bluuebunny/crossref_metadata_2025_split huggingface dataset:
Attention modulates topology and dynamics of auditory sensory gating
Authors: Golubic Sanja Josef , Jurasic Miljenka Jelena , Susac Ana , Huonker Ralph , Gotz Theresa , Haueisen Jens 
Published: March 2019

AbstractThis work challenges the widely accepted model of sensory gating as a preattention inhibitory process by investigating whether attention directed at the second tone (S2) within a paired‐click paradigm could affect gating at the cortical level. We utilized magnetoencephalography, magnetic resonance imaging and spatio‐temporal source localization to compare the cortical dynamics underlying gating responses across two conditions (passive and attention) in 19 healthy subjects. Source localization results reaffirmed the existence of a fast processing pathway between the prefrontal cortex (PFC) and bilateral superior temporal gyri (STG) that underlies the auditory gating process. STG source dynamics comprised two gating sub‐components, Mb1 and Mb2, both of which showed significant gating suppression (>51%). The attention directed to the S2 tone changed the gating network topology by switching the prefrontal generator from a dorsolateral location, which was active in the passive condition (18/19), to a medial location, active in the attention condition (19/19). Enhanced responses to the attended stimulus caused a significant reduction in gating suppression in both STG gating components (>50%). Our results demonstrate that attention not only modulates sensory gating dynamics, but also exerts topological rerouting of information processing within the PFC. The present data, suggesting that the cortical levels of early sensory processing are subject to top‐down influences, change the current view of gating as a purely automatic bottom‐up process.
Silence of long noncoding RNA NEAT1 exerts suppressive effects on immunity during sepsis by promoting microRNA‐125‐dependent MCEMP1 downregulation
Authors: Chen Jian‐Xin , Xu Xiong , Zhang Sen 
Published: March 2019

AbstractAccumulating studies have recognized microRNAs (miRs) and long noncoding RNAs (lncRNAs) as important molecules involved in the mediation of various biological processes, including innate immunity. In this study, we investigated a novel noncoding RNA regulatory circuitry in the immunity during sepsis. A cecal ligation and puncture‐induced sepsis mouse model was established to determine the expression of mast cell expression membrane protein 1 (MCEMP1). The RNA crosstalk among lncRNA nuclear enriched abundant transcript 1 (NEAT1), miR‐125, and MCEMP1 was validated. Subsequently, the levels of lncRNA NEAT1, miR‐125, and MCEMP1 in T lymphocytes isolated from sepsis mice were up‐ or downregulated by exogenous transfection in an attempt to investigate their effects on the release of inflammatory factors, the expression of immunoglobulins, the activity of T cell subsets and natural killer (NK) cells, as well as T lymphocyte apoptosis. In sepsis mice, MCEMP1 was highly expressed and verified to be a target gene of miR‐125. RNA crosstalk experiment revealed that lncRNA NEAT1 directly inhibited miR‐125 to upregulate MCEMP1. We also observed that elevation of miR‐125, depletion of MCEMP1, or downregulation of lncRNA NEAT1 resulted in promoted T lymphocyte activity, immunoglobulin expression, and NK cell activity, and inhibited release of inflammatory factors and T lymphocyte apoptosis. Taken together, these findings provided evidence that the downregulation of lncRNA NEAT1 could promote miR‐125 to exert an inhibitory effect on the immunity in septic mice by suppressing MCEMP1, highlighting a potential target for the treatment of sepsis. © 2019 IUBMB Life, 2019
A Metabolic Screen in Adolescents Reveals an Association Between Circulating Citrate and Cortical Bone Mineral Density
Authors: Kemp John P , Sayers Adrian , Fraser William D , Davey Smith George , Ala-Korpela Mika , Evans David M , Tobias Jonathan H 
Published: March 2019

