1,721,026 research outputs found
Dall’accessibilità alle accessibilità: il disegno per l’inclusione molteplice del patrimonio culturale
No full textQuesto contributo prende le mosse dalla rinnovata accezione di accessibilità che, superato l’approccio teso alla risoluzione delle sole problematiche tangibili presenti nello spazio architettonico o nei contesti ambientali, è oggi orientata a superare l’insieme delle condizioni che, in relazione alla presenza di barriere di diversa natura, ostacolano la piena partecipazione delle persone nella società. All’interno di questo contesto, definito sia dalle prassi metodologiche di riferimento per il conseguimento di una reale accessibilità del patrimonio culturale sia da un’accezione ampliata della persona con disabilità che considera le abilità di funzionamento di ciascun individuo, il contributo proposto si pone un duplice obiettivo. Da un lato, la ricerca indaga il caso studio costituito dalla città di Perugia, partendo dalla mappatura delle effettive condizioni di accessibilità dei luoghi di interesse culturale che hanno già investito in politiche per la disabilità. Dall’altro alto, lo studio individua un sistema di strategie di indirizzo e di soluzioni volte al potenziamento della fruizione del patrimonio culturale e fondate su una pluralità di linguaggi oltre che sull’utilizzo delle tecnologie digitali, applicando la metodologia progettuale a una realtà museale del territorio umbro mediante una proposta concreta di potenziamento dell’accessibilità che tenga conto delle differenti abilità degli utenti, con particolare riferimento alle situazioni di vulnerabilità della comunicazione.This contribution takes its starting point from the renewed meaning of accessibility that, having gone beyond the approach aimed at solving only the tangible problems present in architectural space or environmental contexts, is now oriented towards overcoming the set of conditions that, in relation to the presence of barriers of various kinds, hinder the full participation of people in society. Within this context, defined by the methodological reference practices for achieving actual accessibility of cultural heritage and by an expanded understanding of the person with disability that considers the functioning abilities of everyone, the proposed contribution has a twofold objective. On the one hand, the research investigates the case study constituted by the city of Perugia, starting from the mapping of the actual conditions of accessibility of the places of cultural interest that have already invested in disability policies. On the other hand, the study identifies a system of guiding strategies and solutions aimed at enhancing the fruition of the cultural heritage and based on a plurality of languages as well as on the use of digital technologies, applying the project methodology to a museum in the Umbrian territory through a concrete proposal for enhancing accessibility that takes into account the different abilities of the users, with particular reference to situations of vulnerability of communication
Perifosine plus nutlin-3 combination shows a synergistic anti-leukaemic activity.
No full textPerifosine, which belongs to the novel class of antitumoral agents alkylphospholipids, is currently undergoing phase II clinical evaluation (van Blitterswijk & Verheij, 2008). Although the mechanisms by which perifosine exerts its antineoplastic activity need to be fully elucidated, it has been shown that perifosine inactivates the phosphatidylinositol 3-kinase/Akt pathway (van Blitterswijk & Verheij, 2008). While previous studies have demonstrated that perifosine shows cytotoxic activity against different types of haematological malignancies, when used either alone or in combination with chemotherapeutic drugs (van Blitterswijk & Verheij, 2008), its anti-leukaemic potential has not been investigated in combination with innovative compounds. Therefore, the effect of perifosine (Cayman Chemical, Ann Arbor, MI, USA) was analyzed in a panel of p53wild-type (SKW6.4, OCI, MOLM), p53mutated (BJAB, MAVER) and p53null (HL-60) cell lines, of both B lymphoid (SKW6.4, BJAB and MAVER) and myeloid (OCI, MOLM, HL-60) origin, all purchased from the American Type Culture Collection (ATCC, Manassas, VA, USA) or obtained from DSMZ (Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Braunschweig, Germany). Perifosine was used alone or in combination with nutlin-3 (Cayman Chemical), a potent and selective small molecule inhibitor of the p53-MDM2 interaction, which induces a strong non genotoxic activation of the p53 pathway (Vassilev, 2007). In preliminary experiments, perifosine alone dose-dependently induced cytotoxicity, evaluated as previously described (Borgatti et al, 1997), in all leukaemic cell lines. The simultaneous addition of high concentrations of perifosine plus