263 research outputs found
Val247Leu beta2-glycoprotein-I allelic variant is associated with antiphospholipid syndrome: Systematic review and meta-analysis
[EN] Previous studies have suggested that the possession of the Val/Val genotype of the Val247Leu
polymorphism of the β2-glycoproteinI (β2-GPI) gene may be associated with antiphospholipid syndrome
(APS), and, among patients with APS, with the production of anti-β2-GPI antibodies or the development of
thrombosis. Given the controversial results reported, the aim of this work is to combine previous findings
by means of a systematic review and a meta-analysis.
Methods: We retrieved studies analyzing the genotype of the above-mentioned polymorphism among patients with APS by means of electronic database search. A meta-analysis was conducted in a random effects
model and calculations of odds ratio (OR) and confidence intervals (CI) were done. Sensitivity analysis and
tests for heterogeneity of the results were performed.
Results: Eight previous studies analyzed the association of APS, anti-β2-GPI antibodies and/or thrombosis with the
Val247Leu polymorphism. After meta-analysis, patients with APS had a significantly higher prevalence of the Val/
Val genotype of this genetic variant when compared with controls (OR=2.04; 95% CI: 1.12, 3.73; P=0.02). Among
patients with APS, those with anti-β2-GPI antibodies had a higher prevalence of this genotype (OR=1.73; 95% CI:
1.04, 2.87; P=0.03). No significant results were found for the presence of arterial or venous thrombosis.
Conclusions: Val/Val genotype of β2-GPI gene is associated with a significant excess risk to suffer from APS and,
among patients with APS, to have anti-β2-GPI antibodies. No definite conclusions can be made regarding the association of this polymorphism with thrombosis among APS patients.
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Anisotropic Diffusion Filter with Memory based on Speckle Statistics for Ultrasound Images
Ultrasound imaging exhibits considerable difficulties for medical visual inspection and for the development of automatic
analysis methods due to speckle, which negatively affects the perception of tissue boundaries and the performance of automatic
segmentation methods. With the aim of alleviating the effect of speckle, many filtering techniques are usually considered as a
preprocessing step prior to automatic analysis methods or visual inspection. Most of the state-of-the-art filters try to reduce the
speckle effect without considering its relevance for the characterization of tissue nature. However, the speckle phenomenon is the
inherent response of echo signals in tissues and can provide important features for clinical purposes. This loss of information
is even magnified due to the iterative process of some speckle filters, e.g., diffusion filters, which tend to produce over-filtering
because of the progressive loss of relevant information for diagnostic purposes during the diffusion process. In this work, we
propose an anisotropic diffusion filter with a probabilistic-driven memory mechanism to overcome the over-filtering problem by
following a tissue selective philosophy. Specifically, we formulate the memory mechanism as a delay differential equation for
the diffusion tensor whose behavior depends on the statistics of the tissues, by accelerating the diffusion process in meaningless
regions and including the memory effect in regions where relevant details should be preserved. Results both in synthetic and real
US images support the inclusion of the probabilistic memory mechanism for maintaining clinical relevant structures, which are
removed by the state-of-the-art filters
Non-Rigid Groupwise Registration for Motion Estimation and Compensation in Compressed Sensing Reconstruc- tion of Breath-Hold Cardiac Cine MRI
Purpose: Compressed sensing methods with motion estimation and compensation techniques
have been proposed for the reconstruction of accelerated dynamic MRI. However, artifacts that
naturally arise in compressed sensing reconstruction procedures hinder the estimation of motion
from reconstructed images, especially at high acceleration factors. This work introduces a robust
groupwise non-rigid motion estimation technique applied to the compressed sensing reconstruction
of dynamic cardiac cine MRI sequences.
Theory and Methods: A spatio-temporal regularized, groupwise, non-rigid registration method
based on a B-splines deformation model and a least squares metric is used to estimate and to
compensate the movement of the heart in breath-hold cine acquisitions and to obtain a quasi-static
sequence with highly sparse representation in temporally transformed domains.
