bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Serine‐Proteinase‐Catalyzed Peptide Splicing in Analogues of Sunflower Trypsin Inhibitor 1 (SFTI‐1)
Authors: Karna Natalia , Łęgowska Anna , Malicki Stanisław , Dębowski Dawid , Golik Przemysław , Gitlin Agata , Grudnik Przemysław , Wladyka Benedykt , Brzozowski Krzysztof , Dubin Grzegorz , Rolka Krzysztof
Published: July 2015

Serine‐proteinase‐catalyzed peptide splicing was demonstrated in analogues of the trypsin inhibitor SFTI‐1: both single peptides and two‐peptide chains (C‐ and N‐terminal peptide chains linked by a disulfide bridge). In the second series, peptide splicing with catalytic amount of proteinase was observed only when formation of acyl–enzyme intermediate was preceded by hydrolysis of the substrate Lys–Ser peptide bond. Here we demonstrate that with an equimolar amount of the proteinase, splicing occurs in all the two‐peptide‐chain analogues. This conclusion was supported by high resolution crystal structures of selected analogues in complex with trypsin. We showed that the process followed a direct transpeptidation mechanism. Thus, the acyl–enzyme intermediate was formed and was immediately used for a new peptide bond formation; products associated with the hydrolysis of the acyl–enzyme were not observed. The peptide splicing was sequence‐ not structure‐specific.
Droplet‐Shooting and Size‐Filtration (DSSF) Method for Synthesis of Cell‐Sized Liposomes with Controlled Lipid Compositions
Authors: Morita Masamune , Onoe Hiroaki , Yanagisawa Miho , Ito Hiroaki , Ichikawa Masatoshi , Fujiwara Kei , Saito Hirohide , Takinoue Masahiro
Published: July 2015

We report a centrifugal microfluidic method, droplet‐shooting and size‐filtration (DSSF), for the production of cell‐sized liposomes with controlled lipid compositions. This involves the generation of large and small droplets from the tip of a glass capillary and the selective transfer of small droplets through an oil‐water interface, thus resulting in the generation of cell‐sized liposomes. We demonstrate control of the microdomain formation as well as the formation of asymmetric lipid bilayer liposomes of uniform size by the control of lipid composition. The DSSF method involves simple microfluidics and is easy to use. In addition, only a small volume (0.5–2 μL) of sample solution is required for the formation of hundreds of cell‐sized liposomes. We believe that this method can be applied to generate cell‐sized liposomes for a wide variety of uses, such as the construction of artificial cell‐like systems.
Temporary tattoos: A viable treatment strategy for nonsuicidal self‐injury?
Authors: Masters Kim J.
Published: July 2015

Nonsuicidal self‐injury (NSSI) has a typical onset between ages 12 and 14 with a community prevalence of 13% to 28% among adolescents and 40% to 80% in psychiatric patients. Girls usually deliberately hurt themselves with cuts to their arms, legs, and abdomen; abrade their skin with erasers; or burn themselves with cigarettes. Boys use self‐harm less often and usually hit themselves, sometimes resulting in intentional fractures.
Juvenile justice facilities are changing with the times
Authors: Fritz Gregory K.
Published: July 2015

In case you hadn't noticed it, there is a quiet revolution going on in the world of juvenile justice and detention. Slowly but inexorably, state by state, the rules for the detention of delinquent minors are changing. The changes reflect a growing recognition that children and adolescents are still developing in important neurobiologic, cognitive, and socioemotional domains — and thus can't simply be treated as small adults.
Kids in the Summer: A Guide for Parents
Authors: Knopf Alison
Published: July 2015

To succeed in school and life, children and young adults need ongoing opportunities to learn and practice essential skills. This is especially true during the summer months. Many Americans have a wonderful image of summer as a carefree, happy time when kids can be kids, and take for granted the prospect of enriching experiences such as summer camps, time with family, and trips to museums, parks, and libraries. Unfortunately, some youth face anything but idyllic summer months. When the school doors close, many children struggle to access educational opportunities, as well as basic needs such as healthy meals and adequate adult supervision. Parents consistently cite summer as the most difficult time to ensure that their children have productive things to do. This handout provides some suggestions and resources for keeping kids, adolescents, and teens engaged and active during the summer months.
Electron‐Transfer Kinetics in Polymetallic Carbon‐Rich Ruthenium(II) Bis(σ‐arylacetylides) Wires Connected to Gold
Authors: Mulas Andrea , Hervault Yves‐Marie , Norel Lucie , Rigaut Stéphane , Lagrost Corinne
Published: July 2015

Molecular wires consisting of RuII bis(σ‐arylacetylide) organometallics functionalized with different anchoring groups (thiol, isocyanide) connected with different bridges [Ø, −CH2−, −O−(CH2)6−] were self‐assembled onto gold surfaces. The materials were characterized through wettability, ellipsometric, infrared absorption reflection, and electrochemical measurements. The dynamics of the electron transfers within the monolayers were examined with high‐speed voltammetry. Similar fast electron‐transfer dynamics (104 s−1) associated with discrete oxidation events (up to four distinct oxidation states) at remarkably low potentials (≤0.7 V vs. SCE) were observed for all complexes. Neither the extension of the molecular wires, nor the variation in the anchoring/bridging units, led to the decrease in electron‐transfer kinetics. These results highlight the potential of RuII bis(σ‐arylacetylide) complexes as a charge‐storage medium for processing information in multibit devices with low power consumption.
Cyclotrimerization‐Induced Chiral Supramolecular Structures of 4‐Ethynyltriphenylamine on Au(111) Surface
Authors: Xiang Feifei , Lu Yan , Li Chao , Song Xin , Liu Xiaoqing , Wang Zhongping , Liu Juan , Dong Mingdong , Wang Li
Published: July 2015

