bluuebunny/crossref_metadata_2025_split huggingface dataset:
Helical Oligopeptides of a Quaternized Amino Acid with Tunable Chiral‐Induction Ability and an Anomalous pH Response
Authors: Cho Joonil , Ishida Yasuhiro , Aida Takuzo 
Published: February 2017

AbstractA series of octamer (8‐mer) and hexadecamer (16‐mer) oligopeptides of 4‐aminopiperidine‐4‐carboxylic acid (Api) with l‐leucine as a chiral auxiliary at their N or C termini were synthesized. By using circular dichroism spectroscopy, the conformational profiles of the peptides were systematically studied, which revealed that the α‐helix‐formation ability of the peptides is determined by the combination of parameters, which includes peptide length, state of the piperidine groups in the Api units, and position of the chiral auxiliary. When the piperidines were in the free‐base state, the peptides showed a low propensity to form helical structures. However, the protonation and acylation of the piperidines enhanced the formation of helical structures, such that the order for helix‐formation ability was protonated>acylated>free base. In terms of peptide length, the 16‐mers generally showed higher helix‐formation ability than the corresponding 8‐mers, and one of the 16‐mers showed helicity at the highest level reported thus far for oligopeptides of a similar length. It was also found that the sensitivity of the helical structure towards the state of the piperidine groups changed drastically depending on the chiral auxiliary position; the N‐terminal chiral peptides were more sensitive than the C‐terminal chiral analogues.
Enzymatic reuse of simulated dyeing process effluent using horseradish peroxidase
Authors: Farias Simone , Mayer Diego A. , de Oliveira Débora , de Souza Antônio Augusto Ulson , de Souza Selene M. A. Guelli U. 
Published: February 2017

AbstractReactive dyes are complex structures that cause environmental damage when discarded. The aim of this study was to evaluate the reuse of effluent from an enzyme‐catalyzed dyeing process. The main parameters that influence the degradation of the mixture of dyes using the enzyme horseradish peroxidase were studied using response surface methodology: enzyme, hydrogen peroxide, and dye concentrations as well as the pH. The best conditions for the synthetic effluent were then applied to the reuse of the effluent from the dyeing process in laboratory and pilot scales. In the studies in pilot scale a high colour intensity was obtained (ΔE* value of 0.6) and a good washing fastness (4.0). The results obtained indicate that peroxidases could be used for colour removal on an industrial scale to save water and energy in the post‐dyeing process, reusing part of this effluent with the same efficiency as that of a traditional process.
Micelles versus Ribbons: How Congeners Drive the Self‐Assembly of Acidic Sophorolipid Biosurfactants
Authors: Dhasaiyan Prabhu , Le Griel Patrick , Roelants Sophie , Redant Emile , Van Bogaert Inge N. A. , Prevost Sylvain , Prasad B. L. V. , Baccile Niki 
Published: February 2017

AbstractSophorolipids (SLs), a class of microbially derived biosurfactants, are reported by different research groups to have different self‐assembled structures (either micelles or giant ribbons) under the same conditions. Here we explore the reasons behind these contradictory results and attribute these differences to the role of specific congeners that are present in minute quantities. We show that a sample composed of a majority of oleic acid (C18:1) sophorolipid in the presence of only 0.5 % (or more) of congeners with stearic acid (C18:0) or linoleic acid (C18:2) results in the formation of micelles that are stable over long periods of time. Conversely, the presence of only 10 to 15 % of congeners with a stearic acid chain gives fibrillar structures instead of micelles. To study the mechanisms responsible, oleic acid SLs devoid of any other congeners were prepared. Very interestingly, this sample can self‐assemble into either micelles or fibers depending on minute modifications to the self‐assembly conditions. The findings are supported by light scattering, small‐angle X‐ray scattering, transmission electron microscopy under cryogenic conditions, high‐pressure liquid chromatography, and NMR spectroscopy.
Precipitation and Crystallization Kinetics in Silica Gardens
Authors: Glaab Fabian , Rieder Julian , Klein Regina , Choquesillo‐Lazarte Duane , Melero‐Garcia Emilio , García‐Ruiz Juan‐Manuel , Kunz Werner , Kellermeier Matthias 
Published: February 2017

