1,290 research outputs found
C. DE MITRI, G. MASTRONUZZI, D. TAMIANO, La ceramica a vernice nera nel bacino ionio-adriatico tra produzioni locali ed importazioni: la penisola salentina, in I. Kamenjarin, M. Ugarković (Hrsg.), Exploring the Neighborhood. The Role of Ceramics in Understanding Place in the Hellenistic World, Proceedings of the 3rd Conference of IARPotHP, Kaštela, June 2017, 1st – 4th, (IARPotHP 3), Wien 2020, (ISBN 978-3-85161-237-0), pp. 395-410 (il sottoscritto è autore delle pp. 398-402).
No full textDuring the late Hellenistic age, flourishing workshops produced pottery that circulated through short-range trading routes in the areas around the Ionian-Adriatic basin. There were
many black gloss ware workshops on the opposite shores, and we can recognize different regional productions. This kind of tableware is typical of the pre-Roman period but it was produced until the late Republican age and, sometimes, also in the early Roman Imperial age. Also in the Salento peninsula, some ateliers have been identified, thanks to kilns remains or other production indicators. In particular, this paper aims to discuss the data from the settlement of Vaste, inland of Otranto, and to propose an analysis of different shapes of black gloss ware in relation to different find contexts
Erratum to: Compartmentalized activities of the pyruvate dehydrogenase complex sustain lipogenesis in prostate cancer (Nature Genetics, (2018), 50, 2, (219-228), 10.1038/s41588-017-0026-3)
No full textIn the HTML version of this article initially published, the name of author Diletta Di Mitri was miscoded in the XML such that Di was included as part of the given name instead of the family name. The error has been corrected in the HTML version of the article
Studio delle caratteristiche fenotipiche e funzionali di sottopopolazioni linfocitarie immunomodulatorie in pazienti affetti da sclerosi multipla
No full textLa sclerosi multipla è una patologia infiammatoria demielinizzante che colpisce il sistema nervoso centrale. Un’ipotesi generalmente condivisa è quella secondo la quale alterazioni a carico della composizione e della funzionalità dei linfociti T regolatori possano essere implicate nel processo autoimmune che contribuisce alla patogenesi della malattia. Ad oggi molteplici gruppi hanno riscontrato cambiamenti nel fenotipo e nella frequenza dei linfociti regolatori in pazienti affetti da sclerosi multipla. Sebbene negli ultimi anni il mondo scientifico abbia dedicato un notevole impegno allo studio dei linfociti T regolatori, la caratterizzazione funzionale nonché il chiarimento dei meccanismi attraverso i quali queste cellule esercitano la loro attività soppressoria non sono ancora stati ben compresi.
Il presente studio si inserisce in questo ambito e nasce con lo scopo di approfondire la conoscenza dei linfociti T regolatori negli individui sani e in pazienti affetti da sclerosi multipla. Abbiamo dunque riscontrato come la popolazione CD4+CD25high caratterizzata da attività soppressoria, sia contraddistinta nell’uomo dall’espressione del CD39, un enzima appartenente alla famiglia delle nucleosidi trifosfato difosfoidrolasi, che idrolizzano i nucleotidi extracellulari nei rispettivi nucleosidi. La scissione dell’ATP da parte del CD39 avvia una reazione che si conclude con la produzione di adenosina, una molecola dalle spiccate proprietà anti-infiammatorie.
L’applicazione dell’analisi citofluorimetrica a pazienti affetti da sclerosi multipla nella forma recidivante - remittente ha rivelato una diminuzione significativa della frazione regolatoria CD4+CD25highCD39+ nel sangue periferico dei pazienti monitorati. Al fine di definire eventuali correlazioni esistenti tra le caratteristiche fenotipiche e funzionali dei linfociti T regoaltori e lo stato clinico dei pazienti e allo scopo di approfondire gli effetti esercitati su questo subset cellulare dai farmaci immunomodulatori, abbiamo poi studiato un gruppo di pazienti sottoposti a trattamento con interferon β. Abbiamo misurato la frequenza della popolazione CD4+CD25highCD39+ prima del trattamento e nel corso di un anno dall’inizio di quest’ultimo. I dati ottenuti hanno messo in luce un progressivo aumento della popolazione di linfociti regolatori; tale aumento risulta visibile già dal primo time point, e viene confermato a 6 mesi dall’inizio del trattamento.
