6,381 research outputs found
Highly syntenic and yet divergent: a tale of two Theilerias
The published genomic sequences of the two major host-transforming Theileria species of cattle represent a rich resource of information that has allowed novel bioinformatic and experimental studies into these important apicomplexan parasites. Since their publication in 2005, the genomes of T. annulata and T. parva have been utilised for a diverse range of applications, ranging from candidate antigen discovery to the identification of genetic markers for population analysis. This has led to advancements in the quest for a sub-unit vaccine, while providing a greater understanding of variation among parasite populations in the field. The unique ability of these Theileria species to induce host cell transformation is the subject of considerable scientific interest and the availability of full genomic sequences has provided new insights into this area of research. This article reviews the data underlying published comparative analyses, focussing on the general features of gene expression, the major Tpr/Tar multi-copy gene family and a re-examination of the predicted macroschizont secretome. Codon usage between the Theileria species is reviewed in detail, as this underpins ongoing comparative studies investigating selection at the intra- and inter-species level. The TashAT/TpshAT family of genes, conserved between T. annulata and T. parva, encodes products targeted to the host nucleus and has been implicated in contributing to the transformed bovine phenotype. Species-specific expansion and diversification at this critical locus is discussed with reference to the availability, in the near future, of genomic datasets which are based on non-transforming Theileria species
Acute oral sodium propionate supplementation raises resting energy expenditure and lipid oxidation in fasted humans
Short chain fatty acids (SCFAs), produced from fermentation of dietary fibre by the gut microbiota, have been suggested to modulate energy metabolism. Previous work using rodent models have demonstrated that oral supplementation of the SCFA propionate raises resting energy expenditure (REE) by promoting lipid oxidation. The objective of this study was to investigate the effects of oral sodium propionate on REE and substrate metabolism in humans. Eighteen healthy volunteers (9 females and 9 males; Age: 25±1 y; Body Mass Index: 24.1±1.2 kg/m2) completed two study visits following an overnight fast. Tablets containing a total of 6845mg sodium propionate or 4164mg sodium chloride were provided over the 180 min study period in a random order. REE and substrate oxidation was assessed by indirect calorimetry. Oral sodium propionate administration increased REE (0.045±0.020 kcal/min; P=0.036) accompanied with elevated rates of whole-body lipid oxidation (0.012 ± 0.006 g/min; P=0.048) and independent of changes in glucose and insulin concentrations. Future studies are warranted to determine whether the acute effects of oral sodium propionate on REE translate into positive improvements in long-term energy balance in humans
Results of the MRI substudy of the intravenous magnesium efficacy in stroke trial
<p><b>Background and Purpose:</b>Although magnesium is neuroprotective in animal stroke models, no clinical benefit was confirmed in the Intravenous Magnesium Efficacy in Stroke (IMAGES) trial of acute stroke patients. The Magnetic
Resonance in IMAGES (MR IMAGES) substudy investigated the effects of magnesium on the imaging surrogate
outcome of infarct growth.</p>
<p><b>Methods:</b> IMAGES trial patients in participating centers were randomized to receive either intravenous magnesium or placebo within 12 hours of stroke onset. Infarct growth was defined as volume difference between baseline diffusion-weighted imaging and day 90 fluid-attenuated inversion recovery image lesions. Patients who died were imputed the largest infarct growth observed.</p>
<p><b>Results:</b> Among the 90 patients included in the primary analysis, there was no difference in infarct growth (median absolute growth, P=0.639; median percentage growth, P=0.616; proportion with any growth, P=0.212) between the
46 treated with magnesium and 44 with placebo. Infarct growth correlated with NIHSS score change from baseline to
day 90. There was a trend showing baseline serum glucose correlated with infarct growth with magnesium treatment,
but not in the placebo group. The mismatch frequency was reduced from 73% to 47% by increasing the mismatch
threshold from >20% to >100% of core volume.</p>
<p><b>Conclusions:</b> Infarct growth, confirmed here as a surrogate for clinical progression, was similar between magnesium and placebo treatment, paralleling the main IMAGES trial clinical outcomes. Glucose was a covariate for infarct growth with magnesium treatment. A more stringent mismatch threshold to define penumbra more appropriately would have
excluded half of the patients in this 12-hour time window stroke study.</p>
Co-Participation In Oral Paired Interviews: Preliminary Findings Of The OPENPAU Project
The Ministry of Education is changing how Spanish University Entrance Examination (PAU) will be delivered in 2017. To test the construct, experimental oral interviews with potential candidates of the PAU were done. Purpose of Study: The research observed whether paired interviews favored the delivery and organization of the PAU test and if this type of delivery favors the students¿ performance. This paper studies how students in paired interviews outperform the individual. Sources of Evidence: About ten interviews were delivered in the US and about 40 in Spain. They all were recorded and analyzed from the interaction and output quality. Analysis and results: The study indicates that co-construction of output may favor communication and improve the student¿s individual performance
Genomic islands of divergence in the Yellow Tang and the Brushtail Tang Surgeonfishes.
