bluuebunny/crossref_metadata_2025_split huggingface dataset:
Copeptin, a surrogate marker for arginine vasopressin secretion, is positively associated with glucagon
Authors: Lundegaard Asferg C. , Bjørn Andersen U. , Linneberg A. , Goetze J. P. , Holst J. J. , Jeppesen J. L. 
Published: September 2018

AbstractAimTo explore the association of plasma copeptin, the C‐terminal portion of provasopressin and a stable surrogate marker for arginine vasopressin secretion, with plasma glucagon in obese men and men of normal weight.MethodsWe measured fasting blood concentrations of copeptin and glucagon in 102 healthy obese men (mean ± sd age 49.4 ± 10.2 years) and a control group 27 healthy men of normal weight (mean ± sd age 51.5 ± 8.4 years). Differences between groups were evaluated using t‐tests, and multiple linear regression analysis, adjusting for age and weight status (normal weight vs obese), was used to calculate unstandardized regression coefficients (β) with 95% CIs between copeptin and glucagon. Copeptin was (natural) log‐transformed.ResultsThe obese men had higher [median (interquartile range)] plasma copeptin concentrations [6.6 (4.6–9.5) vs 4.9 (3.5–6.8) pmol/l; P = 0.040] and higher mean ± sd plasma glucagon concentrations (8.5 ± 3.8 vs 5.3 ± 1.4 pmol/l; P < 0.001) than the normal‐weight men. Adjusted for age and weight status, copeptin was significantly associated with glucagon (β = 1.35, 95% CI 0.13–2.57; P = 0.031). No significant interaction effect between copeptin and weight status on glucagon was found (P = 0.81).ConclusionsObese men had higher concentrations of copeptin and glucagon than men of normal weight. Copeptin was positively associated with glucagon. Our data suggest that increased arginine vasopressin‐stimulated glucagon secretion might contribute to higher glucagon concentrations; therefore, increased arginine vasopressin secretion, in addition to other factors, could further aggravate the hyperglucagonaemic state found in obese individuals.
Effect of liraglutide on ambulatory blood pressure in patients with hypertension and type 2 diabetes: A randomized, double‐blind, placebo‐controlled trial
Authors: Liakos Aris , Lambadiari Vaia , Bargiota Alexandra , Kitsios Konstantinos , Avramidis Iakovos , Kotsa Kalliopi , Gerou Spyridon , Boura Panagiota , Tentolouris Nikolaos , Dimitriadis George , Tsapas Apostolos 
Published: September 2018

AimsTo assess the effect of liraglutide on 24‐hour ambulatory blood pressure and heart rate in patients with hypertension (pre‐ and stage 1 hypertension) and inadequately controlled Type 2 diabetes (glycated haemoglobin 7%–10% [53‐86 mmol/mol]).Materials and methodsEligible patients for this investigator‐initiated, parallel‐group, randomized, double‐blind trial were on stable background antihyperglycaemic therapy excluding insulin, glucagon‐like peptide‐1 receptor agonists and dipeptidyl‐peptidase‐4 inhibitors. Participants were centrally randomized in a 1:1 ratio to daily liraglutide 0.6 mg, titrated to 1.2 mg after the first week, or placebo for 5 weeks. The primary outcome was change in 24‐hour ambulatory systolic blood pressure (SBP), and secondary outcomes included change in ambulatory diastolic blood pressure (DBP) and heart rate. We also assessed renal sodium handling.ResultsOf 87 patients assessed for eligibility, 62 (66.1% men) with a mean age of 60.2 years were randomized to liraglutide (n = 31) or placebo (n = 31). All participants received background therapy with metformin, whilst 35.5% were treated concomitantly with sulphonylureas and 14.5% with pioglitazone. Compared with placebo, liraglutide reduced 24‐hour SBP by −5.73 mm Hg (95% confidence interval [CI] –9.81 to −1.65) and had a neutral effect on 24‐hour DBP (mean difference − 1.42 mm Hg; 95% CI –4.25 to 1.40), whilst increasing 24‐hour heart rate by 6.16 beats/min (95% CI 3.25 to 9.07). Findings were consistent for daytime and night‐time measurements. Liraglutide did not increase urine sodium excretion.ConclusionBased on 24‐hour ambulatory measurements, short‐term treatment with liraglutide had a favourable effect on SBP whilst increasing heart rate.
Phase‐locked responses to the vowel envelope vary in scalp‐recorded amplitude due to across‐frequency response interactions
Authors: Easwar Vijayalakshmi , Banyard Ashlee , Aiken Steven J. , Purcell David W. 
Published: September 2018

