bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sub‐millimeter T1 mapping of rapidly relaxing compartments with gradient delay corrected spiral TAPIR and compressed sensing at 3T
Authors: Claeser Robert , Zimmermann Markus , Shah N. Jon 
Published: May 2019

PurposeThe TAPIR sequence is an accurate and efficient method for T1 mapping. It combines a slice‐interleaving Look‐Locker read‐out with an acquisition of multiple k‐space lines in 1 shot. Whereas the acquisition of multiple lines per excitation increases imaging speed, the corresponding increase in TR and TE is detrimental to the T1 fitting performance. This is especially problematic for substances exhibiting rapid T2* relaxation (e.g., myelin water).MethodsThe T1 fitting performance of TAPIR is enhanced by using an interleaved spiral read‐out with shorter TE and TR. Furthermore, an improvement to a method for fast gradient delay estimation is presented. Whereas previous methods assume the gradient delay to be stationary, the presented approach corrects the spiral k‐space trajectory by using a polynomial fit of the measured gradient delays.ResultsGradient delay artifacts are largely eliminated, requiring very little additional scanning time. The sampling efficiency of the spiral read‐out allows for a significant reduction of the acquisition time in comparison to Cartesian TAPIR. Spiral TAPIR enables the sampling of more slices and an accurate measurement of rapidly relaxing compartments. Over a wide T1 range (448–3115 ms), spiral TAPIR reduces the mean fitting error from −2.5% to −0.1%. Combining 50% undersampling with the shorter TR of spiral TAPIR, an increase in imaging speed by a factor of up to 3.3 was achieved.ConclusionUsing a spiral read‐out trajectory, the established TAPIR sequence enables measurement of rapidly relaxing T1 compartments, while improving T1 mapping performance and imaging speed.
Water removal in MR spectroscopic imaging with L2 regularization
Authors: Lin Liangjie , Považan Michal , Berrington Adam , Chen Zhong , Barker Peter B. 
Published: May 2019

PurposeAn L2‐regularization based postprocessing method is proposed and tested for removal of residual or unsuppressed water signals in proton MR spectroscopic imaging (MRSI) data recorded from the human brain at 3T.MethodsWater signals are removed by implementation of the L2 regularization using a synthesized water‐basis matrix that is orthogonal to metabolite signals of interest in the spectral dimension. Simulated spectra with variable water amplitude and in vivo brain MRSI datasets were used to demonstrate the proposed method. Results were compared with two commonly‐used postprocessing methods for removing water signals.ResultsThe L2 method yielded metabolite signals that were close to true values for the simulated spectra. Residual/unsuppressed water signals in human brain short‐ and long‐echo time MRSI datasets were efficiently removed by the proposed method allowing good quality metabolite maps to be reconstructed with minimized contamination from water signals. Significant differences of the creatine signal were observed between brain long‐echo time MRSI without and with water saturation, attributable to the previously described magnetization transfer effect.ConclusionsWith usage of a synthesized water matrix generated based on reasonable prior knowledge about water and metabolite resonances, the L2 method is shown to be an effective way to remove water signals from MRSI of the human brain.
Do Women Know Their Prepregnancy Weight?
Authors: Thomas Diana M. , Oken Emily , Rifas‐Shiman Sheryl L. , Téllez‐Rojo Martha , Just Allan , Svensson Katherine , Deierlein Andrea L , Chandler‐Laney Paula C. , Miller Richard C. , McNamara Christopher , Phelan Suzanne , Yoshitani Shaw , Butte Nancy F. , Redman Leanne M. 
Published: May 2019

