1,140 research outputs found

    Genetic modification of a carcinoma with IL-4 gene increase the influx of dendridic cells relative to other cytokines

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    Tumor cells genetically modified with certain cytokine genes gain immunogenic properties that allow the development of systemic anti-tumor immunity. Whether different cytokines may influence infiltration of transduced tumors by dendritic cells (DC) has not been investigated. Therefore, we analyzed the C26 murine colon carcinoma genetically modified to release interleukin (IL)-2, IL-4, IL-12, granulocyte colony-stimulating-factor (CSF) or granulocyte-macrophage (GM)-CSF for immunostaining with the monoclonal antibody NDLC145 recognizing the DEC205 determinant which, on tumor sections, is virtually restricted to DC. Infiltrating leukocytes were also characterized for expression of co-stimulatory molecules like CD54, CD86 and major histocompatibility complex class II. The intratumoral DC content was dependent on the type of transduced cytokines with C26/IL-4 being the most abundant in DEC205+ cells. The effect of IL-4 in recruiting DC did not depend on the type of tumor since it was confirmed in the TSA mammary carcinoma. In comparison with C26/GM-CSF, C26/IL-4 had more B7.2+ cells but less Ia+ cells. Furthermore, the hypertrophic skin overlaying tumors producing GM-CSF showed numerous Langerhans cells stained by NDLC145 and the draining lymph nodes showed abundance and paucity of DC in C26/GM-CSF and C26/IL-4, respectively. When injected into the ear pinna, C26/GM-CSF stimulated, whereas C26/IL-4 inhibited DC-mediated priming of delayed-type hypersensitivity reaction by 2,4-dinitro-1-fluorobenzene. These findings prove that transduced cytokines differently influence DC recruitment at the tumor site and DC function in nearby tissues. Along with the other leukocytes and their secondary produced cytokines, DC create an environment in which T cells can be differently modulated. Such a phenomenon may have implications on genetic modification of tumor cells to be used as cancer vaccin

    Dendritic cells infiltrating tumors cotransduced with granulocytes/macrophage colony-stimulating factor (GM-CSF) and CD40 ligand genes take up and present endogenous tumor-associated antigens, and prime naive mice for a cytotoxic T-lymphocyte response.

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    We transduced BALB/c-derived C-26 colon carcinoma cells with granulocyte/macrophage colony-stimulating factor (GM-CSF) and CD40 ligand (CD40L) genes to favor interaction of these cells with host dendritic cells (DCs) and, therefore, cross-priming. Cotransduced cells showed reduced tumorigenicity, and tumor take was followed by regression in some mice. In vivo tumors were heavily infiltrated with DCs that were isolated, phenotyped, and tested in vitro for stimulation of tumor-specific cytotoxic T lymphocytes (CTLs). BALB/c C-26 carcinoma cells express the endogenous murine leukemia virus (MuLV) env gene as a tumor-associated antigen. This antigen is shared among solid tumors of BALB/c and C57BL/6 mice and contains two epitopes, AH-1 and KSP, recognized in the context of major histocompatibility complex class I molecules H-2L(d) and H-2K(b), respectively. DCs isolated from C-26/GM/CD40L tumors grown in (BALB/c X C57BL/6)F1 mice (H-2(dXb)) stimulated interferon gamma production by both anti-AH-1 and KSP CTLs, whereas tumor-infiltrating DCs (TIDCs) of BALB/c mice stimulated only anti-AH-1 CTLs. Furthermore, TIDCs primed naive mice for CTL activity as early as 2 d after injection into the footpad, whereas double-transduced tumor cells required at least 5 d for priming; this difference may reflect direct DC priming versus indirect tumor cell priming. Immunohistochemical staining indicated colocalization of DCs and apoptotic bodies in the tumors. These data indicate that DCs infiltrating tumors that produce GM-CSF and CD40L can capture cellular antigens, likely through uptake of apoptotic bodies, and mature in situ to a stage suitable for antigen presentation. Thus, tumor cell-based vaccines engineered to favor the interaction with host DCs can be considered

    CHANTI: a Fast and Efficient Charged Particle Veto Detector for the NA62 Experiment at CERN

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    The design, construction and test of a charged particle detector made of scintillation counters read by Silicon Photomultipliers (SiPM) is described. The detector, which operates in vacuum and is used as a veto counter in the NA62 experiment at CERN, has a single channel time resolution of 1.14 ns, a spatial resolution of ~2.5 mm and an efficiency very close to 1 for penetrating charged particles

