bluuebunny/crossref_metadata_2025 huggingface dataset:
Differentiation of human thymic regulatory T cells at the double positive stage
Authors: Nunes‐Cabaço Helena , Caramalho Íris , Sepúlveda Nuno , Sousa Ana E.
Published: September 2011

Treg cells, best identified by the expression of the transcription factor FOXP3, play a crucial role in maintaining self‐tolerance. Natural Treg cells constitute an independent thymus‐derived T‐cell lineage whose developmental program in humans is still ill‐defined. Here, we provide evidence of a Treg‐cell differentiation pathway at the double positive (DP) stage, prior to commitment to the CD4+ or CD8+ lineage, in pediatric thymuses. FOXP3+ DP cells displayed a functional IL‐7 receptor and increased Bcl‐2 levels that may protect them from cell death/negative selection, and an activated/suppressive phenotype that was lost as CD4 single positive (SP) cells matured and acquired egress markers. A subpopulation of FOXP3+ DP thymocytes expressing CD103 likely represents the precursor of FOXP3+ CD8SP cells, which homogeneously expressed this mucosal‐homing molecule. Finally, co‐cultures of DP thymocytes with primary thymic epithelial cells and multiple linear regression analyses support that FOXP3+ SP cells are largely derived from FOXP3+ DP thymocytes. Overall, our data suggest that human Treg‐cell lineage commitment significantly occurs at the DP stage with possible implications for the diversity and autoreactivity of the natural Treg‐cell repertoire.
Optimizing HIV‐1‐specific CD8+ T‐cell induction by recombinant BCG in prime‐boost regimens with heterologous viral vectors
Authors: Hopkins Richard , Bridgeman Anne , Bourne Charles , Mbewe‐Mvula Alice , Sadoff Jerald C. , Both Gerald W. , Joseph Joan , Fulkerson John , Hanke Tomáš
Published: September 2011

The desire to induce HIV‐1‐specific responses soon after birth to prevent breast milk transmission of HIV‐1 led us to propose a vaccine regimen which primes HIV‐1‐specific T cells using a recombinant Mycobacterium bovis bacillus Calmette‐Guérin (rBCG) vaccine. Because attenuated live bacterial vaccines are typically not sufficiently immunogenic as stand‐alone vaccines, rBCG‐primed T cells will likely require boost immunization(s). Here, we compared modified Danish (AERAS‐401) and Pasteur lysine auxotroph (222) strains of BCG expressing the immunogen HIVA for their potency to prime HIV‐1‐specific responses in adult BALB/c mice and examined four heterologous boosting HIVA vaccines for their immunogenic synergy. We found that both BCG.HIVA401 and BCG.HIVA222 primed HIV‐1‐specific CD8+ T‐cell‐mediated responses. The strongest boosts were delivered by human adenovirus‐vectored HAdV5.HIVA and sheep atadenovirus‐vectored OAdV7.HIVA vaccines, followed by poxvirus MVA.HIVA; the weakest was plasmid pTH.HIVA DNA. The prime‐boost regimens induced T cells capable of efficient in vivo killing of sensitized target cells. We also observed that the BCG.HIVA401 and BCG.HIVA222 vaccines have broadly similar immunologic properties, but display a number of differences mainly detected through distinct profiles of soluble intercellular signaling molecules produced by immune splenocytes in response to both HIV‐1‐ and BCG‐specific stimuli. These results encourage further development of the rBCG prime‐boost regimen.
Oxidovanadium(IV) Complexes of Tetradentate Ligands Encapsulated in Zeolite‐Y as Catalysts for the Oxidation of Styrene, Cyclohexene and Methyl Phenyl Sulfide
Authors: Maurya Mannar R. , Saini Priyanka , Kumar Amit , Costa Pessoa João
Published: September 2011

The reaction of oxidovanadium(IV)‐exchanged zeolite‐Y with N,N′‐ethylenebis(pyridoxyliminato) (H2pydx‐en, I), N,N′‐propylenebis(pyridoxyliminato) (H2pydx‐1,3‐pn, II) and H2pydx‐1,2‐pn (III) in methanol heated at reflux leads to the formation of the corresponding complexes, abbreviated herein as [VIVO(pydx‐en)]‐Y (4), [VIVO(pydx‐1,3‐pn)]‐Y (5) and [VIVO(pydx‐1,2‐pn)]‐Y (6) in the supercages of zeolite‐Y. The neat complexes [VIVO(pydx‐en)] (1), [VIVO(pydx‐1,3‐pn)] (2) and [VIVO(pydx‐1,2‐pn)] (3) were also prepared. Spectroscopic studies (IR, UV/Vis and EPR), elemental analyses, thermal studies, field‐emission scanning electron micrographs (FESEM) and X‐ray diffraction patterns were used to characterize these complexes. Oxidations of styrene, cyclohexene and methyl phenyl sulfide were investigated using these complexes as catalyst precursors in the presence of H2O2 as oxidant. Under the optimized reaction conditions, a maximum of 85.5 % conversion of styrene was obtained with 4, 84.6 % conversion with 5 and 82.9 % conversion with 6 in 6 h of reaction time. The selectivity of the various products was similar for the catalyst precursors 4–6 and followed the order: benzaldehyde > 1‐phenylethane‐1,2‐diol > benzoic acid > phenyl acetaldehyde. With cyclohexene, a maximum conversion of 95.9 % was achieved with 4, 94.5 % with 5 and 94.2 % conversion with 6, also in 6 h of reaction time. The selectivity of the various products was similar for the three catalysts: 2‐cyclohexen‐1‐one > 2‐cyclohexen‐1‐ol > cyclohexane‐1,2‐diol. The oxidation of methyl phenyl sulfide was achieved with 4, 5 and 6 in 2.5 h of reaction time with 85.5, 82.1 and 80 % conversion, with higher selectivity towards sulfoxide. Overall, the encapsulated catalysts were significantly more active than their neat counterparts and have the further advantage of being recyclable. No relevant difference in activity was found due to a change in the diamine in the Schiff base ligands I–III. UV/Vis and 51V NMR spectroscopic experiments with 1 confirmed the plausible formation of VVO(O2)L as intermediates in the catalytic oxidations.
Steric Course of the Electrophilic Substitution of a Lithiocarbanion Generated from (S,E)‐1‐Phenylbut‐2‐en‐1‐yl Diisopropylcarbamate and Solvent Effects
Authors: Ikemoto Hidaka , Sasaki Michiko , Kawahata Masatoshi , Yamaguchi Kentaro , Takeda Kei
Published: September 2011

