bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular dynamics study of ferroelectric domain nucleation and domain switching dynamics
Authors: Boddu Vishal , Endres Florian , Steinmann Paul 
Published: April 2017

AbstractFerroelectric materials contain domains of ordered electric dipoles, separated by domain walls, that can undergo polarisation switching under externally applied electric fields. The domain switching dynamics in ferroelectric materials plays an essential role in their application to electronic and electro-optic de- vices. Previous studies suggest that the switching occurs largely through domain wall motion which is explained from the viewpoint of statistical physics on surface growth as the behaviour of a pinned elas- tic interface. We perform molecular dynamics simulations to investigate the domain switching process and quantitatively estimate the switching speed of anti-parallel 180° domains in ferroelectric, tetragonal BaTiO3 perfect single crystals at room temperature using the core-shell model. We observe an unprece- dented, non-linear increase in the domain switching speed caused by the nucleation of new domains within the switching domain. We determine the strength of the electric field to evoke nucleation of new domains and show that the nucleated domains diffuse into nearby favourable domains when the electric field is removed. Furthermore, we discuss the prominence of domain nucleations during ferroelectric switching.
Computationally Discovered Potentiating Role of Glycans on NMDA Receptors
Authors: Sinitskiy Anton V. , Stanley Nathaniel H. , Hackos David H. , Hanson Jesse E. , Sellers Benjamin D. , Pande Vijay S. 
Published: April 2017

AbstractN-methyl-D-aspartate receptors (NMDARs) are glycoproteins in the brain central to learning and memory. The effects of glycosylation on the structure and dynamics of NMDARs are largely unknown. In this work, we use extensive molecular dynamics simulations of GluN1 and GluN2B ligand binding domains (LBDs) of NMDARs to investigate these effects. Our simulations predict that intra-domain interactions involving the glycan attached to residue GluN1-N440 stabilize closed-clamshell conformations of the GluN1 LBD. The glycan on GluN2B-N688 shows a similar, though weaker, effect. Based on these results, and assuming the transferability of the results of LBD simulations to the full receptor, we predict that glycans at GluN1-N440 might play a potentiator role in NMDARs. To validate this prediction, we perform electrophysiological analysis of full-length NMDARs with a glycosylation-preventing GluN1-N440Q mutation, and demonstrate an increase in the glycine EC50 value. Overall, our results suggest an intramolecular potentiating role of glycans on NMDA receptors.
Siglec-7 restores β-cell function and survival and reduces inflammation in pancreatic islets from patients with diabetes
Authors: Dharmadhikari Gitanjali , Stolz Katharina , Hauke Michael , Morgan Noel G. , Varki Ajit , de Koning Eelco , Kelm Sørge , Maedler Kathrin 
Published: April 2017

AbstractChronic inflammation plays a key role in both type 1 and type 2 diabetes. Cytokine and chemokine production within the islets in a diabetic milieu results in β-cell failure and diabetes progression. Identification of targets, which both prevent macrophage activation and infiltration into islets and restore β-cell functionality is essential for effective diabetes therapy. We report that certain Sialic-acid-binding immunoglobulin-like-lectins (siglecs) are expressed in human pancreatic islets in a cell-type specific manner. Siglec-7 was expressed on β-cells and down-regulated in type 1 and type 2 diabetes and in infiltrating activated immune cells. Over-expression of Siglec-7 in diabetic islets reduced cytokines, prevented β-cell dysfunction and apoptosis and reduced recruiting of migrating monocytes. Our data suggest that restoration of human Siglec-7 expression may be a novel therapeutic strategy targeted to both inhibition of immune activation and preservation of β-cell function and survival.
A Fluorometric Method of Measuring Carboxypeptidase Activities for Angiotensin II and Apelin-13
Authors: Liu Pan , Wysocki Jan , Serfozo Peter , Ye Minghao , Souma Tomokazu , Batlle Daniel , Jin Jing 
Published: April 2017

