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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.
51

Padrão de metilação do receptor de progesterona (PGR) em endométrio eutópico de pacientes com infertilidade relacionada à endometriose durante a fase secretora / Methylation pattern of progesterone receptor (PGR) on eutopic endometrium of patients with infertility related to endometriosis during stage secretory

Rocha Júnior, Carlos Valério da 08 December 2015 (has links)
A endometriose é uma doença caracterizada pelo crescimento de tecido endometrial ectópico histologicamente similar ao do endométrio eutópico. Dentre sua sintomatologia, encontra-se relatos de infertilidade a qual está relacionada à diminuição da receptividade endometrial e a resistência à progesterona, importante hormônio envolvido no estabelecimento desse processo e na manutenção da gestação. A etiologia da endometriose não é bem conhecida, mas estudos sugerem que essa desordem possa estar ligada a mecanismos epigenéticos de regulação da expressão genica, tais como a metilação do DNA. A receptividade endometrial à progesterona é mediada por receptores (PR-A e PR-B) a qual parece estar suprimida nessas pacientes, possivelmente por diminuição ou inatividade destes receptores, o que poderia ser um mecanismo envolvido na infertilidade associada à endometriose. Estudos de metilação no gene codificante das isoformas A e B do receptor de progesterona (PGR) mostram que o exon 1 da isoforma PR-B encontra-se hipermetilado e tem sua expressão silenciada em pacientes portadoras da doença. Entretanto ainda não foi avaliado o perfil de metilação deste gene em mulheres inférteis com a doença, o que poderia estar envolvido na infertilidade apresentada por essas pacientes. O objetivo desde estudo foi avaliar o padrão de metilação do gene PGR em endométrio eutópico de mulheres com infertilidade relacionada à endometriose e controles inférteis, durante a fase secretora. 10 Foram realizadas biópsias endometriais de 23 pacientes, divididas em dois grupos: 12 mulheres inférteis sem endometriose (Controle infértil) e 11 mulheres inférteis com endometriose (Endometriose). Todos os endométrios coletados foram confirmados na fase secretora do ciclo através de análise histológica clássica segundo os critérios de Noyes. O DNA genômico foi extraído com o QIAamp DNA Mini Kit e modificado utilizando o EpiTec Bissulfite Kit. O padrão de metilação das isoformas PR-A e PR-B foi avaliado pela técnica HRM (High Resolution Melting) A análise de metilação da isoforma PR-A mostrou que a região analisada encontra-se hipometilada, em que a porcentagem de metilaçao encontrada foi 0% em ambos os grupos com e sem endometriose. No entanto, no grupo com endometriose, a isoforma PR-B mostrou-se parcialmente metilada na maioria das pacientes com porcentagem de metilaçao de 50% (n=8), somente uma paciente apresentou 80% de metilacão na isoforma B. Para o grupo sem endometriose a isoforma PR-B mostrou-se hipometilada (0%). A hipometilação da isoforma PR-A sugere que este gene encontrar-se na sua forma ativa, sem alterações em sua expressão. No entanto, a hipermetilação da isoforma PR-B nas mulheres com endometriose pode estar relacionada com o silenciamento gênico ou redução da sua expressão, sugerindo que a baixa resposta à progesterona nas mulheres com endometriose pode estar diretamente ligada à redução do número de seus receptores nessas pacientes / Endometriosis is a disease characterized by ectopic growth of endometrial tissue histologically similar to the eutopic endometrium. Among this symptoms, is infertility accounts which is related to decreased endometrial receptivity and resistance to progesterone, important hormone involved in the establishment of this process and the maintenance of pregnancy. The etiology of endometriosis is not well known, but studies suggest that this disorder can be linked to epigenetic mechanisms of regulation of gene expression such as DNA methylation. The endometrial responsiveness to progesterone is mediated by receptors (PR-A and PR-B) which seem to be suppressed in these patients, possibly reducing or inactivity of these receptors, which could be a mechanism involved in the infertility associated with endometriosis. Studies in methylation of the gene encoding the A and B isoforms of progesterone receptor (PGR) showed that exon 1 of the PR-B isoform is hypermethylated and silenced have its expression in patients with the disease. However it has not been rated the methylation profile of this gene in infertile women with the disease, which could be involved in the infertility presented by these patients. The goal from study was to evaluate the methylation pattern of the PGR gene in eutopic endometrium of women with infertility related to endometriosis and infertile controls during the secretory phase. Endometrial biopsies were performed on 12 23 patients, divided into two groups: 12 infertile women without endometriosis (infertile Control) and 11 infertile women with endometriosis (Endometriosis). All endometrium collected were confirmed in the secretory phase of the cycle by classical histological analysis according to the criteria of Noyes. Genomic DNA was extracted with the QIAamp DNA Mini Kit and using the modified EpiTec Bissulfite Kit. The methylation pattern of PR-A and PR-B isoforms was assessed by HRM technique (Melting High Resolution) Methylation analysis of PR isoform The analyzed showed that the region is hipometilada, wherein the percentage of methylation was found 0% in both the groups with and without endometriosis. However, in the group with endometriosis, the PR-B isoform showed partially methylated in most patients with methylation percentage of 50% (n = 8), only one patient showed methylation in 80% of isoform B. In the group without endometriosis the PR-B isoform was shown hipometilada (0%). The hypomethylation of PR-A isoform suggests that this gene be in its active form, without change in his expression. However, hypermethylation of the PR-B isoform in women with endometriosis may be associated with gene silencing or reducing the expression, suggesting that the low response to progesterone in women with endometriosis can be directly linked to the reduction of its receptors in these patients
52

