bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interleukin‐1‐Mediated phospholipid breakdown and arachidonic acid release in human synovial cells
Authors: Angel Juana , Colard Odile , Chevy Françoise , Fournier Catherine 
Published: May 2012

AbstractObjective. Interleukin‐1 (IL‐1), an important mediator contributing to joint destruction in rheumatoid arthritis, is known to stimulate the release of arachidonic acid (AA) and prostaglandin E2 (PGE2) from adherent synoviocytes. To study the intracellular pathways involved in these functions, we stimulated cultures of human synovial cells with recombinant IL‐1β.Methods. AA liberation was measured after labeling synovial cells with 3H‐AA, and PGE2 levels were determined by high performance liquid chromatography or radioimmunoassay. Identification of 3H‐AA‐labeled phospholipids was performed by thin layer chromatography. Cell‐associated phospholipase A2 (PLA2) enzymatic activity was determined by an assay with cell‐free systems and exogenous substrates.Results. Stimulation of synovial cells with recombinant IL‐1β induced a decrease in phosphatidylcholine (PC), phosphatidylinositol (PI), and phosphatidylethanolamine (PE), and a marked increase in cell‐associated PLA2 activity as compared with controls. In the presence of either quinacrine, an inhibitor of PLA2 pathway activation, or neomycin, which binds to PI mono‐ and biphosphate thus blocking their degradation by phospholipases, AA and PGE2 secretion were reduced in a dose‐dependent manner. Kinetic studies revealed that quinacrine had little blocking activity on the IL‐1‐mediated AA release after 1 hour of stimulation but completely abolished it after 5 or 8 hours. In contrast, neomycin exerted a partial but significant inhibitory effect from the first hour of stimulation onward. Addition of quinacrine was also demonstrated to abolish the IL‐1‐induced hydrolysis of PC and PE but not PI, indicating that PC and PE are the preferred substrates for PLA2 enzymatic activity in human synovial cells.Conclusion. Our findings strongly suggest that AA and PGE2 production by IL‐1‐triggered synoviocytes are largely dependent upon PLA2‐mediated hydrolysis of PC and PE and to a lesser extent upon the earlier degradation of PI.
Temporal covariation of soluble interleukin‐2 receptor levels, daily stress, and disease activity in rheumatoid arthritis
Authors: Harrington Laura , Affleck Glenn , Urrows Susan , Tennen Howard , Higgins Pamela , Zautra Alex , Hoffman Steven 
Published: May 2012

AbstractObjective. To examine synchronous changes in soluble interleukin‐2 receptor (sIL‐2R) levels, daily indicators of emotional stress, joint inflammation, and reported pain in patients with rheumatoid arthritis (RA).Methods. Fourteen patients were studied on each of 6 occasions, 2 weeks apart. Measures included daily ratings of mood disturbance, undesirable events, and joint pain; clinical examination of joint swelling; and serum assays of sIL‐2R. Pooled within‐person correlations among these variables were calculated.Results. Consistent with the results of previous research, joint inflammation covaried directly with sIL‐2R levels. Changes in mood disturbance were unrelated to changes in joint inflammation, but increases in mood disturbance were linked with decreases in sIL‐2R levels and increases in reported joint pain.Conclusion. These findings provide preliminary evidence that psychoimmune processes may be implicated in short‐term changes in RA disease activity.
Complete heart block and seizures in an adult with systemic lupus erythematosus: A possible pathophysiologic role for anti‐SS‐A/Ro and anti‐SS‐B/La autoantibodies
Authors: Mevorach Dror , Raz Eyal , Shalev Oded , Steiner Israel , Ben‐Chetrit Eldad 
Published: May 2012

