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31.
M. Eugenia Giorgi Laura Ratier Rosalía Agusti Alberto C. C. Frasch Rosa M. de Lederkremer 《Glycoconjugate journal》2010,27(5):549-559
Trypanosoma cruzi, the agent of Chagas disease, expresses a unique enzyme, the trans-sialidase (TcTS) involved in the transfer of sialic acid
from host glycoconjugates to mucins of the parasite. The enzyme is shed to the medium and may affect the immune system of
the host. We have previously described that lactose derivatives effectively inhibited the transfer of sialic acid to N-acetyllactosamine. Lactitol also prevented the apoptosis caused by the TcTS, although it is rapidly eliminated from the circulatory
system. In this paper we report covalent conjugation of polyethylene glycol (PEG) with lactose, lactobionolactone and benzyl
β-D-galactopyranosyl-(1→6)-2-amino-2-deoxy-α-D-glucopyranoside (1) with the hope to improve the bioavailability, though retaining their inhibitory properties. Different conjugation methods
have been used and the behavior of the PEGylated products in the TcTS reaction was studied. 相似文献
32.
Cappelli A Valenti S Mancini A Giuliani G Anzini M Altieri S Bortolussi S Ferrari C Clerici AM Zonta C Carraro F Filippi I Giorgi G Donati A Ristori S Vomero S Concas A Biggio G 《Bioconjugate chemistry》2010,21(12):2213-2221
Potential boron neutron capture therapy (BNCT) agents have been designed on the basis of the evidence about translocator protein (TSPO) overexpression on the outer mitochondrial membrane of tumor cells. The structure of the first TSPO ligand bearing a carborane cage (compound 2d) has been modified in order to find a suitable candidate for in vivo studies. The designed compounds were synthesized and evaluated for their potential interaction with TSPO and tumor cells. In vitro biological evaluation showed in the case of fluoromethyl derivative 4b a nanomolar TSPO affinity very similar to that of 2d, a significantly lower cytotoxicity, and a slightly superior performance as boron carrier toward breast cancer cells. Moreover, compound 4b could be used as a 1?F magnetic resonance imaging (MRI) agent as well as labeled with 11C or 1?F to obtain positron emission tomography (PET) radiotracers in order to apply the "see and treat" strategy in BNCT. 相似文献
33.
Magdalena Lebiedzinska Agnieszka Karkucinska-Wieckowska Carlotta Giorgi Elzbieta Karczmarewicz Ewa Pronicka Paolo Pinton Jerzy Duszynski Maciej Pronicki Mariusz R. Wieckowski 《BBA》2010,1797(6-7):952-960
p66Shc, the growth factor adaptor protein, can have a substantial impact on mitochondrial metabolism through regulation of cellular response to oxidative stress. We investigated relationships between the extent of p66Shc phosphorylation at Ser36, mitochondrial dysfunctions and an antioxidant defense reactions in fibroblasts derived from five patients with various mitochondrial disorders (two with mitochondrial DNA mutations and three with methylglutaconic aciduria and genetic defects localized, most probably, in nuclear genes). We found that in all these fibroblasts, the extent of p66Shc phosphorylation at Ser36 was significantly increased. This correlated with a substantially decreased level of mitochondrial superoxide dismutase (SOD2) in these cells. This suggest that SOD2 is under control of the Ser36 phosphorylation status of p66Shc protein. As a consequence, an intracellular oxidative stress and accumulation of damages caused by oxygen free radicals are observed in the cells. 相似文献
34.
Proper neuronal function and several forms of synaptic plasticity are highly dependent on precise control of mRNA translation, particularly in dendrites. We find that eIF4AIII, a core exon junction complex (EJC) component loaded onto mRNAs by pre-mRNA splicing, is associated with neuronal mRNA granules and dendritic mRNAs. eIF4AIII knockdown markedly increases both synaptic strength and GLUR1 AMPA receptor abundance at synapses. eIF4AIII depletion also increases ARC, a protein required for maintenance of long-term potentiation; arc mRNA, one of the most abundant in dendrites, is a natural target for nonsense-mediated decay (NMD). Numerous new NMD candidates, some with potential to affect synaptic activity, were also identified computationally. Two models are presented for how translation-dependent decay pathways such as NMD might advantageously function as critical brakes for protein synthesis in cells such as neurons that are highly dependent on spatially and temporally restricted protein expression. 相似文献
35.
