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41.
Pallavicini M Moroni B Bolchi C Clementi F Fumagalli L Gotti C Vailati S Valoti E Villa L 《Bioorganic & medicinal chemistry letters》2004,14(23):5827-5830
Homochiral E and Z isomers of N-methylprolinal O-isopropyloxime and (1-methyl-2-pyrrolidinyl)methoxyimines were synthesized as candidate bioisosteres of nicotine and its isoxazolic analogue ABT 418. Two of them, namely (S)-2-isopropylideneaminooxymethyl- and (Z)-(S)-2-ethylideneaminooxymethyl-1-methylpyrrolidine, proved to bind at alpha4beta2 nicotinic acetylcholine receptor with submicromolar affinity and remarkable selectivity over alpha7 and muscarinic receptors thus supporting the hypothesized bioisosteric relationship between their methyloxyimino group and the aromatic heterocycles of the reference ligands. 相似文献
42.
Bietti A Boschian G Crisci GM Danese E De Francesco AM Dini M Fontana F Giampietri A Grifoni R Guerreschi A Liagre J Negrino F Radi G Tozzi C Tykot R 《Collegium antropologicum》2004,28(1):41-54
An opportunistic and local choice of raw materials is typically attested in the Lower and Middle Paleolithic industries throughout Italy. The quality of the raw material usually affected the flaking technology and quality of the products. In the Upper Paleolithic and the Mesolithic, raw material procurement strategies were more complex. Flint was exploited both locally, in areas where abundant outcrops of raw materials were available (such as the Lessini mountains), and in distant localities, after which it was transported or exchanged over medium/long distances. Different routes of exchange were thus followed in the various periods; good reconstruction of these routes have been provided by a study of the Garfagnana sites in Northern Tuscany, and the Mesolithic deposit of Mondeval de Sora (Dolomites). An interesting example of a Late Upper Paleolithic flint quarry and workshop were found in Abruzzo, in the San Bartolomeo shelter. The extended trade of obsidian from Lipari, Palmarola and Sardinia to the Italian Peninsula is attested in the Neolithic, with some differences concerning the age and different areas. 相似文献
43.
Anna Olivieri Francesca Gandini Alessandro Achilli Alessandro Fichera Ermanno Rizzi Silvia Bonfiglio Vincenza Battaglia Stefania Brandini Anna De Gaetano Ahmed El-Beltagi Hovirag Lancioni Saif Agha Ornella Semino Luca Ferretti Antonio Torroni 《PloS one》2015,10(10)
Background
Genetic studies support the scenario that Bos taurus domestication occurred in the Near East during the Neolithic transition about 10 thousand years (ky) ago, with the likely exception of a minor secondary event in Italy. However, despite the proven effectiveness of whole mitochondrial genome data in providing valuable information concerning the origin of taurine cattle, until now no population surveys have been carried out at the level of mitogenomes in local breeds from the Near East or surrounding areas. Egypt is in close geographic and cultural proximity to the Near East, in particular the Nile Delta region, and was one of the first neighboring areas to adopt the Neolithic package. Thus, a survey of mitogenome variation of autochthonous taurine breeds from the Nile Delta region might provide new insights on the early spread of cattle rearing outside the Near East.Methodology
Using Illumina high-throughput sequencing we characterized the mitogenomes from two cattle breeds, Menofi (N = 17) and Domiaty (N = 14), from the Nile Delta region. Phylogenetic and Bayesian analyses were subsequently performed.Conclusions
Phylogenetic analyses of the 31 mitogenomes confirmed the prevalence of haplogroup T1, similar to most African cattle breeds, but showed also high frequencies for haplogroups T2, T3 and Q1, and an extremely high haplotype diversity, while Bayesian skyline plots pointed to a main episode of population growth ~12.5 ky ago. Comparisons of Nile Delta mitogenomes with those from other geographic areas revealed that (i) most Egyptian mtDNAs are probably direct local derivatives from the founder domestic herds which first arrived from the Near East and the extent of gene flow from and towards the Nile Delta region was limited after the initial founding event(s); (ii) haplogroup Q1 was among these founders, thus proving that it underwent domestication in the Near East together with the founders of the T clades. 相似文献44.