Inhibiting the IGF-1 receptor with the cyclolignan Picropodophyllin: an in vitro study of ovulation, implantation and receptivity in a mouse model

Larsson, Patrik January 2008 (has links)
Picropodophyllin (PPP) is an analogue of the anti tumour lignan podophyllotoxin with the unique ability to selectively inhibit the receptor of Insulin like growth factor 1(IGF-1). IGF-1 is believed to play an important part in development of the endometrium facing implantation. With PPP treated mice, studies can be made to measure gene expression from tissue of both treated and untreated mice to compare the role of IGF-1 regarding ovulation, implantation and receptivity. The aim of this study was to analyze gene expression of some steroid hormone receptors and cytokines in ovaries from mice treated with PPP. In this study, seven mice were treated with PPP at different times and tissue was collected. PCR-primers for cDNA sequences of estrogene receptor α, estrogene receptor β, progesterone receptor A, progesterone receptor B, growth hormone receptor, interleukin 1 α, interleukin 1 β, tumour necrosis factor α and androgen receptor were used. Real Time PCR was run with the samples and gene expression was measured. The results of this study showed that the inhibition of IGF-1 receptor interacted with IGF-1 which lead to altered levels of estrogene receptor alpha, progesterone receptor, growth hormone receptor and androgen receptor that can decrease ovulation. The results also showed the differences in gene products between treated and untreated samples, suggesting that IGF-1 plays an important role regarding ovulation. / Studier med hjälp av den selektiva insulinlika tillväxtfaktor 1 receptorn (IGF-1R) antagonisten; picropodof?phyllin (PPP), hur samspelet mellan livmoderslemhinnan och implantationsprocessen, samt hur ovulationen påverkas av insulinlika tillväxtfaktorn 1 (IGF-1) kan nu utföras. IGF-1 tros ha en viktig roll för den reproduktiva processen, där den påverkar ovulation, implantation och embryoutveckling. IGF-familjen består av tre ligander; insulin, IGF-1 och IGF-2. IGF transporteras bundet till bindarprotein (IGFBP). Medlemmarna i IGF receptorfamiljen kan binda IGF-1, IGF-2 och insulin fast med olika affinitet. PPP som är en cykloligan, är en analog från podofyllotoxin och fungerar som en syntetisk IGF-1 receptorantagonist, som selektivt inhiberar receptorns aktivitet. PPP tros även kunna nedreglera genexpression av receptorn. Tre tidigare projektarbeten har utförts på vävnader från möss injicerade med PPP. Tyngdpunkterna i dessa arbeten har legat på immunhistokemiska studier av IGF-1 i reproduktionsorgan från möss, uttryck av IGF-1, dess receptor och bindarprotein 1 i ovarier och uterus efter behandling med PPP. I denna studie användes vävnad samt cDNA från sju möss behandlade med PPP, i olika stadier av reproduktionen samt även icke behandlade möss. Studiens syfte var att med sanntids-PCR jämföra genuttryck från östrogenreceptor α och β, progesteronreceptor A och B, tillväxthormonreceptor, Interleukin 1 α och β, ’tumor necrosis’ faktor α samt androgenreceptor i vävnad från PPP-behandlade och obehandlade möss och genom de erhållna resultaten från ovarievävnaden utläsa effekten på ovulationen och från uterusvävnaden effekten på implantation och receptivitet. Studieresultaten visade att IGF-1s frånvaro gav förändrade nivåer av genprodukter, som medförde minskad ovulationen. Studien visade att IGF-1s roll vid ovulationen var väsentlig.
53

