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Dysfunction of neurovascular/metabolic coupling in chronic focal epilepsy
In this study, we aim to evaluate the mechanisms underlying the neuro-vascular/metabolic coupling in the epileptogenic cortices of rats with chronic focal epilepsy. To that end, we first analyzed intracranial recordings (electrophysiology, laser Doppler flowmetry and optical imaging) obtained from the seizure onset zones during ictal periods and then used these data to fit a metabolically-coupled balloon model. This biophysical model is an extension of the standard balloon model with modulatory effects of changes in tissue oxygenation, capillary dynamics and variable O2 extraction fraction. As previously reported using acute seizure models, we found that there is a significant higher contribution from high local field potential frequency bands to the cerebral blood flow (CBF) responses in the epileptogenic cortices during ictal neuronal activities. The hemodynamic responses associated with ictal activities were distance-dependent with regard to the seizure focus, though varied in profiles from those obtained from acute seizure models. Parameters linking the CBF and relative concentration of deoxy-hemoglobin to neuronal activity in the biophysical model were significantly different between epileptic and normal rats. In particular, we found that the coefficient associated with the strength of the functional hyperemic response was significantly larger in the epileptogenic cortices, although changes in hemoglobin concentration associated with ictal activity reflected the existence of a significantly higher baseline for oxygen metabolism in the epileptogenic cortices
Simultaneous and optical follow-up GRB observations by BOOTES
Since 1998 BOOTES has provided follow-up observations for more than 70 GRBs; the most important results obtained so far are the detection of an OT in the GRB 000313 error box and the non-detection of optical emission simultaneous to the high-energy emission for several GRBs (both long/soft and short/hard events)
Detection of Leishmania infantum DNA mainly in Rhipicephalus sanguineus male ticks removed from dogs living in endemic areas of canine leishmaniosis
Background: Sand flies are the only biologically adapted vectors of Leishmania parasites, however, a possible role in the transmission of Leishmania has been proposed for other hematophagous ectoparasites such as ticks. In order to evaluate natural infection by Leishmania infantum in Rhipicephalus sanguineus ticks, taking into account its close association with dogs, 128 adult R. sanguineus ticks removed from 41 dogs living in endemic areas of canine leishmaniosis were studied. Methods: Individual DNA extraction was performed from each tick and whole blood taken from dogs. Dog sera were tested for IgG antibodies to L. infantum antigen by ELISA and L. infantum real-time PCR was performed from canine whole blood samples and ticks. Results: Leishmania infantum PCR was positive in 13 ticks (10.1%) including one female, (2.0%) and 12 males (15.2%), and in only five dogs (12.2%). Male ticks had a significantly higher infection rate when compared to female R. sanguineus. The percentage of L. infantum seroreactive dogs was 19.5%. All but two PCR positive dogs were seroreactive. Leishmania infantum PCR positive ticks were removed from seropositive and seronegative dogs with a variety of PCR results. Conclusions: This study demonstrates high prevalence of L. infantum DNA in R. sanguineus ticks removed from L. infantum seropositive and seronegative dogs. The presence of L. infantum DNA was detected mainly in male ticks possibly due to their ability to move between canine hosts and feed on several canine hosts during the adult life stage. Additional studies are needed to further explore the role of R. sanguineus ticks and in particular, male adults, in both the epidemiology and immunology of L. infantum infection in dogs in endemic areas
Planetary Nebulae: Observational Properties, Mimics, and Diagnostics
The total number of true, likely and possible planetary nebulae (PN) now
known in the Milky Way is nearly 3000, double the number known a decade ago.
The new discoveries are a legacy of the recent availability of wide field,
narrowband imaging surveys, primarily in the light of H-alpha. In this paper,
we summarise the various PN discovery techniques, and give an overview of the
many types of objects which mimic PN and which appear as contaminants in both
Galactic and extragalactic samples. Much improved discrimination of classical
PN from their mimics is now possible based on the wide variety of high-quality
multiwavelength data sets that are now available. We offer improved taxonomic
and observational definitions for the PN phenomenon based on evaluation of
these better diagnostic capabilities. However, we note that evidence is
increasing that the PN phenomenon is heterogeneous, and PN are likely to be
formed from multiple evolutionary scenarios. In particular, the relationships
between some collimated symbiotic outflows and bipolar PN remain uncertain.Comment: 25 pages, 6 figures; presentation at the workshop on the Legacies of
the Macquarie/AAO/Strasbourg H-alpha Planetary Nebula project, accepted by
the Publications of the Astronomical Society of Australia (PASA
Radio continuum emission from knots in the DG Tau jet
Context: HH 158, the jet from the young star DG Tau, is one of the few
sources of its type where jet knots have been detected at optical and X-ray
wavelengths. Aims: To search, using Very Large Array observations of this
source, radio knots and if detected, compare them with the optical and X-ray
knots. To model the emission from the radio knots. Methods: We analyzed archive
data and also obtained new Very Large Array observations of this source, as
well as an optical image, to measure the present position of the knots. We also
modeled the radio emission from the knots in terms of shocks in a jet with
intrinsically time-dependent ejection velocities. Results: We detected radio
knots in the 1996.98 and 2009.62 VLA data. These radio knots are,within error,
coincident with optical knots. We also modeled satisfactorily the observed
radio flux densities as shock features from a jet with intrinsic variability.
