2,382 research outputs found
Dynamic expression of Ralstonia solanacearum virulence factors and metabolism-controlling genes during plant infection
Altres ajuts: CERCA Programme/Generalitat de Catalunya. P. Sebastià received the support of a fellowship (code is LCF/BQ/IN17/11620004) from la Caixa Foundation (identifier [ID] 100010434)Background: Ralstonia solanacearum is the causal agent of bacterial wilt, a devastating plant disease responsible for serious economic losses especially on potato, tomato, and other solanaceous plant species in temperate countries. In R. solanacearum, gene expression analysis has been key to unravel many virulence determinants as well as their regulatory networks. However, most of these assays have been performed using either bacteria grown in minimal medium or in planta, after symptom onset, which occurs at late stages of colonization. Thus, little is known about the genetic program that coordinates virulence gene expression and metabolic adaptation along the different stages of plant infection by R. solanacearum. Results: We performed an RNA-sequencing analysis of the transcriptome of bacteria recovered from potato apoplast and from the xylem of asymptomatic or wilted potato plants, which correspond to three different conditions (Apoplast, Early and Late xylem). Our results show dynamic expression of metabolism-controlling genes and virulence factors during parasitic growth inside the plant. Flagellar motility genes were especially up-regulated in the apoplast and twitching motility genes showed a more sustained expression in planta regardless of the condition. Xylem-induced genes included virulence genes, such as the type III secretion system (T3SS) and most of its related effectors and nitrogen utilisation genes. The upstream regulators of the T3SS were exclusively up-regulated in the apoplast, preceding the induction of their downstream targets. Finally, a large subset of genes involved in central metabolism was exclusively down-regulated in the xylem at late infection stages. Conclusions: This is the first report describing R. solanacearum dynamic transcriptional changes within the plant during infection. Our data define four main genetic programmes that define gene pathogen physiology during plant colonisation. The described expression of virulence genes, which might reflect bacterial states in different infection stages, provides key information on the R. solanacearum potato infection process
Mutations related to Antiretroviral Resistance identified by ultra-deep sequencing in HIV-1 infected children under Structured Interruptions of HAART
Altres ajuts: CONACYT/GCPS/44519Although Structured Treatment Interruptions (STI) are currently not considered an alternative strategy for antiretroviral treatment, their true benefits and limitations have not been fully established. Some studies suggest the possibility of improving the quality of life of patients with this strategy; however, the information that has been obtained corresponds mostly to studies conducted in adults, with a lack of knowledge about its impact on children. Furthermore, mutations associated with antiretroviral resistance could be selected due to sub-therapeutic levels of HAART at each interruption period. Genotyping methods to determine the resistance profiles of the infecting viruses have become increasingly important for the management of patients under STI, thus low-abundance antiretroviral drug-resistant mutations (DRM's) at levels under limit of detection of conventional genotyping (<20% of quasispecies) could increase the risk of virologic failure. In this work, we analyzed the protease and reverse transcriptase regions of the pol gene by ultra-deep sequencing in pediatric patients under STI with the aim of determining the presence of high- and low-abundance DRM's in the viral rebounds generated by the STI. High-abundance mutations in protease and high- and low-abundance mutations in reverse transcriptase were detected but no one of these are directly associated with resistance to antiretroviral drugs. The results could suggest that the evaluated STI program is virologically safe, but strict and carefully planned studies, with greater numbers of patients and interruption/restart cycles, are still needed to evaluate the selection of DRM's during STI
AEGIS: Demographics of X-ray and Optically Selected AGNs
We develop a new diagnostic method to classify galaxies into AGN hosts,
star-forming galaxies, and absorption-dominated galaxies by combining the [O
III]/Hbeta ratio with rest-frame U-B color. This can be used to robustly select
AGNs in galaxy samples at intermediate redshifts (z<1). We compare the result
of this optical AGN selection with X-ray selection using a sample of 3150
galaxies with 0.3<z<0.8 and I_AB<22, selected from the DEEP2 Galaxy Redshift
Survey and the All-wavelength Extended Groth Strip International Survey
(AEGIS). Among the 146 X-ray sources in this sample, 58% are classified
optically as emission-line AGNs, the rest as star-forming galaxies or
absorption-dominated galaxies. The latter are also known as "X-ray bright,
optically normal galaxies" (XBONGs). Analysis of the relationship between
optical emission lines and X-ray properties shows that the completeness of
optical AGN selection suffers from dependence on the star formation rate and
the quality of observed spectra. It also shows that XBONGs do not appear to be
a physically distinct population from other X-ray detected, emission-line AGNs.