AbstractObjective. To determine the serum autoantibody profile in an adult patient with systemic lupus erythematosus manifested by complete heart block (CHB) and seizures, and to investigate the source of autoantibodies found in the patient's cerebrospinal fluid (CSF).Methods. The serum and CSF autoantibody profiles were determined by serologic testing and Western blot studies. An antibody activity index was devised to determine the source of the autoantibodies found in the CSF.Results. The patient's serum contained anti‐SS‐A (52 kd and 60 kd), anti‐SS‐B, anti‐U1 RNP, and anti‐Sm autoantibodies. Studies of her CSF, however, revealed only anti‐SS‐A and anti‐SS‐B autoantibodies, with a high antibody activity index.Conclusion. The finding of anti‐SS‐A (52 kd and 60 kd) and anti‐SS‐B autoantibodies was similar to reported findings in congenital CHB. Intrathecal synthesis of anti‐SS‐A and anti‐SS‐B was the source of autoantibodies found in the CSF. This patient's symptoms may be pathophysiologically linked to an immune reaction between the anti‐SS‐A and anti‐SS‐B autoantibodies and neural tissue in the brain and heart.
Ira M. Goldstein, MD, 1942–1992
Authors: Holmes Oliver Wendell 
Published: May 2012

Abstract“Those who do not know the torment of the unknown cannot have the joy of discovery which is certainly the liveliest that the mind of man can ever feel. But by a whim of our nature, the joy of discovery, so sought and hoped for, vanishes as soon as found. … This is the feeling that made Priestley say that each discovery we make shows us many others that should be made; this is the feeling which Pascal expressed, when he said: We are in search never of things, but of the search for things.”
Multiple juvenile idiopathic arthritis subtypes demonstrate proinflammatory IgG glycosylation
Authors: Ercan Altan , Barnes Michael G. , Hazen Melissa , Tory Heather , Henderson Lauren , Dedeoglu Fatma , Fuhlbrigge Robert C. , Grom Alexei , Holm Ingrid A. , Kellogg Mark , Kim Susan , Adamczyk Barbara , Rudd Pauline M. , Son Mary Beth , Sundel Robert P. , Foell Dirk , Glass David N. , Thompson Susan D. , Nigrovic Peter A. 
Published: May 2012

AbstractObjectiveRheumatoid arthritis is associated with an excess of agalactosylated (G0) IgG that is considered relatively proinflammatory. Assessment of this association in juvenile idiopathic arthritis (JIA) is complicated by age‐dependent IgG glycan variation. The aim of this study was to conduct the first large‐scale survey of IgG glycans in healthy children and patients with JIA, with a focus on early childhood, the time of peak JIA incidence.MethodsIgG glycans from healthy children and disease‐modifying antirheumatic drug–naive patients with JIA were characterized using high‐performance liquid chromatography. Agalactosylated glycans were quantitated with reference to monogalactosylated (G1) species. Associations were sought between the G0:G1 ratio and disease characteristics.ResultsAmong healthy children ages 9 months to 16 years (n = 165), the G0:G1 ratio was highly age dependent, with the ratio peaking to 1.19 in children younger than age 3 years and declining to a nadir of 0.83 after age 10 years (Spearman's ρ = 0.60, P < 0.0001). In patients with JIA (n = 141), the G0:G1 ratio was elevated compared with that in control subjects (1.32 versus 1.02; P < 0.0001). The G0:G1 ratio corrected for age was abnormally high in all JIA subtypes (enthesitis‐related arthritis was not assessed), most strikingly in systemic JIA. Glycosylation aberrancy was comparable in patients with and those without antinuclear antibodies and in both early‐ and late‐onset disease and exhibited at most a weak correlation with markers of inflammation.ConclusionIgG glycosylation is skewed toward proinflammatory G0 variants in healthy children, in particular during the first few years of life. This deviation is exaggerated in patients with JIA. The role for IgG glycan variation in immune function in children, including the predilection of JIA for early childhood, remains to be defined.
Spontaneous Formation of Giant Polymer Vesicles through a Nucleation and Growth Pathway
Authors: Qian Hanqing , Yao Wei , Yu Shuling , Chen Ying , Wu Wei , Jiang Xiqun 
Published: May 2012

