bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth defects in a PZNT93/7 crystal prepared by directional solidification
Authors: Jin Min , Xu Jiayue , Li Xinhua , Shen Hui , He Qingbo 
Published: May 2008

AbstractNovel relaxor ferroelectric crystal 0.93Pb(Zn1/3Nb2/3)O3‐0.07PbTiO3 (PZNT93/7) with dimensions about Ø40× 70 mm3 was obtained by directional solidification technique. The growth defects of the crystal were investigated. Rocking curve analysis revealed the crystalline quality of PZNT93/7 crystal was not perfect and the FWHM value was measured to be about 0.7°. Some pits and oxide particles in micro‐size were formed in the crystal due to the growth conditions. A series of growth steps parallel to (001) face were observed which were attributed to the growth behavior. Moreover, it was found the average chemical composition of the crystal was deviated slightly to the stoichiometric value of PZNT93/7. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modulation of murine dendritic cell function by adenine nucleotides and adenosine: Involvement of the A2B receptor
Authors: Addi Abduelhakem Ben , Lefort Anne , Hua Xiaoyang , Libert Frédérick , Communi Didier , Ledent Catherine , Macours Pascale , Tilley Stephen L. , Boeynaems Jean‐Marie , Robaye Bernard 
Published: May 2008

AbstractAdenosine triphosphate has previously been shown to induce semi‐mature human monocyte‐derived dendritic cells (DC). These are characterized by the up‐regulation of co‐stimulatory molecules, the inhibition of IL‐12 and the up‐regulation of some genes involved in immune tolerance, such as thrombospondin‐1 and indoleamine 2,3‐dioxygenase. The actions of adenosine triphosphate are mediated by the P2Y11 receptor; since there is no functional P2Y11 gene in the murine genome, we investigated the action of adenine nucleotides on murine DC. Adenosine 5′‐(3‐thiotriphosphate) and adenosine inhibited the production of IL‐12p70 by bone marrow‐derived DC (BMDC). These inhibitions were relieved by 8‐p‐sulfophenyltheophylline, an adenosine receptor antagonist. The use of selective ligands and A BMDC indicated the involvement of the A2B receptor. A microarray experiment, confirmed by quantitative PCR, showed that, in presence of LPS, 5′‐(N‐ethylcarboxamido) adenosine (NECA, the most potent A2B receptor agonist) regulated the expression of several genes: arginase I and II, thrombospondin‐1 and vascular endothelial growth factor were up‐regulated whereas CCL2 and CCL12 were down‐regulated. We further showed that NECA, in combination with LPS, increased the arginase I enzymatic activity. In conclusion, the described actions of adenine nucleotides on BMDC are mediated by their degradation product, adenosine, acting on the A2B receptor, and will possibly lead to an impairment of Th1 response or tolerance.
Circumvention of regulatory CD4+ T cell activity during cross‐priming strongly enhances T cell‐mediated immunity
Authors: Heit Antje , Gebhardt Friedemann , Lahl Katharina , Neuenhahn Michael , Schmitz Frank , Anderl Florian , Wagner Hermann , Sparwasser Tim , Busch Dirk H. , Kastenmüller Kathrin 
Published: May 2008

AbstractImmunization with purified antigens is a safe and practical vaccination strategy but is generally unable to induce sustained CD8+ T cell‐mediated protection against intracellular pathogens. Most efforts to improve the CD8+ T cell immunogenicity of these vaccines have focused on co‐administration of adjuvant to support cross‐presentation and dendritic cell maturation. In addition, it has been shown that CD4+ T cell help during the priming phase contributes to the generation of protective CD8+ memory T cells. In this report we demonstrate that the depletion of CD4+ T cells paradoxically enhances long‐lasting CD8‐mediated protective immunity upon protein vaccination. Functional and genetic in vivo inactivation experiments attribute this enhancement primarily to MHC class II‐restricted CD4+ regulatory T cells (Treg), which appear to physiologically suppress the differentiation process towards long‐living effector memory T cells. Since, in functional terms, this suppression by Treg largely exceeds the positive effects of conventional CD4+ T cell help, even the absence of all CD4+ T cells or lack of MHC class II‐mediated interactions on priming dendritic cells result in enhanced CD8+ T cell immunogenicity. These findings have important implications for the improvement of vaccines against intracellular pathogens or tumors, especially in patients with highly active Treg.Supporting Information for this article is available at www.wiley‐vch.de/contents/jc_2040/2008/37966_s.pdf
Redundant role for Zap70 in B cell development and activation
Authors: Fallah‐Arani Farnaz , Schweighoffer Edina , Vanes Lesley , Tybulewicz Victor L. J. 
Published: May 2008

