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141.
Brandi L Lazzarini A Cavaletti L Abbondi M Corti E Ciciliato I Gastaldo L Marazzi A Feroggio M Fabbretti A Maio A Colombo L Donadio S Marinelli F Losi D Gualerzi CO Selva E 《Biochemistry》2006,45(11):3692-3702
In the course of a microbial product screening aimed at the discovery of novel antibiotics acting on bacterial protein synthesis, a complex of three structurally related tetrapeptides, namely, GE81112 factors A, B, and B1, was isolated from a Streptomyces sp. The screening was based on a cell-free assay of bacterial protein synthesis driven by a model mRNA containing natural initiation signals. In this study we report the production, isolation, and structure determination of these novel, potent and selective inhibitors of cell-free bacterial protein synthesis, which stably bind the 30S ribosomal subunit and inhibit the formation of fMet-puromycin. They did not inhibit translation by yeast ribosomes in vitro. Spectroscopic analyses revealed that they are tetrapeptides constituted by uncommon amino acids. While GE81112 factors A, B, and B1 were effective in inhibiting bacterial protein synthesis in vitro, they were less active against Gram-positive and Gram-negative bacterial cells. Cells grown in minimal medium were more susceptible to the compounds than those grown in rich medium, and this is most likely due to competition or regulation by medium components during peptide uptake. The novelty of the chemical structure and of the specific mode of action on the initiation phase of bacterial protein synthesis makes GE81112 a unique scaffold for designing new drugs. 相似文献
142.
Cerioni L Palomba L Brüne B Cantoni O 《Biochemical and biophysical research communications》2006,339(1):126-131
Our previous work has shown that non-toxic concentrations of peroxynitrite nevertheless commit U937 cells to mitochondrial permeability-transition (MPT)-dependent necrosis that is however prevented by a parallel survival signaling pathway involving cytosolic phospholipase A2 (cPLA2)-dependent arachidonic acid release and PKCalpha activation associated with the cytosolic translocation of Bad. The present study provides evidence of an early mitochondrial translocation of PKCalpha. Inhibition of the survival signaling at the level of either cPLA2, or PKC, was invariably associated with prevention of the mitochondrial localization of PKCalpha, with the mitochondrial translocation of Bad and Bax and with a very rapid lethal response. Collectively, the results presented in this study demonstrate that peroxynitrite, while committing U937 cells to necrosis, triggers a parallel signaling response leading to the cytosolic localization of two important members of the Bcl-2 family implicated in the onset of MPT. 相似文献
143.
Estrogen receptor alpha interacts with Galpha13 to drive actin remodeling and endothelial cell migration via the RhoA/Rho kinase/moesin pathway 总被引:5,自引:0,他引:5
144.
Emiliano Manzo M. Letizia Ciavatta Salem Bakkas Guido Villani Mario Varcamonti Anna Zanfardino Margherita Gavagnin 《Phytochemistry letters》2009,2(4):211-215
Analysis of the secondary metabolites content of the brown alga Dictyota ciliolata, collected from Oualidia lagoon (Morocco), revealed the presence of xenicane and guaiane homologous diterpenes. Two new xenicanes, 1 and 2, co-occurring with the known dictyodial, dictyol C and dictyol H, have been isolated and characterized by spectral methods, mainly by NMR techniques. Compound 2 displayed mild antifungal activity against Candida albicans. 相似文献
145.
Trine Well?v Boesgaard Anette Prior Gjesing Niels Grarup Jarno Rutanen Per-Anders Jansson Marta Letizia Hribal Giorgio Sesti Andreas Fritsche Norbert Stefan Harald Staiger Hans H?ring Ulf Smith Markku Laakso Oluf Pedersen Torben Hansen for the EUGENE Consortium 《PloS one》2009,4(9)
Backround
A meta-analysis combining results from three genome-wide association studies and followed by large-scale replication identified six novel type 2 diabetes loci. Subsequent studies of the effect of these variants on estimates of the beta-cell function and insulin sensitivity have been inconclusive. We examined these variants located in or near the JAZF1 (rs864745), THADA (rs7578597), TSPAN8 (rs7961581), ADAMTS9 (rs4607103), NOTCH2 (rs10923931) and the CDC123/CAMK1D (rs12779790) genes for associations with measures of pancreatic beta-cell function and insulin sensitivity.Methodology/Results
Oral and intravenous glucose stimulated insulin release (n = 849) and insulin sensitivity (n = 596) estimated from a hyperinsulinemic euglycemic clamp were measured in non-diabetic offspring of type 2 diabetic patients from five European populations. Assuming an additive genetic model the diabetes-associated major C-allele of rs4607103 near ADAMTS9 associated with reduced insulin-stimulated glucose uptake (p = 0.002) during a hyperinsulinemic euglycemic clamp. However, following intravenous and oral administration of glucose serum insulin release was increased in individuals with the C-allele (p = 0.003 and p = 0.01, respectively). A meta-analyse combining clamp and IVGTT data from a total of 905 non-diabetic individuals showed that the C-risk allele associated with decreased insulin sensitivity (p = 0.003) and increased insulin release (p = 0.002). The major T-allele of the intronic JAZF1 rs864745 conferring increased diabetes risk was associated with increased 2nd phase serum insulin release during an IVGTT (p = 0.03), and an increased fasting serum insulin level (p = 0.001). The remaining variants did not show any associations with insulin response, insulin sensitivity or any other measured quantitative traits.Conclusion
The present studies suggest that the diabetogenic impact of the C-allele of rs4607103 near ADAMTS9 may in part be mediated through decreased insulin sensitivity of peripheral tissues. 相似文献146.