AbstractThe front cover artwork is provided by the groups of Prof. Werner Kunz (University of Regensburg, Germany) and Prof. Juan Manuel García‐Ruiz (Laboratorio de Estudios Cristalográficos, CSIC‐UGR, Spain) as well as Dr. Matthias Kellermeier (BASF SE, Germany). The image shows silica gardens, a peculiar form of tubular precipitates that grow spontaneously in purely inorganic environments. In addition to their striking morphologies, these self‐assembled structures sustain drastic chemical gradients that drive a cascade of coupled diffusion and precipitation processes, which were studied by complementary synchrotron‐based techniques in the present work.Read the full text of the article at 10.1002/cphc.201600748.
Generation of an inducible mouse model to reversibly silence Stat3
Authors: Alorro Mariah G. , Pierce Thomas P. , Eissmann Moritz F. , Dijkstra Christine , Dickins Ross A. , Ernst Matthias , Buchert Michael , Masson Frederic 
Published: February 2017

AbstractSignal transducer and activator of transcription 3 (Stat3) is a transcription factor that has many essential roles during inflammation, development and cancer. Stat3 is therefore an attractive therapeutic target in many diseases. While current Stat3 knockout mouse models led to a better understanding of the role of Stat3, the irreversible nature of Stat3 ablation does not model the effects of transient Stat3 therapeutic inhibition, and does not inform on potential dosage effects of Stat3. Using RNAi technology, we have generated a new mouse model allowing the inducible and reversible silencing of Stat3 in vivo, which mirrors the effects of specific Stat3 therapeutic interference. We showed that upon Doxycycline‐mediated activation of the Stat3 short‐hairpin RNA, Stat3 expression was efficiently reduced by about 80% in multiple organs and cell types. Moreover, Stat3 reduction was sufficient to reduce tumor burden in a clinically‐validated mouse model of gastric cancer. Finally, we demonstrated that Stat3 silencing during embryonic development led to reduced birth rate without leading to complete embryonic lethality, in contrast to full Stat3 ablation. In conclusion, this new mouse model will be invaluable to understand the effects of Stat3 therapeutic interference and Stat3 dosage effects.
Methods to test the interactive effects of drought and plant invasion on ecosystem structure and function using complementary common garden and field experiments
Authors: Alba Christina , NeSmith Julienne E. , Fahey Catherine , Angelini Christine , Flory Stephen Luke 
Published: February 2017

AbstractAbiotic global change drivers affect ecosystem structure and function, but how they interact with biotic factors such as invasive plants is understudied. Such interactions may be additive, synergistic, or offsetting, and difficult to predict. We present methods to test the individual and interactive effects of drought and plant invasion on native ecosystems. We coupled a factorial common garden experiment containing resident communities exposed to drought (imposed with rainout shelters) and invasion with a field experiment where the invader was removed from sites spanning a natural soil moisture gradient. We detail treatments and their effects on abiotic conditions, including soil moisture, light, temperature, and humidity, which shape community and ecosystem responses. Ambient precipitation during the garden experiment exceeded historic norms despite severe drought in prior years. Soil moisture was 48% lower in drought than ambient plots, but the invader largely offset drought effects. Additionally, temperature and light were lower and humidity higher in invaded plots. Field sites spanned up to a 10‐fold range in soil moisture and up to a 2.5‐fold range in light availability. Invaded and resident vegetation did not differentially mediate soil moisture, unlike in the garden experiment. Herbicide effectively removed invaded and resident vegetation, with removal having site‐specific effects on soil moisture and light availability. However, light was generally higher in invader‐removal than control plots, whereas resident removal had less effect on light, similar to the garden experiment. Invasion mitigated a constellation of abiotic conditions associated with drought stress in the garden experiment. In the field, where other factors co‐varied, these patterns did not emerge. Still, neither experiment suggested that drought and invasion will have synergistic negative effects on ecosystems, although invasion can limit light availability. Coupling factorial garden experiments with field experiments across environmental gradients will be effective for predicting how multiple stressors interact in natural systems.
A parasite's modification of host behavior reduces predation on its host
Authors: Soghigian John , Valsdottir Linda R. , Livdahl Todd P. 
Published: February 2017