Characterization of Atrial Natriuretic Factor Storage Pools in HL-1 Atrial Cardiomyocytes

Choudhry, Asna Ali 04 August 2011 (has links)
Atrial natriuretic factor (ANF) is a cardiac hormone that helps maintain cardiovascular homeostasis. ANF secretion is linked to the constitutive, regulated and constitutive-like pathways. Presence of a monensin-sensitive pool that may follow constitutive-like secretion has previously been identified in an isolated atrial perfusion study. The intracellular ANF storage pools linked to each secretory pathway have not been identified. In this study, ANF storage and secretion was characterized in HL-1 atrial cardiomyocytes through the use of pharmacological agents, density gradient and RP- HPLC analysis. Treatment of HL-1 cells with monensin followed by cell fractionation was unsuccessful in identifying the monensin-sensitive pool. RP-HPLC analysis identified presence of low molecular weight ANF in low density gradient fractions that were defined by the presence of organelle markers of Golgi, early endosome, clathrin and corin. Since the monensin-sensitive pool was thought to be of a constitutive-like nature, targeting this pathway with pharmacological inhibitors of clathrin coat vesicle (CCV) formation and endosomal trafficking failed to prevent stimuli-independent secretion. Based on an inability to prevent ANF secretion by targeting the constitutive-like pathway and the presence of low molecular weight ANF in low density gradient fractions, stimuli- independent ANF secretion seems to be through a constitutive pathway.
54

CLCA : chloride channel or modulator?

Loewen, Matthew Eric 14 April 2004
A CLCA protein (CL for chloride channel and CA for calcium) cloned from porcine ileum was expressed and characterized. The regulatory behavior, inhibitor sensitivity, and functional properties of chloride conductance associated with the expression of pCLCA1 cDNA were investigated in non-epithelial NIH/3T3 fibroblasts and in an epithelial Caco-2 cell line. These properties were also investigated in freshly isolated retinal pigment epithelial (RPE) cells and in primary cultures of these cells which express an endogenous cCLCA1. In NIH/3T3 fibroblasts, the chloride efflux induced by pCLCA1 was directly activated by calcium. A and C kinase agonists were without effect. The electrogenic nature of chloride efflux was confirmed by detection of outwardly rectified chloride currents. Selected anion channel blockers inhibited both the pCLCA1 agonist-induced current and chloride efflux. The inhibitors also reduced Ussing chamber short circuit current and chloride efflux from primary RPE cultures. However, these same agents did not inhibit chloride efflux in fibroblasts expressing the cystic fibrosis transmembrane regulator (CFTR) conductive chloride channel. The expression of pCLCA1 increased cAMP/A kinase-dependent chloride ion release from fibroblasts and Caco-2 cells expressing CFTR. These pleiotropic effects of CLCA protein expression suggested that the protein may regulate the activity of chloride conductance, rather than functioning as a primary ion transporter. This putative regulatory behavior was further investigated in Caco-2 cells. The rate of 36Cl efflux and the amplitude of currents in patch clamp studies after activation of A kinase or intracellular Ca2+ mobilization was significantly increased in freshly passaged Caco-2 cells expressing pCLCA1. However, 36Cl efflux and short circuit Ussing chamber studies in polarized Caco-2 cells provided evidence that both endogenous and pCLCA1-dependent Ca2+-sensitive chloride conductance were lost from 14 day post-passage cells. cAMP-dependent chloride conductance continued to be modulated by pCLCA1 expression in differentiated 14 day post-passage Caco-2 cells, demonstrating the retention of pCLCA1 effects in these mature cells. We conclude that pCLCA1 expression enhances the sensitivity of endogenous chloride channels to both natural agonists, Ca2+and cAMP, but that it lacks inherent Ca2+-dependent chloride channel activity.
55

CLCA : chloride channel or modulator?