    The Low Energy Tagger for the KLOE-2 experiment

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    The KLOE experiment at the upgraded DAFNE e+e- collider in Frascati (KLOE-2) is going to start a new data taking at the beginning of 2010 with its detector upgraded with a tagging system for the identification of gamma-gamma interactions. The tagging stations for low-energy e+e- will consist in two calorimeters The calorimeter used to detect low-energy e+e- will be placed between the beam-pipe outer support structure and the inner wall of the KLOE drift chamber. This calorimeter will be made of LYSO crystals readout by Silicon Photomultipliers, to achieve an energy resolution better than 8% at 200 MeV.Comment: 4 pages, 5 figures, in the proceedings of "Frontier detectors for frontier physics", isola d'Elba, Italy, May 200

    The rna-binding ubiquitin ligase mex3a affects glioblastoma tumorigenesis by inducing ubiquitylation and degradation of rig-i

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    Glioblastoma multiforme (GB) is the most malignant primary brain tumor in humans, with an overall survival of approximatively 15 months. The molecular heterogeneity of GB, as well as its rapid progression, invasiveness and the occurrence of drug-resistant cancer stem cells, limits the efficacy of the current treatments. In order to develop an innovative therapeutic strategy, it is mandatory to identify and characterize new molecular players responsible for the GB malignant phenotype. In this study, the RNA-binding ubiquitin ligase MEX3A was selected from a gene expression analysis performed on publicly available datasets, to assess its biological and still-unknown activity in GB tumorigenesis. We find that MEX3A is strongly up-regulated in GB specimens, and this correlates with very low protein levels of RIG-I, a tumor suppressor involved in differentiation, apoptosis and innate immune response. We demonstrate that MEX3A binds RIG-I and induces its ubiquitylation and proteasome-dependent degradation. Further, the genetic depletion of MEX3A leads to an increase of RIG-I protein levels and results in the suppression of GB cell growth. Our findings unveil a novel molecular mechanism involved in GB tumorigenesis and suggest MEX3A and RIG-I as promising therapeutic targets in GB

    Defective Erythrocyte Pyruvate Kinase with Impaired Kinetics and Reduced Optimal Activity

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    A unique mutant form of erythrocyte pyruvate kinase has been found associated with chronic haemolytic anaemia in a child who is apparently doubly heterozygous for the mutant isoenzyme and for pyruvate kinase deficiency of the classical quantitative type. Clinical and laboratory findings conformed closely to those typically observed in homozygous pyruvate kinase deficiency anaemia. Assayed in fresh haemolysates, the isoenzyme exhibited reduced optimal activity ( c 45% of normal) and an increased Michaelis constant for phosphoenolpyruvate (four to five times greater than normal). The kinetic anomaly was only partially corrected by activation with fructose-1,6-disphosphate. Despite some common characteristics, this isoenzyme appears distinct from others reported in the literature and lends support to the polymorphous nature of heritable baemolytic anaemias secondary to defective pyruvate kinase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73844/1/j.1365-2141.1972.tb05713.x.pd

    Break in volition: a virtual reality study in patients with obsessive-compulsive disorder

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    Research in obsessive-compulsive disorder (OCD) produced inconsistent results in demonstrating an association between patients' symptom severity and their cognitive impairments. The process involved in volition aspects of behavioral syndromes can be extensively analyzed using specific tests developed in virtual environments, more suitable to manipulate rules and possible breaks of the normal task execution with different, confusing or stopping instructions. The study involved thirty participants (15 OCD patients and 15 controls) during task execution and the relative interferences. At this purpose, the virtual version of Multiple Errands Test was used. Virtual reality setting, with a higher ecological validity respect to a classic neuropsychological battery, allowed us to take into account deficits of volition and the relative dysexecutive functions associated with OCD patients. The proposed paradigm also allows the development of innovative prototypes of coevolving technologies based on new theories and models and deeper understanding of human behavior

    Thermochemical characterization of polybenzimidazole with and without nano-ZrO2 for ablative materials application

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    During the ballistic atmospheric re-entry, a space vehicle has to withstand huge thermo-mechanical solicitations because of its high velocity and the friction with the atmosphere. According to the kind of the re-entry mission, the heat fluxes can be very high (in the order of some MW m−2) ;thus, an adequate thermal protection system is mandatory in order to preserve the structure of the vehicle, the payload and, for manned mission, the crew. Carbon phenolic ablators have been chosen for several missions because they are able to dissipate the incident heat flux very efficiently. Phenolic resin presents satisfying performance but also environmental drawbacks. Thus, a more environmental-friendly solution was conceived: a high-performance thermoplastic material, polybenzimidazole (PBI), was employed instead of phenolic resin. In this work PBI-ablative material samples were manufactured with and without the addition of nano-ZrO2 and tested with an oxyacetylene flame. For comparison, some carbon-phenolic ablators with the same density were manufactured and tested too. Thermogravimetric analysis on PBI samples was carried out at different heating rates, and the obtained TG data were elaborated to evaluate the activation energy of PBI and nano-filled PBI. The thermokinetics results for PBI show an improvement in thermal stability due to the addition of nano-ZrO2, while the oxyacetylene flame test enlightens how PBI ablators are able to overcome the carbon phenolic ablators performance, in particular when modified by the addition of nano-ZrO2

