bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bone regeneration with bovine bone impairs orthodontic tooth movement despite proper osseous wound healing in a novel mouse model
Authors: Klein Yehuda , Fleissig Omer , Stabholz Ayala , Chaushu Stella , Polak David 
Published: July 2018

AbstractBackgroundThe aim of this study was to investigate the biological mechanisms underlying alveolar bone regeneration (ABR) and orthodontic tooth movement into bovine bone (BB) regenerated sites.MethodsTwo mouse models were established in C57BL/6 mice. The ABR model was based on osseous defects filled with BB. The orthodontic tooth movement‐ABR model was used to move a molar into the regenerated site. Osseous morphometric analysis and tooth movement distance were evaluated with micro‐CT. Histologic characteristics and osteoclast (OCS) accumulation were evaluated by hematoxylin and eosin and tartrate‐resistant acid phosphatase staining (TRAP). Expression and location of the receptor activator of nuclear factor‐kappa B (RANKL) and of osteoprotegerin (OPG) were evaluated by immunofluorescent staining.ResultsBone healing peaked at 4 weeks. The distance of the orthodontic tooth movement into the bovine bone was significantly reduced versus that of the nonbovine bone controls. BB particles accumulated along the root's pressure side during orthodontic treatment. Despite the osteoclasts’ presence adjacent to the BB particles, no BB resorption was observed. Increased RANKL expression was seen at the orthodontic tooth movement pressure zone, without any change in OPG expression.ConclusionThe two novel mouse models show that the lack of resorption of BB xenografts renders them inadequate for proper orthodontic tooth movement at a later stage.
Characteristics of starch from different bean genotypes and its effect on biodegradable films
Authors: Vanier Nathan Levien , de Oliveira Jean Paulo , Bruni Graziella Pinheiro , El Halal Shanise Lisie Mello , Villanova Franciene Almeida , Zavareze Elessandra da Rosa , Dias Alvaro Renato Guerra , Bassinello Priscila Zaczuk 
Published: July 2018

AbstractBACKGROUNDStarches from four common bean genotypes were characterized and used in the production of biodegradable films. Starches were characterized by their swelling power, solubility, amylose content, granule morphology, relative crystallinity, thermal and pasting properties, and susceptibility to α‐amylase hydrolysis. Films were characterized according to their morphology, mechanical and water vapor barrier properties, whiteness and opacity.RESULTDepending on the common bean genotype, a great variation on starch properties was found, which, in turn, clearly impacted on the characteristics of the starch‐based films. Starches from BRS Pitanga and BRS Pérola genotypes exhibited the highest amylose content and the lowest swelling capabilities. Bean starch from the IPR Uirapuru genotype presented granules with an irregular surface and shape. Starches from IPR Uirapuru and BRS Estilo genotypes provided well‐structured biodegradable films, without the occurrence of fissures or cracks. Moreover, starch films containing starch from BRS Estilo genotype exhibited the highest flexibility, permeability and solubility.CONCLUSIONThe morphological, mechanical and water vapor barrier properties of films elaborated with common bean starch vary greatly as a function of the bean genotype used for starch production. © 2018 Society of Chemical Industry
Whitepaper: Practical challenges for researchers in data sharing: Review
Authors: Kessler Rachel 
Published: July 2018

Key points
Springer Nature's white paper seeks to determine the main obstacles for data sharing and looks at how discipline, region, and seniority impact data sharing.
The greatest issue around data sharing is organizing the data in a useful way.
The amount of data sharing varies widely within the sciences, with biology researchers sharing the most and physical sciences sharing the least.
Asian researchers share their data the most while Australasians share the least.
The white paper underestimates the importance of attitudes when assessing the obstacles.
The report does not include a statistical analysis to confirm whether the observed trends were significant.
1.7 micron optical coherence tomography for vaginal tissue characterization in vivo
Authors: Li Yan , Sudol Neha T. , Miao Yusi , Jing Joseph C. , Zhu Jiang , Lane Felicia , Chen Zhongping 
Published: July 2018