All the observed radio, optical, and X-ray knot positions can be intepreted as
four successive knots, ejected with a period of 4.80 years and traveling away
from the source with a velocity of 198 km s in the plane of the sky.
Conclusions: The radio and optical knots are spatially correlated and our model
can explain the observed radio flux densities. However, the X-ray knots do not
appear to have optical or radio counterparts and their nature remains poorly
understood.Comment: 8 pages, 8 figures, to appear in Astronomy & Astrophysic
Morbidity, outcomes and cost-benefit analysis of wildlife rehabilitation in Catalonia (Spain)
Background There are few studies of careful examination of wildlife casualties in Wildlife Rehabilitation Centers. These studies are essential for detecting menaces to wild species and providing objective criteria about cost-benefit of treatments in those centers. The release rate is considered the main outcome indicator, but other parameters such as length of stay at the center and a cost-benefit index expressed as number of released animals per euro and day, could be used as reliable estimators of the rehabilitation costs. Methodology A retrospective study based on 54772 admissions recorded from 1995-2013 in the database of the Wildlife Rehabilitation Center of Torreferrussa (Catalonia, NW Spain) assessed the morbidity, outcomes and cost-benefits of the rehabilitation practices. Results Three hundred and two species were included: 232 birds (n = 48633), 37 mammals (n = 3293), 20 reptiles (n = 2705) and 13 amphibians (n = 141). The most frequent causes of admission were: 39.8% confiscation of protected species (89.4% passerines), 31.8% orphaned young animals (35.3% swifts, 21.7% diurnal raptors and owls) and 17.4% trauma casualties (46.7% raptors and owls). The highest proportion of releases was found in the captivity confiscation category [87.4% passerines (median time of stay: 12 days)], followed by the orphaned category [78% owls (66 days), 76.5% diurnal birds of prey (43 days), 75.6% hedgehogs (49 days), 52.7% swifts (19 days) and 52% bats (55 days)]. For the trauma group, 46.8% of releases were hedgehogs (44 days) and 25.6% owls (103 days). As regards the cost-benefit index, the trauma casualties and infectious diseases had the worse values with 1.3 and 1.4 released animals/euro/day respectively, and were particularly low in raptors, waders, marine birds and chiroptera. On the contrary, captivity (4.6) and misplacement (4.1) had the best index, particulary in amphibian, reptiles and passerines. Conclusions/significance Cost-benefit studies including the release rate, the time of stay at the center and the costbenefit index should be implemented for improving management efficiency of the Wildlife Rehabilitation Centers
Ionization Structure and Spectra of Iron in Gaseous Nebulae}
The emission spectra and the ionization structure of the low ionization
stages of iron, Fe I--IV, in gaseous nebulae are studied. This work includes:
(i) new atomic data: photoionization cross sections, total e-ion recombination
rates, excitation collision strengths, and transition probabilities; (ii)
detailed study of excitation mechanisms for the [Fe II], [Fe III], and [Fe IV]
emission, and spectroscopic analysis of the observed IR, optical, and UV
spectra; (iii) study of the physical structure and kinematics of the nebulae
and their ionization fronts. Spectral analysis of the well observed Orion
nebula is carried out as a test case, using extensive collisional-radiative and
photoionization models. It is shown that the [Fe II] emission from the Orion
nebula is predominantly excited via electron collisions in high density
partially ionized zones; radiative fluorescence is relatively less effective.