ABSTRACT

Observations that insulin and adiponectin levels are related to cortical bone size in adolescents, independently of body composition, suggest factors related to fat metabolism directly influence skeletal development. To explore this question, we examined associations between a metabolic screen focusing on fat metabolism, and peripheral quantitative computed tomography (pQCT) measures of the mid-tibia, in 15-year-olds from the Avon Longitudinal Study of Parents and Children. Metabolic profiles were generated by proton nuclear magnetic resonance spectroscopy, from blood samples obtained at the same time as pQCT scans. Ordinary least squares linear regression was used to investigate relationships between metabolic measures and periosteal circumference (PC), cortical thickness (CT), and cortical bone mineral density (BMDC). Metabolic profiles yielded 22 independent components following principal component analysis (PCA), giving a Bonferroni-adjusted threshold for statistical significance of p = 0.002. Data were available in 1121 subjects (487 males), mean age 15 years. Several metabolites related to lipid and cholesterol metabolism were associated with PC, CT, and BMDC after adjustment for age, sex, and Tanner stage. After additional adjustment for height, fat, and lean mass, only the association between citrate and BMDC remained below the Bonferroni-significant threshold (β = –0.14 [–0.18, –0.09]) (β represents a standardized coefficient). Citrate also showed evidence of association with PC (β = 0.06 [0.03, 0.10]) and strength strain index (SSI; β = 0.04 [0.01, 0.08]). Subsequently, we investigated whether these relationships were explained by increased bone resorption. Citrate was strongly related to serum β-C-telopeptides of type I collagen (β-CTX) (β = 0.20 [0.16, 0.23]). After additional adjustment for β-CTX the above associations between citrate and BMDC (β = –0.04 [–0.08, 0.01]), PC (β = 0.03 [–0.01, 0.07]) and SSI (β = 0.03 [–0.01, 0.07]) were no longer observed. We conclude that in adolescents, circulating levels of citrate are inversely related to BMDC and positively related to PC, reflecting associations with higher bone turnover. Further studies are justified to elucidate possible contributions of citrate, a constituent of bone matrix, to bone resorption and cortical density. © 2019 American Society for Bone and Mineral Research.
A Novel Osteogenic Cell Line That Differentiates Into GFP-Tagged Osteocytes and Forms Mineral With a Bone-Like Lacunocanalicular Structure
Authors: Wang Kun , Le Lisa , Chun Brad M , Tiede-Lewis LeAnn M , Shiflett Lora A , Prideaux Matthew , Campos Richard S , Veno Patricia A , Xie Yixia , Dusevich Vladimir , Bonewald Lynda F , Dallas Sarah L 
Published: March 2019

ABSTRACT
Osteocytes, the most abundant cells in bone, were once thought to be inactive, but are now known to have multifunctional roles in bone, including in mechanotransduction, regulation of osteoblast and osteoclast function and phosphate homeostasis. Because osteocytes are embedded in a mineralized matrix and are challenging to study, there is a need for new tools and cell models to understand their biology. We have generated two clonal osteogenic cell lines, OmGFP66 and OmGFP10, by immortalization of primary bone cells from mice expressing a membrane-targeted GFP driven by the Dmp1-promoter. One of these clones, OmGFP66, has unique properties compared with previous osteogenic and osteocyte cell models and forms 3-dimensional mineralized bone-like structures, containing highly dendritic GFP-positive osteocytes, embedded in clearly defined lacunae. Confocal and electron microscopy showed that structurally and morphologically, these bone-like structures resemble bone in vivo, even mimicking the lacunocanalicular ultrastructure and 3D spacing of in vivo osteocytes. In osteogenic conditions, OmGFP66 cells express alkaline phosphatase (ALP), produce a mineralized type I collagen matrix, and constitutively express the early osteocyte marker, E11/gp38. With differentiation they express osteocyte markers, Dmp1, Phex, Mepe, Fgf23, and the mature osteocyte marker, Sost. They also express RankL, Opg, and Hif1α, and show expected osteocyte responses to PTH, including downregulation of Sost, Dmp1, and Opg and upregulation of RankL and E11/gp38. Live cell imaging revealed the dynamic process by which OmGFP66 bone-like structures form, the motile properties of embedding osteocytes and the integration of osteocyte differentiation with mineralization. The OmGFP10 clone showed an osteocyte gene expression profile similar to OmGFP66, but formed less organized bone nodule-like mineral, similar to other osteogenic cell models. Not only do these cell lines provide useful new tools for mechanistic and dynamic studies of osteocyte differentiation, function, and biomineralization, but OmGFP66 cells have the unique property of modeling osteocytes in their natural bone microenvironment. © 2019 American Society for Bone and Mineral Research
Size‐dependent antibacterial activity for laser‐generated silver nanoparticles
Authors: Korshed Peri , Li Lin , Liu Zhu , Mironov Aleksandr , Wang Tao 
Published: March 2019