The effects of electrophiles and solvents on the stereochemistry of electrophilic substitution of a lithiocarbanion generated from (S,E)‐1‐phenylbut‐2‐en‐1‐yl diisopropylcarbamate were examined using various acids and carbon electrophiles. The stereochemical outcomes were influenced by the relative ability of the electrophiles and solvents to coordinate to lithium.
Copper(II)‐Mediated Intramolecular Cyclization of (Z)‐Chalcogenoenynes: Synthesis of 3‐Halochalcogenophene Derivatives
Authors: Barancelli Daniela A. , Schumacher Ricardo F. , Leite Marlon R. , Zeni Gilson
Published: September 2011

We present our results on the cyclization of (Z)‐chalcogenoenynes mediated by copper(II) salts to afford 3‐halochalcogenophenes in satisfactory yields through an intramolecular 5‐endo‐dig cyclization. The methodology was carried out using CuCl2 at 50 °C or CuBr2 at room temperature under an ambient atmosphere. The reaction took place under very mild reaction conditions and tolerated considerable functionality. One 3‐bromo‐selenophene derivative was applied as a substrate in the palladium‐catalyzed cross‐coupling reaction with a boronic acid to give the Suzuki type product in good yield.
CuII–β‐Cyclodextrin Complex as a Nanocatalyst for the Homo‐ and Cross‐Coupling of Arylboronic Acids under Ligand‐ and Base‐Free Conditions in Air: Chemoselective Cross‐Coupling of Arylboronic Acids in Water
Authors: Kaboudin Babak , Abedi Yaghoub , Yokomatsu Tsutomu
Published: September 2011

We report here the transition‐metal‐catalyzed chemoselective cross‐coupling of arylbroronic acids in high yields without using ligand or base. We have developed an efficient copper‐catalyzed protocol for the homocoupling and cross‐coupling of arylboronic acids. The protocol is also suitable for the cross‐coupling of aliphatic primary amines with arylboronic acids. Aminophenols and primary amines bearing an alcoholic substituent on the aliphatic chain were coupled with arylboronic acids, and the products were obtained with high C–N coupling selectivity. An effective catalyst was Cu2–β‐cyclodextrin, which is readily available and structurally simple, but has not previously been explored as a catalyst.
Efficient Synthesis of DNA Conjugates by Strain‐Promoted Azide–Cyclooctyne Cycloaddition in the Solid Phase
Authors: Singh Ishwar , Freeman Colin , Heaney Frances
Published: September 2011

Conjugation of ligands to DNA oligonucleotides has been achieved in the solid phase by strain‐promoted azide–alkyne cycloaddition (SPAAC). The oligonucleotide, modified with a simple nonfluroinated, monocyclic octyne, efficiently forms conjugates with a range of azide dipoles with varying steric and electronic characteristics. The reaction is clean and easily executed in a copper free environment at room temperature. It provides a variety of triazole‐linked nucleic acid conjugates and is potentially useful in biotechnology and cell biology.
Treatment of Chronic Hepatitis C Genotype 1 Patients at An Academic Center in Europe Involved in Prospective, Controlled Trials
Authors: Beinhardt Sandra , Staettermayer Albert F. , Rutter Karoline , Maresch Judith , Scherzer Thomas M. , Steindl–Munda Petra , Hofer Harald , Ferenci Peter
Published: September 2011

Pegylated interferon–alpha2/ribavirin (peg–IFN/RBV) is the standard of care (SOC) for patients with chronic hepatitis C (CHC) infection. Currently, direct–acting antiviral agents (DAAs) are evaluated in clinical trials. The aim of this study was to compare baseline characteristics and sustained virologic response (SVR) rates in patients included in clinical trials to those receiving SOC. Medical records of all 503 treatment–naïve patients with CHC, genotype (GT) 1, referred over a 4–year period (January 2006–December 2009) were reviewed. Only 310 of 503 (62%) patients received antiviral therapy, 141 were enrolled in randomized, controlled trials (“study patients”; 101 in DAA studies), and 169 received SOC. At baseline, viral load and platelet count were higher and bilirubin was lower in study patients than in SOC patients. History of psychiatric disorders was more common in SOC patients (43 [25%] versus study patients with 18 [13%];

P

< 0.01). Liver biopsy was obtained in 98% of study patients, but only in 59% of SOC patients. Twenty–nine (21%) and 40 (40%) study and SOC patients, respectively, had advanced fibrosis (F3/4;

P

= 0.001). By intent–to–treat analysis, SVR rates were higher in DAAs (64%; 95% confidence interval [CI]: 53.4–74.4) than in SOC patients (46%; 95% CI: 37.9–53.7;

P

< 0.01), but not different when calculated on a treated–per–protocol (TPP) basis. Interleukin (IL)28B GT was equally distributed in both cohorts. By chance, more patients treated with IFN/RBV had rs12979860 C/C–GT (up to 44%) than DAA–treated patients. If analyzed according to the IL28B polymorphism, TPP SVR rates did not reach statistically significant differences among study and SOC patients.

