bluuebunny/crossref_metadata_2025 huggingface dataset:
RAS signaling dysregulation in human embryonal Rhabdomyosarcoma
Authors: Martinelli Simone , McDowell Heather P. , Vigne Silvia Delle , Kokai George , Uccini Stefania , Tartaglia Marco , Dominici Carlo
Published: August 2009

Rhabdomyosarcoma (RMS) is a common childhood solid tumor, resulting from dysregulation of the skeletal myogenesis program. Two major histological subtypes occur in childhood RMS, embryonal and alveolar. While chromosomal rearrangements account for the majority of alveolar tumors, the genetic defects underlying the pathogenesis of embryonal RMS remain largely undetermined. A few studies performed on small series of embryonal tumors suggest that dysregulation of RAS function may be relevant to disease pathogenesis. To explore further the biological and clinical relevance of mutations with perturbing consequences on RAS signaling in embryonal RMS, we investigated the prevalence of PTPN11, HRAS, KRAS, NRAS, BRAF, MEK1, and MEK2 mutations in a relatively large cohort of primary tumors. While HRAS and KRAS were found to be rarely mutated, we identified somatic NRAS lesions in 20% of cases. All mutations were missense and affected codon 61, with the introduction of a positive charged amino acid residue representing the most common event. PTPN11 was found mutated in one tumor specimen, confirming that somatic defects in this gene are relatively uncommon in RMS, while no mutation was observed in BRAF and MEK genes. Although no clear association of mutations with any clinical variable was observed, comparison of the outcome between mutation‐positive and mutation‐negative cases indicated a trend for a higher percentage of patients exhibiting a better outcome in the former. Our findings provide evidence that dysregulation of RAS signaling is a major event contributing to embryonal RMS pathogenesis. © 2009 Wiley‐Liss, Inc.
Protocadherin PCDH10, involved in tumor progression, is a frequent and early target of promoter hypermethylation in cervical cancer
Authors: Narayan Gopeshwar , Scotto Luigi , Neelakantan Vijayalakshmi , Kottoor Sherine H. , Wong Ada Ho Yan , Loke Shee‐Loong , Mansukhani Mahesh , Pothuri Bhavana , Wright Jason D. , Kaufmann Andreas M. , Schneider Achim , Arias‐Pulido Hugo , Tao Qian , Murty Vundavalli V.
Published: August 2009

Cervical cancer (CC) is the second most common cancer in women. Currently, no tractable molecular‐based therapeutic targets exist for patients with invasive CC and no predictive markers of risk assessment for progression of precancerous lesions are identified. New molecular insights into CC pathogenesis are urgently needed. Towards this goal, we first determined the copy number alterations of chromosome 4 and then examined the role of PCDH10 mapped to 4q28 as a candidate tumor suppressor gene. We identified monosomy 4 in 47% of 81 invasive CC studied by SNP array and found that 91% of 130 invasive CC harboring methylation in the promoter region of the PCDH10 gene. We then showed that aberrant promoter hypermethylation of PCDH10 is associated with downregulation of gene expression and cell lines exposed to demethylating agent resulted in profound reactivated gene expression. We also showed that the promoter methylation in the PCDH10 gene occurs at an earliest identifiable stage of low‐grade squamous intraepithelial lesion. Our studies demonstrate that inactivation of PCDH10 may be a critical event in CC progression and form a potentially useful therapeutic target for CC. © 2009 Wiley‐Liss, Inc.
N‐acetylcysteine improves renal hemodynamics in rats with cisplatin‐induced nephrotoxicity
Authors: Abdelrahman Aly M. , Al Salam Suhail , AlMahruqi Ahmed S , Al husseni Ishaq S. , Mansour Mohamed A , Ali Badreldin H.
Published: August 2009

This work investigated the effect of N‐acetylcysteine (NAC), on renal hemodynamics in cisplatin (CP)‐induced nephrotoxicity in Wistar–Kyoto (WKY) rats. The animals were divided into four groups (n = 5 or 6). The first and second groups received normal saline (control) and intraperitoneal (i.p.) N‐acetylcysteine (500 mg kg−1 per day for 9 days), respectively. The third and fourth groups were given a single intraperitoneal (i.p.) injection of CP (5 mg kg−1) and an i.p. injection of CP (5 mg kg−1) together with i.p. NAC (500 mg kg−1 per day for 9 days), respectively. At the end of the experiment, rats were anesthetized and blood pressure and renal blood flow were monitored, followed by intravenous (i.v.) injection of norepinephrine (NE) for measurement of renal vasoconstrictor responses. CP caused a significant reduction in renal blood flow but did not affect NE‐induced renal vasoconstriction. In addition, CP significantly increased plasma concentrations of urea and creatinine and urinary N‐acetyl‐β‐D‐glucosaminidase (NAG) activity and kidney relative weight. CP decreased body weight and creatinine clearance. Histopathologically, CP caused remarkable renal damage compared with control. NAC alone did not produce any significant change in any of the variables measured. However, NAC significantly ameliorated CP‐induced hemodynamic, biochemical and histopathological changes. The concentration of platinum in the kidneys of CP ? NAC treated rats was less than in CP‐treated rats by 37%. The results show that administration of i.p. NAC (500 mg kg−1 per day for 9 days) reversed the renal hemodynamic changes as well as the biochemical and histopathological indices of CP‐induced nephrotoxicity in WKY rats. Copyright © 2009 John Wiley & Sons, Ltd.
Phosphorylation of Phospholipase C‐δ1 Regulates its Enzymatic Activity
Authors: Fujii Makoto , Yi Kye Sook , Kim Myung Jong , Ha Sang Hoon , Ryu Sung Ho , Suh Pann‐Ghill , Yagisawa Hitoshi
Published: August 2009