Abbiamo infine applicato la nostra analisi ai linfociti effettori recentemente attivati che esprimono alti livelli di CD25 e sono in grado di rilasciare citochine pro-infiammatorie quali IFNgamma e IL17. L’azione svolta da queste popolazioni linfocitarie viene considerata critica nella patogenesi della sclerosi multipla, poiché esse partecipano attivamente al processo infiammatorio generato dalla risposta autoimmune. Abbiamo dunque riscontrato come la diminuzione della popolazione di linfociti T regolatori CD39+ sia controbilanciata, nei pazienti, da un aumento significativo delle popolazioni linfocitarie effettrici Th1 e Th17. Tali dati suggeriscono che nei pazienti affetti da sclerosi multipla l’equilibrio tra cellule effettrici e linfociti regolatori sia spostato verso la popolazione linfocitaria che svolge un’attività pro-infiammatoria.Multiple sclerosis is an inflammatory demielinating disease that affects the central nervous system. It is generally thought that subset composition and functional status of T regulatory lymphocytes could be implicated in the autoimmune process that contributes to its pathogenesis. Actually many groups have identified alterations in both the phenotype and frequency of Tregs in Multiple Sclerosis. Although in recent years an impressive amount of effort has been dedicated to the study of T regulatory cells (Tregs), the characterization of all the functional subsets as well as the elucidation of the mechanism by which these cells exert their suppressive function have not been yet accomplished. In particular for patients suffering of multiple sclerosis (MS) a significant decrease in the suppressive capacity of CD4+CD25high cells has been reported.
In the present study we have performed a phenotipical and functional analysis of the T regulatory compartment in healthy controls and patients affected by the relapsing remitting form of multiple sclerosis. We have found that in humans Tregs endowed with the most potent suppressive abilities express CD39, an ectoenzyme belonging to the family of nucleoside triphosphate diphosphohydrolases (NTPDase), which hydrolyze extracellular nucleotides to the respective nucleosides. Thus, extracellular ATP can be hydrolyzed to AMP and then further to adenosine, a molecule with known anti-inflammatory properties.
Interestingly, patients affected by the relapsing-remitting form of multiple sclerosis (MS) have reduced numbers of CD39+ cells within the CD4+CD25high cell population. In the attempt to define phenotypic and functional correlations with the clinical state of MS patients and to monitor the effects of immunomodulatory therapy, we have studied a cohort of MS patients undergoing treatment with β-interferon. We have measured the frequency of CD4+CD25highCD39+ cells before treatment and at 3, 6, and 9 months after the initiation of the therapy. We have found a significant increase in the fraction of CD39+ T lymphocytes already at the first time point; these data were confirmed after 6 months of therapy. We then extended our analysis to the frequency of Th1 and Th17 effector T lymphocytes, which are thought to play a fundamental role in the autoimmune process. We found that the decrease of the frequency of the CD39+ cells among the CD25high subset in these patients is reflected by an increase in the CD39- CD25high recently activated effector T cells releasing IFNγ and IL17. These data suggest that in MS patients the equilibrium between effector cells and regulatory subsets is shifted towards the proinflammatory cytokine producing cells
Endovenous laser treatment of varicose vein: a three-year personal experience
No full textVengono descritti i risultati di tre anni di esperienza di trattamento della grande e piccola safena con tecnica Laser. Early and mid term results have been promisin
Author Correction: Deep and methane-rich lakes on Titan (Nature Astronomy, (2019), 3, 6, (535-542), 10.1038/s41550-019-0714-2)
No full textHydrocarbon lakes on Titan
No full textThe Huygens Probe detected dendritic drainage-like features, methane clouds and a high surface relative humidity (∼ 50 %) on Titan in the vicinity of its landing site [Tomasko, M.G., and 39 colleagues, 2005. Nature 438, 765-778; Niemann, H.B., and 17 colleagues, 2005. Nature 438, 779-784], suggesting sources of methane that replenish this gas against photo- and charged-particle chemical loss on short (10-100) million year timescales [Atreya, S.K., Adams, E.Y., Niemann, H.B., Demick-Montelara, J.E., Owen, T.C., Fulchignoni, M., Ferri, F., Wilson, E.H., 2006. Planet. Space Sci. In press]. On the other hand, Cassini Orbiter remote sensing shows dry and even desert-like landscapes with dunes [Lorenz, R.D., and 39 colleagues, 2006a. Science 312, 724-727], some areas worked by fluvial erosion, but no large-scale bodies of liquid [Elachi, C., and 34 colleagues, 2005. Science 308, 970-974]. Either the atmospheric methane relative humidity is declining in a steady fashion over time, or the sources that maintain the relative humidity are geographically restricted, small, or hidden within the crust itself. In this paper we explore the hypothesis that the present-day methane relative humidity is maintained entirely by lakes that cover a small part of the surface area of Titan. We calculate the required minimum surface area coverage of such lakes, assess the stabilizing influence of ethane, and the implications for moist convection in the atmosphere. We show that, under Titan's surface conditions, methane evaporates rapidly enough that shorelines of any existing lakes could potentially migrate by several hundred m to tens of km per year, rates that could be detected by the Cassini orbiter. We furthermore show that the high relative humidity of methane in Titan's lower atmosphere could be maintained by evaporation from lakes covering only 0.002-0.02 of the whole surface