Maccallini C Patruno A Lannutti F Ammazzalorso A De Filippis B Fantacuzzi M Franceschelli S Giampietro L Masella S Felaco M Re N Amoroso R 《Bioorganic & medicinal chemistry letters》2010,20(22):6495-6499
A series of N-substituted acetamidines and 2-methylimidazole derivatives structurally related to W1400 were synthesized and evaluated as Nitric Oxide Synthase (NOS) inhibitors. Analogs with sterically hindering isopropyl and phenyl substituents on the benzylic carbon connecting the aromatic core of W1400 to the acetamidine nitrogen, showed good inhibitory potency for nNOS (IC(50)=0.2 and 0.3 μM) and selectivity over eNOS (500 and 1166) and to a lesser extent over iNOS (50 and 100). A molecular modeling study allowed to shed light on the effects of the structural modifications on the selectivity of the designed inhibitors toward the different NOS isoforms. 相似文献
147.
Stefania Ferro Laura De Luca Maria Letizia Barreca Sara De Grazia Frauke Christ Zeger Debyser Alba Chimirri 《Bioorganic & medicinal chemistry》2010,18(15):5510-5518
The life cycle of HIV-1 requires extensive assistance from the integrase (IN) enzyme which therefore constitutes an attractive therapeutic target for the development of anti-AIDS agents. We herein report the synthesis and biological evaluation of new HIV integrase strand-transfer inhibitors (INSTIs) which proved to be also potent anti-HIV agents. The binding mode of the most representative molecules were also studied by induced-fit docking (IFD). The obtained IFD results were consistent with the mechanism of action proposed for this class of IN inhibitors, that is metal chelating/binding agents. 相似文献
148.
149.
Tarantino U Capone A Planta M D'Arienzo M Letizia Mauro G Impagliazzo A Formica A Pallotta F Patella V Spinarelli A Pazzaglia U Zarattini G Roselli M Montanari G Sessa G Privitera M Verdoia C Corradini C Feola M Padolino A Saturnino L Scialdoni A Rao C Iolascon G Brandi ML Piscitelli P 《Arthritis research & therapy》2010,12(6):R226-9
Introduction
We aimed to assess the incidence and hospitalization rate of hip and "minor" fragility fractures in the Italian population.Methods
We carried out a 3-year survey at 10 major Italian emergency departments to evaluate the hospitalization rate of hip, forearm, humeral, ankle, and vertebral fragility fractures in people 45 years or older between 2004 and 2006, both men and women. These data were compared with those recorded in the national hospitalizations database (SDO) to assess the overall incidence of fragility fractures occurring at hip and other sites, including also those events not resulting in hospital admissions.Results
We observed 29,017 fractures across 3 years, with hospitalization rates of 93.0% for hip fractures, 36.3% for humeral fractures, 31.3% for ankle fractures, 22.6% for forearm/wrist fractures, and 27.6% for clinical vertebral fractures. According to the analyses performed with the Italian hospitalization database in year 2006, we estimated an annual incidence of 87,000 hip, 48,000 humeral, 36,000 ankle, 85,000 wrist, and 155,000 vertebral fragility fractures in people aged 45 years or older (thus resulting in almost 410,000 new fractures per year). Clinical vertebral fractures were recorded in 47,000 events per year.Conclusions
The burden of fragility fractures in the Italian population is very high and calls for effective preventive strategies. 相似文献150.
Maria Letizia Giardino Torchia Elena Ciaglia Anna Maria Masci Laura Vitiello Manuela Fogli Andrea la Sala Domenico Mavilio Luigi Racioppi 《PloS one》2010,5(6)