Search results for "CID"
showing 10 items of 19479 documents
Phytochemical investigation of the needles of Abies nebrodensis (Lojac.) Mattei
2019
Abies nebrodensis (Lojac.) Mattei (Pinaceae) is a species living in a very small population only in a confined area of Sicily. In this study, the dichloromethane extract of the leaves was analyzed. Apart from three already known metabolites namely dehydroabietic acid; maltol; and rheosmin, previously detected in other species of Abies, a lanostane derivative was isolated. Its chemical structure was elucidated by means of extensive spectroscopic methods.
Cytotoxic necrotizing factor type 2 produced by virulent Escherichia coli modifies the small GTP-binding proteins Rho involved in assembly of actin s…
1994
Cytotoxic necrotizing factor type 2 (CNF2) produced by Escherichia coli strains isolated from intestinal and extraintestinal infections is a dermonecrotic toxin of 110 kDa. We cloned the CNF2 gene from a large plasmid carried by an Escherichia coli strain isolated from a lamb with septicemia. Hydropathy analysis of the deduced amino acid sequence revealed a largely hydrophilic protein with two potential hydrophobic transmembrane domains. The N-terminal half of CNF2 showed striking homology (27% identity and 80% conserved residues) to the N-terminal portion of Pasteurella multocida toxin. Methylamine protection experiments and immunofluorescence studies suggested that CNF2 enters the cytosol…
Targeting the mevalonate pathway for improved anticancer therapy.
2009
The mevalonate pathway is important for the generation of isoprene moieties thereby providing the basis for the biosynthesis of molecules required for maintaining membrane integrity, steroid production and cell respiration. Additionally, isoprene precursors are indispensable for the prenylation of regulatory proteins such as Ras and Ras-homologous (Rho) GTPases. These low molecular GTP-binding proteins play key roles in numerous signal transduction pathways stimulated upon activation of cell surface receptors by ligand binding. Thus, Ras/Rho proteins eventually regulate cell proliferation, tumor progression and cell death induced by anticancer therapeutics. Lipid modification of Ras/Rho pro…
Inhibition of small G proteins of the Rho family by statins orClostridium difficiletoxin B enhances cytokine-mediated induction of NO synthase II
2000
In order to investigate the involvement of Ras and/or Rho proteins in the induction of the inducible isoform of nitric oxide synthase (NOS II) we used HMG-CoA reductase inhibitors (statins) and Clostridium difficile toxin B (TcdB) as pharmacological tools. Statins indirectly inhibit small G proteins by preventing their essential farnesylation (Ras) and/or geranylgeranylation (Rho). In contrast, TcdB is a glucosyltransferase and inactivates Rho-proteins directly. Human A549/8- and DLD-1 cells as well as murine 3T3 fibroblasts were preincubated for 18 h with statins (1–100 μM) or TcdB (0.01–10 ng ml−1). Then NOS II expression was induced by cytokines. NOS II mRNA was measured after 4–8 h by R…
Activation of astroglial phospholipase D activity by phorbol ester involves ARF and Rho proteins.
2000
Primary cultures of rat cortical astrocytes express phospholipase D (PLD) isoforms 1 and 2 as determined by RT-PCR and Western blot. Basal PLD activity was strongly (10-fold) increased by 4beta-phorbol-12beta,13alpha-dibutyrate (PDB) (EC(50): 56 nM), an effect which was inhibited by Ro 31-8220 (0.1-1 microM), an inhibitor of protein kinase C (PKC), and by brefeldin A (10-100 microg/ml), an inhibitor of ADP-ribosylating factor (ARF) activation. Pretreatment of the cultures with Clostridium difficile toxin B-10463 (0.1-1 ng/ml), which inactivates small G proteins of the Rho family, led to a breakdown of the astroglial cytoskeleton; concomitantly, PLD activation by PDB was reduced by up to 50%…
Metabotropic glutamate receptors activate phospholipase D in astrocytes through a protein kinase C-dependent and Rho-independent pathway.
