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(40)Ar/(39)Ar ages and Sr-Nd-Pb-Os geochemistry of CAMP tholeiites from Western Maranhao basin (NE Brazil)

MERLE, Renaud; MARZOLI, Andrea; BERTRAND, Herve; REISBERG, Laurie; VERATI, Chrystele; ZIMMERMANN, Catherine; CHIARADIA, Massimo; BELLIENI, Giuliano; ERNESTO, Marcia
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.72%
The Central Atlantic Magmatic Province (CAMP), emplaced at the Triassic-Jurassic (T-J) boundary (-200 Ma), is among the largest igneous provinces on Earth. The Maranhao basin in NE Brazil is located around 700 km inland and 2000 km from the site of the earliest Pangea disruption. The CAMP tholeiites occur only in the western part of the basin and have been described as low and high-Ti. Here we document the occurrence of two sub-groups among the high-Ti tholeiites in the Western Maranhao basin. The major and trace elements and the Sr-Nd-Pb isotopic ratios define three chemical groups corresponding to the low-Ti (TiO(2)< 1.3 wt.%), high-Ti (TiO(2)-2.0 wt.%) and evolved high-Ti (TiO(2 >)3 wt.%) western Maranhao basin tholeiites (WMBT). The new (40)Ar/(39)Ar plateau ages obtained on plagioclase separates for high-Ti (199.7 +/- 2.4 Ma) and evolved high-Ti WMBT (197.2 +/- 0.5 Ma and 198.2 +/- 0.6 Ma) are indistinguishable and identical to those of previously analyzed low-Ti WMBT (198.5 +/- 0.8 Ma) and to the mean (40)Ar/(39)Ar age of the CAMP (199 +/- 2.4 Ma). We also present the first Re-Os isotopic data for CAMP basalts. The low and high-Ti samples display mantle-like initial ((187)Os/(188)Os)(i) ranging from 0.1267 to 0.1299, while the evolved high-Ti samples are more radiogenic (((187)Os/ (188)Os)(i) up to 0.184) We propose that the high-Ti WMBT were derived from the sub-lithospheric asthenosphere...

Paleo- and rock magnetism of the Central Atlantic Magmatic Province (CAMP) from Portugal: global-scale correlations and implications for the paleogeography of Iberia at 200 Ma

Fernandes, Susana de Lurdes Alves
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2013 ENG
Relevância na Pesquisa
36.83%
Tese de mestrado em Ciências Geofísicas, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2013; A Província Magmática do Atlântico Central (CAMP) é considerada uma das maiores províncias ígneas do Fanerozóico e é contemporânea da crise biológica que marca a transição Triássico-Jurássico (Tr-J) (~200 Ma). Vestígios desta província são encontrados em quatro continentes com uma área que excede os 100 milhões de km2, o que leva muitos cientistas a acreditar que a crise biológica que marca este período é provocada pela erupção desta província magmática. Neste sentido, as lavas da CAMP têm sido extensivamente estudadas, especialmente nos Estados Unidos e em Marrocos, não só para perceber o seu sincronismo com a crise biológica, mas também para estudos de paleoreconstituição usando métodos paleomagneticos. Em Portugal as evidências da CAMP são representadas por um dique de cerca de 540 Km de extensão, o dique da Messejana, e por afloramentos de lavas continentais distribuídos ao longo das bacias do Algarve e de Santiago do Cacém. A importância do estudo destas lavas recai sobretudo na necessidade de calcular novos polos paleomagneticos para reconstituir a paleogeografia da placa Ibérica à 200 Ma...

cAMP enables rapid conduction of action potentials in the Locusta migratoria DCMD neuron

Hamour, Amr
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
36.75%
Neurons endure a variety of environmental stressors that have many implications for proper functioning. By studying how energetic constraints, in the form of hypoxia, impact neuronal function in the locust, a cellular mechanism for maintaining neuronal performance under such stress can be determined. Using the locust’s costly DCMD predator avoidance neuron, the role of cAMP and octopamine in preserving conduction velocity was examined. Under normoxic conditions, cAMP depletion led to a significant decrease in relative conduction velocity for all action potential frequencies. Under hypoxic conditions, the administration of cAMP stabilized relative conduction velocities for all action potential frequencies. The depletion of cAMP levels prevented the protection of relative conduction velocity mediated by octopamine. At very high frequencies (>300 Hz), the effect of decreasing cAMP levels was exacerbated, resulting in the loss of capacity to sustain such high frequency firing. I propose that cAMP is critical in enabling rapid conduction of action potentials in the locust central nervous system, and further, that cAMP mediates the protective effect of octopamine.