Phosphorylation of phospholipase C‐δ1 (PLC‐δ1) in vitro and in vivo was investigated. Of the serine/threonine kinases tested, protein kinase C (PKC) phosphorylated the serine residue(s) of bacterially expressed PLC‐δ1 most potently. It was also demonstrated that PLC‐δ1 directly bound PKC‐α via its pleckstrin homology (PH) domain. Using deletion mutants of PLC‐δ1 and synthetic peptides, Ser35 in the PH domain was defined as the PKC mediated in vitro phosphorylation site of PLC‐δ1. In vitro phosphorylation of PLC‐δ1 by PKC stimulated [3H]PtdIns(4,5)P2 hydrolyzing activity and [3H]Ins(1,4,5)P3‐binding of the PLC‐δ1. On the other hand, endogenous PLC‐δ1 was constitutively phosphorylated and phosphoamino acid analysis revealed that major phosphorylation sites were threonine residues in quiescent cells. The phosphorylation level and the species of phosphoamino acid were not changed by various stimuli such as PMA, EGF, NGF, and forskolin. Using matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry, we determined that Thr209 of PLC‐δ1 is one of the constitutively phosphorylated sites in quiescent cells. The PLC activity was potentiated when constitutively phosphorylated PLC‐δ1 was dephosphorylated by endogenous phosphatase(s) in vitro. Additionally, coexpression with PKC‐α reduced serine phosphorylation of PLC‐δ1 detected by an anti‐phosphoserine antibody and PLC‐δ1‐dependent basal production of inositol phosphates in NIH‐3T3 cells, suggesting PKC‐α activates phosphatase or inactivates another kinase involved in PLC‐δ1 serine phosphorylation to modulate the PLC‐δ1 activity in vivo. Taken together, these results suggest that PLC‐δ1 has multiple phosphorylation sites and phosphorylation status of PLC‐δ1 regulates its activity positively or negatively depends on the phosphorylation sites. J. Cell. Biochem. 108: 638–650, 2009. © 2009 Wiley‐Liss, Inc.
Mindfulness and attention deficit hyperactivity disorder
Authors: Smalley Susan L. , Loo Sandra K. , Hale T. Sigi , Shrestha Anshu , McGough James , Flook Lisa , Reise Steven
Published: August 2009

Attention deficit hyperactivity disorder (ADHD) is a disorder characterized by attentional difficulties. Mindfulness is a receptive attention to present experience. Both ADHD and mindfulness are associated with attention and personality. This study tests whether individuals with ADHD have lower mindfulness scores than controls and, if true, whether personality contributes to these differences. One hundred and five adults (half with ADHD) were assessed for mindfulness, using the Kentucky Inventory of Mindfulness Skills, and personality, using the Tridimensional Character Inventory. Individuals with ADHD report themselves as less mindful than non‐ADHD controls and more novelty‐seeking, less self‐directed, and more self‐transcendent. Mindfulness is negatively associated with ADHD and positively associated with self‐directedness and self‐transcendence. Analyses of subscales of mindfulness suggest that ADHD is associated most with the “Acting in Awareness” dimension, perhaps because of shared items reflecting attentional variability. The current findings support that a large portion of variability in trait mindfulness can be explained by ADHD status and personality traits of self‐directedness and self‐transcendence. It further suggests that interventions that increase mindfulness might improve symptoms of ADHD and increase self‐directedness and/or self‐transcendence. © 2009 Wiley Periodicals, Inc. J Clin Psychol 65: 1–12, 2009.
Caffeic acid phenethyl ester, an active component of honeybee propolis attenuates osteoclastogenesis and bone resorption via the suppression of RANKL‐induced NF‐κB and NFAT activity
Authors: Ang Estabelle S.M. , Pavlos Nathan J. , Chai Lee Y. , Qi Ming , Cheng Tak S. , Steer James H. , Joyce David A. , Zheng Ming H. , Xu Jiake
Published: August 2009

Receptor activator NF‐κB ligand (RANKL)‐activated signaling is essential for osteoclast differentiation, activation and survival. Caffeic acid phenethyl ester (CAPE), a natural NF‐κB inhibitor from honeybee propolis has been shown to have anti‐tumor and anti‐inflammatory properties. In this study, we investigated the effect of CAPE on the regulation of RANKL‐induced osteoclastogenesis, bone resorption and signaling pathways. Low concentrations of CAPE (<1 µM) dose dependently inhibited RANKL‐induced osteoclastogenesis in RAW264.7 cell and bone marrow macrophage (BMM) cultures, as well as decreasing the capacity of human osteoclasts to resorb bone. CAPE inhibited both constitutive and RANKL‐induced NF‐κB and NFAT activation, concomitant with delayed IκBα degradation and inhibition of p65 nuclear translocation. At higher concentrations, CAPE induced apoptosis and caspase 3 activities of RAW264.7 and disrupts the microtubule network in osteoclast like (OCL) cells. Taken together, our findings demonstrate that inhibition of NF‐κB and NFAT activation by CAPE results in the attenuation of osteoclastogenesis and bone resorption, implying that CAPE is a potential treatment for osteolytic bone diseases. J. Cell. Physiol. 221: 642–649, 2009. © 2009 Wiley‐Liss, Inc.
Live FISH: Imaging mRNA in living neurons
Authors: Simon Becky , Sandhu Maneek , Myhr Karen L.
Published: August 2009

This paper describes a novel technique to identify and study neurons that express specific mRNAs. The method is called Live FISH because it is like fluorescent in situ hybridization (FISH) but can be applied to living tissues. In Live FISH, molecular beacons, which fluoresce only in the presence of the complementary mRNA, are delivered by gene gun into living neurons. One of its many benefits over existing gene expression assays is that the neurons are alive. Because identified neurons are living, they can be targeted for subsequent single‐cell assays, such as electrophysiology. In addition, dye delivered with the molecular beacons illuminates dendritic morphology. Live FISH is cheaper than generating transgenic animals, and the endogenous mRNA is assayed without covalent modification or genetic manipulation. This report demonstrates the feasibility of Live FISH with yellow fluorescent protein (YFP) mRNA in living mouse retinas, although molecular beacons can be rationally designed to any mRNA of interest. © 2009 Wiley‐Liss, Inc.
Somatic Ca2+ signaling in cerebellar Purkinje neurons
Authors: Gruol D.L. , Netzeband J.G. , Nelson T.E.
Published: August 2009