AbstractThe non‐membrane‐closing formation of polymer vesicles was demonstrated by the self‐assembly of an amphiphilic hydrogen‐bonded interpolymer complex of HPC and PAA. A dynamic‐formation process that involved a nucleation and growth pathway was observed experimentally that was different from the theoretical predictions of both the membrane‐closing model and the nucleation and growth model. A series of intermediate states between the solid spheres and vesicles were visually captured by the addition of an inorganic salt followed by dilution.
Beurteilung der Wirksamkeit von Fasern zur Reduzierung von Schrumpfrissen in Beton
Authors: Fontana Patrick , Pirskawetz Stephan 
Published: May 2012

AbstractEs ist bekannt, dass eine Faserbewehrung die Schrumpfrissbildung in Beton vermindern kann. In der Literatur finden sich jedoch zum Teil widersprüchliche Angaben über die Wirksamkeit unterschiedlicher Faserarten, und deren Wirkungsmechanismus ist noch nicht vollständig geklärt. Fasern, die in Deutschland als Betonzusatzstoff eingesetzt werden sollen, bedürfen einer Zulassung durch das DIBt, das für den Nachweis ihrer Wirksamkeit zur Verminderung der Schrumpfrissbildung ein Prüfverfahren mit großformatigen Platten vorschreibt. In diesem Bericht werden die Ergebnisse einer Studie vorgestellt, in der die Eignung verschiedener Prüfverfahren hinsichtlich der Beurteilung der Wirksamkeit von Polymerfasern untersucht wurde. Dieser Bericht ist eine verkürzte Fassung eines Beitrags zum 52. Forschungskolloquium des DAfStb.
Human collagen isolated from adipose tissue
Authors: Kim Beob Soo , Choi Ji Suk , Kim Jae Dong , Yoon Hwa In , Choi Young Chan , Cho Yong Woo 
Published: May 2012

AbstractCollagen, the most abundant protein in vertebrates, is a useful biomaterial in pharmaceutical and medical industries. So far, most collagen has been extracted from animals and cadavers. Herein, we suggest human adipose tissue, which is routinely abandoned after liposuction, as a plentiful source of human collagen. In this study, human collagen was obtained from adipose tissue through two successive major steps: (i) extraction of the extracellular matrix (ECM) by pulverization, centrifugation, alkaline, and alcohol treatment; (ii) isolation of collagen from ECM by pepsin treatment in dilute acetic acid. The purified human adipose‐derived collagen was characterized by Fourier transform infrared spectroscopy, polyacrylamide gel electrophoresis, amino acid analysis, and circular dichroism spectroscopy. The extracted collagen showed a typical triple helix structure, good thermal stability due to abundant imino acids, and high solubility at acidic pH. The collagen greatly facilitated the adhesion and proliferation of human adipose‐derived stem cells and normal human dermal fibroblasts on polystyrene plates. These results suggest that human adipose tissue obtained by liposuction can provide human collagen for use in cosmetics, pharmaceutics, and medicine. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 973–980, 2012
Malachite Green Derivatives for Two‐Photon RNA Detection
Authors: Lux Jacques , Peña Eduardo José , Bolze Frédéric , Heinlein Manfred , Nicoud Jean‐François 
Published: May 2012

AbstractThe design, preparation and characterisation of a library of malachite green (MG) derivatives for two‐photon RNA labelling is described. Some of these MG derivatives exhibit an increased affinity for an MG‐aptamer, as well as improved two‐photon sensitivity when compared to the classical malachite green chloride. The underlying mechanisms and potential benefits for in vivo RNA visualisation are discussed.
Efficient DNA Strand Displacement by a W‐Shaped Nucleoside Analogue (WNA‐βT) Containing an ortho‐Methyl‐Substituted Phenyl Ring
Authors: Aoki Eriko , Taniguchi Yosuke , Wada Yasumasa , Sasaki Shigeki 
Published: May 2012