AbstractDegradation of the biologically potent octapeptide angiotensin Ang II-(1-8) is mediated by the activities of several peptidases. The conversion of Ang II to the septapeptide Ang-(1-7) is of particular interest as the latter also confers organ protection. The conversion is catalyzed by angiotensin-converting enzyme 2 and other enzymes that selectively cleave the peptide bond between the proline and the phenylalanine at the carboxyl terminus of Ang II. The contribution of various enzyme activities that collectively lead to the formation of Ang-(1-7) from Ang II, in both normal conditions and in disease states, remains only partially understood. This is largely due to the lack of a reliable and sensitive method to detect these converting activities in complex samples, such as blood and tissues. Here, we report a fluorometric method to measure carboxypeptidase activities that cleave the proline-phenylalanine dipeptide bond in Ang II. This method is also suitable for measuring the conversion of apelin-13. The assay detects the release of phenylalanine amino acid in a reaction with the yeast enzyme of phenylalanine ammonia lyase (PAL). When used in cell and mouse organs, the assay can robustly measure endogenous Ang II and apelin-13-converting activities involved in the renin-angiotensin and the apelinergic systems, respectively.
Visual crowding is a combination of an increase of positional uncertainty, source confusion, and featural averaging
Authors: Harrison William J. , Bex Peter J. 
Published: April 2017

AbstractAlthough we perceive a richly detailed visual world, our ability to identify individual objects is severely limited in clutter, particularly in peripheral vision. Models of such “crowding” have generally been driven by the phenomenological misidentifications of crowded targets: using stimuli that do not easily combine to form a unique symbol (e.g. letters or objects), observers typically confuse the source of objects and report either the target or a distractor, but when continuous features are used (e.g. orientated gratings or line positions) observers report a feature somewhere between the target and distractor. To reconcile these accounts, we develop a hybrid method of adjustment that allows detailed analysis of these multiple error categories. Observers reported the orientation of a target, under several distractor conditions, by adjusting an identical foveal target. We apply new modelling to quantify whether perceptual reports show evidence of positional uncertainty, source confusion, and featural averaging on a trial-by-trial basis. Our results show that observers make a large proportion of source-confusion errors. However, our study also reveals the distribution of perceptual reports that underlie performance in this crowding task more generally: aggregate errors cannot be neatly labelled because they are heterogeneous and their structure depends on target-distractor distance.
HPV positive neuroendocrine cervical cancer cells are dependent on Myc but not E6/E7 viral oncogenes
Authors: Yuan Hang , Krawczyk Ewa , Blancato Jan , Albanese Christopher , Zhou Dan , Wang Naidong , Paul Siddartha , Alkhilaiwi Faris , Palechor-Ceron Nancy , Dakic Aleksandra , Fang Shuang , Choudhary Sujata , Hou Tung-Wei , Zheng Yun-Ling , Haddad Bassem R. , Usuda Yukari , Hartmann Dan , Symer David , Gillison Maura , Agarwal Seema , Wangsa Danny , Ried Thomas , Liu Xuefeng , Schlegel Richard 
Published: April 2017

AbstractUsing conditional cell reprogramming, we generated a stable cell culture of an extremely rare and aggressive neuroendocrine cervical cancer. The cultured cells contained HPV-16, formed colonies in soft agar and rapidly produced tumors in immunodeficient mice. The HPV-16 genome was integrated adjacent to the Myc gene, both of which were amplified 40-fold. Analysis of RNA transcripts detected fusion of the HPV/Myc genes, arising from apparent microhomologous recombination. Spectral karyotyping (SKY) and fluorescent-in-situ hybridization (FISH) demonstrated coordinate localization and translocation of the amplified Myc and HPV genes on chromosomes 8 and 21. Similar to the primary tumor, tumor cell cultures expressed very high levels of the Myc protein and, in contrast to all other HPV-positive cervical cancer cell lines, they harbored a gain-of-function mutation in p53 (R273C). Unexpectedly, viral oncogene knockdown had no effect on the growth of the cells, but it did inhibit the proliferation of a conventional HPV-16 positive cervical cancer cell line. Knockdown of Myc, but not the mutant p53, significantly inhibited tumor cell proliferation. On the basis of these data, we propose that the primary driver of transformation in this aggressive cervical cancer is not HPV oncogene expression but rather the overexpression of Myc.
Carbon dioxide induced plasticity of branchial acid-base pathways in an estuarine teleost
Authors: Allmon Elizabeth B. , Esbaugh Andrew J. 
Published: April 2017

