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791.
Anna Maria Mercuri Carla Alberta Accorsi Marta Bandini Mazzanti Giovanna Bosi Andrea Cardarelli Donato Labate Marco Marchesini Giuliana Trevisan Grandi 《Vegetation History and Archaeobotany》2006,16(1):43-60
The paper presents a synthesis of the on-site archaeobotanical investigations of the Terramara di Montale, one of the most important sites of the Terramara cultural system which characterised the Po Plain in the Middle-Late Bronze Age (1650–1200 b.c.). Samples for pollen analysis and macroremains, including seed/fruit and wood/charcoal records, were collected from stratigraphic sequences and occupation levels during the excavations 1996–2001. The results permitted the reconstruction of the main characteristics of the landscape which at the onset of the Terramara rapidly passed from a natural, more forested landscape with mixed oak wood and conifers to a more open and anthropic landscape characterised by cereal fields, pastures and meadows. People felled oaks and other trees such as Populus/Salix and Fraxinus to make piles or walls for houses. Wood from these species was also recorded as charcoal in the hearths. Palynological and carpological data show that the inhabitants of the Terramara largely founded their economy on cereals (mainly Triticum aestivum/durum, T. dicoccum and Hordeum vulgare). They also grew a few legumes (Vicia faba var. minor, Vicia sp. and Lens culinaris). There was also grazing by domestic animals, mainly ovicaprines but also pigs and cattle, and these were fed exploiting wild plants such as Carpinus. In the paper the four main steps of the history of the Terramara are described (before the Terramara, the onset, the Terramara phase, the decline) during which both human influence and climatic changes were important. At the onset of the Terramara (around 1600 b.c.) a warm and possibly dry phase occurred. The intense use of the territory and a climatic deterioration at around 1300 b.c. might have triggered the decline of the Terramara di Montale. 相似文献
792.
Cesare Ravazzi Marta Donegana Elisa Vescovi Enrico Arpenti Marco Caccianiga Petra Kaltenrieder Laurent Londeix Stefano Marabini Stefano Mariani Roberta Pini Gian Battista Vai Lucia Wick 《Vegetation History and Archaeobotany》2006,15(4):357-371
We describe a new palaeobotanical site at Bubano quarry on the easternmost Po plain, northern Italy. Pollen and macrofossils from river and marsh sediments demonstrate the occurrence of Picea in a Pinus sylvestris forest growing in a radius of some tens of kilometres south of the sedimentation place, at the beginning of the Late-glacial interstadial. The Late-glacial and Holocene history of Picea in the northern Apennines is reconstructed on the basis of the palaeobotanical record. The sharp climatic continentality increase eastwards across the northern Apennines from the Tyrrhenian to the Adriatic coast is considered significant for the survival of Picea during the Late-glacial. The most critical phase of survival is related to the moisture changes and consequent Abies competition associated with the last glacial-interglacial transition and the early Holocene. The residual spruce populations expanded during the middle Holocene. The history of Picea in the northern Apennines is a case of ineffective interglacial spread of tree populations from pre-existing stands of LGM (Last Glacial Maximum) and Late-glacial age. 相似文献
793.
Kim KS Lu S Cornelius LA Lombardo LJ Borzilleri RM Schroeder GM Sheng C Rovnyak G Crews D Schmidt RJ Williams DK Bhide RS Traeger SC McDonnell PA Mueller L Sheriff S Newitt JA Pudzianowski AT Yang Z Wild R Lee FY Batorsky R Ryder JS Ortega-Nanos M Shen H Gottardis M Roussell DL 《Bioorganic & medicinal chemistry letters》2006,16(15):3937-3942
Synthesis and SAR of substituted pyrrolotriazine-4-one analogues as Eg5 inhibitors are described. Many of these analogues displayed potent inhibitory activities in the Eg5 ATPase and A2780 cell proliferation assays. In addition, pyrrolotriazine-4-one analogue 26 demonstrated in vivo efficacy in an iv P388 murine leukemia model. Both NMR and X-ray crystallographic studies revealed that these analogues bind to an allosteric site on the Eg5 protein. 相似文献
794.
