bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallization behavior of poly(p‐dioxanone)‐PU/montmorillonite nanocomposites prepared by chain‐extending reaction
Authors: Zhou Yan , Zhang Jing‐Jing , Niu Ying , Huang Cai‐Li , Yang Ke‐Ke 
Published: May 2012

AbstractOrgano‐modified montmorillonites and poly(p‐dioxanone) (PPDO) diol prepolymers were used to prepare Poly(p‐dioxanone)‐PU/organic montmorillonite (PPDO‐PU/OMMT) nanocomposites by chain‐extending reaction. The crystallization behavior and spherulitic morphology of PPDO‐PU/OMMT nanocomposites were investigated by WXRD, differential scanning calorimetry, and polarized optical microscopy. The results show that the regularity of the chain structure plays a dominant role during the crystallization process rather than that of OMMT content and its dispersion status in PPDO matrix. With similar molecular weight and same OMMT content, PPDO‐PU/OMMT nanocomposite, which derived from lower molecular weight PPDO prepolymer, exhibits lower crystallization rate, melting point, and crystallinity. The influence of the clay content on the crystallization behavior highly depends on its dispersing state. The nucleating effect of OMMT can be only observed at high loading percentage. For the nanocomposites with low clay loading percentage, the retarding effect of exfoliated platelets on the chain‐ordering into crystal lamellae became the key factor. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Patterns in species richness and assemblage structure of native mussels in the Upper Mississippi River
Authors: Zigler Steven J. , Newton Teresa J. , Davis Mike , Rogala James T. 
Published: May 2012

ABSTRACT

To evaluate patterns in mussel assemblages in the Upper Mississippi River (UMR), data from systematic surveys of mussels conducted in three large reaches (Navigation Pools 5, 6, and 18) from 2005–2007 were analysed.
Nonmetric multi‐dimensional scaling analyses and permutation tests indicated that assemblages differed among reaches. The mussel assemblage in Pool 18 was substantially different from the assemblage in Pool 5 and moderately different from the assemblage in Pool 6, whereas assemblages in Pools 5 and 6 were similar. Assemblages in broadly defined, flowing aquatic habitats did not substantially differ.
The dissimilarity of Pool 18 was primarily the result of Pool 18 having higher abundances of three Quadrula species (Q. quadrula, Q. pustulosa, and Q. nodulata), and lower abundances of Amblema plicata and Fusconaia flava.
Rarefaction analyses showed that species richness and species density were higher in Pool 18 compared with the other two pools.
Large‐scale patterns in mussel assemblages may be related to other longitudinal trends in the system including geomorphology, water quality, and abundances of fish species that serve as hosts for glochidial larvae.
The results suggest that management goals and actions in the UMR may need to account for important differences in mussel assemblages that occur among reaches. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Behcet's Disease with Active Uveitis: Detection of Serum Protein Biomarkers Using MALDI‐TOF‐MS
Authors: Wang Xin , Zhang Mei Fen , Xie Jing , Li Zhi Li , Wang Peng 
Published: May 2012

AbstractBehcet's Disease (BD) is a multisystem autoimmune disorder that lacks sensitive and specific diagnostic methods. The aim of this study was to identify potential biomarkers specific for BD and to establish a diagnostic model. Serum samples from patients with BD, Vogt‐Koyanagi‐Harada syndrome (VKH), and healthy controls (HC) were randomly divided into a training set (49 BD, 31 VKH, and 48 HC) and a testing set (13 BD, 10 VKH, and 11 HC). Proteomic mass spectra were generated by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS). Thirty‐nine differential m/z peaks associated with BD were identified, and the m/z peaks at 1,644, 1,711, 2,023, 4,347, 6,628, and 8,559 were used to construct a model for the diagnosis of BD. This diagnostic model can distinguish BD from non‐BD controls with a sensitivity of 83.67% (41/49) and a specificity of 89.87% (71/79). BD was detected in our blinded testing set with good sensitivity and specificity of 84.6 and 90.48%, respectively. The results suggested that proteomic fingerprint technology combining magnetic beads with MALDI‐TOF‐MS has potential for the diagnosis of BD. The biomarker classification model was suitable for preliminary identification of BD and could potentially serve as a useful tool for BD diagnosis and differential diagnosis. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
Interconversion of Metallabenzenes and Cyclic η2‐Allene‐Coordinated Complexes
Authors: Lin Ran , Zhao Jing , Chen Hanyu , Zhang Hong , Xia Haiping 
Published: May 2012

