109 research outputs found
Expanding the knowledge about Leishmania species in wild mammals and dogs in the Brazilian savannah
Background: Wild, synanthropic and domestic mammals act as hosts and/or reservoirs of several Leishmania spp. Studies on possible reservoirs of Leishmania in different areas are fundamental to understand host-parasite interactions and develop strategies for the surveillance and control of leishmaniasis. In the present study, we evaluated the Leishmania spp. occurrence in mammals in two conservation units and their surroundings in Brasília, Federal District (FD), Brazil. Methods: Small mammals were captured in Brasília National Park (BNP) and Contagem Biological Reserve (CBR) and
dogs were sampled in residential areas in their vicinity. Skin and blood samples were evaluated by PCR using different molecular markers (D7 24Sα rRNA and rDNA ITS1). Leishmania species were identified by sequencing of PCR products. Dog blood samples were subjected to the rapid immunochromatographic test (DPP) for detection of anti-Leishmania infantum antibodies. Results: 179 wild mammals were studied and 20.1% had Leishmania DNA successfully detected in at least one sample. Six mammal species were considered infected: Clyomys laticeps, Necromys lasiurus, Nectomys rattus, Rhipidomys macrurus, Didelphis albiventris and Gracilinanus agilis. No significant difference, comparing the proportion of individuals with Leishmania spp., was observed between the sampled areas and wild mammal species. Most of the positive samples were collected from the rodent N. lasiurus, infected by L. amazonensis or L. braziliensis. Moreover, infections by Trypanosoma spp. were detected in N. lasiurus and G. agilis. All 19 dog samples were positive by DPP; however, only three (15.8%) were confirmed by PCR assays. DNA sequences of ITS1 dog amplicons showed 100% identity with L. infantum sequence. Conclusions: The results suggest the participation of six species of wild mammals in the enzootic transmission of Leishmania spp. in FD. This is the first report of L. amazonensis in N. lasiurus
Out of Their Depth? Isolated Deep Populations of the Cosmopolitan Coral Desmophyllum dianthus May Be Highly Vulnerable to Environmental Change
Deep sea scleractinian corals will be particularly vulnerable to the effects of
climate change, facing loss of up to 70% of their habitat as the
Aragonite Saturation Horizon (below which corals are unable to form calcium
carbonate skeletons) rises. Persistence of deep sea scleractinian corals will
therefore rely on the ability of larvae to disperse to, and colonise, suitable
shallow-water habitat. We used DNA sequence data of the internal transcribed
spacer (ITS), the mitochondrial ribosomal subunit (16S) and mitochondrial
control region (MtC) to determine levels of gene flow both within and among
populations of the deep sea coral Desmophyllum dianthus in SE
Australia, New Zealand and Chile to assess the ability of corals to disperse
into different regions and habitats. We found significant genetic subdivision
among the three widely separated geographic regions consistent with isolation
and limited contemporary gene flow. Furthermore, corals from different depth
strata (shallow <600 m, mid 1000–1500 m, deep >1500 m) even on the
same or nearby seamounts were strongly differentiated, indicating limited
vertical larval dispersal. Genetic differentiation with depth is consistent with
the stratification of the Subantarctic Mode Water, Antarctic Intermediate Water,
the Circumpolar Deep and North Pacific Deep Waters in the Southern Ocean, and we
propose that coral larvae will be retained within, and rarely migrate among,
these water masses. The apparent absence of vertical larval dispersal suggests
deep populations of D. dianthus are unlikely to colonise
shallow water as the aragonite saturation horizon rises and deep waters become
uninhabitable. Similarly, assumptions that deep populations will act as refuges
for shallow populations that are impacted by activities such as fishing or
mining are also unlikely to hold true. Clearly future environmental management
strategies must consider both regional and depth-related isolation of deep-sea
coral populations
Effects of resuscitation with crystalloid fluids on cardiac function in patients with severe sepsis
<p>Abstract</p> <p>Background</p> <p>The use of hypertonic crystalloid solutions, including sodium chloride and bicarbonate, for treating severe sepsis has been much debated in previous investigations. We have investigated the effects of three crystalloid solutions on fluid resuscitation in severe sepsis patients with hypotension.</p> <p>Methods</p> <p>Ninety-four severe sepsis patients with hypotension were randomly assigned to three groups. The patients received the following injections within 15 min at initial treatment: Ns group (n = 32), 5 ml/kg normal saline; Hs group (n = 30), with 5 ml/kg 3.5% sodium chloride; and Sb group (n = 32), 5 ml/kg 5% sodium bicarbonate. Cardiac output (CO), systolic blood pressure, mean arterial pressure (MAP), body temperature, heart rate, respiratory rate and blood gases were measured.</p> <p>Results</p> <p>There were no differences among the three groups in CO, MAP, heart rate or respiratory rate during the 120 min trial or the 8 hour follow-up, and no significant differences in observed mortality rate after 28 days. However, improvement of MAP and CO started earlier in the Sb group than in the Ns and Hs groups. Sodium bicarbonate increased the base excess but did not alter blood pH, lactic acid or [HCO<sub>3</sub>]<sup>- </sup>values; and neither 3.5% hypertonic saline nor 5% sodium bicarbonate altered the Na<sup>+</sup>, K<sup>+</sup>, Ca<sup>2+ </sup>or Cl<sup>- </sup>levels.</p> <p>Conclusion</p> <p>All three crystalloid solutions may be used for initial volume loading in severe sepsis, and sodium bicarbonate confers a limited benefit on humans with severe sepsis.</p> <p>Trial registration</p> <p>ISRCTN36748319.</p