Souvenir of Niagara Camp

Cameron, Chantal
Fonte: Brock University Publicador: Brock University
Tipo: Outros
EN
Relevância na Pesquisa
36.8%
Camp Niagara, in Niagara-on-the-Lake, Ontario, was used as summer training grounds for the Second Division of the Canadian Expeditionary Force at the start of World War I in 1914. In 1917, the Camp was used to train a group of expatriate Poles and Polish Americans who were recruited to serve in the war. Over 22, 000 volunteers of the Polish diaspora from across Canada and the United States trained at Camp Niagara, known to them as Camp Kosciuszko.; A booklet entitled Souvenir of Niagara Camp: Niagara-on-the-Lake, Canada, featuring post cards with images of Niagara Camp and Fort Mississauga during World War I. There are 16 black and white post cards included. Most of the images are of overseas forces at Camp Niagara. Other images include the Governor General and Headquarter staff at Camp Niagara, Fort George Hospital, Battalion Camp at Fort Mississauga, and Premier Borden reviewing Overseas Forces at Camp Niagara. The booklet is published by F.H. Leslie Limited, Publisher, Niagara Falls.

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Trench and camp; Camp Johnston trench and camp; Trench and camp (Camp Johnston, Jacksonville, Fla.)

National War Work Council, Y.M.C.A. of the United States
Fonte: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla ) Publicador: Florida Times-Union; Florida Times-Union ( Camp Johnston, Jacksonville, Fla )
Tipo: Artigo de Revista Científica
ENGLISH
Relevância na Pesquisa
36.69%
(Dates or Sequential Designation) Vol. 1, no. 1 (Jan. 5, 1918)-v. 2, no. 3 (Jan. 16, 1919).; "Camp Johnston" appears above masthead title, .; Published under the auspices of National War Work Council, Y.M.C.A. of the United States.; "Printed weekly for the Y.M.C.A. by courtesy of the Florida Times-Union."; "Army news for Army men and their home folks."

Effect of dibutyryl cAMP on the cAMP content, meiotic progression, and developmental potential of in vitro matured pre-pubertal and adult pig oocytes

Bagg, M.; Nottle, M.; Grupen, C.; Armstrong, D.
Fonte: Wiley-Liss Publicador: Wiley-Liss
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
Relevância na Pesquisa
36.75%
Pre-pubertal pig oocytes display reduced developmental competence compared with adult oocytes following in vitro maturation (IVM). Exposure to dibutyryl cyclic adenosine monophosphate (dbcAMP) for the first 20 hr IVM improves development of pre-pubertal oocytes, suggesting that their cAMP content may be inadequate. This study examined the effect of 1 mM dbcAMP treatment for the first 22 hr of IVM on the cAMP content, meiotic progression, and embryo development of pre-pubertal and adult oocytes. In control groups, a two-fold increase in cAMP was observed in adult oocytes after 22 hr IVM, with no change in pre-pubertal oocyte cAMP content. At 22 hr IVM, dbcAMP treatment resulted in two- and five-fold increases in pre-pubertal and adult oocyte cAMP, respectively. After 22 hr control IVM, a greater proportion of pre-pubertal oocytes occupied metaphase I (MI) compared with adult oocytes (69% vs. 49%). dbcAMP treatment reduced the proportion of pre-pubertal and adult oocytes in MI stage at 22 hr. Despite dbcAMP treatment, the proportion of pre-pubertal oocytes in the MI stage at 22 hr remained higher than that of adult oocytes. In control groups, adult oocytes displayed a greater ability to form blastocysts compared with pre-pubertal oocytes following either parthenogenetic activation (59% vs. 25%) or in vitro fertilization (IVF) (47% vs. 19%). dbcAMP treatment increased subsequent blastocyst formation rates of pre-pubertal oocytes...