Cyclotrimerization‐induced chiral supramolecular structures of 4‐ethynyltriphenylamine (ETPA) have been synthesized on the Au(111) surface through alkyne‐based reactions. Whereas the ETPA molecules adsorbed on the Au(111) surface remain inert and form a close‐packed self‐assembled structure at room temperature, the combination of scanning tunneling microscopy observations and theoretical calculations unambiguously reveal that the ETPA molecules cyclotrimerize to form new trimer‐like species—1,3,5‐tris[4‐(diphenylamino)phenyl]benzene (TPAPB)—after annealing at 323 K. Further annealing drives these cyclotrimerized TPAPB molecules to form chiral hexagonal supramolecular structures with an extraordinary self‐healing ability.
Two Symmetrically Bis‐substituted Pyrene Derivatives: Synthesis, Photoluminescence, and Electroluminescence
Authors: Gong Xiaojie , Xie Xiang , Chen Naiwu , Zheng Chaoyue , Zhu Jie , Chen Runfeng , Huang Wei , Gao Deqing
Published: July 2015

Two kinds of cyanophenyl terminated pyrene derivatives for organic light‐emitting diodes were synthesized and characterized by UV/Vis, fluorescence (FL), 1H NMR, MALDI‐TOF, CV and TGA. Both compounds exhibited blue photoluminescence and high fluorescent quantum yield of 85% and 75% in solutions. Due to the presence of acetylene spacer, the compound distinguishes itself by high coplanarity, high thermal stability, little Stokes' shift and clear excimer formation in the solid state from the acetylene‐free compound. In order to suppress the molecular aggregation, the electroluminescent properties were studied by doing the materials in PVK. The result proved that energy transfer happened from the host PVK to the materials.
An imputation based empirical likelihood approach to pretest–posttest studies
Authors: Chen Min , Wu Changbao , Thompson Mary E.
Published: July 2015

Pretest–posttest studies are an important and popular method for assessing treatment effects or the effectiveness of an intervention in many areas of scientific research. There are two distinct features for this type of study: availability of baseline information for all subjects in the study and missingness by design of measures of the responses. Important recent research advances on this topic include Leon et al. (2003) on efficient estimation of the treatment effect, and Huang et al. (2008) on a semi‐parametric estimation procedure based on empirical likelihood (EL) where the mean responses for the treatment group and the control group are handled separately. EL ratio confidence intervals or tests for the treatment effect, however, cannot be constructed under the approach used by Huang et al. (2008). In this paper, we use an alternative EL formulation, which directly involves the parameter of interest, i.e., the treatment effect, and incorporates baseline information through an imputation approach. Our focus is to derive the EL ratio confidence intervals and tests for the treatment effect under the proposed imputation‐based framework. Theoretical results are developed, and finite sample performances of the proposed methods with comparison to existing approaches are investigated through simulation studies. An application to a real data set is also presented. The Canadian Journal of Statistics 43: 378–402; 2015 © 2015 Statistical Society of Canada
Gas‐Induced Reversible Dispersion/Aggregation of Graphene
Authors: He Shuai , Qu Meizhen , Feng Yujun
Published: July 2015

The low dispersibility of graphene in water, given its hydrophobic nature, is considered a serious problem that limits its use. Here, we describe a method to stably disperse graphene using a dispersant containing a tertiary amine and a pyrene group. The dispersant modifies the graphene surface via π–π stacking, allowing it to be dispersed in water. The dispersant undergoes a hydrophobic–hydrophilic transition upon being stimulated by CO2 and N2, exhibiting a faster response (reaction time of 1.5 min) and lower recovery temperature (40 °C) than those of compounds with amidine‐like structures. We found that the graphene modified by this gas‐sensitive dispersant exhibited reversible dispersion/aggregation behavior upon the bubbling/removal of CO2. The proposed method is a simple one for the reversible dispersion/aggregation of graphene by stimulating it with a gas and should be suitable for fabricating sensors, drug‐delivery systems, “smart” surfaces, and switching devices.
Synthesis and Solid‐State NMR Studies of Proton‐Conducting Mesoporous Niobium Oxide Polymer Composites with Nafion‐Like Thermal Durability
Authors: Turley Jonathan P. , Romer Frederik , Trudeau Michel L. , Smith Mark E. , Hanna John V. , Antonelli David M.
Published: July 2015

Proton conductivity and thermal durability studies were performed on a series of mesoporous Nb2O5 composites with naphthalene sulfonate formaldehyde resin polymerized within the pores. The proximity of the sulfonate groups of the polymer to the walls of the oxide mesostructure was deliberately tailored to ensure superior dehydration resistance crucial to proton conductivity. Initially characterized by nitrogen adsorption, XRD, TGA and STEM, subsequent study using impedance spectroscopy over a temperature range of 20–150 °C established their proton conductivity performance. The most promising sample displayed a conductivity of 21.77 mS cm−1 at 80 °C surpassing the literature value for Nafion 117 (8 mS cm−1) as measured in our labs using the same setup. Subsequent thermal durability tests demonstrated that this composite maintains superior conductivity to Nafion 117 at 80 °C for the length of the study (24 h). These observations were rationalized by in depth solid‐state NMR studies.
Local‐in‐Time Existence and Uniqueness of Solutions to the Prandtl Equations by Energy Methods
Authors: Masmoudi Nader , Wong Tak Kwong
Published: July 2015