ObjectivesOptical coherence tomography (OCT) can noninvasively visualize in vivo tissue microstructure with high spatial resolution that approaches the histologic level. Currently, OCT studies in gynecology are few and limited to a conventional 1.3 μm center wavelength swept light source which provides high spatial resolution but limited penetration depth. Here, we present a novel endoscopic OCT system with improved penetration depth and high resolution.MethodsA novel endoscopic OCT system was developed based on a 1.7 µm swept source laser, which is capable of deeper tissue penetration due to its longer wavelength. To evaluate the performance of system, we imaged the human vaginas in vivo with both conventional 1.3 and 1.7 μm endoscopic OCT systems.ResultsWith the 1.7 μm endoscopic OCT system, imaging depth was improved by more than 25%, allowing better visualization of the lamina propria and clear contrast of the epithelial layer from the surrounding tissues.ConclusionThe significantly improved performance of the novel 1.7 μm OCT imaging system demonstrates its potential use as a minimally‐invasive monitoring tool of vaginal health in gynecologic practice. Lasers Surg. Med. 51:120–126, 2019. © 2018 Wiley Periodicals, Inc.
Advances in digital and physical anthropomorphic breast phantoms for x‐ray imaging
Authors: Glick Stephen J. , Ikejimba Lynda C. 
Published: July 2018

PurposeWith the advent of three‐dimensional (3D) breast imaging modalities such as digital breast tomosynthesis (DBT) and dedicated breast CT (bCT), research into new anthropomorphic breast phantoms has accelerated. These breast phantoms are important for the optimization of new breast imaging systems, assessing new regulatory submissions to prove safety and effectiveness, and for developing new approaches to acceptance and constancy testing of 3D breast imaging systems. This paper provides a review of current research investigating both digital and physical breast phantom development for use in x‐ray based imaging.MethodsTwo approaches for designing anthropomorphic, digital breast phantoms are discussed, procedural model‐based phantom generation, where breast features are expressed using mathematical models, and patient‐based generation, where breast structures from tissue specimens or patient‐based breast MR or CT volumes are segmented. Following this discussion, a review of physical anthropomorphic phantoms is given, with emphasis on the advantages and disadvantages present with each approach.ConclusionsThis paper provides a summary of the state‐of‐the‐art in anthropomorphic breast phantom development for x‐ray breast imaging. The primary advantage of model‐based digital phantoms is that an unlimited number of phantoms with varying size, shape, and density can be generated. Current research on model‐based breast phantoms is producing more and more realistic breast models; however, they probably are not yet able to pass the so‐called “fool the radiologist” visualization test. Empirical patient‐based breast phantoms are typically based on clinical breast CT data and look more realistic. However, clinical breast CT images have limited spatial resolution and thus do not always portray the finer details in the breast. A number of innovative solutions have been proposed for fabricating physical anthropomorphic breast phantoms based on digital phantom models; however, a number of challenges remain, including realistic modeling of x‐ray attenuation properties and accurately representing high‐frequency structures within breast.
Comparison of prospective head motion correction with NMR field probes and an optical tracking system
Authors: Eschelbach Martin , Aghaeifar Ali , Bause Jonas , Handwerker Jonas , Anders Jens , Engel Eva‐Maria , Thielscher Axel , Scheffler Klaus 
Published: July 2018

PurposeThe aim of this study was to compare prospective head motion correction and motion tracking abilities of two tracking systems: Active NMR field probes and a Moiré phase tracking camera system using an optical marker.MethodsBoth tracking systems were used simultaneously on human subjects. The prospective head motion correction was compared in an MP2RAGE and a gradient echo sequence. In addition, the motion tracking trajectories for three subjects were compared against each other and their correlation and deviations were analyzed.ResultsWith both tracking systems motion artifacts were visibly reduced. The precision of the field probe system was on the order of 50 µm for translations and 0.03° for rotations while the camera's was approximately 5 µm and 0.007°. The comparison of the measured trajectories showed close correlation and an average absolute deviation below 500 µm and 0.5°.ConclusionThis study presents the first in vivo comparison between NMR field probes and Moiré phase tracking. For the gradient echo images, the field probes had a similar motion correction performance as the optical tracking system. For the MP2RAGE measurement, however, the camera yielded better results. Still, both tracking systems substantially decreased image artifacts in the presence of subject motion. Thus, the motion tracking modality should be chosen according to the specific requirements of the experiment while considering the desired image resolution, refresh rate, and head coil constraints.
Five‐minute whole‐heart coronary MRA with sub‐millimeter isotropic resolution, 100% respiratory scan efficiency, and 3D‐PROST reconstruction
Authors: Bustin Aurélien , Ginami Giulia , Cruz Gastão , Correia Teresa , Ismail Tevfik F. , Rashid Imran , Neji Radhouene , Botnar René M. , Prieto Claudia 
Published: July 2018

