9 research outputs found

    Intravesical Ty21a vaccine promotes dendritic cells and T cell-mediated tumor regression in the MB49 bladder cancer model

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    Preclinical data shows that intravesical instillation of Ty21a/Vivotif\uae, a commercial vaccine against typhoid fever, is an effective alternative option to standard Bacillus-Calmette-Gu\ue9rin (BCG) immunotherapy for nonmuscle-invasive bladder cancer (NMIBC). Here we characterized the inflammatory effects of Ty21a on the bladder and investigated the immune mechanisms underlying tumor-regression towards the use of this bacterial vaccine in NMIBC patients. MB49 bladder tumor-bearing mice had significantly improved survival after intravesical instillations of Ty21a doses of 106 to 108 colony-forming units. By immunohistochemistry and morphology, both BCG and Ty21a instillations were associated with bladder inflammation, which was decreased with the use of low, but effective, doses of Ty21a. Flow cytometry analysis showed a significant infiltration of T cells, natural killer (NK) cells, and myeloid cells, compared with controls, after a single dose of Ty21a, whereas this was only observed after multiple doses of BCG. The induced myeloid cells were predominantly neutrophils and Ly6C+CD103+ dendritic cells (DC), the latter being significantly more numerous after instillation of Ty21a than BCG. Ex vivo infection of human leukocytes with Ty21a, but not BCG, similarly significantly increased DC frequency. CD4+ and CD8+ T cells, but not NK cells nor neutrophils, were required for effective Ty21a bladder tumor responses. Thus, the generation of antitumor adaptive immunity was identified as a key process underlying Ty21a-mediated treatment efficacy. Altogether, these results demonstrate mechanisms of intravesical Ty21a therapy and suggest its potential as a safe and effective treatment for NMIBC patients

    Precise tests of low energy QCD from Ke4 decay properties

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    We report results from the analysis of the K\ub1 \u2192 pi+ pi 12 e\ub1 \u3bd (Ke4 ) decay by the NA48/2 collaboration at the CERN SPS, based on the total statistics of 1.13 million decays collected in 2003\u20132004. The hadronic form factors in the S- and P-wave and their variation with energy are obtained. The phase difference between the S- and P-wave states of the pion pion system is accurately measured and allows a precise determination of a00 and a02 , the I = 0 and I = 2 S-wave pion pion scattering lengths: a00 = 0.2220 \ub1 0.0128stat \ub1 0.0050syst \ub1 0.0037th , a02 = 120.0432 \ub1 0.0086stat \ub1 0.0034syst \ub1 0.0028th . Combination of this result with the other NA48/2 measurement obtained in the study of K\ub1 \u2192 pi0 pi0 pi\ub1 decays brings an improved determination of a00 and the first precise experimental measurement of a02, providing a stringent test ofChiral Perturbation Theory predictions and lattice QCD calculations. Using constraints based on analyticity and chiral symmetry, even more precise values are obtained: a00 = 0.2196 \ub1 0.0028stat \ub1 0.0020syst and a02 = 120.0444 \ub10.0007stat \ub1 0.0005syst \ub1 0.0008ChPT

    Search for the dark photon in pi0 decays

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    Abstract A sample of 1.69 7 10 7 fully reconstructed \u3c0 0 \u2192 \u3b3 e + e 12 decay candidates collected by the NA48/2 experiment at \{CERN\} in 2003\u20132004 is analyzed to search for the dark photon ( A \u2032 ) production in the \u3c0 0 \u2192 \u3b3 A \u2032 decay followed by the prompt A \u2032 \u2192 e + e 12 decay. No signal is observed, and an exclusion region in the plane of the dark photon mass m A \u2032 and mixing parameter \u3b5 2 is established. The obtained upper limits on \u3b5 2 are more stringent than the previous limits in the mass range 9 \ua0 MeV / c 2 < m A \u2032 < 70 \ua0 MeV / c 2 . The NA48/2 sensitivity to the dark photon production in the K \ub1 \u2192 \u3c0 \ub1 A \u2032 decay is also evaluated

    Searches for lepton number violation and resonances in K+- -> pi mu mu decays

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    The NA48/2 experiment at CERN collected a large sample of charged kaon decays to final states with multiple charged particles in 2003\ue2\u80\u932004. A new upper limit on the rate of the lepton number violating decay K\uc2\ub1\ue2\u86\u92\ucf\u80\ue2\u88\u93\uce\ubc\uc2\ub1\uce\ubc\uc2\ub1is reported: B(K\uc2\ub1\ue2\u86\u92\ucf\u80\ue2\u88\u93\uce\ubc\uc2\ub1\uce\ubc\uc2\ub1)<8.6\uc3\u9710\ue2\u88\u9211at 90% CL. Searches for two-body resonances X in K\uc2\ub1\ue2\u86\u92\ucf\u80\uce\ubc\uce\ubc decays (such as heavy neutral leptons N4and inflatons \ucf\u87) are also presented. In the absence of signals, upper limits are set on the products of branching fractions B(K\uc2\ub1\ue2\u86\u92\uce\ubc\uc2\ub1N4)B(N4\ue2\u86\u92\ucf\u80\uce\ubc) and B(K\uc2\ub1\ue2\u86\u92\ucf\u80\uc2\ub1X)B(X\ue2\u86\u92\uce\ubc+\uce\ubc\ue2\u88\u92) for ranges of assumed resonance masses and lifetimes. The limits are in the (10\ue2\u88\u9211,10\ue2\u88\u929) range for resonance lifetimes below 100 ps