The current ease of obtaining thousands of molecular markers challenges the notion that full phylogenetic concordance, as proposed by phylogenetic species concepts, is a requirement for defining species delimitations. Indeed, the presence of genomic islands of divergence, which may be the cause, or in some cases the consequence, of speciation, precludes concordance. Here, we explore this issue using thousands of RAD markers on two sister species of surgeonfishes (Teleostei: Acanthuridae), Zebrasoma flavescens and Z. scopas, and several populations within each species. Species are readily distinguished based on their colors (solid yellow and solid brown, respectively), yet populations and species are neither distinguishable using mitochondrial markers (cytochrome c oxidase 1), nor using 5193 SNPs (pairwise Φst = 0.034). In contrast, when using outlier loci, some of them presumably under selection, species delimitations, and strong population structure follow recognized taxonomic positions (pairwise Φst = 0.326). Species and population delimitation differences based on neutral and selected markers are likely due to local adaptation, thus being consistent with the idea that these genomic islands of divergence arose as a consequence of isolation. These findings, which are not unique, raise the question of a potentially important pathway of divergence based on local adaptation that is only evident when looking at thousands of loci
Surgical excision of post-traumatic myositis ossificans of the adductor longus in a football player
A football player was diagnosed with myositis ossificans of his right adductor longus muscle after an acute injury. Conservative treatment failed and 1 year after the initial trauma the patient underwent surgical excision of a large ossification. Seven months postoperatively, the patient was fully recovered and returned to his preinjury activity levels. We present our approach to this case and discuss our considerations, referring to background information about this rare disease
Whooping crane (Grus americana) demography and environmental factors in a population growth simulation model
The Whooping Crane (Grus americana) is among North AmericaÂs most
charismatic species. Between 1938 and 2004, the population that migrates between
Aransas National Wildlife Refuge (ANWR) and Wood Buffalo National Park (WBNP),
grew from 18 to 217 individuals. The recovery plan objective for this endangered
species is to downlist the population in 2035, but this requires interpretive assessment of
population responses to environmental factors over the long term. I analyzed 27 years of
banding data, 37 years of nest monitoring data, and 20 years of winter reports to estimate
age-specific mortality and fecundity rates. The resulting life table yielded an intrinsic
rate of increase (r) of 0.14/y, a net reproductive rate (Ro) of 6.4/y, and a mean length of
a generation (G) of 13y.
Path analysis of environmental factors, demographic variables (natality and
mortality), and the finite rate of population increase (lambda) showed that annual
mortality, temperatures from the ANWR, WBNP and at a migration stop-over in Nebraska, and pond water depth were good predictors of lambda variability. However,
other environmental factors were significantly correlated: at ANWR, October- March
temperature (extreme minimum and maximum), December temperature (mean and
extreme minimum), November-January precipitation, and September-March freshwater
inflow; at WBNP, March-September precipitation, March-May temperature, and
temperatures during the September - October fall migration. The Pacific Decadal
Oscillation (PDO) affected lambda indirectly through environmental factors in Nebraska
and ANWR.
I graphically analyzed relevant data trends from 1967 to 2004 to identify the
relation between phases of PDO and environmental and demographic variables. During
PDO cold phases, a synchronization of Âextreme environmental values was observed
from the different regions; during warm phases extreme environmental values were
scattered. Most periods of Whooping Crane population decline happened during cold
phases.
