bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutational screening through comprehensive bioinformatics analysis to detect novel germline mutations in the APC gene in patients with familial adenomatous polyposis (FAP)
Authors: Ghadamyari Faranak , Heidari Mohammad Mehdi , Zeinali Sirous , Khatami Mehri , Merat Shahin , Bagherian Hamideh , Rejali Leili , Ghasemi Farzaneh 
Published: March 2021

AbstractBackgroundFamilial adenomatous polyposis (FAP) as a colon cancer predisposition syndrome is an autosomal‐dominant inherited condition and is diagnosed by the progress of hundreds or thousands of adenomatous colonic polyps in the colon. This study aims at the nature and effect of Adenomatous Polyposis Coli (APC) gene mutations in FAP tumorigenesis.MethodsThe genetic screening of 59 FAP Iranian patients in 10 families was performed by polymerase chain reactions and the direct sequencing of the entire coding exons of the APC gene. To do linkage haplotype analysis and multiplex PCR‐based microsatellite examination, six short tandem repeat loci were selected in this gene. To evaluate and predict the potentially deleterious effects, comprehensive bioinformatics pathogenicity assays were used.ResultsA total of 12 germline heterozygous and homozygous nucleotide variations were identified. They included two missense mutations, four nonsense mutations, which would lead to the truncated and nonfunctional protein products, four synonymous or silent variations, and two nucleotide deletions of 1 to 5 bp or frameshift mutations. In addition, three novel heterozygous nonsense mutations were found in exons 10, 14, and 15 of the gene. There was also p.Arg653Met as a novel heterozygote mutation in exon 14 of the gene.ConclusionsBioinformatics analysis and three‐dimensional structural modeling predicted that these missense and nonsense mutations generally are associated with the deleted or truncated domains of APC and have functional importance and mainly affected the APC protein. These findings may provide evidence for the progress of potential biomarkers and help to understand the role of the APC gene in FAP.
Nitazoxanide versus rifaximin in preventing the recurrence of hepatic encephalopathy: A randomized double‐blind controlled trial
Authors: Glal Khadija A. M. , Abd‐Elsalam Sherief M. , Mostafa Tarek M. 
Published: March 2021

AbstractBackground/PurposeHepatic encephalopathy (HE) is a neuropsychiatric complication of liver cirrhosis. HE is associated with poor survival and detrimental effects on quality of life (QOL). The drawbacks of the long‐term use of rifaximin in HE necessitates searching for alternative therapies. In this context, our study aimed at evaluating the safety and efficacy of nitazoxanide (NTZ) as compared to rifaximin (RFX) in preventing the recurrence of HE and assessing its impact on QOL.Patients and MethodsThis prospective, randomized, double‐blind controlled study included 60 patients who were randomly assigned to receive either rifaximin 550 mg twice daily (group 1; n = 30) or nitazoxanide 500 mg twice daily (group 2; n = 30) for 24 weeks. During the study period, the patients' neurological symptoms, mental status, and performance were monitored. The serum levels of HE triggers (ammonia, TNF‐α, and octopamine) were assessed. The patients' health‐related quality of life was also evaluated.ResultsSix months after treatment, patients on NTZ therapy showed a statistically significant improvement in CHESS score and mental status. NTZ provided 136 days of remission vs 67 days of remission for patients on RFX (P1 = .0001) and significant reduction in Child score (P1 = .018). Additionally, NTZ showed a statistically significant decrease in serum ammonia, TNF‐α, and octopamine levels as compared to rifaximin. Regarding QOL, NTZ group showed an improvement in total Chronic Liver Disease Questionnaire (CLDQ) score. Both groups experienced minor controllable side effects.ConclusionNitazoxanide may represent a suitable and safe alternative therapy to rifaximin in preventing the recurrence of hepatic encephalopathy.
Efficacy and safety of the second‐generation cryoballoon ablation for the treatment of persistent atrial fibrillation in elderly patients
Authors: Vermeersch Gaëlle , Abugattas Juan‐Pablo , Varnavas Varnavas , De Cocker Jeroen , Schwagten Bruno , Sieira Juan , de Asmundis Carlo , Chierchia Gian‐Battista , De Greef Yves 
Published: March 2021