Further evidence for high density zones is derived from the [O I] and [Ni II]
spectral lines, as well as from the kinematic measurements of ionic species in
the nebula. The ionization structure of iron in Orion is modeled using the
newly calculated atomic data, showing some significant differences from
previous models. The new model suggests a fully ionized H II region at
densities on the order of cm, and a dynamic partially ionized H
II/H I region at densities of \cm3. Photoionization models also
indicate that the optical [O I] and [Fe II] emission originates in high density
partially ionized regions within ionization fronts. The gas phase iron
abundance in Orion is estimated from observed spectra.Comment: AAS LaTex, 60 pages 18 figures. Astrophysical Journal. in pres
The Structure of the Planetary Nebula NGC 2371 in the Visible and Mid-Infrared
We investigate the structure of the planetary nebula (PN) NGC 2371 using
[OIII]-5007 imaging taken with the Jacobus Kapteyn 1.0 m telescope, and
[NII]-6584, [OIII]-5007 and Ha results acquired with the Hubble Space Telescope
(HST). These are supplemented with archival mid-infrared (MIR) observations
taken with the Spitzer Space Telescope (Spitzer). We note the presence of
off-axis low-ionization spokes along a PA of 65 degrees, and associated collars
of enhanced [OIII] emission. The spokes appear to consist of dense
condensations having low-excitation tails, possibly arising due to UV shadowing
and/or ram-pressure stripping of material. Line ratios imply that most of the
emission arises through photo-ionisation, and is unlikely to derive from
post-shock cooling regions. An analysis of these features in the MIR suggests
that they may also be associated with high levels of emission from polycyclic
aromatic hydrocarbons (PAHs), together with various permitted and forbidden
line transitions. Such high levels of PAH emission, where they are confirmed,
may develop as a result of preferentially enhanced FUV pumping of the
molecules, or shattering of larger grains within local shocks. Although H2
emission may also contribute to these trends, it is argued that shock-excited
transitions would lead to markedly differing results. We finally note that thin
filaments and ridges of [OIII] emission may indicate the presence of shock
activity at the limits of the interior envelope, as well as at various
positions within the shell itself. We also note that radially increasing fluxes
at 3.6, 5.8 and 8.0 microns, relative to the emission at 4.5 microns, may arise
due to enhanced PAH emission in external photo-dissociative regions (PDRs).Comment: 11 figures and 38 pages in arXiv. Accepted for publication in MNRA
Hospital-acquired influenza infections detected by a surveillance system over six seasons, from 2010/2011 to 2015/2016
In addition to outbreaks of nosocomial influenza, sporadic nosocomial influenza infections also occur but are generally not reported in the literature. This study aimed to determine the epidemiologic characteristics of cases of nosocomial influenza compared with the remaining severe cases of severe influenza in acute hospitals in Catalonia (Spain) which were identified by surveillance. An observational case-case epidemiological study was carried out in patients aged â„18 years from Catalan 12 hospitals between 2010 and 2016. For each laboratory-confirmed influenza case (nosocomial or not) we collected demographic, virological and clinical characteristics. We defined patients with nosocomial influenza as those admitted to a hospital for a reason other than acute respiratory infection in whom ILI symptoms developed â„48 h after admission and influenza virus infection was confirmed using RT-PCR. Mixed-effects regression was used to estimate the crude and adjusted OR. One thousand seven hundred twenty-two hospitalized patients with severe laboratory-confirmed influenza virus infection were included: 96 (5.6%) were classified as nosocomial influenza and more frequently had > 14 days of hospital stay (42.7% vs. 27.7%, P <.001) and higher mortality (18.8% vs. 12.6%, P <.02). The variables associated with nosocomial influenza cases in acute-care hospital settings were chronic renal disease (aOR 2.44 95% CI 1.44-4.15) and immunodeficiency (aOR 1.79 95% CI 1.04-3.06). Nosocomial infections are a recurring problem associated with high rates of chronic diseases and death. These findings underline the need for adherence to infection control guidelines
Multiplex protein profiling of bronchial aspirates reveals disease-, mortality- and respiratory sequelae-associated signatures in critically ill patients with ARDS secondary to SARS-CoV-2 infection
IntroductionBronchial aspirates (BAS) obtained during invasive mechanical ventilation (IMV) constitutes a useful tool for molecular phenotyping and decision making.AimTo identify the proteomic determinants associated with disease pathogenesis, all-cause mortality and respiratory sequelae in BAS samples from critically ill patients with SARS-CoV-2-induced ARDSMethodsMulticenter study including 74 critically ill patients with COVID-19 and non-COVID-19 ARDS. BAS were obtained by bronchoaspiration after IMV initiation. Three hundred sixty-four proteins were quantified using proximity extension assay (PEA) technology. Random forest models were used to assess predictor importance.ResultsAfter adjusting for confounding factors, CST5, NADK, SRPK2 and TGF-α were differentially detected in COVID-19 and non-COVID-19 patients. In random forest models for COVID-19, CST5, DPP7, NADK, KYAT1 and TYMP showed the highest variable importance. In COVID-19 patients, reduced levels of ENTPD2 and PTN were observed in nonsurvivors of ICU stay, even after adjustment. AGR2, NQO2, IL-1α, OSM and TRAIL showed the strongest associations with in-ICU mortality and were used to construct a protein-based prediction model. Kaplan-Meier curves revealed a clear separation in mortality risk between subgroups of PTN, ENTPD2 and the prediction model. Cox regression models supported these findings. In survivors, the levels of FCRL1, NTF4 and THOP1 in BAS samples obtained during the ICU stay correlated with lung function (i.e., DLCO levels) 3 months after hospital discharge. Similarly, Flt3L and THOP1 levels were correlated with radiological features (i.e., TSS). These proteins are expressed in immune and nonimmune lung cells. Poor host response to viral infectivity and an inappropriate reparative mechanism seem to be linked with the pathogenesis of the disease and fatal outcomes, respectively.ConclusionBAS proteomics identified novel factors associated with the pathology of SARS-CoV-2-induced ARDS and its adverse outcomes. BAS-based protein testing emerges as a novel tool for risk assessment in the ICU
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