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11.
Flavio De Maio Giuseppe Maulucci Mariachiara Minerva Saber Anoosheh Ivana Palucci Raffaella Iantomasi Valentina Palmieri Serena Camassa Michela Sali Maurizio Sanguinetti Wilbert Bitter Riccardo Manganelli Marco De Spirito Giovanni Delogu 《PloS one》2014,9(11)
PE_PGRS proteins are unique to the Mycobacterium tuberculosis complex and a number of other pathogenic mycobacteria. PE_PGRS30, which is required for the full virulence of M. tuberculosis (Mtb), has three main domains, i.e. an N-terminal PE domain, repetitive PGRS domain and the unique C-terminal domain. To investigate the role of these domains, we expressed a GFP-tagged PE_PGRS30 protein and a series of its functional deletion mutants in different mycobacterial species (Mtb, Mycobacterium bovis BCG and Mycobacterium smegmatis) and analysed protein localization by confocal microscopy. We show that PE_PGRS30 localizes at the mycobacterial cell poles in Mtb and M. bovis BCG but not in M. smegmatis and that the PGRS domain of the protein strongly contributes to protein cellular localization in Mtb. Immunofluorescence studies further showed that the unique C-terminal domain of PE_PGRS30 is not available on the surface, except when the PGRS domain is missing. Immunoblot demonstrated that the PGRS domain is required to maintain the protein strongly associated with the non-soluble cellular fraction. These results suggest that the repetitive GGA-GGN repeats of the PGRS domain contain specific sequences that contribute to protein cellular localization and that polar localization might be a key step in the PE_PGRS30-dependent virulence mechanism. 相似文献
12.
Francesco Nonnis Marzano Fabio Fiori Guogang Jia Mariachiara Chiantore 《Polar Biology》2000,23(11):753-758
The paucity of investigations on the presence of artificial radionuclides and their bioaccumulation in Antarctic fauna is
due to the erroneous belief that this area is pristine. We report evidence that significant levels of the artificial radionuclides
Sr-90, Cs-137, Am-241 and plutonium isotopes can be found in sponges, bivalves, krill and demersal fish fauna of Terra Nova
Bay (Ross Sea), sometimes with a seasonal pattern. Increasing concentrations of Cs-137 were detected in the bivalve Adamussium colbecki (Antarctic scallop) during austral summer months, as a result of major trophic activity and changes in metabolic rates. Bioconcentration
factors for artificial radionuclides in different Antarctic species are presented and discussed in relation to their different
trophic strategies. Unexpectedly high radiocesium bioconcentration factors determined in bivalves suggested the particular
role played by filter feeding in bioaccumulation, particularly in summer when radionuclide bioavailability is enhanced. The
feeding preference of the trematomiid fish Trematomus bernacchii for the scallop A. colbecki is confirmed, not only by fish gut content analyses, but also through radiometric results. Transuranics bioaccumulation by
sensitive species allowed some interesting comparisons on the different plutonium contamination of the southern hemisphere
with respect to the northern one.
Accepted: 25 April 2000 相似文献
13.
Giorgia Pedini Mariachiara Buccarelli Fabrizio Bianchi Laura Pacini Giulia Cencelli Quintino Giorgio DAlessandris Maurizio Martini Stefano Giannetti Franceschina Sasso Valentina Melocchi Maria Giulia Farace Tilmann Achsel Luigi M. Larocca Lucia Ricci-Vitiani Roberto Pallini Claudia Bagni 《Cell death & disease》2022,13(8)
14.
The drug-metabolizing enzymes of olfactory and respiratory epithelium of cattle were determined. The data of nasal tissues were compared to those of bovine liver. Both oxidative and nonoxidative enzyme activities were investigated. Many compounds including testosterone were used as substrates for the P450-dependent monooxygenase activities. The results demonstrated that the P450 content and all the activities assayed including reduced nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase were much higher in the olfactory than in the respiratory mucosa and for some activities (hexamethyl-phosphoramide and dimethylnitrosamine N-demethylase, aniline hydroxylase, and ethoxycoumarin O-deethylase) the values in the olfactory tissue were even markedly higher than those of liver. Also the activities of some nonoxidative enzymes such as glutathione S-transferase, uridine 5'-diphosphate (UDP)-glucuronyl-transferase, and epoxide hydrolase were higher in the olfactory than in the respiratory mucosa but lower than in liver. The results taken together suggest that the olfactory and respiratory epithelium of cattle, which contain in addition to a wide array of nonoxidative enzymes multiple forms of P450, can be useful and easily available tissues to study the biotransformation processes of odorants. 相似文献
15.