AbstractSilver nanoparticles (Ag NPs) have been used widely for antibacterial applications; however, the effects of their sizes on antibacterial activities and toxicities to human cells, particularly for the laser‐generated Ag NPs, are not fully understood. In this study, sucrose gradient centrifugation was used to separate laser‐generated Ag NPs into different fractions by size. Transmission electron microscopy was used to analyze the size distribution of the Ag NPs, and well diffusion method was used to evaluate the antibacterial activity of the Ag NP fractions against the Escherichia coli. Results showed that the antibacterial effects of laser‐generated Ag NPs inversely correlated to the particle size. Among Ag NP fractions with average sizes ranging 19–47 nm, the 19‐nm Ag NPs presented the highest bactericidal effect. The smaller sized laser Ag NPs also significantly induced the generation of reactive oxygen species when applied to E. coli, compared with that of the larger sized laser Ag NPs. Cytotoxicity analysis revealed that the different sized laser‐generated Ag NPs were not significantly toxic to the human fibroblasts and lung epithelial cells in a 72‐h in vitro cell culture period. Understanding the size‐dependent functional properties of the laser‐generated Ag NPs helps informing the designs for future applications of the laser‐generated Ag NPs.
An efficient solution for resolving iTRAQ and TMT channel cross‐talk
Authors: Searle Brian C. , Yergey Alfred L. 
Published: March 2019

AbstractIsobaric tagging reagents such as isobaric tag for relative and absolute quantitation (iTRAQ) and tandem mass tag (TMT) typically have isotopic impurities that cause significant cross‐talk between channels. Here, we present an efficient solution to compensate for channel cross‐talk using linear algebra and find that it is between 20× and 120× faster than previous methods. We also find that the effects of channel cross‐talk are as important to manage as the effects of ratio compression because of precursor impurities, and we have released an open‐source tool to perform both types of calculations.
Multi‐millennial scale climate variability during MIS 3 and MIS 2 inferred from luminescence dating of coastal sand dunes and buried paleosol sequences in central Chile, 32°S
Authors: García Juan‐Luis , Andrade Belisario , Calderón Mauricio , Lüthgens Christopher 
Published: March 2019

ABSTRACTThe eolian morphostratigraphic archive along the coast of central Chile (∼37–30°S) includes sand dune and buried paleosol sequences that despite their potential as a proxy for past environmental change, remain mostly unstudied north of Patagonia and south of the Atacama Desert core. Here, we present results of a stratigraphic and geochronologic study using the post‐infrared infrared stimulated luminescence signal stimulated at 225 °C (pIRIR225) of potassium‐rich feldspar that show the timing of past climate variability as evidenced from sand dune/buried paleosol couplets at 32°S. Our record shows that periods of sand dune accumulation during Marine Isotope Stages MIS 6, 4, 3 and 2 occurred within ice ages and associated low sea‐level stands, probably affected by similar to, or drier than, present conditions. Intercalated wetter periods inferred from pedogenesis occurred between 53 ± 4 and 52 ± 3 ka, at some time between 52 ± 3 and 36 ± 2 ka, and at some time between 31 ± 2 and 22 ± 2 ka, and reflect times when the southern westerlies rain belt shifted north. Our data reveal that central Chile experienced multi‐millennial periodicity of westerly precipitation throughout the last glacial period. We provide evidence for a humid local Last Glacial Maximum.
Synthesis and Properties of Quaternary Ammonium Gemini Surfactants with Hydroxyethyl at Head Groups
Authors: Sun Ya , Han Fu , Zhou Yawen , Xu Baocai 
Published: March 2019

AbstractA series of cationic gemini surfactants CmH2m + 1N+(CH2CH2OH)2(CH2)sN+(CH2CH2OH)2CmH2m + 1 2Br−, referred to as m‐s‐m (OH) (m = 8,10,12, s = 3,4), were prepared by quaternization of dihydroxyethyl tertiary amines with dibromoalkane. The dihydroxyethyl tertiary amines were synthesized by nucleophilic substitution of diethanolamine with bromoalkane. The characterization of the m‐s‐m (OH) surfactants was performed using 1H NMR and MS. The surface activities and aggregation behavior in aqueous solution of the m‐s‐m (OH) surfactants were studied using surface tension measurements, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The surface tension and critical micellar concentration of these surfactants in aqueous solution decreased dramatically due to the introduction of hydroxyethyl at the head group. The micelles and/or vesicles formed in the aqueous solution of m‐s‐m (OH) surfactants were strongly dependent upon the lengths of spacer chains and carbon chains. The number of vesicles increases and that of micelles decreases when the lengths of spacer chains and carbon chains increase.
Associations Among Hair Cortisol Concentrations, Posttraumatic Stress Disorder Status, and Amygdala Reactivity to Negative Affective Stimuli in Female Police Officers
Authors: van Zuiden Mirjam , Savas Mesut , Koch Saskia B.J. , Nawijn Laura , Staufenbiel Sabine M. , Frijling Jessie L. , Veltman Dick J. , van Rossum Elisabeth F.C. , Olff Miranda 
Published: March 2019