AbstractTreatment of the osmabenzene [Os{CHC(PPh3)CHC(PPh3)CH} Cl2(PPh3)2]Cl (1) with excess 8‐hydroxyquinoline produces monosubstituted osmabenzene [Os{CH C(PPh3) CHC(PPh3)CH}(C9H6NO)Cl(PPh3)]Cl (2) or disubstituted osmabenzene [Os{CHC(PPh3)CHC(PPh3)CH} (C9H6NO)2]Cl (3) under different reaction conditions. Osmabenzene 2 evolves into cyclic η2‐allene‐coordinated complex [Os{CHC(PPh3)CH=(η2‐CCH2)}(C9H6NO)(PPh3)2]Cl (4) in the presence of excess PPh3 and NaOH, presumably involving a PC bond cleavage of the metallacycle. Reaction of 4 with excess 8‐hydroxyquinoline under air affords the SNAr product [(C9H6NO)Os{CHC(PPh3)CHCHC} (C9H6NO)(PPh3)]Cl (5). Complex 4 is fairly reactive to a nucleophile in the presence of acid, which could react with water to give carbonyl complex [Os{CHC(PPh3)CHCH2}(C9H6NO) (CO)(PPh3)2]Cl (6). Complex 4 also reacts with PPh3 in the presence of acid and results in a transformation to [Os {CHC(PPh3)CHCHC}(C9H6NO)Cl (PPh3)2]Cl (7) and [Os{CHC(PPh3) CH=(η2‐CCH(PPh3))}(C9H6NO) Cl(PPh3)]Cl (8). Further investigation shows that the ratio of 7 and 8 is highly dependent on the amount of the acid in the reaction.
Does obesity modify the association of supplemental folic acid with folate status among nonpregnant women of childbearing age in the United States?
Authors: Tinker Sarah C. , Hamner Heather C. , Berry Robert J. , Bailey Lynn B. , Pfeiffer Christine M. 
Published: May 2012

AbstractBACKGROUNDObesity is associated with an increased risk of having a pregnancy affected by a neural tube defect (NTD). It is not clear whether the amount of folic acid required by obese women to protect against NTDs is the same as that for nonobese women.METHODSWe analyzed data from the National Health and Nutrition Examination Survey, representative of the noninstitutionalized civilian U.S. population, to assess whether body mass index (BMI; normal weight, overweight, and obese categories) modified the association between supplemental folic acid intake and folate status. We estimated the geometric mean concentration among nonpregnant women of childbearing age (15–44 years) during the postfortification period of: serum folate (2003–2008); red blood cell (RBC) folate (2007–2008); and plasma total homocysteine (tHcy; 2003–2006), adjusted for age, race and ethnicity, and total dietary folate expressed as dietary folate equivalents for strata of supplement use and BMI.RESULTSBMI was inversely associated with serum folate among women who did not use supplements containing folic acid; no differences between women in different BMI categories were observed among supplement users. Regardless of supplement use, obese women had the highest RBC folate concentrations. There were no differences in tHcy by BMI, regardless of supplement use.CONCLUSIONSThese results do not support a straightforward modification of the relationship between supplemental folic acid intake and folate status by BMI. In this population, BMI may affect the body distribution of folate, as reflected by lower serum and higher RBC folate levels in obese women who do not use supplements. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
Three‐Dimensional Pharmacophore Design and Biochemical Screening Identifies Substituted 1,2,4‐Triazoles as Inhibitors of the Annexin A2–S100A10 Protein Interaction
Authors: Reddy Tummala R. K. , Li Chan , Fischer Peter M. , Dekker Lodewijk V. 
Published: May 2012