De Filippis V Frasson R Fontana A 《Protein science : a publication of the Protein Society》2006,15(5):976-986
3-Nitrotyrosine (NT) is approximately 10(3)-fold more acidic than Tyr, and its absorption properties are strongly pH-dependent. NT absorbs radiation in the wavelength range where Tyr and Trp emit fluorescence (300-450 nm), and it is essentially nonfluorescent. Therefore, NT may function as an energy acceptor in resonance energy transfer (FRET) studies for investigating ligand protein interactions. Here, the potentialities of NT were tested on the hirudin thrombin system, a well-characterized protease inhibitor pair of key pharmacological importance. We synthesized two analogs of the N-terminal domain (residues 1-47) of hirudin: Y3NT, in which Tyr3 was replaced by NT, and S2R/Y3NT, containing the substitutions Ser2 --> Arg and Tyr3 --> NT. The binding of these analogs to thrombin was investigated at pH 8 by FRET and UV/Vis-absorption spectroscopy. Upon hirudin binding, the fluorescence of thrombin was reduced by approximately 50%, due to the energy transfer occurring between the Trp residues of the enzyme (i.e., the donors) and the single NT of the inhibitor (i.e., the acceptor). The changes in the absorption spectra of the enzyme inhibitor complex indicate that the phenate moiety of NT in the free state becomes protonated to phenol in the thrombin-bound form. Our results indicate that the incorporation of NT can be effectively used to detect protein protein interactions with sensitivity in the low nanomolar range, to uncover subtle structural features at the ligand protein interface, and to obtain reliable Kd values for structure activity relationship studies. Furthermore, advances in chemical and genetic methods, useful for incorporating noncoded amino acids into proteins, highlight the broad applicability of NT in biotechnology and pharmacological screening. 相似文献
795.
The "mu loop," an 11-residue loop spanning amino acid residues 33-43, is a characteristic structural feature of the mu class of glutathione transferases. To assess the contribution of the mu loop to the structure and function of rat GST M1-1, amino acid residues 35-44 (35GDAPDYDRSQ44) were excised by deletion mutagenesis, resulting in the "Deletion Enzyme." Kinetic studies reveal that the Km values of the Deletion Enzyme are markedly increased compared with those of the wild-type enzyme: 32-fold for 1-chloro-2,4-dinitrobenzene, 99-fold for glutathione, and 880-fold for monobromobimane, while the Vmax value for each substrate is increased only modestly. Results from experiments probing the structure of the Deletion Enzyme, in comparison with that of the wild-type enzyme, suggest that the secondary and quaternary structures have not been appreciably perturbed. Thermostability studies indicate that the Deletion Enzyme is as stable as the wild-type enzyme at 4 degrees C and 10 degrees C, but it rapidly loses activity at 25 degrees C, unlike the wild-type enzyme. In the temperature range of 4 degrees C through 25 degrees C, the loss of activity of the Deletion Enzyme is not the result of a change in its structure, as determined by circular dichroism spectroscopy and sedimentation equilibrium centrifugation. Collectively, these results indicate that the mu loop is not essential for GST M1-1 to maintain its structure nor is it required for the enzyme to retain some catalytic activity. However, it is an important determinant of the enzyme's affinity for its substrates. 相似文献
796.
Biotreatability of polycyclic aromatic hydrocarbons in brackish sediments: Preliminary studies of an integrated monitoring 总被引:1,自引:0,他引:1
Federica Abbondanzi Luigi Bruzzi Tiziana Campisi Annalisa Frezzati Roberta Guerra Antonella Iacondini 《International biodeterioration & biodegradation》2006,57(4):214-221
An integrated monitoring, of chemical, microbiological and ecotoxicological parameters, was performed for a biotreatability study of polycyclic aromatic hydrocarbons (PAHs)—contaminated brackish sediments. Three slurry reactors were prepared, consisting of (a) a slurry with sediment and seawater called TQ slurry, to evaluate the intrinsic bioremediation potential, (b) a slurry with the addition of a selected microbial consotrium called BIO slurry, to evaluate the bioaugmentation effect, (c) a slurry with the addition of Soya lecithin called LEC slurry, to evaluate the effect of the addition of a natural surfactant. Biodegradation results showed that both BIO and LEC slurries enhanced PAHs removal, increasing the biodegradation rate for 5- and 6-ring PAHs. Furthermore, ecotoxicological response (Microtox® assay on whole sediment, aqueous extract and organic extract) demonstrated a detoxification of the PAHs initial mixture only for BIO slurry. The findings that aerobic PAHs degradation can be stimulated via inoculation with adapted sediment bacteria suggest that a bioaugmentation process may be a useful strategy for ex-situ treatment. 相似文献
797.