AbstractExpression of the Syk family tyrosine kinase Zap70 is strongly correlated with poor clinical outcome in chronic lymphocytic leukemia, the most common human leukemia characterized by B cell accumulation. The expression of Zap70 may reflect the specific cell of origin of the tumor or may contribute to pathology. Thus, the normal role of Zap70 in B cell physiology is of great interest. While initial studies reported that Zap70 expression in the mouse was limited to T and NK cells, more recent work has shown expression in early B cell progenitors and in splenic B cells, suggesting that the kinase may play a role in the development or activation of B cells. In this study, we show that Zap70 is expressed in all developing subsets of B cells as well as in recirculating B cells, marginal zone B cells and peritoneal B1 cells. Analysis of Zap70‐deficient mice shows no unique role for Zap70 in either the development of B cells or in their in vitro and in vivo activation. However, we show that Zap70 can rescue the defective positive selection of immature B cells into the recirculating pool in Syk‐deficient mice, demonstrating functional redundancy between these two kinases.
Role of Ets‐1 phosphorylation in the effector function of Th cells
Authors: Grenningloh Roland , Miaw Shi‐Chuen , Moisan Jacques , Graves Barbara J. , Ho I‐Cheng 
Published: May 2008

AbstractThe transcription factor Ets‐1 critically regulates differentiation and function of T helper (Th) cells. In vitro studies have demonstrated that DNA binding and transcriptional activity of Ets‐1 are regulated by phosphorylation. Depending on the site of phosphorylation, Ets‐1 function can either be increased or inhibited. In addition, a splice variant lacking several inhibitory phosphorylation sites has been identified, raising the possibility that this splice variant may function differently from the full‐length Ets‐1. However, it is unclear how the activating and inhibitory phosphorylation events of Ets‐1 are coordinated during Th cell activation. Furthermore, the biological consequences of Ets‐1 phosphorylation and alternative splicing in regulating the function of Th cells are unknown. We report here that both activating and inhibitory phosphorylation events of Ets‐1 occur simultaneously and independently of each other during Th cell activation. We further demonstrate that the effect of Ets‐1 phosphorylation is very modest and that full‐length Ets‐1 and its splice variant are functionally interchangeable in the regulation of cytokine production in Th cells.Supporting Information for this article is available at www.wiley‐vch.de/contents/jc_2040/2008/38112_s.pdf
Immunological mechanisms and clinical implications of regulatory T cell deficiency in a systemic autoimmune disorder: Roles of IL‐2 versus IL‐15
Authors: Yang Cui‐Hong , Tian Lina , Ling Guang‐Sheng , Trendell‐Smith Nigel J. , Ma Liang , Lo Chi‐Kin , Stott David I. , Liew Foo Y. , Huang Fang‐Ping 
Published: May 2008

AbstractRegulatory T cell deficiency is evident in patients with lupus, but the casual relationship and underlying mechanism leading to Treg deficiency are unclear. We analyzed the Treg profile, induction and functions of Treg in a lupus mouse model. A characteristic age‐dependent biphasic change of Treg frequency was observed in the MRL/lpr mice, which developed a spontaneous lupus‐like disease. After an early increase, Treg frequency in the peripheral lymphoid organs rapidly declined with age. Functionally, Treg from both young and old MRL/lpr mice were fully competent in suppressing the wild‐type MRL/+ T effector cell (Teff) responses. Adoptive transfer of MRL/+ Treg markedly suppressed clinical disease in the MRL/lpr mice. We demonstrated that the reduced Treg frequency was a result of insufficient peripheral Treg expansion due to defective MRL/lpr Teff in IL‐2 production, and the associated defects in dendritic cells, which could be fully restored by exogenous IL‐2. In the absence of IL‐2, MRL/lpr Teff but not MRL/lpr Treg were highly responsive to IL‐15 and could expand rapidly due to enhanced IL‐15R expression and IL‐15 synthesis. These findings thus provide a clear causal relationship and immunological mechanism underlying Treg deficiency and systemic autoimmunity.Supporting Information for this article is available at www.wiley‐vch.de/contents/jc_2040/2008/38190_s.pdf
Syntheses, Structures and Reactivities of [CpTc(CO)3X]+ and [CpRe(CO)3X]+
Authors: Zobi Fabio , Spingler Bernhard , Alberto Roger 
Published: May 2008