Conclusions:

Baseline characteristics slightly favored study patients, but IL28B GT and treatment adherence were the most important factors determining outcome. Thus, the applicability of the results of controlled studies has to be tested in a “real–world” setting. (Hepatology 2012
Conjugated Bile Acids Activate the Sphingosine–1–Phosphate Receptor 2 in Primary Rodent Hepatocytes
Authors: Studer Elaine , Zhou Xiqiao , Zhao Renping , Wang Yun , Takabe Kazuaki , Nagahashi Masayuki , Pandak William M. , Dent Paul , Spiegel Sarah , Shi Ruihua , Xu Weiren , Liu Xuyuan , Bohdan Pat , Zhang Luyong , Zhou Huiping , Hylemon Phillip B.
Published: September 2011

Bile acids have been shown to be important regulatory molecules for cells in the liver and gastrointestinal tract. They can activate various cell signaling pathways including extracellular regulated kinase (ERK)1/2 and protein kinase B (AKT) as well as the G–protein–coupled receptor (GPCR) membrane–type bile acid receptor (TGR5/M–BAR). Activation of the ERK1/2 and AKT signaling pathways by conjugated bile acids has been reported to be sensitive to pertussis toxin (PTX) and dominant–negative Gαi in primary rodent hepatocytes. However, the GPCRs responsible for activation of these pathways have not been identified. Screening GPCRs in the lipid–activated phylogenetic family (expressed in HEK293 cells) identified sphingosine–1–phosphate receptor 2 (S1P2) as being activated by taurocholate (TCA). TCA, taurodeoxycholic acid (TDCA), tauroursodeoxycholic acid (TUDCA), glycocholic acid (GCA), glycodeoxycholic acid (GDCA), and S1P–induced activation of ERK1/2 and AKT were significantly inhibited by JTE–013, a S1P2 antagonist, in primary rat hepatocytes. JTE–013 significantly inhibited hepatic ERK1/2 and AKT activation as well as short heterodimeric partner (SHP) mRNA induction by TCA in the chronic bile fistula rat. Knockdown of the expression of S1P2 by a recombinant lentivirus encoding S1P2 shRNA markedly inhibited the activation of ERK1/2 and AKT by TCA and S1P in rat primary hepatocytes. Primary hepatocytes prepared from S1P2 knock out (S1P2
−/−) mice were significantly blunted in the activation of the ERK1/2 and AKT pathways by TCA. Structural modeling of the S1P receptors indicated that only S1P2 can accommodate TCA binding. In summary, all these data support the hypothesis that conjugated bile acids activate the ERK1/2 and AKT signaling pathways primarily through S1P2 in primary rodent hepatocytes. (Hepatology 2012)
Zinc supplementation augments in vivo antitumor effect of chemotherapy by restoring p53 function
Authors: Margalit Ofer , Simon Amos J. , Yakubov Eduard , Puca Rosa , Yosepovich Ady , Avivi Camila , Jacob‐Hirsch Jasmine , Gelernter Ilana , Harmelin Alon , Barshack Iris , Rechavi Gideon , D'Orazi Gabriella , Givol David , Amariglio Ninette
Published: September 2011

Activated p53 is necessary for tumor suppression. Homeodomain‐interacting protein kinase‐2 (HIPK2) is a positive regulator of functional p53. HIPK2 modulates wild‐type p53 activity toward proapoptotic transcription and tumor suppression by the phosphorylation of serine 46. Knock‐down of HIPK2 interferes with tumor suppression and sensitivity to chemotherapy. Combined administration of adriamycin and zinc restores activity of misfolded p53 and enables the induction of its proapoptotic and tumor suppressor functions in vitro and in vivo. We therefore looked for a cancer model where HIPK2 expression is low. MMTV‐neu transgenic mice overexpressing HER2/neu, develop mammary tumors at puberty with a long latency, showing very low expression of HIPK2. Here we show that whereas these tumors are resistant to adriamycin treatment, a combination of adriamycin and zinc suppresses tumor growth in vivo in these mice, an effect evidenced by the histological features of the mammary tumors. The combined treatment of adriamycin and zinc also restores wild‐type p53 conformation and induces proapoptotic transcription activity. These findings may open up new possibilities for the treatment of human cancers via the combination of zinc with chemotherapeutic agents, for a selected group of patients expressing low levels of HIPK2, with an intact p53. In addition, HIPK2 may serve as a new biomarker for tumor aggressiveness.
MR elastography for noninvasive assessment of hepatic fibrosis: Experience from a tertiary center in asia
Authors: Kim Bo Hee , Lee Jeong Min , Lee Ye Ji , Lee Kyoung Bun , Suh Kyung‐Suk , Han Joon Koo , Choi Byung Ihn
Published: September 2011

Purpose:

To determine the sensitivity and specificity of MR elastography (MRE) in the staging of hepatic fibrosis (HF) using histopathology as the reference standard in an Asian population.

Materials and Methods:

MRE was performed on 55 patients with chronic liver diseases or biliary diseases and on 5 living related liver donors (48 men and 12 women; mean age, 55.7 years). MRE was performed with modified, phase‐contrast, gradient‐echo sequences, and the mean stiffness values were measured on the elastograms in kilopascals(kPa). Receiver operating characteristic curve analysis was performed to determine the cutoff value and accuracy of MRE for staging HF. Histopathologic staging of HF according to the METAVIR scoring system served as the reference.

Results:

Liver stiffness increased systematically along with the fibrosis stage. With a shear stiffness cutoff value of 3.05 kPa, the predicted sensitivity and specificity for differentiating significant liver fibrosis (≥ F2) from mild fibrosis (F1) were 89.7% and 87.1%, respectively. In addition, MRE was able to discriminate between patients with severe fibrosis (F3) and those with liver cirrhosis (sensitivity, 100%; specificity, 92.2%), with a shear stiffness cutoff value of 5.32 kPa.