Loewen, Matthew Eric 14 April 2004 (has links)
A CLCA protein (CL for chloride channel and CA for calcium) cloned from porcine ileum was expressed and characterized. The regulatory behavior, inhibitor sensitivity, and functional properties of chloride conductance associated with the expression of pCLCA1 cDNA were investigated in non-epithelial NIH/3T3 fibroblasts and in an epithelial Caco-2 cell line. These properties were also investigated in freshly isolated retinal pigment epithelial (RPE) cells and in primary cultures of these cells which express an endogenous cCLCA1. In NIH/3T3 fibroblasts, the chloride efflux induced by pCLCA1 was directly activated by calcium. A and C kinase agonists were without effect. The electrogenic nature of chloride efflux was confirmed by detection of outwardly rectified chloride currents. Selected anion channel blockers inhibited both the pCLCA1 agonist-induced current and chloride efflux. The inhibitors also reduced Ussing chamber short circuit current and chloride efflux from primary RPE cultures. However, these same agents did not inhibit chloride efflux in fibroblasts expressing the cystic fibrosis transmembrane regulator (CFTR) conductive chloride channel. The expression of pCLCA1 increased cAMP/A kinase-dependent chloride ion release from fibroblasts and Caco-2 cells expressing CFTR. These pleiotropic effects of CLCA protein expression suggested that the protein may regulate the activity of chloride conductance, rather than functioning as a primary ion transporter. This putative regulatory behavior was further investigated in Caco-2 cells. The rate of 36Cl efflux and the amplitude of currents in patch clamp studies after activation of A kinase or intracellular Ca2+ mobilization was significantly increased in freshly passaged Caco-2 cells expressing pCLCA1. However, 36Cl efflux and short circuit Ussing chamber studies in polarized Caco-2 cells provided evidence that both endogenous and pCLCA1-dependent Ca2+-sensitive chloride conductance were lost from 14 day post-passage cells. cAMP-dependent chloride conductance continued to be modulated by pCLCA1 expression in differentiated 14 day post-passage Caco-2 cells, demonstrating the retention of pCLCA1 effects in these mature cells. We conclude that pCLCA1 expression enhances the sensitivity of endogenous chloride channels to both natural agonists, Ca2+and cAMP, but that it lacks inherent Ca2+-dependent chloride channel activity.
56

Characterization of Atrial Natriuretic Factor Storage Pools in HL-1 Atrial Cardiomyocytes

Choudhry, Asna Ali 04 August 2011 (has links)
Atrial natriuretic factor (ANF) is a cardiac hormone that helps maintain cardiovascular homeostasis. ANF secretion is linked to the constitutive, regulated and constitutive-like pathways. Presence of a monensin-sensitive pool that may follow constitutive-like secretion has previously been identified in an isolated atrial perfusion study. The intracellular ANF storage pools linked to each secretory pathway have not been identified. In this study, ANF storage and secretion was characterized in HL-1 atrial cardiomyocytes through the use of pharmacological agents, density gradient and RP- HPLC analysis. Treatment of HL-1 cells with monensin followed by cell fractionation was unsuccessful in identifying the monensin-sensitive pool. RP-HPLC analysis identified presence of low molecular weight ANF in low density gradient fractions that were defined by the presence of organelle markers of Golgi, early endosome, clathrin and corin. Since the monensin-sensitive pool was thought to be of a constitutive-like nature, targeting this pathway with pharmacological inhibitors of clathrin coat vesicle (CCV) formation and endosomal trafficking failed to prevent stimuli-independent secretion. Based on an inability to prevent ANF secretion by targeting the constitutive-like pathway and the presence of low molecular weight ANF in low density gradient fractions, stimuli- independent ANF secretion seems to be through a constitutive pathway.
57

Molecular mechanisms of brain derived neurotrophic factor secretion and action /

Gunther, Erik Christian. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 106-118).
58

Development of a dna vaccine against _streptococcus mutans_: A novel approach to immunization against dental caries

