bluuebunny/crossref_metadata_2025 huggingface dataset:
Synaptic input to dentate granule cell basal dendrites in a rat model of temporal lobe epilepsy
Authors: Thind Khushdev K. , Ribak Charles E. , Buckmaster Paul S.
Published: May 2008

In patients with temporal lobe epilepsy some dentate granule cells develop basal dendrites. The extent of excitatory synaptic input to basal dendrites is unclear, nor is it known whether basal dendrites receive inhibitory synapses. We used biocytin to intracellularly label individual granule cells with basal dendrites in epileptic pilocarpine‐treated rats. An average basal dendrite had 3.9 branches, was 612 μm long, and accounted for 16% of a cell's total dendritic length. In vivo intracellular labeling and postembedding GABA‐immunocytochemistry were used to evaluate synapses with basal dendrites reconstructed from serial electron micrographs. An average of 7% of 1,802 putative synapses were formed by GABA‐positive axon terminals, indicating synaptogenesis by interneurons. Ninety‐three percent of the identified synapses were GABA‐negative. Most GABA‐negative synapses were with spines, but at least 10% were with dendritic shafts. Multiplying basal dendrite length/cell and synapse density yielded an estimate of 180 inhibitory and 2,140 excitatory synapses per granule cell basal dendrite. Based on previous estimates of synaptic input to granule cells in control rats, these findings suggest an average basal dendrite receives ≈14% of the total inhibitory and 19% of excitatory synapses of a cell. These findings reveal that basal dendrites are a novel source of inhibitory input, but they primarily receive excitatory synapses. J. Comp. Neurol. 509:190–202, 2008. © 2008 Wiley‐Liss, Inc.
Chemical Solutions in a Quantum Solvent: Anionic Electrolytes in 4He Nanodroplets
Authors: Coccia Emanuele , Marinetti Fabio , Bodo Enrico , Gianturco Francesco A.
Published: May 2008

Variational and diffusion Monte Carlo (VMC and DMC) calculations are presented for anionic electrolytes solvated in 4He. The electrolytes have the general structure X−(He)N, with X=F, Cl, Br and I, and N varying up to 40 (41 for I−). The overall interaction potential is obtained from accurate ab initio data for the two‐body components and then using the sum‐of‐potentials approximation. Our computational scheme is a robust procedure, giving us accurate trial wavefunctions that can be used to perform high‐quality DMC calculations. The results indicate very marked delocalization and permanence of the liquid‐like quantum features of the solvent adatoms surrounding the anionic impurities. This finding stands in contrast to the more structured, solid‐like behavior of the quantum solutions with alkali metal cations embedded in He nanodroplets. While other negatively charged species such as H− have shown an overall repulsive interaction with He, the present calculations clearly indicate that the halogen anions remain solvated within liquid‐like solvent “bubbles” of species‐dependent size.
Synthesis, Structural, Thermal and Magnetic Characterization of a Pyrophosphato‐Bridged Cobalt(II) Complex
Authors: Ikotun Oluwatayo F. , Ouellette Wayne , Lloret Francesc , Kruger Paul E. , Julve Miguel , Doyle Robert P.
Published: May 2008

The reaction in water of CoII sulfate heptahydrate with 1,10‐phenanthroline (phen) and sodium pyrophosphate (Na4P2O7) in a 2:4:1 stoichiometric ratio resulted in the crystallization of a neutral dinuclear CoII complex, {[Co(phen)2]2(μ‐P2O7)}·6MeOH (1), as revealed by a single‐crystal X‐ray diffraction study. The bridging pyrophosphato ligand between the two [Co(phen)2]2+ units in a bis(bidentate) coordination mode places the adjacent metal centers at 4.857 Å distance, and its conformation gives rise to intramolecular π–π stacking interaction between adjacent phen ligands. Indeed, intermolecular π–π stacking interactions between phen ligands from adjacent dinuclear complexes create a supramolecular 2D network in 1. Magnetic susceptibility measurements on a polycrystalline sample of 1 in the temperature range 1.9–295 K are typical of an overall antiferromagnetic coupling with a maximum of the magnetic susceptibility at 3.0 K. The analysis of the magnetic data in the whole temperature range allows the determination of the value of the intramolecular magnetic coupling (J = –1.23 cm–1). The ability of the pyrophosphato ligand to mediate magnetic interactions between different first‐row transition‐metal ions when adopting the bis(bidentate) bridging mode is analyzed and discussed in the light of the small number of magneto‐structural reports on this type of compound, bearing in mind the number of unpaired electrons and type of magnetic orbitals on each metal center. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Chemistry with [18F]Fluoride Ion
Authors: Cai Lisheng , Lu Shuiyu , Pike Victor W.
Published: May 2008