Activity‐driven Ca2+ signaling plays an important role in a number of neuronal functions, including neuronal growth, differentiation, and plasticity. Both cytosolic and nuclear Ca2+ has been implicated in these functions. In the current study, we investigated membrane‐to‐nucleus Ca2+ signaling in cerebellar Purkinje neurons in culture to gain insight into the pathways and mechanisms that can initiate nuclear Ca2+ signaling in this neuronal type. Purkinje neurons are known to express an abundance of Ca2+ signaling molecules such as voltage‐gated Ca2+ channels, ryanodine receptors, and IP3 receptors. Results show that membrane depolarization evoked by brief stimulation with K+ saline elicits a prominent Ca2+ signal in the cytosol and nucleus of the Purkinje neurons. Ca2+ influx through P/Q‐ and L‐type voltage‐gated Ca2+ channels and Ca2+‐induced Ca2+ release (CICR) from intracellular stores contributed to the Ca2+ signal, which spread from the plasma membrane to the nucleus. At strong K+ stimulations, the amplitude of the nuclear Ca2+ signal exceeded that of the cytosolic Ca2+ signal, suggesting the involvement of a nuclear amplification mechanism and/or differences in Ca2+ buffering in these two cellular compartments. An enhanced nuclear Ca2+ signal was more prominent for Ca2+ signals elicited by membrane depolarization than for Ca2+ signals elicited by activation of the metabotropic glutamate receptor pathway (mGluR1), which is linked to Ca2+ release from intracellular stores controlled by the IP3 receptor. © 2009 Wiley‐Liss, Inc.
Single doublecortin gene therapy significantly reduces glioma tumor volume
Authors: Santra Manoranjan , Zheng Xuguang , Roberts Cindi , Santra Sutapa , Lu Mei , Panda Swayamprava , Jiang Feng , Chopp Michael
Published: August 2009

We employed lentivirus‐based doublecortin (DCX), as a glioma suppressor gene therapy in an intracranial glioma tumor xenograft model in nude rats. Single DCX‐expressing lentivirus was directly administered into the tumor on day 8 after U87 tumor cell implantation. DCX treatment significantly reduced U87 glioma tumor volume (∼60%) on day 14 after DCX lentivirus injection and significantly improved median survival of tumor‐bearing nude rats. DCX synthesis induced neuronal markers MAP2, TUJ1, and PSA‐NCAM and the glial marker glial fibrillary acidic protein (GFAP) in the implanted U87 glioma tumors. DCX synthesis induced GFAP that colocalized with tubulin in the mitotic stage, inhibited cleavage furrow during cytokinesis, and blocked mitosis in glioma cells. DCX lentivirus infection did not induce apoptosis but significantly inhibited expression of the proliferation marker Ki‐67 and the blood vessel marker von‐Willebrand factor (vWF). U87 and other glioma cells except for brain tumor stem cells (BTSCs) do not express neuronal markers or both neuronal and glial markers. DCX‐synthesizing glioma cells express a phenotype of antiangiogenic BTSC‐like cells with terminal differentiation that causes remission of glioma cells by blocking mitosis via a novel DCX/GFAP pathway. Direct local delivery of lentivirus‐based DCX gene therapy is a potential differentiation‐based therapeutic approach for the treatment of glioma. © 2009 Wiley‐Liss, Inc.
Reticulon 3 is an interacting partner of the SALM family of adhesion molecules
Authors: Chang Kai , Seabold Gail K. , Wang Chang‐Yu , Wenthold Robert J.
Published: August 2009

Synaptic adhesion‐like molecules (SALMs) are a recently discovered family of adhesion molecules that is widely distributed in the central nervous system and has been implicated in neurite outgrowth and synapse formation. To identify proteins that interact with extracellular domains of SALMs, we carried out yeast two‐hybrid screening using the extracellular domain of SALM1 as bait. A clone encoding full‐length reticulon 3A1 was isolated. This interaction was shown to occur through the LRR domain, which is found on all SALMs. To determine whether this relationship also occurs in brain, we performed immunoprecipitation using antibodies to SALMs 1–4. A 19‐kDa band, identified as reticulon 3C, bound to all four SALMs, whereas a 90‐kDa band, which did not comigrate with any known reticulon 3 variant, bound to SALMs 2 and 3. These results show that reticulon 3 may play a role in the trafficking of the SALM family of adhesion molecules. Published 2009 Wiley‐Liss, Inc.
Sodium‐calcium interactions with growth, water, and photosynthetic parameters in salt‐treated beans
Authors: Cabot Catalina , Sibole John V. , Barceló Juan , Poschenrieder Charlotte
Published: August 2009