AbstractPosttraumatic stress disorder (PTSD) is associated with altered hypothalamic‐pituitary‐adrenal (HPA) axis function. Measurement of hair cortisol concentrations (HCC) allows retrospective assessment of HPA axis regulation over prolonged periods of time. Currently, research investigating HCC in PTSD remains sparse. Previous cross‐sectional studies have included only civilian populations, although it is known that trauma type moderates associations between PTSD status and HPA axis function. We investigated differences in HCC between trauma‐exposed female police officers with current PTSD (n = 13) and without current and lifetime PTSD (n = 15). To investigate whether HCC was associated with neural correlates of PTSD, we additionally performed exploratory correlational analyses between HCC and amygdala reactivity to negative affective stimuli. We observed significantly lower HCC in participants with PTSD than in participants without PTSD, d = 0.89. Additionally, within participants with PTSD, we observed positive correlations between HCC and right amygdala reactivity to negative affective (vs. happy/neutral) faces, r = .806 (n = 11) and left amygdala reactivity to negative affective (vs. neutral) pictures, r = .663 (n = 10). Additionally, left amygdala reactivity to negative faces was positively correlated with HCC in trauma‐exposed controls, r = .582 (n = 13). This indicates that lower HCC is associated with diminished amygdala differentiation between negative affective and neutral stimuli. Thus, we observed lower HCC in trauma‐exposed noncivilian women with PTSD compared to those without PTSD, which likely reflects prolonged HPA axis dysregulation. Additionally, HCC was associated with hallmark neurobiological correlates of PTSD, providing additional insights into pathophysiological processes in PTSD.
Computational Fluid Dynamics Analysis of Surgical Approaches to Bilateral Vocal Fold Immobility
Authors: Rios Gabriel , Morrison Robert J. , Song Yi , Fernando Shanik J. , Wootten Christopher , Gelbard Alexander , Luo Haoxiang 
Published: March 2019

ObjectivesBilateral vocal fold immobility (BVFI) is a rare and life‐threatening condition in which both vocal folds are fixed, resulting in airway obstruction associated with life‐threatening respiratory compromise. Treatment of BVFI is largely surgical and remains an unsatisfactory compromise between voice, breathing, and swallowing. No comparisons between currently employed techniques currently exist. We sought to employ computational fluid dynamics (CFD) modeling to delineate the optimal surgical approach for BVFI.MethodsUtilizing clinical computed tomography of BVFI subjects, coupled with image analytics employing CFD models and subject pulmonary function data, we compared the airflow features in the baseline pathologic states and changes seen between endoscopic cordotomy, endoscopic suture lateralization, and posterior cricoid expansion.ResultsCFD modeling demonstrated that the greatest airflow velocity occurs through the posterior glottis on inspiration and anterior glottis on expiration in both the normal condition and in BVFI. Glottic airflow velocity and resistance were significantly higher in the BVFI condition compared to normal. Geometric indices (cross‐sectional area of airway) were lower in posterior cricoid expansion surgery when compared to alternate surgical approaches. CFD measures (airflow velocity and resistance) improved with all surgical approaches but were superior with posterior cricoid expansion.ConclusionCFD modeling can provide discrete, quantitative assessment of the airflow through the laryngeal inlet, and offers insights into the pathophysiology and changes that occur after surgery for BVFI.Level of EvidenceNA. Laryngoscope, 130:E57–E64, 2020
Evaluating Efficacy of Antimicrobial and Antifouling Materials for Urinary Tract Medical Devices: Challenges and Recommendations
Authors: Ramstedt Madeleine , Ribeiro Isabel A. C. , Bujdakova Helena , Mergulhão Filipe J. M. , Jordao Luisa , Thomsen Peter , Alm Martin , Burmølle Mette , Vladkova Todorka , Can Fusun , Reches Meital , Riool Martijn , Barros Alexandre , Reis Rui L. , Meaurio Emilio , Kikhney Judith , Moter Annette , Zaat Sebastian A. J. , Sjollema Jelmer 
Published: March 2019

