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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Zkouška z češtiny pro trvalý pobyt v České republice / The examination in the Czech language for permanent residence in the Czech republic

Fimanová, Barbora January 2019 (has links)
This thesis deals with the examination in the Czech language for permanent residence in the Czech Republic. The aim is to identify its basic characteristics, the success rate of the participants and whether it corresponds to the required A1 level. In the theoretical part, basic theoretical concepts of migration and integration and conditions for granting permanent residence in different countries are presented. In the practical part, the analysis itself is elaborated. It consists mainly in the comparison of the exam with the publication Referenční popis češtiny pro účely zkoušky z českého jazyka pro trvalý pobyt v ČR - úrovně A1, A2 and evaluation of its integration potential. Included in the considerations are data on average results and success rates of candidates in the period January 24, 2018 - April 24, 2019. From a didactic point of view, the thesis also deals with the available preparatory materials: a handbook Připravte se s námi na zkoušku z českého jazyka pro trvalý pobyt v ČR. Nový formát testu A1, web portal www.cestina-pro-cizince.cz and related documents. This part evaluates the information about the test and how much the materials correspond to the exam. The results showed that the success rate of candidates is only 61.82% in the period under review. Despite the low results, we...
122

Varför är den relativa fitnessen högre för hanar av Drosophila melanogaster som bär allel A2 jämfört med allel A1 på genen CG3598? : Experimentell studie på bakomliggande faktorer till skillnad i fitness hos hanar med olika allel varianter på gen CG3598 / Why is the relative fitness greater for male Drosophila melanogaster carrying the allel A1 compared to allel A2 on the gene CG3598? : Experimental study on understanding why there is a male fitness difference between different alleles on the gene CG3598

Kilhage, Joel January 2023 (has links)
Sexual conflict is a term that describes the situation where traits can experience opposing selection pressures in the two sexes. Theory suggests this conflict exists in all organisms with separate sexes, and specific chromosome clusters which are possibly sexually antagonistic have been identified in the species Drosophila melanogaster. One of all identified genes is CG3598, which have proved yielding higher fitness for males carrying allele A2 on this gene compared to A1. In this study, factors which contribute to the difference in fitness between these two alleles, with regards to sperm competition and mating success were observed. A double mating design was used, in which males and females were placed in test tubes together in order to examine the number of copulations and the defensive (P1) and offensive (P2) ability of sperm. The relative fitness of males carrying A1 did not differ from males carrying A2, which rejects previous studies, however, A2 had a higher defensive capability compared to A1. On the other hand, A1 instead had better offensive capability and higher amount of rematings. This indicates that the defensive capability of A2 is very strong and opposes the offensive capability of A1, but also the increased rate of rematings in A1. To get a more precise understanding of the fitness relation between A1 and A2 on the gene CG3598, further experiments would need to be performed on the subject. / Sexuell konflikt är ett begrepp som beskriver förhållandet där egenskaper upplever olika selektionstryck beroende på kön. Teorier finns om att den här konflikten existerar i alla organismer med olika kön, och i arten Drosophila melanogaster har det identifierats specifika kromosomkluster som har möjlighet att bidra till sexuell konflikt. En utav alla identifierade gener är CG3598 som har påvisats ge en högre fitness för hanar bärande allel A2 på denna gen jämfört med allel A1. I den här studien undersöks bakomliggande faktorer till skillnaden i fitness mellan dessa två alleler, med avseende på spermiekonkurrens och parningsframgång. Genom en dubbel parningsdesign, där hanar och honor placerades tillsammans i rör undersöktes den defensiva spermieförmågan (P1), den offensiva förmågan (P2) och antal parningar. Den relativa fitnessen hos hanar med A1 skiljde sig inte från A2, vilket motsäger tidigare studier. Däremot var den defensiva förmågan högre för A2 och A1 hade istället högre offensiv förmåga samt en högre andel omparningar. Detta indikerar att A2 har en stark defensiv förmåga som motsätter den offensiva förmågan i A1 men också möjligheten till fler omparningar. För att få en mer precis uppfattning skulle ytterligare experiment behöva utföras då det i denna studie var en väldigt låg andel hanar som parade sig jämfört med vad som förväntas.
123

The role of hnRNP A1 and hnRNP C1/C2 in the regulation of the stress responsive genes Cyp2a5/2A6 and p53.