AbstractProtein interactions are increasingly appreciated as targets in small‐molecule drug discovery. The interaction between the adapter protein S100A10 and its binding partner annexin A2 is a potentially important drug target. To obtain small‐molecule starting points for inhibitors of this interaction, a three‐dimensional pharmacophore model was constructed from the X‐ray crystal structure of the complex between S100A10 and annexin A2. The pharmacophore model represents the favourable hydrophobic and hydrogen bond interactions between the two partners, as well as spatial and receptor site constraints (excluded volume spheres). Using this pharmacophore model, UNITY flex searches were carried out on a 3D library of 0.7 million commercially available compounds. This resulted in 568 hit compounds. Subsequently, GOLD docking studies were performed on these hits, and a set of 190 compounds were purchased and tested biochemically for inhibition of the protein interaction. Three compounds of similar chemical structure were identified as genuine inhibitors of the binding of annexin A2 to S100A10. The binding modes predicted by GOLD were in good agreement with their UNITY‐generated conformations. We synthesised a series of analogues revealing areas critical for binding. Thus computational predictions and biochemical screening can be used successfully to derive novel chemical classes of protein–protein interaction blockers.
Evolution of Late Transition‐Metal‐Catalyzed Intermolecular Reductive Coupling Reaction of [60]Fullerene and N‐Sulfonylaldimines: Competing Formation of Hydrobenzylated [60]Fullerenes and 1,2‐Dihydrofullerene
Authors: Rajeshkumar Venkatachalam , Chuang Shih‐Ching 
Published: May 2012

AbstractA system based on late transition‐metal halides, phosphanes, water, and reducing agents in 1,2‐dichlorobenzene can efficiently catalyze the intermolecular reductive coupling of [60]fullerene with N‐sulfonylaldimines to afford novel 1,2‐hydrobenzylated [60]fullerene derivatives. We found that both group VII B metals (cobalt, rhodium, iridium) and group VIII B metals (nickel, palladium, platinum) perform this coupling reaction. A control experiment in the absence of aldimines produced C60H2, which showed that the reaction might proceed via a [60]fullerene metal complex [M(η2‐C60)(ligand)]. An isotope labeling experiment with D2O as deuterium source resulted in deuterioaryzilation with deuterium bonded to the sp3‐carbon of C60, providing evidence of a five‐membered azametallacycle intermediate. Evaluation of the scope of reductive coupling reaction with versatile aldimines gave access to the hydroaryzilation products. All the reductive coupling products were completely characterized by IR and NMR spectroscopy and ESI mass spectrometry. A possible reaction mechanism based on these results is proposed. This discovery of the formation of reductive coupling compounds and metal‐catalyzed formation of C60H2 are both new to metal catalysis and fullerene chemistry.
Two‐Photon Fluorescent Probes for Bioimaging (Eur. J. Org. Chem. 17/2012)
Authors: Yao Sheng , Belfield Kevin D. 
Published: May 2012

AbstractThe cover picture shows the advantage of two‐photon absorption (upper fluorescence in the cuvette), which is highly localized in three‐dimensional space, in contrast to conventional or one‐photon absorption (lower fluorescence in the cuvette), in deep tissue imaging as shown in a tumor derived from HeLa cells (upper right) with efficient two‐photon absorbing fluorescent dyes such as that pictured in the upper left. Details are presented in the Microreview by S. Yao and K. D. Belfield on p. 3199 ff. magnified image
Insights into molecular mechanisms contributing to individual susceptibility to steatohepatitis: Lessons learned from mouse models
Authors: Snider N T , Weerasinghe S V , Singla A , Leonard J M , Hanada S , Andrews P C 
Published: May 2012