I developed a compartment model to represent Whooping Crane population
dynamics utilizing the new data on survivorship and fecundity from banded birds. The
model was capable of simulating historical population trends with adjustments in brood
success and egg mortality. The model will allow future studies to test population
responses to various environmental scenarios at the WBNP, during fall and spring
migrations, and at the ANWR
Atmospheric PSF Interpolation for Weak Lensing in Short Exposure Imaging Data
A main science goal for the Large Synoptic Survey Telescope (LSST) is to
measure the cosmic shear signal from weak lensing to extreme accuracy. One
difficulty, however, is that with the short exposure time (15 seconds)
proposed, the spatial variation of the Point Spread Function (PSF) shapes may
be dominated by the atmosphere, in addition to optics errors. While optics
errors mainly cause the PSF to vary on angular scales similar or larger than a
single CCD sensor, the atmosphere generates stochastic structures on a wide
range of angular scales. It thus becomes a challenge to infer the multi-scale,
complex atmospheric PSF patterns by interpolating the sparsely sampled stars in
the field. In this paper we present a new method, PSFent, for interpolating the
PSF shape parameters, based on reconstructing underlying shape parameter maps
with a multi-scale maximum entropy algorithm. We demonstrate, using images from
the LSST Photon Simulator, the performance of our approach relative to a
5th-order polynomial fit (representing the current standard) and a simple
boxcar smoothing technique. Quantitatively, PSFent predicts more accurate PSF
models in all scenarios and the residual PSF errors are spatially less
correlated. This improvement in PSF interpolation leads to a factor of 3.5
lower systematic errors in the shear power spectrum on scales smaller than
, compared to polynomial fitting. We estimate that with PSFent and for
stellar densities greater than , the spurious shear
correlation from PSF interpolation, after combining a complete 10-year dataset
from LSST, is lower than the corresponding statistical uncertainties on the
cosmic shear power spectrum, even under a conservative scenario.Comment: 18 pages,12 figures, accepted by MNRA
Effects of canagliflozin on serum potassium in the CANagliflozin cardioVascular Assessment Study (CANVAS) Program
Background: The sodium-glucose cotransporter 2 inhibitor canagliflozin has been shown to reduce the risk of cardiovascular and renal events in patients with Type 2 diabetes mellitus and high risk. Pooled analyses of data from early studies and interim data from the CANagliflozin cardioVascular Assessment Study (CANVAS) suggested that canagliflozin might lead to increases in serum potassium, particularly the 300 mg dose in patients with renal impairment, which is important because high serum potassium is associated with increased cardiovascular and renal risk. We examined the effect of canagliflozin on serum potassium levels and hyperkalemia rates in the completed CANVAS Program. Methods: The CANVAS Program (n = 10,142) was comprised of two comparable double-blind, randomized, placebo-controlled trials (CANVAS and CANVAS-Renal). Participants received canagliflozin 100 or 300 mg or placebo. Serum potassium measurements were performed in a central laboratory0 and assessed at ∼6-month intervals. Results: In the CANVAS Program, mean potassium levels were generally consistent with canagliflozin and placebo, overall and by baseline estimated glomerular filtration rate (eGFR; ≥60, 45 to<60 and <45 mL/min/1.73 m2). The risk of increased or decreased potassium was similar with canagliflozin and placebo overall and by baseline eGFR (all P-heterogeneity ≥0.56) or use of renin-angiotensin-aldosterone system inhibitors (all P-heterogeneity ≥0.71); levels did not appear different by canagliflozin dose. Hyperkalemia {hazard ratio (HR) [95% confidence interval (CI)] 1.60 (0.92-2.81)} and serious hyperkalemia [HR (95% CI) 0.75 (0.27-2.11)] adverse events were not different across groups. Conclusions: In the CANVAS Program, there were no meaningful effects of canagliflozin on serum potassium in the overall population or key subgroups. Hyperkalemia adverse events were uncommon and occurred at comparable rates with canagliflozin and placebo
One-year follow-up of a randomised controlled trial on added splinting to eccentric exercises in chronic midportion Achilles tendinopathy
OBJECTIVE: The study examined whether the addition of a night splint to eccentric exercises is beneficial for functional outcome in chronic mid-portion Achilles tendinopathy. DESIGN: One-year follow-up of a randomised controlled single blinded clinical trial. SETTING: Sports medicine department in a general hospital. PATIENTS: 58 patients (70 tendons) were included. INTERVENTIONS: All patients completed a 12-week heavy load eccentric training programme. One group received a night splint in addition to eccentric exercises. Main outcome measurements: Outcome scores were: Victorian Institute of Sport Assessment - Achilles (VISA-A) score, subjective patient satisfaction and neovascularisation score measured with Power Doppler Ultrasonography. RESULTS: For both groups the VISA-A score increased significantly (from 50 to 76 (P < 0.01) in the eccentric group and from 49 to 78 (P < 0.01) in the night splint group). No significant differences in VISA-A score were found between the groups from baseline to one year (P = 0.32). Presence of neovessels at baseline did not predict change in VISA-A score after one year in the whole group (P = 0.71). CONCLUSION: Eccentric exercises with or without a night splint improved functional outcome at one-year follow-up. At follow-up there
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