bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of antigen‐expressing dendritic cells by double negative regulatory T cells
Authors: Gao Julia Fang , McIntyre Megan S. Ford , Juvet Stephen C. , Diao Jun , Li Xujian , Vanama Ramesh B. , Mak Tak W. , Cattral Mark S. , Zhang Li
Published: June 2011

TCRαβ+CD3+CD4−CD8−NK1.1− double negative (DN) Tregs comprise 1–3% of peripheral T lymphocytes in mice and humans. It has been demonstrated that DN Tregs can suppress allo‐, xeno‐ and auto‐immune responses in an Ag‐specific fashion. However, the mechanisms by which DN Tregs regulate immune responses remain elusive. Whether DN Tregs can regulate DCs has not been investigated previously. In this study, we demonstrate that DN Tregs express a high level of CTLA4 and are able to down‐regulate costimulatory molecules CD80 and CD86 expressed on Ag‐expressing mature DCs (mDCs). DN Tregs from CTLA4 KO mice were not able to downregulate CD80 and CD86 expression, indicating that CTLA4 is critical for DN Treg‐mediated downregulation of costimulatory molecule expression on Ag‐expressing mature DCs. Furthermore, DN Tregs could kill both immature and mature allogeneic DCs, as well as Ag‐loaded syngeneic DCs, in an Ag‐specific manner in vitro and in vivo, mainly through the Fas‐FasL pathway. These data demonstrate, for the first time, that DN Tregs are potent regulators of DCs and may have the potential to be developed as a novel immune suppression treatment.
Enhancing alloreactivity does not restore GVHD induction but augments skin graft rejection by CD4+ effector memory T cells
Authors: Anderson Britt E. , Tang Anita L. , Wang Ying , Froicu Monica , Rothstein David , McNiff Jennifer M. , Jain Dhanpat , Demetris Anthony J. , Farber Donna L. , Shlomchik Warren D. , Shlomchik Mark J.
Published: June 2011

Graft‐versus‐host disease (GVHD) caused by donor T cells attacking recipient tissues is a major cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation (alloSCT). Studies have shown that effector memory T (TEM) cells do not cause GVHD but are capable of immune functions post‐transplant, including graft‐versus‐leukemia (GVL) effects, but the reasons for this are unclear. In mice, the TEM pool may have a less diverse T‐cell receptor (TCR) repertoire than naive T (TN) cells with fewer alloreactive clones. We therefore tested whether enhancing the alloreactivity of TEM cells would restore their ability to cause GVHD. In an MHC‐matched system, alloreactive TEM cells were created by transferring GVHD effector cells into syngeneic recipients and allowing conversion to TEM cells. Upon retransfer to freshly transplanted recipients, these cells caused only mild GVHD. Similarly, in an MHC‐mismatched system, TEM cells with a proven increased precursor frequency of alloreactive clones only caused limited GVHD. Nonetheless, these same cells mounted strong in vitro alloresponses and caused rapid skin graft rejection. TEM cells created from CD4+ T cells that had undergone lymphopenia‐induced proliferation (LIP) also caused only mild GVHD. Our findings establish that conversion to TEM cells significantly reduces GVHD potency, even in cells with a substantially enhanced alloreactive repertoire.
Group 11 Amidinates and Guanidinates: Potential Precursors for Vapour Deposition
Authors: Whitehorne Todd J. J. , Coyle Jason P. , Mahmood Ahsan , Monillas Wesley H. , Yap Glenn P. A. , Barry Seán T.
Published: June 2011

Several guanidinates of copper and silver, as well as amidinates and guanidinates of gold were synthesized as potential precursors for vapour deposition methods. These compounds were found to be dimers in the case of copper and gold, and trimers in the case of silver. The copper compounds showed good thermal and photostability, and were isolable by sublimation. The silver compounds proved to be very reactive to both heat and light, and were found to deposit silver metal when heated, suggesting that these sensitive compounds might be used as single source precursors. The gold compounds were found to exhibit some heat and light sensitivity, but were much more stable than their silver counterparts. Specifically, [Au(NiPr)2NMe2]2 (8) was found to be sublimable at 85 °C and 20 mTorr, and deposited gold metal under higher temperatures. These metal‐depositing thermal reactions were thought to abstract a hydrogen from the guanidinate ligand, which acts as the reducing agent. Interestingly, the gold amidinate compounds were found to produce diisopropylcarbodiimide when heated, suggesting that these compounds deinsert carbodiimide rather than abstract a hydrogen atom from the ligand.
Bioavailability and pharmacokinetics of bufadienolides‐loaded lipid microspheres after different administrations to rats
Authors: Weng Yan , Jin Jian , Pan Cheng , Meng Lingkuo , Tang Xing
Published: June 2011

The degradation kinetics in vitro and pharmacokinetics of bufadienolides loaded in lipid microsphere (BU‐LM) after intravenous (IV) administration were investigated and compared with bufadienolides solution (BU‐S). The bioavailabilities of BU‐LM after intraportal (FIP), intraduodenal (FID), and intragastric (FIG) administrations to rats were also evaluated. The degradation kinetics showed that BU‐LM could protect bufadienolides from rapid metabolism in the plasma and gastrointestinal tract. The pharmacokinetic study revealed that BU‐LM after IV administration exhibited longer half‐life, longer mean residence time and higher apparent volume of distribution than intravenous BU‐S. After different routes of administration of BU‐LM, cinobufagin (C), and resibufogenin (R) were metabolized completely and could not be detected at an oral dose of 6 mg/kg. Furthermore, C exhibited a complete hepatic first‐pass effect after IP administration of 0.5 mg/kg BU‐LM. Bufalin (B), the lowest component of the BU‐LM could be detected at any administration and the FIG, FID, and FIP for B were 43.05, 88.93, and 93.31%, respectively. R had a FID and FIP of only 1.51 and 2.77%, respectively. The results demonstrated that the stomach appeared to be the dominating site of metabolism for B and the liver for C and R.