Iolanda D’Alimonte Eleonora Nargi Mariachiara Zuccarini Paola Lanuti Patrizia Di Iorio Patricia Giuliani Lucia Ricci-Vitiani Roberto Pallini Francesco Caciagli Renata Ciccarelli 《Purinergic signalling》2015,11(3):331-346
Glioblastoma multiforme (GBM), the most common and aggressive brain tumor in humans, comprises a population of stem-like cells (GSCs) that are currently investigated as potential target for GBM therapy. Here, we used GSCs isolated from three different GBM surgical specimens to examine the antitumor activity of purines. Cultured GSCs expressed either metabotropic adenosine P1 and ATP P2Y receptors or ionotropic P2X7 receptors. GSC exposure for 48 h to 10–150 μM ATP, P2R ligand, or to ADPβS or MRS2365, P2Y1R agonists, enhanced cell expansion. This effect was counteracted by the PY1R antagonist MRS2500. In contrast, 48-h treatment with higher doses of ATP or UTP, which binds to P2Y2/4R, or 2′(3′)-O-(4-benzoylbenzoyl)-ATP (Bz-ATP), P2X7R agonist, decreased GSC proliferation. Such a reduction was due to apoptotic or necrotic cell death but mostly to growth arrest. Accordingly, cell regrowth and secondary neurosphere formation were observed 2 weeks after the end of treatment. Suramin, nonselective P2R antagonist, MRS1220 or AZ11645373, selective A3R or P2X7R antagonists, respectively, counteracted ATP antiproliferative effects. AZ11645373 also abolished the inhibitory effect of Bz-ATP low doses on GSC growth. These findings provide important clues on the anticancer potential of ligands for A3R, P2Y1R, and P2X7R, which are involved in the GSC growth control. Interestingly, ATP and BzATP potentiated the cytotoxicity of temozolomide (TMZ), currently used for GBM therapy, enabling it to cause a greater and long-lasting inhibitory effect on GSC duplication when readded to cells previously treated with purine nucleotides plus TMZ. These are the first findings identifying purine nucleotides as able to enhance TMZ antitumor efficacy and might have an immediate translational impact. 相似文献
16.
Barbarella G Zambianchi M Ventola A Fabiano E Della Sala F Gigli G Anni M Bolognesi A Polito L Naldi M Capobianco M 《Bioconjugate chemistry》2006,17(1):58-67
The synthesis of multicolor fluorescent oligothiophene N-succinimidyl esters (TSEs) is reported, and their optical properties are discussed with the aid of ab initio calculations. The esters were coupled to proteins and to 3'-amino-modified oligonucleotides in mild conditions and with similar modalities. A comparative study of the bioconjugate of IgG1 anti-CD3 antibody labeled with a blue fluorescent TSE and with fluorescein isothiocyanate (FITC) is reported, showing that the former achieves higher photoluminescence intensity and optical stability than the latter. Fluorescence resonance energy transfer experiments with TSE-labeled oligonucleotides and examples of cellular imaging via TSE-labeled proteins are reported. 相似文献
17.
Olaf Heilmayer Cornelia Honnen Ute Jacob Mariachiara Chiantore Riccardo Cattaneo-Vietti Thomas Brey 《Polar Biology》2005,28(7):523-527
Annual growth rates of Antarctic marine organisms are low compared to their relatives from warmer waters. Previous studies hypothesise that high food availability during austral spring–summer may enable Antarctic invertebrates to attain comparatively high short-term growth rates despite the low temperature. Neither a temperature-growth experiment with juvenile Adamussium colbecki (Smith 1902) nor the comparison of A. colbecki summer growth rates with an empirical scallop specific growth-to-temperature relationship could confirm this hypothesis. Hence, summer growth rates of young, immature A. colbecki are strongly affected by temperature, i.e. no uncoupling from temperature. 相似文献
18.