Abstract

Genetic factors impact liver injury susceptibility and disease progression. Prominent histological features of some chronic human liver diseases are hepatocyte ballooning and Mallory-Denk bodies. In mice, these features are induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) in a strain-dependent manner, with the C57BL and C3H strains showing high and low susceptibility, respectively. To identify modifiers of DDC-induced liver injury, we compared C57BL and C3H mice using proteomic, biochemical, and cell biological tools. DDC elevated reactive oxygen species (ROS) and oxidative stress enzymes preferentially in C57BL livers and isolated hepatocytes. C57BL livers and hepatocytes also manifested significant down-regulation, aggregation, and nuclear translocation of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). GAPDH knockdown depleted bioenergetic and antioxidant enzymes and elevated hepatocyte ROS, whereas GAPDH overexpression decreased hepatocyte ROS. On the other hand, C3H livers had higher expression and activity of the energy-generating nucleoside-diphosphate kinase (NDPK), and knockdown of hepatocyte NDPK augmented DDC-induced ROS formation. Consistent with these findings, cirrhotic, but not normal, human livers contained GAPDH aggregates and NDPK complexes. We propose that GAPDH and NDPK are genetic modifiers of murine DDC-induced liver injury and potentially human liver disease.
ESTIMATION OF TREATMENT EFFECTS WITHOUT AN EXCLUSION RESTRICTION: WITH AN APPLICATION TO THE ANALYSIS OF THE SCHOOL BREAKFAST PROGRAM
Authors: Millimet Daniel L. , Tchernis Rusty 
Published: May 2012

SUMMARYThe increase in childhood obesity has garnered the attention of many in policymaking circles. Consequently, school nutrition programs such as the School Breakfast Program (SBP) have come under scrutiny. The identification of the causal effects of such programs, however, is difficult owing to non‐random selection into the program and the lack of exclusion restrictions. Here, we propose two new estimators aimed at addressing this situation. We compare our new estimators to existing approaches using simulated data. We show that while correlations might suggest that SBP causes childhood obesity, SBP is likely to reduce childhood obesity once selection is addressed. Copyright © 2012 John Wiley & Sons, Ltd.
Distinct functions of JNK and c‐Jun in oxidant‐induced hepatocyte death
Authors: Amir Muhammad , Liu Kun , Zhao Enpeng , Czaja Mark J. 
Published: May 2012

AbstractOveractivation of c‐Jun N‐terminal kinase (JNK)/c‐Jun signaling is a central mechanism of hepatocyte injury and death including that from oxidative stress. However, the functions of JNK and c‐Jun are still unclear, and this pathway also inhibits hepatocyte death. Previous studies of menadione‐induced oxidant stress demonstrated that toxicity resulted from sustained JNK/c‐Jun activation as death was blocked by the c‐Jun dominant negative TAM67. To further delineate the function of JNK/c‐Jun signaling in hepatocyte injury from oxidant stress, the effects of direct JNK inhibition on menadione‐induced death were examined. In contrast to the inhibitory effect of TAM67, pharmacological JNK inhibition by SP600125 sensitized the rat hepatocyte cell line RALA255‐10G to death from menadione. SP600125 similarly sensitized mouse primary hepatocytes to menadione toxicity. Death from SP600125/menadione was c‐Jun dependent as it was blocked by TAM67, but independent of c‐Jun phosphorylation. Death occurred by apoptosis and necrosis and activation of the mitochondrial death pathway. Short hairpin RNA knockdowns of total JNK or JNK2 sensitized to death from menadione, whereas a jnk1 knockdown was protective. Jnk2 null mouse primary hepatocytes were also sensitized to menadione death. JNK inhibition magnified decreases in cellular ATP content and β‐oxidation induced by menadione. This effect mediated cell death as chemical inhibition of β‐oxidation also sensitized cells to death from menadione, and supplementation with the β‐oxidation substrate oleate blocked death. Components of the JNK/c‐Jun signaling pathway have opposing functions in hepatocyte oxidant stress with JNK2 mediating resistance to cell death and c‐Jun promoting death. J. Cell. Biochem. 113: 3254–3265, 2012. © 2012 Wiley Periodicals, Inc.
IL‐1β‐mediated up‐regulation of DEC1 in human gingiva cells via the Akt pathway
Authors: Bhawal Ujjal K. , Ito Yumi , Tanimoto Keiji , Sato Fuyuki , Fujimoto Katsumi , Kawamoto Takeshi , Sasahira Tomonori , Hamada Nobushiro , Kuniyasu Hiroki , Arakawa Hirohisa , Kato Yukio , Abiko Yoshimitsu 
Published: May 2012