    POS0090 RISK OF QT INTERVAL PROLONGATION ASSOCIATED WITH CHRONIC USE OF HYDROXYCHLOROQUINE IN RHEUMATIC PATIENTS AND THE EFFECT OF COTREATMENTS

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    Background:Hydroxychloroquine (HCQ) has been used safely for over 60 years in rheumatic patients. However, following its recent use in covid-19 disease, its safety has been questioned, following controversial reports of cardiac toxicity1, possibly related to a prolongation of the QT interval2.Objectives:To explore the influence of chronic treatment with hydroxychloroquine on QT interval in rheumatic patients, and the possible effects of drug-to-drug interference3.Methods:12-lead electrocardiogram tracings were recorded with standard equipment in 229 ambulatory patients (SLE = 53, RA = 52, SSc = 56, UCTD = 38, Others = 30). The present analysis was performed on corrected QT intervals (QTc) calculated according to Framingham formula (QTc = QT+0.154 (1−RR)), with ULN = 449 ms in males, and 467 ms in females. Estimated glomerular filtrate rate (eGFR) was calculated from serum creatinine with the CKD-EPI equation. The influence on QTc values of demographic variables, chronic (≥3 months) HCQ treatment, and of the use of selected comedications -Statins, Angiotensin Converting Enzyme inhibitors (ACEi), Angiotensin Receptor Blockers (ARBs), Selective Serotonin Reuptake Inhibitors (SSRIs), Proton-Pump Inhibitors (PPI), Calcium Channel Blockers (CCBs) – were evaluated by parametric or non parametric statistical methods, as appropriate. All statistic al analyses were performed with the IBM SPSS statistical package version 25.Results:Table 1.Demographic and clinical variables in patients treated with HCQ (HCQ+) and in controls (HCQ-).NAgeYrs±SDFemaleN%eGFRmL/min/1.73m2StatinsN%ACEiN%ARBN%SSRIN%PPIN%CCBN%All22958.02±14.3620690.087.1418.962912.74821.8198.3146.113860.33013.1HCQ+13258.71±14.4912292.487.0020.041813.63224.2118.396.88060.61712.9HCQ-9757.51±14.308486.687.3217.471111.31616.588.255.25859.81313.4p0.5320.1830.8970.6900.1891.0000.7821.0001.000Demographic variables, and the use of evaluated comedications were not different in HCQ+ and HCQ- patients (Table 1). In the whole population, the QTc mean duration was 416.72 ± 20.70 ms, and was correlated with age (r = 0.215, p= 0.001), but not with gender (p = 0.548), eGFR (r = -0.93, p = 0.163), or disease (p = 0.092). In only 4 patients (HCQ+: 3 (2.3%) – HCQ-: 1 (1%), p = 0.639) QTc duration was above ULN.QTc duration was not associated with the use of Statins, ACEi, ARBs, or SSRIs (p = 0.454, 0.276, 0.475, and 0.131 respectively), but was significantly prolonged in patients treated with HCQ (421.26 ± 19.19 vs 410.55 ± 21.18 msec, p < 0.001), PPIs (420.57 ± 21.45 vs 410.89 ± 18.12 ms, p < 0.001), and CCBs (424.22 ± 25.97 vs 415.59 ± 19.62 ms, p < 0.033). Furthermore, as reported in Fig. 1, our data show a trend - albeit not statistically significant - towards an additive effect on QT prolongation of the association of PPIs and CCBs with HCQ, even more evident in the case of association of the 3 drug classes.Conclusion:In this study, the QTc interval was significantly prolonged in patients treated with hydroxychloroquine as compared to controls, although significant prolongation was extremely infrequent. Furthermore, our data revealed signs of drug-drug interference, suggesting that regular monitoring of the electrocardiogram is advisable in these patients, often undergoing cotreatment with multiple drugs.References:[1]Imad M. Tleyjeh, et al. The Cardiac Toxicity of Chloroquine or Hydroxychloroquine in COVID-19 Patients: A Systematic Review and Meta-regression Analysis. Mayo Clin Proc Innov Qual Outcomes. 2020 Nov 2 doi: 10.1016/j.mayocpiqo.2020.10.005 [Epub ahead of print].[2]Teodoro J. Oscanoa, et al. Frequency of Long QT in Patients with SARS-CoV-2 Infection Treated with Hydroxychloroquine: A Meta-analysis. Int J Antimicrob Agents.[3]Byung Jin Choi, et al. Risk of QT prolongation through Drug-drug Interactions between Hydroxychloroquine and Concomitant Drugs Prescribed in Real-world Practice. Preprint from Research Square, 22 Sep 2020 DOI: 10.21203/rs.3.rs-79572/v1 PPR: PPR217328.Disclosure of Interests:None declare
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