957 resultados para Austin, Stephen F. (Stephen Fuller), 1793-1836.


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The man to whom the letter is addressed is Francis Leigh Walsh who was a land surveyor and registrar. Mr. Walsh was born on March 12, 1789 in Harford County, Maryland to Thomas Welsh, a United Empire Loyalist. In 1793, his family moved to Norfolk County and in 1810, Francis succeeded his father as registrar for Norfolk County. During the War of 1812 he served in the local militia and became a captain in 1824. He was the representative for Norfolk in the legislative assembly of Upper Canada from 1820 to 1828 and 1834 to 1836. He became justice of the peace in the London district in 1821 and 1838 in the Talbot district. He died in Simcoe on Oct. 14th, 1884. His son, Aquila Walsh served in the Legislative Assembly of the Province of Canada and in the Canadian House of Commons. Benjamin Hardison was born in Berwick in the Thirteen Colonies (British colonies on the Atlantic Coast of North America) on April 2, 1757 to Thomas Hardison and Mary Chadbourne. He was a farmer, miller and political figure. He was the representative for 4th Lincoln and Norfolk in the Legislative Assembly of Upper Canada from 1797-1800. On January 21, 1800 he married Jane Warren. He served with the American forces during the American Revolution at which time he was taken prisoner and sent to Canada. Later, he settled in Fort Erie where he was a captain in the militia and a justice of the peace for the Niagara district. He operated mills and a distillery in Fort Erie and died there on July 26, 1823. Source: http://en.vionto.com/show/me/Francis+Leigh+Walsh http://en.wikipedia.org/wiki/Benjamin_Hardison

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Benjamin Rathburn (1790-1873) was a builder, banker and hotel-keeper who was well-known for his work in the development and expansion of Buffalo in the 1830s. He also conducted business in the Village of Niagara Falls. He purchased large tracts of land (largely on credit) with the intent to sell the land at a profit. However, the sales did not meet his expectations and Rathburn found himself over-extended on credit, ultimately leading to his financial ruin.Jesse P. Haines (1793-1877) was an American cartographer who is credited with mapping the Villages of Lockport and Niagara Falls, New York.

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Benjamin Rathburn (1790-1873) was a builder, banker and hotel-keeper who was well-known for his work in the development and expansion of Buffalo in the 1830s. He also conducted business in the Village of Niagara Falls. He purchased large tracts of land (largely on credit) with the intent to sell the land at a profit. However, the sales did not meet his expectations and Rathburn found himself over-extended on credit, ultimately leading to his financial ruin. Jesse P. Haines (1793-1877) was an American cartographer who is credited with mapping the Villages of Lockport and Niagara Falls, New York.

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La quantité de données générée dans le cadre d'étude à grande échelle du réseau d'interaction protéine-protéine dépasse notre capacité à les analyser et à comprendre leur sens; d'une part, par leur complexité et leur volume, et d'un autre part, par la qualité du jeu de donnée produit qui semble bondé de faux positifs et de faux négatifs. Cette dissertation décrit une nouvelle méthode de criblage des interactions physique entre protéines à haut débit chez Saccharomyces cerevisiae, la complémentation de fragments protéiques (PCA). Cette approche est accomplie dans des cellules intactes dans les conditions natives des protéines; sous leur promoteur endogène et dans le respect des contextes de modifications post-traductionnelles et de localisations subcellulaires. Une application biologique de cette méthode a permis de démontrer la capacité de ce système rapporteur à répondre aux questions d'adaptation cellulaire à des stress, comme la famine en nutriments et un traitement à une drogue. Dans le premier chapitre de cette dissertation, nous avons présenté un criblage des paires d'interactions entre les protéines résultant des quelques 6000 cadres de lecture de Saccharomyces cerevisiae. Nous avons identifié 2770 interactions entre 1124 protéines. Nous avons estimé la qualité de notre criblage en le comparant à d'autres banques d'interaction. Nous avons réalisé que la majorité de nos interactions sont nouvelles, alors que le chevauchement avec les données des autres méthodes est large. Nous avons pris cette opportunité pour caractériser les facteurs déterminants dans la détection d'une interaction par PCA. Nous avons remarqué que notre approche est sous une contrainte stérique provenant de la nécessité des fragments rapporteurs à pouvoir se rejoindre dans l'espace cellulaire afin de récupérer l'activité observable de la sonde d'interaction. L'intégration de nos résultats aux connaissances des dynamiques de régulations génétiques et des modifications protéiques nous dirigera vers une meilleure compréhension des processus cellulaires complexes orchestrés aux niveaux moléculaires et structuraux dans les cellules vivantes. Nous avons appliqué notre méthode aux réarrangements dynamiques opérant durant l'adaptation de la cellule à des stress, comme la famine en nutriments et le traitement à une drogue. Cette investigation fait le détail de notre second chapitre. Nous avons déterminé de cette manière que l'équilibre entre les formes phosphorylées et déphosphorylées de l'arginine méthyltrans©rase de Saccharomyces cerevisiae, Hmt1, régulait du même coup sont assemblage en hexamère et son activité enzymatique. L'activité d'Hmt1 a directement un impact dans la progression du cycle cellulaire durant un stress, stabilisant les transcrits de CLB2 et permettant la synthèse de Cln3p. Nous avons utilisé notre criblage afin de déterminer les régulateurs de la phosphorylation d'Hmt1 dans un contexte de traitement à la rapamycin, un inhibiteur de la kinase cible de la rapamycin (TOR). Nous avons identifié la sous-unité catalytique de la phosphatase PP2a, Pph22, activé par l'inhibition de la kinase TOR et la kinase Dbf2, activé durant l'entrée en mitose de la cellule, comme la phosphatase et la kinase responsable de la modification d'Hmt1 et de ses fonctions de régulations dans le cycle cellulaire. Cette approche peut être généralisée afin d'identifier et de lier mécanistiquement les gènes, incluant ceux n'ayant aucune fonction connue, à tout processus cellulaire, comme les mécanismes régulant l'ARNm.