We prove local existence and uniqueness for the two‐dimensional Prandtl system in weighted Sobolev spaces under Oleinik's monotonicity assumption. In particular we do not use the Crocco transform or any change of variables. Our proof is based on a new nonlinear energy estimate for the Prandtl system. This new energy estimate is based on a cancellation property that is valid under the monotonicity assumption. To construct the solution, we use a regularization of the system that preserves this nonlinear structure. This new nonlinear structure may give some insight into the convergence properties from the Navier‐Stokes system to the Euler system when the viscosity goes to 0. © 2015 Wiley Periodicals, Inc.
Dynamical behavior of a generalized Lorenz system model and its simulation
Authors: Zhang Fuchen , Liao Xiaofeng , Zhang Guangyun
Published: July 2015

In this article, the dynamical behavior of a generalized Lorenz system is derived based on stability theory of dynamical systems. The meaningful contribution of this article is that the domain of attraction of the new chaotic system is studied in detailed. Finally, numerical simulations are given to verify the effectiveness and correctness of the obtained results. © 2015 Wiley Periodicals, Inc. Complexity 21: 99–105, 2016
Use this toolkit to comply with state authorization rules
Authors: O'Sullivan Gerard P.
Published: July 2015

Under 34 CFR 600.9, all institutions of higher education that seek to recruit and enroll students in states other than those where they are chartered and licensed (their “home states”) must apply — and sometimes annually — for authorization to up to 77 agencies, a number that includes 50 states, nine territories, and the District of Columbia. Sixteen of these states require out‐of‐state IHEs to register with other offices, like commerce or state departments, and to function as registered foreign agents.
Avoid defamation claims when telling institution's story during a crisis
Authors: Prywes Daniel I. , Sobel Scott
Published: July 2015

If officials at colleges and universities draw conclusions quickly during a crisis, and announce them publicly, they risk facing defamation claims by affected individuals if the statements later prove to be incorrect. But if officials wait too long to acknowledge or condemn misconduct, the institution may immediately lose far more in the court of public opinion than the expense of a defamation suit. In some cases, reputational interests may need to take precedence.
Take 3 steps to create a fair process to investigate sexual assault
Authors: Becnel Philip
Published: July 2015

In the debate about the prevalence of sexual assaults on college campuses, false accusations are almost invariably dismissed as being so uncommon as to be insignificant. My basis of belief concerning the underestimation of false accusations is admittedly anecdotal, but it is based upon 15 years of investigating sexual assaults (among other things) and encountering firsthand cases in which alleged victims have either recanted or where there was very clear evidence that the accusation was fabricated. It is true that these cases are rare, but they do happen and are devastating to the accused. Therefore, the possibility of false accusations should be explicitly acknowledged when colleges are figuring out ways to address sexual assaults and other sexual misconduct on campuses.
Define where you want to go to build a roadmap to excellence
Authors: Sutton Halley
Published: July 2015

SAN ANTONIO, TEXAS — Looking to improve your office and workplace performance and efficiency? Do you struggle with feeling like you don't know how to make your office truly “great”?
Indirect effects of habitat disturbance on invasion: nutritious litter from a grazing resistant plant favors alien over native Collembola
Authors: Leinaas Hans Petter , Bengtsson Jan , Janion‐Scheepers Charlene , Chown Steven L.
Published: July 2015

Biological invasions are major threats to biodiversity, with impacts that may be compounded by other forms of environmental change. Observations of high density of the invasive springtail (Collembola),Hypogastrura manubrialisin heavily grazed renosterveld vegetation in the Western Cape, South Africa, raised the question of whether the invasion was favored by changes in plant litter quality associated with habitat disturbance in this vegetation type. To examine the likely mechanisms underlying the high abundance ofH. manubrialis, cages with three types of naturally occurring litter with different nutrient content were placed out in the area and collected after different periods of time.Hypogastrura manubrialiswas mainly found in the nutrient‐rich litter of the yellowbush (Galenia africana), which responds positively to disturbance in the form of overgrazing. This suggests that invasion may have been facilitated by a positive interaction with this grazing resistant plant. By contrast, indigenous Collembola were least abundant in yellowbush litter. Negative correlations between high abundance ofH. manubrialisand the abundance and diversity of other species suggest that competitive interactions might underlie low abundance of these other species at the patch level. Group behavior enablesH. manubrialisto utilize efficiently this ephemeral, high quality resource, and might improve its competitive ability. The results suggest that interactions among environmental change drivers may lead to unforeseen invasion effects.H. manubrialisis not likely to be very successful in un‐grazed renosterveld, but in combination with grazing, favoring the nutrient‐rich yellowbush, it may become highly invasive. Field manipulations are required to fully verify these conclusions.
Experimental and Theoretical Investigations of CO2 Sorption by a 3D In‐MOF with Multiple 1D Channels
Authors: Gu Ja‐Min , Hong Jin‐Yeon , Won Yong Sun , Park Sung Soo , Huh Seong
Published: July 2015