The success of molecular imaging with positron‐emission tomography (PET) depends on the availability of selective molecular probes labeled with positron‐emitters, such asfluorine‐18 (t1/2 = 109.7 min). No‐carrier‐added (NCA) [18F]fluoride ion (18F–) is the primary reagent for the preparation of 18F‐labeled tracers in high specific activity. In this microreview, we survey current and advancing radiochemical methods and technologies for the use of NCA [18F]fluoride ion in the preparation of 18F‐labeled radiotracers for applications with PET. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Naphthyl‐Substituted Carbocations: From peri Interaction to Cyclization
Authors: Dyker Gerald , Hagel Marcel , Henkel Gerald , Köckerling Martin
Published: May 2008

The peri interaction of 1‐functionalized naphthalenes equipped with a triarylmethyl cation at the 8‐position has been studied because of the reversibility of the ring‐closing reaction, which was monitored closely by NMR spectroscopy in the case of the cyclic ammonium salt 5b. Carbocycle 4a and N‐heterocycle 5b did not exhibit any tendency for ring cleavage under various conditions, whereas the naphtho‐annulated furan 4c underwent reversible ring cleavage under strongly acidic conditions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Isoflavone Glycosides: Synthesis and Evaluation as α‐Glucosidase Inhibitors
Authors: Wei Guo , Yu Biao
Published: May 2008

On the basis of the structure of 4′,7,8‐trihydroxyisoflavone 7‐O‐α‐D‐arabinofuranoside (namely A‐76202, 1), a Rhodococcus metabolite showing potent inhibitory activities againstthe α‐glucosidases of rat liver microsome (IC50 = 0.46 ng/mL), 26 analogs, each with minor variations at the sugar moiety and the isoflavone A and B rings, were readily synthesized. Notably, a new and efficient method was developed for the divergent synthesis of the B‐ring congeners of the isoflavone glycosides by using Suzuki–Miyaura coupling as the final step. Modifications at the sugar moiety and the isoflavone A ring significantly diminish the activity, whereas variations at the B ring are largely tolerated for retaining the potent α‐glucosidase inhibitory activity.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis of Oligophenylenevinylene Heptamers Substituted with Fullerene Moieties
Authors: Gégout Aline , Holler Michel , Figueira‐Duarte Teresa M. , Nierengarten Jean‐François
Published: May 2008

Oligophenylenevinylene (OPV) derivatives substituted with one or two fullerene subunits have been prepared starting from a fullerene carboxylic acid derivative and OPV heptamers bearing one or two alcohol functions. The electrochemical properties of the resulting C60‐OPV derivatives have been investigated by cyclic voltammetry. Whereas the fist reduction of both C60–OPV conjugates is centered on the C60 unit, the oxidation is centered on the OPV rod. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Association of depressive symptoms with bone mineral density in older men: a population‐based study
Authors: Laudisio Alice , Marzetti Emanuele , Cocchi Alberto , Bernabei Roberto , Zuccalà Giuseppe
Published: May 2008

Objective

Thirty percent of hip fractures occur in men; nevertheless, the determinants of osteoporosis in men are unclear.

Methods

We assessed the association of ultrasound‐derived bone mineral density (UD‐BMD) with depressive symptoms in a population‐based study. We assessed the association of 30‐item Geriatric Depression Scale (GDS) score with the ultrasound‐derived T‐score, Z‐score, and Stiffness index in all 306 subjects aged 75 + living in Tuscania (Italy).

Results

In multivariable linear regression analysis, GDS was associated among men with the ultrasound‐derived T‐score (β = −0.09; 95% CI = −0.15 to −0.03; p = 0.003), Z‐score (β = −0.07; 95% CI = −0.13 to −0.01; p = 0.032), and the Stiffness index (β = −0.90; 95% CI = −1.64 to −0.16; p = 0.018) after adjusting for potential confounders. No significant associations were observed in women. In linear discriminant analysis, the GDS score cutoff that best predicted osteoporosis was ≥19. Participants with mild to severe depressive symptoms had threefold increased probability of having an ultrasound‐derived T‐score < −2.5.

