Abelherskind4878
The level of RF-induced heating during an MR scan is affected significantly by RF coupling when more than one wire-like implant is present. In some of the configurations studied, the heating was increased by the presence of a second conductor partially immersed in the phantom. Thus, RF coupling is an important factor to consider in the assessment of safety issues for MRI when multiple implants are present.
The level of RF-induced heating during an MR scan is affected significantly by RF coupling when more than one wire-like implant is present. In some of the configurations studied, the heating was increased by the presence of a second conductor partially immersed in the phantom. Thus, RF coupling is an important factor to consider in the assessment of safety issues for MRI when multiple implants are present.
To develop a 3D UNET convolutional neural network for rapid extraction of myelin water fraction (MWF) maps from six-echo fast acquisition with spiral trajectory and T
-prep data and to evaluate its accuracy in comparison with multilayer perceptron (MLP) network.
The MWF maps were extracted from 138 patients with multiple sclerosis using an iterative three-pool nonlinear least-squares algorithm (NLLS) without and with spatial regularization (srNLLS), which were used as ground-truth labels to train, validate, and test UNET and MLP networks as a means to accelerate data fitting. Network testing was performed in 63 patients with multiple sclerosis and a numerically simulated brain phantom at SNR of 200, 100 and 50.
Simulations showed that UNET reduced the MWF mean absolute error by 30.1% to 56.4% and 16.8% to 53.6% over the whole brain and by 41.2% to 54.4% and 21.4% to 49.4% over the lesions for predicting srNLLS and NLLS MWF, respectively, compared to MLP, with better performance at lower SNRs. UNET also outperformed MLP for predicting srNLLS MWF in the in vivo multiple-sclerosis brain data, reducing mean absolute error over the whole brain by 61.9% and over the lesions by 67.5%. However, MLP yielded 41.1% and 51.7% lower mean absolute error for predicting in vivo NLLS MWF over the whole brain and the lesions, respectively, compared with UNET. The whole-brain MWF processing time using a GPU was 0.64 seconds for UNET and 0.74 seconds for MLP.
Subsecond whole-brain MWF extraction from fast acquisition with spiral trajectory and T
-prep data using UNET is feasible and provides better accuracy than MLP for predicting MWF output of srNLLS algorithm.
Subsecond whole-brain MWF extraction from fast acquisition with spiral trajectory and T2 -prep data using UNET is feasible and provides better accuracy than MLP for predicting MWF output of srNLLS algorithm.
Wrapping of the ascending aorta (AA), isolated or associated with aortoplasty, has never been completely accepted. Some complications, as folding of the aortic wall, compression of the vasa vasorum and changes in the flow pattern, with consequent dilatation of the proximal arch, have been described. We used fresh autologous pericardium (FAP), so far never reported, to wrap the AA, with the aim to stabilize its size when moderately dilated, maintaining the preoperative dimension or limiting the reduction to a few millimeters.
From 2015 to 2019, 10 patients, who were operated on for valve or coronary surgery or both, underwent wrapping of the AA with FAP. Mean age was 69 ± 7 years and EuroSCORE II 3.5 ± 1.7. Four patients had moderately impaired ejection fraction (35%-49%).
There was no early or late mortality. One patient was reoperated on after 48 months for severe mitral regurgitation. At a follow-up of 53 ± 14 months, a transthoracic echocardiogram showed that the AA size reduced slightly but significantly, from 45.2 ± 2.0 to 42.5 ± 4.1 mm, p = .03. The diameter of the proximal arch remained unchanged, from 37.1 ± 1.6 to 36.3 ± 2.9 mm, p = .20.
In the presence of moderately dilated AA, wrapping can be a reasonable option. The use of FAP stabilizes the size of the aorta after a follow-up of 53 months. Maintaining a size similar to the preoperative one avoids the complications related to the procedure.
In the presence of moderately dilated AA, wrapping can be a reasonable option. The use of FAP stabilizes the size of the aorta after a follow-up of 53 months. Maintaining a size similar to the preoperative one avoids the complications related to the procedure.
To design a b value and first-order motion moment (M
) optimized data acquisition for repeatable intravoxel incoherent motion (IVIM) quantification in the liver.