AbstractAnthropogenic CO2 is expected to drive ocean pCO2 above 1,000 μatm by 2100 – inducing respiratory acidosis in fish that must be corrected through branchial ion transport. This study examined the time course and plasticity of branchial metabolic compensation in response to varying levels of CO2 in an estuarine fish, the red drum, which regularly encounters elevated CO2 and may therefore have intrinsic resilience. Under control conditions fish exhibited net base excretion; however, CO2 exposure resulted in a dose dependent increase in acid excretion during the initial 2 h. This returned to baseline levels during the second 2 h interval for exposures up to 5,000 μatm, but remained elevated for exposures above 15,000 μatm. Plasticity was assessed via gene expression in three CO2 treatments: environmentally realistic 1,000 and 6,000 μatm exposures, and a proof-of-principle 30,000 μatm exposure. Few differences were observed at 1,000 or 6,000 μatm; however, 30,000 μatm stimulated widespread up-regulation. Translocation of V-type ATPase after 1 h of exposure to 30,000 μatm was also assessed; however, no evidence of translocation was found. These results indicate that red drum can quickly compensate to environmentally relevant acid-base disturbances using baseline cellular machinery, yet are capable of plasticity in response to extreme acid-base challenges.
Prediction of oxygen uptake dynamics by machine learning analysis of wearable sensors during activities of daily living
Authors: Beltrame T. , Amelard R. , Wong A. , Hughson R. L. 
Published: April 2017

AbstractCurrently, oxygen uptake ("Equation missing") is the most precise means of investigating aerobic fitness and level of physical activity; however, "Equation missing" can only be directly measured in supervised conditions. With the advancement of new wearable sensor technologies and data processing approaches, it is possible to accurately infer work rate and predict "Equation missing" during activities of daily living (ADL). The main objective of this study was to develop and verify the methods required to predict and investigate the "Equation missing" dynamics during ADL. The variables derived from the wearable sensors were used to create a "Equation missing" predictor based on a random forest method. The "Equation missing" temporal dynamics were assessed by the mean normalized gain amplitude (MNG) obtained from frequency domain analysis. The MNG provides a means to assess aerobic fitness. The predicted "Equation missing" during ADL was strongly correlated (r = 0.87, P < 0.001) with the measured "Equation missing" and the prediction bias was 0.2 ml·min−1·kg−1. The MNG calculated based on predicted "Equation missing" was strongly correlated (r = 0.71, P < 0.001) with MNG calculated based on measured "Equation missing" data. This new technology provides an important advance in ambulatory and continuous assessment of aerobic fitness with potential for future applications such as the early detection of deterioration of physical health.
Effects of a warm compress containing menthol on the tear film in healthy subjects and dry eye patients
Authors: Arita Reiko , Morishige Naoyuki , Sakamoto Ichiro , Imai Natsuko , Shimada Yuko , Igaki Michihito , Suzuki Atsushi , Itoh Kouzo , Tsubota Kazuo 
Published: April 2017

AbstractMenthol is thought to stimulate lacrimation via activation of cold-sensitive primary afferent neurons in the cornea. We evaluated a warm compress containing menthol as a potential treatment for dry eye by examining its effects on the tear film in healthy subjects (n = 20) and dry eye patients (n = 35). Disposable eyelid-warming steamers that either did (MH) or did not (HO) contain menthol were applied to one eye of each subject either once only for 10 min or repeatedly over 2 weeks. Single application of MH significantly increased tear meniscus volume (P = 8.6 × 10−5, P = 1.3 × 10−5) and tear film breakup time (P = 0.006, P = 0.002) as well as improved meibum condition in healthy subjects and dry eye patients, respectively. Repeated application of MH significantly increased tear meniscus volume (P = 0.004, P = 1.7 × 10−4) and tear film breakup time (P = 0.037, P = 0.010) in healthy subjects and dry eye patients, respectively. Repeated application of MH thus induced persistent increases in tear fluid volume and tear film stability in dry eye patients, suggesting that repeated use of a warm compress containing menthol is a potential novel treatment for dry eye disease.
Offshore exposure experiments on cuttlefish indicate received sound pressure and particle motion levels associated with acoustic trauma
Authors: Solé Marta , Sigray Peter , Lenoir Marc , van der Schaar Mike , Lalander Emilia , André Michel 
Published: April 2017