AbstractGrowing evidence indicates that inflammation is a contributing factor leading to cancer development. However, pathways involved in this progression are not well understood. The involvement of DEC1 in cancer prompted us to examine whether pro‐inflammatory cytokine interleukin‐1β (IL‐1β) induces the expression of DEC1 in oral inflammation. We found that IL‐1β up‐regulated DEC1 and hypoxia‐inducible factor‐1α (HIF‐1α) protein and elevated the HIF‐1α‐responsive gene vascular endothelial growth factor (VEGF) expression in human primary gingival cells. HIF‐1α and DEC1 immunoreactivity were significantly higher in the cases of gingival inflammation. We demonstrate that IL‐1β up‐regulates DEC1 and HIF‐1α protein through a classical inflammatory signaling pathway involving Akt. Our data strongly suggest that PI‐3K–Akt is an upstream participant in IL‐1β‐mediated DEC1 and HIF‐1α induction. This is supported by the following data: (1) IL‐1β induces 473 serine phosphorylation of Akt; (2) IL‐1β‐mediated Akt activation occurs in a PI‐3K‐dependent manner, and specific inhibition of PI‐3K prevents Akt phosphorylation; and (3) inhibition of Akt prevents IL‐1β‐mediated DEC1 and HIF‐1α induction. Taken together, these results suggest that DEC1 is one of the important transcription factors in inflammation. J. Cell. Biochem. 113: 3246–3253, 2012. © 2012 Wiley Periodicals, Inc.
Gender differences in adiponectin modulation of cardiac remodeling in mice deficient in endothelial nitric oxide synthase
Authors: Durand Jorge L. , Nawrocki Andrea R. , Scherer Philipp E. , Jelicks Linda A. 
Published: May 2012

AbstractLeft ventricular hypertrophy (LVH) is a risk factor for cardiovascular disease, a leading cause of death. Alterations in endothelial nitric oxide synthase (eNOS), an enzyme involved in regulating vascular tone, and in adiponectin, an adipocyte‐derived secretory factor, are associated with cardiac remodeling. Deficiency of eNOS is associated with hypertension and LVH. Adiponectin exhibits vaso‐protective, anti‐inflammatory, and anti‐atherogenic properties. We hypothesized that increased levels of adiponectin would alleviate cardiac pathology resulting from eNOS deficiency, while decreased levels of adiponectin would exacerbate the pathology. Male and female mice, deficient in eNOS, and either lacking or over‐expressing adiponectin, were fed high fat diet (HFD) or normal chow. Cardiac magnetic resonance imaging was performed to serially assess heart morphology and function up to 40 weeks of age. Thirty‐two weeks of HFD feeding led to significantly greater LV mass in male mice deficient in eNOS and either lacking or over‐expressing adiponectin. Heart function was significantly reduced when the mice were deficient in either eNOS, adiponectin or both eNOS and adiponectin; for female mice, heart function was only reduced when both eNOS and adiponectin were lacking. Thus, while over‐expression of adiponectin in the eNOS deficient HFD fed male mice preserved function at the expense of significantly increased LV mass, female mice were protected from decreased function and increased LVH by over‐expression of adiponectin. Our results demonstrate a sexual dimorphism in response of the heart to alterations in eNOS and adiponectin during high fat feeding and suggest that adiponectin might require eNOS for some of its metabolic effects. J. Cell. Biochem. 113: 3276–3287, 2012. © 2012 Wiley Periodicals, Inc.
Interaction of IFNλR1 with TRAF6 regulates NF‐κB activation and IFNλR1 stability
Authors: Xie Yun‐Fei , Cui Ying‐Bin , Hui Xi‐Wu , Wang Lan , Ma Xiao‐Li , Chen Hong , Wang Xin , Huang Bing‐Ren 
Published: May 2012