AbstractWe have synthesized the [Cp*MIII(CO)3Br]+ complexes (M = Re, 99Tc) and studied their basic chemistry in water and in organic solvents in order to understand if these complexes could be synthons for the preparation of new Re‐ and 99Tc‐based cyclopentadienyl cores for (radio)pharmaceutical applications. The [Cp*MIII(CO)3Br]Br [M = Re (1), 99Tc (1a)] complexes were obtained in nearly quantitative yield from the reaction of the corresponding [Cp*MI(CO)3] with Br2 in cold toluene. Compounds 1 and 1a are photo‐ and thermally unstable and undergo rapid, bromide concentration‐dependent redox reactions at room temperature generating the stable [Cp*MIII(CO)3Br][(CO)3MI(μ‐Br)3MI(CO)3] [M = Re (2), 99Tc (2a)] species as main products. Reaction of 1 with AgSbF6 gives rise to the redox‐stable complex [Cp*ReIII(CO)3Br]SbF6 (3). In water, 1 and 1a produces a mixture of cis/trans‐[Cp*MIIIBr2(CO)2] isomers [M = Re (cis/trans‐4), 99Tc (cis/trans‐4a)] via CO release. In methanol, 3 reacts with the solvent to generate the methoxycarbonyl complex trans‐[Cp*ReIII(CO)2Br(COOCH3)] (5). Compound 5 is stable under basic conditions. In acidic media it is converted into [Cp*ReI(CO)3] as the major product. Kinetic studies with 13C labelled formic acid indicate that formic acid, generated from rapid hydrolysis of methyl formate released from 5, is the reducing agent and the source of CO. Reaction of 1 with 3‐fluorobenzyl alcohol (3‐FBA), chosen as a simple model of fluorouracil, gives the corresponding alkoxycarbonyl complex [Cp*ReIII(CO)2Br(COOCH2–C6H4F)] (7). Under acidic conditions 7 rapidly releases 3‐FBA to give [Cp*ReI(CO)3]. Compounds 2, 2a, cis‐4, trans‐4a and 5 were structurally characterized.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis and Crystal Structure Investigations of Trivalent Rare Earth (Y3+, Nd3+, Er3+) Thienyl‐Substituted Methoxides (Eur. J. Inorg. Chem. 15/2008)
Authors: Veith Michael , Belot Céline , Guyard Laurent , Huch Volker , Knorr Michael , Zimmer Michael 
Published: May 2008

AbstractThe cover picture shows the X‐ray crystal structure of {Nd[OC(C4H3S)3]3(thf)3}·thf, a new neodymium thienylmethoxide. The structure determination of this compound reveals a monomer with an approximately octahedral geometry around the neodymium atom: this metal centre is surrounded by three tris(2‐thienyl)methoxido ligands and three tetrahydrofuran molecules in a facial arrangement. Details are discussed in the article by M. Veith et al. on p. 2397 ff.
Selective Reduction of Carbonyl Amides: Toward the First Unsymmetrical Bischelating N‐Substituted 1,2‐Diamino‐4,5‐di­amidobenzene
Authors: Seillan Claire , Braunstein Pierre , Siri Olivier 
Published: May 2008

AbstractSelective reduction of carbonyl amides from key tetraamido intermediate 12 afforded an unprecedented N‐substituted 1,2‐diamino‐4,5‐diamidobenzene (13) and/or the firstmember (14) of a new family of unsymmetrical 12π‐electron quinonediimines. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Twin Triptycyl Spinning Tops: A Simple Case of Molecular Gearing with Dynamic C2 Symmetry
Authors: Nikitin Kirill , Müller‐Bunz Helge , Ortin Yannick , Risse Wilhelm , McGlinchey Michael J. 
Published: May 2008

AbstractLithiation and subsequent oxidation of the recently described prototype molecular paddlewheel 9‐(2‐indenyl)triptycene (1) leads to the racemic dimer 2,2′‐bis(9‐triptycyl)‐1,1′‐biindenyl (4). In the solid state this very congested molecule adopts a conformation in which the two triptycenyl paddlewheel fragments are attached to the C2‐symmetric biindenyl core. However, the orientation of the triptycene blades, dictated by their size and shape, is gear‐like and breaks the nascent C2‐symmetry of the whole molecule. Nevertheless, effective C2‐symmetry is restored in solution when the triptycene paddlewheels, although apparently tightly interlocked, undergo rapid contra‐rotation on the NMR time‐scale. The analogous reaction of (2‐phenylindenyl)lithium (6), likewise yields racemic (RR/SS) 2,2′‐diphenyl‐1,1′‐biindenyl(7). Interestingly, although the treatment of 6 with a CuII salt leads to both rac‐7 and its diastereomer meso‐7, the reaction of 6 and 2‐phenylindenyl bromide furnishes selectively rac‐7. Overall, these data suggest that the oxidative dimerisation to yield racemic products occurs through a nucleophilic substitution mechanism. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Evaluation of a dynamic multi‐class sediment transport model in a catchment under soil‐conservation agriculture
Authors: Fiener Peter , Govers Gerard , Oost Kristof Van 
Published: May 2008