Calcium (Ca2+) amelioration of the plant's growth response to salinity depends on genetic factors. In this work, supplemental Ca2+ did not improve growth in Phaseolus vulgaris L. cv. Contender under high‐saline conditions and negatively affected several physiological parameters in nonsalinized plants. The response to supplemental Ca2+ was examined using plants grown in 25% modified Hoagland solution at different Na+ : Ca2+ ratios. In control plants (1 mM Ca2+; 1 mM Na+) surplus Ca2+ (4 or 10 mM) was associated with stomatal closure, decrease of hydraulic conductivity, sap flow, leaf specific dry weight, leaf K+ and leaf Mg2+ concentrations, and inhibition of CO2 assimilation. Leaf water content was enhanced, while water‐use efficiency and dry matter were unaffected during the 15 d experimental period. The Ca2+ effect was not cation‐specific since similar results were found in plants supplied with high external Mg2+ or with a combination of Ca2+ and Mg2+. Relative to control plants, salinization (50 and 100 mM NaCl) caused a decrease in dry matter, hydraulic conductivity, sap flow, leaf Mg2+ activity, and inhibition of stomatal opening and CO2 assimilation. However, NaCl (50 and 100 mM NaCl) enhanced leaf K+ concentration and water‐use efficiency. At 100 mM NaCl, leaf water content also significantly increased. Supplemental Ca2+ had no amelioration effect on the salt‐stress response of this bean cultivar. In contrast, the 50 mM–NaCl treatment improved stomatal conductance and CO2‐assimilation rate in plants exposed to the highest Ca2+ concentration (10 mM). Phaseolus vulgaris is classified as a very NaCl‐sensitive species. The similarities in the effects caused by supplemental Ca2+, supplemental Mg2+, and NaCl salinity suggest that P. vulgaris cv. Contender has a high non‐ion‐specific salt sensitivity. On the other hand, the improvement in gas‐exchange parameters in Ca2+‐supplemented plants by high NaCl could be the result of specific Na+‐triggered responses, such as an increase in the concentration of K+ in the leaves.
Megadroughts in North America: placing IPCC projections of hydroclimatic change in a long‐term palaeoclimate context
Authors: Cook Edward R. , Seager Richard , Heim Richard R. , Vose Russell S. , Herweijer Celine , Woodhouse Connie
Published: August 2009

IPCC Assessment Report 4 model projections suggest that the subtropical dry zones of the world will both dry and expand poleward in the future due to greenhouse warming. The US Southwest is particularly vulnerable in this regard and model projections indicate a progressive drying there out to the end of the 21st century. At the same time, the USA has been in a state of drought over much of the West for about 10 years now. While severe, this turn of the century drought has not yet clearly exceeded the severity of two exceptional droughts in the 20th century. So while the coincidence between the turn of the century drought and projected drying in the Southwest is cause for concern, it is premature to claim that the model projections are correct. At the same time, great new insights into past drought variability over North America have been made through the development of the North American Drought Atlas from tree rings. Analyses of this drought atlas have revealed past megadroughts of unprecedented duration in the West, largely in the Medieval period about 1000 years ago. A vastly improved Living Blended Drought Atlas (LBDA) for North America now under development reveals these megadroughts in far greater detail. The LBDA indicates the occurrence of the same Medieval megadroughts in the West and similar‐scale megadroughts in the agriculturally and commercially important Mississippi Valley. Possible causes of these megadroughts and their implications for the future are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
CNT Based Elastomer‐Hybrid‐Nanocomposites with Promising Mechanical and Electrical Properties
Authors: Fritzsche Juliane , Lorenz Hagen , Klüppel Manfred
Published: August 2009

CNT based elastomer‐hybrid‐nanocomposites prepared by melt mixing have been investigated showing promising results in technologically relevant electrical, mechanical, and fracture‐mechanical properties. It is demonstrated that the incorporation of CNT in silica‐filled natural rubber results in a good dispersion of the CNT. The materials show an enhanced mechanical stiffness and tensile strength, an increased modulus, and a high electrical conductivity with quite low amounts of CNT, though the tear resistance under dynamical loading is slightly reduced. Using DMA and dielectric spectra, a better understanding of the conduction mechanism, the polymer/tube interaction, and the filler networking in CNT nanocomposites is achieved.

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Plasma Functionalization of Multiwalled Carbon Nanotube Bucky Papers and the Effect on Properties of Melt‐Mixed Composites with Polycarbonate
Authors: Pötschke Petra , Zschoerper Nicolas Peer , Moller Björn P. , Vohrer Uwe
Published: August 2009

Multiwalled carbon nanotubes in the form of bucky papers were modified using Ar/O2 plasma and thereafter melt‐mixed into polycarbonate. The effect of plasma modification on the nanotubes was followed by XPS, indicating the formation of carboxylic or ester groups at the nanotube surfaces. In the melt‐mixed nanocomposites, the modified nanotubes exhibited a better macrodispersion and better phase adhesion to the matrix as evidenced by morphological investigations. The electrical percolation threshold was not altered and occurred below 0.5 wt.‐% nanotubes. The mechanical properties were improved by having higher values of stress at yield, stress beyond the yield point, and strain at break illustrating the effect of both better dispersion and enhanced phase adhesion.

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Annular Multi‐Shelled Spherulites in Interiors of Bulk‐Form Poly(nonamethylene terephthalate)
Authors: Chen Yu‐Fan , Woo Eamor M.
Published: August 2009

Morphology of crystallized spherulites in poly(nonamethylene terephthalate) (PNT) in bulk forms, instead of thin‐film forms, was investigated using scanning electron microscopy (SEM), polarized‐optical microscopy (POM), and transmission electron microscopy (TEM). Ring textures were found to exist on the fractured surfaces or microtomed films from bulk PNT samples. By further SEM and TEM examinations, the fracture surfaces and microtomed films from the interior of the bulk display similar ring‐banded patterns as those in thin films cast on glass slides. Although the cast PNT thin films in two‐dimensional growth are known to display both Type‐1 ring bands as majority and Type‐2 ring bands as minority, this study further shows that the interior of PNT bulk exhibits mainly Type‐1 (single rings with narrower spacing than Type‐2) ring bands, and Type‐2 spherulites exist sporadically in three‐dimensional forms. From these analyses on the ring bands in the interiors of bulk‐form PNT crystallized at several specific temperatures, it can be proposed that the growth of spherulites in three dimensions is layer‐by‐layer, packing into a multi‐shells structure in three‐dimensional ring‐banded spheres.