Conclusions

Depressive symptoms are independently associated with all UD‐BMD parameters. As depression is a common feature among older populations, and because subjects with depression are infrequent users of preventive services, older men with depression should be prompted to undergo screening for osteoporosis. Conversely, assessment for depression should be performed in older men with diagnosis of osteoporosis. Copyright © 2008 John Wiley & Sons, Ltd.
Prevalence of depression and anxiety symptoms in elderly patients admitted in post‐acute intermediate care
Authors: Yohannes A. M. , Baldwin R. C. , Connolly M. J.
Published: May 2008

Objectives

Depression and anxiety symptoms are common in medically ill older patients. We investigated the prevalence and predictors of depression and anxiety symptoms in older patients admitted for further rehabilitation in post acute intermediate care.

Design

Observational cohort study.

Setting

An intermediate care unit, North West of England.

Participants

One hundred and seventy‐three older patients (60 male), aged mean (SD) 80 (8.1) years, referred for further rehabilitation to intermediate care.

Measurements

Depression and anxiety symptoms were assessed by the Hospital Anxiety and Depression Scale, and severity of depression examined by the Montgomery Asberg Depression Rating Scale. Physical disability was assessed by the Nottingham Extended ADL Scale and quality of life by the SF‐36.

Results

Sixty‐five patients (38%) were identified with depressive symptoms, 29 (17%) with clinical depression, 73 (43%) with anxiety symptoms, and 43 (25%) with clinical anxiety. 15 (35%) of the latter did not have elevated depression scores (9% of the sample). Of those with clinical depression, 14 (48%) were mildly depressed and 15 (52%) moderately depressed. Longer stay in the unit was predicted by severity of depression, physical disability, low cognition and living alone (total adjusted R2 = 0.24).

Conclusions

Clinical depression and anxiety are common in older patients admitted in intermediate care. Anxiety is often but not invariably secondary to depression and both should be screened for. Depression is an important modifiable factor affecting length of stay. The benefits of structured management programmes for anxiety and depression in patients admitted in intermediate care are worthy of evaluation. Copyright © 2008 John Wiley & Sons, Ltd.
A meta‐analytic study of changes in brain activation in depression
Authors: Fitzgerald Paul B. , Laird Angela R. , Maller Jerome , Daskalakis Zafiris J.
Published: May 2008

The article to which this erratum refers is published in this issue, Hum Brain Mapp (2008) 29:683–695. © 2008 Wiley‐Liss, Inc.
Optofluidic stretching of RBCs using single optical tweezers
Authors: Mohanty S. K. , Uppal A. , Gupta P. K.
Published: May 2008

Our previous studies demonstrated a huge difference in rotational speed of trapped red blood cells under diseased condition, which was presumably attributed to change in viscoelastic properties. Here, we report use of single optical tweezers combined with viscous drag for stretching of the trapped cell. Significant differences were observed in the measured viscoelastic parameters of fresh and aged/malaria‐infected RBCs under hypotonic condition. The technique was also found to provide information about adhesion properties of RBCs. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Oxidized low‐density lipoprotein acts synergistically with β‐glycerophosphate to induce osteoblast differentiation in primary cultures of vascular smooth muscle cells
Authors: Bear Mackenzie , Butcher Martin , Shaughnessy Stephen G.
Published: May 2008