Practical applications: Bufadienolides, consisting of bufalin (B), binobufagin (C), and resibufogenin (R) are easily hydrolyzed (catalyzed by acids, bases, and enzymes) and are metabolized rapidly in rats because of their chemical structures, especially C. However, the three bufadienolides could be protected from degradation effectively and the degradation half‐lives could be extended to different degrees by using lipid microspheres (LM) as a delivery system. Also, after intravenous administration to rats, bufadienolides‐loaded lipid microspheres (BU‐LM) could slow down the metabolism and elimination of bufadienolides, delay the release and increase the targeted effect of the drug compared with bufadienolides aqueous solution (BU‐Siv). Consequently, LM is a promising alternative vehicle for bufadienolides.
Anodic Stripping Voltammetry Combined with Sequential Injection Analysis for Measurements of Trace Metal Ions with Bismuth‐ and Antimony Film Electrodes under Comparable Conditions
Authors: Guzsvány Valéria , Nakajima Hizuru , Soh Nobuaki , Nakano Koji , Švancara Ivan , Vytřas Karel , Bjelica Luka , Imato Toshihiko
Published: June 2011

Anodic stripping voltammetry combined with sequential injection analysis (ASV‐SIA) was selected to examine the use of bismuth‐ and antimony‐film plated glassy carbon electrodes under comparable conditions for the determination of Pb(II) and Cd(II) ions. Of interest were the conditions for film deposition, as well as the composition of sample/carrier solutions, including concentrations of Sb(III) or Bi(III) and HCl. Then, by the optimized procedure, one could determine Pb(II), Cd(II), and Zn(II) ions at the low µg L−1 level and ASV‐SIA configuration with both electrodes tested on analysis of a water sample.
Biocidal and anti‐corrosive activities of benzoimidazol‐3‐ium cationic Schiff base surfactants
Authors: Negm Nabel A. , Ghuiba Ferial M. , Mahmoud Soad A. , Tawfik Salah M.
Published: June 2011

Two series of cationic Schiff base surfactants, namely, 2‐(benzylideneamino)‐3‐(2‐oxo‐2‐alkoxyethyl)‐1,3‐benzoimidazol‐3‐ium bromide (IA–D) and 2‐[(4‐methoxybenzylidene) amino]‐3‐(2‐oxo‐2‐alkoxyethyl)‐1,3‐benzoimidazol‐3‐ium bromide (IIA–D) were prepared. The chemical structures of the prepared Schiff bases were recognized by elemental analysis, FTIR, H NMR, C13‐NMR and GC/MS spectra. The surface activities of the synthesized Schiff base cationic surfactants showed their tendency towards adsorption at the air/water interface. The adsorption tendency was estimated from the values of surface tension and the depression of surface tension at the critical micelle concentration. The studied surfactants were evaluated as antimicrobial agents against pathogenic and sulfur‐reducing bacteria using inhibition zone diameters and minimum inhibition concentration values. The synthesized cationic benzoimidazolium Schiff base cationic surfactants showed good antimicrobial activities against the tested microorganisms including Gram positive, Gram negative as well as fungi. The synthesized compounds were tested for the activity as corrosion inhibitors against carbon steel corrosion in 0.5 M HCl at 200 and 400 ppm. The promising inhibition efficiency of these compounds against the sulfur‐reducing bacteria facilitates them to be applicable in the petroleum field as new categories of Sulfur Reducing Bacteria biocides. The inhibition efficiencies of the tested compounds showed good inhibition and protection of the carbon steel. The corrosion inhibition tendency correlated to the surface activity and chemical structure of the compounds.
External sensors in partial discharge ultra‐high‐frequency measurements in gas‐insulated substations
Authors: Tang Ju , Wei Gang , Zhang Xiaoxing
Published: June 2011

Although the ultra‐high‐frequency (UHF) method of detecting partial discharge (PD) in gas insulation substations (GISs) is an interesting research topic because of its remarkable anti‐jamming ability, applying inner UHF sensors to detect PD in operational GISs is a difficult task. The structure of GISs and the characteristics of PD electromagnetic wave transmission and leakage are determined using external antenna sensors to detect PD signals based on the theory of linear antennas. Two decimetric‐wave antennas with different detection bandwidths are made using techniques such as additional impedance, shielding and asymmetrical forms to measure UHF. The UHF external antenna sensor measurement system is able to collect PD signals from the GIS equipment, and its anti‐jamming ability is better than that of the low‐frequency sensor measurement system in the UHF band. Copyright © 2011 John Wiley & Sons, Ltd.
A new method for arcing fault location using discrete wavelet transform and wavelet networks
Authors: Jamali Sadegh , Ghaffarzadeh Navid
Published: June 2011

This paper presents a new method for arcing (transient) fault location by combining discrete wavelet transform (DWT) and wavelet networks (WNs). The single‐end relaying point voltage and current waveforms (captured with a sampling rate of 2.5 kHz) are de‐noised by DWT to obtain a higher signal‐to‐noise ratio. The feature vectors contain the magnitudes of the three phase post‐fault voltage and current fundamental frequency phasors obtained by DWT. The feature vectors for different arcing fault conditions are applied to WN for training and testing purposes. Although the prime aim of the proposed method is arcing fault location, it can also be applied for permanent faults. The accuracy of the proposed method has been tested and verified under various fault conditions on a 400 kV overhead line using the Electro‐Magnetic Transient Program (EMTP) software package. Performance of the new method has also been compared with several existing methods under similar fault conditions, and the test results show better accuracy of the proposed method. Copyright © 2011 John Wiley & Sons, Ltd.
Electromagnetic torque ripple and copper losses reduction in permanent magnet synchronous machines
Authors: Monteiro J. R. B. A. , Oliveira A. A. , Aguiar M. L. , Sanagiotti E. R.
Published: June 2011

