1,290 research outputs found
Inhibition of p38 MAP kinase pathway induces apoptosis and prevents Epstein Barr virus reactivation in Raji cells exposed to lytic cycle inducing compounds
No full textBackground: EBV lytic cycle activators, such as phorbol esters, anti-immunoglobulin, transforming growth factor b (TGFb), sodium butyrate, induce apoptosis in EBV-negative but not in EBV-positive Burkitt's lymphoma (BL) cells. To investigate the molecular mechanisms allowing EBV-infected cells to be protected, we examined the expression of viral and cellular antiapoptotic proteins as well as the activation of signal transduction pathways in BL-derived Raji cells exposed to lytic cycle inducing agents. Results: Our data show that, following EBV activation, the latent membrane protein 1 (LMP1) and the cellular anti-apoptotic proteins MCL-1 and BCL-2 were quickly up-regulated and that Raji cells remained viable even when exposed simultaneously to P(BU)(2), sodium butyrate and TGFb. We report here that inhibition of p38 pathway, during EBV activation, led to a three fold increment of apoptosis and largely prevented lytic gene expression. Conclusion: These findings indicate that, during the switch from the latent to the lytic phase of EBV infection, p38 MAPK phosphorylation plays a key role both for protecting the host cells from apoptosis as well as for inducing viral reactivation. Because Raji cells are defective for late antigens expression, we hypothesize that the increment of LMP1 gene expression in the early phases of EBV lytic cycle might contribute to the survival of the EBV-positive cells
Epstein-Barr virus lytic cycle activation alters proteasome subunit expression in Burkitt's lymphoma cells
No full textWe have shown that Epstein-Barr virus (EBV) lytic cycle activation in Burkitt's lymphoma (BL) cells down-regulates chymotrypsin- and caspase-like activities of the proteasome. The aim of the present study was to evaluate whether EBV activation might also affect proteasome subunit composition. Our results indicate that, independently of the latency program established in the host cells, induction of the EBV lytic cycle reduces the expression of the proteasomal components beta 5, beta 1 and beta 2i, whereas it increases that of beta 2, beta 1i, PA28 alpha and PA28 beta. The modulation of the composition and enzymatic activities of the proteolytic complex are indicative of a less efficient generation of viral immunoepitopes
Giulia Veronica Varisco
No full textThe headword explains the biography and the contribution of the author Giulia Varisco to the children's literatur
TTV and other anelloviruses: The astonishingly wide spread of a viral infection
No full textThe broad family of viruses known as anelloviruses (AV) infects both humans and numerous animal species. They have a tiny, covalently closed single-stranded DNA genome and the astonishing capacity to infect a very high percentage of healthy and ill people with chronic infections that could last a lifetime. AV, and particularly the prototype Torquetenovirus, have established a successful interaction with the host's immune system and the rate at which they replicate is a gauge to measure overall immune function, even though many aspects of their life cycle and pathogenesis are still poorly understood
Ytterbium Disilicate/Monosilicate Multilayer Environmental Barrier Coatings: Influence of Atmospheric Plasma Spray Parameters on Composition and Microstructure
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Ytterbium Disilicate/Monosilicate Multilayer Environmental Barrier Coatings: Influence of Atmospheric Plasma Spray Parameters on Composition and Microstructure
by Giulia Di Iorio,Laura Paglia *ORCID,Giulia PedrizzettiORCID,Virgilio GenovaORCID,Francesco MarraORCID,Cecilia BartuliORCID andGiovanni PulciORCID
INSTM Reference Laboratory for Materials and Surface Engineering, Sapienza University of Rome, Eudossiana 18, 00184 Rome, Italy
*
Author to whom correspondence should be addressed.