Christian, Kyle January 2008 (has links)
<p>The family of proteins known as heterogeneous nuclear ribonucleoproteins (hnRNPs) is large and diverse. Often, one and the same hnRNP will perform multiple cellular functions, leading to their description as “multifunctional proteins”. The two hnRNPs known as hnRNP A1 and hnRNP C1/C2 are multifunctional proteins found to affect the transcription, splicing, stability, and translation of specific genes’ mRNA. They are implicated in carcinogenesis, apoptosis, and DNA damage response mechanisms.</p><p>The aims of this thesis were to study the hnRNP A1 and hnRNP C1/C2 dependent regulation of two highly stress responsive genes, the tumor suppressor p53 and the cytochrome P450 enzyme <i>Cyp2a5/CYP2A6</i>. We identified hnRNP C1/C2 as a DNA damage induced binding protein towards the coding region of p53 mRNA, and found that while a specific <i>cis</i> binding site appears to have a positive function in p53 expression, interaction of hnRNP C1/C2 with this site represses the expression. The data suggest that two distinct molecular mechanisms exist for the down-regulation of p53 by hnRNP C1/C2. One mechanism, active during transcriptional stress, is dependent upon the aforementioned site, and the other, independent. We discuss how hnRNP C1/C2 dependent repression of p53 may play a role in apoptosis. </p><p>The data presented here further suggest that the transcriptional and post-transcriptional processes controlling the expression of the murine <i>Cyp2a5</i> gene are linked <i>via</i> hnRNP A1, by performing functions in the nucleus as a transcription factor, or in the cytoplasmic compartment as a <i>trans </i>factor bound to the 3’UTR of the mRNA as needed. Our studies of the human ortholog of this gene, <i>CYP2A6</i>, suggest that this gene is regulated post-transcriptionally in a manner similar to that of its murine counterpart, <i>via</i> changes in mRNA stability and interaction of hnRNP A1 with its 3’ UTR. </p>
124

Influence de TDP-43 sur la régulation de hnRNP A1 : un impact potentiel sur la sclérose latérale amyotrophique

Stabile, Stéphanie 12 1900 (has links)
La SLA est une maladie neurodégénérative fatale se déclenchant tardivement. Elle est caractérisée par la perte des neurones moteurs supérieurs et inférieurs. Jusqu’à présent, aucun traitement ne permet de ralentir ou de guérir la maladie de façon robuste. De récentes découvertes portant sur TDP-43 et hnRNP A1 y ont identifié des mutations reliées à des cas de SLA. Comme les deux possèdent de multiples fonctions dans le métabolisme de l’ARN, l’impact de ces mutations devient difficile à définir. Notre hypothèse est que TDP-43 régule hnRNP A1 et que les mutations causant la SLA dérégulent ce mécanisme, aboutissant ainsi à un impact majeur sur la vulnérabilité des neurones moteurs. Nos résultats démontrent que TDP-43 lie l’ARNm de hnRNP A1, mais n’affecte pas sa stabilité. En revanche, TDP-43 réprime l’expression de hnRNP A1. Ce mécanisme pourrait être appliqué in vivo où le ratio protéique hnRNP A1B/A1 augmente chez les souris âgées et davantage chez les TDP-43A315T dans la région cervicale et lombaire de la moelle épinière. Cette différence n’est pas causée par un défaut de l’épissage alternatif. Aussi, la mutation TDP-43A315T serait davantage responsable de cette différence que la surexpression de TDP-43 (résultats obtenus en culture). L’impact d’une telle augmentation sur la cellule pourrait être la formation d’agrégats puisque la forme hnRNP A1B possède quatre domaines de fibrillation de plus que hnRNP A1. Nos résultats pourraient donc fournir un mécanisme potentiel de la formation d’inclusions cytoplasmiques reconnues comme étant une des caractéristiques pathologiques principales de la SLA. / ALS is a fatal and late onset disease characterized by the selective loss of lower and upper motor neurons. Yet, there is no way to robustly slow or cure the disease. Recent discoveries concern TDP-43 and hnRNP A1 where mutations have been identified in ALS cases. Both have multiple functions in RNA metabolism, making the impact of mutations difficult to define. Our hypothesis is that TDP-43 regulates hnRNP A1 and that the ALS causative mutations deregulate this mechanism, having a major impact on the vulnerability of motor neurons. Our results demonstrate that TDP-43 binds hnRNP A1 mRNA, but does not affect its stability. In contrast, TDP-43 represses the expression of hnRNP A1. This mechanism could be applied in vivo where hnRNP A1B/A1 protein ratio increases in aged mice and even more in TDP-43A315T mice in the cervical and lumbar region of the spinal cord. This difference is not caused by a defect in alternative splicing. Also, the TDP-43A315T mutation would be more responsible for this difference than the overexpression of TDP-43 (result from cell culture). The impact of that increased on the cell could be the formation of aggregates since the shape of hnRNP A1B has four more areas of fibrillation than hnRNP A1. Our findings could thus provide a potential mechanism for the formation of cytoplasmic inclusions recognized as one of the main pathological features of ALS.
125

Úloha autofagie v indukcii apoptózy mastnými kyselinami u pankreatických beta buniek / The role of autophagy in apoptosis induction by fatty acids in pancreatic beta cells.