Bolchi C Pallavicini M Bernini SK Chiodini G Corsini A Ferri N Fumagalli L Straniero V Valoti E 《Bioorganic & medicinal chemistry letters》2011,21(18):5408-5412
Mimetics of the C-terminal CAAX tetrapeptide of Ras protein were designed replacing internal dipeptide AA with 4-amino-2-phenylbenzoic acid and cysteine (C) with 2-amino-4-thiazolyl-, 2-mercapto-4-thiazolyl-, 2-mercapto-4-imidazolyl- and 2-methylmercapto-4-thiazolyl-acetic or propionic acid. The compound in which C is replaced by 2-amino-4-thiazolylacetic acid inhibited FTase activity in the low nanomolar range and showed antiproliferative effect on rat aortic smooth muscle cells interfering with Ras farnesylation. On the basis of these results, 2-aminothiazole can be considered as an alternative to heterocycles, such as pyridine and imidazole, normally used in FTase inhibitors designed as non-thiol CAAX mimetics. 相似文献
45.
Brieda M De Mattia L Dametto E Del Bianco F Nicolosi G 《Indian pacing and electrophysiology journal》2011,11(6):176-179
Upgrading of a pacing system in the presence of a subclavian occlusion is technically challenging. We describe the case of a patient who underwent a successful upgrading procedure of an implantable cardioverter-defibrillator (ICD) to a biventricular defibrillator (ICD-CRT) in the presence of a suboccluded left subclavian vein, using a collateral vein that drained into the contralateral subclavian vein. 相似文献
46.
Aims
In serpentinitic areas non-endemic plants suffer from the serpentine syndrome, due to high Ni and Mg concentrations, low nutrients and Ca/Mg ratio. We evaluated the environment-soil-vegetation relationships in a xeric inner-alpine area (NW Italy), where the inhibited pedogenesis should enhance parent material influences on vegetation.Methods
Site conditions, topsoil properties, plant associations and species on and off serpentinite were statistically associated (51 sites).Results
Serpentine soils had higher Mg and Ni concentrations, but did not differ from non-serpentine ones in nutrient contents. The 15 vegetation clusters often showed substrate specificity. Two components of the Canonical Analysis of Principal Coordinates, respectively related to Mg and to Ni and heat load, identified serpentine vegetation. Random Forests showed that several species were positively correlated with Ni and/or Ca/Mg or Mg, some were negatively associated with high Ni, Mg excess affected only few species. Considering only serpentine sites, nutrients and microclimate were most important.Conclusions
Ni excess most often precludes the presence of plant species on serpentinite, while an exclusion due to Mg is rarer. Endemic species are mostly adapted to both factors. Nutrient scarcity was not specific of serpentine soils in the considered environment. Considering only serpentine sites, nutrient and microclimatic gradients drove vegetation variability. 相似文献47.
Reid JF Sokolova V Zoni E Lampis A Pizzamiglio S Bertan C Zanutto S Perrone F Camerini T Gallino G Verderio P Leo E Pilotti S Gariboldi M Pierotti MA 《Molecular cancer research : MCR》2012,10(4):504-515
Altered expression of miRNAs is associated with development and progression of various human cancers by regulating the translation of oncogenes and tumor suppressor genes. In colorectal cancer, these regulators complement the Vogelstein multistep model of pathogenesis and have the potential of becoming a novel class of tumor biomarkers and therapeutic targets. Using quantitative real-time PCR, we measured the expression of 621 mature miRNAs in 40 colorectal cancers and their paired normal tissues and identified 23 significantly deregulated miRNAs. We subsequently evaluated their association with clinical characteristics of the samples and presence of alterations in the molecular markers of colorectal cancer progression. Expression levels of miR-31 were correlated with CA19-9 and miR-18a, miR-21, and miR-31 were associated with mutations in APC gene. To investigate the downstream regulation of the differentially expressed miRNAs identified, we integrated putative mRNA target predictions with the results of a meta-analysis of seven public gene expression datasets of normal and tumor samples of colorectal cancer patients. Many of the colorectal cancer deregulated miRNAs computationally mapped to targets involved in pathways related to progression. Here one promising candidate pair (miR-1 and MET) was studied and functionally validated. We show that miR-1 can have a tumor suppressor function in colorectal cancer by directly downregulating MET oncogene both at RNA and protein level and that reexpression of miR-1 leads to MET-driven reduction of cell proliferation and motility, identifying the miR-1 downmodulation as one of the events that could enhance colorectal cancer progression. 相似文献
48.