The CO2 sorption capacity of the 3D In‐MOF (Et2NH2)[In(2,6‐NDC)2]·2H2O·DEF (I) (where 2,6‐NDC is 2,6‐naphthalenedicarboxylate and DEF is N,N‐diethylformamide) was investigated. The solvent‐free I contains three distinct types of 1D micropores with different shapes and pore dimensions. The evacuated I sorbed 297.2 cm3 g–1 (13.3 mmol g–1) of CO2 at 196 K, 72.2 cm3 g–1 (3.22 mmol g–1) at 273 K, and 39.8 cm3 g–1 (1.78 mmol g–1) at 298 K. The difference between the uptake at 196 K and those at 273 and 298 K is relatively large. The shapes of the sorption isotherms are also dramatically different. At 196 K, the adsorption–desorption isotherms are S‐shaped without significant hysteretic behavior between the adsorption and desorption branches. On the contrary, the adsorption isotherms measured at 273 and 298 K fit well with the Langmuir–Freundlich equation. The low‐surface‐coverage isosteric heat (Qst) of CO2 adsorption by I is 19.6 kJ mol–1. Detailed estimations of the adsorption sites for CO2 were then performed by DFT calculations. The calculated binding energies were typically dependent on the dimension of the micropores when nonbonding (van der Waals) interactions were considered; the larger the micropore dimensions, the smaller the calculated binding energy. In addition, not only the framework CH···OCO contacts for Ch3 but also the counter‐cation CH···OCO contacts for Ch1 and Ch2 were found to be important.
Mechanisms of Oxygen Atom Transfer between Main‐Group Elements
Authors: Conradie Jeanet , Berg Steffen , Ghosh Abhik
Published: July 2015

Oxygen atom transfer (OAT) between main‐group elements is pivotal to a number of industrial processes such as the synthesis of thionyl chloride (SO3 + SCl2 → SO2 + SOCl2) and sodium chlorate (3 NaOCl → NaClO3 + 2 NaCl), as well as the historic method of CO detection in mines via its reaction with I2O5 (I2O5 + 5 CO → I2 + 5 CO2). Surprisingly, little is known about the mechanisms of these and other OAT reactions involving main‐group elements. Even the basic question as to whether such reactions are one‐step, SN2‐like displacements or multistep, involving oxo‐bridged intermediates, remains largely unanswered. Extensive density functional theory calculations reported herein indicate a direct, SN2‐like pathway as the norm for such processes.
Derivation of water quality standards for carbamazepine, metoprolol, and metformin and comparison with monitoring data
Authors: Moermond Caroline T.A. , Smit C. Els
Published: July 2015

Environmental quality standards (EQSs) for 3 pharmaceuticals in surface water were derived: carbamazepine (epilepsy), metoprolol (heart failure), and metformin (diabetes). In recent years, these pharmaceuticals have been detected frequently in Dutch surface waters. The proposed standards are based on ecotoxicity data from national and European authorization dossiers and additional information obtained from open literature. The methods used are in accordance with the methodology of the Water Framework Directive and national frameworks for risk limit derivation. Only the exposure route regarding direct ecotoxic effects on ecosystems could be taken into account for deriving EQSs. The exposure route of secondary poisoning of fish-eating animals was not triggered, and not enough data were available or accessible to derive an EQS for the exposure of humans due to consumption of fish. Monitoring data for surface waters worldwide show that the proposed quality standards for carbamazepine may be exceeded. It could be expected that when carbamazepine use increases or effluents are diluted less during dry seasons, standards will be exceeded more often. Environ Toxicol Chem 2016;35:882–888. © 2015 SETAC
Contrasting PCB bioaccumulation patterns among Lake Huron lake trout reflect basin-specific ecology
Authors: Paterson Gordon , Ryder Mark , Drouillard Ken G. , Haffner G. Douglas
Published: July 2015

This study collected multiple age classes of lake trout from Lake Huron's Main Basin, Georgian Bay, and North Channel regions to compare and contrast top predator polychlorinated biphenyl (PCB) bioaccumulation patterns in separate compartments of the same ecosystem. Sum PCB concentrations were highest for Main Basin (260 ± 24.9 ng g−1 wet wt) fish, followed by Georgian Bay (74.6 ± 16.2 ng g−1) and North Channel (42.0 ± 3.3 ng g−1) fish. Discriminant functions analysis of lake trout PCB profiles and stable carbon (δ13C) and nitrogen (δ15N) isotope values clearly distinguished fish by location, indicating high degrees of basin fidelity throughout their lifetimes in addition to highly contrasting PCB bioaccumulation profiles. These unique profiles were not attributable to significant differences in lake trout lipid contents (p = 0.856) or trophic position (δ15N; p = 0.334), with rainbow smelt representing the primary prey across the basins. Furthermore, significant differences were observed among the basins for the relationships between PCB biomagnification factors and hydrophobicity. An empirical model for predicting PCB biomagnification in Lake Huron lake trout indicated that basin-specific population growth rates and prey abundances were significant for explaining these contrasting patterns of PCB bioaccumulation. The results of the present study are fundamental for understanding the role of ecology in legacy persistent organic pollutant (POP) bioaccumulation. Specifically, ecosystem characteristics such as prey abundances, foraging ecology, and ultimately consumer growth can regulate the variability of legacy POP bioaccumulation as observed within and among a wide range of freshwater ecosystems. Environ Toxicol Chem 2016;35:65–73. © 2015 SETAC
Effect of test concentration in the ready biodegradability test for chemical substances: Improvement of OECD test guideline 301C
Authors: Nabeoka Ryosuke , Taruki Masanori , Kayashima Takakazu , Yoshida Tomohiko , Kameya Takashi
Published: July 2015

