bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved Rate Control Reduces Cardiac Troponin T Levels in Permanent Atrial Fibrillation
Authors: Ulimoen Sara R. , Enger Steve , Norseth Jon , Pripp Are H. , Abdelnoor Michael , Arnesen Harald , Gjesdal Knut , Tveit Arnljot 
Published: April 2014

AbstractBackgroundDetectable levels of troponins are often found in serum of patients with atrial fibrillation (AF), and recent reports suggest that Tn concentrations are independently related to patient prognosis.HypothesisWe hypothesized that treatment with common rate‐reducing drugs might lower the levels of cardiac troponin T (TnT) in patients with permanent AF. We also wanted to investigate whether the different drugs would impact the Tn levels differently.MethodsSixty patients were included (mean age 71 ± 9 years, 18 women) in this randomized crossover study. All patients had stable, permanent AF without ischemic heart disease or congestive heart failure. Diltiazem 360 mg, verapamil 240 mg, metoprolol 100 mg, and carvedilol 25 mg were administered once daily for 3 weeks, in a randomized sequence. At baseline and on the last day of each treatment period, TnT concentrations were measured at rest and after a maximal exercise test.ResultsTnT was detectable in all patients. In 22% of the patients, TnT concentrations were above the threshold normally used for diagnosing myocardial infarction. All drugs reduced the levels of TnT significantly compared with baseline (P < 0.001 for all), but there were no significant differences between the treatments. Levels of TnT increased significantly in response to exercise testing (P < 0.001 for all).ConclusionsElevated TnT was demonstrated in a large proportion of stable patients with permanent AF without ischemic heart disease. A moderate reduction of heart rate by the study drugs was associated with a significant reduction in levels of TnT.
Phosphinic Acid Functionalized Polyazacycloalkane Chelators for Radiodiagnostics and Radiotherapeutics: Unique Characteristics and Applications
Authors: Notni Johannes , Šimeček Jakub , Wester Hans‐Jürgen 
Published: April 2014

AbstractGiven the wide application of positron emission tomography (PET), positron‐emitting metal radionuclides have received much attention recently. Of these, gallium‐68 has become particularly popular, as it is the only PET nuclide commercially available from radionuclide generators, therefore allowing local production of PET radiotracers independent of an on‐site cyclotron. Hence, interest in optimized bifunctional chelators for the elaboration of 68Ga‐labeled bioconjugates has been rekindled as well, resulting in the development of improved triazacyclononane‐triphosphinate (TRAP) ligand structures. The most remarkable features of these ligands are unparalleled selectivity for GaIII, rapid GaIII complexation kinetics, extraordinarily high thermodynamic stability, and kinetic inertness of the respective GaIII chelates. As a result, TRAP chelators exhibit very favorable 68Ga‐labeling properties. Based on the scaffolds NOPO (1,4,7‐triazacyclononane‐1,4‐bis[methylene(hydroxymethyl)phosphinic acid]‐7‐[methylene(2‐carboxyethyl)phosphinic acid]) and TRAP‐Pr, tailored for convenient preparation of 68Ga‐labeled monomeric and multimeric bioconjugates, a variety of novel 68Ga radiopharmaceuticals have been synthesized. These include bisphosphonates, somatostatin receptor ligands, prostate‐specific membrane antigen (PSMA)‐targeting peptides, and cyclic RGD pentapeptides, for in vivo PET imaging of bone, neuroendocrine tumors, prostate cancer, and integrin expression, respectively. Furthermore, TRAP‐based 68Ga‐labeled gadolinium(III) complexes have been proposed as bimodal probes for PET/MRI, and a cyclen‐based analogue of TRAP‐Pr has been suggested for the elaboration of targeted radiotherapeutics comprising radiolanthanide ions. Thus, polyazacycloalkane‐based polyphosphinic acid chelators are a powerful toolbox for pharmaceutical research, particularly for the development of 68Ga radiopharmaceuticals.
Neural proliferation in the dorsal root ganglia of the adult rat following capsaicin‐induced neuronal death
Authors: Gallaher Zachary R. , Johnston Stephen T. , Czaja Krzysztof 
Published: April 2014