nutlin-3 (10 μmol/l each) induced a significant (P < 0·05) increase of cytotoxicity with respect to each agonist used alone in p53wild-type SKW6.4, OCI and MOLM cell lines, but not in p53mutated BJAB and MAVER and p53null cell lines, with the exception of MAVER cell line at 24 h. In order to evaluate whether the combined effect of perifosine plus nutlin-3 was synergistic, cultures were treated with serial concentrations of perifosine and nutlin-3 at a constant perifosine:nutlin-3 ratio, for 24 and 48 h and data were analyzed by the method of Chou and Talalay (1984). Synergy of perifosine plus nutlin-3 combination treatment (average combination index values <1) was clearly observed in all p53wild-type cell lines. Similarly, perifosine plus nutlin-3 (10 μmol/l each) induced enhanced cytotoxicity with respect to the treatments with the single agents also in some cases of p53wild-type primary acute myeloid leukaemia (AML, M1 and M5 type) and B chronic lymphocytic leukaemia (B-CLL) samples, but not in p53mutated or p53null cell lines. In order to investigate the molecular basis for the synergistic activity exerted by the combination of perifosine plus nutlin-3 in p53wild-type leukaemic cell lines, we have performed Western blot analysis to examine changes in the protein levels of p53 and of its major transcriptional targets (p21, Bax, MDM2), as well as MDM4/MDMX, an homolog of MDM2 which plays a non-redundant role with respect to MDM2 in down-regulating the activity of p53 and is not a transcriptional target of p53 (Meulmeester & Jochemsen, 2008). Nutlin-3 alone induced a marked accumulation of p53 protein, which was not affected by the concomitant presence of perifosine. In parallel, nutlin-3 induced an early and robust induction of both p21 and Bax, which started at 6 h and lasted for the duration of the experiment (48 h). Of note, the accumulation of both p21 and Bax was significantly potentiated by the concomitant treatment with perifosine. On the contrary, the combination of perifosine plus nutlin-3 induced completely different effects on MDM2 and MDM4/MDMX. In fact, while nutlin-3 alone significantly up-regulated the levels of expression of MDM2, which represents a major transcriptional target of p53 (Vassilev, 2007), the simultaneous addition of perifosine significantly counteracted the nutlin-3-mediated induction of MDM2. At variance to MDM2, nutlin-3 not only did not induce MDM4/MDMX, but rather promoted its degradation, an effect that is considered an important part of the mechanism of action of nutlin-3-mediated cytotoxicity (Secchiero et al, 2008). Of interest, the combination of perifosine plus nutlin-3 resulted in a more rapid degradation of MDM4/MDMX with respect to cultures treated with nutlin-3 alone.
The sustained increase in Bax protein levels observed in response to the nutlin-3 plus perifosine combination with respect to nutlin-3 alone strongly suggests that Bax induction probably represents a major molecular mechanism mediating the combined cytotoxicity of nutlin-3 plus perifosine. However, other apparently more subtle effects of the nutlin-3 plus perifosine combination were also noticed. The induction of MDM2, which represents a major transcriptional target and a key negative regulator of p53, was significantly weaker in cultures treated with nutlin-3 plus perifosine with respect to cultures treated with nutlin-3 alone. As p53 protein showed a comparable accumulation in samples treated with nutlin-3 or with nutlin-3 plus perifosine, and the best characterized mechanism of action of MDM2 is to down-regulate the transcriptional activity of p53 (Vassilev, 2007), the weaker induction of MDM2 in cultures treated with perifosine plus nutlin-3 probably accounts for the increased levels of other p53 transcriptional targets, p21 and Bax in SKW6.4 cells treated with the drug combination. A likely explanation for the differential ability of perifosine plus nutlin-3 to super-induce p21 and Bax while counteracting the accumulation of MDM2 is that perifosine blocks the Akt pathway (van Blitterswijk & Verheij, 2008), which has an important role in stabilizing both MDM2 (Zhou et al, 2001) and MDM4/MDMX (Secchiero et al, 2008). In this respect, also the ability of perifosine to potentiate the nutlin-3-mediated down-regulation of MDM4/MDMX is particularly noteworthy since it demonstrated that the levels of MDM4/MDMX represent a major molecular determinant in the cytotoxic response to nutlin-3, at least in solid tumours (Secchiero et al, 2008). In conclusion, our present study suggests that the combined treatment of perifosine plus nutlin-3 might offer a novel therapeutic strategy for p53wild-type haematological malignancies, which represent >80% of all haematological malignancies at diagnosis (Mitani et al, 2007)
Role of full-length osteoprotegerin in tumor cell biology.
