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101.
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103.
Dr. Ermanno Danese 《Facies》1999,41(1):41-54
Summary The development of carbonate ramp depositional systems in the Neogene of the Mediterranean Region represents a widespread
feature so far analysed in several papers. It is striking to note that the evolution of upper Miocene carbonate ramps, characterized
by the presence of coralgal bioherms, highlights the events leading to the Messinian salinity crisis. The coralgal bioherms
of preevaporite Messinian age exhibit fossil assemblages indicating marine waters with normal salinity, whereas stromatolitic
and microbial encrustations underline the deterioration of the environment during the Messinian salinity crisis. Maiella Mountain
is a broad carbonate massif located in Abruzzo (Central Italy). The late lower Oligocene-Messinian part of its stratigraphic
succession consists of stacked non-tropical carbonate ramp deposits related to third and higher order sequences. The investigations
performed in the southernmost portion of the massif allowed to recognize a complete fourth order carbonate depositional sequence
on a homoclinal ramp of pre-evaporite Messinian age. The presence of small coralgal patch reefs and overlaying microbial encrustations
is significant. A transect exhibits the stratigraphic framework of the area. The data show how local parameters play a notable
role in the development of these deposits. 相似文献
104.
Niemann HH Jäger V Butler PJ van den Heuvel J Schmidt S Ferraris D Gherardi E Heinz DW 《Cell》2007,130(2):235-246
The tyrosine kinase Met, the product of the c-met proto-oncogene and the receptor for hepatocyte growth factor/scatter factor (HGF/SF), mediates signals critical for cell survival and migration. The human pathogen Listeria monocytogenes exploits Met signaling for invasion of host cells via its surface protein InlB. We present the crystal structure of the complex between a large fragment of the human Met ectodomain and the Met-binding domain of InlB. The concave face of the InlB leucine-rich repeat region interacts tightly with the first immunoglobulin-like domain of the Met stalk, a domain which does not bind HGF/SF. A second contact between InlB and the Met Sema domain locks the otherwise flexible receptor in a rigid, signaling competent conformation. Full Met activation requires the additional C-terminal domains of InlB which induce heparin-mediated receptor clustering and potent signaling. Thus, although it elicits a similar cellular response, InlB is not a structural mimic of HGF/SF. 相似文献
105.
D'Annibale A Leonardi V Federici E Baldi F Zecchini F Petruccioli M 《Applied microbiology and biotechnology》2007,74(5):1135-1144
Contaminated soil from a historical industrial site and containing sulfide ore ashes and aromatic hydrocarbons underwent sequential
leaching by 0.5 M citrate and microbial treatments. Heavy metals leaching was with the following efficiency scale: Cu (58.7%)
> Pb (55.1%) > Zn (44.5%) > Cd (42.9%) > Cr (26.4%) > Ni (17.7%) > Co (14.0%) > As (12.4%) > Fe (5.3%) > Hg (1.1%) and was
accompanied by concomitant removal of organic contaminants (about 13%). Leached metals were concentrated into an iron gel,
produced during ferric citrate fermentation by the metal-resistant strain BAS-10 of Klebsiella oxytoca. Concomitantly, the acidic leached soil was bioaugmented with Allescheriella sp. DABAC 1, Stachybotrys sp. DABAC 3, Phlebia sp. DABAC 9, Pleurotus pulmonarius CBS 664.97, and Botryosphaeria rhodina DABAC P82. B. rhodina was most effective, leading to a significant depletion of the most abundant contaminants, including 7-H-benz[DE]anthracene-7-one,
9,10-anthracene dione and dichloroaniline isomers, and to a marked detoxification as assessed by the mortality test with the
Collembola Folsomia candida Willem. The overall degradation activities of B. rhodina and P. pulmonarius appeared to be significantly enhanced by the preliminary metal removal. 相似文献
106.