    Measurements of charged kaon semileptonic decay branching fractions K-+/- -> pi(0)mu(+/-)v and K-+/- -> pi(0)e(+/-)v and their ratio (vol 50, pg 329, 2007) RID A-4071-2012

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    In an earlier paper [1], the background for K-e3 was over estimated due to an erroneous calculation of the electron identification efficiency. The correct ratios of the partial widths involving this channel are R-Ke3/K2 pi = 0.2470 +/- 0.0009 (stat) +/- 0.0004 (syst) and R-K mu 3/Ke3 = 0.663 +/- 0.003 (stat) +/- 0.001 (syst). Assuming the PDG value [2] for the K-2 pi branching ratio, the measured branching fraction of Br (K-e3) continues to exceed the current PDG value [2]. The extracted value of |V-us|f(+)(0) is in agreement with the CKM unitary prediction; thus, our conclusions in [1] do not change

    Detailed study of the K\ub1 \u2192 \u3c0 0\u3c00e\ub1\u3bd (Ke4 00) decay properties

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    A sample of 65210 K\ub1 \u2192 \u3c00\u3c00e\ub1\u3bd (Ke4 00) decay candidates with 1% background contamination has been collected in 2003-2004 by the NA48/2 collaboration at the CERN SPS. A study of the differential rate provides the first measurement of the hadronic form factor variation in the plane (M\u3c0\u3c0 2, Me\u3bd 2) and brings evidence for a cusp-like structure in the distribution of the squared \u3c00\u3c00 invariant mass around (Formula Presented). Exploiting a model independent description of this form factor, the branching ratio, inclusive of radiative decays, is obtained using the K\ub1 \u2192 \u3c00\u3c00\u3c0\ub1 decay mode as normalization. It is measured to be BR(Ke4 00) = (2.552 \ub1 0.010stat \ub1 0.010syst \ub1 0.032ext) 7 10 125, which improves the current world average precision by an order of magnitude while the 1.4% relative precision is dominated by the external uncertainty from the normalization mode. A comparison with the properties of the corresponding mode involving a \u3c0+\u3c0 12 pair (Ke4 + 12) is also presented

    High precision measurement of the form factors of the semileptonic decays K\ub1 \u2192 \u3c00l\ub1\u3bd (Kl3) in NA48/2

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    The data collected by NA48/2 in 2003-2004 allowed several precise measurements in the charged kaon decay sector. In this paper we present the results obtained using a sample of 2.5 7106 K\ub1 \u2192 \u3c00\u3bc\ub1\u3bd (K\u3bc3) and 4.0 7106 K 7 \u2192 \u3c00l \ub1\u3bd (Ke3) events, collected in 2004 using a minimal trigger configuration. This unbiassed sample of kaon decays allows a high precision measurement of the semileptonic form factors. \ua9 Copyright owned by the author(s)

    A new measurement of the K \ub1 \u2192 \u3c0 \ub1\u3b3\u3b3 decay at the NA48/2 experiment

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    The NA48/2 experiment at CERN collected two data samples with minimum bias trigger conditions in 2003 and 2004. A measurement of the rate and dynamic properties of the rare decay K \ub1 \u2192 \u3c0 \ub1\u3b3\u3b3 from these data sets based on 149 decay candidates with an estimated background of 15.5 \ub1 0.7 events is reported. The model-independent branching ratio in the kinematic range z=(m\u3b3\u3b3/mK)2&gt;0.2 is measured to be BMI(z&gt;0.2)=(0.877\ub10.089) 710-6, and the branching ratio in the full kinematic range assuming a particular Chiral Perturbation Theory description to be B(K\u3c0\u3b3\u3b3)=(0.910\ub10.075) 710-6. \ua9 2014 The Authors

    Searches for lepton number violation and resonances in K\ub1\ua0\u2192\ua0\u3c0\u3bc\u3bc decays

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    The NA48/2 experiment at CERN collected a large sample of charged kaon decays to final states with multiple charged particles in 2003\u20132004. A new upper limit on the rate of the lepton number violating decay K\ub1\u2192\u3c0 13\u3bc\ub1\u3bc\ub1 is reported: B(K\ub1\u2192\u3c0 13\u3bc\ub1\u3bc\ub1)<8.6 710 1211 at 90% CL. Searches for two-body resonances X in K\ub1\u2192\u3c0\u3bc\u3bc decays (such as heavy neutral leptons N4 and inflatons \u3c7) are also presented. In the absence of signals, upper limits are set on the products of branching fractions B(K\ub1\u2192\u3bc\ub1N4)B(N4\u2192\u3c0\u3bc) and B(K\ub1\u2192\u3c0\ub1X)B(X\u2192\u3bc+\u3bc 12) for ranges of assumed resonance masses and lifetimes. The limits are in the (10 1211,10 129) range for resonance lifetimes below 100 ps. \ua9 2017 The Author(s
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