No full textOsteoprotegerin (OPG) is a soluble tumor necrosis factor receptor family member, which potently inhibits RANKL-mediated osteoclastogenesis. Numerous constructs have been created for therapeutic purposes in which the heparin-binding and death homology domains of OPG were removed and the remaining peptide (amino acids 22-194) was fused to the Fc domain of human IgG1 (OPG-Fc). The administration of OPG-Fc efficiently counteracted bone loss in a variety of preclinical models of cancers. However, several in vitro studies have shown that native or recombinant full-length OPG not only neuralizes RANKL, but also the death-inducing ligand TRAIL, suggesting that OPG might potentially counteract the anti-tumor activity of TRAIL. Additional evidence suggests that full-length OPG possesses RANKL- and TRAIL-independent biological properties, mainly related to the promotion of endothelial cell survival and angiogenesis. Finally, breast tumor cells overexpressing OPG have shown increased bone metastatic potential in vivo. The relevance of these apparently conflicting findings in tumor cell biology is highlighted
SOCS1 is significantly up-regulated in Nutlin-3-treated p53 wild-type B chronic lymphocytic leukemia (BCLL) samples and shows an inverse correlation with miR-155
No full textThe basal SOCS1 mRNA levels were significantly lower in p53 mutated BJAB and MAVER leukemic cell lines with respect to p53 wild-type SKW6.4 and JVM-2 leukemic cell lines, p53 wild-type primary B chronic lymphocytic leukemia (B-CLL) cells and primary normal peripheral blood mononuclear cells (PBMC). Moreover, the MDM2 small molecule inhibitor Nutlin-3 significantly increased the levels of SOCS1 mRNA in both primary p53wild-type B-CLL cells as well as in p53 wild-type B leukemic cell lines, but not in p53mutated B leukemic cell lines nor in primary PBMC. Of note, a significant inverse correlation was observed between SOCS1 mRNA and miR-155 levels in Nutlin-3-treated primary B-CLL cells and PBMC, suggesting that the miRNA-155/SOCS1 axis represents a potentially important therapeutic target of Nutlin-3 in B-CLL. © 2012 Springer Science+Business Media, LLC
Decreased levels of soluble TNF-related apoptosis-inducing ligand (TRAIL) in the conjunctival sac fluid of patients with diabetes affected by proliferative retinopathy.
No full textThese data demonstrates for the first time that patients with
proliferative diabetic retinopathy are characterized by decreased levels of soluble TRAIL in the conjunctival sac fluid. Although
the relationship between soluble TRAIL released in the
conjuctival sac fluid and TRAIL expressed in the retina or in
the vitreous body are not known, our study strengthens the
notion that TRAIL plays an important anti-inflammatory role in
the eye. In addition, neither the duration of diabetes mellitus,
nor the levels of glycated haemoglobin or the type of
medications had significant impact on the levels of TRAIL
measured in the conjunctival sac. In light of previous findings, it is plausible to suppose that a decreased production and ⁄ or
release of TRAIL might contribute to worsening proliferative
diabetic retinopathy by reducing the degree of apoptosis in
retinal endothelial cells
The oncogene DEK promotes leukemic cell survival and is downregulated by both Nutlin-3 and chlorambucil in B-chronic lymphocytic leukemic cells.