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La sigla LGBT se puede comprender como una articulación de elementos discursivos sobre el género y la sexualidad. En Colombia, dicha categoría se ha desarrollado en buena medida de parte de los movimientos sociales. El objetivo central del trabajo de grado es analizar algunos significados sobre el género y la sexualidad que se articulan bajo dicho significante, reconociendo que no son unívocos y que a un mismo significante se le pueden atribuir significados que pueden llegar a ser incluso contradictorios. Para esto, analicé cómo a partir de algunas formas de acción colectiva se han articulado distintos entendimientos del género y la sexualidad como campos de subjetivación. El primer capítulo consiste en un repaso histórico por algunos movimientos sociales de género y sexualidad en Colombia, valiéndome de fuentes secundarias. La segunda y la tercera presentan relatos individuales y grupales de dos organizaciones en Bogotá: el Colectivo León Zuleta y la Colectiva Lobas Furiosas. A partir de entrevistas semi-estructuradas con integrantes de cada colectivo, examiné cómo algunos de los significados construidos colectivamente sobre el género y la sexualidad de acercan a algunos significados articulados bajo la categoría LGBT, pero cómo otros también se alejan, tensionan o cuestionan.

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Esta investigación se centra en la ©dération Internationale de Football Association (FIFA) como organización política. Intenta responder dos interrogantes primordiales: 1) ¿cómo la FIFA ha constituido el poder que tiene actualmente y, así, hacerse del monopolio indiscutido del ºtbol? Y 2) ¿cómo ha cambiado en el tiempo la política interna de FIFA y su vínculo con la política internacional? Para lograr esto, se realiza un estudio histórico, basado principalmente en documentos, que intenta caracterizar y analizar los cambios de la organización en el tiempo. Se enfatizan las últimas dos presidencias de FIFA, de João Havelange y Joseph Blatter, como casos de estudio.

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Background: Endothelin-1 stimulates Gq protein-coupled receptors to promote proliferation in dividing cells or hypertrophy in terminally differentiated cardiomyocytes. In cardiomyocytes, endothelin-1 rapidly (within minutes) stimulates protein kinase signaling, including extracellular-signal regulated kinases 1/2 (ERK1/2; though not ERK5), with phenotypic/physiological changes developing from approximately 12 h. Hypertrophy is associated with changes in mRNA/protein expression, presumably consequent to protein kinase signaling, but the connections between early, transient signaling events and developed hypertrophy are unknown. Results: Using microarrays, we defined the early transcriptional responses of neonatal rat cardiomyocytes to endothelin-1 over 4 h, differentiating between immediate early gene (IEG) and second phase RNAs with cycloheximide. IEGs exhibited differential temporal and transient regulation, with expression of second phase RNAs within 1 h. Of transcripts upregulated at 30 minutes encoding established proteins, 28 were inhibited >50% by U0126 (which inhibits ERK1/2/5 signaling), with 9 inhibited 25-50%. Expression of only four transcripts was not inhibited. At 1 h, most RNAs (approximately 67%) were equally changed in total and polysomal RNA with approximately 17% of transcripts increased to a greater extent in polysomes. Thus, changes in expression of most protein-coding RNAs should be reflected in protein synthesis. However, approximately 16% of transcripts were essentially excluded from the polysomes, including some protein-coding mRNAs, presumably inefficiently translated. Conclusion: The phasic, temporal regulation of early transcriptional responses induced by endothelin-1 in cardiomyocytes indicates that, even in terminally differentiated cells, signals are propagated beyond the primary signaling pathways through transcriptional networks leading to phenotypic changes (that is, hypertrophy). Furthermore, ERK1/2 signaling plays a major role in this response.

