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41.
C Drullion C Tr��goat V Lagarde S Tan R Gioia M Priault M Djavaheri-Mergny A Brisson P Auberger F-X Mahon J-M Pasquet 《Cell death & disease》2012,3(8):e373
Imatinib, the anti-Abl tyrosine kinase inhibitor used as first-line therapy in chronic myeloid leukemia (CML), eliminates CML cells mainly by apoptosis and induces autophagy. Analysis of imatinib-treated K562 cells reveals a cell population with cell cycle arrest, p27 increase and senescence-associated beta galactosidase (SA-β-Gal) staining. Preventing apoptosis by caspase inhibition decreases annexin V-positive cells, caspase-3 cleavage and increases the SA-β-Gal-positive cell population. In addition, a concomitant increase of the cell cycle inhibitors p21 and p27 is detected emphasizing the senescent phenotype. Inhibition of apoptosis by targeting Bim expression or overexpression of Bcl2 potentiates senescence. The inhibition of autophagy by silencing the expression of the proteins ATG7 or Beclin-1 prevents the increase of SA-β-Gal staining in response to imatinib plus Z-Vad. In contrast, in apoptotic-deficient cells (Bim expression or overexpression of Bcl2), the inhibition of autophagy did not significantly modify the SA-β-Gal-positive cell population. Surprisingly, targeting autophagy by inhibiting ATG5 is accompanied by a strong SA-β-Gal staining, suggesting a specific inhibitory role on senescence. These results demonstrate that in addition to apoptosis and autophagy, imatinib induced senescence in K562 CML cells. Moreover, apoptosis is limiting the senescent response to imatinib, whereas autophagy seems to have an opposite role. 相似文献
42.
Circulating hematopoietic progenitor cells in runners. 总被引:1,自引:0,他引:1
Maria R Bonsignore Giuseppe Morici Alessandra Santoro Maria Pagano Lucia Cascio Anna Bonanno Pietro Abate Franco Mirabella Mirella Profita Giuseppe Insalaco Maria Gioia A Maurizio Vignola Ignazio Majolino Ugo Testa James C Hogg 《Journal of applied physiology》2002,93(5):1691-1697
Because endurance exercise causes release of mediators and growth factors active on the bone marrow, we asked whether it might affect circulating hematopoietic progenitor cells (HPCs) in amateur runners [n = 16, age: 41.8 +/- 13.5 (SD) yr, training: 93.8 +/- 31.8 km/wk] compared with sedentary controls (n = 9, age: 39.4 +/- 10.2 yr). HPCs, plasma cortisol, interleukin (IL)-6, granulocyte colony-stimulating factor (G-CSF), and the growth factor fms-like tyrosine kinase-3 (flt3)-ligand were measured at rest and after a marathon (M; n = 8) or half-marathon (HM; n = 8). Circulating HPC counts (i.e., CD34(+) cells and their subpopulations) were three- to fourfold higher in runners than in controls at baseline. They were unaffected by HM or M acutely but decreased the morning postrace. Baseline cortisol, flt3-ligand, IL-6, and G-CSF levels were similar in runners and controls. IL-6 and G-CSF increased to higher levels after M compared with HM, whereas cortisol and flt3-ligand increased similarly postrace. Our data suggest that increased HPCs reflect an adaptation response to recurrent, exercise-associated release of neutrophils and stress and inflammatory mediators, indicating modulation of bone marrow activity by habitual running. 相似文献
43.