Coatings 2023, 13(9), 1602; https://doi.org/10.3390/coatings13091602
Original submission received: 10 August 2023 / Revised: 31 August 2023 / Accepted: 11 September 2023 / Published: 13 September 2023
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Abstract
SiC/SiC ceramic matrix composites (SiCf/SiC CMCs) are regarded as the new materials for the hot-section components of aircraft gas turbine engines, since they have one-third of the density of metallic superalloys, a higher temperature capability, good mechanical strength, and excellent thermal shock resistance. However, high-temperature water-vapor-rich combustion gases can induce severe surface recession phenomena in SiC/SiC leading to component failure. For this reason, it is necessary to design protective coatings, i.e., environmental barrier coatings (EBCs), able to protect the SiC/SiC surface in combustion environments. In the present work, ytterbium monosilicate (Yb2SiO5), stable when exposed to water vapor at high temperatures, and ytterbium disilicate (Yb2Si2O7), characterized by a thermal expansion coefficient closer to that of the substrate, were selected for a multilayer EBC system. EBCs were processed using the atmospheric plasma spray (APS) technique. A set of deposition parameters were tested, varying the power of the torch, and the composition and microstructure of the deposited coatings were studied in terms of porosity, crack density, and post-deposition phase retention by performing SEM, EDS, and XRD analysis. The results allow for the definition of the influence of deposition parameters on the final properties of multilayer EBC coatings
Correction to: Safety and Psychological Outcomes of Tandem t:Slim X2 Insulin Pump with Control-IQ Technology in Children, Adolescents, and Young Adults with Type 1 Diabetes: A Systematic Review
No full textThe second author name was incorrectly published as Giula Maria Smylie. The correct name is Giulia Marie Smylie. The original article has been corrected
Down-regulation of proteolytic complexes following EBV activation in BL cells
No full textIn Burkitt's lymphoma cells, Epstein Barr virus (EBV) latency products interact with the ubiquitin-proteasome system to promote episomal maintenance and immunological evasion while the tripeptidylpeptidase II (TPPII) functions as an alternative protease. In the present study, we have examined the activities and levels of the proteasome and TPPII complex in Raji and in Akata cells after induction of EBV lytic cycle. The results show that the chymotrypsin-like and caspase-like activities of the proteasome were substantially reduced in Raji and Akata cells. Similarly, TPPII activity was diminished in both cell lines but was recovered in Akata cells at longer time after induction. Protein levels of the alpha/beta subunits of the 20S proteasome and TPPII concentration decreased to different extents after EBV activation, whereas the ubiquitin binding S6' subunit of the 19S regulatory complex increased three to fourfold along with the levels of ubiquitin-conjugates. Collectively, these observations demonstrate impairment of two major cellular proteolytic systems at the onset of EBV lytic infection. (c) 2006 Elsevier Inc. All rights reserved
Scrivere senza anestesia. La chiarezza di Giulia Niccolai
No full textIl saggio colloca storicamente la narratrice e poetessa Giulia Niccolai nel canone del Novecento letterario italiano discutendone poetica e cifre stilistiche. L'ampia analisi proposta tocca tutte le opere dell'autrice evidenziandone i legami intertestuali, anche tra poesia e narrativa, e i progressivi sviluppi in un arco cronologico esteso, tra anni Sessanta e primi anni Duemila. Lo studio coglie anche l'importanza dei riferimenti alle arti visive, in particolare alla fotografia, che Giulia Niccolai ha praticato in prima persona negli anni della Neoavanguardia, e alla pittura americana.The essay places the narrator and poet Giulia Niccolai in the canonical twentieth century Italian literary discussing her poetics and stylistic figures. The wide analysis proposed touches all the works of the author highlighting the intertextual links, also between poetry and narrative, and the progressive developments in an extended chronological period, between the Sixties and early Twenties. The study also captures the importance of references to the visual arts, especially photography, which Giulia Niccolai has practiced in the years of the Neo-avant-garde, and to American painting
“Modulation of NKG2D and DNAM-1 activating receptors and their ligands during HIV-1 infection”.
No full textNatural killer (NK) cells play a critical role in host defense against viral infections.
Chronic HIV-1 infection is associated with an accumulation of dysfunctional NK
cell, that unsuccessfully control viral replication. However, the underlying
mechanisms for this NK cell dysfunction are poorly understood.
NK cells do not express an antigen
specific receptor, as do other lymphocytes. Instead, NK cells encode a variety of
different activating and inhibitory receptors and NK cell activation is dependent on a
delicate balance between signals of opposite sign elicited by the multiple NK cell
receptor–ligand interactions that follow NK cell–target cell interaction.
The goal of my PhD project was to analyze the role of NK cell activating pathways
upon HIV-1 infection.
Specifically, I studied the modulation of the activating receptor NKG2D with
particular interest on the mechanism of release, namely shedding, of its ligands
(NKG2DLs) during HIV-1 infection in in vitro cell systems as well as in HIVinfected
patients.
Moreover, I investigated the modulation by viral proteins, such as Nef and Vpu, of
PVR (Poliovirus Receptor, CD155, Necl-5) a ligand for another stimulatory
receptor, DNAM-1 (DNAX accessory molecule-1 or CD226).The final goal of this work was to identify novel factors that regulate the function of
immune responses against HIV-1 and that could provide new prognostic biomarkers
and innovative antiviral strategies.The work was supported by grants of the Italian Ministry of Health, Programma
Nazionale di Ricerca sull’AIDS’ in collaboration with ISS and Ricerca Corrente 2010 cofunded by the Italian 5 x 1000 contribution 2008 and by grants of the Italian
Association for Cancer Research (AIRC), the Italian Ministry of University and Research
(MIUR), and the “Sapienza” University of Rome, Ital
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L'afrofuturismo tra Stati Uniti e Italia. Dalla memoria storica ai viaggi intergalattici per re-immaginare futuri postumani
No full textIn this article the author explores the cultural movement called Afrofuturism, tracing its origins, features, simbology, and its historical and political meanings. Starting from the (supposed) discoursive gap between African and African American people on one side and technology and science fiction on the other, this paradigm addresses themes related to the intersection of African Diaspora and African cultures with technology and science fiction, with the aim to recover the history of slavery and racism through the projections into alternative space-time contexts. In particular, the author explores the feminist afrofuturism perspective in order to examine the specific oppression and cultural production of African and African American women. In doing so, the author analyzes the development of afrofuturism in Italy, focusing on the work of the singer and beatmaker Karima 2G
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