This paper presents a method for electromagnetic torque ripple and copper losses reduction in (non‐sinusoidal or trapezoidal) surface‐mount permanent magnet synchronous machines (SM‐PMSM). The method is based on an extension of classical dq transformation that makes it possible to write a vectorial model for this kind of machine (with a non‐sinusoidal back‐EMF waveform). This model is obtained by the application of that transformation in the classical machine per‐phase model. That transformation can be applied to machines that have any type of back‐EMF waveform, and not only trapezoidal or square‐wave back‐EMF waveforms. Implementation results are shown for an electrical converter, using the proposed vectorial model, feeding a non‐sinusoidal synchronous machine (brushless DC motor). They show that the use of this vectorial mode is a way to achieve improvements in the performance of this kind of machine, considering the electromagnetic torque ripple and copper losses, if compared to a drive system that employs a classical six‐step mode as a converter. Copyright © 2011 John Wiley & Sons, Ltd.
Origin and diamond prospectivity of Mesoproterozoic kimberlites from the Narayanpet field, Eastern Dharwar Craton, southern India: insights from groundmass mineralogy, bulk‐chemistry and perovskite oxybarometry
Authors: Chalapathi Rao N. V. , Paton C. , Lehmann B.
Published: June 2011

The Mesoproterozoic Narayanpet Kimberlite Field (NKF) is located ~200 km north of the well‐known Wajrakarur Kimberlite Field (WKF) in the Eastern Dharwar Craton, southern India. Whereas a majority of the WKF occurrences are diamondiferous and contain mantle xenoliths and xenocrysts, their paucity is a characteristic feature of the NKF. This has been attributed alternately to the derivation of NKF magmas from a shallower depth, or to variability in thickness of the Sub‐Continental Lithospheric Mantle (SCLM) beneath the Eastern Dharwar Craton. Recently, exploration by De Beers resulted in the discovery of a number of new kimberlite occurrences from the NKF, with some of their geochemical features and radiogenic isotope systematics subsequently becoming available. In this paper, we present detailed petrography, groundmass mineral composition and new bulk‐rock geochemistry data for a number of NKF rocks and attempt to further constrain their origin. We also investigate the influence of redox conditions on diamond prospectivity by estimating oxygen fugacity (fO2) from Fe–Nb oxybarometry on NKF groundmass perovskites. We identify for the first time in the NKF the presence of volcaniclastic (fragmental textured) facies kimberlite belonging to the diatreme portion of the intrusion. Rarity of olivine macrocrysts and the presence of diopside are hallmarks of the NKF kimberlites, in contrast to archetypal kimberlites of southern Africa. Mineral components of the groundmass display features that are characteristic to both archetypal kimberlites and to orangeites, and it is not straight forward to apply conventional mineral‐genetic schemes in the nomenclature of the NKF pipes. Low fO2 of the NKF magma (ΔNNO (nickel–nickel oxide) = −1.9 to −3.2), indistinguishable from that of diamondiferous kimberlites world‐wide, indicates that redox conditions were favourable for diamond prospectivity, and that magmatic emplacement could, instead, have played a major role in their low diamond potential. Copyright © 2011 John Wiley & Sons, Ltd.
Epigallocatechin‐3‐gallate induced modulation of cell deadhesion and migration on thermosensitive poly(N‐isopropylacrylamide)
Authors: Li Xi , Feng Huixing , Chen Beiyi , Ng Soon Seng , Chen Wei Ning , Chan Vincent
Published: June 2011

Epigallocatechin‐3‐gallate (EGCG), which is the main polyphenolic constituent of green tea, has emerged as a promising candidate for potential applications in selected anticancer therapeutics. Generally, tumor metastasis is known to be correlated with the alterations in cell adhesion and migration of normal cells. Nevertheless, the effect of EGCG on the biophysical responses of tumor cell adhering on extracellular matrix remains obscure. In this study, a thermosenstive poly(N‐isopropylacrylamide) (PIPAAm) system was developed to elucidate the potential anti‐tumor effect of EGCG on the deadhesion and migration of HepG2 cells. First, both XPS and ELISA validated the coating of laminin (LA) on PIPAAm. Second, a change of nanotopology of LA layer on PIPAAm across the lower solution critical temperature (LCST) was detected with AFM. HepG2 cells seeded on LA‐coated PIPAAm surface was shown to go through deadhesion by lowering the temperature below the LCST. Interestingly, EGCG was shown to decelerate the thermally triggered deadhesion of HepG2 cell on LA coated PIPAAm. Moreover, the inhibition of cell deadhesion in EGCG treated cells was shown to be driven by actin remodeling. Interestingly, the modulation of cell deadhesion on LA coated PIPAAm by EGCG leads to the reduction of cell motility as shown by real‐time cell migration assay. Overall, the use of PIPAAm system demonstrated the promise of EGCG as anticancer therapy through the suppression of cell deadhesion and migration. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Rank‐width of random graphs
Authors: Lee Choongbum , Lee Joonkyung , Oum Sang‐il
Published: June 2011

