bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel method to extract vanadium and chromium from vanadium slag using molten NaOH‐NaNO3 binary system
Authors: Liu Biao , Du Hao , Wang Shao‐Na , Zhang Yi , Zheng Shi‐Li , Li Lan‐Jie , Chen Dong‐Hui
Published: April 2012

A new method using NaOH‐NaNO3 binary melts to treat vanadium slag is proposed. Vanadium and chromium can be simultaneously extracted in the leaching processes. Under the optimum reaction conditions, the recovery of vanadium and chromium can reach 93.7% and 88.2% in 6 h, respectively. The kinetics investigation indicates that the decomposition of vanadium slag is controlled by mass transfer in product layer. During the reaction, NaOH is believed to provide basic media and facilitate the dissolution of acidic oxides. NaNO3 decomposes to produce a large amount of active oxygen species, such as O, , and O2−. NaOH intensifies the decomposition of NaNO3 to NaNO2, but inhibits further decomposition of NaNO2. NaNO3 can be regenerated by oxidation of NaNO2 using oxygen at high temperature. The apparent activation energy of NaNO2 oxidation in the temperature ranging from 350 to 450°C is 105.5 kJ/mol. © 2012 American Institute of Chemical Engineers AIChE J, 59: 541–552, 2013
An efficient solid‐phase synthesis of substituted benzofuran using selenium‐bound resin
Authors: Zhang Yin jun , Wang Yu guang
Published: April 2012

A very efficient solid‐phase synthesis of substituted benzofuran using polymer‐supported selenium resin is described. The advantages of the new method are good yields, high purity, straightforward operations, broad range and high diversity of products, lack of odor, and good stability of the resins. The easy work‐up procedure makes the method suitable for building parallel libraries. Copyright © 2012 John Wiley & Sons, Ltd.
Copolymerization of styrene and norbornene with β‐diketiminato nickel/methylaluminoxane catalytic system
Authors: Li Yongfei , Wu Qin , Shan Minyu , Gao Meili
Published: April 2012

Styrene–norbornene (S‐N) copolymerizations were carried out using β‐diketiminato nickel complexes CH{C(CF3)NAr}2NiBr (Ar = 2,6‐iPr2C6H3, 1; Ar = 2,6‐Me2C6H3, 2) in the presence of methylaluminoxane. The influence of the comonomer feed content and polymerization temperature on the conversion and composition of the copolymers with the catalytic system was investigated. An increase in the feed ratio of S/N led to an increase in the incorporated styrene content of the resulting copolymer. NMR characterization of the copolymers generated with the catalytic systems showed that the random S‐N copolymers are produced. Differential scanning calorimetric determination of the copolymers shows higher Tg values than polystyrene, and gel permeation chromatographic measurements have shown that the copolymers possess rather narrow molecular weight distributions, suggesting that the copolymerization take place at a single active site. Copyright © 2012 John Wiley & Sons, Ltd.
Studies on the mechanical, thermal, and morphological properties of poly(ether ether ketone)/poly(ether sulfone)/barium titanate nanocomposites: Correlation of experimental results with theoretical predictive models
Authors: Mandal Subhash , Alam Sarfaraz
Published: April 2012

In this study, mechanical, thermal, and morphological properties of the nanocomposites fabricated with the optimized blend of poly(ether ether ketone) (PEEK) and poly(ether sulfone) (PES) incorporated with nanobarium titanate (BT) were investigated. The optimized blend was based on the mechanical and thermal properties of the PEEK and PES in the ratio of 75 : 25 wt %. Nanoparticles were incorporated into the optimized blend with the help of twin‐screw extruder. The concentration of nano‐BT was varied from 2 to 6 wt % (0.41–1.28 vol %). With the increase in the nanosized BT concentrations, the tensile strength, tensile modulus, and elongation at break increased, whereas the crystallinity of the nanocomposites calculated by using differential scanning calorimetry method was found to decrease marginally. Morphological studies were carried out using scanning electron microscopy. The nanocomposites were evaluated by using theoretical predictive models according to “Pukanszky model” applicable to tensile strength and “Takayanagi's model” and “Guth and Smallwood model” applicable to tensile modulus. Upper and lower boundary of Hashin–Shtrikman model as well as Paul's model, applicable to tensile modulus, were also used to compare the experimental data. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Facile prepared bis(carbazyl thiocarbonyl) disulfide as chain transfer agent for RAFT polymerization of methyl methacrylate
Authors: Liu Bin , Deng Liandong , Guo Chungang , Guo Ruiwei , Dong Anjie , Zhang Jianhua
Published: April 2012