Einfluss des Kofaktors NAD+/NADH auf die cAMP-Bindung an der S-Adenosyl-L-Homocystein-Hydrolase; Influence of the cofactor NAD+/NADH on the binding of cAMP to S-adenosyl-homocysteine hydrolase

Kirschler, Julia Nina
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
36.9%
Das Enzym SAH-Hydrolase katalysiert die reversible Hydrolyse von SAH zu Adenosin und Homocystein. Jede Untereinheit der SAH-Hydrolase enthält fest gebundenes NAD, das als Kofaktor an der Reaktion beteiligt ist. Das Enzym bindet sowohl cAMP als auch Adenosin, für das es zwei Bindungsstellen mit verschiedenen Affinitäten aufweist, die abhängig sind vom Verhältnis des Kofaktors NAD+/NADH. In der vorliegenden Arbeit wurde das Bindungsverhalten von cAMP an die SAH-Hydrolase in Abhängigkeit vom Kofaktor NAD+/NADH mit Hilfe von Bindungsstudien untersucht. Folgende Ergebnisse wurden erzielt: 1. Der an das Enzym gebundene Kofaktor NAD+/NADH beeinflusst die Assoziations- und Dissoziationsgeschwindigkeit von cAMP an die SAH-Hydrolase. Die NAD+-Form erreichte nach 60 min das Gleichgewicht, während die native SAH-Hydrolase und die NADH-Form 120 min bis zur Einstellung des Gleichgewichts benötigten. 2. Eine Sättigung der nativen SAH-Hydrolase konnte bei 3H-cAMP-Konzentrationen bis 500 nM erreicht werden, für die rekonstituierten Enzymformen waren dazu 3H-cAMP-Konzentrationen bis 5 µM notwendig. Die KD-Werte betrugen 40 nM (natives Enzym), 100 nM (NADH-Form) und 364 nM (NAD+-Form). Die Transformation der Daten nach Scatchard weist auf eine einzige cAMP-Bindungsstelle an allen untersuchten Enzymformen hin. 3. Die untersuchten Adenosin-Analoga zeigten in den Hemmungsversuchen die gleiche Affinität an die native SAH-Hydrolase und an die NADH-Form. Bei der NAD+-Form wiesen alle Substanzen deutlich niedrigere Affinitäten auf. 4. Bei der Markierung mittels 8-Azido-3H-cAMP wiesen die native SAH-Hydrolase...

The impact of cAMP signalling on the dynamics of endothelial tubule formation

Kaczmarek, Milosz
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.79%
Signalling mediated by the ubiquitous cellular messenger cyclic adenosine monophosphate (cAMP) plays a central role in numerous cellular processes. Within vascular endothelial cells (VECs), cAMP signalling influences adhesion to extracellular matrix and formation of VE-cadherin cell-junctions, both part of the VECs angiogenic potential. The angiogenic signalling mechanism within VECs is not completely understood. Here we explored how the components of the cAMP signalling cascade, adenylyl cyclase (AC), protein kinase A (PKA), exchange protein activated by cAMP (EPAC), and phosphodiesterase enzymes (PDEs), influence VEC angiogenic potential. Plating human aortic endothelial cells (HAECs; model VECs) on the pro-angiogenic Matrigel in vitro tubule forming assay, we show that treatment of VECs with adenylate cyclase activator forskolin leads to formation of a distinct phenotype. The structures formed are reminiscent of a monolayer and display some features of early tubule formation. This phenotype was not elicited by activating the two effector proteins (PKA and EPAC) individually. Inhibition of EPAC activity hindered VECs’ response to forskolin and resulted in formation of poor structures, occupying significantly less area and showing significantly less branching than controls. Since the selectivity of cAMP-mediated responses is coordinated in part by actions of cAMP at individual VEC cAMP signalling complexes...

MAPPING AND ANTAGONIZING THE INTERACTION BETWEEN PHOSPHODIESTERASE 3B AND EXCHANGE PROTEIN ACTIVATED BY cAMP-1 ELUCIDATES THEIR ROLES IN ENDOTHELIAL CELL ADHESION