Rank‐width of a graph G, denoted by rw(G), is a width parameter of graphs introduced by Oum and Seymour [J Combin Theory Ser B 96 (2006), 514–528]. We investigate the asymptotic behavior of rank‐width of a random graph G(n, p). We show that, asymptotically almost surely, (i) if p∈(0, 1) is a constant, then rw(G(n, p)) = ⌈n/3⌉−O(1), (ii) if , then rw(G(n, p)) = ⌈1/3⌉−o(n), (iii) if p = c/n and c>1, then rw(G(n, p))⩾rn for some r = r(c), and (iv) if p⩽c/n and c81, then rw(G(n, p))⩽2. As a corollary, we deduce that the tree‐width of G(n, p) is linear in n whenever p = c/n for each c>1, answering a question of Gao [2006]. © 2011 Wiley Periodicals, Inc. J Graph Theory.
Purkinje cell protein 4 positively regulates neurite outgrowth and neurotransmitter release
Authors: Harashima Shin‐ichi , Wang Yu , Horiuchi Takahiko , Seino Yutaka , Inagaki Nobuya
Published: June 2011

Purkinje cell protein 4 (PCP4), also called brain‐specific polypeptide 19 (PEP19), is a neurospecific, small calmodulin‐binding protein that binds both calcium‐free and calcium‐binding calmodulin to regulate the calmodulin‐mediated signal. The expression level of this molecule is decreased in the brain in Alzheimer's disease, Huntington's disease, and alcoholism. However, little is known of the function of PCP4 regarding neuronal or neuroendocrine cell differentiation and neurotransmitter release. To address this, we established a PCP4 tetracycline‐inducible rat chromaffin cell line, PC12. When PCP4 expression was induced with doxcycline, neurite outgrowth was significantly advanced in the presence of nerve growth factor (NGF) and dibutyryl cAMP, which was inhibited by W‐7, a calmodulin inhibitor, and PD98059, an ERK inhibitor. In addition, size of the cell body also was increased by treatment with NGF in the PCP4‐induced PC12 cells. Constitutive and potassium‐evoked release of acetylcholine and dopamine was increased and apoptosis induced by hydrogen peroxide (H2O2) was inhibited in PCP4‐induced PC12 cells. On the other hand, knockdown of PCP4 by siRNA transfection decreased neurite outgrowth and dopamine release and increased H2O2‐induced apoptosis in PC12 cells. These results indicate that PCP4 promotes neuroendocrine cell differentiation and neurotransmitter release by activating calmodulin function. © 2011 Wiley‐Liss, Inc.
Weak cation‐exchange monolithic column for capillary liquid chromatography of peptides and proteins
Authors: Chen Xin , Tolley H. Dennis , Lee Milton L.
Published: June 2011

A stable poly(2‐carboxyethyl acrylate‐co‐poly(ethylene glycol) diacrylate) monolith was synthesized inside a 75‐μm id capillary by direct in situ photo‐initiated polymerization in a binary porogenic solvent consisting of methanol and ethyl ether. The resulting monolith was evaluated for weak cation‐exchange capillary liquid chromatography of peptides and proteins. A high dynamic binding capacity of 72.7 mg lysozyme per cm3 column volume was measured. Fast mass transfer was demonstrated by steep breakthrough curves. The resulting monolith exhibited negligible hydrophobicity, leading to good separation of peptides and proteins. Peak capacities of 11 for peptides with a 10‐min salt gradient and 39 for proteins with a 20‐min salt gradient were measured. An efficiency of 37 000 plates/m for proteins was obtained under isocratic conditions. The effects of functional group concentration, porogenic solvent composition, mobile phase pH, salt gradient rate, and hydrophobicity on the retention of analytes were investigated. Good run‐to‐run relative standard deviation (RSD) <1.93% and column‐to‐column RSD <4.63% were achieved.
Solvent hydrogen bonding and structural effects on the reaction of 2‐halo‐5‐nitropyridines with parasubstituted anilines in dimethylsulfoxide/acetonitrile mixtures
Authors: Kalaimani N. , Rathinam S. , Bhuvaneshwari D. S.
Published: June 2011

Substitution reactions of some parasubstituted anilines with 2‐chloro‐5‐nitropyridine and 2‐bromo‐5‐nitropyridine were carried out conductometrically in dimethylsulfoxide/acetonitrile mixtures. The correlation of second order rate constants with Hammett's substituent constants yields a fairly linear straight line with a negative slope. The correlation of rate data with Kamlet–Taft's solvatochromic parameters is excellent (100R2= 97%) in both the substrates. The solvation model proposed is well supported by the solvatochromism exhibited by aniline in the solvent mixture under investigation. The molar extinction coefficient (εmax ) of aniline varies appreciably up to ∼25% with the change in composition of the mixture. The multivariate correlation analysis of εmax  (with α, β, π*) suggests that the solvation around NH2 moiety of aniline through hydrogen bond donor (HBD) property is found to be dominant in the solvation process and consequently in altering the rate. The observation is that the dominance of HBD property in solvation is further confirmed by the cyclic voltammetric oxidation of aniline in the solvent mixture. © 2011 Wiley Peiodicals, Inc. Int J Chem Kinet 43: 409–417, 2011
Spiropyran‐Based Polymeric Vesicles: Preparation and Photochromic Properties
Authors: Huang Chuan‐Qun , Wang Ying , Hong Chun‐Yan , Pan Cai‐Yuan
Published: June 2011

A direct access to photochromic polymeric vesicles was demonstrated via polymerization‐induced self‐assembly and reorganization (PISR). The resulting vesicles displayed interesting photochromic behaviors different from that of their free polymer chains in DMF, and the vesicles exhibited stronger fluorescence and excellent photostability due to confinement of conformational flexibility of the polymer chains in aggregates.