Previous studies have localized osteoblast specific markers to sites of calcified atherosclerotic lesions. We therefore decided to use an established in vitro model of vascular calcification in order to confirm earlier reports of oxidized low‐density lipoprotein (oxLDL) promoting the osteogenic differentiation of vascular smooth muscle cells. Treatment of primary bovine aortic smooth muscle cells (BASMCs) with β‐glycerophosphate was found to induce a time‐dependent increase in osteoblast differentiation. In contrast, no effect was seen when BASMCs were cultured in the presence of oxLDL alone. However, when the BASMCs were cultured in the presence of both β‐glycerophosphate and oxLDL, β‐glycerophosphate's ability to induce osteoblast differentiation was significantly enhanced. In an attempt to resolve the mechanism by which this effect was occurring, we examined the effect of β‐glycerophosphate and oxLDL on several pathways known to be critical to the differentiation of osteoblasts. Surprisingly, β‐glycerophosphate alone was found to enhance Osterix (Osx) expression by inducing both Smad 1/5/8 activation and Runx2 expression. In contrast, oxLDL did not affect either Smad 1/5/8 activation or Runx2 activation but rather, it enhanced both β‐glycerophosphate‐induced Osx expression and osteoblast differentiation in an extracellular signal‐regulated kinase 1 and 2 (Erk 1 and 2) ‐dependent manner. When taken together, these findings suggest a plausible mechanism by which oxLDL may promote osteogenic differentiation and vascular calcification in vivo. J. Cell. Biochem. 105: 185–193, 2008. © 2008 Wiley‐Liss, Inc.
Mass transfer kinetics of neodymium(III) extraction by calix[4]arene carboxylic acid using a constant interfacial area cell with laminar flow
Authors: He Wenwei , Liao Wuping , Wang Weiwei , Li Deqian , Niu Chunji
Published: May 2008

BACKGROUND: Thermodynamics and kinetics data are both important to explain the extraction property. In order to develop a novel separation technology superior to current extraction systems, many promising extractants have been developed including calixarene carboxylic acids. The extraction thermodynamics behavior of calix[4]arene carboxylic acids has been reported extensively. In this study, the mass transfer kinetics of neodymium(III) and the interfacial behavior of calix[4]arene carboxylic acid were investigated.

RESULTS: The rate constant (Kao) becomes constant when the stirring speed was controlled between 250 rpm and 400 rpm. The activation energy (Ea) was calculated to be 21·41 kJ mol−1 or 88·17 kJ mol−1 (dependent on temperature) from the slope of log Kao against 1000/T. The linear relationship between the specific area and the extraction rate is the characteristic of an interfacial reaction control. The minimum bulk concentration of the extractant necessary to saturate the interface (Cmin) is lower than 4·19 × 10−4 mol L−1.

CONCLUSION: The effect of stirring speed, temperature, and species concentration on the extraction rate demonstrates that the extraction regime depends on the extraction conditions. The chemical reaction control governs the extraction regime at temperatures below 303 K and a mixed control regime occurs when the temperature is between 303 K and 318 K. The probable locale for the chemical reaction is at the liquid–liquid interface and the rate equation is deduced to be: − d[Nd3+](a)/dt = kf[Nd3+](a)[H4A](o)0·727[H+](a)−0·978. The rate‐controlling step was suggested by the analysis of the experimental results. Copyright © 2008 Society of Chemical Industry
Modeling and optimization of lipase‐catalyzed synthesis of dilauryl adipate ester by response surface methodology
Authors: Rahman Mohd Basyaruddin Abdul , Chaibakhsh Naz , Basri Mahiran , Rahman Raja Noor Zaliha Raja Abdul , Salleh Abu Bakar , Radzi Salina Md
Published: May 2008

BACKGROUND: Adipate esters are used as low‐temperature and low‐viscosity plasticizers for polyvinyl chloride and its copolymers. In this work, optimization of lipase‐catalyzed production of dilauryl adipate was carried out using response surface methodology (RSM) based on a four‐factor‐five‐level central composite rotatable design (CCRD). Immobilized lipase from Candida antarctica (Novozym 435) was used as catalyst in this reaction. Various reaction parameters affecting the synthesis of adipate ester, including alcohol/acid molar ratio, amount of enzyme, temperature and reaction time, were investigated.

RESULTS: Statistical analysis showed that the amount of enzyme was less significant than the other three factors. The optimal conditions for the enzymatic reaction were obtained at 5.7:1 substrate molar ratio using 0.18 g of enzyme at 53.1 °C for 282.2 min. Under these conditions the esterification percentage was 96.0%.