2003
Metabotropic glutamate receptors (mGluRs) are G protein-coupled receptors that mediate phospholipase D (PLD) activation in brain, but the mechanism underlying this response remains unclear. Here we used primary cultures of astrocytes as a cell model to explore the mechanism that links mGluRs to PLD. Glutamate activated both phospholipase C (PLC) and PLD with equal potency and this effect was mimicked by L-cysteinesulfinic acid, a putative neurotransmitter previously shown to activate mGluRs coupled to PLD, but not PLC, in adult brain. PLD activation by glutamate was dependent on Ca(2+) mobilization and fully blocked by both protein kinase C (PKC) inhibitors and PKC down-regulation, suggesti…
Inhibition of Rho modulates cytokine-induced prostaglandin E2 formation in renal mesangial cells.
2003
Stimulation of rat mesangial cells for 24 h with interleukin-1β(IL-1β) plus forskolin (Fk) leads to a marked increase in prostaglandin E 2 (PGE 2 ) synthesis. This effect is further enhanced by the small G-protein Rho inhibitor toxin A. A similar increase in PGE 2 formation is obtained with Y27632, a Rho-dependent kinase inhibitor, and with lovastatin, a hydroxymethylglutaryl-coenzyme A inhibitor which depletes cells from geranylgeranyl moieties and thus blocks Rho activation. In parallel to the increased PGE 2 synthesis, a potentiation of IL-1β-induced secretory group IIA phospholipases A 2 (sPLA 2 -IIA) protein expression also occurs by Rho inhibition. However, only toxin A triggers an in…
Trattamento infiltrativo ecoguidato d'anca versus infiltrazioni associate a terapia riabilitativa: studio randomizzato controllato
2013
La coxartrosi è una malattia, caratterizzata da deterioramento della cartilagine e delle strutture articolari, che si manifesta clinicamente con dolore ingravescente e conseguente riduzione della funzionalità. Presso l'U.O.C. di Riabilitazione dell'A.O.U.P. Paolo Giaccone, tra febbraio 2008 e gennaio 2013 sono stati reclutati 224 soggetti sottoposti ad un ciclo infiltrativo che prevedeva 3 somministrazioni intrarticolari di acido ialuronico, eseguite sotto guida ecografica, a distanza di 45 giorni l'una dall'altra; i pazienti sono stati suddivisi, in modo random, in 2 gruppi (gruppo A e gruppo B). Il gruppo A è stato sottoposto solamente a trattamento infiltrativo; al gruppo B è stato assoc…
Séisme 2016 et Amatrice: au-delà des représentations sensationnalistes, la recherche-action militante
2021
Dopo il terremoto del 2016-2017, l'Appennino centrale italiano sta attraversando una lunga fase di transizione tra l'urbicidio e la ricostruzione. La riflessione emerge da una ricerca sui processi di ri-territorializzazione della città di Amatrice, nel cuore del cratere del terremoto: un lavoro all'incrocio tra la geografia sociale e culturale, sostenuto da nove mesi di lavoro sul campo. Dopo aver descritto il sistema di gestione dell'emergenza, ci si interroga sulla dimensione di rappresentazione del disastro. Criticando l'iconografia sensazionalista, si descrive l'esperienza di ricerca di Emidio di Treviri, un collettivo di ricerca-azione nato per documentare e analizzare i processi socio…
La prise en compte de la stratégie agricole améliore la compréhension de l’effet des pratiques sur les communautés adventices
2019
National audience; Les agriculteurs présents dans une même situation de production peuvent différer dans leurs objectifs et donc leurs pratiques. Afin de tester l’effet d’une pratique particulière (ex. désherbage chimique) sur la communauté adventice, il est donc nécessaire de tenir compte de l’ensemble des autres pratiques, formant une stratégie agricole. Nous avons ainsi développé 14 indicateurs décrivant les pratiques agricoles enquêtées sur la zone de Fénay de 2004 à 2016 auprès des 23 agriculteurs de la zone. L’originalité des indicateurs est qu’ils situent chaque parcelle par rapport aux autres parcelles ayant mis en oeuvre la même culture la même année sur la zone. Ceci nous a permis…