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Thermosensitivity of Bile Acid‐Based Oligo(ethylene glycol) Stars in Aqueous Solutions
Authors: Strandman Satu , Le Dévédec Frantz , Zhu X. X.
Published: June 2011

Amphiphilic star‐shaped oligo(ethylene glycol)s with a hydrophobic bile acid core and varying number of hydrophilic arms have been made. Their thermal behavior in aqueous solutions depends on the number rather than the length of the arms. The two‐armed lithocholate derivative showed the strongest tendency for association and exhibited the lowest cloud point (79 °C) of the oligomers made, as well as another phase separation at a lower temperature (31 °C). The “double thermosensitivity” arising both from the salt‐dependent LCST of the oligo(ethylene glycol) segments and the temperature‐responsive self‐assembly of amphiphilic bile acid derivative provides an interesting path in the design of bile acid‐based smart materials.

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Two‐Dimensional Wang–Landau Algorithm for Osmotic Pressure Calculations in a Polyelectrolyte–Membrane System
Authors: Volkov Nikolay A. , Vorontsov‐Velyaminov Pavel N. , Lyubartsev Alexander P.
Published: June 2011

The Monte Carlo method based on two‐dimensional entropic sampling within the Wang–Landau (WL) algorithm is applied to simulation of a continuous model of a polyelectrolyte between membrane surfaces. Membranes are presented by parallel plane surfaces holding either fixed or mobile dipoles (representing lipid headgroups). A strongly charged polyion accompanied by neutralizing counterions is placed between the membranes. Periodic boundary conditions are imposed along X‐ and Y‐axes. The volume of the main cell is varied during the simulation by shifting one of the surfaces along Z‐axis. Within two‐dimensional WL sampling algorithm we obtain joint density of states as a function of energy and volume in a single run. In order to increase efficiency of our calculations we introduce a number of modifications to the original WL‐approach. Various properties of the system over wide temperature and volume or pressure ranges, i.e., conformational energy, heat capacity, and free energy, are obtained from the two‐dimensional density of states by simple integration. The osmotic pressure is calculated as a derivative of Helmholtz free energy. Alternatively, properties of the system, including average volume, can be obtained under condition of NPT ensemble. It is shown that the both approaches produce coinciding Posm(V) isotherms. In all considered cases we observe repulsive effective interaction between the membrane surfaces, and repulsion is stronger for the surfaces with fixed dipoles.

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Atomistic Molecular Dynamics Simulation of Surface Grafted PMMA
Authors: Fröhlich Markus G. , Zifferer Gerhard
Published: June 2011

Properties characteristic of the size, shape, and orientation as well as the rigidity of PMMA end‐grafted to an amorphous silica surface are calculated by use of fully atomistic molecular dynamics simulations with MMA as explicit solvent. Both the number of grafted chains and their tacticity is varied. Firstly, properties of one atactic end‐grafted chain are compared to those of the same chain without any surface being present. Secondly one, two, and four atactic grafted chains are evaluated to study the influence of grafting density (at low surface occupancy) and thirdly, results of single grafted iso‐, syndio‐, and atactic chains, respectively, are compared to elucidate the influence of tacticity. Additionally, the used force field is validated by calculation of the diffusion coefficient of solvent molecules.

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Motor cortical plasticity is impaired in Unverricht–Lundborg disease
Authors: Danner Nils , Säisänen Laura , Määttä Sara , Julkunen Petro , Hukkanen Taina , Könönen Mervi , Hyppönen Jelena , Kälviäinen Reetta , Mervaala Esa
Published: June 2011

Patients with Unverricht–Lundborg disease, also referred to as progressive myoclonus epilepsy type 1, exhibit widespread motor symptoms and signs in addition to epileptic seizures, which suggest abnormal excitability of the primary motor pathways. To explore the plasticity of the sensory–motor cortex, we employed a modern neurophysiological method, the paired associative stimulation protocol, which resembles the concept of long‐term potentiation of experimental studies. Seven patients with genetically verified Unverricht–Lundborg disease and 13 healthy control subjects were enrolled in the study to characterize cortical sensory–motor plasticity. In the study protocol, peripheral electric median nerve stimulation preceded navigated transcranial magnetic stimulation targeted to the representation area of thenar musculature on the contralateral primary motor cortex. The protocol consisted of 132 transcranial magnetic stimulation trials at 0.2 Hz, preceded by peripheral sensory stimulation at 25 ms. Motor‐evoked potential amplitudes were analyzed at baseline and after the paired associative stimulation protocol at an intensity of 130% of the individual motor threshold. The patients with Unverricht–Lundborg disease exhibited an average decrease of 15% in motor‐evoked potential amplitudes 30 minutes after paired associative stimulation, whereas in the control subjects, a significant increase (101%) was observed (P < .05), as expected. The results indicate a lack of normal cortical plasticity in Unverricht–Lundborg disease, which stresses the role of abnormal motor cortical functions or sensorimotor integration as possible pathophysiological contributors to the motor symptoms. The impaired cortical plasticity may be associated with the previously reported structural and physiological abnormalities of the primary motor cortex. © 2011 Movement Disorder Society
Self‐Efficacy as an Outcome Measure and its Association with Physical Disease‐Related Variables in Persons with Rheumatoid Arthritis: A Literature Review
Authors: Primdahl J. , Wagner L. , Hørslev‐Petersen Kim
Published: June 2011

Background

Studies have demonstrated a positive impact of patient education on self‐efficacy in persons with rheumatoid arthritis (RA). However, the relationship between self‐efficacy, physical disease‐related variables and educational interventions has not yet been reviewed.

Aim

The aims of this study, in relation to persons with RA, were: 1) to provide an overview of the existing research into the association between self‐efficacy and physical disease‐related variables and, with this knowledge, 2) to provide an overview of the existing research on the effect of different types of educational interventions on self‐efficacy.