CONCLUSIONS: The results demonstrated that response surface methodology can be applied effectively to optimize the lipase‐catalyzed synthesis of adipate ester. The optimum conditions can obtained be used to scale up the process. Copyright © 2008 Society of Chemical Industry
Mixed‐mode hydrophilic interaction/cation‐exchange chromatography: Separation of complex mixtures of peptides of varying charge and hydrophobicity
Authors: Mant Colin T. , Hodges Robert S.
Published: May 2008

Mixed‐mode hydrophilic interaction/cation‐exchange chromatography (HILIC/CEX) was applied to the separation of two mixtures of synthetic peptide standards: (i) a 27‐peptide mixture containing three groups of peptides (each group containing nine peptides of the same net charge of +1, +2 or +3), where the hydrophilicity/hydrophobicity of adjacent peptides within the groups varied only subtly (generally by only a single carbon atom); and (ii) peptide pairs with the same composition but different sequences, where the sole difference between the peptides was the position of a single amino acid substitution. HILIC/CEX is essentially CEX chromatography in the presence of high levels of organic modifier (generally ACN). The present study demonstrated the dramatic effect of increasing ACN concentration (optimum levels of 60–80%, depending on the application) on the separation of both mixtures of peptides. The greater the charge on the peptides, the better the separation achievable by HILIC/CEX. In addition, HILIC/CEX separation of both the peptide mixtures used in the present study was shown to be superior to that of the more commonly applied RP‐HPLC mode. Our results highlight again the efficacy of HILIC/CEX as a peptide separation mode in its own right as well as an excellent complement to RP‐HPLC.
Method development for HILIC assays
Authors: Dejaegher Bieke , Mangelings Debby , Vander Heyden Yvan
Published: May 2008

In this review, method development for hydrophilic interaction LC (HILIC) is highlighted. HILIC is a chromatographic technique that uses aqueous‐organic solvent mobile phases with a high organic‐solvent fraction, and a hydrophilic stationary phase. It is mainly applied for the separation of polar and hydrophilic compounds. Method development, in general, can be done uni‐ or multivariately. In the univariate approach, the factors that are expected to potentially affect the separation of the compounds will be examined sequentially and one‐at‐a‐time. All HILIC methods found in the literature were developed in this way. For these methods, the analytes, the considered factors, the selected responses, and the finally chosen experimental conditions are discussed in this review. Where examined, the method validation and the comparison with other analytical assay methods is also described. For the multivariate method‐development approach, which is based on the use of experimental designs, only a possible strategy is presented, because of the lack of relevant publications in the literature.
Separation properties of novel and commercial polar stationary phases in hydrophilic interaction and reversed‐phase liquid chromatography mode
Authors: Wu JunYan , Bicker Wolfgang , Lindner Wolfgang
Published: May 2008

Four novel nonionic polar stationary phases were synthesised by anchoring first 2‐mercaptoethanol and 1‐thioglycerol, respectively, onto vinylised silica (ME and TG packings) followed by an on‐phase oxidation with excess hydrogen peroxide in aqueous medium which yielded sulphoxide analogues of the embedded sulphide groups, i. e. oxidised 2‐mercaptoethanol (MEO) and oxidised 1‐thioglycerol (TGO) packings. Chromatographic characteristics of these stationary phases were evaluated comparatively to three commercial so‐called ‘diol’ columns. U‐shaped response curves of retention factors of adenosine and guanosine with hydro‐organic eluents containing 5–95% v/v ACN as well as noticeable CH2‐increment selectivity demonstrated multimodal separation capabilities of the developed amphiphilic materials, i. e. columns can be operated both in hydrophilic interaction chromatography (HILIC) and in RP mode. Although the selector ligands were physico‐chemically related, considerably differing retention and selectivity patterns were observed in the HILIC mode. Thereby the introduction of additional hydroxyl groups in the chromatographic ligand resulted in selectivity increments that were different from those obtained by sulphur oxidation. For example, a set of five vitamins delivered five different elution orders with the overall seven columns. A close examination of HILIC separations of nucleobases and nucleosides on the developed packings revealed that (i) the amount of ACN in the eluent adopts a pivotal role in adjusting retention, (ii) the linearity of the relationship log (retention factor) versus log (volume fraction of water in the eluent) increases with phase polarity in the range of 5–40% v/v water, (iii) the slopes are higher with solutes having more polar interactive sites, (iv) the van't Hoff plots are linear (range 15–45°C) with negative retention enthalpy values ΔH (–4.5 to –14.5 kJ/mol) and (v) the –ΔH values tend to be higher with more polar phases and more polar analytes. Based on these data the HILIC retention mechanism is described to be composed of both partitioning and adsorption processes. Distinct types of polar interactive sites in the chromatographic ligands may generate mixed‐mode HILIC separation conditions that may additionally be superimposed by surface silanol contributions.
Fast hydrophilic interaction liquid chromatographic separations on bonded zwitterionic stationary phase
Authors: Appelblad Patrik , Jonsson Tobias , Jiang Wen , Irgum Knut
Published: May 2008