AbstractMolecules that can target duplex DNA with sequence selectivity have the potential to be useful tools in genomic research and also as therapeutic agents. Homopurine–homopyrimidine stretches in duplex DNA can be recognized by homopurine or homopyrimidine TFOs (triplex‐forming oligonucleotides) through the formation of triplex DNA. We have previously developed bicyclic nucleoside analogues (WNAs) for the formation of stable triplexes in the formation of stable antiparallel triplexes containing a TA or a CG interrupting site. In this study, we investigated the effects on triplex DNA formation of ortho‐, meta‐, and para‐methyl substituent groups on the aromatic ring of the WNA analogue. It was found that the homopurine TFO containing meta‐ and para‐methyl‐substituted WNA‐βT (mMe‐WNA‐βT, pMe‐WNA‐βT) stabilized triplexes containing a TA interrupting site or a GC site, respectively. Interestingly, the ortho‐methyl‐substituted WNA‐βT (oMe‐WNA‐βT) efficiently promoted DNA strand displacement to form the TFO/pyrimidine duplex. A detailed investigation showed that the duplex was in the antiparallel orientation and that its formation took place prior to triplex formation with the need for a magnesium cation. NOESY measurements indicated a significant difference in the rotation flexibilities of the phenyl rings of WNA‐βTs: that is, the conformation of the ortho‐methylated phenyl ring was stable in a temperature‐independent manner. It was speculated that the initial formation of a ternary complex was followed by strand displacement and then the formation of the TFO/pyrimidine duplex together with the TFO2/pyrimidine triplex formation during the early stage, and that the equilibrium shifted to the triplex during the later stage. Although the detailed role is still uncertain, the fixed phenyl ring of oMe‐WNA‐βT might play a role in the displacement reaction.
Percutaneous atrial Septal Occluder devices and cardiac erosion: A review of the literature
Authors: Crawford Geoffrey B. , Brindis Ralph G. , Krucoff Mitchell W. , Mansalis Benjamin P. , Carroll John D. 
Published: May 2012

AbstractObjectiveTo systematically review all cases in the literature of erosion associated with Atrial Septal Defect (ASD) occluder devices.BackgroundDelayed erosion of the aortic or atrial wall is an infrequent but potentially lethal complication of percutaneous septal defect closure using an ASD device. The epidemiology is poorly understood.MethodsThe MEDLINE database was searched for cases of ASD occluder device‐associated erosion.ResultsTwenty‐five articles present erosion events associated with the AMPLATZER™ Septal Occluder (ASO) device (March 2002–June 2011), documenting 21 independent, surgically confirmed cases. Another 79 distinct events are reported in case series and review articles. Of all identified independent cases, 73 were reported in the United States. No articles associate the HELEX™ Septal occluder and erosions. Additional events are reported in association with FDA‐unapproved percutaneous defect closure devices (n = 16). Estimation of ASO erosion incidence is unreliable because the numerator (number of erosion events) and denominator (number of patients with an implanted device) are unknown; estimates range from 0.1 to 0.3%.ConclusionCardiac erosion is a rare but serious complication of the ASO device. Erosion events are most often ascribed to device over‐sizing or deficient retro‐aortic rims; however, both consensus and evidence for a cogent risk factor(s) is lacking. Further assessment of the root cause of erosion and true incidence of this complication is required; analyses using control patients and/or device registry establishment represent logical next steps. © 2012 Wiley Periodicals, Inc.
Design of a Plate‐Type Catalytic Microreactor with CO2 Permeation Membrane for Water‐Gas Shift Reaction
Authors: Fukuda T. , Maki T. , Mae K. 
Published: May 2012

AbstractA method for designing membrane reactors with microchannels is discussed. The design equations were simplified under various assumptions, and a simple model that only incorporates the material balance equations was developed. The activity of the catalyst and the membrane capacity are important properties of a membrane reactor. In the proposed design method, these two parameters are combined into the nondimensional number κ. The simple model was applied to the water‐gas shift reaction and the results were compared with those obtained from the detailed model by computational fluid dynamics calculations. Moreover, a reactor was designed that could achieve a CO concentration of 10 ppm or less. In this plate‐type reactor, the temperature distribution in the channel can be controlled by adjusting the wall temperatures.
Chromatographic Reactors
Authors: Rodrigues A. E. , Pereira C. S. M. , Santos J. C. 
Published: May 2012