Conclusion:

MRE could be a promising, noninvasive technique with excellent diagnostic accuracy for detecting significant HF and liver cirrhosis. J. Magn. Reson. Imaging 2011. © 2011 Wiley Periodicals, Inc.
Kinetics of elementary steps in the reaction of atomic bromine with 2,3‐dimethyl‐2‐butene under atmospheric conditions
Authors: Laine Patrick L. , Sohn Yoon S. , Nicovich J. Michael , Mckee Michael L. , Wine Paul H.
Published: September 2011

We have employed the laser flash photolysis–resonance fluorescence technique to investigate the gas‐phase kinetics of elementary steps in the Br‐initiated oxidation of 2,3‐dimethyl‐2‐butene (TME) under atmospheric conditions. At T⩾ 274 K, measured rate coefficients are independent of pressure suggesting hydrogen abstraction as the dominant pathway. The following Arrhenius expression adequately describes all kinetic data at 274 K ⩽T⩽ 420 K: k1a(T) = (3.84 ± 0.84) × 10− 11 exp[(−169 ± 61)/T] cm3 molecule−1s−1 (uncertainties are 2σ, precision only). At 203 K ⩽T⩽ 241 K, kinetic evidence for reversible addition, Br + TME ↔ Br−TME (k1b, k−1b), is observed. Analysis of the approach to equilibrium data allows evaluation of the rate coefficients k1b and k−1b. At atmospheric pressure addition of Br to TME occurs at a near gas kinetic rate. Equilibrium constants are obtained from k1b/k−1b. Combining the experimental results with electronic structure calculations allows third‐law analyses of the equilibrium data. The following thermochemical parameters for the addition reaction (1b) at 0 and 298 K are obtained (standard state = 1 atm): ΔrH0= −47.1 ± 3.0 kJ mol−1, ΔrH298=−47.3 ± 3.0 kJ mol−1, and ΔrS298=−101.5 ± 10.0 J mol−1 K−1. Examination of the effect of added O2 on Br atom kinetics under conditions where reversible adduct formation is observed allows determination of the rate coefficient for the Br–TME + O2 reaction (k2). At 223 K, we find that k2 increases from 3.9 to 5.5 × 10−12 cm3 molecule−1s−1 as pressure increases from 25 to 200 Torr. Our results suggest that under most atmospheric conditions the Br–TME reaction with O2 occurs more rapidly than the Br–TME unimolecular decomposition. Hence, the fast addition reaction appears to control the rate of TME loss by reaction with Br in the atmosphere. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 44: 13–26, 2012
Tracking the contour
Authors: Franz Christoph , Singpiel Holger , Trein Johannes
Published: September 2011

In recent years the use of modern solid‐state lasers has brought about a distinct increase in operational speed in laser materials processing. Whether with scanners or fixed optics, high speeds – as far as possible in various axes at the same time – have almost become the norm. But although the movement of the optic is precisely calculated, the position of the processing point can deviate from the planned contour. Help is at hand, thanks to a process monitoring system developed by Fraunhofer ILT which precisely tracks the relative movement of work piece and optic. It enables acceleration related deviations from the set contour and speed to be measured exactly and the numerical control system to be adjusted accordingly. The kinematics measurement can be adapted to most laser processes (e.g. welding, brazing, cutting, selective laser melting, etc.) as an optional metrology method.
Rewritable and Non‐Volatile Memory Effects Based on Polyimides Containing Pendant Carbazole and Triphenylamine Groups
Authors: Li Yueqin , Fang Runchen , Ding Shijin , Shen Yingzhong
Published: September 2011

As part of a strategy to explore highly functionalized macromolecular semiconductors, two novel polyimides consisting of electron‐donating carbazole and triphenylamine side groups are synthesized and characterized. Polyimide films sandwiched between an indium‐tin oxide (ITO) bottom electrode and Al top electrode exhibit two accessible conductivity states and can be switched from the low‐conductivity state to the high‐conductivity state. Memory devices with the configuration of Al/PI(CzBD‐DPBPDA)/ITO exhibit bipolar flash‐type memory characteristics while that of Al/PI(TPABD‐DPBPDA)/ITO demonstrate excellent unipolar ON and OFF switching behavior. Both devices show high ON/OFF current ratios up to 104 and long retention times of 104 s in ambient atmosphere.
Beneficial effects of albuterol in congenital endplate acetylcholinesterase deficiency and Dok‐7 myasthenia
Authors: Liewluck Teerin , Selcen Duygu , Engel Andrew G.
Published: September 2011

Introduction: Congenital myasthenic syndromes (CMS) are disabling but treatable disorders. Anticholinesterase therapy is effective in most of them, but is contraindicated in endplate (EP) acetylcholinesterase (AChE) deficiency, the slow‐channel syndrome, Dok‐7 myasthenia, and β2‐laminin deficiency, and is not useful in CMS due to defects in muscle‐specific kinase (MuSK), agrin, and plectin. EP AChE, Dok‐7, and β2‐laminin deficiencies respond favorably to ephedrine, but ephedrine can no longer be prescribed in the USA. Methods: We used albuterol, another sympathomimetic agent, to treat 3 patients with EP AChE deficiency and 15 with Dok‐7 myasthenia. Response to therapy was evaluated by a 9‐point questionnaire pertaining to activities of daily life. Results: Comparison of the pre‐ and posttreatment responses indicated a beneficial response to albuterol (P < 0.001) in both patient groups. The adverse effects of therapy were like those of ephedrine. Conclusion: Our observations should spur controlled, prospective clinical trials of albuterol in these as well as other CMS. Muscle Nerve, 2011
Frequency domain analysis of acoustic wave propagation in heterogeneous media considering iterative coupling procedures between the method of fundamental solutions and Kansa's method
Authors: Soares Delfim , Godinho Luís , Pereira Andreia , Dors Cleberson
Published: September 2011