AbstractNeural encoding of the envelope of sounds like vowels is essential to access temporal information useful for speech recognition. Subcortical responses to envelope periodicity of vowels can be assessed using scalp‐recorded envelope following responses (EFRs); however, the amplitude of EFRs vary by vowel spectra and the causal relationship is not well understood. One cause for spectral dependency could be interactions between responses with different phases, initiated by multiple stimulus frequencies. Phase differences can arise from earlier initiation of processing high frequencies relative to low frequencies in the cochlea. This study investigated the presence of such phase interactions by measuring EFRs to two naturally spoken vowels (/ε/ and /u/), while delaying the envelope phase of the second formant band (F2+) relative to the first formant (F1) band in 45° increments. At 0° F2+ phase delay, EFRs elicited by the vowel /ε/ were lower in amplitude than the EFRs elicited by /u/. Using vector computations, we found that the lower amplitude of /ε/‐EFRs was caused by linear superposition of F1‐ and F2+‐contributions with larger F1‐F2+ phase differences (166°) compared to /u/ (19°). While the variation in amplitude across F2+ phase delays could be modeled with two dominant EFR sources for both vowels, the degree of variation was dependent on F1 and F2+ EFR characteristics. Together, we demonstrate that (a) broadband sounds like vowels elicit independent responses from different stimulus frequencies that may be out‐of‐phase and affect scalp‐based measurements, and (b) delaying higher frequency formants can maximize EFR amplitudes for some vowels.
Glial mechanisms underlying substance use disorders
Authors: Linker K. E. , Cross S. J. , Leslie F. M. 
Published: September 2018

AbstractAddiction is a devastating disorder that produces persistent maladaptive changes to the central nervous system, including glial cells. Although there is an extensive body of literature examining the neuronal mechanisms of substance use disorders, effective therapies remain elusive. Glia, particularly microglia and astrocytes, have an emerging and meaningful role in a variety of processes beyond inflammation and immune surveillance, and may represent a promising therapeutic target. Indeed, glia actively modulate neurotransmission, synaptic connectivity and neural circuit function, and are critically poised to contribute to addictive‐like brain states and behaviors. In this review, we argue that glia influence the cellular, molecular, and synaptic changes that occur in neurons following drug exposure, and that this cellular relationship is critically modified following drug exposure. We discuss direct actions of abused drugs on glial function through immune receptors, such as Toll‐like receptor 4, as well as other mechanisms. We highlight how drugs of abuse affect glia‐neural communication, and the profound effects that glial‐derived factors have on neuronal excitability, structure, and function. Recent research demonstrates that glia have brain region‐specific functions, and glia in different brain regions have distinct contributions to drug‐associated behaviors. We will also evaluate the evidence demonstrating that glial activation is essential for drug reward and drug‐induced dopamine release, and highlight clinical evidence showing that glial mechanisms contribute to drug abuse liability. In this review, we synthesize the extensive evidence that glia have a unique, pivotal, and underappreciated role in the development and maintenance of addiction.
Human posterior parietal cortex responds to visual stimuli as early as peristriate occipital cortex
Authors: Regev Tamar I. , Winawer Jonathan , Gerber Edden M. , Knight Robert T. , Deouell Leon Y. 
Published: September 2018