Cramer-Rao lower bound optimization was performed to determine optimal monopolar and optimal 2D samplings of the b-M
space based on noise performance. Monte Carlo simulations were used to evaluate the bias and variability in estimates obtained using the proposed optimal samplings and conventional monopolar sampling. Diffusion MRI of the liver was performed in 10 volunteers using 3 IVIM acquisitions conventional monopolar, optimized monopolar, and b-M
-optimized gradient waveforms (designed based on the optimal 2D sampling). IVIM parameter maps of diffusion coefficient, perfusion fraction, and blood velocity SD were obtained using nonlinear least squares fitting. Noise performance (SDs), stability (outlier percentage), and test-retest or scan-rescan repeatability (intraclass correlation coefficients) were evaluated and compared across acquisnt of IVIM quantitative biomarkers for liver diseases.Trichoderma reesei superoxide dismutase (TrSOD) is a well-characterized enzyme being stable between 30 and 90°C for 1 h with activity at pH between 2.6 and 9.0. This work aimed to clone, express, purify, and evaluate the protective effect antioxidant of this enzyme on skin cells when fused to transactivator of transcription (TAT) protein transduction domain of HIV-1 and abalone (Ab) peptides to allow cell penetration. TrSOD, TAT-TrSOD-Yfp (fused to yellow fluorescent protein), and Ab-TrSOD were expressed in E. coli and purified as soluble proteins. The cytotoxicity of the enzymes, at the concentrations of 1, 3, and 6 μmol/L, was evaluated for a period of 24 and 48 h of incubation, with no cytotoxic effect on 3T3 fibroblasts. The 3T3 cells were exposed to the oxidant agent tert-butyl hydroperoxide and evaluated for reactive oxygen species (ROS) generation, in the presence or not of the recombinant enzymes. TAT-TrSOD-Yfp was able to decrease the generation of ROS by 15% when used in the concentrations of 3 and 6 μmol/L in comparison to the control, but there was no difference in relation to the effect of TrSOD. Ab-TrSOD, when compared to TrSOD, promoted a decrease in the formation of ROS of 19% and 14% at the concentrations of 1 and 6 μmol/L, respectively, indicating that this recombinant form was more effective in reducing oxidative stress compared to SOD without the cell-penetrating peptide (CPP). Together, these results indicate that the fusion of SOD with these CPP increased the antioxidant capacity of fibroblasts, identified by the reduction in the generation of ROS. In addition, such molecules, in the concentrations initially used, were not toxic to the cells, opening perspectives for the development of products for antioxidant protection of the skin that may have therapeutic and cosmetic application.
Respiratory motion-compensated (MC) 3D cardiac fat-water imaging at 7T.
Free-breathing bipolar 3D triple-echo gradient-recalled-echo (GRE) data with radial phase-encoding (RPE) trajectory were acquired in 11 healthy volunteers (7M\4F, 21-35 years, mean 30 years) with a wide range of body mass index (BMI; 19.9-34.0 kg/m
) and volunteer tailored
B
1
+
shimming. The bipolar-corrected triple-echo GRE-RPE data were binned into different respiratory phases (self-navigation) and were used for the estimation of non-rigid motion vector fields (MF) and respiratory resolved (RR) maps of the main magnetic field deviations (ΔB
). RR ΔB
maps and MC ΔB
maps were compared to a reference respiratory phase to assess respiration-induced changes. CC-99677 price Subsequently, cardiac binned fat-water images were obtained using a model-based, respiratory motion-corrected image reconstruction.
The 3D cardiac fat-water imaging at 7T was successfully demonstrated. Local respiration-induced frequency shifts in MC ΔB
maps are small compared to the chemical shifts used in the multi-peak model. Compared to the reference exhale ΔB
map these changes are in the order of 10 Hz on average. Cardiac binned MC fat-water reconstruction reduced respiration induced blurring in the fat-water images, and flow artifacts are reduced in the end-diastolic fat-water separated images.
This work demonstrates the feasibility of 3D fat-water imaging at UHF for the entire human heart despite spatial and temporal
B
1
+
and B
variations, as well as respiratory and cardiac motion.
This work demonstrates the feasibility of 3D fat-water imaging at UHF for the entire human heart despite spatial and temporal B 1 + and B0 variations, as well as respiratory and cardiac motion.
This paper aims to highlight the attributes of engagement and urgency to act to control diabetes demonstrated by open-source artificial pancreas system users with the view that increased user involvement in research and practice can capitalize on these self-management traits; and to outline the challenges of researching outcomes in the context of unlicensed therapies.
A group of technically minded people with type 1 diabetes have reverse-engineered commercially available diabetes devices to help them achieve the diabetes outcomes they desire. Although studies have reported improved biomedical outcomes with these artificial pancreas systems, there are only a few studies examining patient-reported outcomes.
The investigation of patient-reported outcomes for open-source artificial pancreas system users has been hampered by the rapid advances in the technology, the lack of randomized controlled trials and the ethical challenges of researching unregulated technologies. There is an on-going debate about the most appropriate types of measures to evaluate patient-related outcomes.
The early adopters of open-source artificial pancreas systems exhibit many of the characteristics that predict optimal diabetes outcomes through engagement and urgency regarding self-management. These qualities should be harnessed to improve research in this and other areas of diabetes management.
The early adopters of open-source artificial pancreas systems exhibit many of the characteristics that predict optimal diabetes outcomes through engagement and urgency regarding self-management. These qualities should be harnessed to improve research in this and other areas of diabetes management.
Increasing suicide rates across the United States are disproportionate among populations most impacted by mass incarceration. We sought to determine if incarceration is associated with risk of suicide and firearm suicide after release from prison.
Using a population-based Washington cohort from Department of Corrections and vital statistics administrative records 1990-2017, individuals were compared to the sex-, age-, and race-matched population of Washington using Poisson regression. Among previously incarcerated individuals, we included incarceration history characteristics to calculate sub-hazard ratios using Cox proportional-hazards models.
Of 140,281 individuals released from prison, 484 died by suicide. Suicide risk was 62% higher among previously incarcerated individuals compared with the general population (RR 1.62; 95% CI 1.46-1.79). Suicide risk was higher among individuals convicted of firearm-involved crimes (RR 2.27; 95% CI 1.79-2.89). Individuals released prior to age 18 had substantially higher risk of firearm suicide than those whose first release occurred between ages 18-24 (sHR 11.
