability results in different affinity to estrogen. We analyzed individual testicular cell types (spermatogonia, spermatocytes, spermatids, Sertoli cells) by RT-qPCR. Our results suggest that both ERβ variants are coexpressed in the same cell type and may therefore interact together. This may have consequences in mediating of estrogen signalling. Moreover, ERβ is expressed more in the later stages of spermatogenesis suggesting the role of ERβ in these stages or alternatively in spermatozoa alone. At the protein level, we detected ERβ in nuclear, membrane and cytosolic fraction prepared from testicular tissue suggesting the involvement of both, genomic and non-genomic, pathways of estrogen signaling in testes. In sperm, anti-ERβ antibodies localized ERβ in acrosome region and tail which is in accordance with the known role of estrogen on capacitation, acrosome reaction and motility.
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Dynamics of mouse sperm capacitation and acrosome reaction
Dvořáková-Hortová, Kateřina ; Frolíková, Michaela ; Děd, Lukáš ; Šebková, Nataša
Capacitation followed by the acrosome reaction (AR), is a very complex event of molecular changes, including acrosome matrix rearrangement and actin polymerization, which mammalian sperm must undergo in the female reproductive tract in order to obtain the ability to penetrate and fertilize the egg. CD46 and β1-integrin belong to specific proteins, which are predicted to interact during molecular reorganization of capacitating sperm. The IZUMO1 as the primary fusion protein of the mammalian sperm is also involved in this dynamic network. We investigated the relationship between the Izumo, CD46 and β1 integrin relocation in the sperm head during the capacitation and AR in vitro. We have already successfully monitored by immunofluorescent labelling the dynamics of proteins CD46 and β1-integrin. The changes in the localization of these proteins associated with the AR and their mutual co-localization was observed. The original β1-integrin location in the freshly released epididymal sperm is in the acrosome and it relocates during the AR further through the sperm head compartments into the equatorial segment and over the whole sperm head. Its density over the equatorial segment is decreasing with the extended time of the AR. Also its presence in the perforatorium of the mouse sperm head is very prominent. The pattern for protein CD46 is extremely similar if not identical in both aspects such as compartment localization and time progress during capacitation and AR in vitro. The molecular interaction of CD46 and β1-integrin was investigated using the Proximity Ligation Assay and Super resolution microscopy STED. The data were statistically analysed. The newly obtained results from CD46 and β1-integrin relocation are in correlation with IZUMO1 dynamics and giving a substantial knowledge on the studied protein network rearrangement during capacitation and AR in mouse spermatozoa.
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Role and competences of the nurse in compared with Czech Republic and Namibia
KLYNCYPAROVÁ, Hana
Theoretical grounds The nursing profession among the professions and mission. Job nurse is one of very important professions. Nurse is an independent worker who has an irreplaceable role in the provision of care. In practice, certain roles, such as the role of a caregiver, the educationalist, communicator, the role of the lawyer, consultant, person, who brings the change, manager and researcher. These roles are constantly interacting and are interconnected. Health care has multidisciplinary and multiprofessional character. Although each of these professions contribute to care in a unique way, all share certain skills that are necessary to ensure the quality of care. Over the years there have been increasing professional skills and increase competencies. Expanded the range of services for which they previously did not have the competence or sisters had a written authorization of a doctor. This work is made up of theoretical and empirical part. The theoretical part provides an overview and information on the field of nursing and its history, dealing with the care system and education system in the Czech Republic and Namibia. The following list of findings roles and their importance in the nursing profession. The last part deals with the competencies of nurses in both countries. The aim of the thesis: The aim of the study was to determine the roles and responsibilities of nurses in the Czech Republic and Namibia. To to obtain this information were chosen research question what role nurses advocate in the Czech Republic and Namibia, and what are nurses in the Czech Republic and Namibia competence. Methods: To ensure the necessary data and information was chosen qualitative research through deep interviews. Nurses who were interviewed were from a hospital in the Czech Republic and nurses from hospitals in Namibia Keetmanshoop. All interviews were recorded on a Dictaphone andwritten down on the paper. Results: Recorded interviews were analyzed after writing down, we were using paper and pencil methods. Dialogs were openly coded. The analysis of these data arose following categories: the role of caregivers, the role of the teacher, communicator, the lawyer's role, the role of counselor, role of person who brings the change, the role of leader, manager's role, the role of researcher and categories of competence. Individual categories were assigned to subcategories. All informationwere are illustrated by clear diagrams of the individual categories. Conclusion: The Research shows that nurses have a general maintenance of the roles and competencies, actually both of sides, Namibia and Czech Republic also. both groups were mostly able to define roles in nursing care. Surprisingly czech nurses most failed in the role of the Advocate, while African colleague have proven to be very informed. Research also showed negative effect of paperwork and administration in czech system. Nurses having feeling they do not provide active care as they would be able to. Czech nurses seems also low initiative and ambitious, Czech nurses do not desire for increasing competence on the other hand African nurses, who have more competencies, want still more, than they already have.
