bluuebunny/crossref_metadata_2025_split huggingface dataset:
Primed Conversion: The New Kid on the Block for Photoconversion
Authors: Mohr Manuel Alexander , Pantazis Periklis 
Published: February 2018

AbstractIn 2015, a novel way to convert photoconvertible fluorescent proteins was reported that uses the intercept of blue and far‐red light instead of traditional violet or near‐UV light illumination. This Minireview describes and contrasts this distinct two‐step mechanism termed primed conversion with traditional photoconversion. We provide a comprehensive overview of what is known to date about primed conversion and focus on the molecular requirements for it to take place. We provide examples of its application to axially confined photoconversion in complex tissues as well as super‐resolution microscopy. Further, we describe why and when it is useful, including its advantages and disadvantages, and give an insight into potential future development in the field.
An Optical Sensor Array Discriminates Syrups and Honeys
Authors: Bojanowski N. Maximilian , Hainer Felix , Bender Markus , Seehafer Kai , Bunz Uwe H. F. 
Published: February 2018

AbstractWe report a cross‐reactive sensor array, combining a two‐component probe system based upon three viologen substituted boronic acids and a poly(aryleneethynylene) (PAE) and an additional number of simple PAEs alone. This combined system discriminates 27 different honeys in aqueous solution, according to patterns in fluorescence intensity modulation, using linear discriminant analysis for data processing. The fluorescence turn‐on array detects saccharide composition, while the PAEs discriminate trace colored components in the honeys.
Anion Recognition in Water, Including Sulfate, by a Bicyclam Bimetallic Receptor: A Process Governed by the Enthalpy/Entropy Compensatory Relationship
Authors: Boiocchi Massimo , Bonizzoni Marco , Ciarrocchi Carlo , Fabbrizzi Luigi , Invernici Michele , Licchelli Maurizio 
Published: February 2018

AbstractThe dimetallic system [CuII2(L)]4+ contains two facing equivalent metallocyclam subunits and incorporates ambidentate anions, mono‐ (halides) and poly‐atomic (sulfate), which bridge the two CuII centres. Isothermal titration calorimetry (ITC) experiments in water showed that the log K values of the inclusion equilibria for halides and sulfate varied over a restricted interval (3.6±0.2), which indicated lack of selectivity and that similarity of ΔG° values resulted from the unbalanced contribution of the ΔH° and TΔS° terms: the more favourable the one, the less favourable the other. In particular, a linear dependence of ΔH° and TΔS° was observed (a typical enthalpy/entropy compensatory diagram), which assigned a major role to hydration terms: 1) a more hydrated anion resulted in a more endothermic dehydration process; and 2) a larger number of water molecules released to the solution resulted in a more positive TΔS°. Limiting cases refer to the complexation 1) of the poorly hydrated iodide (highly exothermic process, entropically disfavoured), and 2) of the highly hydrated sulfate (moderately endothermic process, entropically very favoured). Anion receptors operating in water belong to two main domains: 1) those exhibiting positive ΔH° and positive TΔS° (+/+ signature), and 2) those displaying the opposite behaviour: (−/− signature). The receptor investigated herein connects the two domains, along the ΔH°/TΔS° straight line, thanks to the hidden role of the versatile metal–anion interaction.
Probing Magnetic‐Exchange Coupling in Supramolecular Squares Based on Reducible Tetrazine‐Derived Ligands
Authors: Lemes Maykon A. , Stein Hilarie N. , Gabidullin Bulat , Robeyns Koen , Clérac Rodolphe , Murugesu Muralee 
Published: February 2018

AbstractReducible 3,6‐bis(3,5‐dimethyl‐pyrazolyl)1,2,4,5‐tetrazine was employed to isolate supramolecular air‐stable [Co4] and [Zn4] squares, which were achieved via careful selection of counterions rather than the use of reducing agents. Magnetic susceptibility studies revealed a strong radical‐CoII exchange coupling (Jrad‐Co/hc=−118 cm−1, −2J formalism) with a spin ground state of ST=4, whereas the unreduced analogue revealed negligible coupling between the Co centers (JCo‐Co/hc=−0.64 cm−1). Radical–radical coupling was also probed in the [Zn4] congener, which led to Jrad‐rad/hc=−15.9(5) cm−1. These results highlight the versatile air‐stable coordination chemistry of tetrazine and the importance of exploiting easily reducible delocalized radical to promote strong exchange coupling between spin carriers.
Trajectories of income and social benefits for mothers and fathers of children with cancer: A national cohort study in Sweden
Authors: Hiyoshi Ayako , Montgomery Scott , Bottai Matteo , Hovén Emma I. 
Published: February 2018