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ERK1 and ERK2 (ERK1/2) are central to the regulation of cell division, growth and survival. They are activated by phosphorylation of the Thr- and the Tyr- residues in their Thr-Glu-Tyr activation loops. The dogma is that dually-phosphorylated ERK1/2 constitute the principal activities in intact cells. We previously showed that, in neonatal rat cardiac myocytes, endothelin-1 and phorbol 12-myristate 13-acetate (PMA) powerfully and rapidly (maximal at ~ 5 min) activate ERK1/2. Here, we show that dually-phosphorylated ERK1/2 rapidly (< 2 min) appear in the nucleus following stimulation with endothelin-1. We characterized the active ERK1/2 species in myocytes exposed to endothelin-1 or PMA using MonoQ FPLC. Unexpectedly, two peaks of ERK1 and two peaks of ERK2 activity were resolved using in vitro kinase assays. One of each of these represented the dually-phosphorylated species. The other two represented activities for ERK1 or ERK2 which were phosphorylated solely on the Thr- residue. Monophosphothreonyl ERK1/2 represented maximally ~ 30% of total ERK1/2 activity after stimulation with endothelin-1 or PMA, and their kcat values were estimated to be minimally ~ 30% of the dually-phosphorylated species. Appearance of monophosphothreonyl ERK1/2 was rapid but delayed in comparison with dually-phosphorylated ERK1/2. Of 10 agonists studied, endothelin-1 and PMA were most effective in terms of ERK1/2 activation and in stimulating the appearance of monophosphothreonyl and dually-phosphorylated ERK1/2. Thus, enzymically active monophosphothreonyl ERK1/2 are formed endogenously following activation of the ERK1/2 cascade and we suggest that monophosphothreonyl ERK1/2 arise by protein tyrosine phosphatase-mediated dephosphorylation of dually-phosphorylated ERK1/2.

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The nuclear Dbf2-related protein kinases 1 and 2 (NDR1/2) are closely-related AGC family kinases that are strongly conserved through evolution. In mammals, they are activated inter alia by phosphorylation of an hydrophobic domain threonine-residue [NDR1(Thr-444)/NDR2(Thr-442)] by an extrinsic protein kinase followed by autophosphorylation of a catalytic domain serine-residue [NDR1(Ser-281)/NDR2(Ser-282)]. We examined NDR1/2 expression and regulation in primary cultures of neonatal rat cardiac myocytes and in perfused adult rat hearts. In myocytes, transcripts for NDR2, but not NDR1, were induced by the hypertrophic agonist, endothelin-1. NDR1(Thr-444) and NDR2(Thr-442) were rapidly phosphorylated (maximal in 15-30 min) in myocytes exposed to some phosphoprotein Ser-/Thr-phosphatase 1/2 inhibitors (calyculin A, okadaic acid) and, to a lesser extent, by hyperosmotic shock, low concentrations of H(2)O(2), or chelerythrine. In myocytes adenovirally-transduced to express FLAG-NDR2 (which exhibited a mainly-cytoplasmic localisation), the same agents increased FLAG-NDR2 activity as assessed by in vitro protein kinase assays, indicative of FLAG-NDR2(Ser-282/Thr-442) phosphorylation. Calyculin A-induced phosphorylation of NDR1(Thr-444)/NDR2(Thr-442) and activation of FLAG-NDR2 were inhibited by staurosporine, but not by other protein kinase inhibitors tested. In ex vivo rat hearts, NDR1(Thr-444)/NDR2(Thr-442) were phosphorylated in response to ischaemia-reperfusion or calyculin A. From a pathological viewpoint, we conclude that activities of NDR1 and NDR2 are responsive to cytotoxic stresses in heart preparations and this may represent a previously-unidentified response to myocardial ischaemia in vivo.