Method

A systematic literature search was performed using eight databases, based on the terms ‘rheumatoid arthritis’ AND ‘self‐efficacy’. In total, 74 studies reporting associations between self‐efficacy and physical disease‐related variables and using self‐efficacy as an outcome measure in educational interventions were included.

Results

The scores obtained by the most commonly used questionnaire, the Arthritis Self‐Efficacy Scale (ASES), was highly associated with physical disability, pain, fatigue and disease duration. If educational activities had a positive impact on self‐efficacy, disease‐related variables usually improved as well. Evidence is scarce as to whether disease‐related variables affect patients' self‐efficacy or vice versa and whether individual consultations can affect patients' self‐efficacy.

Conclusion

The scores attained by the ASES is highly associated with physical disease‐related variables. This relationship requires further research using a specific study design to restrict bias when evaluating the impact of interventions on self‐efficacy in persons with RA. Research is needed on whether individual consultations can affect patients' self‐efficacy. Disease‐related variables do not affect the Rheumatoid Arthritis Self‐Efficacy (RASE) questionnaire but this needs further exploration. Copyright © 2011 John Wiley & Sons, Ltd.
Spezialitäten und Patentklippen
Authors: Bulmahn Maren
Published: June 2011

Ob Spezialchemikalienhersteller oder Chemikalienhandel: Etliche Unternehmen lieferten in Deutschland im letzten Jahr Rekordergebnisse. Nur die Pharmaindustrie meldete zum Teil schlechtere Werte als im Jahr zuvor. Nach den Daten der großen deutschen Chemieunternehmen folgen jetzt Jahresberichte weiterer Unternehmen und Branchen.
Abmahnen oder kündigen?
Authors: Brombach Silke , Maas Nicole
Published: June 2011

Wie reagiert ein Laborleiter, wenn sich ein Mitarbeiter nicht an die Vorschriften hält — etwa wenn er keine Arbeitsschutzkleidung trägt. Die fristlose Kündigung ist jedenfalls keine Lösung.
Characterization of the urinary bladder dysfunction in renovascular hypertensive rats
Authors: Ramos‐Filho Antonio C.S. , Mónica Fabíola Z.T. , Franco‐Penteado Carla F. , Rojas‐Moscoso Julio A. , Báu Fernando R. , Schenka André A. , De Nucci Gilberto , Antunes Edson
Published: June 2011

Aims

Association between arterial hypertension and urinary bladder dysfunction has been reported in humans and spontaneously hypertensive rats. However, no study exists evaluating the bladder dysfunction in conditions of renovascular hypertension. The purpose of this study was to characterize the bladder dysfunction in two kidney‐one clip (2K‐1C) hypertensive rats.

Methods

A silver clip was placed around the renal artery of male Wistar rats. After 8 weeks, cystometric study, concentration–response curves to contractile and relaxant agents, frequency‐dependent contractions, histomorphometry, muscarinic M2/M3 mRNA expression and cyclic AMP measurements were performed.

Results

2K‐1C rats showed enhanced bladder volume, wall thickness and smooth muscle density. 2K‐1C rats also exhibited increases in bladder capacity and non‐void contractions, and decreases in the inter‐contraction intervals. In isolated detrusor smooth muscle (DSM), contractions to carbachol and electrical‐field stimulation (EFS) were significantly greater in 2K‐1C rats. The Rho‐kinase inhibitor Y27632 (10 µM) significantly reduced the carbachol‐induced contractions in SHAM and 2K‐1C rats, but DSM remained overactive in 2K‐1C rats in presence of Y27632. Concentration‐dependent contractions to the P2X receptor agonist α,β‐methylene ATP, KCl and extracellular Ca2+ did not change between SHAM and 2K‐1C groups. In 2K‐1C rats, isoproterenol, metaproterenol and BRL 37‐344 (non‐selective, β2‐ and β3‐selective adrenoceptor agonists, respectively) produced significantly lower relaxations and decreased cAMP levels, whereas relaxant responses to sodium nitroprusside and BAY 41‐2272 remained unchanged. Muscarinic M3 mRNA expression receptors were higher in 2K‐1C group.

Conclusions

Renovascular hypertensive rats exhibit bladder dysfunction that involves tissue remodeling and enhanced muscarinic M3‐mediated contractions associated with reduced β‐adrenoceptor‐mediated signal transduction. Neurourol. Urodynam. 30:1392–1402, 2011. © 2011 Wiley‐Liss, Inc.
PSA levels in men with spinal cord injury and under intermittent catheterization
Authors: Torricelli Fabio César Miranda , Lucon Marcos , Vicentini Fabio , Gomes Cristiano Mendes , Srougi Miguel , Bruschini Homero
Published: June 2011

Aim

To evaluate serum PSA levels of patients with spinal cord injury (SCI) submitted or not to CIC in comparison to those of the general population.

Methods

We retrospectively studied 140 men with SCI admitted in our department from January 2005 to May 2009. Thirty‐four SCI patients had PSA levels available, comprising 21 under CIC and 13 without CIC. Patients under CIC performed it 4–6 times a day and mean time of catheterization was 72.4 months (range 30–192). The most common etiology of SCI was fall from height (33%), followed by car/motorcycle crashes (15%). Control group was composed by 670 healthy men that were referred to our service to evaluation of Kidney donation or cancer prostate screening. We used Student's t‐test and variance analysis (ANOVA) for age and PSA comparison between the groups.

Results

Overall, patients with SCI and controls had similar mean age (54 vs. 57 years old, P = 0.11) and mean PSA level (1.81 vs. 1.95 ng/ml, P = 0.66). SCI patients were divided into with and without CIC. Patients without CIC had similar mean age (60 vs. 57 years old, P = 0.11) and similar PSA values when compared to controls (1.72 vs. 1.95 ng/ml, P = 0.89). Patients under CIC were compared to controls with similar age (50 vs. 47 years, P = 0.0332) and their PSA levels were greater (1.86 vs. 0.79 ng/ml, P = 0.026).