AbstractBackgroundIt is expected that ablation procedures will be increasingly offered to a more aged population affected with persistent AF (persAF); however, the clinical outcomes of ablation in this specific population are not well described. We aimed to analyze the efficacy and safety of CB‐A in this group of patients compared with a younger cohort.Methods and resultsEighty‐three patients with (persAF) aged ≥75 years (group 1; mean age 78.2 ± 3.1 years) and 166 patients also affected with persAF aged <75 years (group 2; mean age 64.3 ± 6.6 years) were included in the study. The primary outcome was freedom from recurrent sustained (>30 seconds) atrial arrhythmias without anti‐arrhythmic medication after a blanking period of 3 months. At 2 years, clinical success was achieved in 108 out of 249 patients (43.4%). Median follow‐up was 24 months (IQR: 18.4‐25.5 months). Older patients suffered from more recurrences than those in the younger cohort ((53/83 patients, 63.9% vs 88/166 patients, 53.0%; P = .03). Thirty (12.0%) patients suffered a complication, but the incidence of complications was not different between both groups. The most frequent complication was transient phrenic nerve injury.ConclusionsThe global 2 years efficacy of CB‐A PVI in persAF is 43.4%. A lower success rate is achieved in the older patients (36.1%) compared to the younger age group (47.0%). However, the complication rate was not different between age groups.
Observed changes in air temperature and precipitation extremes over Brazil
Authors: Regoto Pedro , Dereczynski Claudine , Chou Sin Chan , Bazzanela Anna Carolina 
Published: March 2021

AbstractWe analyse seasonal and annual trends of extreme indices of air temperature and precipitation over Brazil during the period 1961–2018. The main goal is to investigate whether the climate is changing and if so, to explore if there is any marked seasonality in such changes. The daily observed datasets of maximum and minimum temperatures, and precipitation, are provided by the Brazilian National Institute of Meteorology and National Water Agency. We use the Sen Curvature and Mann‐Kendall statistical tests to compute the magnitudes and to evaluate the statistical significance of climate extremes trends, respectively. The results show that the warm extremes frequency of occurrence is increasing significantly while the opposite occurs for cold extremes, which reveals a very consistent and widespread warming over Brazil. The highest increases in warm extremes occur during austral spring and summer while for the cold extremes the greatest decreases are observed during austral winter. Unlike temperature, precipitation extremes show heterogeneous signals for most of the country. In Northeast Brazil, there are changes towards a drier climate, especially in summer and autumn. In the Southern region, the climate is becoming wetter, with a reduction in consecutive dry days, especially in spring. For the other regions, there is no strong clear change sign, but both positive and negative precipitation extreme trends, without statistical significance (mostly in Southeast Region).
A Bayesian approach to diffusional kurtosis imaging
Authors: Umezawa Eizou , Ishihara Daichi , Kato Ryoichi 
Published: March 2021

PurposeDiffusional kurtosis metrics show high performance for detecting pathological changes and are therefore expected to be disease biomarkers. Kurtosis maps, however, tend to be noisy. The maps’ visual quality is crucial for disease diagnosis, even when kurtosis is being used quantitatively. A Bayesian method was proposed to curtail the large statistical error inherent in kurtosis estimation while maintaining potential application to biomarkers.TheoryGaussian priors are determined from first‐step estimations implemented using the least‐square method (LSM). The likelihood‐function variance is determined from the residuals of the estimation. Although the proposed approach is similar to a regularized LSM, regularization parameters do not have to be artificially adjusted. An appropriate balance between denoising and preventing false shrinkages of metric dispersions is automatically achieved.MethodsMap qualities achieved using the conventional and proposed methods were compared. The receiver‐operating characteristic analysis was performed for glioma‐grade differentiation using simulated low‐ and high‐grade glioma DWI datasets. Noninferiority of the proposed method was tested for areas under the curves (AUCs).ResultsThe noisier the conventional maps, the better the proposed Bayesian method improved them. Noninferiority of the proposed method was confirmed by AUC tests for all kurtosis‐related metrics. Superiority of the proposed method was also established for several metrics.ConclusionsThe proposed approach improved noisy kurtosis maps while maintaining their performances as biomarkers without increasing data acquisition requirements or arbitrarily choosing LSM regularization parameters. This approach may enable the use of higher‐order terms in diffusional kurtosis imaging (DKI) fitting functions by suppressing overfitting, thereby improving the DKI‐estimation accuracy.
Synchrotron X‐ray micro‐CT as a validation dataset for diffusion MRI in whole mouse brain
Authors: Trinkle Scott , Foxley Sean , Kasthuri Narayanan , La Rivière Patrick 
Published: March 2021