No full textThe response of human natural killer cells to interleukin-2.
No full textNatural killer cells play a key role in the defence of organisms against virus infections and in the control of tumor onset. Interleukin-2 is a multifunctional inflammatory cytokine able to activate natural killer cells, essentially inducing cell proliferation, lymphokine-activated-killer cell generation and cytokine production. Here we discuss some signaling events generated by interleukin-2 in the cell nucleus of primary human natural killer cells, specifically focusing on the lipid signal transduction and the induction of the cyclic adenosine-5'-monophosphate response element binding protein transcription factor. The implications of these nuclear events in the response of natural killer cells to interleukin-2 are also discussed
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and TNF-α promote the NF-κB-dependent maturation of normal and leukemic myeloid cells
No full textTumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and TNF-alpha induced monocytic maturation of primary normal CD34-derived myeloid precursors and of the M2/M3-type acute myeloid leukemia HL-60 cell line, associated to increased nuclear factor (NF)-B activity and nuclear translocation of p75, p65, and p50 NF-B family members. Consistently, both cytokines also induced the degradation of the NF-B inhibitors, IB and IB, and up-regulated the surface expression of TRAIL-R3, a known NF-B target. However, NF-B activation and IB degradation occurred with different time-courses, since TNF-alpha was more potent, rapid, and transient than TRAIL. Of the two TRAIL receptors constitutively expressed by HL-60 (TRAIL-R1 and TRAIL-R2), only the former was involved in IB degradation, as demonstrated by using agonistic anti-TRAIL receptor antibodies. Moreover, NF-B nuclear translocation induced by TRAIL but not by TNF-alpha was abrogated by z-IETD-fmk, a caspase-8-specific inhibitor. The key role of NF-B in mediating the biological effects of TNF-alpha and TRAIL was demonstrated by the ability of unrelated pharmacological inhibitors of the NF-B pathway (parthenolide and MG-132) to abrogate TNF-alpha and TRAIL-induced monocytic maturation. These findings demonstrate that NF-B is essential for monocytic maturation and is activated via distinct pathways, involving or not involving caspases, by the related cytokines TRAIL and TNF-alpha
The MDM2 inhibitor Nutlin-3 attenuates streptozotocin-induced diabetes mellitus and increases serum level of IL-12p40.
No full textBesides its well-established oncosuppressor activity, a key function of p53 in regulating metabolic pathways has been recently identified. Nevertheless, the role of p53 with respect to diabetes mellitus (DM) appears highly controversial. To address this issue, we have used the cis-imidazoline compound Nutlin-3, an inhibitor of MDM2/p53 interaction, which represents a potent and selective non-genotoxic activator of the p53 pathway both in in vivo and in vitro experimental settings. Experimental DM was induced by intraperitoneal injections of low concentrations of streptozotocin (STZ) in C57BL/6N mice (n = 20). A group of control vehicle-injected mice (n = 10) and of STZ-treated mice (n = 10) was co-injected with Nutlin-3. Mice co-injected with STZ + Nutlin-3 exhibited attenuated features of DM with respect to animals treated with STZ alone. Indeed, STZ + Nutlin-3-treated mice were characterized by significantly (p < 0.05) lower levels of hyperglycemia, reduced weight loss, and increased spleen weight. In addition, STZ alone promoted a marked decrease in the levels of several circulating cytokines, including interleukin-12 (IL-12)p40. On the other hand, co-injection of STZ + Nutlin-3 significantly (p < 0.01) counteracted IL-12p40 down-modulation. In vitro experiments performed on the RAW264.7 macrophagic cell line model, used as cellular source of IL-12p40, demonstrated that Nutlin-3 treatment increased IL-12p40 release, strongly suggesting a direct effect of Nutlin-3 on the immune system. Overall, these data demonstrate that systemic administration of Nutlin-3 ameliorates the severity of STZ-induced DM and increases the levels of circulating IL-12p40
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