256 research outputs found

    A New Strategy To Identify Rare Blood Donors: Single Polymerase Chain Reaction Multiplex Snapshot Reaction For Detection Of 16 Blood Group Alleles

    Get PDF
    Background. As an alternative to phenotyping, large-scale DNA-based assays, which are feasible for high-throughput donor red blood cell typing, were developed for determination of blood group polymorphisms. However, high-throughput genotyping platforms based on these technologies are still expensive and the inclusion of single nucleotide polymorphisms and analysis of the alleles depend on the manufacturer's determination. To overcome this limitation and in order to develop an assay to enable the screening of rare donors, we developed a SNaPshot assay for analysis of nine single nucleotide polymorphisms related to antigens that are difficult to assess using conventional serology. Materials and methods. The single polymerase chain reaction multiplex SNaPshot reaction was optimized to identify nine single nucleotide polymorphisms determining 16 alleles: KEL*3/KEL*4, KEL*6/KEL*7, DI*1/DI*2, DI*3/DI*4, YT*1/YT*2, CO*1/CO*2, DO*1/DO*2, DO*4, DO*5. We designed a single multiplex PCR with primers encompassing the blood group single nucleotide polymorphisms and performed an internal reaction with probe primers able to discriminate the alleles after fragment analysis. The SNaPshot assay was validated with 140 known alleles previously determined by PCR restriction fragment length polymorphism. Results. We were able to simultaneous detect nine single nucleotide polymorphisms defining 16 blood group alleles on an assay based on a multiplex PCR combined with a single base extension using genomic DNA. Discussion. This study demonstrates a robust genotyping strategy for conducting rare donor screening which can be applied in blood centers and could be an important tool for identifying antigen-negative donors and, therefore, for providing rare blood. © SIMTI Servizi Srl.12SUPPL.1s256s263Jungbauer, C., Routine use of DNA testing for red cell antigens in blood centres (2011) Transfus Apher Sci, 45, pp. 61-68Nance, S.T., How to find, recruit and maintain rare blood donors (2009) Curr Opin Hematol, 16, pp. 503-508Veldhuisen, B., Van Der Schoot, C.E., De Haas, M., Blood group genotyping: From patient to high-throughput donor screening (2009) Vox Sang, 97, pp. 198-206Moulds, J.M., Future of molecular testing for red blood cell antigens (2010) Clin Lab Med, 30, pp. 419-429Patnaik, S.K., Helmberg, W., Blumenfeld, O.O., BGMUT: NCBI dbRBC database of allelic variations of genes encoding antigens of blood group systems (2012) Nucleic Acids Res, 40, pp. D1023-D1029Vallone, P.M., Butler, J.M., AutoDimer: A screening tool for primer-dimer and hairpin structures (2004) Biotechniques, 37, pp. 226-231Baleotti Jr., W., Rios, M., Reid, M.E., Dombrock gene analysis in Brazilian people reveals novel alleles (2006) Vox Sang, 91, pp. 81-87Rios, M., Hue-Roye, K., Oyen, R., Insights into the Holleyand Joseph- phenotypes (2002) Transfusion, 42, pp. 52-58Baleotti Jr., W., Rios, M., Reid, M.E., A novel DI*A allele without the Band 3-Memphis mutation in Amazonian Indians (2003) Vox Sang, 84, pp. 326-330Arnoni, C., Latini, F.R.M., Person, R.M., Padronização das tĂ©cnicas de PCR-RFLP para genotipagem dos alelos KEL*3/ KEL*4 e KEL*5/KEL*6 (2011) Rev Bras Hematol Hemoter, 33 (SUPPL.2), pp. 332-488Baleotti Jr., W., Suzuki, R.B., Ruiz, M., A PCR-RFLP strategy for Wright typing (2011) Rev Bras Hematol Hemoter, 33 (SUPPL. 2), pp. 332-488Brazilian Real - United States Dollar Exchange Rate from Central Bank of Brazil, , http://www4.bcb.gov.br/pec/taxas, April 1st to April 30th, 27/03/2013Daniels, G., The molecular genetics of blood group polymorphism (2009) Hum Genet, 126, pp. 729-742Logdberg, L., Reid, M.E., Zelinski, T., Human blood group genes 2010: Chromosomal locations and cloning strategies revisited (2011) Transfus Med Rev, 25, pp. 36-46Di Cristofaro, J., Silvy, M., Chiaroni, J., Bailly, P., Single PCR multiplex SNaPshot reaction for detection of eleven blood group nucleotide polymorphisms: Optimization, validation, and one year of routine clinical use (2010) J Mol Diagn, 12, pp. 453-460Ferri, G., Pelotti, S., Multiplex ABO genotyping by minisequencing (2009) Methods Mol Biol, 496, pp. 51-58Palacajornsuk, P., Halter, C., Isakova, V., Detection of blood group genes using multiplex SNaPshot method (2009) Transfusion, 49, pp. 740-749Silvy, M., Simon, S., Gouvitsos, J., Weak D and DEL alleles detected by routine SNaPshot genotyping: Identification of four novel RHD alleles (2011) Transfusion, 51, pp. 401-411Silvy, M., Di Cristofaro, J., Beley, S., Identification of RHCE and KEL alleles in large cohorts of Afro-Caribbean and Comorian donors by multiplex SNaPshot and fragment assays: A transfusion support for sickle cell disease patients (2011) Br J Haematol, 154, pp. 260-270Pastinen, T., Kurg, A., Metspalu, A., Minisequencing: A specific tool for DNA analysis and diagnostics on oligonucleotide arrays (1997) Genome Res, 7, pp. 606-614Syvanen, A.C., From gels to chips: "Minisequencing" primer extension for analysis of point mutations and single nucleotide polymorphisms (1999) Hum Mutat, 13, pp. 1-10Information notebook (2011) Blood and Hemoderivates BrasĂ­lia, , MinistĂ©rio da SaĂșde. Secretaria de Atenção Ă  SaĂșde. Coordenação-Geral de Sangue e Hemoderivados. Hemotherapy production. Unified Health System - SUS Brazil - (Public and private contractors). Private non-contracted services by Unified Health System (SUS Brazil). 4th edSantos, N.P., Ribeiro-Rodrigues, E.M., Ribeiro-Dos-Santos, A.K., Assessing individual interethnic admixture and population substructure using a 48-insertion-deletion (INSEL) ancestry-informative marker (AIM) panel (2010) Hum Mutat, 31, pp. 184-190Storry, J.R., Human blood groups: Inheritance and importance in transfusion medicine (2003) J Infus Nurs, 26, pp. 367-37