ABSTRACTGlial proliferation is a major component of the nervous system's response to injury. In addition to glial proliferation, injury may induce neuronal proliferation in areas of the adult nervous system not considered neurogenic. We have previously reported increased neural proliferation within adult nodose ganglia following capsaicin‐induced neuronal death. However, proliferation within the dorsal root ganglia (DRG) remains to be characterized. We hypothesized that capsaicin‐induced neuronal death would increase proliferation of satellite glial cells (SGCs) within the DRG. To test this hypothesis, 6‐week‐old Sprague‐Dawley rats received a neurotoxic dose of capsaicin, and proliferation was quantified and characterized at multiple time points thereafter. Proliferation of satellite glial cells expressing the progenitor cell marker nestin was increased at 1 and 3 days following capsaicin administration as shown by BrdU incorporation. In addition to SGCs was a large population of proliferating resident macrophages, as shown by retrovirally mediated expression of GFP. SGC proliferation at these early time points was followed by recovery of neuronal numbers after a loss of 40% of the neuronal population in the DRG. This recovery in neuronal number correlated with recovery of function as shown by paw withdrawal from a noxious heat source. Further understanding of the role that glial proliferation plays in the recovery of neuronal numbers and function may lead to the development of therapeutic treatments for neurodegenerative conditions. J. Comp. Neurol. 522:3295–3307, 2014. © 2014 Wiley Periodicals, Inc.
Excavated Fe‐N‐C Sites for Enhanced Electrocatalytic Activity in the Oxygen Reduction Reaction
Authors: Jeong Beomgyun , Shin Dongyoon , Jeon Hongrae , Ocon Joey D. , Mun Bongjin Simon , Baik Jaeyoon , Shin Hyun‐Joon , Lee Jaeyoung 
Published: April 2014

AbstractPlatinum (Pt) is the best electrocatalyst for the oxygen reduction reaction (ORR) in hydrogen fuel cells, but it is an extremely expensive resource. The successful development of a cost‐effective non‐Pt ORR electrocatalyst will be a breakthrough for the commercialization of hydrogen‐air fuel cells. Ball milling has been used to incorporate metal and nitrogen precursors into micropores of carbon more effectively and in the direct nitrogen‐doping of carbon under highly pressurized nitrogen gas in the process of the preparation of non‐noble ORR catalysts. In this study, we first utilize ball milling to excavate the ORR active sites embedded in Fe‐modified N‐doped carbon nanofibers (Fe‐N‐CNFs) by pulverization. The facile ball‐milling process resulted in a significant enhancement in the ORR activity and the selectivity of the Fe‐N‐CNFs owing to the higher exposure of the metal‐based catalytically active sites. The degree of excavation of the Fe‐based active sites in the Fe‐N‐CNFs for the ORR was investigated with cyclic voltammetry, X‐ray photoelectron spectroscopy, and pore‐size distribution analysis. We believe that this simple approach is useful to improve alternative ORR electrocatalysts up to the level necessary for practical applications.
Fitness dynamics within a poplar hybrid zone: I.Prezygotic and postzygotic barriers impacting a native poplar hybrid stand
Authors: Roe Amanda D. , MacQuarrie Chris J. K. , Gros‐Louis Marie‐Claude , Simpson J. Dale , Lamarche Josyanne , Beardmore Tannis , Thompson Stacey L. , Tanguay Philippe , Isabel Nathalie 
Published: April 2014

AbstractHybridization and introgression are pervasive evolutionary phenomena that provide insight into the selective forces that maintain species boundaries, permit gene flow, and control the direction of evolutionary change. Poplar trees (PopulusL.) are well known for their ability to form viable hybrids and maintain their distinct species boundaries despite this interspecific gene flow. We sought to quantify the hybridization dynamics and postzygotic fitness within a hybrid stand of balsam poplar (Populus balsamiferaL.), eastern cottonwood (P. deltoidesMarsh.), and their natural hybrids to gain insight into the barriers maintaining this stable hybrid zone. We observed asymmetrical hybrid formation withP. deltoidesacting as the seed parent, but with subsequent introgression biased towardP. balsamifera. Native hybrids expressed fitness traits intermediate to the parental species and were not universally unfit. That said, native hybrid seedlings were absent from the seedling population, which may indicate additional selective pressures controlling their recruitment. It is imperative that we understand the selective forces maintaining this native hybrid zone in order to quantify the impact of exotic poplar hybrids on this native system.
Thermolysis of 4‐Diazotetrahydrofuran‐3‐ones: Total Change of Reaction Course Compared to Photolysis
Authors: Rodina Ludmila L. , Medvedev Jury J. , Galkina Olesia S. , Nikolaev Valerij A. 
Published: April 2014