Regué M Izquierdo L Fresno S Piqué N Corsaro MM Naldi T De Castro C Waidelich D Merino S Tomás JM 《Journal of bacteriology》2005,187(12):4198-4206
Up to now only one major type of core oligosaccharide has been found in the lipopolysaccharide of all Klebsiella pneumoniae strains analyzed. Applying a different screening approach, we identified a novel Klebsiella pneumoniae core (type 2). Both Klebsiella core types share the same inner core and the outer-core-proximal disaccharide, GlcN-(1,4)-GalA, but they differ in the GlcN substituents. In core type 2, the GlcpN residue is substituted at the O-4 position by the disaccharide beta-Glcp(1-6)-alpha-Glcp(1, while in core type 1 the GlcpN residue is substituted at the O-6 position by either the disaccharide alpha-Hep(1-4)-alpha-Kdo(2 or a Kdo residue (Kdo is 3-deoxy-D-manno-octulosonic acid). This difference correlates with the presence of a three-gene region in the corresponding core biosynthetic clusters. Engineering of both core types by interchanging this specific region allowed studying the effect on virulence. The replacement of Klebsiella core type 1 in a highly type 2 virulent strain (52145) induces lower virulence than core type 2 in a murine infection model. 相似文献
19.
Riccardo Cattaneo-Vietti Mariachiara Chiantore Stefano Schiaparelli Giancarlo Albertelli 《Polar Biology》2000,23(3):173-182
The aim of this work is to improve the knowledge of the mollusc fauna of Terra Nova Bay (Ross Sea), on the basis of more
than 100 stations sampled from 25 to 1100 m depth, during Italian Antarctic Expeditions (austral summers 1987/1988, 1989/1990,
1993/1994, 1994/1995, 1995/1996 and 1997/1998). In shallow waters, gastropod fauna is represented by 31 species, among which
Neobuccinum eatoni, Onoba gelida, Powellisetia deserta, Philine cf. apertissima and Austrodoris kerguelenensis are the most abundant, while among bivalves (25 species) the commonest species are Adamussium colbecki, Yoldia eightsi, Laternula elliptica and “Montacuta”nimrodiana. At present, most of the Antarctic mollusc species are known as having circumantarctic distribution and are considered eurybathic.
Moreover, in general, only scarce data are available on their substrate preferences, because of their occurrence in scattered
sampling stations with different sediment features. In the present study carried out at Terra Nova Bay, based on a relatively
high number of stations, a clear zonation of mollusc assemblages is shown, according to depth and sediment features. While
gastropods characterise the superficial algal belts dominated by the red algae Iridaea cordata and Phyllophora antarctica, bivalve distribution is wider. Adamussium colbecki is the dominant species in the upper 100 m, both on soft and hard bottoms, if the slope is suitable (density up to 40–60
ind./m2). On coarse sands, this species is frequently accompanied by L. elliptica (density <20 ind./m2), while Y. eightsi characterises organic- enriched bottoms (density 70–80 ind./m2). Below 200 m depth Adacnarca nitens, Limatula hodgsoni, “Montacuta”nimrodiana and Mysella gibbosa are commonly found on relatively coarse sediments, while Thyasira dearborni and Yoldiella ecaudata prefer muddy bottoms. In order to identify bivalve assemblages, multivariate analyses were applied to stations grouped into
depth ranges, sediment features and location. While shallow bathymetric ranges (25–200 m) are clearly defined, deeper clusters
of stations are more influenced by the high degree of eurybathy of most of the species and by the scattered distribution of
the sediment particle sizes.
Accepted: 18 September 1999 相似文献
20.
Daniela Casati Tamara Stampalija Konstantinos Rizas Enrico Ferrazzi Cristina Mastroianni Eleonora Rosti Mariachiara Quadrifoglio Axel Bauer 《PloS one》2014,9(4)
Couplings between uterine contractions (UC) and fetal heart rate (fHR) provide important information on fetal condition during labor. At present, couplings between UC and fHR are assessed by visual analysis and interpretation of cardiotocography. The application of computerized approaches is restricted due to the non-stationarity of the signal, missing data and noise, typical for fHR. Herein, we propose a novel approach to assess couplings between UC and fHR, based on a signal-processing algorithm termed bivariate phase-rectified signal averaging (BPRSA).