Separation science is an art of obtaining adequate resolution of the desired compounds in minimum time, and with minimum effort in terms of sample preparation and data evaluation. In LC, where selectivity is a main driving force for separation, the availability of different separation modes capable of operating at high flow rates is a way to make combined optimal use of selectivity, efficiency, and speed. The separation of polar and hydrophilic compounds is problematic in RP LC due to the poor retention. Hydrophilic interaction liquid chromatography (HILIC) is a more straightforward separation mode to address this problem. Herein, it is shown that separations in HILIC mode are equally efficient as for RP, providing a potential for very fast separations on short columns. This is not only facilitated by the low viscosity of the mobile phase compositions used, compared to typical RP eluents, but also due to higher column permeability. To exemplify this, baseline separations of uracil and cytosine are shown in less than 4 s and of Tamiflu® and its main metabolite in less than 40 s, both under isocratic conditions. HILIC must therefore be considered having potential for high throughput purposes, and being an attractive candidate as the second separation dimension in 2‐D HPLC.
Macromol. Biosci. 5/2008
Authors: Fan Jun , Li Yan , Jiang Hongliang , Tang Guping , Wang Liqun
Published: May 2008

Cover: The surface erosion process of poly{[di(p‐carboxyphenyl) succinate]‐co‐(sebacic anhydride)} can be directly visualized with fluorescent microscopy (as can be seen on the cover page), owing to its inherently fluorescent property and the fine correlation of the fluorescent intensity with its molecular weight. The unique luminescent characteristics of the polyanhydride, as well as its availability, biodegradability and histocompatibility, makes the polymer a promising candidate for a “visible” carrier for drug delivery. Further details can be found in the article by J. Fan, Y. Li, H. Jiang,* G. Tang, and L. Wang on page 384.
Phase Separation and Properties of UV‐Curable Polyurethane/Zirconia Nanocomposite Coatings
Authors: Zhou Shuxue , Wu Limin
Published: May 2008

Transparent zirconia (ZrO2) nanocrystal dispersions in butyl acetate (BAc) or tetrahydrofuran (THF) were prepared by functionalizing zirconia nanocrystals, synthesized from a solvothermal reaction of zirconium (IV) isopropoxide isopropyl alcohol complex in benzyl alcohol, with 3‐methacryloxypropyltrimethoxysilane (MPS), and were embedded into UV‐curable polyurethane (PU) coatings. It was found that the ZrO2 concentration was the dominating factor influencing the transparency of the ZrO2 dispersion, while the molar ratio of MPS to ZrO2 was rather efficient in adjusting the amount of MPS attached. Phase separation of the ZrO2 nanocrystals in polyurethane coatings was observed, and was strongly related to the MPS‐modified ZrO2 (MPS‐ZrO2) content and the amount of MPS chemically bonded. The phase separation of the PU/ZrO2 nanocomposite coatings appeared more seriously for higher MPS‐ZrO2 content and higher amounts of MPS attached; thus the transparency of the nanocomposite coatings was lower. However, completely transparent PU/ZrO2 nanocomposite coatings could be still achieved even with a ZrO2 content up to 7.5 wt.‐% using a ZrO2/BAc dispersion. Improvements in pendulum hardness, microhardness and scratch resistance of the polyurethane coatings via addition of MPS‐ZrO2 were demonstrated, but were not remarkable because of the low cross‐linking efficiency of the MPS‐ZrO2 nanoparticles resulting from the poor compatibility of the MPS‐ZrO2 nanoparticles with the pure PU oligomers.