BACKGROUNDThe contribution of different income sources from work and social benefits to trajectories of income for the parents of children with cancer has not been empirically investigated.METHODSUsing Swedish registers, parents of children with an incidence cancer diagnosis between 2004 and 2009 were identified and matched with parents of children without cancer (reference parents). A total of 20,091 families were followed from the year before the diagnosis to a maximum of 8 years. Generalized linear models estimated the ratios of mean incomes from work and social benefits and of its total.RESULTSAround the time of the child's cancer diagnosis, the total income was on average up to 6% higher among the mothers of children with cancer compared with reference mothers, but no differences were noted among fathers. Income from work dropped to the lowest level around the time of a cancer diagnosis, with swift recovery noted for fathers but not for mothers. Sickness and childcare‐related benefits were up to 6 times larger for the parents of children with cancer than reference parents. As social benefits diminished after approximately 3 years, the total income of mothers of children with cancer became lower than that of reference mothers, and the gap widened over time.CONCLUSIONSSocial benefits appeared to ease the financial burden during the years around a cancer diagnosis. However, mothers experienced persistently lower income after benefits diminished. Experiences differed by single‐parent versus dual‐parent households, the survival of the child with cancer, and other relevant characteristics. Further investigation is needed for potential long‐term consequences for mothers, including their career and future pension in retirement. Cancer 2018;124:1492‐500. © 2018 American Cancer Society.
Effects of fibroblast‐myocyte coupling on the sinoatrial node activity: A computational study
Authors: Karpaev Alexey A. , Syunyaev Roman A. , Aliev Rubin R. 
Published: February 2018

AbstractWhile the sinoatrial node (SAN) is structurally heterogeneous, most computer simulations of electrical activity take into account SAN pacemaker cells only. Our aim was to investigate how fibroblasts affect the SAN activity. We simulated the rabbit sinoatrial node accounting for differences between central and peripheral pacemaker cells, and for fibroblast‐myocyte electrical coupling. We have observed that only if fibroblast‐myocyte coupling is taken into account, (1) action potential is initiated in the central part of the SAN (within 1.2 mm of the center of simulated tissue); otherwise, leading centers are located on the periphery; (2) few (1 to 6) leading centers initiate action potential in the SAN; otherwise, we observed more than 8 leading centers; (3) acetylcholine superfusion results in a shift of leading centers toward the SAN periphery; and (4) sinus pauses up to 1.9 second follow acetylcholine superfusion. We observed negligible effect of fibroblast‐myocyte coupling on the period of SAN activation. We conclude that fibroblast‐myocyte coupling may explain action potential initiation and propagation from the center of the SAN observed in experimental studies, while atrial load on the peripheral SAN fails to explain this fact.
Detection of prohibited substances in equine hair by ultra‐high performance liquid chromatography–triple quadrupole mass spectrometry – application to doping control samples
Authors: Gray B. , Viljanto M. , Menzies E. , Vanhaecke L. 
Published: February 2018

AbstractThe detection of drugs in human hair samples has been performed by laboratories around the world for many years and the matrix is popular in disciplines, such as workplace drug testing. To date, however, hair has not become a routinely utilised matrix in sports drug detection. The analysis of hair samples offers several potential advantages to doping control laboratories, not least of which are the greatly extended detection window and the ease of sample collection and storage.This article describes the development, validation, and utilisation of a sensitive ultra‐high performance liquid chromatography–triple quadrupole mass spectrometry (UHPLC–MS/MS) method for the detection of 50 compounds. This provides significantly improved coverage for those analytes which would be of particular interest if detected in hair, such as anabolic steroid esters and selective androgen receptor modulators (SARMs).Qualitative validation of the method resulted in estimated limits of detection as low as 0.1 pg/mg for the majority of compounds, with all being detected at 2 pg/mg or below. The suitability of the method for the detection of prohibited substances in incurred material was demonstrated by the successful detection of several compounds, such as stanozolol, boldenone undecylenate, clenbuterol, and GW‐501516, in genuine equine hair samples. Estimated concentrations of the detected substances ranged from 0.27 to 8.6 pg/mg. The method has been shown to be fit‐for‐purpose for routine screening of equine hair samples by the analysis of over 400 genuine hair samples.
Quantification of rainfall interception in the high Andean tussock grasslands
Authors: Ochoa‐Sánchez A. , Crespo P. , Célleri R. 
Published: February 2018