    Measuring the Spectra of High Energy Neutrinos with a Kilometer-Scale Neutrino Telescope

    Get PDF
    We investigate the potential of a future kilometer-scale neutrino telescope such as the proposed IceCube detector in the South Pole, to measure and disentangle the yet unknown components of the cosmic neutrino flux, the prompt atmospheric neutrinos coming from the decay of charmed particles and the extra-galactic neutrinos, in the 10 TeV to 1 EeV energy range. Assuming a power law type spectra, dÏ•Îœ/dEΜ∌αEÎœÎČd\phi_\nu/dE_\nu \sim \alpha E_\nu^\beta, we quantify the discriminating power of the IceCube detector and discuss how well we can determine magnitude (α\alpha) as well as slope (ÎČ\beta) of these two components of the high energy neutrino spectrum, taking into account the background coming from the conventional atmospheric neutrinos.Comment: 21 pages, 7 figure

    Cosmic Neutrinos and the Energy Budget of Galactic and Extragalactic Cosmic Rays

    Get PDF
    Although kilometer-scale neutrino detectors such as IceCube are discovery instruments, their conceptual design is very much anchored to the observational fact that Nature produces protons and photons with energies in excess of 10^{20} eV and 10^{13} eV, respectively. The puzzle of where and how Nature accelerates the highest energy cosmic particles is unresolved almost a century after their discovery. We will discuss how the cosmic ray connection sets the scale of the anticipated cosmic neutrino fluxes. In this context, we discuss the first results of the completed AMANDA detector and the science reach of its extension, IceCube.Comment: 13 pages, Latex2e, 3 postscript figures included. Talk presented at the International Workshop on Energy Budget in the High Energy Universe, Kashiwa, Japan, February 200

    Gamma-Ray Bursts: The Underlying Model

    Full text link
    A pedagogical derivation is presented of the ``fireball'' model of gamma-ray bursts, according to which the observable effects are due to the dissipation of the kinetic energy of a relativistically expanding wind, a ``fireball.'' The main open questions are emphasized, and key afterglow observations, that provide support for this model, are briefly discussed. The relativistic outflow is, most likely, driven by the accretion of a fraction of a solar mass onto a newly born (few) solar mass black hole. The observed radiation is produced once the plasma has expanded to a scale much larger than that of the underlying ``engine,'' and is therefore largely independent of the details of the progenitor, whose gravitational collapse leads to fireball formation. Several progenitor scenarios, and the prospects for discrimination among them using future observations, are discussed. The production in gamma- ray burst fireballs of high energy protons and neutrinos, and the implications of burst neutrino detection by kilometer-scale telescopes under construction, are briefly discussed.Comment: In "Supernovae and Gamma Ray Bursters", ed. K. W. Weiler, Lecture Notes in Physics, Springer-Verlag (in press); 26 pages, 2 figure

    Cosmic Neutrinos from the Sources of Galactic and Extragalactic Cosmic Rays

    Get PDF
    Although kilometer-scale neutrino detectors such as IceCube are discovery instruments, their conceptual design is very much anchored to the observational fact that Nature produces protons and photons with energies in excess of 10^20 eV and 10^13 eV, respectively. The puzzle of where and how Nature accelerates the highest energy cosmic particles is unresolved almost a century after their discovery. From energetics considerations we anticipate order 10~100 neutrino events per kilometer squared per year pointing back at the source(s) of both galactic and extragalactic cosmic rays. In this context, we discuss the results of the AMANDA and IceCube neutrino telescopes which will deliver a kilometer-square-year of data over the next 3 years.Comment: 8 pages, 4 figure

    Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

    Get PDF
    Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, \nobreak{6×10196\times 10^{19}eV}. The anisotropy was measured by the fraction of arrival directions that are less than 3.1∘3.1^\circ from the position of an active galactic nucleus within 75 Mpc (using the V\'eron-Cetty and V\'eron 12th12^{\rm th} catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38−6+7)(38^{+7}_{-6})%, compared with 2121% expected for isotropic cosmic rays. This is down from the early estimate of (69−13+11)(69^{+11}_{-13})%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.Comment: Accepted for publication in Astroparticle Physics on 31 August 201

    Advanced functionality for radio analysis in the Offline software framework of the Pierre Auger Observatory

    Get PDF
    The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs "radio-hybrid" measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluoresence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request.Comment: accepted for publication in NIM A, 13 pages, minor corrections to author list and references in v

    Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

    Get PDF
    Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

    Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger Observatory

    Get PDF
    We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5×10172.5\times 10^{17} eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L.C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.Comment: 28 pages, 11 figure
    • 

    corecore