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Inhibition of glycogen synthase kinase 3β (GSK3β) as a consequence of its phosphorylation by protein kinase B/Akt (PKB/Akt) has been implicated in cardiac myocyte hypertrophy in response to endothelin-1 or phenylephrine. We examined the regulation of GSK3α (which we show to constitute a significant proportion of the myocyte GSK3 pool) and GSK3β in cardiac myocytes. Although endothelin increases phosphorylation of GSK3 and decreases its activity, the response is less than that induced by insulin (which does not promote cardiac myocyte hypertrophy). GSK3 phosphorylation induced by endothelin requires signalling through the extracellular signal-regulated kinase 1/2 (ERK1/2) cascade and not the PKB/Akt pathway, whereas the reverse is true for insulin. Cardiac myocyte hypertrophy involves changes in morphology, and in gene and protein expression. The potent GSK3 inhibitor 1-azakenpaullone increases myocyte area as a consequence of increased cell length whereas phenylephrine increases both length and width. Azakenpaullone or insulin promotes AP1 transcription factor binding to an AP1 consensus oligonucleotide, but this was significantly less than that induced by endothelin and derived principally from increased binding of JunB protein, the expression of which was increased. Azakenpaullone promotes significant changes in gene expression (assessed by Affymetrix microarrays), but the overall response is less than with endothelin and there is little overlap between the genes identified. Thus, although GSK3 may contribute to cardiac myocyte hypertrophy in some respects (and presumably plays an important role in myocyte metabolism), it does not appear to contribute as significantly to the response induced by endothelin as has been maintained.

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The canonical pathway of regulation of the germinal centre kinase (GCK) III subgroup member, mammalian Sterile20-related kinase 3 (MST3), involves a caspase-mediated cleavage between N-terminal catalytic and C-terminal regulatory domains with possible concurrent autophosphorylation of the activation loop MST3(Thr178-), induction of Ser-/Thr-protein kinase activity and nuclear localisation. We identified an alternative ‘non-canonical’ pathway of MST3 activation (regulated primarily through dephosphorylation) which may also be applicable to other GCKIII (and GCKVI) subgroup members. In the basal state, inactive MST3 co-immunoprecipitated with the Golgi protein, GOLGA2/gm130. Activation of MST3 by calyculin A (a protein Ser-/Thr- phosphatase 1/2A inhibitor) stimulated (auto)phosphorylation of MST3(Thr178-) in the catalytic domain with essentially simultaneous cis-autophosphorylation of MST3(Thr328-) in the regulatory domain, an event also requiring the MST3(341-376) sequence which acts as a putative docking domain. MST3(Thr178-) phosphorylation increased MST3 kinase activity but this activity was independent of MST3(Thr328-) phosphorylation. Interestingly, MST3(Thr328-) lies immediately C-terminal to a STRAD pseudokinase-like site recently identified as being involved in binding of GCKIII/GCKVI members to MO25 scaffolding proteins. MST3(Thr178- /Thr328-) phosphorylation was concurrent with dissociation of MST3 from GOLGA2/gm130 and association of MST3 with MO25, and MST3(Thr328-) phosphorylation was necessary for formation of the activated MST3-MO25 holocomplex.

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Endothelin-1 promotes cardiomyocyte hypertrophy by inducing changes in gene expression. Immediate early genes including activating transcription factor 3 (Atf3), Egr1 and Ptgs2 are rapidly and transiently upregulated by endothelin-1 in cardiomyocytes. Atf3 regulates expression of downstream genes and is implicated in negative feedback regulation of other immediate early genes. To identify Atf3-regulated genes, we knocked down Atf3 expression in cardiomyocytes exposed to endothelin-1 and used microarrays to interrogate the transcriptomic effects. Of upregulated mRNAs, expression of 23 (including Egr1, Ptgs2) was enhanced and expression of 25 was inhibited by Atf3 knockdown. Using quantitative PCR, we determined that knockdown of Atf3 had little effect on upregulation of Egr1 mRNA over 30 min, but abolished the subsequent decline, causing sustained Egr1 mRNA expression and enhanced protein expression. This resulted from direct binding of Atf3 to the Egr1 promoter. Mathematical modelling established that Atf3 can suffice to suppress Egr1 expression. Given the widespread co-regulation of Atf3 with Egr1, we suggest that the Atf3-Egr1 negative feedback loop is of general significance. Loss of Atf3 caused abnormal cardiomyocyte growth, presumably resulting from dysregulation of target genes. Our data therefore identify Atf3 as a nexus in cardiomyocyte hypertrophy required to facilitate the full and proper growth response.