Results: Short axis in vivo datasets are used for validation, both original multi-coil as well as
DICOM data. Fully sampled data were retrospectively undersampled with various acceleration
factors and reconstructions were compared with the two well-known methods k-t FOCUSS and
MASTeR. The proposed method achieves higher signal to error ratio and structure similarity index
for medium to high acceleration factors.
Conclusions: Reconstruction methods based on groupwise registration show higher quality recon-
structions for cardiac cine images than the pairwise counterparts tested
Multi-Oriented Windowed Harmonic Phase Reconstruction for Robust Cardiac Strain Imaging
The purpose of this work is to develop a method for direct estimation of
the cardiac strain tensor by extending the harmonic phase reconstruction on
tagged magnetic resonance images to obtain more precise and robust measurements.
The extension relies on the reconstruction of the local phase of
the image by means of the windowed Fourier transform and the acquisition of
an overdetermined set of stripe orientations in order to avoid the phase interferences
from structures outside the myocardium and the instabilities arising
from the application of a gradient operator. Results have shown that increasing
the number of acquired orientations provides a signi cant improvement
in the reproducibility of the strain measurements and that the acquisition of
an extended set of orientations also improves the reproducibility when compared
with acquiring repeated samples from a smaller set of orientations.
Additionally, biases in local phase estimation when using the original harmonic
phase formulation are greatly diminished by the one here proposed.
The ideas here presented allow the design of new methods for motion sensitive
magnetic resonance imaging, which could simultaneously improve the
resolution, robustness and accuracy of motion estimates
The Effect of Lifestyle Intervention on Health-Related Quality of Life in Adults with Metabolic Syndrome: A Meta-Analysis
[EN] The aim of this meta-analysis was to assess the effects of a lifestyle intervention through health education on nutrition, physical activity, and healthy habits on physical and mental health-related quality of life (HRQoL), in adults with metabolic syndrome (MetS). The databases used were PubMed, WOS, and Scopus. The inclusion criteria were: observational, longitudinal and randomized clinical trial (RCT) study designs, adults (both sexes), with at least two criteria of MetS, lifestyle intervention and comparison with a control group, and a measurement of HRQoL with a validated questionnaire. We analyzed the Hedges’ g and SF-36 score. I2 statistics were calculated and possible publication and small study biases were assessed using Egger’s test and funnel plots. Seven RCTs were selected for meta-analysis, based on 637 study participants. Significant improvements were found in the physical dimensions of the HRQoL scores for subjects in the active intervention compared to the group that received general lifestyle information (Hedges’ g 0.61, 95% confidence interval (CI) = 0.31–0.91). Mental health-related quality of life was also significantly improved in the intervention group compared with the control group (Hedges’ g 0.84, 95% CI = 0.64–1.03). In conclusion, our results suggest that, according to the RCTs selected for this meta-analysis, a lifestyle intervention significantly improves HRQoL in all its domains.SIThis research was funded by Fondo de Investigación para la Salud (FIS), which is co-funded by the European Regional Development Fund grant PI17/00532
Native Trichoderma Isolates from Soil and Rootstock to Fusarium spp. Control and Growth Promotion of Humulus lupulus L. Plantlets
[EN] Fusarium genus is a wide host phytopathogen causing significant losses in multiple crops, including hops. There is limited information on the sustainable management of Fusarium spp. in hop fields. Trichoderma is an endophytic fungus used in agriculture as a biological control agent (BCA) and as a plant growth promoter. It has been used to antagonize Fusarium spp. in other crops. The objective of the current study was to identify indigenous hop field Trichoderma isolates with biocontrol and hop growth promotion capabilities. Three isolates of Fusarium and eleven autochthonous Trichoderma isolates collected from sustainable hop fields were evaluated in this work. Direct confrontation tests (the physical interaction between the pathogen and BCA and their competition for space and nutrient resources) and membrane tests (the capacity of the BCA to produce metabolites or enzymes through a cellophane film and inhibit the development of the pathogen) assessed the antagonism of these Trichoderma isolates against Fusarium culmorum, F. sambucinum, and F. oxysporum. A bioassay with hop plantlets inoculated with a spore suspension of Trichoderma was performed to assess its hop growth enhancement. T. hamatum (T311 and T324), T. virens T312, and T. gamsii T327 showed high growth inhibition of Fusarium spp. phytopathogens and high plant growth promotion. Native Trichoderma isolates from sustainable hop-producing soils have great potential as BCAs and hop growth promotersSIThis research was funded by the Ministerio de Universidades (Spain), grant number FPU19/03650 to A.J.P.