On the other hand, X-ray AGN selection also has strong bias. About 2/3 of all
emission-line AGNs at L_bol>10^44 erg/s in our sample are not detected in our
200 ks Chandra images, most likely due to moderate or heavy absorption by gas
near the AGN. The 2--7 keV detection rate of Seyfert 2s at z~0.6 suggests that
their column density distribution and Compton-thick fraction are similar to
that of local Seyferts. Multiple sample selection techniques are needed to
obtain as complete a sample as possible.Comment: 24 pages, 14 figures, submitted to ApJ. Version 2 matches the ApJ
accepted version. Sec 3 was reorganized and partly rewritten with one
additional figure (Fig.3
Data and 2D scaling relations for galaxies in Abell 1689: a hint of size evolution at z~0.2
{abridged} We present imaging and spectroscopy of Abell 1689 (z=0.183) from
GEMINI/GMOS-N and HST/ACS. We measure integrated photometry from the GMOS g'
and r' images (for 531 galaxies) and surface photometry from the HST F625W
image (for 43 galaxies) as well as velocities and velocity dispersions from the
GMOS spectra (for 71 galaxies). We construct the Kormendy relation (KR),
Faber-Jackson relation (FJR) and colour-magnitude relation (CMR) for early-type
galaxies in Abell 1689 using this data and compare them to those of the Coma
cluster. We measure the intrinsic scatter of the CMR in Abell 1689 to be 0.054
\pm 0.004 mag which places degenerate constraints on the ratio of the assembly
timescale to the time available (beta) and the age of the population. Making
the assumption that galaxies in Abell 1689 will evolve into those of Coma over
an interval of 2.26 Gyr breaks this degeneracy and limits beta to be > 0.6 and
the age of the red sequence to be > 5.5 Gyr (formed at z > 0.55). Without
corrections for size evolution but accounting for magnitude cuts and selection
effects, the KR & FJR are inconsistent and disagree at the 2 sigma level
regarding the amount of luminosity evolution in the last 2.26 Gyr. However,
after correcting for size evolution the KR & FJR show similar changes in
luminosity (0.22 \pm 0.11 mag) that are consistent with the passive evolution
of the stellar populations from a single burst of star formation 10.2 \pm 3.3
Gyr ago (z = 1.8+inf-0.9). Thus the changes in the KR, FJR & CMR of Abell 1689
relative to Coma all agree and suggest old galaxy populations with little or no
synchronisation in the star formation histories. Furthermore, the weak evidence
for size evolution in the cluster environment in the last 2.26 Gyr places
interesting constraints on the possible mechanisms at work, favouring
harassment or secular processes over merger scenarios.Comment: Accepted for publication in MNRA
Propostes d'acció per a un model col·laboratiu entre serveis sanitaris i serveis socials bàsics
Serveis sanitaris; Serveis socials bàsics; Model d'acció i col·laboracióServicios sanitarios; Servicios sociales básicos; Modelo de acción y colaboraciónHealth services; Basic social services; Action and collaboration modelDocument que recull models d'acció i col·laboració entre els serveis sanitaris i els serveis socials amb l'objectiu de promoure estratègies conjuntes de treball entre tots dos sistemes per poder abordar els problemes comuns detectats
Search for CP Violation in the Decay Z -> b (b bar) g
About three million hadronic decays of the Z collected by ALEPH in the years
1991-1994 are used to search for anomalous CP violation beyond the Standard
Model in the decay Z -> b \bar{b} g. The study is performed by analyzing
angular correlations between the two quarks and the gluon in three-jet events
and by measuring the differential two-jet rate. No signal of CP violation is
found. For the combinations of anomalous CP violating couplings, and , limits of \hat{h}_b < 0.59h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st
Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the Universe
The Extragalactic Background Light (EBL) includes photons with wavelengths
from ultraviolet to infrared, which are effective at attenuating gamma rays
with energy above ~10 GeV during propagation from sources at cosmological
distances. This results in a redshift- and energy-dependent attenuation of the
gamma-ray flux of extragalactic sources such as blazars and Gamma-Ray Bursts
(GRBs). The Large Area Telescope onboard Fermi detects a sample of gamma-ray
blazars with redshift up to z~3, and GRBs with redshift up to z~4.3. Using
photons above 10 GeV collected by Fermi over more than one year of observations
for these sources, we investigate the effect of gamma-ray flux attenuation by
the EBL. We place upper limits on the gamma-ray opacity of the Universe at
various energies and redshifts, and compare this with predictions from
well-known EBL models. We find that an EBL intensity in the optical-ultraviolet
wavelengths as great as predicted by the "baseline" model of Stecker et al.