AbstractThermolysis of 2,2,5,5‐tetrasubstituted 4‐diazodihydrofuran‐3‐ones in protic (BnOH) and aprotic (DMSO) media, in contrast to photolysis, gives rise to the formation of 2,2,4,5‐substituted 3(2H)‐furanones as a result of 1,2‐alkyl (aryl) shift. The thermal stability of diazodihydrofuranones in these processes is determined by the nature of the substituents at the C‐5 atom of the heterocyclic structure: alkyl and electron‐donating groups in the para‐position of the aryl substituent notably reduce the persistence of diazodihydrofuranones, whereas aryl groups and electron‐withdrawing substituents increase their stability considerably. Thermolysis of substituted 4‐diazodihydrofuran‐3‐ones in DMSO solution is a first‐order reaction that furnishes higher yields of furanones than thermolysis in BnOH. The reaction can serve as a preparative method for the synthesis of tetrasubstituted‐3(2H)‐furanones.
Consumer culture ideals, extrinsic motivations, and well‐being in children
Authors: Easterbrook Matthew J. , Wright Mark L. , Dittmar Helga , Banerjee Robin 
Published: April 2014

AbstractInternalising the consumer culture ideals of materialism and appearance has been shown to be negatively related to adults' well‐being. Similarly, adults who strive towards these ideals for extrinsic reasons, such as to improve their image or status, have been shown to have lower levels of well‐being than those who strive towards them for intrinsic reasons, such as to help others or support healthy relationships. However, to date, there is little evidence that these links exist in children. In the present research, we use new, age‐appropriate scales to test our predictions derived from self‐determination theory that being extrinsically motivated to achieve materialistic and appearance ideals will predict their internalisation, which, in turn, will negatively predict children's well‐being. An initial pilot study found that extrinsic motives were negatively related to well‐being in a sample of 150 children aged 8–11 years but that intrinsic motives were not. In our main study, we modelled materialism and appearance as indicators of a single underlying consumer culture construct, and, in a sample of 160 youths aged 8–15 years, found support for our hypothesis that being extrinsically motivated to achieve these consumer culture ideals predicts their internalisation, which negatively predicts well‐being. We discuss the possible mechanisms involved in these processes and the implications of these findings for future research. Copyright © 2014 John Wiley & Sons, Ltd.
Preparation, Characterization, and Bioelectrocatalytic Properties of Hemoglobin Incorporated Multiwalled Carbon Nanotubes‐Poly‐L‐lysine Composite Film Modified Electrodes Towards Bromate
Authors: Li Ying , Chen Shen‐Ming , Thangamuthu R. , Ajmal Ali M. , Al‐Hemaid Fahad M. A. 
Published: April 2014

AbstractThe present work describes preparation of hemoglobin‐incorporated multiwalled carbon nanotubes‐poly‐L‐lysine (MWCNT‐PLL)/Hb) composite modified electrode film modified glassy carbon electrode (GCE) and its electrocatalytic behavior towards reduction of bromate (${{\rm BrO}{{- \hfill \atop 3\hfill}}}$) in 0.1 M acetate buffer (pH 5.6). The modified electrode has been successfully fabricated by immobilizing hemoglobin on MWCNT dispersed in poly‐L‐lysine. The surface morphologies of MWCNT, PLL and Hb were characterized using atomic force microscopy (AFM). The voltammetric features suggested that the charge transport through the film was fast and the electrochemical behavior resembles that of surface‐confined redox species. Cyclic voltammetry was used to investigate the electrocatalytic behavior of the modified electrode towards bromate and was compared with that of the CNT‐modified as well as bare electrode. The analytical determination of bromate has been carried out in stirred solution at an optimized potential with a sensitivity of 7.56 μA mM−1 and the calibration curve was linear between 1.5×0−5 to 6.0×0−3 M.
The structural neuroanatomy of metacognitive insight in schizophrenia and its psychopathological and neuropsychological correlates
Authors: Spalletta Gianfranco , Piras Fabrizio , Piras Federica , Caltagirone Carlo , Orfei Maria Donata 
Published: April 2014