AbstractThe páramo ecosystem provides most of the water for the tropical Andean highlands in South America. Although the comprehension of this environment has increased lately, there remains an urgent need to quantify the processes involved in the hydrological cycle. Interception loss (IL) is one of the least studied processes in the páramo, and more generally, in grasslands globally. The main objective of this study was to quantify IL at event scale by estimating it indirectly from precipitation (P) and effective rainfall (ER). Furthermore, the following questions were assessed: (a) how much of the P becomes ER? (b) what is the impact on IL calculations of using a rain gauge instead of a disdrometer? (c) which meteorological variables are related to the IL process? and (d) is it possible to estimate IL from meteorological variables? High percentages of IL in relation to P were found (10–100%). The canopy storage capacity of tussock grasses was approximately 2 mm. The disdrometer observations led to more accurate results than the rain gauge observations because only the disdrometer registers light precipitation, horizontal precipitation, and drizzle that increases the amount of P, ER, and IL estimates. Also, we found that IL is more strongly correlated with P; and IL can be estimated with a multiple linear regression (R2 = 0.9) from P and relative humidity for events where 1.7 < P < 8.5 mm. These findings show the important role of IL in the páramo and provide a stepping stone to modelling of water resources.
Human cardiomyocyte calcium handling and transverse tubules in mid‐stage of post‐myocardial‐infarction heart failure
Authors: Høydal Morten Andre , Kirkeby‐Garstad Idar , Karevold Asbjørn , Wiseth Rune , Haaverstad Rune , Wahba Alexander , Stølen Tomas L. , Contu Riccardo , Condorelli Gianluigi , Ellingsen Øyvind , Smith Godfrey L. , Kemi Ole J. , Wisløff Ulrik 
Published: February 2018

AbstractAimsCellular processes in the heart rely mainly on studies from experimental animal models or explanted hearts from patients with terminal end‐stage heart failure (HF). To address this limitation, we provide data on excitation contraction coupling, cardiomyocyte contraction and relaxation, and Ca2+ handling in post‐myocardial‐infarction (MI) patients at mid‐stage of HF.Methods and resultsNine MI patients and eight control patients without MI (non‐MI) were included. Biopsies were taken from the left ventricular myocardium and processed for further measurements with epifluorescence and confocal microscopy. Cardiomyocyte function was progressively impaired in MI cardiomyocytes compared with non‐MI cardiomyocytes when increasing electrical stimulation towards frequencies that simulate heart rates during physical activity (2 Hz); at 3 Hz, we observed almost total breakdown of function in MI. Concurrently, we observed impaired Ca2+ handling with more spontaneous Ca2+ release events, increased diastolic Ca2+, lower Ca2+ amplitude, and prolonged time to diastolic Ca2+ removal in MI (P < 0.01). Significantly reduced transverse‐tubule density (−35%, P < 0.01) and sarcoplasmic reticulum Ca2+ adenosine triphosphatase 2a (SERCA2a) function (−26%, P < 0.01) in MI cardiomyocytes may explain the findings. Reduced protein phosphorylation of phospholamban (PLB) serine‐16 and threonine‐17 in MI provides further mechanisms to the reduced function.ConclusionsDepressed cardiomyocyte contraction and relaxation were associated with impaired intracellular Ca2+ handling due to impaired SERCA2a activity caused by a combination of alteration in the PLB/SERCA2a ratio and chronic dephosphorylation of PLB as well as loss of transverse tubules, which disrupts normal intracellular Ca2+ homeostasis and handling. This is the first study that presents these mechanisms from viable and intact cardiomyocytes isolated from the left ventricle of human hearts at mid‐stage of post‐MI HF.
Controlling the Structures of Lanthanide Complexes in Self‐Assemblies with Tripodal Ligands
Authors: Hamacek Josef , Vuillamy Alexandra 
Published: February 2018