Žigová, Ivana January 2013 (has links)
Type 2 diabetes mellitus represents a metabolic disease reaching epidemic dimensions in the 21st century. Fatty acid-induced apoptosis of pancreatic β-cells significantly contributes to its pathogenesis. Saturated fatty acids (FAs) are strongly cytotoxic for β-cells, whereas unsaturated FAs are well tolerable by β-cells, they are even able to inhibit proapoptotic effects of saturated FAs when co-incubated. According to recent studies, FAs-induced apoptosis in pancreatic β-cells is partly regulated by autophagy, a catabolic process involved in the degradation and recyclation of cell components in lysosomes. The aim of this diploma thesis was to contribute to the clarification of the role of autophagy in FAs-induced apoptosis regulation. We induced apoptosis in human pancreatic β- cell line NES2Y by 1 mM stearic acid (SA) and inhibited it with 0.2 mM oleic acid (OA) co- incubated with SA. We revealed, that the saturated SA used in apoptosis-inducing concentration simultaneously inhibits the autophagic flux in pancreatic NES2Y cell line. When SA is co- incubated with unsaturated OA in concentration sufficient for inhibition of proapoptotic effect of SA, OA is also able to inhibit the block of autophagy induced by the effect of SA. Application of unsaturated OA alone in this concentration did not...
126

Effects of a putative Reb1 protein binding site on IME4 sense and antisense transcription and sporulation in Saccharomyces cerevisiae

Ramsay, Milele 20 December 2009 (has links)
Genome transcription is much more widespread than has been traditionally thought because our view of a "gene" or "transcription unit" has changed dramatically over the past 4 to 5 years with the identification of many different non-coding ribonucleic acids. In the yeast, Saccharomyces cerevisiae, meiosis and sporulation are an important part of the life cycle and IME4 gene expression is required for these processes. IME4 sense transcript levels of expression are influenced by the level of its complementary non-coding antisense strand by mechanisms that are currently unknown. The a1-alpha2 heterodimer binding in the downstream 3' region of IME4 is one component required for repression of IME4 antisense transcription. However, this thesis shows that the general regulatory protein Reb1 is also required in this system. Reb1 involvement is most likely to create a nucleosome-free zone in the promoter region of the IME4 antisense strand therefore contributing to transcription.
127

Efeito da dexametasona na proteômica do fluido endometrial de éguas suscetíveis a endometrite / Effect of dexamethasone on proteomics of endometrial fluid from mares susceptible to endometritis