AbstractLack of insight into illness is a multidimensional phenomenon that has relevant implications on clinical course and therapy compliance. Here, we focused on metacognitive insight in schizophrenia, that is, the ability to monitor one's changes in state of mind and sensations, with the aim of investigating its neuroanatomical, psychopathological, and neuropsychological correlates. Fifty‐seven consecutive patients with Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) diagnosis of schizophrenia were administered the Insight Scale, and comprehensive psychopathological and neuropsychological batteries. They underwent a high‐resolution T1‐weighted magnetic resonance imaging investigation. Gray matter (GM) and white matter (WM) volumes were analyzed on a voxel‐by‐voxel basis using Statistical Parametric Mapping 8. Reduced metacognitive insight was related to reduced GM volumes in the left ventrolateral prefrontal cortex, right dorsolateral prefrontal cortex and insula, and bilateral premotor area and putamen. Further, it was related to reduced WM volumes of the right superior longitudinal fasciculum, left corona radiata, left forceps minor, and bilateral cingulum. Increased metacognitive insight was related to increased depression severity and attentional control impairment, while the latter was related to increased GM volumes in brain areas linked to metacognitive insight. Results of this study suggest that prefrontal GM and WM bundles, all implied in cognitive control and self‐reflection, may be the neuroanatomical correlates of metacognitive insight in schizophrenia. Further, higher metacognitive insight is hypothesized to be a risk factor for depression which may subsequently impair attention. This line of research may provide the basis for the development of cognitive interventions aimed at improving self‐monitoring and compliance to treatment. Hum Brain Mapp 35:4729–4740, 2014. © 2014 Wiley Periodicals, Inc.
Diagnostic classification of arterial spin labeling and structural MRI in presenile early stage dementia
Authors: Bron Esther E. , Steketee Rebecca M.E. , Houston Gavin C. , Oliver Ruth A. , Achterberg Hakim C. , Loog Marco , van Swieten John C. , Hammers Alexander , Niessen Wiro J. , Smits Marion , Klein Stefan ,   for the Alzheimer's Disease Neuroimaging Initiative
Published: April 2014

AbstractBecause hypoperfusion of brain tissue precedes atrophy in dementia, the detection of dementia may be advanced by the use of perfusion information. Such information can be obtained noninvasively with arterial spin labeling (ASL), a relatively new MR technique quantifying cerebral blood flow (CBF). Using ASL and structural MRI, we evaluated diagnostic classification in 32 prospectively included presenile early stage dementia patients and 32 healthy controls. Patients were suspected of Alzheimer's disease (AD) or frontotemporal dementia. Classification was based on CBF as perfusion marker, gray matter (GM) volume as atrophy marker, and their combination. These markers were each examined using six feature extraction methods: a voxel‐wise method and a region of interest (ROI)‐wise approach using five ROI‐sets in the GM. These ROI‐sets ranged in number from 72 brain regions to a single ROI for the entire supratentorial brain. Classification was performed with a linear support vector machine classifier. For validation of the classification method on the basis of GM features, a reference dataset from the AD Neuroimaging Initiative database was used consisting of AD patients and healthy controls. In our early stage dementia population, the voxelwise feature‐extraction approach achieved more accurate results (area under the curve (AUC) range = 86 − 91%) than all other approaches (AUC = 57 − 84%). Used in isolation, CBF quantified with ASL was a good diagnostic marker for dementia. However, our findings indicated only little added diagnostic value when combining ASL with the structural MRI data (AUC = 91%), which did not significantly improve over accuracy of structural MRI atrophy marker by itself. Hum Brain Mapp 35:4916–4931, 2014. © 2014 Wiley Periodicals, Inc.
Groundwater temperature evolution in the subsurface urban heat island of Cologne, Germany
Authors: Zhu Ke , Bayer Peter , Grathwohl Peter , Blum Philipp 
Published: March 2014