(2006) can be ruled out with high confidence.Comment: 42 pages, 12 figures, accepted version (24 Aug.2010) for publication
in ApJ; Contact authors: A. Bouvier, A. Chen, S. Raino, S. Razzaque, A.
Reimer, L.C. Reye
Neonatal outcomes of extremely preterm infants from the NICHD Neonatal Research Network.
OBJECTIVE: This report presents data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network on care of and morbidity and mortality rates for very low birth weight infants, according to gestational age (GA).
METHODS: Perinatal/neonatal data were collected for 9575 infants of extremely low GA (22-28 weeks) and very low birth weight (401-1500 g) who were born at network centers between January 1, 2003, and December 31, 2007.
RESULTS: Rates of survival to discharge increased with increasing GA (6% at 22 weeks and 92% at 28 weeks); 1060 infants died at
CONCLUSION: Although the majority of infants with GAs of \u3eor=24 weeks survive, high rates of morbidity among survivors continue to be observed
Efficacy of CDK4/6 inhibitors in preclinical models of malignant pleural mesothelioma
Background There is no effective therapy for patients with malignant pleural mesothelioma (MPM) who progressed to platinum-based chemotherapy and immunotherapy. Methods We aimed to investigate the antitumor activity of CDK4/6 inhibitors using in vitro and in vivo preclinical models of MPM. Results Based on publicly available transcriptomic data of MPM, patients with CDK4 or CDK6 overexpression had shorter overall survival. Treatment with abemaciclib or palbociclib at 100 nM significantly decreased cell proliferation in all cell models evaluated. Both CDK4/6 inhibitors significantly induced G1 cell cycle arrest, thereby increasing cell senescence and increased the expression of interferon signalling pathway and tumour antigen presentation process in culture models of MPM. In vivo preclinical studies showed that palbociclib significantly reduced tumour growth and prolonged overall survival using distinct xenograft models of MPM implanted in athymic mice. Conclusions Treatment of MPM with CDK4/6 inhibitors decreased cell proliferation, mainly by promoting cell cycle arrest at G1 and by induction of cell senescence. Our preclinical studies provide evidence for evaluating CDK4/6 inhibitors in the clinic for the treatment of MPM
Incidence, management, and outcomes of cardiovascular insufficiency in critically ill term and late preterm newborn infants
OBJECTIVE:
The objective of this study was to characterize the incidence, management, and short-term outcomes of cardiovascular insufficiency (CVI) in mechanically ventilated newborns, evaluating four separate prespecified definitions.
STUDY DESIGN:
Multicenter, prospective cohort study of infants ≥34 weeks gestational age (GA) and on mechanical ventilation during the first 72 hours. CVI was prospectively defined as either (1) mean arterial pressure (MAP) < GA; (2) MAP < GA + signs of inadequate perfusion; (3) any therapy for CVI; or (4) inotropic therapy. Short-term outcomes included death, days on ventilation, oxygen, and to full feedings and discharge.
RESULTS:
Of 647 who met inclusion criteria, 419 (65%) met ≥1 definition of CVI. Of these, 98% received fluid boluses, 36% inotropes, and 17% corticosteroids. Of treated infants, 46% did not have CVI as defined by a MAP < GA ± signs of inadequate perfusion. Inotropic therapy was associated with increased mortality (11.1 vs. 1.3%; p < 0.05).
CONCLUSION:
More than half of the infants met at least one definition of CVI. However, almost half of the treated infants met none of the definitions. Inotropic therapy was associated with increased mortality. These findings can help guide the design of future studies of CVI in newborn
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