PurposeTo introduce synchrotron X‐ray microcomputed tomography (microCT) and demonstrate its use as a natively isotropic, nondestructive, 3D validation modality for diffusion MRI in whole, fixed mouse brain.MethodsPostmortem diffusion MRI and microCT data were acquired of the same whole mouse brain. Diffusion data were processed using constrained spherical deconvolution. Synchrotron data were acquired at an isotropic voxel size of 1.17 μm. Structure tensor analysis was used to calculate fiber orientation distribution functions from the microCT data. A pipeline was developed to spatially register the 2 datasets in order to perform qualitative comparisons of fiber geometries represented by fiber orientation distribution functions. Fiber orientations from both modalities were used to perform whole‐brain deterministic tractography to demonstrate validation of long‐range white matter pathways.ResultsFiber orientation distribution functions were able to be extracted throughout the entire microCT dataset, with spatial registration to diffusion MRI simplified due to the whole brain extent of the microCT data. Fiber orientations and tract pathways showed good agreement between modalities.ConclusionSynchrotron microCT is a potentially valuable new tool for future multi‐scale diffusion MRI validation studies, providing comparable value to optical histology validation methods while addressing some key limitations in data acquisition and ease of processing.
Analysis and mitigation of noise in simultaneous transmission and reception in MRI
Authors: Tasdelen Bilal , Sadeghi‐Tarakameh Alireza , Yilmaz Ugur , Atalar Ergin 
Published: March 2021

PurposeIn simultaneous transmission and reception (STAR) MRI, along with the coupling of the excitation pulse to the received signal, noise, and undesired distortions (spurs) coming from the transmit chain also leak into the acquired signal and degrade image quality. Here, properties of this coupled noise and its relationship with the transmit amplifier gain, transmit chain noise density, isolation performance, and imaging bandwidth are analyzed. It is demonstrated that by utilizing a recently proposed STAR technique, the transmit noise can be reduced. The importance of achieving high isolation and careful selection of the corresponding parameters are demonstrated.Theory and MethodsA cancellation algorithm, together with a vector modulator, is used for transmit‐receive isolation. The scanner is modeled as a pipeline of blocks to demonstrate the noise contribution from each block. With higher isolation, coupled transmit noise can be reduced to the point that the dominant noise source becomes acquisition noise, as in the case for pulsed MRI. Amplifiers with different gain and noise properties are used in the experiments to verify the derived noise‐transmit parameter relation.ResultsWith the proposed technique, more than 80 dB isolation in the analog domain is achieved. The leakage noise and the spurs coupled from the transmit chain, are reduced. It is shown that the transmit gain plays the most critical role in determining sufficient isolation, whereas the amplifier noise figure does not contribute as much.ConclusionThe transmit noise and the spurs in STAR imaging are analyzed and mitigated by using a vector modulator.
Incomplete inverse matrices
Authors: Filelis‐Papadopoulos Christos K. 
Published: March 2021

AbstractThe solution of large sparse linear systems is required in many scientific fields such as computational fluid dynamics, computational electromagnetism, computational finance, etc. The computation of the solution of these systems is performed with preconditioned iterative methods, which rely on effective preconditioning schemes. A new class of approximate inverses is proposed, namely incomplete inverse matrices, which are computed using a recursive Schur complement‐based approach. This class of approximate inverses is based on a priori knowledge of a sparsity pattern. In order to have finer control over the density of the proposed approximate inverse, especially in the case of three‐dimensional problems, on‐the‐fly filtration is used, resulting in substantial reduction in the number of nonzero elements. Implementation details and analysis for computing the proposed scheme are given. Numerical results depicting the effectiveness and applicability of the proposed scheme are also provided.
Inhibition of guanosine monophosphate synthetase (GMPS) blocks glutamine metabolism and prostate cancer growth
Authors: Wang Qian , Guan Yi Fang , Hancock Sarah E , Wahi Kanu , van Geldermalsen Michelle , Zhang Blake K , Pang Angel , Nagarajah Rajini , Mak Blossom , Freidman Natasha , Horvath Lisa G , Turner Nigel , Holst Jeff 
Published: March 2021