AbstractChromatographic reactors combining reaction and separation processes in a single unit of equipment are a way of achieving process intensification, which can lead to better energy efficiency, productivity improvement, and lower solvent consumption. In this review, two technologies for the implementation of chromatographic reactors, the simulated moving‐bed reactor and the pressure swing adsorptive reactor will be discussed with examples from liquid phase processes: green fuels (acetals) and solvents (ethyl lactate), petrochemicals (isomerization/separation of xylenes) and sugars (inversion of sucrose, glucose isomerization); and gas phase processes: hydrogen production from steam methane reforming with carbon dioxide capture.
Metal–Ligand Cooperation in Catalytic Intramolecular Hydroamination: A Computational Study of Iridium–Pyrazolato Cooperative Activation of Aminoalkenes
Authors: Tobisch Sven 
Published: May 2012

AbstractThe present study comprehensively explores diverse mechanistic pathways for intramolecular hydroamination of prototype 2,2‐dimethyl‐4‐penten‐1‐amine by Cp*Ir chloropyrazole (1; Cp*=pentamethylcyclopentadienyl) in the presence of KOtBu base with the aid of density functional theory (DFT) calculations. The most accessible mechanistic pathway for catalytic turnover commences from Cp*Ir pyrazolato (Pz) substrate adduct 2⋅S, representing the catalytically competent compound and proceeds via initial electrophilic activation of the olefin CC bond by the metal centre. It entails 1) facile and reversible anti nucleophilic amine attack on the iridium–olefin linkage; 2) IrC bond protonolysis via stepwise transfer of the ammonium NH proton at the zwitterionic [Cp*IrPz–alkyl] intermediate onto the metal that is linked to turnover‐limiting, reductive, cycloamine elimination commencing from a high‐energy, metastable [Cp*IrPz–hydrido–alkyl] species; and 3) subsequent facile cycloamine liberation to regenerate the active catalyst species. The amine–iridium bound 2 a⋅S likely corresponds to the catalyst resting state and the catalytic reaction is expected to proceed with a significant primary kinetic isotope. This study unveils the vital role of a supportive hydrogen‐bonded network involving suitably aligned β‐basic pyrazolato and cycloamido moieties together with an external amine molecule in facilitating metal protonation and reductive elimination. Cooperative hydrogen bonding thus appears pivotal for effective catalysis. The mechanistic scenario is consonant with catalyst performance data and furthermore accounts for the variation in performance for [Cp*IrPz] compounds featuring a β‐ or γ‐basic pyrazolato unit. As far as the route that involves amine NH bond activation is concerned, a thus far undocumented pathway for concerted amidoalkene → cycloamine conversion through olefin protonation by the pyrazole NH concurrent with NC ring closure is disclosed as a favourable scenario. Although not practicable in the present system, this pathway describes a novel mechanistic variant in late transition metal–ligand bifunctional hydroamination catalysis that can perhaps be viable for tailored catalyst designs. The insights revealed herein concerning the operative mechanism and the structure–reactivity relationships will likely govern the rational design of late transition metal–ligand bifunctional catalysts and facilitate further conceptual advances in the area.
Localization/Delocalization of Charges in Bay‐Linked Perylene Bisimides
Authors: Jiang Wei , Xiao Chengyi , Hao Linxiao , Wang Zhaohui , Ceymann Harald , Lambert Christoph , Di Motta Simone , Negri Fabrizia 
Published: May 2012