In Japan, understanding the environmental persistence of chemicals is very important for risk assessment, and ready biodegradability tests are mainly conducted according to the Organisation for Economic Co-operation and Development test guideline 301C. However, the highest test concentration specified in test guideline 301C, 100 mg/L, may cause microbial toxicity and incomplete biodegradation. The authors performed test guideline 301C tests at test concentrations of 30 mg/L for 13 substances that were readily biodegradable in ready biodegradability tests but not in test guideline 301C tests. Of the 5 substances with potential to cause microbial toxicity at 100 mg/L, the percentage of biodegradation of sodium dimethyldithiocarbamate, 4-chloro-3-cresol (CC), thymol (THY), and p-tert-butyl-α-methylbenzenepropionaldehyde measured by biochemical oxygen demand (BOD) increased in the test guideline 301C test at 30 mg/L, suggesting a reduction in toxicity effects. Furthermore, CC and THY met the criteria for ready biodegradability, which are more than 60% of biodegradation by BOD and a 10-d window. Of the 8 substances with a low potential for causing microbial toxicity at 100 mg/L, the percentage of biodegradation of only 2-(diethylamino)ethanol increased in the test guideline 301C test at 30 mg/L. Employing a lower test concentration in the standard test guideline 301C test will contribute to improvement of consistency between results of a test guideline 301C test and other ready biodegradability tests. Environ Toxicol Chem 2016;35:84–90. © 2015 SETAC
The impacts of organic matter on the distribution and methylation of mercury in a hydroelectric reservoir in Wujiang River, Southwest China
Authors: Meng Bo , Feng Xinbin , Qiu Guangle , Li Zhonggen , Yao Heng , Shang Lihai , Yan Haiyu
Published: July 2015

To understand the impacts of organic matter on the geochemical processing of Hg in a hydroelectric reservoir, spatial and seasonal distributions of total mercury (THg) and methylmercury (MeHg) in both solid and liquid phases of sediment cores were investigated in the Wujiangdu Reservoir in Guizhou Province, China. Four sampling sites with different intensities of cage aquaculture activities were chosen and were evenly distributed from upstream to downstream of the Wujiangdu Reservoir. Elevated MeHg concentrations and the high percentage of MeHg in solid and liquid phases of the surface sediment demonstrated that the active Hg methylation process occurred downstream of the Wujiangdu Reservoir. In contrast, the absence of obvious peaks for MeHg in sediment from the upper reaches of the Wujiangdu Reservoir, consistent with low levels of organic matter, suggested that production of MeHg was limited. In sediment with high organic matter content, reduction occurred closer to the sediment surface, resulting in maximum MeHg concentration in these layers. The correlation between MeHg and organic carbon implied that organic matter content in the sediment originating from cage aquaculture activities can help to predict MeHg production rates in reservoirs, which could be used to assess possible MeHg contamination in a reservoir ecosystem. Environ Toxicol Chem 2016;35:191–199. © 2015 SETAC
Surface ocean CO2 in 1990–2011 modelled using a feed‐forward neural network
Authors: Zeng Jiye , Nojiri Yukihiro , Nakaoka Shin‐ichiro , Nakajima Hideaki , Shirai Tomoko
Published: July 2015

This dataset includes the monthly distributions of CO2 fugacity in the world surface oceans reconstructed using a feed‐forward neural network model and the CO2 measurements of the Surface Ocean CO2 Atlas version 2.0. It has a spatial resolution of 1 × 1° and spans a period of 22 years, from January 1990 to December 2011. The dataset also includes necessary parameters for the reconstruction and an estimate of the CO2 fluxes between the ocean and the atmosphere. The aim of this work is to provide a dataset for estimating the oceans' contribution to the global carbon budget.
May the surface roughness of the retrieved femoral head influence the wear behavior of the polyethylene liner?
Authors: Taddei Paola , Tozzi Silvia , Carmignato Simone , Affatato Saverio
Published: July 2015

This study was aimed at determining the surface degradation occurred on retrieved ceramic and metallic heads, as well as the influence of the head surface quality on the wear of the polyethylene counterface. To this purpose, 14 ceramic and 14 metallic femoral heads retrieved at revision surgery were examined. Scanning electron microscopic analysis provided visual evidence that some metallic heads presented crescent wear more often than the ceramic ones; the former showed a higher volumetric loss (as determined by Coordinate Measuring Machine) than the latter, but less negative Rsk values. This apparent lack of correlation between volumetric loss (i.e., wear factor) and roughness data may be explained by considering that they are two temporally variant parameters. No significant differences were observed between the Ra values of the two sets of femoral heads. The cups articulating against metal heads were characterized by higher mean wear volumes than those articulating against alumina although this difference was not statistically significant; metal heads displayed significantly higher mean wear volumes than alumina heads. The micro‐Raman analysis of the cup articulated against the most worn alumina femoral head showed an orthorhombic into monoclinic phase transformation that was not observed in the cups coupled to metal heads. The obtained results showed that the surface finishing of the femoral head (in terms of Rsk values) determined the morphological changes experienced by the ultra‐high‐molecular‐weight polyethylene crystalline phase at the molecular level. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1374–1385, 2016.
Compensatory Changes in Calcium Metabolism Accompany the Loss of Vitamin D Receptor (VDR) From the Distal Intestine and Kidney of Mice
Authors: Reyes-Fernandez Perla C , Fleet James C
Published: July 2015