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One‐Dimensional V2O5@Polyaniline Core/Shell Nanobelts Synthesized by an In situ Polymerization Method
Authors: Li Guicun , Zhang Chuanqin , Peng Hongrui , Chen Kezheng
Published: August 2009

Uniform one‐dimensional V2O5@polyaniline core/shell nanobelts have been fabricated by a simple in‐situ polymerization method in the absence of any surfactant and additional initiator. The influences of pH and additional initiator on the morphology of the resulting products are investigated. The pH value is important for the formation of V2O5@polyaniline core/shell nanobelts, which preserve the original morphology of V2O5 nanobelts. With a decrease in the pH value to 0 the original morphology of the V2O5 nanobelts is destroyed. When ammonium peroxydisulfate is used, some separated polyaniline nanofibers are formed. The formation of the V2O5@polyaniline core/shell nanobelts can be related to the in‐situ polymerization of aniline monomer by etching V2O5 nanobelts. The electrochemical lithium intercalation/deintercalation of V2O5@polyaniline core/shell nanobelts is investigated by cyclic voltammograms.

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Synthesis of CdSe–Poly(N‐vinylcarbazole) Nanocomposite by Atom Transfer Radical Polymerization for Potential Optoelectronic Applications
Authors: Wang Tzong‐Liu , Yang Chien‐Hsin , Shieh Yeong‐Tarng , Yeh An‐Chi
Published: August 2009

A hybrid inorganic–polymer nanocomposite using CdSe nanocrystals with high electron mobility has been successfully synthesized by atom transfer radical polymerization (ATRP). First the hydroxyl‐coated CdSe nanoparticles (i.e., CdSe–OH) were prepared via a wet chemical route. A polymerization initiator was then prepared for ATRP of N‐vinylcarbazole. FT‐IR, 1H NMR, and XRD analyses confirmed the successful synthesis of CdSe–poly(N‐vinylcarbazole) (PVK) nanohybrid. UV–Vis spectra and photoluminescence data revealed that grafting of PVK onto the surface of CdSe nanocrystals would reduce the band gap of PVK and cause the red shift of emission peak. TEM and SEM micrographs exhibited CdSe nanoparticles that were well‐coated with PVK polymer.

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H2O, H2, HF, F2 and F2O nuclear magnetic shielding constants and indirect nuclear spin–spin coupling constants (SSCCs) in the BHandH/pcJ‐n and BHandH/XZP Kohn–Sham limits
Authors: Kupka Teobald
Published: August 2009

Good performance of segmented contracted basis sets XZP, where X = D, T, Q and 5, for obtaining H2O, H2, HF, F2 and F2O nuclear isotropic shielding constants in the BHandH Kohn–Sham basis set limit was shown. The results of two‐ and three‐parameter complete basis set limit extrapolation schemes were compared with experimental results, earlier literature data and benchmark ab initio results. Similar convergence patterns of shieldings obtained from calculations using general purpose XZP basis sets and from polarization‐consistent basis sets pcS‐n and pcJ‐n, where n = 0, 1, 2, 3 and 4, designed to accurately predict magnetic properties were observed. On the contrary, the SSCCs were more sensitive to the XZP basis set size and generally less accurate than those estimated using pcJ‐n basis set family. The BHandH density functional markedly outperforms B3LYP method in predicting heavy atom shieldings and SSCCs values in the studied systems. Copyright © 2009 John Wiley & Sons, Ltd.
Stochastic identification of elastic constants for anisotropic materials
Authors: Furukawa Tomonari , Pan Jan Wei
Published: August 2009

This paper presents an energy‐based characterization technique that stochastically identifies the elastic constants of anisotropic materials by modeling the measurement noise and removing its effect unlike conventional deterministic techniques, which deterministically identify the elastic constants directly from noisy measurements. The technique recursively estimates the elastic constants at every acquisition of measurements using Kalman Filter. Owing to the non‐linear expression of the measurement model, a Kalman gain has been newly derived and achieves optimal estimation. Since the variances in addition to the means are computed, the proposed technique can not only identify the elastic constants but also describe their certainty as an additional advantage. The validity of the proposed technique and its superiority to the conventional technique were first demonstrated via parametric studies of low‐dimensional problems. The proposed technique was then successfully applied to the identification of elastic constants of an anisotropic material. Copyright © 2009 John Wiley & Sons, Ltd.
Polymerization kinetics and microstructure of waterborne acrylic/alkyd nanocomposites synthesized by miniemulsion
Authors: Goikoetxea Monika , Minari Roque J. , Beristain Itxaso , Paulis María , Barandiaran María J. , Asua José M.
Published: August 2009

Waterborne acrylic‐alkyd nanocomposites are expected to combine the positive properties of alkyd resins and acrylic polymers. In this work, the kinetics of the miniemulsion polymerization used to synthesize these nanocomposites and the effect of the process variables on the polymer architecture and particle morphology was investigated. It was found that resin hydrophobicity and the type of initiator strongly affected the microstructure of these materials. The mechanisms responsible for these effects were discussed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4871–4885, 2009
Synthesis and properties of fluorine‐containing amphiphilic graft copolymer P(HFMA)‐g‐P(SPEG)
Authors: Xiong Sheng‐Dong , Li Ling , Wu Shui‐Lin , Xu Zu‐Shun , Chu Paul K.
Published: August 2009