Desmophyllum dianthus (Esper, 1794) in the scleractinian phylogeny and its intraspecific diversity
© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 7 (2012): e50215, doi:10.1371/journal.pone.0050215.The cosmopolitan solitary deep-water scleractinian coral Desmophyllum dianthus (Esper, 1794) was selected as a representative model species of the polyphyletic Caryophylliidae family to (1) examine phylogenetic relationships with respect to the principal Scleractinia taxa, (2) check population structure, (3) test the widespread connectivity hypothesis and (4) assess the utility of different nuclear and mitochondrial markers currently in use. To carry out these goals, DNA sequence data from nuclear (ITS and 28S) and mitochondrial (16S and COI) markers were analyzed for several coral species and for Mediterranean populations of D. dianthus. Three phylogenetic methodologies (ML, MP and BI), based on data from the four molecular markers, all supported D. dianthus as clearly belonging to the “robust” clade, in which the species Lophelia pertusa and D. dianthus not only grouped together, but also shared haplotypes for some DNA markers. Molecular results also showed shared haplotypes among D. dianthus populations distributed in regions separated by several thousands of kilometers and by clear geographic barriers. These results could reflect limited molecular and morphological taxonomic resolution rather than real widespread connectivity. Additional studies are needed in order to find molecular markers and morphological features able to disentangle the complex phylogenetic relationship in the Order Scleractinia and to differentiate isolated populations, thus avoiding the homoplasy found in some morphological characters that are still considered in the literature.This study was funded by CTM2009-00496 and CGL2011-23306 projects of the “Ministerio de Ciencia e Innovación” (Spain). Research at sea was partly supported by the European Commission F. P.VI Project HERMES Contract No. GOCE-CT-2005-511234-1) and the EU F.P. VII Project HERMIONE(contract number no. 226354)
Dark Energy Survey Year 3 Results: Cosmology from Cosmic Shear and Robustness to Modeling Uncertainty
This work and its companion paper, Amon et al. [Phys. Rev. D 105, 023514 (2022)], present cosmic shear measurements and cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrain the lensing amplitude parameter
S
8
≡
σ
8
√
Ω
m
/
0.3
at the 3% level in
Λ
CDM
:
S
8
=
0.75
9
+
0.025
−
0.023
(68% CL). Our constraint is at the 2% level when using angular scale cuts that are optimized for the
Λ
CDM
analysis:
S
8
=
0.77
2
+
0.018
−
0.017
(68% CL). With cosmic shear alone, we find no statistically significant constraint on the dark energy equation-of-state parameter at our present statistical power. We carry out our analysis blind, and compare our measurement with constraints from two other contemporary weak lensing experiments: the Kilo-Degree Survey (KiDS) and Hyper-Suprime Camera Subaru Strategic Program (HSC). We additionally quantify the agreement between our data and external constraints from the Cosmic Microwave Background (CMB). Our DES Y3 result under the assumption of
Λ
CDM
is found to be in statistical agreement with Planck 2018, although favors a lower
S
8
than the CMB-inferred value by
2.3
σ
(a
p
-value of 0.02). This paper explores the robustness of these cosmic shear results to modeling of intrinsic alignments, the matter power spectrum and baryonic physics. We additionally explore the statistical preference of our data for intrinsic alignment models of different complexity. The fiducial cosmic shear model is tested using synthetic data, and we report no biases greater than
0.3
σ
in the plane of
S
8
×
Ω
m
caused by uncertainties in the theoretical models
The CHEK2 Variant C.349A>G Is Associated with Prostate Cancer Risk and Carriers Share a Common Ancestor
Simple SummaryIt is well-recognised the strong contribution of genetic factors to prostate cancer (PrCa) susceptibility, thus genetic screening is critical for presymptomatic diagnosis and identification of individuals at high-risk. In this context, recurrent founder variants in cancer predisposing genes, by providing specific targets for early identification of carriers at risk of developing the disease, may be leveraged to implement cost-efficient targeted genetic screening strategies. The goal of this study was to investigate whether CHEK2 c.349A>G, the only recurrent "likely pathogenic" variant in CHEK2 gene reported in the Portuguese population, plays an important role in PrCa development, and the possibility of a founder effect behind its origin. Our results clearly demonstrate that c.349A>G in the CHEK2 tumour-suppressor gene is a founder variant significantly associated with an increased risk of PrCa, suggesting its potential usefulness for cost-effective targeted genetic screening in PrCa families.The identification of recurrent founder variants in cancer predisposing genes may have important implications for implementing cost-effective targeted genetic screening strategies. In this study, we evaluated the prevalence and relative risk of the CHEK2 recurrent variant c.349A>G in a series of 462 Portuguese patients with early-onset and/or familial/hereditary prostate cancer (PrCa), as well as in the large multicentre PRACTICAL case-control study comprising 55,162 prostate cancer cases and 36,147 controls. Additionally, we investigated the potential shared ancestry of the carriers by performing identity-by-descent, haplotype and age estimation analyses using high-density SNP data from 70 variant carriers belonging to 11 different populations included in the PRACTICAL consortium. The CHEK2 missense variant c.349A>G was found significantly associated with an increased risk for PrCa (OR 1.9; 95% CI: 1.1-3.2). A shared haplotype flanking the variant in all carriers was identified, strongly suggesting a common founder of European origin. Additionally, using two independent statistical algorithms, implemented by DMLE+2.3 and ESTIAGE, we were able to estimate the age of the variant between 2300 and 3125 years. By extending the haplotype analysis to 14 additional carrier families, a shared core haplotype was revealed among all carriers matching the conserved region previously identified in the high-density SNP analysis. These findings are consistent with CHEK2 c.349A>G being a founder variant associated with increased PrCa risk, suggesting its potential usefulness for cost-effective targeted genetic screening in PrCa families