AbstractGlutamine is a critical nutrient in cancer; however, its contribution to purine metabolism in prostate cancer has not previously been determined. Guanosine monophosphate synthetase (GMPS) acts in the de novo purine biosynthesis pathway, utilizing a glutamine amide to synthesize the guanine nucleotide. This study demonstrates that GMPS mRNA expression correlates with Gleason score in prostate cancer samples, while high GMPS expression was associated with decreased rates of overall and disease/progression‐free survival. Pharmacological inhibition or knockdown of GMPS significantly decreased cell growth in both LNCaP and PC‐3 prostate cancer cells. We utilized [15N‐(amide)]glutamine and [U‐13C5]glutamine metabolomics to dissect the pathways involved and despite similar growth inhibition by GMPS knockdown, we show unique metabolic effects across each cell line. Using a PC‐3 xenograft mouse model, tumor growth was also significantly decreased after GMPS knockdown, highlighting the importance of glutamine metabolism and providing support for GMPS as a therapeutic target in prostate cancer. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Eco‐friendly polymer composites: A review of suitable methods for waste management
Authors: Cabrera Flávio C. 
Published: March 2021

AbstractThe amount of residues generated by agriculture, industrial, or urban activities continuously increases and, consequently, demands several methods for their correct management. The incorrect disposal can cause, in specific cases, environmental contamination by heavy metals or leaching as well as promote the spread of diseases as insect proliferation. Commonly, landfilling, incinerating, composting, or energy/fuel generation can control the disposal or reuse of residues. Among the methods for the reuse of wastes, the incorporation of residues as fillers in polymer composites has emerged as a distinct field. Some composites can potentially mitigate leaching compounds or improve mechanical, thermal, and acoustic properties. However, these improvements are a challenge to promote the use of waste fillers. Thus, this study aims to provide a state of view regarding a variety of wastes used as fillers in polymer composites and different methods to reach mechanical reinforcement as well as improve thermal conductivity and acoustic attenuation for future researches.
High‐performance and cost‐effective melt blended poly(ether ether ketone)/expanded graphite composites for mass production of antistatic materials
Authors: Mokhtari Mozaffar , Archer Edward , Bloomfield Noel , Harkin‐Jones Eileen , McIlhagger Alistair 
Published: March 2021

AbstractIn this study unfunctionalized expanded graphite (EG) was incorporated into poly(ether ether ketone) (PEEK) using twin‐screw extrusion and injection moulding to manufacture cost‐effective PEEK/EG composites for mass production of high‐performance antistatic materials. Direct current electrical conductivity, morphology, rheological and thermal properties of the composites were investigated. At an EG loading of 5 vol%, the electrical conductivity exhibited an abrupt increase to 1.45 × 10−5 S m−1 which was in the required range of electrical conductivity of antistatic materials. The frequency dependence of the storage modulus of the melt containing 2 vol% EG decreased significantly at low frequencies. Viscosity did not increase much with the addition of EG in comparison with other nanofillers such as carbon nanotubes. The crystallinity of PEEK increased to 41.11% from 35.87% upon addition of 3 vol% EG. EG improved the thermal stability of PEEK by an increase in the initiation temperature of its decomposition steps. © 2021 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry.
Finite‐time fault‐tolerant output feedback attitude control of spacecraft formation with guaranteed performance
Authors: Gao Han , Xia Yuanqing , Zhang Jinhui , Cui Bing 
Published: March 2021