Acoustic wave propagation in heterogeneous media is a topic of significant interest in many areas of science and engineering, including aeroacoustics and sound propagation in oceans. In the present work, numerical frequency domain models based on the joint use of the method of fundamental solutions and of the radial basis function collocation method (also known as Kansa's method) are discussed. In this context, the method of fundamental solutions is used to model the homogeneous part of the propagation domain, while Kansa's method is employed to model the presence of heterogeneities. The coupling between the two parts of the propagation domain is performed iteratively, allowing independent spatial discretization between the different subdomains of the model (i.e. matching collocation points at common surfaces are not necessary). Additionally, an optimised algorithm, based on the use of a varying relaxation parameter, is employed to speed up and/or to ensure the convergence of the iterative coupling process. At the end of the paper, numerical results illustrate the applicability and potentialities of the proposed formulations. Copyright © 2011 John Wiley & Sons, Ltd.
Identifying transient protein–protein interactions in EphB2 signaling by blue native PAGE and mass spectrometry
Authors: Darie Costel C. , Deinhardt Katrin , Zhang Guoan , Cardasis Helene S. , Chao Moses V. , Neubert Thomas A.
Published: September 2011

Receptor tyrosine kinases (RTKs) are proteins that upon ligand stimulation undergo dimerization and autophosphorylation. Eph receptors (EphRs) are RTKs that are found in different cell types, from both tissues that are developing and from mature tissues, and play important roles in the development of the central nervous system and peripheral nervous system. EphRs also play roles in synapse formation, neural crest formation, angiogenesis and in remodeling the vascular system. Interaction of EphRs with their ephrin ligands lead to activation of signal transduction pathways and formation of many transient protein–protein interactions that ultimately leads to cytoskeletal remodeling. However, the sequence of events at the molecular level is not well understood. We used blue native PAGE and MS to analyze the transient protein–protein interactions that resulted from the stimulation of EphB2 receptors by their ephrinB1‐Fc ligands. We analyzed the phosphotyrosine‐containing protein complexes immunoprecipitated from the cell lysates of both unstimulated (−) and ephrinB1‐Fc‐stimulated (+) NG108 cells. Our experiments allowed us to identify many signaling proteins, either known to be part of EphB2 signaling or new for this pathway, which are involved in transient protein–protein interactions upon ephrinB1‐Fc stimulation. These data led us to investigate the roles of proteins such as FAK, WAVEs and Nischarin in EphB2 signaling.
Effects of hydration and hydrophilicity on Na‐Clay‐supported aqueous‐phase catalysis for atom transfer radical polymerization
Authors: Aggarwal Ravi , Baskaran Durairaj
Published: September 2011

Hydrated sodium montmorillonite (Na‐clay) has been used as a catalyst support for the heterogeneous atom transfer radical polymerization of benzyl methacrylate in the presence of various concentrations of water, reducing agent, and CuBr2 in anisole at ambient temperature. The polymerization was promoted via reduction of CuII to CuI through the addition of sodium ascorbate (NaAsc) as a reducing agent in aqueous solution. The polymerizaton proceeded in a controlled manner and produced poly(benzyl methacylate) with moderately narrow molecular weight distribution (MWD) when performed under optimum conditions of hydration (10 wt % ≤ H2O/Na‐clay ≤ 21 wt %) and reducing agent (0.15 ≤ [NaAsc]/[I] ≤ 0.23). The polymerization was uncontrolled if hydration and NaAsc exceed above their optimum range of concentrations. Apparent rate of the polymerization (kapp) increased in the presence of decane–anisole (1/3, v/v) mixture solvent. Selective adsorption of decane at the interfaces of the hydrated clay was attributed for the rate enhancement due to increased polymer and hydrophobic interface interaction. The polymerization progressed in a controlled manner as confirmed by the first‐order time‐conversion plot, linear increase in molecular weights, and moderately narrow MWDs over conversion. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Development of high‐performance networked polymers consisting of isocyanurate structures based on selective cyclotrimerization of isocyanates
Authors: Moritsugu Masaki , Sudo Atsushi , Endo Takeshi
Published: September 2011

Selective and quantitative cyclotrimerization of p‐tolylisocyanate proceeded by using sodium p‐toluenesulfinate as a catalyst and 1,3‐dimethylimidazolidinone as a solvent. Exploitation of this system to the cyclotrimerization of methylene diphenyl 4,4′‐diisocyanate (MDI) permitted formation of the corresponding networked polymer, which was selectively consisted of isocyanurate moiety and thus exhibited excellent thermal stability. Utilization of phenyl isocyanate (PhNCO) as a comonomer with varying feed ratio [MDI]0/[PhNCO]0 allowed successful control of flexibility of the networked polymers, while retaining its high thermal stability. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Controlled polymerization of epoxides: Metal‐free ring‐opening polymerization of glycidyl phenyl ether initiated by tetra‐n‐butylammonium fluoride in the presence of protic compounds
Authors: Morinaga Hisatoyo , Ujihara Yusuke , Yuto Naho , Nagai Daisuke , Endo Takeshi
Published: September 2011