PurposeTo enable whole‐heart 3D coronary magnetic resonance angiography (CMRA) with isotropic sub‐millimeter resolution in a clinically feasible scan time by combining respiratory motion correction with highly accelerated variable density sampling in concert with a novel 3D patch‐based undersampled reconstruction (3D‐PROST).MethodsAn undersampled variable density spiral‐like Cartesian trajectory was combined with 2D image‐based navigators to achieve 100% respiratory efficiency and predictable scan time. 3D‐PROST reconstruction integrates structural information from 3D patch neighborhoods through sparse representation, thereby exploiting the redundancy of the 3D anatomy of the coronary arteries in an efficient low‐rank formulation. The proposed framework was evaluated in a static resolution phantom and in 10 healthy subjects with isotropic resolutions of 1.2 mm3 and 0.9 mm3 and undersampling factors of ×5 and ×9. 3D‐PROST was compared against fully sampled (1.2 mm3 only), conventional parallel imaging, and compressed sensing reconstructions.ResultsPhantom and in vivo (1.2 mm3) reconstructions were in excellent agreement with the reference fully sampled image. In vivo average acquisition times (min:s) were 7:57 ± 1:18 (×5) and 4:35 ± 0:44 (×9) for 0.9 mm3 resolution. Sub‐millimeter 3D‐PROST resulted in excellent depiction of the left and right coronary arteries including small branch vessels, leading to further improvements in vessel sharpness and visible vessel length in comparison with conventional reconstruction techniques. Image quality rated by 2 experts demonstrated that 3D‐PROST provides good image quality and is robust even at high acceleration factors.ConclusionThe proposed approach enables free‐breathing whole‐heart 3D CMRA with isotropic sub‐millimeter resolution in <5 min and achieves improved coronary artery visualization in a short and predictable scan time.
Rapid dynamic contrast‐enhanced MRI for small animals at 7T using 3D ultra‐short echo time and golden‐angle radial sparse parallel MRI
Authors: Zhang Jin , Feng Li , Otazo Ricardo , Kim Sungheon Gene 
Published: July 2018

PurposeTo develop a rapid dynamic contrast‐enhanced MRI method with high spatial and temporal resolution for small‐animal imaging at 7 Tesla.MethodsAn ultra‐short echo time (UTE) pulse sequence using a 3D golden‐angle radial sampling was implemented to achieve isotropic spatial resolution with flexible temporal resolution. Continuously acquired radial spokes were grouped into subsets for image reconstruction using a multicoil compressed sensing approach (Golden‐angle RAdial Sparse Parallel; GRASP). The proposed 3D‐UTE‐GRASP method with high temporal and spatial resolutions was tested using 7 mice with GL261 intracranial glioma models.ResultsIterative reconstruction with different temporal resolutions and regularization factors λ showed that, in all cases, the cost function decreased to less than 2.5% of its starting value within 20 iterations. The difference between the time‐intensity curves of 3D‐UTE‐GRASP and nonuniform fast Fourier transform (NUFFT) images was minimal when λ was 1% of the maximum signal intensity of the initial NUFFT images. The 3D isotropic images were used to generate pharmacokinetic parameter maps to show the detailed images of the tumor characteristics in 3D and also to show longitudinal changes during tumor growth.ConclusionThis feasibility study demonstrated that the proposed 3D‐UTE‐GRASP method can be used for effective measurement of the 3D spatial heterogeneity of tumor pharmacokinetic parameters.
Toward more reliable measurements of NOE effects in CEST spectra at around −1.6 ppm (NOE (−1.6)) in rat brain
Authors: Zu Zhongliang 
Published: July 2018

