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991.
Antonella Miola Sonia Favaretto Ismaele Sostizzo Gianna Valentini Alessandra Asioli 《Vegetation History and Archaeobotany》2010,19(5-6):513-529
In this work we investigate the development of a salt marsh environment during the Holocene marine transgression in the North Adriatic coast (North Italy) near the pre-Roman and Roman towns of Cittanova and Concordia Sagittaria. Pollen, plant macrofossils, non-pollen palynomorphs (NPPs) and foraminifers are analysed in cores and archaeological excavations to indicate the development of salt marsh plant communities. Other independent proxies (foraminifers, plant macrofossils, molluscs) confirm the ecological interpretation based on pollen records. The relevance of NPPs as indicators of salt marsh environment is evaluated. Linings of foraminifers are the most frequent NPP type, recorded in 85% of the brackish sediments. They may tentatively be referred to the genus Ammonia, a very common benthonic genus in the present lagoons of the North Adriatic Sea. Radiocarbon dates available from previous work allow the salt marsh development to be dated in the sector from the east of the Lagoon of Venice to the Lagoon of Caorle. Near Cittanova, salt marshes developed before 6700 yrs cal. b.p. At Concordia Sagittaria, the first evidence dates from ca. 6700 yrs cal. b.p. and a phase of freshwater conditions is recorded in the sediments of ca. 4500 yrs cal. b.p. 相似文献
992.
Ferdinando Fiorino Beatrice Severino Francesca De Angelis Elisa Perissutti Elisa Magli Francesco Frecentese Antonella Esposito Paola Massarelli Cristina Nencini Vincenzo Santagada Giuseppe Caliendo 《Bioorganic & medicinal chemistry letters》2010,20(9):2978-2982
N′-Cyanoisonicotinamidine derivatives, linked to an arylpiperazine moiety, were prepared to identify highly selective and potent 5-HT1A ligands as potential pharmacological tools in studies of wide spread psychiatric disorders. The combination of structural elements (heterocyclic nucleus, alkyl chain and 4-substituted piperazine) known to be critical in order to have affinity on 5-HT1A receptor and the proper selection of substituents led to compounds with high specificity and affinity towards serotoninergic receptors. In binding studies, several molecules showed affinity in nanomolar and subnanomolar range at 5-HT1A and moderate to no affinity for other relevant receptors (5-HT2A, 5-HT2C, D1, D2, α1 and α2). N′-Cyano-N-(3-(4-(pyridin-2-yl)piperazin-1-yl)propyl)isonicotinamidine (4o) with Ki = 0.038 nM, was the most active and selective derivative for the 5-HT1A receptor with respect to other serotoninergic, dopaminergic and adrenergic receptors. 相似文献
993.
Giovanna Delogu Gianni Podda Marcella Corda Maria Benedetta Fadda Antonella Fais Benedetta Era 《Bioorganic & medicinal chemistry letters》2010,20(20):6138-6140
A series of novel bis-salicylaldehydes were synthesised and evaluated as tyrosinase inhibitors using a tyrosinase-dependent l-DOPA oxidation assay. The bis-salicylaldehydes exhibited greater inhibitory activity than salicylaldehyde. Our data suggests that these novel compounds may serve as a structural template for the design and development of novel tyrosinase inhibitors. 相似文献
994.
Alice Pavlowsky Antonella Gianfelice Marta Pallotto Alice Zanchi Hugo Vara Malik Khelfaoui Pamela Valnegri Xavier Rezai Silvia Bassani Dario Brambilla Jiri Kumpost Jaroslav Blahos Michel J. Roux Yann Humeau Jamel Chelly Maria Passafaro Maurizio Giustetto Pierre Billuart Carlo Sala 《Current biology : CB》2010,20(2):103-115
995.
Marco L. Lolli Barbara Rolando Paolo Tosco Shilpi Chaurasia Antonella Di Stilo Loretta Lazzarato Eva Gorassini Riccardo Ferracini Simonetta Oliaro-Bosso Roberta Fruttero Alberto Gasco 《Bioorganic & medicinal chemistry》2010,18(7):2428-2438
A new series of bisphosphonates bearing either the nitrogen-containing NO-donor furoxan (1,2,5-oxadiazole 2-oxide) system or the related furazan (1,2,5-oxadiazole) in lateral chain has been developed. pKa values and affinity for hydroxyapatite were determined for all the compounds. The products were able to inhibit osteoclastogenesis on RAW 246.7 cells at 10 μM concentration. The most active compounds were further assayed on human PBMC cells and on rat microsomes. Unlike most nitrogen-containing bisphosphonates which target farnesyl pyrophosphate synthase, experimental and theoretical investigations suggest that the activity of our derivatives may be related to different mechanisms. The furoxan derivatives were also tested for their ability to relax rat aorta strips in view of their potential NO-dependent vasodilator properties. 相似文献
996.