The bis(thiocarbonyl) disulfide compounds are key intermediates for the preparation of the high‐performance reversible addition‐fragmentation chain transfer (RAFT) agents with 2‐cyanoprop‐2‐yl or its homologous group as R group. In this article, a synthetic method in water was developed to prepare high‐purity bis(carbazyl thiocarbonyl) disulfide (BCTD) based on a straightforward oxidation reaction using K3[Fe(CN)6] as the oxidant. This method was proved to be a convenient, economical, and eco‐friendly route to synthesize bis(thiocarbonyl) disulfides with high purity and high yield. Subsequently, the RAFT polymerizations of methyl methacrylate (MMA) have been studied by using BCTD and azobis(isobutyronitrile) (AIBN) to in situ generate RAFT agent 2‐cyanoprop‐2‐yl N‐carbazylcarbodithioate (CYCBD). After a very short initial nonliving phase, the polymerization exhibited typical living polymerization characteristics, including that the molecular weights of PMMA linearly increase with monomer conversions and PDI can remain in a relatively low range. The results further indicated that the ratio of BCTD to AIBN and the reaction temperature had a significant impact on the MMA polymerization, and the living features were most prominent when the ratio of BCTD to AIBN is in the range of 1–2 and polymerization temperature at 60°C. In addition, 1H‐NMR analysis and fluorescence spectroscopy of the resultant polymethyl methacrylate (PMMA) confirm the formation of carbazole end‐labeled PMMA chains due to CYCBD generated in situ by the reaction of BCTD with AIBN. This can offer an alternative and complementary route to obtain well‐defined polymers, especially for preparation of polymers with high molecular weight and a relatively low polydispersity. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Microporous network‐assisted formation of copper‐in‐polymer gradient composite film
Authors: Yang Bo , Tang Jianguo , Yang Peihua , Wang Yao , Liu Jixian , Liu Haiyan , Wang Rui , Huang Zhen , Liu Jingquan , Belfiore Laurence A.
Published: April 2012

In this article, a copper‐in‐polymer‐gradient composite film (CPGCF) was synthesized by electrochemical strategy via reducing a solvent‐swollen cathode film (SCF). The latex nanoparticles of a ternary copolymer including styrene, butyl acrylate, and acrylic acid structural units play the key role to form well‐graded copper distribution in this ternary copolymer matrix through the porous morphological structure developed by latex nanoparticle semimelt joining. The morphological structure along cross‐section of CPGCF includes three layers: (1) a dense copper layer in ternary copolymer matrix whose most outside was originally attached to cathode in electrochemical reactor, (2) a shrublike layer that grew from dense copper layer, and (3) a clear layer in which there is no obvious reduced copper phase whose most outside was originally contacted with liquid electrolyte medium in electrochemical reactor. As experimental aspects, the influences of emulsion polymerization conditions of ternary copolymer, predrying time and temperature of SCF, dc voltage in electrochemical reduction on CPGCF structure were investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Endothelial progenitor cells in diabetes mellitus
Authors: Menegazzo Lisa , Albiero Mattia , Avogaro Angelo , Fadini Gian Paolo
Published: April 2012

Diabetes mellitus is associated with an increased risk of cardiovascular disease due to its negative impact on the vascular endothelium. The damaged endothelium is repaired by resident cells also through the contribution of a population of circulating cells derived from bone marrow. These cells, termed endothelial progenitor cells (EPCs) are involved in maintaining endothelial homeostasis and contributes to the formation of new blood vessels with a process called postnatal vasculogenesis. The mechanisms whereby these cells allow for protection of the cardiovascular system are still unclear; nevertheless, consistent evidences have shown that impairment and reduction of EPCs are hallmark features of type 1 and type 2 diabetes. Therefore, EPC alterations might have a pathogenic role in diabetic complications, thus becoming a potential therapeutic target. In this review, EPC alterations will be examined in the context of macrovascular and microvascular complications of diabetes, highlighting their roles and functions in the progression of the disease. © 2012 International Union of Biochemistry and Molecular Biology, Inc.
Membrane microdomains in immunity: Glycosphingolipid‐enriched domain‐mediated innate immune responses
Authors: Iwabuchi Kazuhisa , Nakayama Hitoshi , Masuda Hiromi , Kina Katsunari , Ogawa Hideoki , Takamori Kenji
Published: April 2012

Over the last 30 years, many studies have indicated that glycosphingolipids (GSLs) expressed on the cell surface may act as binding sites for microorganisms. Based on their physicochemical characteristics, GSLs form membrane microdomains with cholesterol, sphingomyelin, glycosylphosphatidylinositol (GPI)‐anchored proteins, and various signaling molecules, and GSL‐enriched domains have been shown to be involved in these defense responses. Among the GSLs, lactosylceramide (LacCer, CDw17) can bind to various microorganisms. LacCer is expressed at high levels on the plasma membrane of human neutrophils, and forms membrane microdomains associated with the Src family tyrosine kinase Lyn. LacCer‐enriched membrane microdomains mediate superoxide generation, chemotaxis, and non‐opsonic phagocytosis. Therefore, LacCer‐enriched membrane microdomains are thought to function as pattern recognition receptors (PRRs) to recognize pathogen‐associated molecular patterns (PAMPs) expressed on microorganisms. In contrast, several pathogens have developed infection mechanisms using membrane microdomains. In addition, some pathogens have the ability to avoid degradation by escaping from the vacuolar compartment or preventing phagosome maturation, utilizing membrane microdomains, such as LacCer‐enriched domains, of host cells. The detailed molecular mechanisms of these membrane microdomain‐associated host‐pathogen interactions remain to be elucidated. © 2012 International Union of Biochemistry and Molecular Biology, Inc.
Child Protection Peer Review for Paediatricians
Authors: Thomas Amanda , Mott Alison
Published: April 2012

Key Practitioner Messages

Peer review involves a group of peers engaged in a discussion and providing an opinion on an individual's case that the individual can accept or reject while retaining ultimate responsibility for providing their opinion.