PurposeRecently, a new relayed nuclear Overhauser enhancement (NOE) saturation transfer effect at around −1.6 parts per million, termed NOE(−1.6), and its potential applications in tumor and stroke were reported by several institutes. However, there is a concern of the reproducibility of NOE(−1.6) measurements because it is not reported by many other publications. This paper aims to study the influence of typically overlooked experimental settings on the NOE(−1.6) signal and to build a framework for more reliable measurements of NOE(−1.6) at 9.4T.MethodsZ‐spectra were obtained in rat brains. A fitting approach was performed to quantify all known saturation transfer effects except NOE(−1.6). Residual signals were obtained by removing these confounding effects from Z‐spectra and were then used to quantify NOE(−1.6). Multislice imaging was performed to study the NOE(−1.6) dependence on brain regions. The influences of euthanasia, anesthesia, breathing gases, and RF irradiation power were also evaluated.ResultsResults demonstrate that the NOE(−1.6) signal contributions are often not clearly observable in raw Z‐spectra at relatively high irradiation powers due to, for example, the direct water saturation effect, but they can be visualized after removing other nonspecific effects. In addition, the NOE(−1.6) effect depends on brain region, decreases postmortem, shifts after long‐duration anesthesia, and may be enhanced by increasing O2 and N2O breathing air concentrations.ConclusionBecause the NOE(−1.6) effect is more susceptible to the direct water saturation effect and more sensitive to physiological conditions than are other CEST effects, incorporating known sensitivities into the experimental design and data analysis is necessary to ensure more reliable NOE(−1.6) results.
Determination of multipool contributions to endogenous amide proton transfer effects in global ischemia with high spectral resolution in vivo chemical exchange saturation transfer MRI
Authors: Zhou Iris Yuwen , Lu Dongshuang , Ji Yang , Wu Limin , Wang Enfeng , Cheung Jerry S. , Zhang Xiao‐An , Sun Phillip Zhe 
Published: July 2018

PurposeChemical exchange saturation transfer (CEST) MRI has been used for quantitative assessment of dilute metabolites and/or pH in disorders such as acute stroke and tumor. However, routine asymmetry analysis (MTRasym) may be confounded by concomitant effects such as semisolid macromolecular magnetization transfer (MT) and nuclear Overhauser enhancement. Resolving multiple contributions is essential for elucidating the origins of in vivo CEST contrast.MethodsHere we used a newly proposed image downsampling expedited adaptive least‐squares fitting on densely sampled Z‐spectrum to quantify multipool contribution from water, nuclear Overhauser enhancement, MT, guanidinium, amine, and amide protons in adult male Wistar rats before and after global ischemia.ResultsOur results revealed the major contributors to in vivo T1‐normalized MTRasym (3.5 ppm) contrast between white and gray matter (WM/GM) in normal brain (−1.96%/second) are pH‐insensitive macromolecular MT (−0.89%/second) and nuclear Overhauser enhancement (−1.04%/second). Additionally, global ischemia resulted in significant changes of MTRasym, being −2.05%/second and −1.56%/second in WM and GM, which are dominated by changes in amide (−1.05%/second, −1.14%/second) and MT (−0.88%/second, −0.62%/second). Notably, the pH‐sensitive amine and amide effects account for nearly 60% and 80% of the MTRasym changes seen in WM and GM, respectively, after global ischemia, indicating that MTRasym is predominantly pH‐sensitive.ConclusionCombined amide and amine effects dominated the MTRasym changes after global ischemia, indicating that MTRasym is predominantly pH‐sensitive and suitable for detecting tissue acidosis following acute stroke.
Intricacies in three‐dimensional limit analysis of earth slopes
Authors: Park Dowon , Michalowski Radoslaw L. 
Published: July 2018

