Fernandezharrell3548

To evaluate the potency of potential helicase modulators, we developed an assay of helicase enzyme activity. Using a DNA or RNA biotin labelled oligonucleotide and after the addition of a recombinant helicase, the nucleic acid unwinds, causing the emission of luminescence, which is quantified with a particular antibody. In our assay, one of the DNA oligos was biotinylated, while the other was labelled with digoxygenin (DIG), both in their 5' termini. The biotin molecule immobilises the DNA duplex on a neutravidin-coated plate and the helicase activity is measured through the unwinding of DNA, due to ATP activation. The subsequent release of DIG-labelled oligos results in a luminescence signal measured with a chemiluminescence antibody. Our goal was to provide a high throughput screening method for potential helicase inhibitors. The method described in this paper has been demonstrated to be fast, easy and reproducible and doesn't use radiochemicals.Background Paraspinal musculature forms one of the largest muscle compartments of the human body, but evidence for regional variation of its composition and dependency on gender or body mass index (BMI) is scarce. Methods This study applied six-echo chemical shift encoding-based water-fat magnetic resonance imaging (MRI) at 3 Tesla in 76 subjects (24 males and 52 females, age 40.0±13.7 years, BMI 25.4±5.6 kg/m2) to evaluate the proton density fat fraction (PDFF) of psoas muscles and erector spinae muscles, with the latter being divided into three segments in relation to levels of spine anatomy (L3-L5, T12-L2, and T9-T11). Results For the psoas muscles and the erector spinae muscles (L3-L5), gender differences in PDFF values were observed (PDFF psoas muscles males 5.1%±3.4% vs. females 6.0%±2.2%, P=0.006; PDFF erector spinae muscles L3-L5 males 10.7%±7.6% vs. females 18.2%±6.8%, P less then 0.001). Furthermore, the PDFF of the erector spinae muscles (L3-L5) showed higher PDFF values when compared to the other segments (PDFF erector spinae muscles L3-L5 vs. T12-L2 P less then 0.001; PDFF erector spinae muscles L3-L5 vs. T9-T11 P less then 0.001) and showed to be independent of BMI, which was not the case for the other segments (T12-L2 or T9-T11) or the psoas muscles. When considering age and BMI as control variables, correlations of PDFF between segments of the erector spinae muscles remained significant for both genders. Conclusions This study explored regional variation of paraspinal muscle composition and dependency on gender and BMI, thus offering new insights into muscle physiology. The PDFF of the erector spinae muscles (L3-L5) was independent of BMI, suggesting that this level may be suited for representative paraspinal muscle segmentation and PDFF extraction as a biomarker for muscle alterations in the future. 2020 Quantitative Imaging in Medicine and Surgery. All rights reserved.Background This study aimed to investigate the associations between cardiac strain, cardiac torsion, ventricular volumes, and ventricular ejection fraction, with N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in Fontan patients who were age- and gender-matched with healthy control subjects. Adeninesulfate Methods Cardiovascular magnetic resonance (CMR) studies performed in 22 (15 male, 7 female) patients with single-ventricle physiology (all morphological left ventricles) palliated with Fontan and 17 (10 male, 7 female) age- and gender-matched healthy children volunteers were retrospectively analyzed. Serum NT-proBNP levels were obtained in Fontan subjects. Standard post-processing of CMR images included systemic ventricular end-diastolic and end-systolic volumes, stroke volume, cardiac mass, atrioventricular regurgitation, and ejection fraction. CMR tissue tracking (TT) software was used to quantify global longitudinal strain (GLS), global radial strain (GRS), and global circumferential strain (GCS) and torsiQuantitative Imaging in Medicine and Surgery. All rights reserved.Background The primary goal of many computer-assisted surgical systems like robotics for total knee arthroplasty (TKA) is to accurately execute a preoperative plan. To assess whether the preoperative plan was executed accurately in 3D, one option is to compare the planned and postoperative implant placement using a preoperative and postoperative CT scan of the patient's limb. This comparison requires a 3D-to-3D surface registration between the preoperative and postoperative 3D bone models and between the planned and postoperative 3D implants. Hence, the present study aimed at validating this measurement technique by determining (I) the anatomical regions that result in the lowest 6-degree of freedom (DoF) errors for 3D-to-3D surface registration of bone models, (II) the 6-DoF errors for 3D-to-3D surface registration of the implant models, and (III) the 6-DoF of the complete measurement technique. Methods Four different regions of the femur were tested to determine which one would result in the most accurate 3anslations and up to 0.6° in rotations in component placement are acceptable. 2020 Quantitative Imaging in Medicine and Surgery. All rights reserved.Background Apolipoprotein E (ApoE) ε 4 has been identified as the strongest genetic risk factor for Alzheimer's disease (AD). However, the importance of ApoE ε 4 on clinical and biological heterogeneity of AD is still to be determined, particularly at the prodromal stage. Here, we evaluate the association of ApoE ε 4 with clinical cognition and neuroimaging regions in mild cognitive impairment (MCI) participants based on the AT (N) system, which is increasingly essential for developing a precise assessment of AD. Methods We stratified 178 A+T+MCI participants (prodromal AD) into ApoE ε 4 (+) and ApoE ε 4 (-) according to ApoE genotype from the Alzheimer's Disease Neuroimaging Initiative (ADNI). We determined Aβ-positivity (A+) by the standardized uptake values ratios (SUVR) means of florbetapir-PET-AV45 (the cut-off value of 1.1) and fibrillar tau-positivity (T+) by cerebrospinal fluid (CSF) phosphorylated-tau at threonine 181 position (p-Tau) (cut-off value of 23 pg/mL). We evaluated the effect of ApoE ε 4 status on cognitive conditions and brain atrophy from structural magnetic resonance imaging (MRI) scans.