AbstractMuch of what is known about the timing of visual processing in the brain is inferred from intracranial studies in monkeys, with human data limited to mainly noninvasive methods with lower spatial resolution. Here, we estimated visual onset latencies from electrocorticographic (ECoG) recordings in a patient who was implanted with 112 subdural electrodes, distributed across the posterior cortex of the right hemisphere, for presurgical evaluation of intractable epilepsy. Functional MRI prior to surgery was used to determine boundaries of visual areas. The patient was presented with images of objects from several categories. Event‐related potentials (ERPs) were calculated across all categories excluding targets, and statistically reliable onset latencies were determined, using a bootstrapping procedure over the single trial baseline activity in individual electrodes. The distribution of onset latencies broadly reflected the known hierarchy of visual areas, with the earliest cortical responses in primary visual cortex, and higher areas showing later responses. A clear exception to this pattern was a robust, statistically reliable and spatially localized, very early response, on the bank of the posterior intraparietal sulcus (IPS). The response in the IPS started nearly simultaneously with responses detected in peristriate visual areas, around 60 ms poststimulus onset. Our results support the notion of early visual processing in the posterior parietal lobe, not respecting traditional hierarchies, and give direct evidence for onset times of visual responses across the human cortex.
Demand elasticity predicts addiction endophenotypes and the therapeutic efficacy of an orexin/hypocretin‐1 receptor antagonist in rats
Authors: James Morgan H. , Bowrey Hannah E. , Stopper Colin M. , Aston‐Jones Gary 
Published: September 2018

AbstractBehavioral economics is a powerful, translational approach for measuring drug demand in both humans and animals. Here, we asked if demand for cocaine in rats with limited drug experience could be used to identify individuals most at risk of expressing an addiction phenotype following either long‐ or intermittent access self‐administration schedules, both of which model the transition to uncontrolled drug‐seeking. Because the orexin‐1 receptor antagonist SB‐334867 (SB) is particularly effective at reducing drug‐seeking in highly motivated individuals, we also asked whether demand measured after prolonged drug experience could predict SB efficacy. Demand elasticity (α) measured immediately following acquisition of cocaine self‐administration (‘baseline α’) was positively correlated with α assessed after 2w of long‐ or intermittent access. Baseline α also predicted the magnitude of compulsive responding for cocaine, drug‐seeking in initial abstinence and cued reinstatement following long‐, intermittent‐ or standard short access. When demand was measured after these differential access conditions, α predicted the same addiction endophenotypes predicted by baseline α, as well as primed reinstatement and the emergence of negative emotional mood behavior following abstinence. α also predicted the efficacy of SB, such that high demand rats showed greater reductions in motivation for cocaine following SB compared to low demand rats. Together, these findings indicate that α might serve as a behavioral biomarker to predict individuals most likely to progress from controlled to uncontrolled drug use, and to identify individuals most likely to benefit from orexin‐based therapies for the treatment of addiction.
New insights on relaxant effects of (—)‐borneol monoterpene in rat aortic rings
Authors: Santos Stefânia E. , Ribeiro Fernanda P.R.A. , Menezes Pedro M.N. , Duarte‐Filho Luiz A.M. , Quintans Jullyana S.S. , Quintans‐Junior Lucindo J. , Silva Fabricio S. , Ribeiro Luciano A.A. 
Published: September 2018

AbstractThe monoterpene alcohol (−)‐borneol has many biological effects such as sedative, anti‐inflammatory, analgesic, anti‐nociceptive, antithrombotic and vasorelaxant effects. Our objective in this study was to investigate the mechanism of action of (−)‐borneol and determine its vasorelaxant effect. (−)‐Borneol was tested on isolated aortic rings contracted with PE (10−6 m). This study was performed in the absence or in the presence of endothelium, L‐NAME (100 μm), indomethacin (10 μm), TEA (1 and 10 mm), 4‐AP (1 mm) or glibenclamide (1 mm) to assess the participation of EDRF, nitric oxide, prostanoids and potassium channels on the relaxing effect of (−)‐borneol. In this work, (−)‐borneol induced a relaxant effect in aortic rings, with and without endothelium, in a concentration‐dependent manner. The pharmacological characterization obtained using L‐NAME, indomethacin, TEA, 4‐AP and glibenclamide demonstrates that the effect of (−)‐borneol was modified in the presence of L‐NAME, indomethacin and glibenclamide showing that these signal transduction pathways are involved in the relaxing effect of the monoterpene. (−)‐Borneol has a vasorelaxant effect that depends on the presence of vascular endothelium, with the participation of nitric oxide and prostanoids. Also, (−)‐borneol displayed a direct action on the vascular smooth muscle, greatly dependent on KATP channels.
Risk governance: Examining its impact upon bank performance and risk‐taking
Authors: Gontarek Walter , Belghitar Yacine 
Published: September 2018