Conclusion

Clean intermittent catheterization increased PSA levels approximately doubling its value. Neurourol. Urodynam. 30: 1522–1524, 2011. © 2011 Wiley Periodicals, Inc.
Not so sexy: public opinion of political sex scandals as reflected in political cartoons
Authors: Wiid Ria , Pitt Leyland F. , Engstrom Anne
Published: June 2011

An analysis of political cartoons of three well‐known US political sex scandals is presented to examine how cartoons channel public perception in terms of the involvement of a prominent politician and the difference of opinion based on who the politician is, frame the organization of communal knowledge, and facilitate the grounds upon which some things can be said.

On one side of the spectrum, theories of political cartoons presume that political cartoons reflect public attitudes about current events and that by studying cartoons surrounding a sex scandal, public attitudes toward such a scandal can be effectively understood. On the other side of the spectrum, theory argues that cartoons actually persuade and shape public attitudes, intentions, and behaviors.

Three prominent former US politicians were selected for the analysis:

Eliot Spitzer and the Emperor's Club

Bill Clinton and Monica Lewinsky

John Edwards and Rielle Hunter

The criteria of narrative, location, binary struggle, and normative transfer were used as a framework to analyze 230 cartoons. The findings suggest that some politicians emerge relatively unscathed from scandals, others are seriously condemned, yet others are obscured or have their roles changed substantially. On the basis of the research criteria, it seems that public reactions and sentiments toward politicians' involvement in a scandal depend on what the scandal was about, where it occurred and what happened there, who the protagonists in the conflict were, and who the loser in the story was. Copyright © 2011 John Wiley & Sons, Ltd.
Pancreatic exocrine function and cardiac iron in patients with iron overload and with thalassemia
Authors: Yamamura Jin , Grosse Regine , Jarisch Andrea , Janka Gritta E. , Nielsen Peter , Adam Gerhard , Fischer Roland
Published: June 2011

Patients with β‐thalassemia major at risk of cardiac iron overload have to be identified to undergo myocardial iron measurements by magnetic resonance imaging (MRI), especially, in areas and centers with restricted access to MRI. Measurements of heart iron, liver iron, and pancreatic exocrine function were performed in 44 patients by MRI‐R2* [the transverse relaxation rate R2* (= 1/T2*) characterizes the magnetic resonance decay from protons not being in phase with each other in contrast to R2 (= 1/T2)], biomagnetic liver susceptometry (LIC), and pancreatic serum amylase (PAM) and lipase (LIP), respectively. ROC analysis (area: 0.88) for detecting patients with cardiac R2* > 50 sec−1 (T2* < 20 msec) by LIP revealed a cut‐off level of 19 U/L. In conclusion, patients at risk of elevated cardiac iron levels could be identified by the exocrine pancreatic lipase and amylase function parameters. Pediatr Blood Cancer 2011; 57: 674–676. © 2011 Wiley‐Liss, Inc.
Proteomic analysis of outer membrane vesicles derived from Pseudomonas aeruginosa
Authors: Choi Dong‐Sic , Kim Dae‐Kyum , Choi Seng Jin , Lee Jaewook , Choi Jun‐Pyo , Rho Sangchul , Park Sang‐Hyun , Kim Yoon‐Keun , Hwang Daehee , Gho Yong Song
Published: June 2011

Pseudomonas aeruginosa, an opportunistic human bacterial pathogen, constitutively secretes outer membrane vesicles (OMVs) into the extracellular milieu. Although recent progress has revealed that OMVs are essential for pathogenesis of P. aeruginosa, their proteins have not been comprehensively analyzed so far. In this study, we identified 338 vesicular proteins with high confidence by five separate LC‐MS/MS analyses. This global proteome profile provides a basis for future studies to elucidate the pathological functions of OMVs from P. aeruginosa.
New protein isoforms identified within Arabidopsis thaliana seed oil bodies combining chymotrypsin/trypsin digestion and peptide fragmentation analysis
Authors: Vermachova Martina , Purkrtova Zita , Santrucek Jiri , Jolivet Pascale , Chardot Thierry , Kodicek Milan
Published: June 2011

Plant seed oil bodies, subcellular lipoprotein inclusions providing storage reserves, are composed of a neutral lipid core surrounded by a phospholipid monolayer with several integrated proteins that play a significant role in stabilization of the particles and probably also in lipid mobilization. Oil bodies' proteins are generally very hydrophobic, due to the long uncharged sequences anchoring them into the lipid core, which makes them extremely difficult to handle and to digest successfully. Although oil bodies have been intensively studied during last decades, not all their proteins have been identified yet. To overcome the problems connected with their identification, a method based on SDS‐PAGE, in‐gel digestion and LC‐MS/MS analysis was used. Digestion was carried out with trypsin and chymotrypsin, single or in combination, which increased significantly the number of identified peptides, namely the hydrophobic ones. Thanks to this methodology it was possible to achieve an extensive coverage of proteins studied, to analyze their N‐terminal modifications and moreover, to detect four new oil bodies' protein isoforms, which demonstrates the complexity of oil bodies' protein composition.
Proteome characterization of sea star coelomocytes – The innate immune effector cells of echinoderms
Authors: Franco Catarina F. , Santos Romana , Coelho Ana V.
Published: June 2011

