Brazilian Plasmodium falciparum isolates: investigation of candidate polymorphisms for artemisinin resistance before introduction of artemisinin-based combination therapy

<p>Abstract</p> <p>Background</p> <p>This study was performed to better understand the genetic diversity of known polymorphisms in <it>pfatpase6 </it>and <it>pfmdr1 </it>genes before the introduction of ACT in Brazil, in order to get a genotypic snapshot of <it>Plasmodium falciparum </it>parasites that may be used as baseline reference for future studies.</p> <p>Methods</p> <p>Parasites from <it>P. falciparum </it>samples collected in 2002, 2004 and 2006-2007 were genotyped using PCR and DNA sequencing at codons 86, 130, 184, 1034, 1042, 1109 and 1246 for <it>pfmdr1 </it>gene, and 243, 263, 402, 431, 623, 630, 639, 683, 716, 776, 769 and 771 for <it>pfatpase6 </it>gene.</p> <p>Results</p> <p>A <it>pfmdr1 </it>haplotype NEF/CDVY was found in 97% of the samples. In the case of <it>pfatpase6</it>, four haplotypes, wild-type (37%), 630 S (35%), 402 V (5%) and double-mutant 630 S + 402 V (23%), were detected.</p> <p>Conclusion</p> <p>Although some polymorphism in <it>pfmdr1 </it>and <it>pfatpase6 </it>were verified, no reported haplotypes in both genes that may mediate altered response to ACT was detected before the introduction of this therapy in Brazil. Thus, the haplotypes herein described can be very useful as a baseline reference of <it>P. falciparum </it>populations without ACT drug pressure.</p

Meiotic chromosomes and nucleolar behavior in testicular cells of the grassland spittlebugs Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana (Hemiptera, Auchenorrhyncha)

Spittlebugs annually infest pastures and cause severe damage, representing a serious problem for the tropical American beef cattle industry. Spittlebugs are an important biotic constraint to forage production and there is a lack of cytogenetic data for this group of insects. For these reasons, we conducted this work, in which the spermatogenesis and nucleolar behavior of Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana were studied. The males possessed testes in the shape of a “bunch of grapes”; a variable number of testicular lobes per individual and polyploid nuclei composed of several heteropycnotic bodies. A heteropycnotic area was located in the periphery of the nucleus (prophase I); the chiasmata were terminal or interstitial; metaphases I were circular or linear and anaphase showed late migration of the sex chromosome. The chromosome complement had 2n = 19, except for N. entreriana (2n = 15); the spermatids were round with heteropycnotic material in the center and elongated with conspicuos chromatin. The analysis of testes after silver nitrate staining showed polyploid nuclei with three large and three smaller nucleolar bodies. Early prophase cells had an intensely stained nucleolar body located close to the chromatin and another less evident body located away from the chromatin. The nucleolar bodies disintegrated during diplotene. Silver staining occurred in two autosomes, in terminal and subterminal locations, the latter probably corresponding to the nucleolus organizer regions (NORs). The spermatids were round with a round nucleolar body and silver staining was observed in the medial and posterior region of the elongated part of the spermatid head

Immunodominant Antigens of Leishmania chagasi Associated with Protection against Human Visceral Leishmaniasis

One of the most striking features of infection by Leishmania chagasi is that infection leads to a spectrum of clinical outcomes ranging from asymptomatic infection to active disease. The existence of asymptomatic infected people has served as an incentive to believe that an effective vaccine is possible, but unfortunately no successful immunological characterization of such cases was obtained. Patients recovered from visceral leishmaniasis show a similar immunological profile to asymptomatic infected individuals and both exhibit a strong cell-mediated immune response against Leishmania antigens and are resistant to disease. Since the past decade several approaches were undertaken to try to shed light on the immunological profile associated with such “resistance” to infections, notwithstanding antigenic recognition profile associated to resistance to infection was not successfully explored. In the present manuscript we describe a specific IgG recognizing pattern associated with resistant individuals (asymptomatic infected people and recovery patients to visceral leishmaniasis). These data highlight the possibility of using specific proteins in serological tests for the identification of asymptomatic infected individuals

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

The azimuthal anisotropy of charged particles in PbPb collisions at nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pt) range up to approximately 60 GeV. The data cover both the low-pt region associated with hydrodynamic flow phenomena and the high-pt region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with pt, reaching a maximum around pt = 3 GeV, and then to gradually decrease to almost zero, with the decline persisting up to at least pt = 40 GeV over the full centrality range measured.Comment: Replaced with published version. Added journal reference and DO

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy

A search for new physics is performed in events with two same-sign isolated leptons, hadronic jets, and missing transverse energy in the final state. The analysis is based on a data sample corresponding to an integrated luminosity of 4.98 inverse femtobarns produced in pp collisions at a center-of-mass energy of 7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of 140 increase in integrated luminosity over previously published results. The observed yields agree with the standard model predictions and thus no evidence for new physics is found. The observations are used to set upper limits on possible new physics contributions and to constrain supersymmetric models. To facilitate the interpretation of the data in a broader range of new physics scenarios, information on the event selection, detector response, and efficiencies is provided.Comment: Published in Physical Review Letter

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Compressed representation of a partially defined integer function over multiple arguments

In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one