1,25 Dihydroxyvitamin D3 (1,25(OH)2D) increases intestinal Ca absorption when dietary Ca intake is low by inducing gene expression through the vitamin D receptor (VDR). 1,25(OH)2D-regulated Ca absorption has been studied extensively in the small intestine, but VDR is also present in the large intestine. Our goal was to determine the impact of large intestinal VDR deletion on Ca and bone metabolism. We used transgenic mice expressing Cre-recombinase driven by the 9.5-kb human caudal type homeobox 2 (CDX2) promoter to delete floxed VDR alleles from the caudal region of the mouse (CDX2-KO). Weanling CDX2-KO mice and control littermates were fed low (0.25%) or normal (0.5%) Ca diets for 7 weeks. Serum and urinary Ca, vitamin D metabolites, bone parameters, and gene expression were analyzed. Loss of the VDR in CDX2-KO was confirmed in colon and kidney. Unexpectedly, CDX2-KO had lower serum PTH (–65% of controls, p < 0.001) but normal serum 1,25(OH)2D and Ca levels. Despite elevated urinary Ca loss (eightfold higher in CDX2-KO) and reduced colonic target genes TRPV6 (–90%) and CaBPD9k (–80%) mRNA levels, CDX2-KO mice had only modestly lower femoral bone density. Interestingly, duodenal TRPV6 and CaBPD9k mRNA expression was fourfold and threefold higher, respectively, and there was a trend toward increased duodenal Ca absorption (+19%, p = 0.076) in the CDX2-KO mice. The major finding of this study is that large intestine VDR significantly contributes to whole-body Ca metabolism but that duodenal compensation may prevent the consequences of VDR deletion from large intestine and kidney in growing mice. © 2015 American Society for Bone and Mineral Research.
Hdac3 Deficiency Increases Marrow Adiposity and Induces Lipid Storage and Glucocorticoid Metabolism in Osteochondroprogenitor Cells
Authors: McGee-Lawrence Meghan E , Carpio Lomeli R , Schulze Ryan J , Pierce Jessica L , McNiven Mark A , Farr Joshua N , Khosla Sundeep , Oursler Merry Jo , Westendorf Jennifer J
Published: July 2015

Bone loss and increased marrow adiposity are hallmarks of aging skeletons. Conditional deletion of histone deacetylase 3 (Hdac3) in murine osteochondroprogenitor cells causes osteopenia and increases marrow adiposity, even in young animals, but the origins of the increased adiposity are unclear. To explore this, bone marrow stromal cells (BMSCs) from Hdac3-depleted and control mice were cultured in osteogenic medium. Hdac3-deficient cultures accumulated lipid droplets in greater abundance than control cultures and expressed high levels of genes related to lipid storage (Fsp27/Cidec, Plin1) and glucocorticoid metabolism (Hsd11b1) despite normal levels of Pparγ2. Approximately 5% of the lipid containing cells in the wild-type cultures expressed the master osteoblast transcription factor Runx2, but this population was threefold greater in the Hdac3-depleted cultures. Adenoviral expression of Hdac3 restored normal gene expression, indicating that Hdac3 controls glucocorticoid activation and lipid storage within osteoblast lineage cells. HDAC3 expression was reduced in bone cells from postmenopausal as compared to young women, and in osteoblasts from aged as compared to younger mice. Moreover, phosphorylation of S424 in Hdac3, a posttranslational mark necessary for deacetylase activity, was suppressed in osseous cells from old mice. Thus, concurrent declines in transcription and phosphorylation combine to suppress Hdac3 activity in aging bone, and reduced Hdac3 activity in osteochondroprogenitor cells contributes to increased marrow adiposity associated with aging. © 2015 American Society for Bone and Mineral Research.
Efficacy and safety of therapeutic plasma exchange by using apheresis devices in pediatric atypical hemolytic uremic syndrome patients
Authors: Hans Rekha , Sharma Ratti Ram , Marwaha Neelam , Suri Deepti , Kumar Rakesh , Gupta Anju , Singh Surjit
Published: July 2015

Background:

Therapeutic plasma exchange (TPE) in atypical hemolytic uremic syndrome (aHUS) is considered as first line treatment as per current American Society for Apheresis (ASFA) guidelines. But there is very limited data available in the literature regarding efficacy and safety of TPE procedures in pediatric aHUS patients.

Aim:

To assess the safety and efficacy of TPE by using apheresis devices in pediatric aHUS patients.

Materials and Methods:

We did a retrospective analysis of all TPE procedures performed in aHUS pediatric patients over a period of 13 years (2001–2013). TPE procedures were done on two different devices daily or on alternate days depending on clinical condition of the patient. Adverse events if any were noted and analyzed. Pre and post procedural laboratory profiles were analyzed to assess the response to TPE therapy and patients were categorized accordingly.

Results:

A total of 169 TPE procedures (range of 1–22/patient with an average of 7.6 procedures/patient) were performed on 30 pediatric patients. Twenty four patients had more than 3 TPE procedures. Sixteen patients were complete responders, 5 were partial responders and 3 were non responders. The time between onset of illness and start of TPE therapy was 1–4 days in complete responders, 5–7 days in partial responders and 8–9 days in non‐ responders. Adverse events were observed in 13 (7.7%) procedures.

Conclusion:

TPE is a safe and effective therapeutic modality in pediatric aHUS if instituted early in the course of disease with a minimum of four to five procedures. J. Clin. Apheresis 31:381–387, 2016. © 2015 Wiley Periodicals, Inc.
The influence of MicroRNA‐150 in Osteoblast Matrix Mineralization
Authors: Dong Chun‐Ling , Liu Hao‐Zhi , Zhang Zhen‐Chun , Zhao Huan‐Li , Zhao Hui , Huang Yan , Yao Jian‐Hua , Sun Tian‐Sheng
Published: July 2015