Lack of CD27-CD45RA-V gamma 9V delta 2+ T cell effectors in immunocompromised hosts and during active pulmonary tuberculosis. 总被引:5,自引:0,他引:5
Cristiana Gioia Chiara Agrati Rita Casetti Cristiana Cairo Giovanna Borsellino Luca Battistini Giorgio Mancino Delia Goletti Vittorio Colizzi Leopoldo P Pucillo Fabrizio Poccia 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(3):1484-1489
In humans, the circulating pool of mycobacteria-reactive Vgamma9Vdelta2+ T cells is expanded with age and may contribute to Mycobacterium tuberculosis immunosurveillance. We observed that two subsets of Vgamma9Vdelta2+ T cells could be identified on the basis of CD27 expression in immunocompetent adults, showing that functionally differentiated gammadelta T cells have lost CD27 expression. In contrast, the CD27-CD45RA-Vgamma9Vdelta2+ T cell subset of effector cells was absent in cord blood cells from healthy newborns and lacking in the peripheral blood from HIV-infected patients. Moreover, circulating Vgamma9Vdelta2+ T cell effectors were significantly reduced in patients with acute pulmonary tuberculosis, resulting in a reduced frequency of IFN-gamma-producing cells after stimulation with nonpeptidic mycobacterial ligands. These observations indicate that monitoring and boosting gammadelta T cell effectors could be clinically relevant both in immunocompromised hosts and during active tuberculosis disease. 相似文献
44.
Minh H. Dinh Meegan R. Anderson Michael D. McRaven Gianguido C. Cianci Scott G. McCoombe Z. L. Kelley Casey J. Gioia Angela J. Fought Alfred W. Rademaker Ronald S. Veazey Thomas J. Hope 《PLoS pathogens》2015,11(3)
To gain insight into female-to-male HIV sexual transmission and how male circumcision protects against this mode of transmission, we visualized HIV-1 interactions with foreskin and penile tissues in ex vivo tissue culture and in vivo rhesus macaque models utilizing epifluorescent microscopy. 12 foreskin and 14 cadaveric penile specimens were cultured with R5-tropic photoactivatable (PA)-GFP HIV-1 for 4 or 24 hours. Tissue cryosections were immunofluorescently imaged for epithelial and immune cell markers. Images were analyzed for total virions, proportion of penetrators, depth of virion penetration, as well as immune cell counts and depths in the tissue. We visualized individual PA virions breaching penile epithelial surfaces in the explant and macaque model. Using kernel density estimated probabilities of localizing a virion or immune cell at certain tissue depths revealed that interactions between virions and cells were more likely to occur in the inner foreskin or glans penis (from local or cadaveric donors, respectively). Using statistical models to account for repeated measures and zero-inflated datasets, we found no difference in total virions visualized at 4 hours between inner and outer foreskins from local donors. At 24 hours, there were more virions in inner as compared to outer foreskin (0.0495 +/− 0.0154 and 0.0171 +/− 0.0038 virions/image, p = 0.001). In the cadaveric specimens, we observed more virions in inner foreskin (0.0507 +/− 0.0079 virions/image) than glans tissue (0.0167 +/− 0.0033 virions/image, p<0.001), but a greater proportion was seen penetrating uncircumcised glans tissue (0.0458 +/− 0.0188 vs. 0.0151 +/− 0.0100 virions/image, p = 0.099) and to significantly greater mean depths (29.162 +/− 3.908 vs. 12.466 +/− 2.985 μm). Our in vivo macaque model confirmed that virions can breach penile squamous epithelia in a living model. In summary, these results suggest that the inner foreskin and glans epithelia may be important sites for HIV transmission in uncircumcised men. 相似文献
45.
In this paper we propose a method to produce maps of fire danger index (FDI). The index includes in the formula a vegetation pyrogenic potential index (VPPI) based on floristic phytosociological data. The map of FDI is produced by integrating available phytosociological maps of vegetation, geomorphology and climate, using the Geographic Information System technology. The method is applied to an area of the coastal Classical Karst (NE-Italy). While fire risk maps based on the incidence of previous fires are useful for facilitating emergency operations, e.g. the allocation of fire fighting resources, we conclude that the proposed index offers an effective tool to plan actions for fire prevention. 相似文献
46.
Claudia Alquati Luca De Gioia Gianluca Santarossa Lilia Alberghina Piercarlo Fantucci Marina Lotti 《European journal of biochemistry》2002,269(13):3321-3328
A recombinant lipase cloned from Pseudomonas fragi strain IFO 3458 (PFL) was found to retain significant activity at low temperature. In an attempt to elucidate the structural basis of this behaviour, a model of its three-dimensional structure was built by homology and compared with homologous mesophilic lipases, i.e. the Pseudomonas aeruginosa lipase (45% sequence identity) and Burkholderia cepacia lipase (38%). In this model, features common to all known lipases have been identified, such as the catalytic triad (S83, D238 and H260) and the oxyanion hole (L17, Q84). Structural modifications recurrent in cold-adaptation, i.e. a large amount of charged residues exposed at the protein surface, have been detected. Noteworthy is the lack of a disulphide bridge conserved in homologous Pseudomonas lipases that may contribute to increased conformational flexibility of the cold-active enzyme. 相似文献
47.