Arlas, Tamarini Rodrigues January 2014 (has links)
A corticoterapia tem sido utilizada frequentemente nas éguas suscetíveis. O uso de isuflupredona melhora a taxa de prenhez e altera o perfil proteico do líquido endometrial em relação a éguas não tratadas. A utilização de dexametasona diminui o acúmulo de líquido pós-cobertura, reduz o edema do útero, porém, desconhecem-se seus efeitos no perfil proteico do líquido endometrial. O objetivo do presente estudo foi analisar o efeito da dexametasona em éguas suscetíveis à endometrite persistente póscobertura sobre perfil proteico do líquido endometrial na presença ou ausência de infecção. Nove éguas suscetíveis foram utilizados, com idade entre 7 a 30 anos. Após a verificação dos sinais de estro as éguas foram submetidas a quatro tratamentos: (C) éguas não receberam nenhum tipo de tratamento e serviram como controle; (D) éguas receberam 40mg de dexametasona (IV), no momento da cobertura, com coleta da amostras após 6 horas, (I-6 e I-24) infusão intra-uterina de 1 x 109 de S. zooepidemicus/mL, com coleta da amostra após 6 e 24 horas; (I/D-6 e I/D-24) infusão intra-uterina de 1 x 109 S. zooepidemicus/mL e administração de 40mg de dexametasona (IV), com coleta da amostra após 6 e 24 horas. Todas as éguas foram submetidas a todos os tratamentos. As amostras foram coletadas e submetidas à eletroforese bidimensional para separação proteica e espectrometria de massa para a identificação das bandas proteicas relevantes. A corticoterapia provocou alteração na proteômica do líquido endometrial de éguas suscetíveis, caracterizada pelo aumento (TTR) e/ou diminuição (ApoA1) na densidade óptica de proteínas da fase aguda da inflamação. Conclui-se que a utilização da dexametasona em éguas com e sem presença de infecção altera a proteômica do fluido endometrial de éguas suscetíveis. Sugere-se que a dosagem ou a frequência de aplicação da dexametasona deva ser aumentada. / Corticotherapy has often been used in susceptible mares. The use of isuflupredona improves pregnancy rate and alters the protein profile of the endometrial fluid in relation to untreated mares. The use of dexamethasone decreases the post breeding fluid accumulation, reduces the uterine edema, however is unaware of its effects on the protein profile of endometrial fluid. The aim of the present study was analyze the effect of dexamethasone in mares susceptible to post-breeding persistent endometritis on the protein profile of endometrial fluid in the presence or absence of infection. Nine susceptible mares were used, aged 7-30 years old. After checking the signs of estrus, mares were subjected to four treatments: (C) mares received no treatment and served as controls; (D) mares received 40 mg of dexamethasone at breeding time, with collection of samples after 6 hours; (I-6 and I-24) intrauterine infusion of 1 x 109 S. zooepidemicus/ml and the sample was collected after 6 and 24 hours; (I/D-6 and I/D-24) intrauterine infusion of 1 x 109 S. zooepidemicus/ml and 40 mg of dexamethasone administration, collecting the sample after 6 and 24 hours. All of the mares were subjected to all treatments. Samples were collected and subjected to two-dimensional electrophoresis for protein separation and mass spectrometry for the identification of relevant protein bands. Corticotherapy resulted in alteration of the protein profile of the endometrial fluid of susceptible mares, characterized by an increase (TTR) and/or decrease (ApoA1) in optical density of the acute phase of proteins of inflammation. We conclude that the use of dexamethasone in mares with and without the presence of infection alters the protein profile of endometrial fluid of susceptible mares. It is suggested that the dosage or frequency of application of dexamethasone should be increased.
128

Regulation of Mast Cell Survival

Möller, Christine January 2004 (has links)
<p>Mast cells are long-lived effector cells of importance for both acute and chronic inflammations. Mast cells can be activated in many different ways, leading to the release of inflammatory mediators. In contrast to most other inflammatory cells, activated mast cells have the capacity to recover, regranulate and thereby be activated again. </p><p>In this thesis I have investigated the mechanisms involved in regulating activation-induced mast cell survival. We have found that cross-linking of FcεRI-bound IgE with an antigen (IgER-CL) induces a survival program in mast cells. Upon IgER-CL, mouse and human mast cells upregulate the pro-survival Bcl-2 family gene A1/Bfl-1. A1<sup>-/-</sup> mast cells degranulate upon FcεRI activation but they cannot recover most likely due to the lack of A1. Sensitized and provoked A1<sup>-/-</sup> mice exhibit lower amounts of mast cells compared to littermate controls. In contrast to mast cells, no Bfl-1 expression or survival promotion can be detected in basophils after IgER-CL. Another mast cell secretagogue, an adenosine receptor agonist, neither promoted upregulation of A1 nor survival.</p><p>Although it is well established that mast cell survival is dependent on stem cell factor (SCF), it has not been described how this process is regulated. We have found that SCF promotes survival through Akt-mediated inhibition of the forkhead transcription factor FOXO3a and its transcriptional target Bim, a BH3-only pro-apoptotic protein. SCF-treatment prevents upregulation of Bim protein expression and leads to an upregulation of Bim phosphorylation through PI3-kinase and MEK-dependent pathways. Overexpression of FOXO3a causes an upregulation of Bim and induces mast cell apoptosis, even in the presence of SCF. </p><p>Taken together, the work in this thesis demonstrates that A1/Bfl-1 and Bim play key roles in mast cell survival. These findings might be of importance in understanding the mechanisms of mast cell longevity and hence for possible new therapeutics used for mast cell-associated inflammations.</p>
129

