ALICE results on vector meson photoproduction in ultra-peripheral p-Pb and Pb-Pb collisions

Lead nuclei, accelerated at the LHC, are sources of strong electromagnetic fields that can be used to measure photon-induced interactions in a new kinematic regime. These interactions can be studied in ultra-peripheral p-Pb and Pb-Pb collisions where impact parameters are larger than the sum of the nuclear radii and hadronic interactions are strongly suppressed. Heavy quarkonium photoproduction is of particular interest since it is sensitive to the gluon distribution in the target. The ALICE Collaboration has studied J/psi and psi(2S) photoproduction in ultra-peripheral Pb-Pb collisions and exclusive J/psi photoproduction off protons in ultra-peripheral p-Pb collisions at the LHC. Implications for the study of gluon density distributions and nuclear gluon shadowing are discussed. Recent ALICE results on rho photoproduction are also presented.Comment: 4 pages, 2 figures, proceedings of the International Conference on Particles and Nuclei (PANIC 2014), Hamburg, Germany, August 25-29, 201

Photoproduction of heavy vector mesons in ultra-peripheral Pb-Pb collisions

Ultra-peripheral Pb-Pb collisions, in which the two nuclei pass close to each other, but at an impact parameter greater than the sum of their radii, provide information about the initial state of nuclei. In particular, heavy vector meson production, where the particle mass sets a hard scale, proceeds in such collisions by photon-gluon interactions, and gives access to nuclear PDFs. The ALICE collaboration has published measurements of J/psi and psi(2S) photoproduction in ultra-peripheral collisions in LHC Run 1 at forward (J/psi) and mid-rapidity, and has obtained a substantially larger data set in 2015 from LHC Run 2, allowing much more detailed studies of the production mechanism to be performed. In particular, the increased energy and more detailed measurements in the forward region in Run 2 give access to significantly lower values of Bjorken-x than in previous studies. In this talk, the latest available results from Run 2 will be given.Comment: 4 pages, 5 figures, XXVIth International Conference on Ultrarelativistic Nucleus-Nucleus Collisions (Quark Matter 2017

Overview of ALICE results

Selected ALICE results on the global event properties, particle spectra, azimuthal anisotropy, heavy flavour and quarkonium production in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV are presented. First results on p-Pb collisions at sqrt(s_NN) = 5.02 TeV are briefly reviewed.Comment: 5 pages, proceedings of the conference "New Trends in High Energy Physics", Alushta, Ukraine, September 23-29, 201

Anti-inflammatory and immunomodulating effects of the bacterial lysate in the <em>in vivo</em> models of aseptic lymphadenitis and pneumococcal pneumonia

Bacterial lysates may produce immunoregulatory effects in the inflammatory diseases that are not directly caused by infectious agents; they may also stimulate the immune response against pathogens which are not a part of the lysate composition. Imudon® is a polyvalent bacterial lysate that is available in orodispersible tablets. However, the influence of this drug product on aseptic inflammation and immune defense against the infectious agents, the antigens of which are not contained in this preparation have not been studied so far. The aim of this study, therefore, was to determine the anti-inflammatory and immunomodulating effects of Imudon® using the models of aseptic lymphadenitis (in Wistar rats) and pneumococcal pneumonia (in Balb/c mice), i.e., the conditions not related to the specific components of the bacterial lysate. Lymphadenitis was induced in rats by administration of λ-carrageenan into a cervical lymph node via an open operative approach. Whereas pneumonia was induced in mice by administering Streptococcus pneumoniae suspension intranasally. The choice of pneumococcus was determined by the absence of pneumococcal antigens in Imudon®, i.e., it cannot be a direct inducer of adaptive immune response against pneumococcal infection. Imudon® was administered intragastrically as a crushed tablet suspension following a therapeutic-preventive regimen (for 14 days daily until the induction of inflammation and for 3 [in the lymphadenitis model] or 5 days [in the model of pneumonia] in three doses thereafter). In the lymphadenitis model, Imudon® demonstrated both local and systemic anti-inflammatory responses manifested in the reduced number of circulating leucocytes and lower TNFα levels and by ameliorated histological features of inflammation in the operated lymph node. In rats, the anti-inflammatory effect was most pronounced when the product was administered at a dose of 2.2 mg/kg (equivalent to a human therapeutic dose) and 6.6 mg/kg. In the model of pneumonia, administration of Imudon® at 4.44 mg/kg (equivalent to a human therapeutic dose) and 13.32 mg/kg demonstrated a trend towards increased survival rate as compared to the control group. On Day 5 after infection Imudon® (4.44 and 13.32 mg/kg) decreased significantly the severity of inflammation and bacterial titer in the lungs. The titer of anti-pneumococcal immunoglobulins A in the bronchoalveolar lavage fluid were found to be higher in the Imudon® treated group (13.32 mg/kg) compared to control group. The results of this study showed high antiinflammatory and immunomodulatory activities of Imudon® and provided an insight into the mechanisms that underlie the clinical effects of this drug in various inflammatory diseases