AbstractRecent findings on cephalopods in laboratory conditions showed that exposure to artificial noise had a direct consequence on the statocyst, sensory organs, which are responsible for their equilibrium and movements in the water column. The question remained about the contribution of the consequent near-field particle motion influence from the tank walls, to the triggering of the trauma. Offshore noise controlled exposure experiments (CEE) on common cuttlefish (Sepia officinalis), were conducted at three different depths and distances from the source and particle motion and sound pressure measurements were performed at each location. Scanning electron microscopy (SEM) revealed injuries in statocysts, which severity was quantified and found to be proportional to the distance to the transducer. These findings are the first evidence of cephalopods sensitivity to anthropogenic noise sources in their natural habitat. From the measured received power spectrum of the sweep, it was possible to determine that the animals were exposed at levels ranging from 139 to 142 dB re 1 μPa2 and from 139 to 141 dB re 1 μPa2, at 1/3 octave bands centred at 315 Hz and 400 Hz, respectively. These results could therefore be considered a coherent threshold estimation of noise levels that can trigger acoustic trauma in cephalopods.
Brief intervention to promote smoking cessation and improve glycemic control in smokers with type 2 diabetes: a randomized controlled trial
Authors: Li William H. C. , Wang M. P. , LAM T. H. , Cheung Yannes T. Y. , Cheung Derek Y. T. , Suen Y. N. , Ho K. Y. , Tan Kathryn C. B. , CHAN Sophia S. C. 
Published: April 2017

AbstractThe aim of the study was to examine the effects of a brief stage-matched smoking cessation intervention group compared with a control group (with usual care) in type 2 diabetes mellitus patients who smoked by randomized controlled trial. There were 557 patients, randomized either into the intervention group (n = 283) who received brief (20- minute) individualized face-to-face counseling by trained nurses and a diabetes mellitus-specific leaflet, or a control group (n = 274) who received standard care. Patient follow-ups were at 1 week, 1 month, 3 months, 6 months, and 12 months via telephone, and assessment of smoking status from 2012 to 2014. Patients smoked an average of 14 cigarettes per day for more than 37 years, and more than 70% were in the precontemplation stage of quitting. The primary outcome showed that both the intervention and control groups had similar 7-day point-prevalence smoking abstinence (9.2% vs. 13.9%; p = 0.08). The secondary outcome showed that HbA1c levels with 7.95% [63 mmol/mol] vs. 8.05% [64 mmol/mol], p = 0.49 at 12 months, respectively. There was no evidence for effectiveness in promoting the brief stage-matched smoking cessation or improving glycemic control in smokers with type 2 diabetes mellitus, particularly those in the pre-contemplation stage.
Real-time tracking the Li+-ion transition behavior and dynamics in solid Poly(vinyl alcohol)/LiClO4 electrolytes
Authors: Bao Lixia , Zou Xin , Luo Xin , Pu Yanlei , Wang Jiliang , Lei Jingxin 
Published: April 2017

AbstractTo delicately track the Li-ion transport in SPEs under an external electric field (EF) is a big challenge, considering the limitation of most spectroscopic methods to monitor the real-time conformational changes and track the dynamic process. Herein, real-time Li-ion transition behavior and transport dynamics in typical poly(vinyl alcohol)/LiClO4 electrolytes under an external EF have been studied by combining time-resolved Fourier transform infrared (FTIR) with two-dimensional correlation FTIR spectroscopy. Results show that no migration of Li-ions has been detected when the time scale of the EF loading is at nanosecond (less than 200 ns). However, for the first time, Li-ions have been found to significantly transfer along the EF direction as the time scale enhances to microsecond order of magnitude and the migration period is less than 10 microseconds. The Li+ migration in the SPEs under an EF is a complicated process including quasi-periodic dissociation and coordination effects between Li-ion carriers and polymeric chains.
Involvement of galanin and galanin receptor 2 in nociceptive modulation in anterior cingulate cortex of normal rats and rats with mononeuropathy
Authors: Zhang Meng-Lin , Wang Hong-Bo , Fu Feng-Hua , Yu Long-Chuan 
Published: April 2017