Each health organisation employing paediatricians working in child protection should establish peer review processes in line with the recommendations and standards contained within this document and RCPCH Peer Review in Safeguarding (May 2012).
Evaluation of the predictive power of biplot axes to automate the construction and layout of biplots based on the accuracy of direct readings from common outputs of multivariate analyses: 1. application to principal component analysis
Authors: Rui Alves M.
Published: April 2012

Predictive biplots, as developed by J.C. Gower and coworkers, can be a very useful tool to aid the interpretation of the outcomes of multivariate analyses. This paper covers a statistical methodology that enables the automation of the construction of predictive biplots, as well as an R function, AutoBiplots.PCA( ), which applies the methodology to principal components analysis. A case study based on the sensory analysis of coffees is used to illustrate the methodology as well as the outputs of the R function.

The method relies on the definition of a variable's mean standard predictive error, mspe, as the degree of accuracy in the process of predicting the original values from the biplots, which is compared with a predefined tolerance value (Taxis) to decide if the correspondent biplot axis is drawn in the biplot. Standard predictive errors, spe, are calculated for each unit in relation to each biplot axis in each two‐dimensional plot and are compared with a predefined tolerance value (Tunits) to decide which units shall be faced as outliers. The R function automates the process, enabling the user to decide on the degree of precision of the actual analysis.

Besides providing a solution for the automatic production of predictive biplots, the methodology offers new insights for the interpretation of multivariate analyses outputs on the basis of a sound principle, the degree of precision of the analysis. This provides an automatic way for the selection of variables that explain latent dimensions and also helps in deciding on the number of important latent dimensions for model developments. Copyright © 2012 John Wiley & Sons, Ltd.
Chemometric approach to chromatic spatial variance. Case study: patchiness of the Skyros wall lizard
Authors: Brydegaard Mikkel , Runemark Anna , Bro Rasmus
Published: April 2012

In this paper, we demonstrate how to take advantage of the large number of spatial samples provided by commercial multispectral RGB imagers. We investigate the possibility to use various multidimensional histograms and probability distributions for decomposition and predictive models. We show how these methods can be used in an example using images of different Skyros wall lizards and demonstrate improved performance in prediction of color morph compared with traditional parameterization techniques of spatial variance. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and Theoretical Study of Intramolecular Hydrogen Bond at Two Possible Positions in Pyrazolo[1,2‐b]phthalazine
Authors: Yoosefian M. , Raissi H. , Davamdar E. , Esmaeili A. A. , Azaroon M.
Published: April 2012

Properties of dimethyl 3‐(alkylamino)‐5,10‐dioxo‐5,10‐dihydro‐1H‐pyrazolo[1,2‐b]phthalazine‐1,2‐dicarboxylate and its derivatives were studied by means ofab initiomethod. NO2derivative of title compound was synthesized and the nature of its intramolecular hydrogen bond (HB) was investigated. Furthermore, the topological properties of the electron density distributions for NH···O intramolecular bridges were analyzed in terms of the Bader theory of atoms in molecules (AIM). The electron density (ρ) and Laplacian (∇2ρ) properties, estimated by AIM calculations, indicated that O···H bond possesses low ρ and positive ∇2ρvalues which are in agreement with electrostatic character of the HBs, whereas NH bonds have covalent character (∇2ρ<0). Moreover, steric effect of thet‐Bu group on structure and topological parameters of pyrazolo[1,2‐b]phthalazine conformers was studied. Finally, the powerful method of Espinosa was used to obtain the H‐bond energy.
Spectral Characterization and Antimicrobial Activity of Some Schiff Bases Derived from 4‐Methyl‐2‐aminophenol
Authors: Gürbüz Demet , Cinarli Adem , Tavman Aydin , Birteks?z A. Seher
Published: April 2012

A series of N‐(5‐methyl‐2‐hydroxyphenyl)‐(2/3/4/5‐substituted)‐benzaldimines (I–XIII) were synthesized using appropriate synthetic route. Their structures were characterized by FT‐IR, UV‐Visible, ESI‐MS, 1H‐ and 13C‐NMR spectroscopic techniques and analytical methods. The crystal structure of N‐(5‐methyl‐2‐hydroxyphenyl)‐3,4‐dimethoxybenzaldimine (XIII) was determined by X‐ray diffraction at room temperature. Relationship between the melting points and the structures of the compounds were examined. Antibacterial activities of the compounds were evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus mirabilis. Antifungal activities were reported for Candida albicans. Some of the Schiff bases showed considerable antimicrobial activity against S. aureus and C. albicans.
Liquid Crystalline Behaviours of the Complexes Based on 1,3,4‐Oxadiazole Derivative and Benzoic Acid
Authors: Zhao Chengxiao , Wang Haitao , Ran Xia , Bai Binglian , Zhang Yan , Li Min
Published: April 2012

A non‐liquid crystal compound (4‐POXD‐6) containing the 1,3,4‐oxadiazole group and pyridyl (py) group was synthesized. And a series of supramolecular mesogenic complexes were obtained by mixing 4‐POXD‐6 and 4‐alkoxybenzoic acids (Cn, n=6, 8, 12). The liquid crystalline properties of 4‐POXD‐6/Cn (n=6, 8, 12) were investigated by means of differential scanning calorimetry, polarized optical microscopy, and wide‐angle X‐ray diffraction. It was found that 4‐POXD‐6/Cn (6, 8) display monotropic nematic and smectic A phases, while 4‐POXD‐6/C12 exhibits a SmX phase in the heating process and a SmA phase in the cooling run. Variable‐temperature FTIR spectroscopic studies revealed hydrogen bonds existed in both crystalline and liquid crystalline phases.
Dehydrogenation of Propane to Propylene in the Presence of CO2 over Steaming‐treated HZSM‐5 Supported ZnO
Authors: Zhang Fan , Miao Changxi , Yue Yinghong , Hua Weiming , Gao Zi
Published: April 2012