-Á., and the Ministerio de Agricultura, Pesca y Alimentación (Spain), Quality Hops Operational Group, Innovations in the cultivation of hops in Spain to improve the sustainability of farms (2019/00179/001
Alfabetización y educación para la salud en personas con discapacidad mediante la formación en competencias profesionales
Memoria ID-108. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2018-2019
Multi-Stencil Streamline Fast Marching: a general 3D Framework to determine Myocardial Thickness and Transmurality in Late Enhancement Images
We propose a fully three-dimensional methodology
for the computation of myocardial non-viable tissue transmurality
in contrast enhanced magnetic resonance images. The outcome
is a continuous map defined within the myocardium where not
only current state-of-the-art measures of transmurality can be
calculated, but also information on the location of non-viable
tissue is preserved. The computation is done by means of a
partial differential equation framework we have called Multi-
Stencil Streamline Fast Marching (MSSFM). Using it, the myocardial
and scarred tissue thickness is simultaneously computed.
Experimental results show that the proposed 3D method allows
for the computation of transmurality in myocardial regions where
current 2D methods are not able to as conceived, and it also
provides more robust and accurate results in situations where the
assumptions on which current 2D methods are based —i.e., there
is a visible endocardial contour and its corresponding epicardial
points lie on the same slice—, are not met
The TRPM8 antagonist RGM8-51 displays analgesic activity in different pain models
TRPM8 channels are overexpressed in sensory neurons after nerve injury or
inflammation, resulting in enhanced sensitivity (allodynia and hyperalgesia) to physical
stimulation, and have been implicated in migraine, but the interest of TRPM8 antagonists
is still a matter of controversy (1,2). The aim of our work was to evaluate the analgesic
activity of a TRPM8 antagonist, RGM8-51, in different pain models, looking for
similarities and differences with other antagonists. To this end, we used the mouse
oxaliplatin-induced peripheral neuropathy, the chronic constriction injury of the rat
sciatic nerve (CCI) and mouse NTG-induced migraine-like models. Compound RGM8-
51 reduces the cold allodynia induced by oxaliplatin, from 15 to 60 min after
administration (0.1-1 μg, i.pl.), decreases the nocifensive responses to cold, heat and
mechanical stimuli in the CCI model (10 μg, i.pl., 30 mg/Kg, i.p.), and relief chronic pain
associated to migraine in mouse, in a sex-dependent manner (10 or 30 mg/Kg, i.v.). The
β–lactam derivative RGM8-51 not only has analgesic activity in all assayed animal
models, but also seems to have a different mode of interaction with the TRPM8 channel
than other antagonists, as suggested by docking studies
Fast 4D elastic group-wise image registration. Convolutional interpolation revisited
Background and Objective:This paper proposes a new and highly efficient implementation of 3D+t groupwise registration based on the free-form deformation paradigm. Methods:Deformation is posed as a cascade of 1D convolutions, achieving great reduction in execution time for evaluation of transformations and gradients. Results:The proposed method has been applied to 4D cardiac MRI and 4D thoracic CT monomodal datasets. Results show an average runtime reduction above 90%, both in CPU and GPU executions, compared with the classical tensor product formulation. Conclusions:Our implementation, although fully developed for the metric sum of squared differences, can be extended to other metrics and its adaptation to multiresolution strategies is straightforward. Therefore, it can be extremely useful to speed up image registration procedures in different applications where high dimensional data are involved.MEC-TEC2017-82408-
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