A series of amphiphilic graft copolymers P(HFMA)‐g‐P(SPEG) comprising poly(hexafluorobutyl methacrylate) (PHFMA) backbones and poly(ethylene glycol) (PEG) side chains were synthesized by copolymerization of HFMA and SPEG macromonomer with the p‐vinylbenzyl end group. The SPEG macromonomer was synthesized by reacting Methoxy poly(ethylene glycol) (MPEG) with p‐chloromethylstyrene in THF in the presence of NaH. The macromonomer and amphiphilic graft copolymer were characterized by FTIR, 1H NMR, 19F NMR, and gel permeation chromatography (GPC). The critical micelle concentration (CMC) of the amphiphilic graft copolymer was measured by surface tension technique. The results showed that the CMC decreased with increasing HFMA contents in the graft copolymers. The interaction between P(HFMA)‐g‐P(SPEG) and bovine serum albumin (BSA) was studied by fluorescence spectroscopy, transmission electron microscopy (TEM), and photon correlation spectroscopy (PCS). The fluorescence spectrum showed that the fluorescence intensity of BSA increased with increasing content of HFMA in P(HFMA)‐g‐P(SPEG) and concentration of P(HFMA)‐g‐P(SPEG) in the P(HFMA)‐g‐P(SPEG)/BSA solution. TEM micrographs showed that P(HFMA)‐g‐P(SPEG) mainly formed core‐shell structure micelles. When BSA was added, the micelles changed from a core‐shell structure into a worm‐like, vesicle‐like and hollow‐like structure with different initial concentrations of the copolymer. The size distribution of the micelles increased proving that the copolymer micelles encapsulated the bovine serum albumin. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4895–4907, 2009
Fabrication and properties of hollow poly(N‐isopropylacrylamide)‐Ag nanocomposite spheres
Authors: Xie Lin , Chen Min , Wu Limin
Published: August 2009

This article presents a strategy for the fabrication of hollow poly(N‐isopropylacrylamide) (PNIPAM)‐Ag nanocomposite spheres. In this approach, the thermosensitive PNIPAM hollow spheres were first synthesized via a one‐pot “self‐removing” process and then used as supporters for the coordination and in situ reduction of Ag+ ions. The results show that these hollow PNIPAM‐Ag nanocomposite spheres still have typical thermal sensitivity, and importantly, these spheres have very good and controllable catalytic activity with five stages of variation versus temperature. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4919–4926, 2009
Tridentate anilido‐aldimine magnesium and zinc complexes as efficient catalysts for ring‐opening polymerization of ε‐caprolactone and L‐lactide
Authors: Tsai Yueh‐Hsuan , Lin Chia‐Her , Lin Chu‐Chieh , Ko Bao‐Tsan
Published: August 2009

A novel tridentate anilido‐aldimine ligand, [o‐C6H4(NHAr)HCNCH2CH2NMe2] (Ar = 2,6‐iPr2C6H3, L‐H, 1), has been prepared by the condensation of N, N‐dimethylethylenediamine with one molar equivalent of 2‐fluoro‐benzaldehyde in hexane, followed by the addition of the lithium salt of diisopropylaniline in THF. Magnesium (Mg) and zinc (Zn) complexes supported by the tridentate anilido‐aldimine ligand have been synthesized and structurally characterized. Reaction of L‐H (1) with an equivalent amount of MgnBu2 or ZnEt2 produces the monomeric complex [LMgnBu] (2) or [LZnEt] (3), respectively. Experimental results show that complexes 2 and 3 are efficient catalysts for ring‐opening polymerization of ε‐caprolactone (CL) and L‐lactide (LA) in the presence of benzyl alcohol and catalyze the polymerization of ε‐CL and L‐LA in a controlled fashion yielding polymers with a narrow polydispersity index. In both polymerizations, the activity of Mg complex 2 is higher than that of Zn complex 3, which is probably due to the higher Lewis acidity and better oxophilic nature of Mg2+ metal. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4927–4936, 2009
Asymmetric reduction of aromatic ketimines in the presence of helical polymer as catalyst
Authors: Terada Kayo , Masuda Toshio , Sanda Fumio
Published: August 2009

Novel optically active ethynyl monomers were synthesized from L‐valine and N‐methyl‐L‐valine, and polymerized with a rhodium catalyst to provide the polymers with number‐average molecular weights over 200,000 in good yields. The CD and UV‐vis spectra of the polymers indicated that they took helical structures with predominantly one‐handed screw sense in solution. The polymers served as catalysts of asymmetric reduction of aromatic ketimines to afford optically active amines in moderate yields. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4971–4981, 2009
Low Temperature Growth of Photoactive Titania by Atmospheric Pressure Plasma
Authors: Hodgkinson John L. , Yates Heather M. , Sheel David W.
Published: August 2009

Atmospheric pressure glow discharge plasma CVD was used to deposit thin films of titania at 200 °C using two different precursors. The resulting films were characterised using techniques including XPS, RBS and XRD. It was established that annealing at temperatures as low as 275 °C produced crystalline films that were photocatalytically active. When annealed at 300 °C the photoactivity was greater than that of commercially available “self‐cleaning” titania films. The effects of the different precursors, annealing times and temperatures on the crystallinity and photoactivity are discussed.

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Titanium Nitriding by Microwave Atmospheric Pressure Plasma: Towards Single Crystal Synthesis
Authors: Cardoso R. P. , Arnoult G. , Belmonte Thierry , Henrion G. , Weber Sylvian
Published: August 2009

High temperature titanium nitriding is achieved by plasmas sustained at atmospheric pressure in a microwave resonant cavity. TiN layers produced in the temperature range (1 475–1 980 K) present a grain orientation that is mainly defined by initial grain orientation of the titanium substrate. Coarsening pretreatments on the titanium samples before nitriding allows the synthesis of a strongly oriented TiN layer. The TiN + α‐Ti layer thickness reaches about 116 µm after a 1 h treatment at 1 760 K. For these treatment times, the bulk material is not totally transformed into TiN, but this is a first step towards the synthesis of single crystals of TiN from commercial‐grade pure titanium.
Microplasma Stamps for Area‐Selective Modification of Polymer Surfaces
Authors: Lucas Nina , Franke Raimo , Hinze Alena , Klages Claus‐Peter , Frank Ronald , Büttgenbach Stephanus
Published: August 2009