AbstractAs policy‐makers in the United States contemplate a relaxation of financial regulation, our study contributes to this dialogue by testing the veracity of heightened standards of risk governance activities for US bank holding companies (BHCs). Our study examines evidence relating to the adoption of these standards by BHCs following regulatory intervention. We find that board‐level risk appetite practices have a profound association upon BHC performance and tail risk. Our estimates show that BHCs which adopt risk appetite practices exhibit a significant improvement in headline performance and reduced tail risk measures. Our research is relevant to academics by identifying the significance of this risk governance practice which has been introduced by global regulators. For practitioners (including board members, risk managers, policy‐makers and regulators), our study validates the efficacy of risk appetite frameworks as the future shape of financial regulation is being actively debated in the US.
Cascading effects from plants to soil microorganisms explain how plant species richness and simulated climate change affect soil multifunctionality
Authors: Valencia Enrique , Gross Nicolas , Quero José L. , Carmona Carlos P. , Ochoa Victoria , Gozalo Beatriz , Delgado‐Baquerizo Manuel , Dumack Kenneth , Hamonts Kelly , Singh Brajesh K. , Bonkowski Michael , Maestre Fernando T. 
Published: September 2018

AbstractDespite their importance, how plant communities and soil microorganisms interact to determine the capacity of ecosystems to provide multiple functions simultaneously (multifunctionality) under climate change is poorly known. We conducted a common garden experiment using grassland species to evaluate how plant functional structure and soil microbial (bacteria and protists) diversity and abundance regulate soil multifunctionality responses to joint changes in plant species richness (one, three and six species) and simulated climate change (3°C warming and 35% rainfall reduction). The effects of species richness and climate on soil multifunctionality were indirectly driven via changes in plant functional structure and their relationships with the abundance and diversity of soil bacteria and protists. More specifically, warming selected for the larger and most productive plant species, increasing the average size within communities and leading to reductions in functional plant diversity. These changes increased the total abundance of bacteria that, in turn, increased that of protists, ultimately promoting soil multifunctionality. Our work suggests that cascading effects between plant functional traits and the abundance of multitrophic soil organisms largely regulate the response of soil multifunctionality to simulated climate change, and ultimately provides novel experimental insights into the mechanisms underlying the effects of biodiversity and climate change on ecosystem functioning.
Assessment of Dissolution of Silicate Rock Reference Materials with Ammonium Bifluoride and Nitric Acid in a Microwave Oven
Authors: Magaldi Thais T. , Navarro Margareth S. , Enzweiler Jacinta 
Published: September 2018

The complete dissolution of representative test portions of powdered rock samples for the determination of the mass fractions of trace elements by ICP‐MS relies either on aggressive and time‐consuming acid digestions or fusion/sintering with appropriate fluxes. Here, we evaluate a microwave oven dissolution method that employs a solution of NH4HF2 and HNO3. The entire procedure occurs in a closed vessel system and takes up to 4 h. In hundreds of digestions, the precipitation of fluorides was never observed. Replicate decomposition of 100 mg of twenty‐one international reference materials (RMs) of igneous rocks, and also one of a shale presented mostly satisfactory recoveries of forty‐one trace elements. Important exceptions were Zr and Hf in G‐2 and GSP‐2 (mean recoveries of ca. 70%), although for four other felsic rock RMs, the digestion was complete. For ultramafic rock RMs, we present Cr results that indicate quantitative dissolution of Cr‐bearing phases. We discuss the findings and conclude that advances in sample preparation of geological materials for instrumental analysis would benefit from a better understanding of how specific characteristics, such as composition and crystallinity of certain minerals, may affect their reactivity.
Neurofilament is superior to cytokeratin 20 in supporting cutaneous origin for neuroendocrine carcinoma
Authors: Stanoszek Lauren M , Chan May P , Palanisamy Nallasivam , Carskadon Shannon , Siddiqui Javed , Patel Rajiv M , Harms Kelly L , Lowe Lori , Fullen Douglas R , Harms Paul W 
Published: September 2018