PRITCHARD, LISA
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1750754 bytes; application/pdf
EN; EN
Relevância na Pesquisa
36.79%
The ubiquitous second messenger cAMP acts to integrate and translate information encoded by extracellular messenger molecules, including hormones and neurotransmitters. Intracellular cAMP concentrations are regulated through coordinated changes in the activities of adenylyl cyclases (ACs) and cyclic nucleotide phosphodiesterases (PDEs). Freely diffusing cAMP can reach concentrations sufficient to activate cAMP effector proteins, such as protein kinase A (PKA) or the exchange protein activated by cAMP (EPAC), except in defined compartments where PDEs are localized which allows for spatial and temporal control of the cAMP signal. In human aortic vascular endothelial cells (HAECs) and HEK293T cells we recently identified a macromolecular complex consisting of PDE3B and EPAC and showed that this complex coordinated cAMP-induced effects on adhesion of these cells to fibronectin-coated surfaces. Using “pull-down” assays and peptide array-based approaches we have identified the molecular determinants which coordinate the formation of this complex. Our evidence suggests that the extreme N-terminal 13 amino acids of PDE3B represent the portion of PDE3B that interacts with EPAC. In addition, although several EPAC-encoded peptides were shown to bind PDE3B...

Entre refuge et exil : l’expérience de femmes palestiniennes du camp de Bourj El Barajneh

Caron, Roxane
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
Relevância na Pesquisa
36.85%
Le conflit israélo-palestinien dure depuis plus de 60 ans. Non seulement perdure-t-il, il gagne aussi en complexité. Cette thèse s’intéresse à l’expérience d’exil des Palestiniens et plus particulièrement à celle de femmes palestiniennes vivant en camp de réfugiés au Liban. La mémoire palestinienne a longtemps été, dans son ensemble, occultée dans la littérature, et qui plus est l’expérience des femmes; la façon dont leurs récits sont construits nous le démontre bien. La présente étude s’inscrit donc dans la lignée de travaux qui font une place aux « voix silencieuses » que sont souvent celles des femmes réfugiées palestiniennes des camps. Cette thèse s’appuie sur une approche qualitative – récits de vie et observation participante – et fait suite à une recherche qui a été menée entre 2009 et 2011 dans le camp palestinien de Bourj El Barajneh au Liban. Les résultats dégagés confirment que, dans l’exil, une partie de l’expérience de la nakba palestinienne telle que vécue par les femmes s’est perdue. Ceci dit, si la quasi-absence des femmes caractérise l’exode, on voit ces dernières s’affirmer au fil de l’exil qui devient une réalité durable. Au cours des deux premières décennies...

Adventur Camp SA

Adventur Camp S. A.; Udd Ventures S. A.; MABEL GUERRERO A.
Fonte: Corporação de Fomento da Produção Publicador: Corporação de Fomento da Produção
Tipo: proyecto
Publicado em 19/01/2012
Relevância na Pesquisa
46.52%
Adventur Camp S.A. es una empresa de turismo experiencia-aventura que está implementando campamentos de lujo en Chile enfocados a ofrecer experiencias únicas y exclusivas en la diversa geografía chilena con toda la calidad y servicio que un producto de lujo debe brindar. Nuestro producto está enfocado tanto a turismo de lujo-experiencias viajeros que buscan conocer un país o una región y vivir una experiencia única y diferente así como al negocio de eventos corporativos o viajes de negocio que realizan las empresas.Basándonos en el concepto glamping tendencia con un gran auge a nivel mundial que combina las ventajas de una acampada -sentir la naturaleza en estado puro llegar a parajes solitarios- con los detalles de un hotel de lujo hemos implementado nuestro primer campamento en el Desierto de Atacama.; NUESTRO OBJETIVO PRINCIPAL ES CONSOLIDAR NUESTRO PRODUCTO A NIVEL NACIONAL Y DARLO A CONOCER A NIVEL INTERNACIONAL PRINCIPALMENTE EN EL MERCADO NORTEAMERICANO Y BRASILEÑO. POTENCIAR LAS VENTAS PARA RECOGER LOS FRUTOS DE LA LABOR DE POSICIONAMIENTO DE PRODUCTO QUE SE HA REALIZADO. MEJORAS EN EL PRODUCTO Y AUMENTAR LA CAPACIDAD DE CLIENTES PARA NO PERDER DEMANDA. CRECER EN EL TERRITORIO NACIONAL CON CAMPAMENTO EN OTRAS REGIONES Y A MEDIO PLAZO APUNTAR A PERÚ Y BOLIVIA.; Corporación de Fomento de la Producción

La vulnerabilitat de les zones d'interfase urbana i forestal davant els incendis : estudi de cas de l'incendi de Mont-Roig del Camp (Baix Camp)