AbstractThe present study was performed to explore the role of galanin and galanin receptor 2 in nociceptive modulation in anterior cingulate cortex (ACC) of normal rats and rats with mononeuropathy. Intra-ACC injection of galanin induced significant increases in hindpaw withdrawal latencies (HWLs) to thermal and mechanical stimulations in both normal rats and rats with mononeuropathy, the increased HWLs were attenuated significantly by intra-ACC injection of galanin receptor 2 antagonist M871, indicating an involvement of galanin receptor 2 in nociceptive modulation in ACC. Interestingly, the galanin-induced HWL was significant higher in rats with mononeuropathy than that in normal rats tested by Randall Selitto test. Furthermore, both the galanin mRNA expression and galanin content increased significantly in ACC in rats with mononeuropathy than that in normal rats. Moreover, both the mRNA levels of galanin receptor 2 and the content of galanin receptor 2 in ACC increased significantly in rats with mononeuropathy than that in normal rats. These results found that galanin induced antinociception in ACC in both normal rats and rats with mononeuropathy. And there may be plastic changes in the expression of galanin and galanin receptor 2 in rats with mononeuropathy, as well as in the galanin-induced antinociception.
Identification and expression analyses of the alanine aminotransferase (AlaAT) gene family in poplar seedlings
Authors: Xu Zhiru , Ma Jing , Qu Chunpu , Hu Yanbo , Hao Bingqing , Sun Yan , Liu Zhongye , Yang Han , Yang Chengjun , Wang Hongwei , Li Ying , Liu Guanjun 
Published: April 2017

AbstractAlanine aminotransferase (AlaAT, E.C.2.6.1.2) catalyzes the reversible conversion of pyruvate and glutamate to alanine and α-oxoglutarate. The AlaAT gene family has been well studied in some herbaceous plants, but has not been well characterized in woody plants. In this study, we identified four alanine aminotransferase homologues in Populus trichocarpa, which could be classified into two subgroups, A and B. AlaAT3 and AlaAT4 in subgroup A encode AlaAT, while AlaAT1 and AlaAT2 in subgroup B encode glutamate:glyoxylate aminotransferase (GGAT), which catalyzes the reaction of glutamate and glyoxylate to α-oxoglutarate and glycine. Four AlaAT genes were cloned from P. simonii × P. nigra. PnAlaAT1 and PnAlaAT2 were expressed predominantly in leaves and induced by exogenous nitrogen and exhibited a diurnal fluctuation in leaves, but was inhibited in roots. PnAlaAT3 and PnAlaAT4 were mainly expressed in roots, stems and leaves, and was induced by exogenous nitrogen. The expression of PnAlaAT3 gene could be regulated by glutamine or its related metabolites in roots. Our results suggest that PnAlaAT3 gene may play an important role in nitrogen metabolism and is regulated by glutamine or its related metabolites in the roots of P. simonii × P. nigra.
Aipl1 is required for cone photoreceptor function and survival through the stability of Pde6c and Gc3 in zebrafish
Authors: Iribarne Maria , Nishiwaki Yuko , Nakamura Shohei , Araragi Masato , Oguri Eri , Masai Ichiro 
Published: April 2017

AbstractGenetic mutations in aryl hydrocarbon receptor interacting protein-like 1 (AIPL1) cause photoreceptor degeneration associated with Leber congenital amaurosis 4 (LCA4) in human patients. Here we report retinal phenotypes of a zebrafish aipl1 mutant, gold rush (gosh). In zebrafish, there are two aipl1 genes, aipl1a and aipl1b, which are expressed mainly in rods and cones, respectively. The gosh mutant gene encodes cone-specific aipl1, aipl1b. Cone photoreceptors undergo progressive degeneration in the gosh mutant, indicating that aipl1b is required for cone survival. Furthermore, the cone-specific subunit of cGMP phosphodiesterase 6 (Pde6c) is markedly decreased in the gosh mutant, and the gosh mutation genetically interacts with zebrafish pde6c mutation eclipse (els). These data suggest that Aipl1 is required for Pde6c stability and function. In addition to Pde6c, we found that zebrafish cone-specific guanylate cyclase, zGc3, is also decreased in the gosh and els mutants. Furthermore, zGc3 knockdown embryos showed a marked reduction in Pde6c. These observations illustrate the interdependence of cGMP metabolism regulators between Aipl1, Pde6c, and Gc3 in photoreceptors.