AimPrimary cutaneous neuroendocrine carcinoma, or Merkel cell carcinoma (MCC), cannot be distinguished morphologically from small‐cell neuroendocrine carcinomas (SmCC) from other sites. Immunohistochemistry is required to confirm cutaneous origin, and is also used for detection of sentinel lymph node (SLN) metastases of MCC. Cytokeratin 20 (CK20) expression is commonly used for these purposes, but is negative in some MCC cases, and has unclear specificity. We evaluated immunohistochemistry for neurofilament and CK20 in MCC compared with SmCC from other sites.Methods and resultsWe evaluated neurofilament expression in 55 MCC specimens from 39 unique patients, including nine CK20‐negative MCC tumours. Neurofilament expression was observed in 42 of 55 (76.4%) MCC cases, including seven of nine (77.8%) CK20‐negative MCC cases. Neurofilament was expressed in nine of 12 (75%) Merkel cell polyomavirus‐positive tumours and five of 10 (50%) virus‐negative tumours. Compared to a standard immunohistochemical panel (cytokeratin cocktail and CK20), neurofilament was 87.5% sensitive for detecting SLN metastases. Neurofilament and CK20 expression was also assessed in 61 extracutaneous SmCC from 60 unique patients, with primary sites including lung (27), bladder (18), cervix (3), gastrointestinal tract (3), sinonasal tract (2) and other sites (7). The specificity of neurofilament and CK20 for MCC versus non‐cutaneous SmCC was 96.7% and 59.0%, respectively.ConclusionsNeurofilament has superior specificity to CK20 in distinguishing MCC from non‐cutaneous SmCC. Neurofilament is frequently expressed in CK20‐ and virus‐negative MCC tumours. Limitations of neurofilament immunohistochemistry include lower sensitivity than CK20 and subtle staining in some tumours. However, our findings indicate that neurofilament is useful for excluding non‐cutaneous SmCC.
CURRENCY UNION WITH OR WITHOUT BANKING UNION
Authors: Bignon Vincent , Breton Régis , Rojas Breu Mariana 
Published: September 2018

AbstractWe build a symmetric two‐country monetary model with credit to study the interplay between currency integration and credit markets integration. The currency arrangement affects credit availability through default incentives. We capture credit markets integration by the extra cost incurred to obtain credit for cross‐border transactions and, with the euro area context in mind, label as banking union a situation where this cost is low. For high levels of the cross‐border credit cost, currency integration may magnify default incentives, leading to more credit rationing and lower welfare. The integration of credit markets restores the optimality of the currency union.
Viscosities and working region predictions for bismuth aluminoborosilicate glasses
Authors: Gardner Levi D. , Riley Brian J. , Elliott Casey , Simpson Michael , Carlson Krista 
Published: September 2018

AbstractBismuth aluminoborosilicate glasses were prepared using a standard melt‐quench technique, and the viscosity and thermal properties were measured and analyzed. Electron microprobe analysis was used to examine glass homogeneity. Fragility was calculated based on Mauro–Yue–Ellison–Gupta–Allan model fits to the viscosity curves. The system is characterized by an open structure with high fragility (44‐59). Based on microanalysis and differential scanning calorimetry results, the addition of network intermediate Al2O3appears to mitigate both phase separation and crystallization. From thermal property data, mixture models were created to predict the glass transition temperatures and softening temperatures as functions of composition. Based on K‐fold validation findings, the first‐order mixture model predictions of glass transition and softening appear to approximate actual values better than models with any additional second‐order terms.