Regulation of Mast Cell Survival

Möller, Christine January 2004 (has links)
Mast cells are long-lived effector cells of importance for both acute and chronic inflammations. Mast cells can be activated in many different ways, leading to the release of inflammatory mediators. In contrast to most other inflammatory cells, activated mast cells have the capacity to recover, regranulate and thereby be activated again. In this thesis I have investigated the mechanisms involved in regulating activation-induced mast cell survival. We have found that cross-linking of FcεRI-bound IgE with an antigen (IgER-CL) induces a survival program in mast cells. Upon IgER-CL, mouse and human mast cells upregulate the pro-survival Bcl-2 family gene A1/Bfl-1. A1-/- mast cells degranulate upon FcεRI activation but they cannot recover most likely due to the lack of A1. Sensitized and provoked A1-/- mice exhibit lower amounts of mast cells compared to littermate controls. In contrast to mast cells, no Bfl-1 expression or survival promotion can be detected in basophils after IgER-CL. Another mast cell secretagogue, an adenosine receptor agonist, neither promoted upregulation of A1 nor survival. Although it is well established that mast cell survival is dependent on stem cell factor (SCF), it has not been described how this process is regulated. We have found that SCF promotes survival through Akt-mediated inhibition of the forkhead transcription factor FOXO3a and its transcriptional target Bim, a BH3-only pro-apoptotic protein. SCF-treatment prevents upregulation of Bim protein expression and leads to an upregulation of Bim phosphorylation through PI3-kinase and MEK-dependent pathways. Overexpression of FOXO3a causes an upregulation of Bim and induces mast cell apoptosis, even in the presence of SCF. Taken together, the work in this thesis demonstrates that A1/Bfl-1 and Bim play key roles in mast cell survival. These findings might be of importance in understanding the mechanisms of mast cell longevity and hence for possible new therapeutics used for mast cell-associated inflammations.
130

Clinical and genetic studies of three inherited skeletal disorders

Stattin, Eva-Lena January 2009 (has links)
Mutations in genes of importance for cartilage development may lead to skeletal malformations, chondroskeletal dysfunction and increased susceptibility to degenerative joint disease. Characterization of these mutations and identification of molecular pathways for the corresponding gene products have contributed to our understanding of mechanisms regulating skeletal patterning, endochondral ossification and joint formation. A five generation family segregating autosomal dominant osteochondritis dissecans (OCD) was identified. Affected family members presented with OCD in knees, hips and elbows, short stature, and early osteoarthritis. A genome wide scan and a multipoint linkage analysis identified aggrecan (ACAN) as a prime candidate gene. DNA sequence analysis of the ACAN-gene revealed heterozygosity for a missense mutation (c.6907G&gt;A) in affected subjects, resulting in a p.V2303M substitution in the aggrecan G3 domain C-type lectin. This domain is important for the interaction with other proteins in the cartilage extracellular matrix. To determine the effect of the V2303M substitution on secretion and interaction, we performed binding studies with recombinant mutated and wild type G3 proteins. We found decreased affinity or complete loss of interaction between V2303M aggrecan and fibulin1, fibulin2 and tenascin-R. Analysis of articular cartilage from an affected family member confirmed that V2303M aggrecan is produced and present. In search for gene mutations associated with multiple epiphyseal dysplasia (MED) we considered the ACAN-gene a likely candidate. The ACAN-gene was analysed in 39 individuals with MED and screened negative for mutations in six previously known MED genes. Sequence analysis revealed a heterozygous missense mutation (c.1448G&gt;T) in one adult male and compound heterozygous missense mutations (c.1366T&gt;C and c.836G&gt;A) in a five year old boy with healthy parents, each of them carrier for one of the mutations. A large family segregating autosomal dominant brachymesophalangia and OCD in finger joints was characterised. The clinical presentation in six affected family members was consistent with the diagnosis Brachydactyly type A1, in this family characterized by shortening of the middle phalanges, short ulnar styloid process, flattening of the metacarpal heads and mild osteoarthritis. The condition may be caused by mutations in the Indian hedgehog gene (IHH) or a yet unidentified gene on chromosome 5p13. Sequence analysis of the IHH-gene in affected individuals revealed a novel C to T transition (c.472C&gt;T) leading to a p.158Arg&gt;Cys substitution. Residue 158 in IHH is highly conserved throughout evolution and molecular structure modelling of IHH suggests that the R158C substitution leads to a conformational change at the site of interaction with the IHH-receptor. This supports that the substitution causes Brachydactyly type A1 in this family. In summary, we report on the clinical, radiological and molecular genetic characteristics of the three skeletal disorders OCD, MED and BDA1. Our results provide a novel molecular mechanism in the pathophysiology of familial osteochondritis dissecans confirming the importance of aggrecan C-type lectin for cartilage function. We also show that ACAN-gene mutations may be associated with MED extending the spectrum of skeletal dysplasias associated with the aggrecan gene. Finally, we report on a novel missense mutation in a conserved region of the IHH-gene associated with BDA1.

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