Metal‐free controlled ring‐opening polymerization of glycidyl phenyl ether (GPE) was achieved using tetra‐n‐butylammonium fluoride (Bu4NF) as an initiator in the presence of water and ethanol as chain transfer agents (CTAs). Number‐averaged molecular weight of poly(GPE) increased with an increase of [GPE]0/([Bu4NF]0 + [CTA]0) values, showing relatively narrow molecular weight distributions. NMR spectroscopic analysis exhibited a formation of ethoxy groups as well as FCH2 at the initiating polymer chain‐end when ethanol was used as the CTA in the polymerization. These results indicate that Bu4NF acts as a catalyst as well as the initiator for this polymerization system. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Identifying how and for whom cognitive‐behavioral stress management improves emotional well‐being among recent prostate cancer survivors
Authors: Traeger Lara , Penedo Frank J. , Benedict Catherine , Dahn Jason R. , Lechner Suzanne C. , Schneiderman Neil , Antoni Michael H.
Published: September 2011

Objective

The outcomes of a 10‐week cognitive‐behavioral stress management (CBSM) group intervention were evaluated in prostate cancer survivors. A model was tested in which CBSM‐related improvements in emotional well‐being were attained through changes in men's perceptions of their condition, as conceptualized by information processing explanations of self‐regulation theory. The model also tested whether life stress and treatment‐related side effects moderated intervention effects.

Methods

Men treated for localized prostate cancer (n = 257) within the past 18 months were randomized to CBSM or a half‐day psycho‐educational seminar. At pre‐intervention and 12‐week follow‐up, emotional well‐being, illness perceptions, life stress, and sexual and urinary function were assessed using validated questionnaires.

Results

After controlling for covariates, CBSM participants showed greater improvements in emotional well‐being relative to control participants (β = 0.13, p < 0.05). For men reporting higher stress upon study entry, CBSM‐related improvements were partially explained by changes in some, but not all, illness perceptions. Sexual and urinary dysfunction did not influence CBSM‐related gains.

Conclusions

Prostate cancer perceptions may be an important target for enhancing emotional well‐being, particularly for men experiencing general life stress. However, interventions that explicitly target mental representations of cancer may be needed to modify perceptions of the disease. Copyright © 2011 John Wiley & Sons, Ltd.
Tryptophan side chain conformers monitored by NMR and time‐resolved fluorescence spectroscopies
Authors: Julien Olivier , Wang Guoli , Jonckheer Abel , Engelborghs Yves , Sykes Brian D.
Published: September 2011

We have inserted a tryptophan (F77W) in the core of the regulatory domain of cardiac troponin C (cNTnC), and previously determined the structure of this mutant with and without the cosolvent trifluoroethanol (TFE). Interestingly, the orientations of the indole side chain of the Trp are in opposite directions in the two structures (Julien et al., Protein Sci 2009; 18:1165–1174). Fluorescence decay experiments for single Trp‐containing proteins often show several lifetimes, which have been interpreted as reflecting conformational heterogeneity of the Trp side chain resulting from different rotamers. To test this interpretation, we monitored the effect of TFE on wild type, F77W and F77W‐V82A calcium‐saturated cNTnC using 2D 13C‐HSQC NMR and time‐correlated single photon counting fluorescence spectroscopies. The time dependence of the Trp fluorescence decay was fit with three lifetimes. Addition of TFE caused a gradual, but limited decrease of the lifetimes due to dynamic quenching. For F77W cNTnC, the amplitude fractions of the lifetimes also changed upon addition of TFE—the long lifetime increased from 13 to 29%, while the middle lifetime decreased from 63 to 50% and the short lifetime remained relatively unchanged. For F77W‐V82A cNTnC, comparable NMR changes are observed, confirming the switch in rotamer conformation, but only much smaller changes in fluorescence decay parameters were detected. These data indicate that the balance between the rotamer states can be changed without changing the lifetime amplitude fractions appreciably, and suggest that the environment(s) of the indole ring, responsible for the different lifetimes, can result from factors other than the intrinsic rotamer state of the tryptophan. Proteins 2012; © 2011 Wiley Periodicals, Inc.
Effects on Raman spectra of functionalisation of single walled carbon nanotubes by nitric acid
Authors: Mases M. , Noël M. , Mercier G. , Dossot M. , Vigolo B. , Mamane V. , Fort Y. , Soldatov A. V. , McRae E.
Published: September 2011

In the ultimate aim of grafting a fluorescent group on carbon nanotubes (CNTs) using COOH functions as anchoring groups, it was realised that optimisation of the carboxylation step of the CNTs was essential in the overall process. To reach this goal, three different treatment times with refluxed nitric acid have been tested: 2, 5 and 10 h. Electron microscopy has allowed evaluating the microstructure changes and the chemical composition on a local level. Raman spectroscopy has revealed a number of interesting evolutions especially in the D and G bands spectral region. It seems that residual nitric acid molecules may partially transfer charge to CNTs, giving rise to a doping effect, as is well known in graphite intercalation compounds.
Electronic state of polyaniline deposited on carbon nanotube or ordered mesoporous carbon templates
Authors: Bulusheva L. G. , Fedorovskaya E. O. , Okotrub A. V. , Maximovskiy E. A. , Vyalikh D. V. , Chen Xiaohong , Song Huaihe
Published: September 2011

Polyaniline (PANI) has been deposited on a carbon template by chemical oxidation of aniline chloride in acidic aqueous medium using sodium persulfate as oxidant. Two kinds of templates were used: array of aligned multiwall carbon nanotubes (CNTs) grown on silicon substrate and ordered mesoporous carbon (OMC) material. Electronic structure of composites was examined using near‐edge X‐ray absorption spectroscopy and X‐ray photoelectron spectroscopy. Analysis of the spectra showed that PANI developed on the CNT surface is mainly protonated while it contains a marked amount of imine (N) nitrogen when deposited into the porous of OMC. Testing of electrochemical cell indicated enhancement of performance of composite electrodes as compared with unsupported PANI.