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Measurements of the Higgs boson production cross section and couplings in the W boson pair decay channel in proton-proton collisions at = 13 TeV
A preprint version of the article is available at arXiv:2206.09466v2 [hep-ex], https://arxiv.org/abs/2206.09466v2 . Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at httpS://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-20-013 (CMS Public Pages). Report number: CMS-HIG-20-013, CERN-EP-2022-120.Production cross sections of the standard model Higgs boson decaying to a pair of W bosons are measured in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis targets Higgs bosons produced via gluon fusion, vector boson fusion, and in association with a W or Z boson. Candidate events are required to have at least two charged leptons and moderate missing transverse momentum, targeting events with at least one leptonically decaying W boson originating from the Higgs boson. Results are presented in the form of inclusive and differential cross sections in the simplified template cross section framework, as well as couplings of the Higgs boson to vector bosons and fermions. The data set collected by the CMS detector during 2016-2018 is used, corresponding to an integrated luminosity of 138 fb^−1. The signal strength modifier μ, defined as the ratio of the observed production rate in a given decay channel to the standard model expectation, is measured to be μ = 0.95 +0.10−0.09. All results are found to be compatible with the standard model within the uncertainties.SCOAP3
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Measurement of inclusive and differential cross sections for single top quark production in association with a W boson in proton-proton collisions at = 13 TeV
A preprint version of the article is available at arXiv:2208.00924v2 [hep-ex], https://arxiv.org/abs/2208.00924v2 . Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables, including additional supplementary figures, can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/TOP-21-010 (CMS Public Pages). Report number: CMS-TOP-21-010, CERN-EP-2022-158.Measurements of the inclusive and normalised differential cross sections are presented for the production of single top quarks in association with a W boson in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data used were recorded with the CMS detector at the LHC during 2016-2018, and correspond to an integrated luminosity of 138 fb^{−1}. Events containing one electron and one muon in the final state are analysed. For the inclusive measurement, a multivariate discriminant, exploiting the kinematic properties of the events is used to separate the signal from the dominant tt¯ background. A cross section of 79.2 ± 0.9 (stat) +7.7−8.0 (syst) ± 1.2 (lumi) pb is obtained, consistent with the predictions of the standard model. For the differential measurements, a fiducial region is defined according to the detector acceptance, and the requirement of exactly one jet coming from the fragmentation of a bottom quark. The resulting distributions are unfolded to particle level and agree with the predictions at next-to-leading order in perturbative quantum chromodynamics.SCOAP3
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Search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state in proton-proton collisions at = 13 TeV
A preprint version of this article is available at arXiv:2210.00043v2 [hep-ex], https://arxiv.org/abs/2210.00043v2 . Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables, including additional supplementary figures, can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/B2G-20-009 (CMS Public Pages). Report number: CMS-B2G-20-009, CERN-EP-2022-152.Data availability: see: https://cms-results.web.cern.ch/cms-results/public-results/publications/B2G-20-009 .A search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state is presented. The analysis is based on proton-proton collision data recorded by the CMS detector in 2016-2018 at a centre-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 138 fb^{-1}. The search is sensitive to resonances with masses between 1.3 and 6 TeV, decaying to bosons that are highly Lorentz-boosted such that each of the bosons forms a single large-radius jet. Machine learning techniques are employed to identify such jets. No significant excess over the estimated standard model background is observed. A maximum local significance of 3.6 standard deviations, corresponding to a global significance of 2.3 standard deviations, is observed at masses of 2.1 and 2.9 TeV. In a heavy vector triplet model, spin-1 Z' and W' resonances with masses below 4.8 TeV are excluded at the 95% confidence level (CL). These limits are the most stringent to date. In a bulk graviton model, spin-2 gravitons and spin-0 radions with masses below 1.4 and 2.7 TeV, respectively, are excluded at 95% CL. Production of heavy resonances through vector boson fusion is constrained with upper cross section limits at 95% CL as low as 0.1 fb.SCOAP3
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