Microplasma stamps based upon the principle of dielectric barrier discharges are applied to a new type of area‐selective surface modification process at atmospheric pressure. This process integrates the surface treatment and lateral microstructuring within one process step. For this purpose, the plasma is ignited in cavities which are formed temporarily by compressing the microplasma stamp and the substrate to be treated. In this work, we investigate the influence of the cavity design and the ignition conditions on the surface treatment. Furthermore, peptide synthesis on area‐selectively treated poly(propylene) surfaces is presented as an application.
Influence of Atmospheric Plasma Source and Gas Composition on the Properties of Deposited Siloxane Coatings
Authors: Dowling Denis P. , Ramamoorthy Amsarani , Rahman Mahfujur , Mooney Damian A. , MacElroy J. M. Don
Published: August 2009

Siloxane coatings were deposited using two different atmospheric plasma systems namely a reel‐to‐reel atmospheric plasma liquid deposition system called Labline™ and an atmospheric plasma jet system called PlasmaStream™. Both systems combine an atmospheric plasma, with the use of liquid precursors. The influence of the plasma source and processing conditions on the deposited coating properties were studied. The coatings were deposited onto Vycor glass and silicon wafer substrates from a liquid tetraethyl orthosilicate (TEOS) precursor which was nebulized into both He and He/O2 plasmas. Higher film growth rates were obtained using the plasma jet system; however, the reel‐to‐reel system facilitated the larger area coating of webs. The thickness (spectroscopic ellipsometry measurements) and water contact angle profile of the films deposited using the jet system on silicon wafer substrates in static mode were investigated. Amongst the other coatings characterization techniques used to evaluate the deposited coatings were optical profilometry, XPS, SEM, and AFM. The formation of particulates due to excess gas‐phase reactions during the atmospheric plasma deposition of coatings has been widely reported. In this study, larger number of particulates were observed under the conditions of higher plasma power, with the addition of O2 into the He plasma and also at low TEOS flow rates. The introduction of N2 into the He/O2 plasma, during the deposition of siloxane coatings led to a significant reduction in the number of particulates generated for both plasma sources. Nitrogen gas flow rate was varied systematically and a correlation was obtained on the influence of the flow rate of this gas on surface roughness and particulate formation.
Tribological Performance of CrAlSiN Coatings at High Temperatures
Authors: Polcar Tomas , Vitu Tomas , Sondor Jozef , Cavaleiro Albano
Published: August 2009

Chromium aluminum nitride (CrAlN) coatings produced by PVD are routinely deposited on tools and tested as components for machining and forming applications. However, the addition of a doping element, such as Si, can further improve the properties of such coatings. In this study, CrAlN and CrAlSiN coatings with different Cr/Al ratio were prepared on WC substrates by low cathodic arc deposition and their structure and tribological properties analyzed in situ at high temperatures. In spite of excellent thermal stability and oxidation resistance, the hot‐sliding tests showed unsatisfactory coating behavior.
Optical Emission Spectroscopy of Argon–Fluorocarbon–Oxygen Fed Atmospheric Pressure Dielectric Barrier Discharges
Authors: Fanelli Fiorenza
Published: August 2009

Atmospheric pressure filamentary dielectric barrier discharges (FDBDs) fed with argon, a fluorocarbon compound (i.e. CF4, C3F8, C3F6 and c‐C4F8) and O2 were investigated by optical emission spectroscopy (OES). The UV–Vis spectra of the plasma in argon–fluorocarbon mixtures are characterized by narrow signals from Ar atoms, CF2 and CF fragments and by two continua due to CF and CF3. O2 addition to the feed gas reduces the emissions of fluorocarbon fragments and results in the appearance of an intense narrow emission at 193 nm and of a broad continuum centred at 290 nm ascribed to ArF and Ar2F excimers, respectively. Any signal from F atoms was not detected under the experimental conditions investigated even though the plasma contains F atoms since the dry etching of silicon substrates, a typical process driven by F atoms, was observed. Some possible explanations of this phenomenon are presented.

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Rituximab (B‐cell depleting antibody) associated lung injury (RALI): A pediatric case and systematic review of the literature
Authors: Bitzan Martin , Anselmo Mark , Carpineta Lucy
Published: August 2009

Introduction

Pulmonary toxicity of delayed onset is a rare complication of B‐lymphocyte depleting antibody therapy and has been almost exclusively reported in older patients with B‐cell malignancies.

Aims

To describe a pediatric patient with rituximab‐associated lung injury (RALI), to systematically analyze previous reports of pulmonary complications, and to summarize common clinico‐pathological features, treatment, and outcome.

Results

A teenage boy with focal segmental glomerulosclerosis (FSGS) presented with progressive dyspnea, fever, hypoxemia and fatigue 18 days after the completion of a second course of rituximab infusions for calcineurin inhibitor‐dependent nephrotic syndrome. Respiratory symptoms started while he received high‐dose prednisone for persistent proteinuria. Bilateral, diffuse ground‐glass infiltrates corresponded to the presence of inflammatory cells in the bronchioalveolar lavage fluid. Empiric antibiotic treatment including clarithromycin was given, but the microbiological work‐up remained negative. Serum IgE, C3, and C4 concentrations were normal. He recovered within 3 weeks after onset.

We systematically reviewed 23 reports describing 30 additional cases of rituximab‐associated lung disease. Twenty eight patients had received rituximab for B‐cell malignancies, one for graft‐versus‐host disease and one for immune thrombocytopenia. Median age was 64 years (interquartile range [IQR] 58–69 years). Seventy one percent received concomitant chemotherapy. Time to onset from the last rituximab dose was 14 days (IQR 11–22 days). Eleven of 31 patients required mechanical ventilation, and 9 died (29%). Ventilation was a significant predictor of fatal outcome (odds ratio 46.7; confidence interval 9.5–229.9). High dose glucocorticoid therapy did not improve survival or prevent severe lung disease or death.