AbstractLong‐term heating of shallow urban aquifers is observed worldwide. Our measurements in the city of Cologne, Germany revealed that the groundwater temperatures found in the city centre are more than 5 K higher than the undisturbed background. To explore the role of groundwater flow for the development of subsurface urban heat islands, a numerical flow and heat transport model is set up, which describes the hydraulic conditions of Cologne and simulates the transient evolution of thermal anomalies in the urban ground. A main focus is on the influence of horizontal groundwater flow, groundwater recharge and trends in local ground warming. To examine heat transport in groundwater, a scenario consisting of a local hot spot with a length of 1 km of long‐term ground heating was set up in the centre of the city. Groundwater temperature‐depth profiles at upstream, central and downstream locations of this hot spot are inspected. The simulation results indicate that the main thermal transport mechanisms are long‐term vertical conductive heat input, horizontal advection and transverse dispersion. Groundwater recharge rates in the city are low (<100 mm a−1) and thus do not significantly contribute to heat transport into the urban aquifer. With groundwater flow, local vertical temperature profiles become very complex and are hard to interpret, if local flow conditions and heat sources are not thoroughly known. Copyright © 2014 John Wiley & Sons, Ltd.
Floodplain connection buffers seasonal changes in urban stream water quality
Authors: Ledford Sarah H. , Lautz Laura K. 
Published: March 2014

AbstractUrban streams in the Northeastern United States have large road salt inputs during the winter, increased nonpoint sources of inorganic nitrogen and decreased short‐term and permanent storage of nutrients. Restoration activities that re‐establish connection between streams and riparian environments may be effective for improving urban stream water quality. Meadowbrook Creek, a first‐order stream in Syracuse, NY, provides a unique setting to explore impacts of stream–floodplain connection because it flows along a negative urbanization gradient, from channelized and armoured headwaters to a broad, vegetated floodplain with a riparian aquifer. In this study, we investigated how reconnection to groundwater and introduction of riparian vegetation impacted urban surface water chemistry by making biweekly longitudinal surveys of stream water chemistry in the creek from May 2012 until June 2013. We used multiple methods to measure groundwater discharge rates along the creek. Chloride concentrations in the upstream, disconnected reach were influenced by discharge of road salt during snow melt events and ranged from 161.2 to 1440 mg/l. Chloride concentrations in the downstream, connected reach had less temporal variation, ranging from 252.0 to 1049 mg/l, because of buffering by groundwater discharge, as groundwater chloride concentrations ranged from 84.0 to 655.4 mg/l. In the summer, there was little to no nitrate in the disconnected reach because of limited sources and high primary productivity, but concentrations reached over 1 mg N/l in the connected reach because of the presence of riparian vegetation. During the winter, when temperatures fell below freezing, nitrate concentrations in the disconnected reach increased to 0.58 mg N/l but were still lower than the connected reach, which averaged 0.88 mg N/l. Urban stream restoration projects that restore floodplain connection may impact water quality by storing high salinity road run‐off during winter overbank events and discharging that water year‐round, thereby attenuating seasonal fluctuations in chloride. Contrary to prior findings, we observed that floodplain connection and riparian vegetation may alter nitrate sources and sinks such that nitrate concentrations increase longitudinally in connected urban streams. Copyright © 2014 John Wiley & Sons, Ltd.
Population pharmacokinetics of hydroxyurea for children and adolescents with sickle cell disease
Authors: Wiczling Paweł , Liem Robert I. , Panepinto Julie A. , Garg Uttam , Abdel‐Rahman Susan M. , Kearns Gregory L. , Neville Kathleen A. 
Published: April 2014

AbstractThe objective of this study was to develop a population pharmacokinetic (PK) model sufficient to describe hydroxyurea (HU) concentrations in serum and urine following oral drug administration in pediatric patients with sickle cell disease. Additionally, the measured hydroxyurea concentrations for particular sampling time were correlated with exposure measures (AUC) to find the most predictive relationship. Hydroxyurea concentrations were determined in 21 subjects. Using a population nonlinear mixed‐effect modeling, the HU PK was best described by a one‐compartment model with two elimination pathways (metabolic and renal) and a transit compartment absorption. The typical mean absorption time was 0.222 hour. The typical apparent volume of distribution was 21.8 L and the apparent systemic clearance was 6.88 L/h for an average weight patient of 30.7 kg. The 50% of the HU dose was renally excreted. Linear correlations were apparent between the plasma HU concentration at 1, 1.5, 2, 4, and 6 hours post‐dose and AUC with the most significant (R2 = 0.71) observed at 1.5 hours. A population PK model was successful in describing HU disposition in plasma and urine. Data from the model also demonstrated that HU plasma concentrations at 1.5 hours after an oral dose of the drug were highly predictive of systemic drug exposure.