AbstractParasite modification of host behavior is common, and the literature is dominated by demonstrations of enhanced predation on parasitized prey resulting in transmission of parasites to their next host. We present a case in which predation on parasitized prey is reduced. Despite theoretical modeling suggesting that this phenomenon should be common, it has been reported in only a few host–parasite–predator systems. Using a system of gregarine endosymbionts in host mosquitoes, we designed experiments to compare the vulnerability of parasitized and unparasitized mosquito larvae to predation by obligate predatory mosquito larvae and then compared behavioral features known to change in the presence of predatory cues. We exposedAedes triseriatuslarvae to the parasiteAscogregarina barrettiand the predatorToxohrynchites rutilusand assessed larval mortality rate under each treatment condition. Further, we assessed behavioral differences in larvae due to infection and predation stimuli by recording larvae and scoring behaviors and positions within microcosms. Infection with gregarines reduced cohort mortality in the presence of the predator, but the parasite did not affect mortality alone. Further, infection by parasites altered behavior such that infected hosts thrashed less frequently than uninfected hosts and were found more frequently on or in a refuge within the microcosm. By reducing predation on their host, gregarines may be acting as mutualists in the presence of predation on their hosts. These results illustrate a higher‐order interaction, in which a relationship between a species pair (host–endosymbiont or predator–prey) is altered by the presence of a third species.
Winter behavior of bats and the progression of white‐nose syndrome in the southeastern United States
Authors: Bernard Riley F. , McCracken Gary F. 
Published: February 2017

AbstractUnderstanding the winter behavior of bats in temperate North America can provide insight into how bats react to perturbations caused by natural disturbances such as weather, human‐induced disturbances, or the introduction of disease. This study measured the activity patterns of bats outside of their hibernaculum and asked how this winter activity varied by time, temperature, bat species, body condition, and WNS status. Over the course of three winters (2011–2013), we collected acoustic data and captured bats outside of five hibernacula in Tennessee, United States. During this time, Pseudogymnoascus destructans, the causative agent of white‐nose syndrome, became established in hibernacula throughout the region, allowing us to track disease‐related changes in the winter behavior of ten bat species. We determined that bats in the southeastern United States were active during winter regardless of disease. We recorded activity outside of hibernacula at temperatures as low as −13°C. Although bat activity was best determined by a combination of variables, the strongest factor was mean daily temperature (R2 = .2879, F1,1450 = 586.2, p < .0001). Bats that left the hibernacula earlier in evening had lower body condition than those that left 2–4 hr after sunset (F7,932 = 7.225, p < .0001, Tukey HSD, p < .05). The number of daytime emergences from hibernacula, as determined via acoustic detection, increased the longer a site was P. destructans positive (F3,17 808 = 124.48, p < .0001, Tukey HSD, p < .05). Through the use of passive acoustic monitoring and monthly captures, we determined that winter activity was driven by both ambient temperature and the presence of P. destructans.
In vivo toxicity of nitroaromatics: A comprehensive quantitative structure–activity relationship study
Authors: Gooch Aminah , Sizochenko Natalia , Rasulev Bakhtiyor , Gorb Leonid , Leszczynski Jerzy 
Published: February 2017

Abstract

The toxicity data of 90 nitroaromatic compounds related to their 50% lethal dose concentration for rats (LD50) were analyzed to develop quantitative structure–activity relationship (QSAR) models. Quantum-chemically calculated descriptors together with molecular descriptors generated by DRAGON, PaDEL, and HiT-QSAR software were utilized to build QSAR models. Quality and validity of the models were determined by internal and external validation techniques. The results show that the toxicity of nitroaromatic compounds depends on various factors, such as the number of nitro-groups, the topological state, and the presence of certain structural fragments. The developed models based on the largest (to date) dataset of nitroaromatics in vivo toxicity showed a good predictive ability. The results provide important input that could be applied in a preliminary assessment of nitroaromatic compounds’ toxicity to mammals. Environ Toxicol Chem 2017;36:2227–2233. © 2017 SETAC
An adapted mindfulness intervention for people with dementia in care homes: feasibility pilot study
Authors: Churcher Clarke A. , Chan J.M.Y. , Stott J. , Royan L. , Spector A. 
Published: February 2017