AbstractInvited for the cover of this issue is Josef Hamacek from CNRS Orléans, France. The cover image shows the spontaneous self‐assembly of tripodal ligands and lanthanide cations.
Real‐time Monitoring of Exocytotic Glutamate Release from Single Neuron by Amperometry at an Enzymatic Biosensor
Authors: Qiu Quan‐Fa , Zhang Fu‐Li , Tang Yun , Zhang Xin‐Wei , Jiang Hong , Liu Yan‐Ling , Huang Wei‐Hua 
Published: February 2018

AbstractGlutamate (Glu) is recognized as a vital neurotransmitter released via vesicular exocytosis and plays important roles in many physiological processes. Microelectrode amperometry has become a powerful method to study the secreted electroactive biochemicals via exocytosis, however, there was no means for direct monitoring of exocytosis of the non‐electroactive Glu so far. Herein, we developed an enzymatic micro‐biosensor by co‐modification of glutamate oxidase (GluOx) and Pt nanoparticles (Pt NPs) on the surface of a carbon fiber microelectrode. The Glu was enzymatically transformed by GluOx to an electroactive product, H2O2, which was then electrochemically detected by the Pt NPs. The prominent catalytic activity of enzyme and micrometer scale of microelectrode endow the sensor with high sensitivity and spatio‐temporal resolution, allowing real‐time monitoring Glu exocytosis from single hippocampal varicosities. The results demonstrate the capability of this biosensor in monitoring and quantification of the quantal release of neurotransmitter Glu, indicating its great potential in exploring the cellular mechanism of neuron communication and synaptic plasticity.
A meta‐analysis approach with filtering for identifying gene‐level gene–environment interactions
Authors: Wang Jiebiao , Liu Qianying , Pierce Brandon L. , Huo Dezheng , Olopade Olufunmilayo I. , Ahsan Habibul , Chen Lin S. 
Published: February 2018

ABSTRACTThere is a growing recognition that gene–environment interaction (G × E) plays a pivotal role in the development and progression of complex diseases. Despite a wealth of genetic data on various complex diseases/traits generated from association and sequencing studies, detecting G × E via genome‐wide analysis remains challenging due to power issues. In genome‐wide G × E studies, a common strategy to improve power is to first conduct a filtering test and retain only the genetic variants that pass the filtering step for subsequent G × E analyses. Two‐stage, multistage, and unified tests have been proposed to jointly consider the filtering statistics in G × E tests. However, such G × E tests based on data from a single study may still be underpowered. Meanwhile, large‐scale consortia have been formed to borrow strength across studies and populations. In this work, motivated by existing single‐study G × E tests with filtering and the needs for meta‐analysis G × E approaches based on consortia data, we propose a meta‐analysis framework for detecting gene‐based G × E effects, and introduce meta‐analysis‐based filtering statistics in the gene‐level G × E tests. Simulations demonstrate the advantages of the proposed method—the ofGEM test. We apply the proposed tests to existing data from two breast cancer consortia to identify the genes harboring genetic variants with age‐dependent penetrance (i.e., gene–age interaction effects). We develop an R software package ofGEM for the proposed meta‐analysis tests.
Manifold decoding for neural representations of face viewpoint and gaze direction using magnetoencephalographic data
Authors: Kuo Po‐Chih , Chen Yong‐Sheng , Chen Li‐Fen 
Published: February 2018

AbstractThe main challenge in decoding neural representations lies in linking neural activity to representational content or abstract concepts. The transformation from a neural‐based to a low‐dimensional representation may hold the key to encoding perceptual processes in the human brain. In this study, we developed a novel model by which to represent two changeable features of faces: face viewpoint and gaze direction. These features are embedded in spatiotemporal brain activity derived from magnetoencephalographic data. Our decoding results demonstrate that face viewpoint and gaze direction can be represented by manifold structures constructed from brain responses in the bilateral occipital face area and right superior temporal sulcus, respectively. Our results also show that the superposition of brain activity in the manifold space reveals the viewpoints of faces as well as directions of gazes as perceived by the subject. The proposed manifold representation model provides a novel opportunity to gain further insight into the processing of information in the human brain.
Modelling the dopamine and noradrenergic cell loss that occurs in Parkinson's disease and the impact on hippocampal neurogenesis
Authors: Ermine Charlotte M. , Wright Jordan L. , Frausin Stefano , Kauhausen Jessica A. , Parish Clare L. , Stanic Davor , Thompson Lachlan H. 
Published: February 2018