AbstractIFNλR1 is a member of the class II cytokine receptor family, and it associates with IL‐10R2 to form a functional receptor complex, IFNλR. This receptor complex transduces signals from IFNλs (IFNλ1, IFNλ2, and IFNλ3), promoting antiviral and antiproliferative activities similar to those of type I IFNs. In an effort to further understand signal transduction through IFNλR1, we used bioinformatics analysis and identified a tumor necrosis factor receptor‐associated factor 6 (TRAF6)‐binding motif in the intracellular domain of IFNλR1. In subsequent immunoprecipitation and GST pull‐down assays, IFNλR1 was shown to immunoprecipitate with TRAF6 and was pulled down by GST‐TRAF6. Endogenous IFNλR1 and TRAF‐6 interaction implies that these proteins really interact in the cells. This interaction was abrogated upon mutation of the TRAF6‐binding motif in IFNλR1. Furthermore, the interaction between IFNλR1 and TRAF6 inhibited TRAF6‐induced NF‐κB activation, likely due to a reduction in TRAF6 autoubiquitination. Moreover, co‐expression of IFNλR1 with TRAF6 significantly increased the stability of IFNλR1, thereby prolonging its half‐life and enhancing its steady‐state level in cultured cells. J. Cell. Biochem. 113: 3371–3379, 2012. © 2012 Wiley Periodicals, Inc.
Electrocatalytic Oxidation of Paracetamol on Ni and NiCu Alloy Modified Glassy Carbon Electrode
Authors: Feizbakhsh Alireza , Aghassi Ali , Ehsani Ali , Jamaat Malihe A. , Naeemy Ali , Danaee Iman 
Published: May 2012

AbstractIn this study we investigated the electrocatalytic oxidation of anti‐inflammatory drug (paracetamol) on Nickel and Nickel–copper alloy modified glassy carbon electrodes (GC/Ni and GC/NiCu) in alkaline solution. These electrodes prepared by galvanostatic method and different electrochemical techniques such as cyclic voltammetry and chronoamperometry were used to track the oxidation process and its kinetics. From Voltammetric studies we concluded that in the presence of drugs the anodic peak current of low valences Nickel species increased, followed by a decrease in the corresponding cathodic current peak. This indicates that drugs were oxidized on the redox mediator which was immobilized on the electrode surface via an electrocatalytic mechanism. Using Laviron's equation, the values of α and ks for the immobilized redox species were determined. The anodic peak currents show linear dependency with the square root of scan rate. This behavior is the characteristic of a diffusion controlled process. Under the CA regime the reaction followed a Cottrellian behavior and the diffusion coefficient of paracetamol was found in agreement with the values obtained from CV measurements.
A Simple, Mild and Efficient One‐Pot Synthesis of 2‐Substituted Benzimidazoles in the Presence of H2O2/HCl under Microwave Irradiation
Authors: Naeimi Hossein , Alishahi Nasrin 
Published: May 2012

AbstractA simple, fast and efficient method for the preparation of several 2‐substituted benzimidazole derivatives is reported. Compounds were synthesized through a rapid one‐pot synthesis via microwave irradiation, starting from aldehydes and o‐phenylenediamine, in the presence of H2O2/HCl system in acetonitrile. The significant features of this method are short reaction times, high yields, easy and quick isolation of the products.