AbstractSoil erosion models are essential tools for the successful implementation of effective and adapted soil conservation measures on agricultural land. Therefore, models are needed that predict sediment delivery and quality, give a good spatial representation of erosion and deposition and allow us to account for various soil conservation measures.Here, we evaluate how well a modified version of the spatially distributed multi‐class sediment transport model (MCST) simulates the effectiveness of control measures for different event sizes. We use 8 year runoff and sediment delivery data from two small agricultural watersheds (0·7 and 3·7 ha) under optimized soil conservation. The modified MCST model successfully simulates surface runoff and sediment delivery from both watersheds; one of which was dominated by sheet and the other was partly affected by rill erosion. Moreover, first results of modelling enrichment of clay in sediment delivery are promising, showing the potential of MCST to model sediment enrichment and nutrient transport.In general, our results and those of an earlier modelling exercise in the Belgian Loess Belt indicate the potential of the MCST model to evaluate soil erosion and deposition under different agricultural land uses. As the model explicitly takes into account the dominant effects of soil‐conservation agriculture, it should be successfully applicable for soil‐conservation planning/evaluation in other environments. Copyright © 2008 John Wiley & Sons, Ltd.
Bed morphology and generation of step–pool channels
Authors: Weichert Roman B. , Bezzola Gian Reto , Minor Hans‐Erwin 
Published: May 2008

AbstractFlume experiments have been carried out to study the formation processes and the bed morphology of step–pool channels. From the experiments different step types and step configurations could be distinguished depending on the stream power. These step types can be seen as an image of the generation mechanisms of step–pool systems. These results suggest that the bed roughness geometry develops towards a condition that provides the maximum possible bed stability for a given grain size distribution. In contrast to a variety of other studies, antidunes did not contribute to the generation of the step structures. However, the data of the presented study fits well into the region of antidune formation proposed by Kennedy for sand‐bed rivers. This observation points out that step–pool field‐data located in the Kennedy region do not inevitably prove that antidunes played a role in step development. It is rather proposed that in Kennedy's region of antidune formation there exist hydraulic conditions where the flow resistance is maximized. It is suggested that such maximum flow resistance is associated with an optimal distance between the bedforms and their height, independently of whether these are antidunes in sand‐ and gravel‐bed rivers or step–pool units in boulder‐bed streams. The considerations of the Kennedy region of antidune formation and the analysis of planform step types depending on stream power both suggest that steep channels have a potential for self‐stabilization by modifying the step–pool structure towards a geometry that provides maximum flow resistance and maximum bed stability. Copyright © 2008 John Wiley & Sons, Ltd.
Correlates of intrusion and avoidance as stress response symptoms in family carers of patients suffering from dementia
Authors: Ulstein Ingun , Wyller Torgeir Bruun , Engedal Knut 
Published: May 2008

AbstractAimsTo explore intrusion and avoidance in family carers of dementia patients.MethodWe studied 196 family carers of 196 home‐dwelling dementia patients. Carers were assessed by the Impact of Events Scale (IES), the Geriatric Depression Scale (GDS), the State Trait Anxiety Inventory (STAI) and the Distress scale of the Neuropsychiatric Inventory (NPI‐D), and patients with the Mini Mental State Examination (MMSE), the Disability Assessment for Dementia (DAD), and the Neuropsychiatric Inventory (NPI).ResultsTwenty carers (10%) scored above 19 on the intrusion and avoidance subscales of the IES, whereas 90 (47%) scored above 8 on both subscales. This moderate to high stress response was independently explained by being a spouse (OR 3.74 (95% CI 1.81–7.74)), high scores on GDS (OR 1.12 (95% CI 1.06–1.18) per unit increase) and high score on NPI‐D (OR 1.05 (95% CI 1.01–1.09) per unit increase).ConclusionsSpouses and other family carers having daily contact with patients with dementia experience moderate to high levels of intrusion and avoidance. These symptoms are associated with symptoms of anxiety, distress and depression and should be taken into account when tailoring interventions for carers. Copyright © 2008 John Wiley & Sons, Ltd.
Significant effect of APOE epsilon 4 genotype on the risk of dementia in Alzheimer's disease and mortality in persons with Down Syndrome
Authors: Prasher V. P. , Sajith S. G. , Rees S. D. , Patel A. , Tewari S. , Schupf N. , Zigman W. B. 
Published: May 2008