Bolchi C Pallavicini M Rusconi C Diomede L Ferri N Corsini A Fumagalli L Pedretti A Vistoli G Valoti E 《Bioorganic & medicinal chemistry letters》2007,17(22):6192-6196
2-o-Tolyl or 2-o-anisyl substituted 4-hydroxy- and 4-carboxybenzamides of methionine, etherified and amidified with 2-hydroxymethyl- and 2-aminomethylpyridodioxane, respectively, are described as inhibitors of Ras protein farnesyltransferase (FTase). Of the sixteen compounds, resulting from the substitution pattern of benzamide and the configuration of the two stereocenters, seven inhibited FTase activity with potencies in the nanomolar range. They were all 2-oxymethylpyridodioxane ethers and, among them, the four o-tolyl substituted stereoisomers also showed micromolar antiproliferative effect on human aortic smooth muscle cells interfering with Ras farnesylation. The docking analysis enlightened significant differences in enzyme interaction between oxymethylpyridodioxane and aminomethylpyridodioxane derivatives. 相似文献
107.
Communication through gap junctions was first suggested to have a role in the social control of cell growth over 30 years ago. However, despite extensive experimentation, the importance of gap junctions as a general mechanism of growth control remains to be established. A number of different studies have shown that a common early response of cells in culture to polypeptide growth factors such as PDGF is a rapid and transient inhibition of cell communication suggesting that a cell may have to lose communication with its neighbors before it can undergo cell division. Here we show that 3T3 A31 fibroblasts exposed to PDGF exhibit a 50% decrease in cell communication as measured by dye transfer in the absence of significant changes in the cellular content and distribution of Cx43. Likewise, PDGF inhibited cell communication in cells transfected either with a vector which did not contain a cDNA or with an expression vector encoding full-length Cx43 fused to a c-myc tag (Cx43-M). In contrast, 3T3 A31 fibroblasts transfected with an expression construct encoding a deletion mutant of Cx43 (Cx43-256M) consisting of amino acids 1-256 of Cx43 fused to a c-myc tag maintain high levels of gap junction activity following exposure to PDGF. These results suggest that sites which trigger loss of cell communication in response to PDGF are located within amino acids 257 to 382 of the Cx43 molecule. Cells transfected with an expression vector encoding full-length Cx43 fused to a c-myc tail exhibited a reduced basal growth rate compared to both parent cells and cells transfected with a control vector but maintained a strong mitogenic response to PDGF. In contrast, both the basal growth rate and the mitogenic response to PDGF was markedly reduced in cells which expressed Cx43-256M consistent with the hypothesis that loss of cell communication is required before a cell can respond to mitogenic stimuli. 相似文献
108.
Cristiano Bolchi Ermanno Valoti Matteo Binda Francesca Fasoli Rossana Ferrara Laura Fumagalli Cecilia Gotti Rosanna Matucci Giulio Vistoli Marco Pallavicini 《Bioorganic & medicinal chemistry letters》2013,23(23):6481-6485
A series of acetylcholine carbamoyl analogues, cyclised at the carbamate moiety or at the cationic head or at both, were tested for binding affinity at muscarinic and neuronal nicotinic receptors (nAChRs). While no muscarinic affinity was found, submicromolar Ki values, similar to that of carbachol, were measured at α4β2 nAChRs for the enantiomers of 5-dimethylaminomethyl- and 5-trimethylammoniomethyl-2-oxazolidinone, 2 and 2a, and for (S)-N-methylprolinol carbamate (S)-3. Methylation of oxazolidinone nitrogen of 2 and 2a and of N-methylprolinol nitrogen of (S)-3 and, even more, hybridization of cyclic carbamate substructure (oxazolidinone) with cyclic cationic head (N-methylpyrrolidine) markedly lower the nicotinic affinity. Docking results were consistent with SAR analysis highlighting the interaction capabilities of (R)-2a and (S)-3 and the negative effect of intracyclic nitrogen methylation and of double cyclisation. 相似文献
109.
110.
Cristina Olivieri Luca Ermini Ermanno Rizzi Giorgio Corti Raoul Bonnal Stefania Luciani Isolina Marota Gianluca De Bellis Franco Rollo 《PloS one》2010,5(1)