Irene Matera Antonella Gullotto Silvia Tilli Marta Ferraroni Andrea Scozzafava Fabrizio Briganti 《Inorganica chimica acta》2008,361(14-15):4129-4137
A multicopper oxidase, the fungal laccase glycoenzyme from the white-rot basidiomycete fungus Trametes (Funalia) trogii, was crystallized and its crystal structure was solved at 1.58 Å using molecular replacement techniques.Model refinement resulted in R-factor and R-free values of 17.4% and 19.0%, respectively. The T. trogii laccase structural model reveals the presence of a ligand bound to the T1 active site which resembles a p-toluate molecule, such bound compound is most probably a fungal metabolite. The p-toluate is bound into the T1 active site of the laccase forming, with one of the carboxylate oxygens, a H-bond with His455, one of the T1 copper ion ligands, whereas the methyl group presents hydrophobic interactions within a pocket composed by Phe331, Phe336, Pro390 and Val162.The coordination geometries, the bond distances and the oxidation states of the T1 and T2/T3 copper active sites are analyzed and discussed in terms of the enzymatic mechanism and catalytic functionality. 相似文献
997.
998.
999.
Paola Spessotto Antonella Zucchetto Massimo Degan Bruna Wasserman Carla Danussi Riccardo Bomben Roberto Perris Vincenzo Canzonieri Oriano Radillo Alfonso Colombatti Valter Gattei 《Matrix biology》2007,26(6):473-484
Cell adhesion and motility are central aspects in the pathophysiology of B cell chronic lymphocytic leukemia (B-CLL), but the role of specific extracellular matrix proteins is still to be completely unveiled. Purified peripheral blood neoplastic cells of B-CLL patients migrated poorly on laminins-111,-411,-511, but showed pronounced motility on laminin (LM)-332 in a high percentage of cases. B-CLL cell motility on LM-332 was mediated by the alpha3beta1 integrin and was preferentially observed in cells carrying a mutated IgV(H) gene profile. Within normal lymph nodes, LM-332 was circumscribed around blood vessels and to areas corresponding to marginal zones, where it was deposited in a pattern reminiscent of reticular fibers. Conversely, in B-CLL involved lymph nodes, a positive LM-332 reticular mesh was diffusely evident, throughout the disrupted nodal architecture. In the present study we identified LM-332 as a crucial motility-promoting factor for B-CLL lymphocytes and as a potential constituent favoring the dissemination of B-CLL lymphocytes through vascular basement membranes and possibly lymph node compartments. 相似文献
1000.
Antonella Preti Ken MacKenzie Kate A. Spivey Leslie R. Noble Catherine S. Jones Ralph G. Appy Graham J. Pierce 《Journal of fish biology》2020,97(2):354-361
This study documented the parasite faunas of the spiral valves of blue sharks Prionace glauca (L. 1758) and common thresher sharks Alopias vulpinus (Bonnaterre, 1788) caught in the California Current Large Marine Ecosystem (CCLME) north of the Mexican border. The spiral valves of 18 blue and 19 thresher sharks caught in the CCLME from 2009 to 2013 were examined for parasites. Seven parasite taxa were found in blue sharks and nine in threshers. The tetraphyllidean cestode Anthobothrium sp. (78% prevalence) was the most common parasite in blue sharks, and the phyllobothriid cestode Paraorygmatobothrium sp. (90% prevalence) was the most common in threshers. An adult nematode of the genus Piscicapillaria was found in threshers for the first time and may be a new species. Adult individuals of Hysterothylacium sp. were found in both shark species. The adult acanthocephalan Rhadinorhynchus cololabis and remains of the parasitic copepod Pennella sp. – both parasites of Pacific saury, Cololabis saira – were found in the intestines of threshers, indicating recent feeding on saury. This study paves the way for a more comprehensive examination, including more samples and a wider variety of shark species, to provide a greater understanding of shark feeding behaviour and possibly provide information on shark population biology. 相似文献