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Characterizing PSPACE with pointers
Authors: Oitavem Isabel
Published: May 2008

This paper gives an implicit characterization of the class of functions computable in polynomial space by deterministic Turing machines – PSPACE. It gives an inductive characterization of PSPACE with no ad‐hoc initial functions and with only one recursion scheme. The main novelty of this characterization is the use of pointers (also called path information) to reach PSPACE. The presence of the pointers in the recursion on notation scheme is the main difference between this characterization of PSPACE and the well‐known Bellantoni‐Cook characterization of the polytime functions – PTIME. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ionized‐Air‐Treated Curaua Fibers as Reinforcement for Phenolic Matrices
Authors: Trindade Wanderson Gonçalves , de Paiva Jane Maria Faulstich , Leão Alcides Lopes , Frollini Elisabete
Published: May 2008

Curaua fibers were treated with ionized air to improve the fiber/phenolic matrix adhesion. The treatment with ionized air did not change the thermal stability of the fibers. The impact strength increased with increase in the fiber treatment time. SEM micrographs of the fibers showed that the ionized air treatment led to separation of the fiber bundles. Treatment for 12 h also caused a partial degradation of the fibers, which prompted the matrix to transfer the load to a poorer reinforcing agent during impact, thereby decreasing the impact strength of the related composite. The composites reinforced with fibers treated with ionized air absorbed less water than those reinforced with untreated fibers.

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Variational principles for symmetric bilinear forms
Authors: Danciger Jeffrey , Garcia Stephan Ramon , Putinar Mihai
Published: May 2008

Every compact symmetric bilinear form B on a complex Hilbert space produces, via an antilinear representing operator, a real spectrum consisting of a sequence decreasing to zero. We show that the most natural analog of Courant's minimax principle for B detects only the evenly indexed eigenvalues in this spectrum. We explain this phenomenon, analyze the extremal objects, and apply this general framework to the Friedrichs operator of a planar domain and to Toeplitz operators and their compressions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The stringy E‐function of the moduli space of Higgs bundles with trivial determinant
Authors: Kiem Young‐Hoon , Yoo Sang‐Bum
Published: May 2008

Let M be the moduli space of semistable rank 2 Higgs pairs (V, ϕ) with trivial determinant over a smooth projective curve X of genus g ≥ 2. We provide an explicit formula for the stringy E‐function of M. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrochemical Synthesis of Perfluorinated Ion Doped Conducting Polyaniline Films Consisting of Helical Fibers and their Reversible Switching between Superhydrophobicity and Superhydrophilicity
Authors: Xu Lianbin , Chen Zhongwei , Chen Wilfred , Mulchandani Ashok , Yan Yushan
Published: May 2008

Superhydrophobic conducting polyaniline (PAni) films were electrochemically deposited in acetonitrile‐H2O electrolyte containing aniline monomer and perfluorooctanesulfonic (PFOS) acid. The films exhibited an extended network structure composed of helical PAni sub‐micron fibers. The helical fibrous structure is thought to form through a supermolecular templating process. The surface of the PFOS‐doped PAni films showed a water contact angle of 153°. Reducing the PFOS‐doped PAni (in emeraldine salt form) by negative potential led to de‐doped PAni films (in leucoemeraldine base form) which were superhydrophilic (water contact angle close to 0°). By controlling the electrical potential, PAni films were changed between the doped state and de‐doped state, resulting in reversibly switchable superhydrophobic and superhydrophilic surfaces.

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Polyurethanes Containing Indole‐Based Non‐Linear Optical Chromophores: from Linear Chromophore to H‐Type
Authors: Li Qianqian , Yu Gui , Huang Jing , Liu Haijie , Li Zhen , Ye Cheng , Liu Yunqi , Qin Jingui
Published: May 2008

Two new “H” type of indole‐based chromophores were designed and successfully introduced to the polymeric system, the resultant polymers demonstrated enhanced NLO effects, good processability, thermal stability and nearly excellent transparency, indicating the advantages of “H” type chromophore moieties. And they could be promising candidates for the practical applications as new photonic materials.

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Strengthening Carbon Deposition of Polyolefin Using Combined Catalyst as a General Method for Improving Fire Retardancy
Authors: Song Rongjun , Jiang Zhiwei , Yu Haiou , Liu Jie , Zhang Zhijun , Wang Qingwen , Tang Tao
Published: May 2008

Combination of Ni2O3 and solid acid with Brønsted acid sites and Lewis acid sites (such as HZSM‐5 and H‐beta) could dramatically improve fire retardancy of polyolefin, including polypropylene and linear low‐density polyethylene. This is mainly attributed to the formation of a large amount of residual char from degradation products of polyolefin in the intermediate stage of combustion. Thus, the amount of flammable components diffusing into the flame zone was small. The investigation on the combined effect of solid acid and Ni2O3 showed that the presence of cationic reactive intermediates, mainly originating from Brønsted acid sites on the solid acid, strongly promoted carbon deposition of the degradation products. As a general method for improving fire retardancy of polyolefin, optimizing combination of metal catalyst and solid acid will further promote efficiency of fire retardancy.