Han, Thomas 01 June 2005 (has links)
Streptococcus mutans is the main causative agent of dental caries, which is a widespread infectious disease. A number of surface molecules are involved in the pathogenicity of this organism, including adherence and aggregation factors. The wall-associated protein A (WapA) of Streptococcus mutans GS-5 was previously demonstrated to be a sucrose-dependent adherence and aggregation factor, and is a larger precursor to extracellular antigen A (AgA), a candidate antigen for a dental caries vaccine.The full-length wapA gene and a C-terminal truncated version agA encoding the AgA were cloned into the mammalian expression vector pcDNA 3.1/V5/His-TOPO. The above constructs were mixed with a cationic lipid and used to transfect Chinese hamster ovary (CHO) cells. Transient expression of the wapA and agA genes was observed at 24 h post-transfection, as shown by Western immunoblot analysis. In CHO, cells WapA containing the membrane and wall-spanning region was found in apoptotic bodies, whereas the soluble AgA, which lacked the hydrophobic region, was found in extracellular medium. A higher salivary IgA level was observed in mice immunized with the pcDNA-wapA vaccine as compared to those immunized with the pcDNA-agA vaccine. Furthermore, the anti-WapA antibody inhibited S. mutans sucrose-dependent adherence, suggesting potential protection of the tooth against S. mutans colonization, while anti-AgA had no significant effect. Indeed, prediction and analysis of protein epitopes showed that WapA contains highly promiscuous MHC-II binding motifs that are absent from AgA. Immunodot assay confirmed that WapA bound biotin-labeled dextran, whereas AgA did not.
59

INHIBITORY PROPERTIES OF <i>MICROPLITIS CROCEIPES</i> TERATOCYTE SECRETORY PRODUCTS AND THE RECOMBINANT PROTEIN TSP14 ON PROTEIN SYNTHESIS

DiLuna, Francis Anthony 01 January 2003 (has links)
Microplitis croceipes is a solitary endoparasitic wasp that oviposits in the hemocoel of Heleothis virescens larvae. Upon parasitization, the host larvaes physiology is altered; resulting in a compromised immune system and a decrease in the production of some vital proteins resulting in a terminal post-wandering prepupal state. Teratocytes, cells derived from the extraembryonic serosa of the parasitic wasp, mimic symptoms of parasitization when injected into host larvae, independent of other factors like polydnavirus and venom. Some of the inhibition of protein synthesis can be attributed to proteins secreted by the teratocytes (teratocyte secretory proteins or TSP). A fraction of TSP between 330 kDa inhibits protein synthesis in vivo, in the in vitro fat body and testes assays, and in the rabbit reticulocyte lysate and wheat germ extract assays. This fraction, however, has no effect on nucleic acid synthesis. Its effect on protein synthesis is dose dependent and exposure time sensitive. A 13.9 kDa protein isolated from TSP and expressed in a baculovirus system seems primarily responsible for the inhibition. Although TSP14 production was low, it did bind to the cell surface, enter the cell, and inhibit protein synthesis as the 330 kDa factor did.
60

Characterization of Atrial Natriuretic Factor Storage Pools in HL-1 Atrial Cardiomyocytes

Choudhry, Asna Ali 04 August 2011 (has links)
Atrial natriuretic factor (ANF) is a cardiac hormone that helps maintain cardiovascular homeostasis. ANF secretion is linked to the constitutive, regulated and constitutive-like pathways. Presence of a monensin-sensitive pool that may follow constitutive-like secretion has previously been identified in an isolated atrial perfusion study. The intracellular ANF storage pools linked to each secretory pathway have not been identified. In this study, ANF storage and secretion was characterized in HL-1 atrial cardiomyocytes through the use of pharmacological agents, density gradient and RP- HPLC analysis. Treatment of HL-1 cells with monensin followed by cell fractionation was unsuccessful in identifying the monensin-sensitive pool. RP-HPLC analysis identified presence of low molecular weight ANF in low density gradient fractions that were defined by the presence of organelle markers of Golgi, early endosome, clathrin and corin. Since the monensin-sensitive pool was thought to be of a constitutive-like nature, targeting this pathway with pharmacological inhibitors of clathrin coat vesicle (CCV) formation and endosomal trafficking failed to prevent stimuli-independent secretion. Based on an inability to prevent ANF secretion by targeting the constitutive-like pathway and the presence of low molecular weight ANF in low density gradient fractions, stimuli- independent ANF secretion seems to be through a constitutive pathway.

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