ObjectivePrepregnancy weight may not always be known to women. A model was developed to estimate prepregnancy weight from measured pregnancy weight.MethodsThe model was developed and validated using participants from two studies (Project Viva, n = 301, model development; and Fit for Delivery [FFD], n = 401, model validation). Data from the third study (Programming Research in Obesity, Growth, Environment and Social Stressors [PROGRESS]), which included women from Mexico City, were used to demonstrate the utility of the newly developed model to objectively quantify prepregnancy weight.ResultsThe model developed from the Project Viva study validated well with low bias (R2 = 0.95; y = 1.02x − 0.69; bias = 0.68 kg; 95% CI: −4.86 to 6.21). Predictions in women from FFD demonstrated good agreement (R2 = 0.96; y = 0.96x + 4.35; bias = 1.60 kg; 95% CI: −4.40 to 7.54; error range = −11.25 kg to 14.73 kg). High deviations from model predictions were observed in the Programming Research in PROGRESS (R2 = 0.81; y = 0.89x + 9.61; bias = 2.83 kg; 95% CI: −7.70 to 12.31; error range = −39.17 kg to 25.73 kg). The model was programmed into software (https://www.pbrc.edu/research-and-faculty/calculators/prepregnancy/).ConclusionsThe developed model provides an alternative to determine prepregnancy weight in populations receiving routine health care that may not have accurate knowledge of prepregnancy weight. The software can identify misreporting and classification into incorrect gestational weight gain categories.
Feasibility and efficacy of a novel technology‐based approach to harness social networks for weight loss: the NETworks pilot randomized controlled trial
Authors: Monroe C. M. , Geraci M. , Larsen C. A. , West D. S. 
Published: May 2019

SummaryObjectiveHarnessing social support from existing social ties represents a key weight control practice. This trial evaluated an intervention that provided health‐promoting technologies for leveraging the influence of existing social ties.MethodsVolunteers (N = 36) with a body mass index between 25 and 55 kg m−2 were randomized to a 16‐week, in‐person, technology‐supported behavioural weight‐loss treatment (standard behavioural treatment) or the same programme supplemented by providing self‐selected members of participants' social networks with a digital body‐weight scale and Fitbit Zip physical activity tracker (ENHANCED).ResultsAverage weight losses from baseline to 16 weeks did not significantly differ between groups (standard behavioural treatment, 5.30%, SD =3.93%; ENHANCED, 5.96%, SD = 5.19%, p = 0.63). By the 1‐year follow‐up, standard behavioural treatment had lost 5.63%, SD = 8.14% of baseline weight versus 4.73%, SD = 9.43% for ENHANCED (p = 0.82). ENHANCED reported self‐weighing on more days than did standard behavioural treatment (p = 0.03). Most participants reported high programme satisfaction. Similar improvements were observed in perceived social support for diet and exercise from baseline to 16 weeks in both groups (ps < 0.05) but regressed by 1 year (ps < 0.01).ConclusionAlthough feasible to implement, this technology‐based, social support approach failed to enhance outcomes of a face‐to‐face, group‐based behavioural weight‐loss treatment.
Regional practice norms for the care of childhood cancer survivors at risk for cardiomyopathy: A Delphi study
Authors: Kenney Lisa B. , Ames Bethany , Margossian Renee , Moss Kerry , Michaud Alexis L. , Williams David N. , Nohria Anju 
Published: May 2019

AbstractBackgroundTreatment‐associated cardiomyopathy is a leading cause of morbidity and mortality for childhood cancer survivors (CCS). As evidence is not available to guide the management of CCS at risk for cardiomyopathy, we aim to describe the collective opinion of regional experts for the care of these patients using a consensus‐based Delphi methodology.ProcedureNineteen physicians from the New England region who care for CCS treated with cardiotoxic therapy (anthracyclines, thoracic radiation) participated in a Delphi panel querying their management approach, using three rounds of anonymous questionnaires formatted as five clinical scenarios. Consensus ≥ 89% agreement.ResultsThe response rate was 100% for the first round and 95% for subsequent rounds. Panelists reached consensus on screening asymptomatic CCS with serial echocardiograms (94%) and electrocardiograms (89%), with some disagreement on frequency during pregnancy (83%). All panelists agreed with exercise promotion, with no restrictions on weight training. Consensus was reached on indications for referrals; cardiology for asymptomatic left ventricular dysfunction (ALVD) (100%) and maternal–fetal medicine for pregnancy (94%). In the scenario of ALVD, there was disagreement on the benefit of additional cardiac testing (50% cardiologists recommended cardiac MRI), and although all panelists endorsed treating with angiotension‐converting enzyme (ACE) inhibitors, most adult cardiologists (75%) also recommended therapy with beta blockers, compared with none of the pediatric cardiologists or primary‐care physicians.ConclusionsDespite a lack of evidence to guide the management of CCS at risk for cardiomyopathy, a panel of regional physicians reached consensus on managing most clinical scenarios. A controversial area requiring further study is the medical management of ALVD.
Selective dispersion of silver nanowires in epoxy/polyetherimide binary composites with enhanced electrical conductivity: a study of curing kinetics and morphology
Authors: Liu Yuanyuan , Yang Xiaodan , Yue Lansong , Li Weizhen , Gan Wenjun , Chen Kaimin 
Published: May 2019