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XPS N 1s spectra of composites of PANI with OMC material (PANI/OMC) and aligned multiwall CNTs (PANI/CNT).
An evidential approach to non‐inferiority clinical trials
Authors: Wang Sue‐Jane , Blume Jeffrey D.
Published: September 2011

We present likelihood methods for defining the non‐inferiority margin and measuring the strength of evidence in non‐inferiority trials using the ‘fixed‐margin’ framework. Likelihood methods are used to (1) evaluate and combine the evidence from historical trials to define the non‐inferiority margin, (2) assess and report the smallest non‐inferiority margin supported by the data, and (3) assess potential violations of the constancy assumption. Data from six aspirin‐controlled trials for acute coronary syndrome and data from an active‐controlled trial for acute coronary syndrome, Organisation to Assess Strategies for Ischemic Syndromes (OASIS‐2) trial, are used for illustration. The likelihood framework offers important theoretical and practical advantages when measuring the strength of evidence in non‐inferiority trials. Besides eliminating the influence of sample spaces and prior probabilities on the ‘strength of evidence in the data’, the likelihood approach maintains good frequentist properties. Violations of the constancy assumption can be assessed in the likelihood framework when it is appropriate to assume a unifying regression model for trial data and a constant control effect including a control rate parameter and a placebo rate parameter across historical placebo controlled trials and the non‐inferiority trial. In situations where the statistical non‐inferiority margin is data driven, lower likelihood support interval limits provide plausibly conservative candidate margins. Copyright © 2011 John Wiley & Sons, Ltd.
A New Ordering Method of Basic Events in Fault Tree Analysis
Authors: Huang Hong‐Zhong , Zhang Hua , Li Yanfeng
Published: September 2011

The ordering of basic events is critical to fault tree analysis on the basis of binary decision diagrams (BDDs). Many attempts have been made to seek an efficient ordering result with the aim of reducing the complexity of BDD. In this article, a new ordering method, namely, priority ordering method, is proposed. The new method takes into account not only the effects of the layers of fault tree but also the repeated events, the neighboring events, and the number of events under the same gate. According to these four effects, the priorities that sort the basic events of the fault tree are defined. The new method inherits the merits of structure‐based and weight‐based methods. It is able to evaluate the basic events on the basis of the structure‐based method and the size of the subtree on the basis of the weighted‐based method. Demonstrated by the examples, the proposed priority ordering method is superior to the existing ordering methods in terms of reducing the nodes in the BDD and improving the efficiency in transforming a fault tree to a BDD. Copyright © 2011 John Wiley & Sons, Ltd.
A method for fast encoder‐free mapping in unstructured environments
Authors: Milstein Adam , McGill Matthew , Wiley Timothy , Salleh Rudino , Sammut Claude
Published: September 2011

The primary purpose of rescue robots is to locate victims within a disaster environment, either to report their position or to deliver aid. Although there exist several solutions for mapping and localizing a robot in an unknown environment, they often require an estimate of the robot's motion. In a disaster site, a robot might not have effective motion encoders, either because of the discontinuous nature of the terrain or because the robot's locomotion devices do not remain in constant contact with the ground. We have developed an algorithm for tracking the position of a robot in a disaster environment and generating a map that functions in real time. Our solution is based on a range finder device and is robust to temporary errors in the range scan. By aligning each scan to an occupancy grid of prior scan data, we can find the robot's position more accurately than current techniques that align only to the previous scan. The accurate position tracking allows us to more efficiently implement a solution to the mapping problem. In addition, our solution can track the position of the robot and generate a map based on three‐dimensional scan data, instead of requiring that the range sensor be fixed in a level plane. © 2011 Wiley Periodicals, Inc.
Perceived Neighborhood Social Resources as Determinants of Prosocial Behavior in Early Adolescence
Authors: Lenzi Michela , Vieno Alessio , Perkins Douglas D. , Pastore Massimiliano , Santinello Massimo , Mazzardis Sonia
Published: September 2011

The present study aims to develop an integrative model that links neighborhood behavioral opportunities and social resources (neighborhood cohesion, neighborhood friendship and neighborhood attachment) to prosocial (sharing, helping, empathic) behavior in early adolescence, taking into account the potential mediating role of perceived support of friends. Path analysis was used to test the proposed theoretical model in a sample of 1,145 Italian early adolescents (6th through 8th graders). More perceived opportunities and social resources in the neighborhood are related to higher levels of adolescent prosocial behavior, and this relationship is partially mediated by perceived social support from friends. The results offer promising implications for future research and intervention programs that aim to modify social systems to improve child and adolescent social competencies.
Hippocampal atrophy as a surrogate of neuronal involvement in Fabry disease
Authors: Fellgiebel Andreas , Wolf Dominik O. , Kolodny Edwin , Müller Matthias J.
Published: September 2011

Cerebral micro‐ and macro‐vasculopathy have been described in Fabry disease (FD). Neuronal globotriaosylceramide accumulation in selective cortical and brain stem areas including the hippocampus has been reported by autopsy studies in FD, but clinical surrogates as well as the clinical relevance of these findings have not been investigated so far. We measured the hippocampus volumes in a group of clinically affected patients with FD and correlated the findings with the cognitive performance of the patients. Hippocampal volumes were determined manually on T1‐weighted MR‐images of 25 FD patients (age 36.5 ± 11.0 years) and 20 age‐matched controls. Additionally, individual white matter (WM) and gray matter (GM) volumes were measured using brain segmentation analyses. After controlling for age, white matter lesion (WML) volume, and WM/GM‐volumes hippocampal volumes were significantly decreased in FD. These findings were substantially more pronounced in a subgroup of men with FD. WM and WM/GM volumes, and memory function did not significantly differ between patients and controls. In patients with FD hippocampal volumes were neither significantly correlated to WML volume nor to WM or WM/GM volumes. Hippocampus atrophy was not driven by the WML or other brain tissue atrophy and seems to correlate with the neuronal involvement in FD. In this young to middle‐aged Fabry cohort the hippocampus degeneration was functionally compensated without memory impairment. Longitudinal studies are needed to determine whether this degenerative component in FD will progress and, in concert with the individual WML‐load, predict subsequent cognitive decline.
A programmed schedule of oocyte retrieval using mild ovarian stimulation (clomiphene citrate and recombinant follicle‐stimulating hormone)
Authors: Nakagawa Koji , Nishi Yayoi , Sugiyama Rie , Jyuen Hiroyasu , Takahashi Chie , Ojiro Yuko , Kuribayashi Yasushi , Sugiyama Rikikazu
Published: September 2011

