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
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
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,
, we quantify the discriminating
power of the IceCube detector and discuss how well we can determine magnitude
() as well as slope () 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
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
Analysis of the genetic polymorphism of Paracoccidioides brasiliensis and Paracoccidioides cerebriformis "Moore" by random amplified polymorphic DNA (RAPD) and 28S ribosomal DNA sequencing: Paracoccidioides cerebriformis revisited
Gamma-Ray Bursts: The Underlying Model
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
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
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{eV}. The
anisotropy was measured by the fraction of arrival directions that are less
than from the position of an active galactic nucleus within 75 Mpc
(using the V\'eron-Cetty and V\'eron 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 , compared
with expected for isotropic cosmic rays. This is down from the early
estimate of . 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
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
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
We present the results of searches for dipolar-type anisotropies in different
energy ranges above 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% 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
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