AbstractThis study reports on the preparation and characterization of epoxy/polyetherimide (EP/PEI) binary system containing low content of silver nanowires (AgNWs). The system was designed to form a co‐continuous structure during reaction‐induced phase separation of EP/PEI blend. With selective distribution of the AgNWs in continuous EP‐rich phase, a low percolation threshold at 3 wt% content of AgNWs was obtained in EP/PEI composite. The glass transition temperature, electrical conductivity, and thermal conductivity were all enhanced by the addition of low content of AgNWs. The surface resistivity of the EP/PEI blend decreased from 6.5 × 1016 Ω to 9.6 × 105 Ω with the addition of 3.0 wt% AgNWs, and meanwhile thermal conductivity was improved by 38.2%. Furthermore, AgNWs showed a critical impact on the kinetics of reaction‐induced phase separation and the formation of co‐continuous network structure. The process of phase separation of the thermosetting/thermoplastic blends was characterized by optical microscopy, time‐resolved light scattering, differential scanning calorimetry, and scanning electron microscopy.
Barriers towards effective pharmacovigilance systems of biosimilars in rheumatology: A Latin American survey
Authors: Castañeda‐Hernández Gilberto , Sandoval Hugo , Coindreau Javier , Rodriguez‐Davison Luis Felipe , Pineda Carlos 
Published: May 2019

AbstractPurposeThis review summarises the current status of regulatory guidelines for the approval of biosimilars in Latin America and highlights the main barriers to effective pharmacovigilance in this region. We also report results from a survey of Latin American rheumatologists assessing their understanding of prescribing biosimilars and the pharmacovigilance of these drugs.MethodsWe reviewed the current guidelines for the regulatory approval of biosimilars and barriers to effective pharmacovigilance in Latin American countries. Rheumatologists attending the II Pan‐American League of Rheumatology Associations PANLAR Review Course (Biosimilars update) in Lima, Peru were asked to complete a short survey to determine their knowledge of biosimilars.ResultsMany Latin American countries continue to lag behind Europe and the United States in establishing regulatory guidance and effective pharmacovigilance systems for biosimilars. Results from our survey also highlight a lack of awareness regarding the availability of biosimilars, their nomenclature, automatic substitution, and reporting adverse drug reactions because of these drugs.ConclusionsThe main barriers to effective pharmacovigilance in Latin America are the lack of consensus on the interchangeability of reference biologics and biosimilars, and the need for more suitably trained personnel to carry out effective postmarketing pharmacovigilance of biosimilars. Inconsistencies in biosimilar nomenclature make it difficult to adequately trace drugs and record adverse drug reactions associated with their use, creating a barrier to the global pharmacovigilance of biologics.
Construction of anion‐responsive crosslinked polypseudorotaxane based on molecular recognition of pillar[5]arene
Authors: Boominathan Muniyappan , Kiruthika Jeyavelraman , Arunachalam Murugan 
Published: May 2019

ABSTRACTA pillar[5]arene pendant polymer (Poly‐P[5]A) is synthesized via ROMP using Grubb's first‐generation catalyst. GPC analysis of the polymer suggested ~30 pendant pillar[5]arene units in the polymer. Supramolecular polypseudorotaxane assembly is constructed by intermolecularly crosslinking pendant pillar[5]arene units using a bispyridinium guest via host–guest complexation. Formation of the polypseudorotaxane assembly is characterized by 1D/2D NMR techniques and DLS analysis. Moreover, anion‐responsiveness of the polypseudorotaxane assembly is demonstrated by 1H NMR spectroscopic analysis using chloride anion as external stimulus. Scanning electron microscopic analysis of the poly‐P[5]A showed breath‐figure assembly and upon crosslinking with G.2PF6 the polymer self‐assemble to give a supramolecular polymer network. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1508–1515
Tumor‐Targeting W18O49 Nanoparticles for Dual‐Modality Imaging and Guided Heat‐Shock‐Response‐Inhibited Photothermal Therapy in Gastric Cancer
Authors: Yang Zhengyang , Wang Jiafeng , Liu Song , Sun Feng , Miao Ji , Xu En , Tao Liang , Wang Yuxin , Ai Shichao , Guan Wenxian 
Published: May 2019