Conclusions

With the expanding use of rituximab for novel indications, additional cases of RALI affecting younger age groups are expected to emerge. Mechanical ventilation predicts poor outcome. Glucocorticoids may not be protective. Pediatr Pulmonol. 2009; 44:922–934. © 2009 Wiley‐Liss, Inc.
Effects of the 5 alpha‐reductase inhibitor dutasteride on gene expression in prostate cancer xenografts
Authors: Schmidt Lucy J. , Regan Kevin M. , Anderson S. Keith , Sun Zhifu , Ballman Karla V. , Tindall Donald J.
Published: August 2009

BACKGROUND

In the prostate, androgens play a crucial role in normal and cancerous growth; hence the androgenic pathway has become a target of therapeutic intervention. Dutasteride is a 5 alpha‐reductase (5AR) inhibitor currently being evaluated both for chemoprevention and treatment of prostate cancer. Dutasteride inhibits both 5AR I and II enzymes, effectively blocking conversion of testosterone to dihydrotestosterone (DHT) in the prostate. This greatly reduces the amount of the active ligand DHT available for binding to the androgen receptor (AR) and stimulating proliferation, making this a good candidate for chemoprevention of prostate cancer. In this study, we sought to determine how dutasteride is functioning at the molecular level, using a prostate cancer xenograft model.

METHODS

Androgen‐responsive LuCaP 35 xenograft tumors were grown in Balb/c mice. Subcutaneously implanted time‐release pellets were used for drug delivery. Microarray analysis was performed using the Affymetrix HG‐U133Av2 platform to examine changes in gene expression in tumors following dutasteride treatment.

RESULTS

Dutasteride significantly reduced tumor growth in LuCaP 35 xenografts by affecting genes involved in apoptotic, cytoskeletal remodeling, and cell cycle pathways among others. Notably, genes in the Rho GTPase signaling pathway, shown to be important in androgen‐deprivation conditions, were significantly up‐regulated.

CONCLUSION

We have identified multiple pathways outside of the androgenic pathway in prostate cancer xenografts affected by treatment with dutasteride. These findings provide insights into the function of dutasteride within the tumor microenvironment, potentially allowing for development of agents that can be used in combination with this drug to further enhance its effectiveness. Prostate 69: 1730–1743, 2009. © 2009 Wiley‐Liss, Inc.
Singlet methylene insertion into polar OH and NH bonds of water and ammonia—Ab initio and DFT study
Authors: Ramasami K. , Ramalingam M. , Venuvanalingam P. , Jaccob M.
Published: August 2009

Correlated ab initio molecular orbital, DFT, QCISD, G3MP2, and QCISD(T) calculations have been used to investigate the geometries, energetics, and mechanisms governing the insertion reactions of 1CH2 into OH and NH bonds of water and ammonia, respectively, in gas phase adopting 6‐311++g(d, p) basis set. It is found that 1CH2 reacts with water and ammonia to produce the ylide‐like intermediates H2COH2 and H2CNH3, which in turn undergo 1,2‐hydrogen shift to produce methanol and methylamine, respectively. Results obtained indicate that in the gas phase, the ylides and the transition states are located below the reactants' energy levels. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
DFT investigation of MoS2 nanoclusters used as desulfurization catalysts
Authors: McBride Kendra L. , Head John D.
Published: August 2009

Supported single‐layer MoS2 is a well‐established catalyst used by the petroleum industry to remove sulfur from fossil fuels. It is believed that the catalytic activity occurs at the edge of the MoS2 nanoparticles. Recently, atomic‐scale images of MoS2 nanoclusters under catalytic working conditions have been obtained with scanning tunneling microscopy (STM). These images show that certain triangular‐shaped “magic clusters” are formed, where the triangular shape is attributed to stabilization from excess sulfur at the cluster edges. Much of the recent theoretical rationalization of the MoS2 cluster structures has been formulated by using plane‐wave DFT calculations. However, the clusters observed in the recent STM images are small enough that their structures and properties can be evaluated using direct space DFT calculations. We present the theoretically optimized structures obtained with DFT calculations for the series of Mo10Sx clusters with x = 12, 18, 24, 30, and 36. From consideration of their relative energies and simulated STM images, we find the cluster with the Mo10 core most likely being imaged in the STM experiments is the Mo‐edge cluster Mo10S24. This contrasts with the assignment to the S‐edge cluster Mo10S24 by the experimentalists and their suggestion that Mo‐edge clusters are less favored than S‐edge clusters when there are 21 or less Mo atoms. Furthermore, despite being able to build initial Mo10Sx structures with a high degree of symmetry, we find the fully optimized Mo10Sx clusters to have essentially no symmetry, and we discuss how this could be playing a role in the MoS2 catalytic activity. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Theoretical study on the effects of oxygen doping on the lithium ion conductive perovskite‐type manganese fluoride of KxBa(1−x)/2MnF3
Authors: Onishi Taku
Published: August 2009

Previously, we demonstrated that the lithium ion conduction in the perovskite‐type manganese fluoride is attributed to counter cation‐site vacancy mechanism. The divalent counter cation‐doped KxBa(1−x)/2MnF3 was theoretically predicted as the lithium ion conductor in the perovskite‐type manganese fluoride. In this study, we considered the oxygen doping for KxBa(1−x)/2MnF3 to realize the higher lithium ion conductivity. It is because lithium ion forms the stronger ionic bond with the doped oxygen anion. The hybrid‐DFT calculations were performed to investigate the lithium ion conduction in the oxygen‐doped KxBa(1−x)/2MnF3. The calculation results were discussed from the viewpoints of the potential energy curve, electron densities, and charge and spin densities. The effect of the lithium ion fluctuation was also discussed by calculating the ratio of the diffusion coefficients. Finally, we theoretically predicted the ideal oxygen‐doped structure for KxBa(1−x)/2MnF3. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009