AbstractThis article examines the problem of finite‐time fault‐tolerant output feedback attitude control for spacecraft formation system with guaranteed performance, in the presence of uncertainties, external disturbances, actuator faults, and input saturation. First, a neural network (NN) based finite‐time observer is established for follower spacecraft to observe its angular velocity, where the NN is utilized to approximate the unknown uncertainties. Furthermore, based on the information from the angular velocity observer, backstepping procedure, and barrier Lyapunov function technique, a distributed finite‐time controller with only attitude measurement is proposed. Unlike the existing finite‐time control scheme, the tracking errors keep inside their predefined feasible regions with guaranteed transient and steady‐state performance. A theoretical proof shows that the finite‐time stability of the closed‐loop system can be achieved. Finally, numerical simulation results are presented to illustrate the effectiveness and fine performance of the proposed finite‐time observer and controller for the attitude control system.
Biologically Active Quinoline‐Hydrazone Conjugates as Potential Trypanosoma cruzi DHFR‐TS Inhibitors: Docking, Molecular Dynamics, MM/PBSA and Drug‐Likeness Studies
Authors: Yepes Andrés F. , Quintero‐Saumeth Jorge , Cardona‐Galeano Wilson 
Published: March 2021

AbstractChagas disease, is a chronic parasitic infection caused by protozoan parasites belonging to the genus Trypanosoma. New therapies for Chagas infections are urgently needed and represent a major challenge in medicinal chemistry. As part of these efforts, we recently designed and synthesized a series of molecular hybrids bearing quinoline and hydrazones moieties, with some of them displaying higher anti‐trypanosomal activities than benznidazole. Thus, the current work is focused on proposing a plausible action mechanism by which the most active compounds inhibited T. cruzi growth based on multilevel computational approaches. Docking showed that for the best binders there was a marked preference for binding to dihydrofolate reductase (DHFR) over cruzipain (around −9.0 kcal/mol). MD simulations not only validate the reliability of docking predictions, but showed that the ligand‐receptor complex was stable during the extended 50 ns simulations inside the active site (RMSD value of 1.96±0.34 Å). Furthermore, MM/PBSA studies also affirm the docking results. The MM/PBSA method revealed that most of the residues involved in the binding event are hydrophobic in nature, which are in accordance with those aminoacids essential in the DHFR function. Satisfactory pharmacokinetics profiles were also estimated for the top‐three active compounds. Finally, the results suggested that the active hybrids might act by inhibiting DHFR activity within T. cruzi, making them a privileged scaffold that can be used in future anti‐Chagas drug development.
A Novel Perovskite Electron–Ion Conductive Coating to Simultaneously Enhance Cycling Stability and Rate Capability of Li1.2Ni0.13Co0.13Mn0.54O2 Cathode Material for Lithium‐Ion Batteries
Authors: Gao Mingxi , Yan Chenhui , Shao Qinong , Chen Jian , Zhang Chenyang , Chen Gairong , Jiang Yinzhu , Zhu Tiejun , Sun Wenping , Liu Yongfeng , Gao Mingxia , Pan Hongge 
Published: March 2021

AbstractPoor cycling stability and rate capability are two key issues needing to be solved for Li‐ and Mn‐rich oxide cathode material for lithium‐ion batteries (LIBs). Herein, a novel perovskite electron–ion mixed conductor Nd0.6Sr0.4CoO3 (NSCO) is used as the coating layer on Li1.2Ni0.13Co0.13Mn0.54O2 (LNCMO) to simultaneously enhance its cycling stability and rate capability. By coating 3 wt% NSCO, LNCMO–3NSCO exhibits an optimal cycling performance with a capacity retention of 99% at 0.1C (1C = 200 mA g−1) after 60 cycles, 91% at 1C after 300 cycles, and 54% at 20C after 1000 cycles, much better than 78%, 63%, and 3% of LNCMO, respectively. Even at a high charge and discharge rate of 50C, LNCMO–3NSCO exhibits a discharge capacity of 53 mAh g−1 and a mid‐point discharge voltage of 2.88 V, much higher than those of LNCMO (24 mA h g−1 and 2.40 V, respectively). Benefiting from the high electronic conductivity (1.46 S cm−1) and ionic conductivity (1.48 × 10−7 S cm−1), NSCO coating not only suppresses transition metals dissolution and structure transformation, but also significantly enhances electronic conductivity and Li+ diffusion coefficient of LNCMO by an order of magnitude.