AbstractPhotothermal therapy (PTT) is an emerging noninvasive and precise localized therapeutic modality; however, it is deeply limited by its poor tumor accumulation, inadequate photothermal conversion efficiency, and the thermoresistance of cancer cells. Aimed at these shortcomings, tumor‐targeting nanoparticles (iRGD‐W18O49‐17AAG) comprising carboxyl‐group‐functionalized W18O49 nanoparticles, integrin‐targeting peptide iRGD, and HSP90‐inhibitor 17AAG are developed. The W18O49 nanoparticles act as excellent PTT carriers and computed tomography (CT) imaging contrast agents. The ring type polypeptide iRGD promotes the accumulation of nanoparticles in the tumour and further penetration into cancer cells. The introduction of 17AAG can inhibit the heat‐shock response and overcome the thermoresistance, thus increasing the curative effect of PTT and reducing the chance of tumor recurrence. The W18O49 nanoparticles can also be used to monitor and guide the phototherapeutic through CT and near‐infrared fluorescence imaging after modification with Cy5.5. In addition, superior biosafety is also indicated in both preliminary in vitro and in vivo assessments. The potential of iRGD‐W18O49‐17AAG in tumor targeting, dual modality imaging‐guided and remarkable enhanced PTT of gastric cancer with ignorable side effect both in vitro and in vivo, which may be further applied in clinic, is highlighted.
Exploring the overlapping binding sites of ifenprodil and EVT‐101 in GluN2B‐containing NMDA receptors using novel chicken embryo forebrain cultures and molecular modeling
Authors: Fjelldal Marthe F. , Freyd Thibaud , Evenseth Linn M. , Sylte Ingebrigt , Ring Avi , Paulsen Ragnhild E. 
Published: May 2019

AbstractN‐methyl‐d‐aspartate receptors (NMDAR) are widely expressed in the brain. GluN2B subunit‐containing NMDARs has recently attracted significant attention as potential pharmacological targets, with emphasis on the functional properties of allosteric antagonists. We used primary cultures from chicken embryo forebrain (E10), expressing native GluN2B‐containing NMDA receptors as a novel model system. Comparing the inhibition of calcium influx by well‐known GluN2B subunit‐specific allosteric antagonists, the following rank order of potency was found: EVT‐101 (EC50 22 ± 8 nmol/L) > Ro 25‐6981 (EC50 60 ± 30 nmol/L) > ifenprodil (EC50 100 ± 40 nmol/L) > eliprodil (EC50 1300 ± 700 nmol/L), similar to previous observations in rat cortical cultures and cell lines overexpressing chimeric receptors. The less explored Ro 04‐5595 had an EC50 of 186 ± 32 nmol/L. Venturing to explain the differences in potency, binding properties were further studied by in silico docking and molecular dynamics simulations using x‐ray crystal structures of GluN1/GluN2B amino terminal domain. We found that Ro 04‐5595 was predicted to bind the recently discovered EVT‐101 binding site, not the ifenprodil‐binding site. The EVT‐101 binding pocket appears to accommodate more structurally different ligands than the ifenprodil‐binding site, and contains residues essential in ligand interactions necessary for calcium influx inhibition. For the ifenprodil site, the less effective antagonist (eliprodil) fails to interact with key residues, while in the EVT‐101 pocket, difference in potency might be explained by differences in ligand‐receptor interaction patterns.
Detoxification enzymes associated with butene‐fipronil resistance in Epacromius coerulipes
Authors: Jin Yongling , Gao Yugang , Zhang Haiyan , Wang Liyan , Yang Kejun , Dong Hui 
Published: May 2019