Dehydrogenation of propane to propylene over zinc oxide catalysts supported on steaming‐treated HZSM‐5 in the presence of CO2 has been investigated. The highest catalytic performance can be achieved on the 5%ZnO/HZSM‐5(650) catalyst with the HZSM‐5 support steaming at 650°C, which allows the maximum propylene yields of 29.7% and 20.3% at the initial and steady states, respectively, in the catalytic dehydrogenation of propane at 600°C. The superior catalytic performance of this catalyst can be attributed to high dispersion of ZnO and appropriate Br?nsted acidity of the HZSM‐5(650) support. The catalytic stability is enhanced by the addition of CO2 to the feed gas due to the suppression of coke formation.
An Improved Method for Synthesizing LiV3O8 Nanorods
Authors: Sun Junli , Zhao Min
Published: April 2012

This paper reports on the synthesis, characterization and electrochemical performance of LiV3O8 nanorods which were prepared through a very facile hydrothermal route. The diameters of the LiV3O8 nanorods are about 150 nm. The morphology of LiV3O8 can be controlled by adjusting the reaction conditions such as the reaction time and temperature. Electrochemical measurements reveal that the as‐prepared LiV3O8 nanorods display high initial discharge capacities (292.5 mA·hg−1) and excellent cyclability. This result indicates that the nanorods are a promising cathode candidate material for lithium batteries.
Microwave Irradiation for Accelerating Synthesis of Diarylimidizo[1,5‐a]pyrimidine Based on Isoflavones
Authors: Zhang Zunting , Zhang Pengfei , Kang Taoying , Zhu Mulin
Published: April 2012

Microwave irradiation was used to accelerate the cyclocondensation of isoflavones and 5‐amino‐1H‐imidazole‐4‐carboxamide in the presence of sodium hydroxide to produce 3,4‐diphenyl‐imidazo[1,5‐a]pyrimidines in good to moderate yields.
A Sustainable Synthesis of 2‐Benzoxazyl and 2‐Benzothiazyl Ketones from Alkynyl Bromides and 2‐Amino(thio)phenols Promoted by a Recyclable Catalytic System
Authors: Cui Liangyan , He Yan , Fan Xuesen
Published: April 2012

An environmentally and economically sustainable synthesis of 2‐benzoxazyl ketones and 2‐benzothiazyl ketones through FeCl3·6H2O catalyzed tandem reactions of alkynyl bromides with 2‐amino(thio)phenols in [bmim]BF4 has been developed. Remarkable advantages of this new synthetic strategy include high efficiency, readily available starting materials, and recyclable catalyst and reaction medium.
An Efficient Palladium and Bis(2‐pyridylmethyl)amine‐based System for Suzuki‐Miyaura Cross‐Coupling under Aqueous and Aerobic Condition
Authors: Yu Jianjun , Wang Limin , Liu Mingtao , Qiu Jun , Shen Qiang , Fang Lei , Tang Jun
Published: April 2012

A novel PdCl2/bis(2‐pyridylmethyl)amine‐based ligand (1) catalytic system, which is water‐soluble and air‐stable, has been successfully synthesized and applied for Suzuki‐Miyaura cross‐coupling reaction. In the presence of catalytic amount of PdCl2/1 system, arylboronic acids can couple with a wide range of aryl halides, including aryl bromides and aryl chlorides. The reactions proceed under mild conditions to give excellent yields, and a wide range of functionalities is tolerated.
Synthesis, Crystal Structures and Electrochemical Properties of Complexes [M(ImH)4(tfbdc)(H2O)] (M=Co, Ni)
Authors: Wu Yujuan , Yu Lili , Cheng Meiling , Han Wei , Wang Lidong , Guo Xue , Liu Qi
Published: April 2012

The title complexes [M(ImH)4(tfbdc)(H2O)] (1: M=Co; 2: M=Ni) (ImH=imidazole, tfbdc=2,3,5,6‐tetrafluoroterephthalate) were synthesized by the reaction of M(OAc)2·4H2O, H2tfbdc and ImH in water solution. The complexes were characterized by elemental analysis, IR spectra, thermogravimetric analysis, cyclic voltammetry and X‐ray single crystal structure analysis. Structural analysis reveals that 1 and 2 possess isostructure: monoclinic, P21/c, Z=4. M(II) ion in complexes 1 and 2 has a distorted octahedral geometry coordinated by one oxygen atom from water, one oxygen atom from tfbdc2− and four nitrogen atoms from ImHs. They are discrete zero‐dimensional molecular complexes. And the adjacent monomeric components are connected by hydrogen bonds to form a supramolecule. Electrochemical properties of the complexes 1 and 2 show that electron transfer of M(II) between M(III) in electrolysis is a quasi‐reversible process.
Microwave‐assisted Ionothermal Synthesis and Characterization of Zeolitic Imidazolate Framework‐8
Authors: Yang Lisha , Lu Huimin
Published: April 2012