This study investigated the influence of miR‐150 expression on osteoblast matrix mineralization and its mechanisms. The mouse osteoblast cell line MC3T3‐E1 was used as an in vitro model of bone formation. On the fifth day of mineralization, transfection experiments using agomiR‐150, agomiR‐NC, antagomiR‐150 antagomiR‐NC, and mock groups were set up to test the effects of miR‐150 in MC3T3‐E1 model. The mRNA and protein levels of OC, ALP, type I collagen, and OPN were measured by qRT‐PCR and ELISA. Matrix mineralization was detected by alizarin red S (ARS) staining and flow cytometry was employed to quantify apoptosis in each group. RT‐PCR and Western blot were applied to detect the expression of target gene MMP14. Our results demonstrated that the endogenous expression levels of miR‐150, OC, ALP, type I collagen, and OPN in MC3T3‐E1 cells increased steadily. Exogenous expressions of agomiR‐150 and antagomiR‐150 can significantly up‐/down‐regulate, respectively, the expression level of miR‐150 in MC3T3‐E1 cells. Compared with the mock group, higher expression levels of OC, ALP, type I collagen, and OPN mRNA were observed in the agomiR‐150 group, while lower mRNA expression levels of OC, ALP, type I collagen, and OPN were found in the antagomiR‐150 group. Based on these results, potential miR‐150 targeted genes are discussed. Our results showed that miR‐150 supports the osteoblastic phenotype related to osteoblast function and bone mineralization. Thus, miR‐150 may have potential therapeutic applications in promoting bone formation in certain disease settings, such as in osteoporosis and in elderly patients. J. Cell. Biochem. 116: 2970–2979, 2015. © 2015 Wiley Periodicals, Inc.
TRAIL‐Induced Caspase Activation Is a Prerequisite for Activation of the Endoplasmic Reticulum Stress‐Induced Signal Transduction Pathways
Authors: Lee Dae‐Hee , Sung Ki Sa , Guo Zong Sheng , Kwon William Taehyung , Bartlett David L. , Oh Sang Cheul , Kwon Yong Tae , Lee Yong J.
Published: July 2015

It is well known that tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL)‐induced apoptosis can be initially triggered by surface death receptors (the extrinsic pathway) and subsequently amplified through mitochondrial dysfunction (the intrinsic pathway). However, little is known about signaling pathways activated by the TRAIL‐induced endoplasmic reticulum (ER) stress response. In this study, we report that TRAIL‐induced apoptosis is associated with the endoplasmic reticulum (ER) stress response. Human colorectal carcinoma HCT116 cells were treated with TRAIL and the ER stress‐induced signal transduction pathway was investigated. During TRAIL treatment, expression of ER stress marker genes, in particular the BiP (binding immunoglobulin protein) gene, was increased and activation of the PERK (PKR‐like ER kinase)‐eIF2α (eukaryotic initiation factor 2α)‐ATF4 (activating transcription factor 4)‐CHOP (CCAAT‐enhancer‐binding protein homologous protein) apoptotic signal transduction pathway occurred. Experimental data from use of a siRNA (small interfering RNA) technique, caspase inhibitor, and caspase‐3‐deficient cell line revealed that TRAIL‐induced caspase activation is a prerequisite for the TRAIL‐induced ER stress response. TRAIL‐induced ER stress was triggered by caspase‐8‐mediated cleavage of BAP31 (B cell receptor‐associated protein 31). The involvement of the proapoptotic PERK‐CHOP pathway in TRAIL‐induced apoptosis was verified by using a PERK knockout (PERK−/−) mouse embryo fibroblast (MEF) cell line and a CHOP−/− MEF cell line. These results suggest that TRAIL‐induced the activation of ER stress response plays a role in TRAIL‐induced apoptotic death. J. Cell. Biochem. 117: 1078–1091, 2016. © 2015 Wiley Periodicals, Inc.
Magnetic mesoporous enzyme–silica composites with high activity and enhanced stability
Authors: Cui Jiandong , Feng Yuxiao , Yue Shu , Zhao Yamin , Li Linbo , Liu Ronglin , Lin Tao
Published: July 2015

BACKGROUND

Encapsulation of enzymes in biomimetic silica seems to be a promising immobilization method due to mild processing conditions and short preparation time. However, biomimetic silica particles may be considered too small for industrial applications because they result in difficult recovery. Furthermore, the use of R5 peptide or polymers as catalyst usually causes protein denaturation. To overcome these drawbacks, a new stable and recyclable biocatalyst based on co‐encapsulation of magnetic nanoparticles and phenylalanine ammonia lyase (PAL) in biomimetic silica has been prepared using enzyme‐assisted direct condensation reactions of silicon oxide with tetramethoxysilane (TMOS).

RESULTS

Under optimal conditions (10 mg mL−1 nanoparticles, 4.5 U mL−1 PAL, 0.8 mol L−1 TMOS), the highest activity recovery (52%) of encapsulated PAL was obtained. Compared with conventional PAL encapsulated in biomimetic silica (28%), the activity recovery was increased 1.86‐fold. TEM, CLSM, magnetisation measurements, and FTIR confirmed that the magnetic nanopaticles and PAL had been co‐encapsulated into the biomimetic silica. The resulting immobilized PAL exhibited higher activity and stability than native PAL, and the immobilized PAL can be easily separated by applying a magnetic field.

CONCLUSIONS

This work provides a convenient strategy to prepare stable and easy recycled biocatalyst with excellent catalytic performance. © 2015 Society of Chemical Industry
Static and dynamic headspace analysis of instant coffee blends by proton‐transfer‐reaction mass spectrometry
Authors: Romano Andrea , Gaysinsky Sylvia , Czepa Andreas , del Pulgar José Sanchez , Cappellin Luca , Biasioli Franco
Published: July 2015