Kaizer J Ganszky I Speier G Rockenbauer A Korecz L Giorgi M Réglier M Antonczak S 《Journal of inorganic biochemistry》2007,101(6):893-899
The cerium(IV)-mediated oxidation of 3-hydroxy-4'-methylflavone (1) proceeds by H-atom abstraction forming the flavonoxy radical (7), and the subsequent combination of its resonance forms leads to the 3-hydroxy-4'-methylflavone dehydro dimer (9). The above system serves as direct evidence for the intermediacy of the flavonoxy radical, its spin delocalization, and also indirect evidence for valence tautomerism as a key step on the substrate activation both in the quercetinase and its biomimic model system. 相似文献
36.
Zavan B Giorgi C Bagnara GP Vindigni V Abatangelo G Cortivo R 《European journal of histochemistry : EJH》2007,51(Z1):1-8
Hyaluronan-based scaffold were used for in vitro commitment of human and rat bone marrow mesenchymal stem cells (MSC). Cells were cultured either in monolayer and in 3D conditions up to 35 days. In order to monitor the differentiating processes molecular biology and morphological studies were performed at different time points. All the reported data supported the evidence that both human and rat MSC grown onto hyaluronan-derived three-dimensional scaffold were able to acquire a unique phenotype of chondrocytes and osteocytes depending on the presence of specific differentiation inducing factors added into the culture medium without significative differences in term of time expression of extracellular matrix proteins. 相似文献
37.
Christine A. Bricault James M. Kovacs Joseph P. Nkolola Karina Yusim Elena E. Giorgi Jennifer L. Shields James Perry Christy L. Lavine Ann Cheung Katharine Ellingson-Strouss Cecelia Rademeyer Glenda E. Gray Carolyn Williamson Leonidas Stamatatos Michael S. Seaman Bette T. Korber Bing Chen Dan H. Barouch 《Journal of virology》2015,89(5):2507-2519
38.
Ecological index of maturity to evaluate the vegetation disturbance of areas affected by restoration work: a practical example of its application in an area of the Southern Alps
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This paper presents the ecological index of maturity (EIM), a new index for evaluating the vegetation disturbance of an area affected by environmental restoration measures based on the study of plant communities. The EIM is the result of the unification and development of some floristic‐vegetational indices devised by Taffetani and Rismondo (2009) and Rismondo et al. (2011) to assess the ecological functionality of agro‐ecosystems. The EIM provides a value between 0 (high vegetation disturbance) and 9 (undisturbed vegetation), obtained by considering three distinct variables of the species of a plant community: phytosociological class, chorotype, and coverage. Starting from the measure of the degree of maturity of the vegetation (dynamic stage of succession), EIM values tend to decrease the greater the coverage of exotic species and the lower the coverage of endemic species present in the plant community. A practical example, in which the EIM is applied to a mountainous area in the Southern Alps (Northern Italy) that, following a landslide, was subject to soil bioengineering work aimed at slope stabilization and environmental restoration, is provided in order to understand the importance and features of the EIM. 相似文献
39.
Benedetti S Rinalducci S Benvenuti F Francogli S Pagliarani S Giorgi L Micheloni M D'Amici GM Zolla L Canestrari F 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,833(1):12-18
Aphanizomenon flos-aquae (AFA) is a blue-green alga and represents a nutrient-dense food source. In this study the presence of phycocyanin (PC), a blue protein belonging to the photosynthetic apparatus, has been demonstrated in AFA. An efficient method for its separation has been set up: PC can be purified by a simple single step chromatographic run using a hydroxyapatite column (ratio A620/A280 of 4.78), allowing its usage for health-enhancing properties while eliminating other aspecific algal components. Proteomic investigation and HPLC analysis of purified AFA phycobilisomes revealed that, contrary to the well-characterized Synechocystis and Spirulina spp., only one type of biliprotein is present in phycobilisomes: phycocyanins with no allo-phycocyanins. Two subunit polypeptides of PC were also separated: the beta subunit containing two bilins as chromophore and the alpha subunit containing only one. 相似文献
40.
William A Cafruny Richard G Duman Grace HW Wong Suleman Said Pam Ward-Demo Raymond RR Rowland Eric A Nelson 《Virology journal》2006,3(1):1-17