AbstractObjectiveVirtually all adults with Down syndrome (DS) have neuropathological manifestations of Dementia in Alzheimer's disease (DAD) but not all develop clinical psychopathology. The effect of allelic variants of Apolipoprotein (APOE) gene in development and progression of DAD and mortality in persons with DS is examined.MethodsRecruited participants with DS underwent two to 14 sequential assessments over a follow up period of 6 years on average and their APOE genotype determined. Dementia statuswas confirmed as recommended by the Working Group for the Establishment of Criteria forthe Diagnosis of Dementia in Individuals with Intellectual Disability.ResultsAPOE genotype results were available for 252 individuals. Participants with APOE ε4 allele had significantly higher risk of developing DAD (HR = 1.8, 95% CI: 1.12–2.79), had an earlier onset of DAD (55.0 vs 57.0 years; p = 0.0027) and a more rapid progression to death compared with participants with ε3 allele (4.2 years vs. 5.4 years, respectively, p = 0.048). In non‐demented persons with DS, ε4 allele was associated with earlier death by 17 years (mean survival age, 55.7 vs. 72.7 years; HR = 5.9, 95% CI: 1.7–21.3).ConclusionsThis study highlights the relationship of APOE genotype to morbidity and mortality in persons with DS which has important clinical implications. We recommend screening for APOE genotype in persons with DS to identify those at risk of DAD and premature death. Further research is required to investigate the underlying reasons for the early mortality in non‐demented DS persons with an ε4 allele. Copyright © 2008 John Wiley & Sons, Ltd.
Automatic fMRI‐guided MEG multidipole localization for visual responses
Authors: Auranen Toni , Nummenmaa Aapo , Vanni Simo , Vehtari Aki , Hämäläinen Matti S. , Lampinen Jouko , Jääskeläinen Iiro P. 
Published: May 2008

AbstractPreviously, we introduced the use of individual cortical location and orientation constraints in the spatiotemporal Bayesian dipole analysis setting proposed by Jun et al. ([2005]; Neuroimage 28:84–98). However, the model's performance was limited by slow convergence and multimodality of the numerically estimated posterior distribution. In this paper, we present an intuitive way to exploit functional magnetic resonance imaging (fMRI) data in the Markov chain Monte Carlo sampling ‐based inverse estimation of magnetoencephalographic (MEG) data. We used simulated MEG and fMRI data to show that the convergence and localization accuracy of the method is significantly improved with the help of fMRI‐guided proposal distributions. We further demonstrate, using an identical visual stimulation paradigm in both fMRI and MEG, the usefulness of this type of automated approach when investigating activation patterns with several spatially close and temporally overlapping sources. Theoretically, the MEG inverse estimates are not biased and should yield the same results even without fMRI information, however, in practice the multimodality of the posterior distribution causes problems due to the limited mixing properties of the sampler. On this account, the algorithm acts perhaps more as a stochastic optimizer than enables a full Bayesian posterior analysis. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.
Differential cerebellar and cortical involvement according to various attentional load: Role of educational level
Authors: Bonnet Melissa C. , Dilharreguy Bixente , Allard Michele , Deloire Mathilde S.A. , Petry Klaus G. , Brochet Bruno 
Published: May 2008

AbstractRecent imaging studies have evidenced various cerebral patterns dependent on educational level during cognitive tasks in neurodegenerative diseases. Determining relationships between educational status and cerebral activation during cognitive demands in physiological conditions may help to better understand the role of education on cognitive efficacy and functional reorganisation in pathological conditions. We proposed to analyse by functional MRI (fMRI) the relationship between educational status and cerebral activation during various attentional requests in healthy young adults. Twenty healthy young adults completed four successive conditions of a Go/No‐go test of increasing complexity under fMRI. An effect of education was observed on attentional performances. Both in‐scanner response times and cerebral activation increased during the Go/No‐go paradigm. Healthy subjects with higher education exhibited higher activity in cerebellum and lower activity in medial prefrontal and inferior parietal regions compared with the healthy subjects with lower educational levels while performing the conditions of Go/No‐go task. Our data evidence the influence of education on automatized strategies in healthy adults by modulating a functional balance of activation between cerebral cortex and cerebellar regions during attentional processes. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.