Search results for "Cg"
showing 10 items of 999 documents
Differential roles of cAMP and cGMP in megakaryocyte maturation and platelet biogenesis
2012
The cyclic nucleotides cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) regulate the activity of protein kinase A (PKA) and protein kinase G (PKG), respectively. This process helps maintain circulating platelets in a resting state. Here we studied the role of cAMP and cGMP in the regulation of megakaryocyte (MK) differentiation and platelet formation. Cultured, platelet-producing MKs were differentiated from fetal livers harvested from 13.5 days postcoital mouse embryos. MK development was accompanied by a dramatic increase in cAMP production and expression of soluble guanylate cyclase, PKG, and PKA as well as their downstream targets vasodilator-stimulated ph…
Potential and limitations of PKA/ PKG inhibitors for platelet studies
2021
Cyclic nucleotides (cAMP and cGMP) and corresponding protein kinases, protein kinase A (PKA) and protein kinase G (PKG), are the main intracellular mediators of endothelium-derived platelet inhibitors. Pharmacological PKA/PKG inhibitors are often used to discriminate between these two kinase activities and to analyze their underlying mechanisms. Previously we showed that all widely used PKG inhibitors (KT5823, DT3, RP isomers) either did not inhibit PKG or inhibited and even activated platelets independently from PKG. In this study, we examined several PKA inhibitors as well as inhibitors of adenylate and guanylate cyclases to reveal their effects on platelets and establish whether they are…
Activation of cGMP-dependent Protein Kinase Iβ Inhibits Interleukin 2 Release and Proliferation of T Cell Receptor-stimulated Human Peripheral T Cells
2000
Several major functions of type I cGMP-dependent protein kinase (cGK I) have been established in smooth muscle cells, platelets, endothelial cells, and cardiac myocytes. Here we demonstrate that cGK Ibeta is endogenously expressed in freshly purified human peripheral blood T lymphocytes and inhibits their proliferation and interleukin 2 release. Incubation of human T cells with the NO donor, sodium nitroprusside, or the membrane-permeant cGMP analogs PET-cGMP and 8-pCPT-cGMP, activated cGK I and produced (i) a distinct pattern of phosphorylation of vasodilator-stimulated phosphoprotein, (ii) stimulation of the mitogen-activated protein kinases ERK1/2 and p38 kinase, and, upon anti-CD3 stimu…
Phosphorylation of CalDAG-GEFI by protein kinase A prevents Rap1b activation.
2013
Summary Background Signaling via protein kinase A (PKA) and protein kinase G (PKG) is critical for maintaining platelets in the resting state. Both kinases down-regulate the activity of the small GTPase Rap1b, a critical signaling switch for integrin activation and platelet aggregation. However, the mechanism of Rap1b regulation by PKA and PKG is largely unknown. Objective To identify the PKA phosphorylation sites in calcium and diacylglycerol-regulated guanine nucleotide exchange factor I (CalDAG-GEFI), the main GEF for Rap1b in platelets, and the effect of CalDAG-GEFI phosphorylation in Rap1b activation. Methods The phosphorylation sites in CalDAG-GEFI were identified by radio-active phos…
Manger (et boire) dans les usines occupées du printemps 1936
2016
International audience; Avec celles de 1968, les grèves du Front populaire constituent l’un des épisodes les plus marquants et les plus étudiés de l’histoire du mouvement ouvrier français, élevé au rang de « mythes sociaux » . Si la chronologie des évènements est aujourd’hui bien connue, nos connaissances sur l’organisation pratique et technique de ces grèves demeurent néanmoins limitées. Et quand il s’agit d’aborder la question du ravitaillement, nous entrons cette fois dans une sorte de « no man’s land » de la recherche. Aussi s’intéresser à la nourriture dans les usines occupées de 1936 présente un double intérêt, scientifique d’abord au vu de l’état de l’art, et historique ensuite quand…
Mutual Information Analysis of Brain-Body Interactions during different Levels of Mental stress
2019
In this work, we analyze brain-heart interactions during different mental states computing mutual information (MI) between the dynamic activity of different physiological systems. In 18 healthy subjects monitored in a relaxed resting state and during a mental arithmetic and a serious game task, multichannel EEG, one lead ECG, respiration and blood volume pulse were collected via wireless non-invasive biosensors. From these signals, synchronous 300-second time series were extracted measuring brain activity via the δ, θ, α, and β EEG power, and activity of the body district via the ECG R-R interval η, the respiratory amplitude ϱ and the pulse arrival time π. MI was computed using a linear est…
Roughness and vegetation parameterizations at L-band for soil moisture retrievals over a vineyard field
2015
Abstract The capability of L-band radiometry to monitor surface soil moisture (SM) at global scale has been analyzed in numerous studies, mostly in the framework of the ESA SMOS and NASA SMAP missions. To retrieve SM from L-band radiometric observations, two significant effects have to be accounted for, namely soil roughness and vegetation optical depth. In this study, soil roughness effects on retrieved SM values were evaluated using brightness temperatures acquired by the L-band ELBARA-II radiometer, over a vineyard field at the Valencia Anchor Station (VAS) site during the year 2013. Different combinations of the values of the model parameters used to account for soil roughness effects (…
Evaluating equilibrium and non-equilibrium transport of bromide and isoproturon in disturbed and undisturbed soil columns.
2007
19 pages; International audience; In this study, displacement experiments of isoproturon were conducted in disturbed and undisturbed columns of a silty clay loam soil under similar rainfall intensities. Solute transport occurred under saturated conditions in the undisturbed soil and under unsaturated conditions in the sieved soil because of a greater bulk density of the compacted undisturbed soil compared to the sieved soil. The objective of this work was to determine transport characteristics of isoproturon relative to bromide tracer. Triplicate column experiments were performed with sieved (structure partially destroyed to simulate conventional tillage) and undisturbed (structure preserve…
MEDLEM database, a data collection on large Elasmobranchs in the Mediterranean and Black seas
2020
The Mediterranean Large Elasmobranchs Monitoring (MEDLEM) database contains more than 3,000 records (with more than 4,000 individuals) of large elasmobranch species from 21 different countries around the Mediterranean and Black seas, observed from 1666 to 2017. The principal species included in the archive are the devil ray (1,868 individuals), the basking shark (935 individuals), the blue shark (622 individuals), and the great white shark (342 individuals). In the last decades, other species such as the thresher shark (187 individuals), the shortfin mako (180 individuals), and the spiny butterfly ray (138) were reported with increasing frequency. This was possibly due to increased public a…
Sociālo prasmju pilnveide piecgadīgiem bērniem ar autismu pirmsskolā
2022
Kvalifikācijas darba tēma ir “Sociālo prasmju pilnveide piecgadīgiem bērniem ar autismu pirmsskolā”. Darba mērķis ir noskaidrot paņēmienus, ar kuru palīdzību var pilnveidot sociālās prasmes 5 gadus veciem bērniem ar autismu pirmsskolā. Darbā izmantoti literatūras un elektroniskie informācijas avoti. Tika analizēts 5 gadus vecu bērnu attīstības raksturojums, sociālo prasmju pilnveides nepieciešamība, metodes sociālo prasmju pilnveidei pirmsskolā bērniem ar autismu, teorētiķu ieteikumi sociālo prasmju pilnveidē bērniem ar autismu. Darba teorētiskajā daļā ir veikta literatūras, 5 gadus vecu bērnu attīstības raksturojums, raksturota sociālo prasmju pilnveides nepieciešamība bērniem ar autismu, …