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Monetary Policy and Macroprudential Policy: Rivals or Teammates?
Malovaná, Simona ; Frait, Jan
This paper sheds some light on situations in which monetary and macroprudential policies may interact (and potentially get into conflict) and contributes to the discussion about the coordination of those policies. Using data for the Czech Republic and five euro area countries we show that monetary tightening has a negative impact on the credit-to-GDP ratio and the non-risk-weighted bank capital ratio (i.e. a positive impact on bank leverage), while these effects have strengthened considerably since mid-2011. This supports the view that accommodative monetary policy contributes to a build-up of financial vulnerabilities, i.e. it boosts the credit cycle. On the other hand, the effect of the higher bank capital ratio is associated with some degree of uncertainty. For these and other reasons, coordination of the two policies is necessary to avoid an undesirable policy mix preventing effective achievement of the main objectives in the two policy areas.
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Vliv teploty vody a intenzity světla na raný vývoj sumečka afrického v komerčním chovu
PROKEŠOVÁ, Markéta
The successful production of quality early fish stages is crucial for artificial rearing fish species. Nevertheless, it is quite a problematic process, because fish as poikilothermic organisms are highly sensitive to various environmental conditions. Moreover, both fish embryos and larvae are more affected by biotic and abiotic factors (such as predation, stocking density, temperature, light, pH, salinity, oxygen saturation, feeding availability, or their interactions) than older juveniles or adults. Most fish processes such as reproduction, metabolism, survival, development and growth can be considerably (positively, negatively or not) influenced by these conditions. Therefore, it is important to understand their impacts on fish stages during embryonic, larval, juvenile, adult, and eventually the senescent period. Then, following the application of new knowledge to the practise, especially species- and age-specific optimal conditions, should result in higher survival, better growth rate, well developed fish without deformities and lower cannibalism. The objectives of the present thesis were to assess the effect of water temperature and light intensity on the early development (embryonic and larval period) of African sharptooth catfish as a perspective fish species for freshwater intensive aquaculture. Due to its great characteristics (for instance fast growth, ability to breathe atmospheric air, rearing at high stocking density) this species can meaningfully contribute to the global aquaculture production which is expected to rise in the coming years. However, there are still some difficulties in the early rearing African sharptooth catfish regarding the cannibalism, feeding, survival and necessity of detailed information about the effects of some abiotic factors and their interactions.
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Holistic approach in providing nursing care for disabled children in the health and social facilities.
GUIDOVÁ, Hana
Holistic nursing care requires body and psyche orientation. That means it stresses both, body and psychosocial human needs. It is necessary for nurses to understand the principle of psychosocial interaction and care of the whole person including his/her dearest in health and illness. The aim of the thesis ?Holistic approach in providing nursing care to handicapped children in health & social facilities? was to find out how the needs of handicapped children are satisfied in health & social facilities from the point of view of holistic approach. The work involved both, qualitative and quantitative research. 104 nurses filled in a questionnaire and 10 respondents were observed within the quantitative research. Two hypotheses were set. The first hypothesis was focused on handicapped children in health & social facilities and on satisfaction of their needs from the point of view of holistic theory. Most of the nurses are convinced that they are providing holistic care. However on the other hand a lot of nurses answered that they preferred provision of physiological needs to psychosocial needs. This finding does not fully confirm the holistic approach in providing nursing care. The second hypothesis says that nurses provide more holistic care in non-profit making facilities than in those operated by regional authorities. Non-profit making facilities could not be included in the research as nurses are not employed there and those who work there work at the positions of social workers and caregivers, not at the positions of nurses. Comparison was only performed at facilities operated by private limited companies and the regional authority. The research also compared the approach to holistic nursing care between head nurses and ward sisters and nurses working on shifts. The nurse managers answered more positively than the nurses working on shifts. A nurse providing holistic care sees a human as a unique complex being, not as its single parts. Such a nurse is ready to help people achieve and maintain optimal health, helps in prevention and reduction of diseases and provides support to those incurably ill. It is important to realize that body and psyche are closely linked, not separated. This thesis may be used by nurses working with handicapped children in health & social facilities. Elaboration of a standard for holistic nursing care for handicapped children in health & social facilities is the practical output of the thesis.
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