Niemann HH Petoukhov MV Härtlein M Moulin M Gherardi E Timmins P Heinz DW Svergun DI 《Journal of molecular biology》2008,377(2):489-500
The Listeria monocytogenes surface protein InlB binds to the extracellular domain of the human receptor tyrosine kinase Met, the product of the c-met proto-oncogene. InlB binding activates the Met receptor, leading to uptake of Listeria into normally nonphagocytic host cells. The N-terminal half of InlB (InlB321) is sufficient for Met binding and activation. The complex between this Met-binding domain of InlB and various constructs of the Met ectodomain was characterized by size exclusion chromatography and dynamic light scattering, and structural models were built using small-angle X-ray scattering and small-angle neutron scattering. Although most receptor tyrosine kinase ligands induce receptor dimerization, InlB321 consistently binds the Met ectodomain with a 1:1 stoichiometry. A construct comprising the Sema and PSI domains of Met, although sufficient to bind the physiological Met ligand hepatocyte growth factor/scatter factor, does not form a complex with InlB321 in solution, highlighting the importance of Met Ig domains for InlB binding. Small-angle X-ray scattering and small-angle neutron scattering measurements of ligand and receptor, both free and in complex, reveal an elongated shape for the receptor. The four Ig domains form a bent, rather than a fully extended, conformation, and InlB321 binds to Sema and the first Ig domain of Met, in agreement with the recent crystal structure of a smaller Met fragment in complex with InlB321. These results call into question whether receptor dimerization is the basic underlying event in InlB321-mediated Met activation and demonstrate differences in the mechanisms by which the physiological ligand hepatocyte growth factor/scatter factor and InlB321 bind and activate the Met receptor. 相似文献
49.
Pfaff AW Mousli M Sénégas A Marcellin L Takikawa O Klein JP Candolfi E 《International journal for parasitology》2008,38(2):249-258
IFN-gamma production is a hallmark of acute infection with the protozoan parasite Toxoplasma gondii. The tryptophan-catabolising enzyme indoleamine 2,3-dioxygenase (IDO), as well as inducible nitric oxide synthase (NOS2) are induced by IFN-gamma and can play extremely diverse roles in immune regulation, defence against pathogens and physiological homeostasis. We investigated the regulation of these two central enzymes in the placenta during acute infection of pregnant female mice. Using IFN-gamma receptor knockout (IFNgammaR-/-) mice, we showed that IDO is not constitutively expressed in term placentas. In contrast, NOS2 expression was observed, largely dependent on IFN-gamma signalling. Upon infection with the avirulent PRU strain of T. gondii, IDO mRNA expression was induced in an IFNgammaR-dependent manner. Surprisingly, NOS2 mRNA was severely suppressed. Importantly, we showed in crossing experiments of heterozygote (IFNgammaR+/-) mothers with IFNgammaR-/- males and vice versa that IDO expression largely depends on the presence of IFN-gamma receptors on foetal cells, and to a lesser extent on maternal cells. Immunohistochemical analysis localised foetal IDO production to invasive trophoblasts within the maternal part of the placenta. The placental vascular endothelium only stained positive when the mothers possessed functional IFN-gamma receptors. In contrast, placental NOS2 expression, but also its suppression following infection, seems to be largely dependent on IFN-gamma signalling in maternal cells. Neither factor appears to regulate placental T. gondii growth, as we observed no difference in parasite numbers between (+/-) and (-/-) foetuses. Taken together, our results demonstrate the crucial role of the foetus in placental IDO, but not NOS2, production following T. gondii infection. 相似文献
50.
Hartings H Berardo N Mazzinelli GF Valoti P Verderio A Motto M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,117(6):831-842
In the present study we have analyzed the genetic diversity pattern in a sample of 54 Italian maize landraces, using morphological
traits and molecular markers. Although the 54 landraces surveyed in this study were restricted to Lombardy, the core region
of maize production in Italy, our data revealed a large genetic heterogeneity for both morphological and molecular traits
in the accessions analyzed. Additionally, our data confirm that the AFLP markers produced a high frequency of polymorphic
bands and were able to unequivocally fingerprint each of the landraces considered. Cluster analysis based on AFLP markers
displayed a clearer separation of the accessions in comparison to morphological data. Different populations were divided into
four major clusters reflecting the geographical origin and seasonal employment of the landraces analyzed. Molecular analysis
of variance showed significant (P < 0.01) differences among groups, among populations within groups, and among individuals within populations. Approximately
74% of the total variance could be attributed to differences within populations. Conversely, a lower level of differentiation
was detected among groups (~4%). Regarding population structures, the genetic distance between populations (F
ST = 0.25 ± 0.3) and the degree of inbreeding within groups (F
SC = 0.22 ± 0.2), did not diverge significantly, while both significantly differed from the degree of relatedness between markers
within groups (F
CT = 0.04 ± 0.03). Results are discussed in relation to a suitable conservation method. 相似文献