Sea star coelomic fluid is in contact with all internal organs, carrying signaling molecules and a large population of circulating cells, the coelomocytes. These cells, also known as echinoderm blood cells, are responsible for the innate immune responses and are also known to have an important role in the first stage of regeneration, i.e. wound closure, necessary to prevent disruption of the body fluid balance and to limit the invasion of pathogens. This study focuses on the proteome characterization of these multifunctional cells. The identification of 358 proteins was achieved using a combination of two techniques for protein separation (1‐D SDS‐PAGE followed by nanoLC and 2‐D SDS‐PAGE) and MALDI‐TOF/TOF MS for protein identification. To our knowledge, the present report represents the first comprehensive list of sea star coelomocyte proteins, constituting an important database to validate many echinoderm‐predicted proteins. Evidence for new pathways in these particular echinoderm cells are also described, and thus representing a valuable resource to stimulate future studies aiming to unravel the homology with vertebrate immune cells and particularly the origins of the immune system itself.
Adamantyl‐endcapped polyynes
Authors: Chalifoux Wesley A. , Ferguson Michael J. , McDonald Robert , Melin Frederic , Echegoyen Luis , Tykwinski Rik R.
Published: June 2011

Polyynes spanning from a diyne to a dodecayne with adamantyl endgroups have been synthesized using the Fritsch–Buttenberg–Wiechell rearrangement as a key step to construct the acetylenic framework. Molecular properties as a function of polyyne length have been analyzed by UV–Vis spectroscopy, cyclic voltammetry, differential scanning calorimetry, and X‐ray crystallography. Copyright © 2011 John Wiley & Sons, Ltd.
Investigating the provenance of un‐dyed spun cotton fibre using multi‐isotope profiles and chemometric analysis
Authors: Daéid Niamh Nic , Meier‐Augenstein Wolfram , Kemp Helen F.
Published: June 2011

The analysis of un‐dyed spun cotton fibres can be challenging within a forensic science context where discrimination of one fibre from another is of importance. Conventional microscopic and chemical analysis of these fibres is generally unsuccessful because of their similar morphology. In this work we have explored the potential of isotope ratio mass spectrometry (IRMS) as a tool for spun cotton fibre analysis in an attempt to reveal any discriminatory information available. Seven different batches of un‐dyed spun cotton fibre from four different countries were analysed. A combination of the hydrogen and oxygen isotopic data facilitated the correct association of the samples, demonstrating, for the first time, the applicability of IRMS to fibre analysis in this way. Copyright © 2011 John Wiley & Sons, Ltd.
Identification of unsaturated N‐acylhomoserine lactones in bacterial isolates of Rhodobacter sphaeroides by liquid chromatography coupled to electrospray ionization‐hybrid linear ion trap‐Fourier transform ion cyclotron resonance mass spectrometry
Authors: Cataldi Tommaso R. I. , Bianco Giuliana , Abate Salvatore , Losito Ilario
Published: June 2011

The identification of two unsaturated N‐acylhomoserine lactones (AHLs) produced by Rhodobacter sphaeroides bacteria, based on liquid chromatography (LC) coupled to a hybrid quadrupole linear ion trap (LTQ)‐Fourier transform ion cyclotron resonance (FTICR) mass spectrometer upon electrospray ionization (ESI), is presented. Besides the confirmation of the signaling molecule already described in the literature, i.e. (Z)‐N‐tetradec‐7‐enoyl‐homoserine lactone (C14:1‐HSL), we have discovered the occurrence, at low, yet significant levels, of another monounsaturated compound, C12:1‐HSL, which may extend the number of small diffusible chemical signals known for R. sphaeroides. Both unsaturated AHLs were identified by high‐resolution FTICR mass spectrometry in extracts of bacterial culture media and the occurrence of a C=C bond was assessed upon their conversion into bromohydrins. Collision‐induced dissociation (CID) spectra were then collected on the LTQ mass analyzer. A careful comparison of tandem MS spectra of monounsaturated (i.e., C12:1‐HSL and C14:1‐HSL) and saturated AHLs (i.e. C12‐HSL and C14‐HSL) led to the emphasis of two series of product ions, exhibiting 14 Da spaced m/z ratios. Both series were referred to progressive fragmentations at the aliphatic end of the AHL acyl chains, followed by neutral losses of terminal alkenes (i.e. CH2=CH(CH2)nH). In particular, the series located at the higher end of the explored m/z range (>200 Da), observed only for monounsaturated species, enabled the location of the C=C bond between carbons 7 and 8 of the acyl chain. Copyright © 2011 John Wiley & Sons, Ltd.
Efficient enrichment and identification of phosphopeptides by cerium oxide using on‐plate matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometric analysis
Authors: Sun Shutao , Ma Haitao , Han Guanghui , Wu Ren'an , Zou Hanfa , Liu Yiwei
Published: June 2011

An efficient and simple method for enrichment and identification of phosphopeptides by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) using cerium oxide is presented. After pretreatment of tryptic digests of phosphoproteins with CeO2, nonphosphopeptides are discarded and phosphopeptides are enriched. By applying the separated CeO2 on a target plate and analysis using MALDI‐TOF MS, peaks of phosphopeptides and their correspondingly series of dephosphorylated peptides are observed in the mass spectra. Thus, the phosphopeptides are very easy to identify with the mass difference, which are all 80 Da between adjacent peaks in the same series, and clear background in the spectra owing to elimination of signal suppression from large amounts of nonphosphopeptides. Furthermore, the phosphopeptides can be dephosphorylated completely after a further NH4OH elution. Tryptic digest products from several standard proteins are pretreated using CeO2 to demonstrate the efficiency of this method. Phosphopeptides from a very small quantity of human serum are enriched and analyzed, and proteins also identified by searching against a database using Mascot on MALDI‐TOF/TOF fragments, which indicates that this method may be employed in complex samples for further application. Copyright © 2011 John Wiley & Sons, Ltd.