ObjectiveDepression and anxiety are common in dementia. There is a need to develop effective psychosocial interventions. This study sought to develop a group‐based adapted mindfulness programme for people with mild to moderate dementia in care homes and to determine its feasibility and potential benefits.MethodsA manual for a 10‐session intervention was developed. Participants were randomly allocated to the intervention plus treatment as usual (n = 20) or treatment as usual (n = 11). Measures of mood, anxiety, quality of life, cognitive function, stress and mindfulness were administered at baseline and 1 week post‐intervention.ResultsThere was a significant improvement in quality of life in the intervention group compared to controls (p = 0.05). There were no significant changes in other outcomes.ConclusionsThe intervention was feasible in terms of recruitment, retention, attrition and acceptability and was associated with significant positive changes in quality of life. A fully powered randomised controlled trial is required. Copyright © 2017 John Wiley & Sons, Ltd.
Correlation between plasma levels of arginine and citrulline in preterm and full‐term neonates: Therapeutical implications
Authors: Contreras Mike T. , Gallardo Maria J. , Betancourt Luis R. , Rada Pedro V. , Ceballos Gerardo A. , Hernandez Luis E. , Hernandez Luis F. 
Published: February 2017

BackgroundPreterm neonates exhibit several deficiencies that endanger their lives. Understanding those disturbances will provide tools for the management of preterm neonates. The present work focuses on arginine and citrulline which has been flagged among the biochemical landmarks of prematurity.MethodsWe examined blood samples of preterm newborns as compared with mature neonates to determine the levels of arginine and citrulline by capillary zone electrophoresis with laser induced fluorescence detection (CZE‐LIFD).ResultsSignificantly lower levels of arginine and citrulline were found in preterm neonates than in mature neonates (P<.01). Interestingly there was a highly significant correlation between the two amino acids in mature neonates (P<.0001). Such correlation was present in preterm neonates too (P<.01). Pearson coefficient showed that 60% of the citrulline concentration depends on arginine concentration in mature neonates. Only 20% of the citrulline concentration depends on arginine concentration in preterm neonates. Although the ratio arginine/citrulline was lower in preterm neonates than in mature neonates the difference was not statistically significant.ConclusionsThese results suggest that less arginine is converted to citrulline to form nitric oxide in preterm than in full‐term neonates. The result is discussed in terms of the immature enzymatic systems in the preterm neonate.
Comparative study of dental enamel loss after debonding braces by analytical scanning electron microscopy (SEM)
Authors: Rodríguez‐Chávez Jacqueline Adelina , Arenas‐Alatorre Jesús , Belio‐Reyes Irma Araceli 
Published: February 2017

AbstractClinical procedures when shear forces are applied to brackets suggest adhesion forces between 2.8 and 10.0 MPa as appropriate. In this study dental enamel was evaluated by scanning electron microscopy (SEM) before and after removing the brackets. Thirty bicuspids (previous prophylaxis) with metallic brackets (Roth Inovation 0.022 GAC), Transbond Plus SEP 3M Unitek adhesive and Transbond XT 3M resin were used. The samples were preserved to 37°C during 24 hr and submited to tangential forces with the Instron Universal machine 1.0 mm/min speed load strength resistance debonding. Also the Adhesive Remanent Index (ARI) test was made, evaluating the bracket base and the bicuspid surface. All the bracket SEM images were processed with AutoCAD to determine the enamel detached area. The average value was 6.86 MPa (SD ± 3.2 MPa). ARI value 1= 63.3%, value 2= 20%, value 3= 13.3% and 33% presented value 0. All those samples with dental enamel loss, presented different situations as fractures, ledges, horizontal, and vertical loss in some cases, and some scratch lines. There is no association between the debonding resistance and enamel presence. Less than half of the remanent adhesive on the dental enamel was present in most of the samples when the ARI test was applied. When the resin area increases, the debonding resistance also increases, and when the enamel loss increases, the resin free metallic area of the bracket base decreases in the debonding.
Effects of acidic peptide size and sequence on trivalent praseodymium adduction and electron transfer dissociation mass spectrometry
Authors: Commodore Juliette J. , Cassady Carolyn J. 
Published: February 2017