Purpose

The purpose was to establish a mild ovarian stimulation protocol that would help assisted reproductive technology (ART) units to avoid scheduling on weekends.

Methods

This protocol directed patients to take 50 mg/day of clomiphene citrate between days 3 and 7 of the menstrual cycle: 225 IU of recombinant follicle‐stimulating hormone (rec‐FSH) were administered on days 3, 5 and 7; human chorionic gonadotropin (hCG) was administered on day 9; and, oocyte pick‐up (OPU) was planned for day 11. From October 2008 through October 2009, 514 women underwent ART treatment with mild stimulation at the Sugiyama Clinic, and we evaluated whether OPU was accomplished on the planned day.

Results

Of all the treatment cycles, 419 (81.5%) underwent OPU on day 11 (scheduled group). Additional rec‐FSH administration was needed in 83 cycles, in which case OPU was performed on day 12 or later. In 12 cycles, OPU was canceled. The unscheduled group (n = 95) consisted of delayed OPU cycles and canceled cycles. Of all treatment cycles, 332 cycles in the scheduled group and 68 cycles in the unscheduled group underwent embryo transfer, with 81 and 16, respectively, resulting in pregnancies.

Conclusions

Using this protocol, OPU was performed on the scheduled day in about 80% of the cycles. Most weekend scheduling of OPU can be avoided using this mild stimulation.
Streaming-potential phenomena in the thin-Debye-layer limit. Part 1. General theory
Authors: Yariv Ehud , Schnitzer Ory , Frankel Itzchak
Published: September 2011

Electrokinetic streaming-potential phenomena are driven by imposed relative motion between liquid electrolytes and charged solids. Owing to non-uniform convective ‘surface’ current within the Debye layer Ohmic currents from the electro-neutral bulk are required to ensure charge conservation thereby inducing a bulk electric field. This, in turn, results in electro-viscous drag enhancement. The appropriate modelling of these phenomena in the limit of thin Debye layers $\delta \ensuremath{\rightarrow} 0$ ($\delta $ denoting the dimensionless Debye thickness) has been a matter of ongoing controversy apparently settled by Cox’s seminal analysis (J. Fluid Mech., vol. 338, 1997, p. 1). This analysis predicts electro-viscous forces that scale as ${\delta }^{4} $ resulting from the perturbation of the original Stokes flow with the Maxwell-stress contribution only appearing at higher orders. Using scaling analysis we clarify the distinction between the normalizations pertinent to field- and motion-driven electrokinetic phenomena, respectively. In the latter class we demonstrate that the product of the Hartmann & Péclet numbers is $O({\delta }^{\ensuremath{-} 2} )$ contrary to Cox (1997) where both parameters are assumed $O(1)$. We focus on the case where motion-induced fields are comparable to the thermal scale and accordingly present a singular-perturbation analysis for the limit where the Hartmann number is $O(1)$ and the Péclet number is $O({\delta }^{\ensuremath{-} 2} )$. Electric-current matching between the Debye layer and the electro-neutral bulk provides an inhomogeneous Neumann condition governing the electric field in the latter. This field, in turn, results in a velocity perturbation generated by a Smoluchowski-type slip condition. Owing to the dominant convection, the present analysis yields an asymptotic structure considerably simpler than that of Cox (1997): the electro-viscous effect now already appears at $O({\delta }^{2} )$ and is contributed by both Maxwell and viscous stresses. The present paradigm is illustrated for the prototypic problem of a sphere sedimenting in an unbounded fluid domain with the resulting drag correction differing from that calculated by Cox (1997). Independently of current matching, salt-flux matching between the Debye layer and the bulk domain needs also to be satisfied. This subtle point has apparently gone unnoticed in the literature, perhaps because it is trivially satisfied in field-driven problems. In the present limit this requirement seems incompatible with the uniform salt distribution in the convection-dominated bulk domain. This paradox is resolved by identifying the dual singularity associated with the limit $\delta \ensuremath{\rightarrow} 0$ in motion-driven problems resulting in a diffusive layer of $O({\delta }^{2/ 3} )$ thickness beyond the familiar $O(\delta )$-wide Debye layer.
Retirement Lost?
Authors: McDonald Lynn , Donahue Peter
Published: September 2011

Cet article soulève la question de savoir si la retraite, comme nous la connaissons et comprenons actuellement au Canada, est perdue. Grâce à un examen sélectif, nous examinons la recherche sur la retraite selon la durée de la retraite, de nouveaux types de retraite, les évolutions théoriques possibles, les moments de transition vers la retraite, et la vie des retraités, y inclus la qualité ou le manque de pensions. En conséquence, nous proposons que la retraite est soumise a des modifications sur la base de plusieurs tendances qui ont commencé avant le ralentissement économique de 2008. Les données semblent indiquer l’émergence d’un type différent de la retraite, dans la mesure où la vision collective canadienne de la retraite n’est pas perdue, malgré la crise économique sur les marchés mondiaux.