AbstractKey pathological features of Parkinson's Disease (PD) include the progressive degeneration of midbrain dopaminergic (DA) neurons and hindbrain noradrenergic (NA) neurons. The loss of DA neurons has been extensively studied and is the main cause of motor dysfunction. Importantly, however, there are a range of ‘non‐movement’ related features of PD including cognitive dysfunction, sleep disturbances and mood disorders. The origins for these non‐motor symptoms are less clear, but a possible substrate for cognitive decline may be reduced adult‐hippocampal neurogenesis, which is reported to be impaired in PD. The mechanisms underlying reduced neurogenesis in PD are not well established. Here we tested the hypothesis that NA and DA depletion, as occurs in PD, impairs hippocampal neurogenesis. We used 6‐hydroxydopamine or the immunotoxin dopamine‐β‐hydroxylase‐saporin to selectively lesion DA or NA neurons, respectively, in adult Sprague Dawley rats and assessed hippocampal neurogenesis through phenotyping of cells birth‐dated using 5‐bromo‐2′‐deoxyuridine. The results showed no difference in proliferation or differentiation of newborn cells in the subgranular zone of the dentate gyrus after NA or DA lesions. This suggests that impairment of hippocampal neurogenesis in PD likely results from mechanisms independent of, or in addition to degeneration of DA and NA neurons.
Differential contributions of Ca2+‐activated K+ channels and Na+/K+‐ATPases to the generation of the slow afterhyperpolarization in CA1 pyramidal cells
Authors: Tiwari Manindra Nath , Mohan Sandesh , Biala Yoav , Yaari Yoel 
Published: February 2018

AbstractIn many types of CNS neurons, repetitive spiking produces a slow afterhyperpolarization (sAHP), providing sustained, intrinsically generated negative feedback to neuronal excitation. Changes in the sAHP have been implicated in learning behaviors, in cognitive decline in aging, and in epileptogenesis. Despite its importance in brain function, the mechanisms generating the sAHP are still controversial. Here we have addressed the roles of M‐type K+ current (IM), Ca2+‐gated K+ currents (ICa(K)'s) and Na+/K+‐ATPases (NKAs) current to sAHP generation in adult rat CA1 pyramidal cells maintained at near‐physiological temperature (35 °C). No evidence for IM contribution to the sAHP was found in these neurons. Both ICa(K)'s and NKA current contributed to sAHP generation, the latter being the predominant generator of the sAHP, particularly when evoked with short trains of spikes. Of the different NKA isoenzymes, α1‐NKA played the key role, endowing the sAHP a steep voltage‐dependence. Thus normal and pathological changes in α1‐NKA expression or function may affect cognitive processes by modulating the inhibitory efficacy of the sAHP.
Nylon as an in vitro scaffold for three‐dimensional study of neural cells
Authors: Batth Aran , Thompson Ian 
Published: February 2018

AbstractThe requirement for improved modeling of cells in culture for study of cell‐to‐cell interactions has led to an increased focus on three‐dimensional (3D) in vitro models. In this study, NG108‐15 neural cells and rat sciatic nerve Schwann cells were successfully grown as monocultures and as a coculture on the biocompatible nylon mesh substrates. This has allowed proliferation and interactions between the two cell types to be monitored on the mesh over time. Electrophysiological recordings validated the NG108‐15 neural cell differentiation which confirmed the similarity of recorded action potentials in two‐dimensional culture environments. A variety of assays have been used, demonstrating the use of nylon as an appropriate substrate for neural cell in vitro studies, and nylon can easily be imaged using inverted microscopy. These studies confirm the suitability of the nylon 3D culture presented for modeling neural cell behavior. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1575–1584, 2018.