48.
Giancarlo Gioia Lobbia Claudio Pettinari Brian W. Skelton 《Inorganica chimica acta》2005,358(13):3633-3641
New silver(I) derivatives [Ag{HnB(btz)4 − n}(PR3)x] (n = 1 or 2, x ranging from 1 to 3), containing monodentate tertiary phosphines and anionic poly(benzotriazol-1-yl)borates, have been prepared from the reaction of AgNO3 with PR3 (R = Ph, o-tolyl, m-tolyl, p-tolyl, Bns) and K[H2B(btz)2], or K[HB(btz)3] (Hbtz = 1,2,3-benzotriazole). When the reaction between K[H2B(btz)2] and AgNO3 was carried out in the presence of dppe (1,2-bis(diphenylphosphino)ethane), or dppf (1,1′-bis(diphenylphosphino)ferrocene), compounds [Ag{H2B(btz)2}]2(L) (L = dppe or dppf) formed, the diphosphine acting as a bidentate bridging P2-donor. Solid state and solution properties of all complexes have been investigated through analytical and spectroscopic measurements (IR, 1H, 31P NMR), the 1H and 31P NMR spectra being interpreted in terms of equilibria that involve mono- and di-nuclear complexes. Adducts [Ag{HB(btz)3}(PPh3)3] · (1/2H2O) and [Ag{H2B(btz)2}]2 (dppf) have been characterised by single crystal X-ray studies. In the former, the HB(btz)3 is unidentate in an NAgP3 coordination environment; the latter is a dimer, the dppf bridging the two silver atoms, while the H2B(btz)2 ligand, which chelates one silver, bridges to the second also, the array having 2-symmetry. 相似文献
49.
Giancarlo Gioia Lobbia Claudio Pettinari Carlo Santini Brian W. Skelton 《Inorganica chimica acta》2005,358(4):1162-1170
New silver (I) derivatives containing monodentate tertiary phosphanes and anionic poly(triazol-1-yl)borate ligands have been prepared from the reaction of AgNO3 and PR3 (R = Ph, Bn, o-tolyl, m-tolyl, p-tolyl) and potassium dihydrobis(1,2,4-triazolyl)borate, K[H2B(tz)2], or potassium hydrotris(1,2,4-triazolyl)borate, K[HB(tz)3]; their solid state and solution properties have been investigated through analytical and spectroscopic measurements (IR, 1H-, and 31P NMR). The 1H- and 31P NMR solution spectra in some cases can be interpreted on the basis of a dissociation of [{H2B(tz)2}Ag(PR3)2] into [{H2B(tz)2}Ag(PR3)] and PR3. All the compounds are soluble in chlorinated solvents and are non-electrolytes in CH2Cl2 and acetone solutions. [{H2B(tz)2}Ag(PPh3)2] and [{H2B(tz)2}Ag{P(m-tolyl)3}2] are simple mononuclear arrays, the silver atoms lying in four-coordinate N2AgP2 environments. Owing to the presence of the methyl substituents on the phosphane ligand, the complex [{HB(tz)3}Ag{P(o-tolyl)3}], as expected, is mononuclear. In [{H2B(tz)2}Ag{P(p-tolyl)3}], the silver environment is still four-coordinate but PAgN3, utilizing the coordinating capability of one of the additional (‘exo’-) ring nitrogens not only to complete the four-coordinate array about the silver but, necessarily, to link successive asymmetric units into a single-stranded polymer. 相似文献
50.
Paolo Mereghetti Maria Luisa Ganadu Elena Papaleo Piercarlo Fantucci Luca De Gioia 《BMC bioinformatics》2008,9(1):66