Using the lanthanide ion praseodymium, Pr(III), metallated ion formation and electron transfer dissociation (ETD) were studied for 25 biological and model acidic peptides. For chain lengths of seven or more residues, even highly acidic peptides that can be difficult to protonate by electrospray ionization will metallate and undergo abundant ETD fragmentation. Peptides composed of predominantly acidic residues form only the deprotonated ion, [M + Pr ‐ H]2+; this ion yields near complete ETD sequence coverage for larger peptides. Peptides with a mixture of acidic and neutral residues generate [M + Pr]3+, which cleaves between every residue for many peptides. Acidic peptides that contain at least one residue with a basic side chain also produce the protonated ion, [M + Pr + H]4+; this ion undergoes the most extensive sequence coverage by ETD. Primarily metallated and non‐metallated c‐ and z‐ions form for all peptides investigated. Metal adducted product ions are only present when at least half of the peptide sequence can be incorporated into the ion; this suggests that the metal ion simultaneously attaches to more than one acidic site. The only site consistently lacking dissociation is at the N‐terminal side of a proline residue. Increasing peptide chain length generates more backbone cleavage for metal‐peptide complexes with the same charge state. For acidic peptides with the same length, increasing the precursor ion charge state from 2+ to 3+ also leads to more cleavage. The results of this study indicate that highly acidic peptides can be sequenced by ETD of complexes formed with Pr(III). Copyright © 2017 John Wiley & Sons, Ltd.
Targeted workplace incivility: The roles of belongingness, embarrassment, and power
Authors: Hershcovis M. Sandy , Ogunfowora Babatunde , Reich Tara C. , Christie Amy M. 
Published: February 2017

SummaryResearch to date has largely been unclear about whether a single perpetrator is sufficient to instigate the well‐documented negative consequences of workplace incivility. In the current research, we examine the extent to which perceived belongingness and embarrassment mediate the relationship between incivility from a single perpetrator and two important outcomes (job insecurity and somatic symptoms), and the extent to which the perpetrator's power moderates these relationships. Across two studies using different methods, we find that incidents of single perpetrator incivility are associated with target feelings of isolation and embarrassment, which in turn relate to targets' perceived job insecurity and somatic symptoms (Studies 1 and 2) both the same day and three days later (Study 2). Moreover, we find that perpetrator power moderates the relationship between incivility and embarrassment, such that targets are more embarrassed when the perpetrator is powerful. Implications for theory and practice are discussed. Copyright © 2017 John Wiley & Sons, Ltd.
Incidence and prognosis of non‐metastatic triple negative breast cancer (TNBC) among different races in Southeast Asia
Authors: Alcantara Veronica Siton , Lim Geok Hoon , Lim Swee Ho , Sultana Rehena , Lee Jung Ah 
Published: February 2017

BACKGROUND AND OBJECTIVESTriple negative breast cancer (TNBC) carries a worse prognosis compared to the other subtypes. There have been conflicting studies that race may impact the prognosis of TNBC patients. We aim to determine the incidence and prognosis of TNBC among the different ethnic races in Singapore, and to determine its associated risk factors for prognosis.METHODSPatients diagnosed with invasive breast cancer (BC) from 2005 to 2013 at our tertiary institution were included and divided according to race and subtypes. Demographic and clinical information of non‐metastatic TNBC patients were analyzed. Log‐rank test, univariate and multivariate Cox proportional hazard regression models were used to find associated risk factors related with overall survival (OS) and disease‐free survival (DFS).RESULTSAmong 1227 BC patients, 129 (10.5%) had TNBC. TNBC patients had the worst OS (P: 0.0005) and DFS (P: 0.0016) among the subtypes. However, variations in race did not have any difference in OS or DFS among TNBC patients. Axillary lymph node involvement, invasive lobular histology, larger tumor size, and the presence of lymphovascular invasion (LVI) were factors associated with both poor DFS and OS among TNBC patients.CONCLUSIONSRacial variation did not have any impact on the prognosis of the TNBC.