AbstractBACKGROUNDEpacromius coerulipes is a widely distributed locust pest species. Chemical control is the main method used to kill locusts; however, this can result in the selection of locusts with resistance to chemical pesticides. Therefore, the study of resistance is of great significance for the sustainable management of locusts.RESULTSIn this study, to investigate the relationship between detoxification enzymes and butene‐fipronil resistance in E. coerulipes, resistant strains of the locust were compared with sensitive strains. The synergism of synergistic agents was significantly enhanced, and the activities of multifunctional oxidase, carboxylesterase, and glutathione sulfur transferase were significantly increased. Transcriptome sequencing revealed 226 detoxification enzyme genes and 23 upregulated genes. Neighbor‐joining was used to construct a phylogenetic tree of related gene families, which included 59 P450 genes, 52 carboxylesterases (CarE) genes, and 25 glutathione S‐transferase (GST) genes. Reverse transcription polymerase chain reaction (RT‐PCR) analysis results of overexpressed genes in the resistant population combined with a phylogenetic tree showed that four P450 genes belonged to the CYP6, CYP4, CYP18 and CYP302 families, two CarE genes belonged to Clade A families, and one GST gene belonged to the Sigma family. These family members were annotated as detoxification enzyme genes of metabolic insecticide in the transcriptome databases.CONCLUSIONSThis study showed that P450, CarE and GST together resulted in moderate resistance to butene‐fipronil in locusts. The analysis revealed several overexpressed detoxification enzyme genes that will be the focus of future studies on the mechanism of resistance to butene‐fipronil. © 2019 Society of Chemical Industry
Protein elicitor PeaT1 enhanced resistance against aphid (Sitobion avenae) in wheat
Authors: Li Lin , Wang Shuangchao , Yang Xiufen , Francis Frederic , Qiu Dewen 
Published: May 2019

AbstractBACKGROUNDSitobion avenae, a dominant aphid in wheat that causes huge annual losses in agriculture, is mainly controlled using chemical pesticides. In this study, we investigated a protein elicitor, PeaT, for its induction of the defense response in wheat against Sitobion avenae.RESULTSIntrinsic rates of increase in second and third generations of S. avenae decreased in the PeaT1 (second generation 0.28 ± 0.03, third generation 0.26 ± 0.01) treatment compared with controls (second generation 0.31 ± 0.01, third generation 0.28 ± 0.01). S. avenae preferred to colonize control rather than PeaT1‐treated wheat seedlings in a host selection test. PeaT1‐treated wheat leaves possessed more trichomes and wax that formed a disadvantageous surface environment for S. avenae. Both salicylic acid (SA) and jasmonic acid (JA) accumulated significantly in PeaT1‐treated wheat seedlings.CONCLUSIONThese results showed that PeaT1 modified physical surface structures in wheat to reduce reproduction and deter colonization by S. avenae. SA and JA were involved in the induced physical defense process. This study provided evidence for use of PeaT1 as a ‘vaccine’ to protect wheat from Sitobion avenae. © 2019 Society of Chemical Industry
Differentiation of 2‐hydroxyglutarate enantiomers and its lactones by gas chromatography/electron ionization tandem mass spectrometry
Authors: Strain Shinji K. , Groves Morris D. , Emmett Mark R. 
Published: May 2019

Rationale2‐Hydroxyglutarate (2‐hg) exists as enantiomers and can readily undergo cyclization to its lactone. Gas chromatography/electron ionization mass spectrometry (GC/EI‐MS) has been used to separate 2‐hg enantiomers in bodily fluids but the assay cannot simultaneously measure cyclic and acylic 2‐hg enantiomers. Furthermore, the assignment of ion structures was not verified by complementary MS data.MethodsGC/EI‐MS and product ion analysis were used to obtain MS and MS/MS spectra of 2‐hg, deuterated and 13C‐labeled 2‐hg, and 2‐hg lactone. Ion structures and EI fragmentation mechanisms were determined by fragmentation pattern and isotopologue comparisons. Using the EI data, a GC/MS/MS assay was developed to separate and detect 2‐hg enantiomers and 2‐hg lactone enantiomers in blood and urine using a cyclodextrin capillary column.ResultsA new ion structure was predicted for the 85 m/z fragment than what was previously hypothesized, and the 117 m/z ion was the only fragment unique to the linear 2‐hg compound. MS/MS data suggested that the majority of the fragments were the result of secondary fragmentation. Finally, separation of serum and urine 2‐hg and 2‐hg lactone enantiomers was achieved, and the acyclic 2‐hg compound was found to be the major compound detected, though the amount of lactone detected was considerable in a number of samples.ConclusionsUnique EI fragmentation pathways for both 2‐hg and the 2‐hg lactone have been described. Subsequently, the GC/MS/MS assay presented herein has significant potential as a novel clinical assay as it separates and detects both 2‐hg enantiomers and the 2‐hg lactone enantiomers, a capability which has not been previously demonstrated by any other assay to date.