Mira i Pou, Núria; Badia i Perpinyà, Anna
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2008 CAT
Relevância na Pesquisa
36.8%
L'incendi de Mont-roig del Camp (Baix Camp) del juliol del 2007 va posar en evidència la manca de planificació i prevenció de les zones que se situen a la interfase entre l'urbà i el forestal. L'experiència dels darrers incendis en zones urbanes ha mostrat la vulnerabilitat d'aquestes àrees davant una nova tipologia d'incendis que no presenta les mateixes característiques que els incendis forestals que tots coneixem, i que s'han anomenat incendis d'interfase urbana i forestal. El present article identifica les variables que incideixen en la vulnerabilitat, per tal d'assenyalar els elements sobre els quals caldria incidir per assolir assentaments menys vulnerables i, per tant, més resistents a la propagació del foc. Aquesta aproximació a la vulnerabilitat de les zones d'interfase de Catalunya davant dels incendis es farà mitjançant una anàlisi teòrica i pràctica a partir de l'incendi de Mont-roig del Camp.; El incendio de Mont-roig del Camp (Baix Camp) de Julio del 2007 puso en evidencia la falta de planificación y prevención de las zonas que se sitúan en la interfase entre lo urbano y lo forestal. La experiencia de los últimos incendios en zonas urbanas ha mostrado la vulnerabilidad de estas áreas delante de una nueva tipología de incendios que no presenta las mismas características que los incendios forestales que todos conocemos...

Functional Interactions and Evolution of cAMP-PKA Signaling in Saccharomyces

KAYIKCI, OMUR
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2013
Relevância na Pesquisa
36.86%

In an attempt to gain more insight on functional evolution of cAMP-PKA pathway I have taken a comparative approach and examined functional interactions of cAMP-PKA signaling in well-studied yeast developmental programs and closely related Saccharomyces sensu stricto. species. I have shown that variation in cAMP-PKA signaling contributes significantly to variation in developmental responses in S cerevisiae. Variation in pseudohyphal growth and sporulation, two inversely correlated developmental strategies to nutrient limitation in yeast, proportional to variation in intracellular cAMP levels. S. cerevisiae strains proficient in pseudohyphal growth have higher intracellular cAMP concentrations relative to strains that sporulate efficiently. Phenotypic, genetic and signaling data presented here suggest that the cAMP-PKA signaling underlies a phenotypic trade-off between sporulation and pseudohyphal growth in S. cerevisiae.

Further investigation into the role of cAMP-PKA signaling in closely related S paradoxus and S bayanus revealed an antagonistic function of cAMP-PKA signaling for developmental responses in S. bayanus. Unlike in S. cerevisiae...

Effect of db-camp on embryonic development of bovine oocytes fertilized with sex sorted semen.

Hernández-Fonseca,Hugo; Nava-Trujillo,Héctor; Sirisathien,Saksiri; Johnson,Lawrence A; Guthrie,David; Welch,Glenn R; Hernández,Adirmo; Brackett,Benjamin G
Fonte: UNIVERSIDAD DEL ZULIA Publicador: UNIVERSIDAD DEL ZULIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2007 EN
Relevância na Pesquisa
36.75%
The objective of this study was to improve sexed bovine embryo production with sorted sperm in chemically defined conditions by supplementing the IVF medium with db-cAMP. Cumulus-oocyte complexes (COCs) were matured for 18 h in supplemented TCM-199 and fertilized with X- or Y-bearing sperm in the presence of heparin (10 µg/ml), db-cAMP (1 µM) or no treatment (control). Presumptive zygotes were cultured 54 h in g-SOF. From 72 to 144 h post- insemination (hpi) embryos were cultured in c-SOF+NEA and from 144 to 192 hpi embryos were placed in maturation medium without hormones. No significant differences were found among treatments for Y-sperm when compared to controls. A significant (P<0.01) improvement in the proportion of cleaved oocytes was found for X-sperm treated with db-cAMP (70.83%) compared to the Y-sperm inseminated oocytes treated wit db-cAMP (46.37%). Treatment with db-cAMP enabled a better (P<0.05) blastocyst formation rate (19.29%) compared to control (8.47%) and heparin (10.44%). Treatment of db-cAMP significantly increased the rate of blastocysts in X-sperm inseminated oocytes (30.77%) compared to Y-sperm inseminated oocytes treated the same (9.68%) and compared to X- and Y-sperm treated with heparin (5.88% and 15.15%...