Electron beam generation from semiconductor photocathodes
No full textSeveral measurements on a variety of semiconductor photocathodes were performed in order to determine their photoelectric quantum efficiency. Two different excimer lasers (XeCl and KrCl) and a pulsed Xe lamp were used as light sources for electron photoextraction from doped and undoped samples of cadmiun telluride, indium antimonide, and indium phosphide. Large current densities were obtained up to the limit of the Child-Langmuir law. This suggests the use of these materials for the production of intense electron sources, which could also be used for purity measurements of noble liquids. (C) 2001 American Institute of Physics
Author Correction: A corridor of exposed ice-rich bedrock across Titan’s tropical region (Nature Astronomy, (2019), 3, 7, (642-648), 10.1038/s41550-019-0756-5)
No full textIn the version of this Article originally published, the author Rosaly Lopes was mistakenly affiliated with Northern Arizona University. Her affiliation has now been corrected to: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA. © 2019, Springer Nature Limited
Occult HBV infection in PBMCs of HIV+ individuals
No full textBackgrund and aim: Detection of HBV-DNA in HBsAg negative patients is defined as occult HBV infection. Previously, we investigated the prevalence and the genomic heterogeneity of occult HBV in the liver of 24 HIV+/HbsAg negative patients: 8 HBsAg- patients were HBV-DNA positive (33%) in the liver. HBV can be detected in PBMCs, so infected PBMCs can act as reservoirs for the cell-to-cell transmission of the virus. We aimed to determine the prevalence of occult HBV infection of peripheral blood mononuclear cells, defined as detection of sequences from ≥2 HBV genes in subjects HIV+ with HBV occult infection in the liver and to detect the viremia of HBV both in the liver than in the PBMCs. Methods: We focused on 6 HIV+ patients with occult HBV in the liver: HBV DNA levels were quantified using a real-time PCR assay based on Light Cycler technology revealed through SYBR green fluorochrome both in the liver than in PBMCs. Nested-PCR and direct sequencing were performed for S, X and PreC/Core regions. The controls were 14 HIV/HBV coinfected patients: liver+PBMCs+serum of 5 patients and serum+PBMCs of 9 patients. Results: five individuals positive for anti-HBc but negative for HBsAg had HBV DNA in their PBMCs. These 5 were also positive for HBV genomes in their liver but not in their serum. HBV-DNA, indeed, was detectable in liver, PBMCs and serum of all controls. SYBR green real-time RT-PCR showed a high level of sensitivity as the detection limit of technique was assessed at 20 HBV-DNA copies/15ng liver DNA and 20 HBV-DNA copies/300 ng DNA/10 mln cells.We found a low viremia of HBV in liver of all patients with occult infection . So in the PBMCs: 2 cases were <20 HBV-DNA copies/300 ng DNA/10 mln cells Conclusions: This study confirm previous data showing that detection of viral genomes in PBMCs may occur in the absence of viremia, antigenemia or specific viral antibodies in serum. Moreover, in the clinical setting, the most difficult parts of HBV-DNA research include the requirement of liver biopsies, and the lack of sensitive, specific and quantitative methods to detect HBV-DNA from biopsies of HBsAg negative patients. We found that the real time PCR teqnique can be applied for detection of copies of HBV in the liver and PBMCs of patients with HBV occult infectio
Deep and methane-rich lakes on Titan
No full textSaturn’s largest moon, Titan, hosts liquid hydrocarbon lakes and seas on its surface. During the last close encounter with Titan (22 April 2017), the Cassini spacecraft used its RADAR as a sounder to probe the depth of several lakes in the north polar terrain. This was the first time that Titan’s lakes, as opposed to its seas, have been viewed in a sounding configuration. Here, we show that these lakes can exceed 100 m depth and their transparency at the 2.17 cm radar wavelength indicates that they have a methane-dominated composition. This composition differs significantly from that of Ontario Lacus, the only major lake in Titan’s southern hemisphere, which is more ethane rich. If the methane-rich north polar lakes, perched hundreds of metres above the major seas, are formed by a karstic-type process, then they may drain by subsurface flow at rates between 0.001 and 1 m yr−1 (Titan year). Subsurface reservoirs and flows therefore may be an important element of the Titan geochemical system
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