SummaryAnalyses of three‐dimensional slope failures can be elaborate because of the complexity owed to the geometry of the failure mechanism that needs to conform to an admissible kinematics of the slope collapse. This admissibility is imposed by the soil limit state condition, the normality plastic flow rule, and the boundary conditions. The kinematic approach of limit analysis is employed, and a rotational 3D slope failure is revisited. The study leads to the conclusion that some geometric constraints used in previous studies limit the range of admissible mechanisms resulting in overestimating stability factors. A set of results is presented that was obtained using an algorithm that allowed eliminating limitations present in previous studies. The largest improvements in the solutions were found for undrained failures of narrow slopes. For a 30° slope limited in width by the width‐to‐height ratio of 0.6, the stability factor calculated in previous studies overestimated the current calculations by nearly 39%. This overestimation is smaller for drained failures, and it drops significantly with an increase in the width of the failure mechanism.
Rheological determinants for simultaneous staging of hepatic fibrosis and inflammation in patients with chronic liver disease
Authors: Sinkus Ralph , Lambert Simon , Abd‐Elmoniem Khaled Z. , Morse Caryn , Heller Theo , Guenthner Christian , Ghanem Ahmed M. , Holm Sverre , Gharib Ahmed M. 
Published: July 2018

The purpose of this study is to investigate the use of fundamental rheological parameters as quantified by MR elastography (MRE) to measure liver fibrosis and inflammation simultaneously in humans.MRE was performed on 45 patients at 3 T using a vibration frequency of 56 Hz. Fibrosis and inflammation scores were obtained from liver biopsies. Biomechanical properties were quantified in terms of complex shear modulus G* as well as shear wave phase velocity c and shear wave attenuation α. A rheological fractional derivative order model was used to investigate the linear dependence of the free model parameters (dispersion slope y, intrinsic speed c0, and intrinsic relaxation time τ) on histopathology. Leave‐one‐out cross‐validation was then utilized to demonstrate the effectiveness of the model.The intrinsic speed c0 increases with hepatic fibrosis, while an increased relaxation time τ is reflective of more inflammation of the liver parenchyma. The dispersion slope y does not depend either on fibrosis or on inflammation. The proposed rheological model, given this specific parameterization, establishes the functional dependences of biomechanical parameters on histological fibrosis and inflammation. The leave‐one‐out cross‐validation demonstrates that the model allows identification, from the MRE measurements, of the histology scores when grouped into low−/high‐grade fibrosis and low−/high‐grade inflammation with significance levels of P = 0.0004 (fibrosis) and P = 0.035 (inflammation).The functional dependences of intrinsic speed and relaxation time on fibrosis and inflammation, respectively, shed new light onto the impact hepatic pathological changes on liver tissue biomechanics in humans. The dispersion slope y appears to represent a structural parameter of liver parenchyma not impacted by the severity of fibrosis/inflammation present in this patient cohort. This specific parametrization of the well‐established rheological fractional order model is valuable for the clinical assessment of both fibrosis and inflammation scores, going beyond the capability of the plain shear modulus measurement commonly used for MRE.
Multilevel heterogeneity of mitochondrial respiratory chain deficiency
Authors: Vincent Amy E , Picard Martin 
Published: July 2018

AbstractMitochondrial diseases are heterogeneous multisystem disorders that show a mosaic pattern of mitochondrial respiratory chain dysfunction. The mitochondrial DNA (mtDNA) mutation load is heterogeneous at multiple levels: across organs, between cells, and between subcellular compartments. Such heterogeneity poses a diagnostic challenge, but also provides a scientific opportunity to explore the biological mechanisms underlying the onset and progression of these disorders. A recent article in The Journal of Pathology described a novel histochemical technique – nitro blue tetrazolium exclusion assay (NBTx) ‐ to quantify mitochondrial cytochrome c oxidase (COX, or complex IV) deficiency. This technique is rapid, cost‐effective, and quantitative, and is more sensitive than previous histochemical methods. It can also be applied across model organisms and human tissues. The NBTx method should therefore be a useful diagnostic tool, and may catalyze research examining the cellular and subcellular mechanisms that drive the onset and progression of inherited and acquired mtDNA disorders. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.