The zeolitic imidazolate framework‐8 (ZIF‐8) was successfully synthesized using ionic liquids as structure‐directing agent under microwave irradiation. Ionic liquids are green solvents with low vapour pressure and good thermal stability. They are appropriate templates for microporous materials and ideal microwave absorbers. The microwave‐assisted ionothermal synthesis applied in this paper was expected to be a promising method for the preparation of microporous materials. Results showed that the as‐synthesized samples (300–500 nm in diameter) could be synthesized in a short time (60 min) and possessed regular morphology, stable structure and high thermal stability (up to 720°C in argon atmosphere). Nitrogen adsorption‐desorption test illustrated that samples produced by microwave heating had a higher surface area. Carbon dioxide adsorption test indicated that the samples synthesized by microwave heating had better carbon dioxide adsorption ability than those by conventional heating.
A Novel Protocol for the Regioselective Bromination of Primary Alcohols in Unprotected Carbohydrates or Glycosides
Authors: Xue Weihua , Zhang Lifen
Published: April 2012

The regioselective and efficient bromination of primary hydroxyl groups in unprotected carbohydrates or glycosides is successfully achieved by using (chloro‐phenylthio‐methylene)dimethylammoniumchloride (CPMA) in the presence of tetrabutylammonium bromide (TBAB) in dry DMF.
Competitiveness as a Strategic Outcome of Corporate Social Responsibility
Authors: Marín Longinos , Rubio Alicia , de Maya Salvador Ruiz
Published: April 2012

There is a gap in the literature concerning the effects of corporate social responsibility (CSR) on corporate strategy. This study analyses the influence of CSR on competitiveness as a strategic dimension of companies. It addresses the conditions under which CSR has a positive influence on competitiveness through testing the moderator effect of corporate strategy, size, and industry. Based on an empirical study of 144 companies, the results show a positive effect of CSR on competitiveness, which is stronger for large companies and for companies that follow a proactive (vs reactive) strategy, while no differences appear between service and manufacturing industries. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
The impact of effective continuous positive airway pressure on homeostasis model assessment insulin resistance in non‐diabetic patients with moderate to severe obstructive sleep apnea
Authors: Yang Dan , Liu Zhihong , Yang Haixing
Published: April 2012

Previous studies on the effects of continuous positive airway pressure (CPAP) on homeostasis model assessment insulin resistance (HOMA‐IR) in obstructive sleep apnea patients have yielded conflicting results. Therefore, we conducted this meta‐analysis to evaluate the impact of effective CPAP on HOMA‐IR in non‐diabetic patients with moderate to severe obstructive sleep apnea. We searched PubMed, HighWire Press, Ovid Medline (R), Cochrane library and EMBASE before December 2011 on original English language studies. The data on HOMA‐IR and body mass index (BMI) were extracted from these studies. As compared with baseline values, 8 to 24 weeks of effective CPAP (>4 h/night) treatment significantly reduced HOMA‐IR by an average of 0.75(95% CI, from −0.96 to −0.53; p < 0.001). However, in subjects with irregular CPAP (<4 h/night), this effect was not observed (−0.22; 95%CI, from −2.24 to 1.80; p = 0.83). There were no intervention‐related changes in BMI in both regular and irregular CPAP. Our analysis showed that 8 to 24 weeks of effective CPAP could significantly improve HOMA‐IR in non‐diabetic patients with moderate to severe obstructive sleep apnea, while no significant changes in BMI were detected. Further large scale, randomized and controlled trials are needed to evaluate the longer treatment and its possible effects on weight control and cardiovascular disease. Copyright © 2012 John Wiley & Sons, Ltd.
Obesity is associated with activated and insulin resistant immune cells
Authors: Viardot A. , Heilbronn L. K. , Samocha‐Bonet D. , Mackay F. , Campbell L. V. , Samaras K.
Published: April 2012

Background

Obesity and type 2 diabetes mellitus are characterized by insulin resistance and ‘low‐grade inflammation’; however, the pathophysiological link is poorly understood. To determine the relative contribution of obesity and insulin resistance to systemic ‘inflammation’, this study comprehensively characterized circulating immune cells in different grades of obesity.

Methods

Immune cell phenotypes and activation status were analysed by flow cytometry cross‐sectionally in morbidly obese (n = 16, body mass index (BMI) 42.2 ± 5.4 kg/m2), overweight (n = 13, BMI 27.4 ± 1.6 kg/m2) and normal weight (n = 12, BMI 22.5 ± 1.9 kg/m2) subjects.

Results

Obese, but not overweight subjects, had increased activation marker expression on neutrophils, monocytes, T‐lymphocytes and polarization of T helper cells towards a pro‐inflammatory type 1‐phenotype (Th1). Th1 numbers correlated positively with the degree of insulin resistance (homeostasis model assessment, p < 0.05). Lymphocytes from obese subjects showed reduced insulin‐stimulated AKT‐phosphorylation in vitro. Supra‐physiological insulin concentrations did not affect T‐cell differentiation, which under normal circumstances would promote an anti‐inflammatory T helper type 2‐phenotype.

Conclusions

These results show that morbid obesity is characterized by circulating immune cells that are activated and insulin resistant, with the T‐cell balance polarized towards a pro‐inflammatory Th1 phenotype. The loss of insulin‐induced suppression of inflammatory phenotypes in circulating immune cells could contribute to the systemic and adipose tissue inflammation found in morbid obesity. Copyright © 2012 John Wiley & Sons, Ltd.
Birth weight in newborn infants with different diabetes‐associated HLA genotypes in three neighbouring countries: Finland, Estonia and Russian Karelia
Authors: Peet Aleksandr , Kool Pille , Ilonen Jorma , Knip Mikael , Tillmann Vallo ,   for the DIABIMMUNE Study Group
Published: April 2012

Background

Human leukocyte antigen (HLA) genotypes associated with increased risk for type 1 diabetes mellitus (T1D) have been reported to be associated with increased birth weight. We set out to investigate the association between HLA haplotypes conferring risk for T1D and birth weight and search for possible differences in the strength of these associations among populations with contrasting incidence of T1D.