Instant coffee is a widespread product, generally related to a high consumer acceptability, also because of its ease of preparation. The present work addresses the characterization of the headspace of freshly brewed instant coffees resulting from different blends, during and immediately after preparation. The sample set consisted of 10 coffees, obtained by mixing three different blends in different proportions. The employment of Proton Transfer Reaction‐Mass Spectrometry (PTR‐MS) allowed for direct and real‐time sampling from the headspace, under conditions that mimic those that are encountered above the cup during and right after brewing. Different coffee brews were separated on the basis of the respective volatile profiles, and data showed good consistency with the respective blend compositions. When the headspace evolution was monitored during preparation, similar results were obtained in terms of blend separation; moreover, different blends displayed different and reproducible ‘signatures’ in terms of time evolution. A straightforward method for the prediction of headspace composition is proposed, allowing to predict the volatile profiles of two‐component and three‐component blends on the basis of the respective parent components. Overall, the results constitute a successful example of the applicability of PTR‐MS as a tool for product development in food science. Copyright © 2015 John Wiley & Sons, Ltd.
Direct analysis in real time mass spectrometry (DART‐MS) of highly non‐polar low molecular weight polyisobutylenes
Authors: Nagy Lajos , Nagy Tibor , Deák György , Kuki Ákos , Antal Borbála , Zsuga Miklós , Kéki Sándor
Published: July 2015

Low molecular weight polyisobutylenes (PIB) with chlorine, olefin and succinic acid end‐groups were studied using direct analysis in real time mass spectrometry (DART‐MS). To facilitate the adduct ion formation under DART conditions, NH4Cl as an auxiliary reagent was deposited onto the PIB surface. It was found that chlorinated adduct ions of olefin and chlorine telechelic PIBs, i.e. [M + Cl]− up to m/z 1100, and the deprotonated polyisobutylene succinic acid [MH]− were formed as observed in the negative ion mode. In the positive ion mode formation of [M + NH4]+, adduct ions were detected. In the tandem mass (MS/MS) spectra of [M + Cl]−, product ions were absent, suggesting a simple dissociation of the precursor [M + Cl]− into a Cl− ion and a neutral M without fragmentation of the PIB backbones. However, structurally important product ions were produced from the corresponding [M + NH4]+ ions, allowing us to obtain valuable information on the arm‐length distributions of the PIBs containing aromatic initiator moiety. In addition, a model was developed to interpret the oligomer distributions and the number average molecular weights observed in DART‐MS for PIBs and other polymers of low molecular weight. Copyright © 2015 John Wiley & Sons, Ltd.
A technique for relative quantitation of cancer biomarkers in formalin‐fixed, paraffin‐embedded (FFPE) tissue using stable‐isotope‐label based mass spectrometry imaging (SILMSI)
Authors: Wang Hong , DeGnore Jon P. , Kelly Brian D. , True Jan , Garsha Karl , Bieniarz Christopher
Published: July 2015

We developed a novel technique for the relative quantitation of pairs of cancer biomarkers in formalin‐fixed paraffin‐embedded (FFPE) tissue. The method utilizes stable isotope labeled (SIL) chromogens deposited during the standard immunohistochemistry (IHC) tissue staining process. The labeled chromogens are precipitated on tissue enzymatically using the standard IHC protocols. The tissue is then imaged with matrix‐free laser desorption ionization time‐of‐flight mass spectrometry, and peak intensities of reporter ions are used to estimate the relative quantitation of protein biomarkers across the tissue. The relative abundance of two breast cancer biomarkers, estrogen receptor (ER) and progesterone receptor (PgR), were quantitated using their ratio of expression in xenograft models, and the ratios were found to be reproducible both within and across serial sections. The relative quantification of multiple biomarkers in situ across a single tissue section adds an additional dimension in cancer histological evaluation by allowing a visual and statistical assessment of tumor heterogeneity. Copyright © 2015 John Wiley & Sons, Ltd.
Theoretical investigation on confinement of ions in a cube‐shaped ion trap
Authors: Noshad Houshyar , Amouhashemi Majid
Published: July 2015

The confinement of ions in a cube‐shaped ion trap and the mathematical formalism governing the behavior of ions in the trap is investigated theoretically. Afterwards, the stability regions are computed using the fourth‐order Rung–Kutta method. Consequently, the influence of the direction of ions, injected into the trap from its center on the stability region, is numerically discussed. Moreover, the maximum angle of injection with respect to the vertical axis of the cube for which the ions could be confined in the trap without invoking any direct current component of voltage (henceforth referred to as limiting angle) was calculated. Strong linear correlation between the angle of injection and the ratio of the stability region areas is confirmed. A nonlinear feature of a cube‐shaped ion trap is demonstrated with a focus on the equations of motion for an ion confined into the trap. It is worthwhile to note that the stability region of our cubic ion trap, which has its own boundary conditions and electrodynamics, has been theoretically investigated for the first time. Besides, the limiting angle as well as the aforementioned strong linear correlation has not been reported in the literature previously. Copyright © 2015 John Wiley & Sons, Ltd.
Host genetic variants influencing the clinical course of hepatitis C virus infection
Authors: Matsuura Kentaro , Tanaka Yasuhito
Published: July 2015

The clinical course of hepatitis C virus (HCV) infection greatly differs in individuals. Various viral, host, and environmental factors influence the natural history of HCV infection. Recent genome‐wide association studies identified several host genetic factors influencing treatment efficacy or clinical course in HCV infection. A landmark discovery was that IFNL3‐IFNL4 variants are strongly associated with responses to interferon‐based treatment. Genetic variants in IFNL3‐IFNL4 as well as those in HLA class II loci influence the spontaneous clearance of acute HCV infection. Interestingly, these genetic variants also affect the activity of hepatitis, or disease progression in chronic hepatitis C. In addition, polymorphisms in apoptosis‐related genes such as RNF7, TULP1, and MERTK are associated with fibrosis progression, and DEPDC5 and MICA variants are associated with HCV‐related hepatocellular carcinoma. Understanding the genetic factors associated with the clinical course of HCV infection is essential for personalized treatment and surveillance of disease progression and hepatocellular carcinoma. J. Med. Virol. 88:185–195, 2016. © 2015 Wiley Periodicals, Inc.