Joanna Romanowska Agnieszka Szymańska-Michalak Jerzy Boryski Jacek Stawiński Adam Kraszewski Roberta Loddo Giuseppina Sanna Gabriella Collu Barbara Secci Paolo La Colla 《Bioorganic & medicinal chemistry》2009,17(9):3489-3498
Di-aryl nucleoside phosphotriesters have been explored as a new type of pronucleotides for the purpose of anti-HIV-1 therapy and efficient synthetic protocols, based on H-phosphonate chemistry, have been developed for the preparation of this class of compounds. It was found that anti-HIV-1 activity of the phosphotriesters bearing an antiviral nucleoside moiety (AZT, ddA) and also ddU was due, at least partially, to intracellular conversion into the corresponding nucleoside 5′-monophosphates, and their efficiency correlated well with the pKa values of the aryloxy groups present. 相似文献
798.
Michele Tonelli Iana Vazzana Bruno Tasso Vito Boido Fabio Sparatore Maurizio Fermeglia Maria Silvia Paneni Paola Posocco Sabrina Pricl Paolo La Colla Cristina Ibba Barbara Secci Gabriella Collu Roberta Loddo 《Bioorganic & medicinal chemistry》2009,17(13):4425-4440
Twelve aminoarylazocompounds (A–C) and 46 aryltriazene 7 derivatives (D–G) have been synthesized and evaluated in cell-based assays for cytotoxicity and antiviral activity against a panel of 10 RNA and DNA viruses.Eight aminoazocompounds and 27 aryltriazene derivatives exhibited antiviral activity, sometimes of high level, against one or more viruses. A marked activity against BVDV and YFV was prevailing among the former compounds, while the latter type of compounds affected mainly CVB-2 and RSV. None of the active compounds inhibited the multiplication of HIV-1, VSV and VV.Arranged in order of decreasing potency and selectivity versus the host cell lines, the best compounds are the following; BVDV: 1 > 7 > 8 > 4; YFV: 7 > 5; CVB-2: 25 > 56 > 18; RSV: 14 > 20 > 55 > 38 > 18 > 19; HSV-1: 2. For these compounds the EC50 ranged from 1.6 μM (1) to 12 μM (18), and the S. I. from 19.4 (1) to 4.2 (2).Thus the aminoarylazo and aryltriazene substructures appear as interesting molecular component for developing antiviral agents against ss RNA viruses, particularly against RSV and BVDV, which are important human and veterinary pathogens.Finally, molecular modeling investigations indicated that compounds of structure A–C, active against BVDV, could work targeting the viral RNA-dependent RNA-polymerase (RdRp), having been observed a good agreement between the trends of the estimated IC50 and the experimental EC50 values. 相似文献
799.
Maria Virginia Petry Lucas Krüger Vanda Simone da Silva Fonseca Jaqueline Brummelhaus Roberta da Cruz Piuco 《Journal of Ornithology》2009,150(3):601-606
Cory’s Shearwater, Calonectris diomedea, is a pelagic seabird that winters in the waters off the state of Rio Grande do Sul in southern Brazil. Elsewhere, its diet
is comprised mostly of fish and cephalopods, but dietary details out of the breeding season are unknown. The present study
analysed the diet of Cory’s Shearwater along the coast of Rio Grande do Sul based on the stomach contents of 185 birds found
dead during beach surveys between July 1997 and July 1998. Food items were classified taxonomically and non-food items were
categorized. The taxa identified included the cephalopods Argonauta nodosa and Histioteuthis sp. and the fish Paralonchurus brasiliensis, Porichthys porosissimus, and Prionotus punctatus. Cephalopods were present in 97% of stomachs and fish in 33% of stomachs. Synthetic materials were found in 81% of stomachs.
Our data corroborate the general ideas of Procellariiform diet during migration. The high amount of synthetic materials indicates
the pollution of the marine environments of southern Brazil and we call attention to this situation. 相似文献
800.