Methods

As a part of the EU‐funded DIABIMMUNE study, genotyping for the HLA haplotypes associated with T1D was performed in 8369 newborn infants from Estonia, Finland and Russian Karelia. Infants born before 35 gestational weeks, from mothers with diabetes, and multiple pregnancies were excluded. Relative birth weight, expressed in standard deviation scores, was estimated for each gestational week, sex and country. The standard deviation scores were calculated internally using the actual population studied. According to their HLA haplotypes, participants were divided into risk groups, and the distribution of birth weight between quartiles was analysed.

Results

We did not find any direct association between various HLA risk‐associated genotypes (HLA DR3‐DQ2/DR4‐DQ8, DR3‐DQ2/X or DR4‐DQ8/X) and birth weight. We observed a significant relationship between increased relative birth weight and the protective HLA‐DR2‐DQ6 and DR13‐DQ6 haplotypes. This association was significant only when these haplotypes were found together with the DR4‐DQ8 haplotype.

Conclusions

The previously reported association between HLA‐risk haplotypes for T1D and an increased birth weight was not confirmed. This suggests that the mechanisms behind the association between high birth weight and risk for T1D may be not directly HLA related. Copyright © 2012 John Wiley & Sons, Ltd.
Enrichment of edible oil with sea buckthorn by‐products using ultrasound‐assisted extraction
Authors: Chemat Farid , Périno‐Issartier Sandrine , Loucif Lynda , Elmaataoui Mohamed , Mason Timothy J.
Published: April 2012

Sea buckthorn (SBT) pomace, a by‐product of juice production, has been studied as a potential carotenoids source because such compounds are of great interest in the food industry. Ultrasound‐assisted extraction (UAE) has been used to improve the direct enrichment of edible oils (sunflower, rape seed, olive, and soya) with SBT carotenoids. These oils do not naturally contain carotenoids. After a preliminary study, a RSM has been used to maximize total carotenoid content of extracts and the influence of process variables on the UAE has been investigated. The results provided by the statistical analysis revealed that the optimized conditions were: sonication power of 0.67 W/g oil and a temperature of 35°C. The optimization parameters of this “green” process provide a greatly improved enrichment of the edible oil in terms of quantity and process time from 33.83 mg/L extract in 90 min obtained by conventional extraction to 51.64 mg/L extract in only 20 min by UAE. Ultrasound‐assisted carotenoids extraction from SBT by‐products appears to be a simple, rapid, and sustainable alternative to conventional procedures.

Practical applications: Improving the value of low quality edibles is important for the food, cosmetic, or nutraceutical industry. It is done by adding ingredients such as carotenoids which are extracted by hexane or other solvents. In this study we show an innovative application of a direct extraction by maceration of by‐products in edible oil without solvent and eliminating evaporation and extraction unit operations. Using ultrasound, full extractions can now be completed in minutes with high reproducibility, reducing the consumption of solvent, simplifying manipulation and work‐up, giving higher purity of the final product, eliminating post‐treatment of waste water, and consuming only a fraction of the fossil energy normally needed for a conventional extraction method such as Soxhlet extraction, maceration, or steam distillation.
Tabernaelegantinals: Unprecedented Cytotoxic Bisindole Alkaloids from Muntafara sessilifolia
Authors: Girardot Marion , Gadea Alice , Deregnaucourt Christiane , Deville Alexandre , Dubost Lionel , Nay Bastien , Maciuk Alexandre , Rasoanaivo Philippe , Mambu Lengo
Published: April 2012

Bioassay‐guided fractionation of the stem bark of Muntafara sessilifolia has led to the isolation of six new vobasinyl‐iboga bisindole alkaloids, tabernaelegantinals A, B and E, and (3′R)‐hydroxytabernaelegantines A, C and D, together with six known monomeric indole and two bisindole alkaloids. The structures of these alkaloids were established by NMR and MS analysis. The bisindole alkaloids demonstrated cytotoxicity against the human lung MRC‐5 and rat skeletal muscle L‐6 cell lines whereas only one monomeric indole alkaloid was found to be cytotoxic. Tabernaemontanine acetate was found to be selectively antiplasmodial against the chloroquine‐resistant strain FcB1 of Plasmodium falciparum (5.3 μM IC50) over mammalian cell lines (selectivity index > 45). The tabernaelegantinals share an unprecedented α‐amino aldehyde moiety, the biosynthetic origin of which is discussed.
Direct Aldol Reaction of Pyruvic Derivatives: Catalytic Attempt To Synthesize Ulosonic Acids
Authors: El‐Sepelgy Osama , Schwarzer Darius , Oskwarek Piotr , Mlynarski Jacek
Published: April 2012

The catalytic asymmetric aldol reaction of pyruvic aldehyde dimethyl acetal and 2‐acetylthiazole with sugar aldehydes is demonstrated to be the key step in the synthesis of 3‐deoxy‐2‐ulosonic acids. Efficient and stereoselective pyruvate aldol reactions are catalyzed by metal‐based chiral Trost and Shibasaki catalysts. The presented synthetic methodology mimics aldolase‐catalyzed reactions by direct activation of C3 pyruvate equivalents with the use of metal‐based chiral catalysts en route to the synthesis of 2‐keto‐3‐deoxy‐D‐glucosonic acid and 3‐deoxy‐D‐manno‐2‐octulosonic acid derivatives.
Modification of γ‐secretase by nitrosative stress links neuronal ageing to sporadic Alzheimer's disease
Authors: Guix Francesc X. , Wahle Tina , Vennekens Kristel , Snellinx An , Chávez‐Gutiérrez Lucía , Ill‐Raga Gerard , Ramos‐Fernandez Eva , Guardia‐Laguarta Cristina , Lleó Alberto , Arimon Muriel , Berezovska Oksana , Muñoz Francisco J. , Dotti Carlos G. , De Strooper Bart
Published: April 2012