AbstractThe copper‐mediated Ullmann coupling of 1,7‐dibromoperylene bisimides afforded structurally perfect singly‐linked perylene bisimide (PBI) arrays, whilst the homo‐coupling of 1,12‐dibromoperylene bisimides gave doubly‐linked and triply‐linked diperylene bisimides. The interactions of three bay‐linked diperylene bisimides that differed in their linkage (singly, doubly, and triply) were investigated in their neutral and reduced forms (mono‐anion to tetra‐anion). UV/Vis absorption and fluorescence spectroscopy revealed different degrees of interaction, which was explained by exciton coupling and conjugation effects. The electrochemical properties and spectroelectrochemistry also showed quite‐different degrees of PBI interactions in the reduced mixed‐valence species, which was apparent by the observation of CT bands. The interpretation of the experimental findings was supported by spin‐restricted and ‐unrestricted DFT and time‐dependent TD‐DFT calculations with the long‐range‐corrected CAM‐B3LYP functional. Accordingly, the degree of interaction in both the neutral and reduced forms of the bay‐linked PBIs was qualitatively in the order doubly linked<singly linked≪triply linked, owing to the different degrees of twisting and flexibility between the two PBIs moieties. Only triply linked diPBI showed completely delocalized wavefunctions over the entire π‐system.
Chiral J‐Aggregates of Atropo‐Enantiomeric Perylene Bisimides and Their Self‐Sorting Behavior
Authors: Xie Zengqi , Stepanenko Vladimir , Radacki Krzysztof , Würthner Frank 
Published: May 2012

AbstractHerein we report on structural, morphological, and optical properties of homochiral and heterochiral J‐aggregates that were created by nucleation–elongation assembly of atropo‐enantiomerically pure and racemic perylene bisimides (PBIs), respectively. Our detailed studies with conformationally stable biphenoxy‐bridged chiral PBIs by UV/Vis absorption, circular dichroism (CD) spectroscopy, and atomic force microscopy (AFM) revealed structurally as well as spectroscopically quite different kinds of J‐aggregates for enantiomerically pure and racemic PBIs. AFM investigations showed that enantiopure PBIs form helical nanowires of unique diameter and large length‐to‐width ratio by self‐recognition, while racemic PBIs provide irregular‐sized particles by self‐discrimination of the enantiomers at the stage of nucleation. Steady‐state fluorescence spectroscopy studies revealed that the photoluminescence efficiency of homochiral J‐aggregated nanowires (47±3 %) is significantly higher than that of heterochiral J‐aggregated particle‐like aggregates (12±3 %), which is explained in terms of highly ordered molecular stacking in one‐dimensional nanowires of homochiral J‐aggregates. Our present results demonstrate the high impact of homochirality on the construction of well‐defined nanostructures with unique optical properties.
ChemInform Abstract: Mixed MetalII—MetalIV Hybrid Fluorides.
Authors: Lhoste Jerome , Adil Karim , Le Bail Armel , Leblanc Marc , Hemon‐Ribaud Annie , Maisonneuve Vincent 
Published: May 2012

AbstractThe new compounds [Ni(en)3]·(TiF6) (I), [PyH]2[Cu(Py)4(TiF6)2] (II), [PyH]2[Cu(Py)4(MoF6)2] (III), [H3O]2 [SiF6(CuF(Py)4)2]·(F)2 (IV), Cu(en)2TiF6 (V), and Cu(en)2SiF6 (VI) are solvothermally synthesized from mixtures of TiO2, MoO2, SiO2, CuO or NiO, HF solution, Py, en, and EtOH (microwave heating, 160 °C, autoclave, 1 h).
ChemInform Abstract: Closely Related Rare‐Earth Metal Germanides RE2Li2Ge3 and RE3Li4Ge4 (RE: La—Nd, Sm): Synthesis, Crystal Chemistry, and Magnetic Properties.
Authors: Guo Sheng‐Ping , You Tae‐Soo , Bobev Svilen 
Published: May 2012

AbstractThe title compounds are synthesized from stoichiometric mixtures of the elements (Nb tubes, 1253—1358 K, 5 h) and characterized by single crystal XRD, magnetic measurements, and TB‐LMTO computations.