AbstractIn Europe, the mean incidence of urinary tract infections in intensive care units is 1.1 per 1000 patient‐days. Of these cases, catheter‐associated urinary tract infections (CAUTI) account for 98%. In total, CAUTI in hospitals is estimated to give additional health‐care costs of £1–2.5 billion in the United Kingdom alone. This is in sharp contrast to the low cost of urinary catheters and emphasizes the need for innovative products that reduce the incidence rate of CAUTI. Ureteral stents and other urinary‐tract devices suffer similar problems. Antimicrobial strategies are being developed, however, the evaluation of their efficacy is very challenging. This review aims to provide considerations and recommendations covering all relevant aspects of antimicrobial material testing, including surface characterization, biocompatibility, cytotoxicity, in vitro and in vivo tests, microbial strain selection, and hydrodynamic conditions, all in the perspective of complying to the complex pathology of device‐associated urinary tract infection. The recommendations should be on the basis of standard assays to be developed which would enable comparisons of results obtained in different research labs both in industry and in academia, as well as provide industry and academia with tools to assess the antimicrobial properties for urinary tract devices in a reliable way.
Temperature‐induced self‐assembly and metal‐ion stabilization of histidine functional block copolymers
Authors: Brisson Emma R. L. , Griffith James C. , Bhaskaran Ayana , Franks George V. , Connal Luke A. 
Published: March 2019

ABSTRACTHistidine functional block copolymers are thermally self‐assembled into polymer micelles with poly‐N‐isopropylacrylamide in the core and the histidine functionality in the corona. The thermally induced self‐assemblies are reversible until treated with Cu2+ ions at 50 °C. Upon treatment with 0.5 equivalents of Cu2+ relative to the histidine moieties, metal‐ion coordination locks the self‐assemblies. The self‐assembly behavior of histidine functional block copolymers is explored at different values of pH using DLS and 1H NMR. Metal‐ion coordination locking of the histidine functional micelles is also explored at different pH values, with stable micelles forming at pH 9, observed by DLS and imaged by atomic force microscopy. The thermal self‐assembly of glycine functional block copolymers at pH 5, 7, and 9 is similar to the histidine functional materials; however, the self‐assemblies do not become stable after the addition of Cu2+, indicating that the imidazole plays a crucial role in metal‐ion coordination that locks the micelles. The reversibility of the histidine‐copper complex locking mechanism is demonstrated by the addition of acid to protonate the imidazole and destabilize the polymer self‐assemblies. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1964–1973
Recyclable helical poly(phenylacetylene)‐supported catalyst for asymmetric aldol reaction in aqueous media
Authors: Zhang Chunhong , Qiu Yuan , Bo Siyuan , Wang Fuqingyun , Wang Yudan , Liu Lijia , Zhou Yanli , Niu Haijun , Dong Hongxing , Satoh Toshifumi 
Published: March 2019

ABSTRACTA novel one‐handed helical poly(phenylacetylene) bearing L‐hydroxyproline pendants (poly(PA‐P)) was synthesized as an eco‐friendly polymer‐supported catalyst for asymmetric reactions. The helical poly(PA‐P) catalyzed the asymmetric aldol reactions of cyclohexanone with p‐nitrobenzaldehyde, and showed good recyclability and higher enantiomeric excess (ee) in aqueous medias than that in organic medias. The one‐handed helicity of poly(PA‐P) was clearly affected by the water content in the aqueous media. The helical poly(PA‐P) showed the higher enantioselectivity (ee = 99%) than its monomer PA‐P (ee = 54%) in THF/H2O (H2O vol % = 25.0 vol %). After the one‐handed helical structure of poly(PA‐P) was destroyed by grinding treatment, the ee of the reaction clearly decreased from 99 to 49%. These indicate that the one‐handed helical structure of poly(PA‐P) played an important role in the high enantioselectivity of the asymmetric aldol reactions in the aqueous media. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1024–1031