Inherited familial Alzheimer's disease (AD) is characterized by small increases in the ratio of Aβ42 versus Aβ40 peptide which is thought to drive the amyloid plaque formation in the brain of these patients. Little is known however whether ageing, the major risk factor for sporadic AD, affects amyloid beta‐peptide (Aβ) generation as well. Here we demonstrate that the secretion of Aβ is enhanced in an in vitro model of neuronal ageing, correlating with an increase in γ‐secretase complex formation. Moreover we found that peroxynitrite (ONOO−), produced by the reaction of superoxide anion with nitric oxide, promoted the nitrotyrosination of presenilin 1 (PS1), the catalytic subunit of γ‐secretase. This was associated with an increased association of the two PS1 fragments, PS1‐CTF and PS1‐NTF, which constitute the active catalytic centre. Furthermore, we found that peroxynitrite shifted the production of Aβ towards Aβ42 and increased the Aβ42/Aβ40 ratio. Our work identifies nitrosative stress as a potential mechanistic link between ageing and AD.
Cognitive Set‐Shifting in Anorexia Nervosa
Authors: Shott Megan E. , Filoteo J. Vincent , Bhatnagar Kelly A.C. , Peak Nicole J. , Hagman Jennifer O. , Rockwell Roxanne , Kaye Walter H. , Frank Guido K.W.
Published: April 2012

Objective

Adult anorexia nervosa (AN) is associated with inefficient cognitive flexibility and set‐shifting. Whether such inefficiencies also characterize adolescent AN is an important area of research.

Method

Adolescents with AN and matched controls were administered a computerized task that required initial learning of an explicit rule using corrective feedback and learning of a new rule after a set number of trials. Adult patients with AN and controls were also examined.

Results

Adolescents with AN did not differ from matched controls with respect to set‐shifting cost (decrease in performance after rule change), whereas adults with AN had significantly greater set‐shifting cost compared with controls.

Discussion

This study suggests that set‐shifting inefficiencies may not be a vulnerability factor for AN development in adolescents with AN, but might become an important aspect of the disorder at later age, and could point towards developmental neurobiologic brain changes that could affect AN at different ages. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Comparison of Obese and Nonobese Individuals with Binge Eating Disorder: Delicate Boundary Between Binge Eating Disorder and Non‐Purging Bulimia Nervosa
Authors: Carrard Isabelle , der Linden Martial Van , Golay Alain
Published: April 2012

Objective

To compare obese and nonobese individuals with binge eating disorder (BED) on demographic data, illness history, eating disorders and psychological health.

Methods

This study used baseline data from a randomized controlled study on the efficacy of an online cognitive behavioural self‐help treatment. Seventy‐four women aged between 18 and 60 years were recruited in the community. They had to meet full or subthreshold diagnostic criteria for BED according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.

Results

Forty per cent of the sample had a body mass index higher than 30 kg/m2. Mean age and severity of eating disorders were similar between obese and nonobese individuals. A statistically significant difference emerged regarding dietary restraint, with nonobese BED individuals exhibiting higher scores than obese BED individuals.

Conclusions

Dietary restraint might be one of the factors explaining body mass index differences among BED individuals. This raises the question of the boundary between non‐purging bulimia nervosa and BED in nonobese people. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Identification of MicroRNAs associated with early relapse after nephrectomy in renal cell carcinoma patients
Authors: Slaby Ondrej , Redova Martina , Poprach Alexandr , Nekvindova Jana , Iliev Robert , Radova Lenka , Lakomy Radek , Svoboda Marek , Vyzula Rostislav
Published: April 2012

Renal cell carcinoma (RCC) is the most common neoplasm of adult kidney. One of the important unmet medical needs in RCC is prognostic biomarker enabling identification of patients at high risk of relapse after nephrectomy. MicroRNAs (miRNAs) constitute a robust regulatory network with posttranscriptional regulatory efficiency for almost one‐half of human coding genes, including oncogenes and tumor suppressors. To identify potential prognostic miRNAs, we analyzed expression profiles in tumors of different prognostic groups of RCC patients. Seventy‐seven patients with clear cell RCC and detailed clinicopathological data were enrolled in a single‐center study. Global miRNA expression profiles were obtained by use of TaqMan Low Density Arrays (754 parallel quantitative reverse‐transcriptase polymerase chain reactions (qRT‐PCR) reactions). For validation of identified miRNAs individual miRNA TaqMan assays were performed in an independent group of patients. We identified tumor relapse‐signature based on the expression of 64 miRNAs differentially expressed between relapse‐free RCC patients and RCC patients who developed relapse (20 miRNAs were increased, 44 miRNAs were decreased). In the validation phase of the study, we successfully confirmed that expression levels of miR‐143, miR‐26a, miR‐145, miR‐10b, miR‐195, and miR‐126 are lower in the tumors of RCC patients who developed tumor relapse, moreover, the lowest levels of these miRNAs we observed in primary metastatic tumors. By using Kaplan–Meier analysis, we identified that miR‐127‐3p, miR‐145, and miR‐126 are significantly correlated with relapse‐free survival of nonmetastatic RCC patients. If further validated, we suggest that identified miRNAs might be used for identification of RCC patients at high risk of early relapse after nephrectomy in clinical practice. © 2012 Wiley‐Periodicals, Inc.
Ensembles of human MTL neurons “jump back in time” in response to a repeated stimulus
Authors: Howard Marc W. , Viskontas Indre V. , Shankar Karthik H. , Fried Itzhak
Published: April 2012

Episodic memory, which depends critically on the integrity of the medial temporal lobe (MTL), has been described as “mental time travel” in which the rememberer “jumps back in time.” The neural mechanism underlying this ability remains elusive. Mathematical and computational models of performance in episodic memory tasks provide a specific hypothesis regarding the computation that supports such a jump back in time. The models suggest that a representation of temporal context, a representation that changes gradually over macroscopic periods of time, is the cue for episodic recall. According to these models, a jump back in time corresponds to a stimulus recovering a prior state of temporal context. In vivo single‐neuron recordings were taken from the human MTL while epilepsy patients distinguished novel from repeated images in a continuous recognition memory task. The firing pattern of the ensemble of MTL neurons showed robust temporal autocorrelation over macroscopic periods of time during performance of the memory task. The gradually‐changing part of the ensemble state was causally affected by the visual stimulus being presented. Critically, repetition of a stimulus caused the ensemble to elicit a pattern of activity that resembled the pattern of activity present before the initial presentation of the stimulus. These findings confirm a direct prediction of this class of temporal context models and may be a signature of the mechanism that underlies the experience of episodic memory as mental time travel. © 2012 Wiley Periodicals, Inc.
Investigating correlations between snowmelt and forest fires in a high latitude snowmelt dominated drainage basin
Authors: Semmens Kathryn Alese , Ramage Joan
Published: April 2012

High latitude drainage basins are experiencing increases in temperature higher than the global average, with snowmelt dominated basins most sensitive to effects in winter because of the snowpack's integration of these changes over the season. This may influence the timing of snowmelt onset, the melt‐refreeze period and snowpack accumulation resulting in changes in spring runoff, associated flooding and drought conditions later in the year, possibly enhancing forest fire potential. Large burned areas cleared of vegetation change discharge dynamics and may affect snowmelt characteristics and discharge in subsequent seasons. Correlations are tested by comparing forest fire occurrence with spring melt onset, the end of the melt‐refreeze period (after which snow rapidly depletes) and early snowmelt events. Snow characteristics are derived from brightness temperature (Tb) data from the Advanced Microwave Scanning Radiometer for EOS (AMSR‐E) for 2003–2010. Dates of melt onset, end of melt‐refreeze and early melt events are defined with Tb and diurnal amplitude variation thresholds. Areas and intensities of forest fires are from the Moderate Resolution Imaging Spectroradiometer (MODIS) thermal anomaly data (MOD14), and all data are mapped to an Equal‐Area Scalable Earth Grid to assess spatial correlations. Earlier melt onset and end of melt‐refreeze are found in years and areas of high forest fire occurrence by comparing high (2004–2005) and low (2006–2007) fire years in the Porcupine sub‐basin of the Yukon River in northeastern Alaska and the Yukon Territory. The burned areas also correlate with relatively later melt onset and later end of melt‐refreeze in subsequent low fire years. Copyright © 2012 John Wiley & Sons, Ltd.
International harmonization of models for selecting less toxic chemical alternatives: Effect of regulatory disparities in the United States and Europe
Authors: Lam Carl W , Aguirre Muskilda P , Schischke Karsten , Nissen Nils F , Ogunseitan Oladele A , Schoenung Julie M
Published: April 2012

The desire to reduce human exposure to toxic chemicals associated with consumer products that are marketed globally demands the creation of comparative toxicity assessment tools that are based on uniform thresholds of acceptable risks and guidelines for materials use across international boundaries. The Toxic Potential Indicator (TPI) is a quantitative model based on European Union (EU) regulatory standards for toxicity and environmental quality. Here, we describe a version of TPI that we developed with US regulatory thresholds for environmental and human health impacts of toxic materials. The customized US-based TPI (USTPI) model integrates occupational permissible exposure limits (PELs), carcinogen categories based on the scheme of the International Agency for Research on Cancer (IARC), and median effect concentration for acute aquatic toxicity (EC50s). As a case study, we compare calculated scores for EU-based TPI (EUTPI) and USTPI for a large group of chemicals including 578 substances listed in the US Toxics Release Inventory (TRI). Statistical analyses show that the median difference between USTPI and EUTPI scores do not approximate to zero, implying a general discrepancy in TPI score results. Comparison of chemical ranking with Spearman's correlation coefficient suggests a positive but imperfect rank correlation. Although some discrepancies between EUTPI and USTPI may be explained by missing toxicity information in some regulatory categories, disparities between the 2 models are associated mostly with different input parameters, i.e., different regulatory thresholds and guidelines. These results demonstrate that regional differences in regulatory thresholds for material toxicity may compromise the ideals of international agreements, such as the Globally Harmonized System (GHS) of Classification and Labeling of Chemicals, and emphasis needs to be placed on eliminating inconsistencies in hazard assessment frameworks for substances. Integr Environ Assess Manag 2012; 8: 723–730. © 2012 SETAC