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Hybrid Miniemulsion Polymerization of Acrylate/Oil and Acrylate/Fatty Acid Systems
Authors: Guo Juchen , Schork F. Joseph
Published: May 2008

Acrylate–alkyd hybrid latex via miniemulsion polymerizations show promise as water‐borne coating systems. However, poor homogeneity of the particles caused by the immiscibility of the alkyd in polyacrylate limits monomer conversion and film formation. To resolve this problem, the hybrid miniemulsion polymerization of acrylate in the presence of linoleic acid and sunflower seed oil was carried out. Products were characterized by solvent extraction, dynamic light scattering, gel permeation chromatography (GPC), differential scanning calorimeter (DSC), and transmission electron microscopy (TEM). The results provide clear evidence that substituting a fatty acid or natural oil with smaller molecular size (weight) for a conventional alkyd improves the grafting efficiency, and enhances the homogeneity of the hybrid polymer particles in water‐borne latex systems.

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In vivo brain viscoelastic properties measured by magnetic resonance elastography
Authors: Green Michael A. , Bilston Lynne E. , Sinkus Ralph
Published: May 2008

Magnetic resonance elastography (MRE) is a non‐invasive imaging technique used to visualise and quantify mechanical properties of tissue, providing information beyond what can be currently achieved with standard MR sequences and could, for instance, provide new insight into pathological processes in the brain. This study uses the MRE technique at 3 T to extract the complex shear modulus for in vivo brain tissue utilizing a full three‐dimensional approach to reconstruction, removing contributions of the dilatational wave by application of the curl operator. A calibrated phantom is used to benchmark the MRE measurements, and in vivo results are presented for healthy volunteers. The results provide data for in vivo brain storage modulus (G′), finding grey matter (3.1 kPa) to be significantly stiffer than white matter (2.7 kPa). The first in vivo loss modulus (G″) measurements show no significant difference between grey matter (2.5 kPa) and white matter (2.5 kPa). Copyright © 2008 John Wiley & Sons, Ltd.
EXTL3 promoter methylation down‐regulates EXTL3 and heparan sulphate expression in mucinous colorectal cancers
Authors: Karibe T , Fukui H , Sekikawa A , Shiratori K , Fujimori T
Published: May 2008

Exostoses like‐3 (EXTL3) is a putative tumour suppressor gene but its involvement in colorectal cancer (CRC) is unclear. We have investigated the role of methylation of the EXTL3 promoter as a mechanism for EXTL3 regulation and tested the hypothesis that loss of EXTL3 expression is associated with mucinous differentiation and alteration of glycoprotein expression in CRC cells. The methylation status of the EXTL3 gene promoter was analysed by methylation‐specific PCR following bisulphite modification in CRC cell lines and microdissected primary CRC tissues and their corresponding adjacent normal colorectal mucosa. EXTL3 promoter methylation was detected in seven of 11 mucinous CRCs (63.6%) but in none of 26 non‐mucinous CRCs examined. EXTL3 promoter methylation was also detected in the normal colonic mucosa of three patients with mucinous CRC but not in the normal colonic mucosa of any patients with non‐mucinous CRC. The presence of EXTL3 methylation was significantly associated with the partial loss of HS expression in mucinous CRC lesions. The mucinous CRC cell lines, Colo201 and Colo205, showed EXTL3 promoter methylation and loss of EXTL3 mRNA expression. However 5‐aza‐2′‐deoxycytidine treatment demethylated the EXTL3 gene promoter and restored its mRNA expression. Furthermore, the basal expression of HS in CRC cells was abolished by treatment with EXTL3‐siRNA. We conclude that EXTL3 promoter methylation and its related loss of EXTL3 expression are involved in the loss of HS expression in mucinous CRCs. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Stem cell factor as a novel diagnostic marker for early malignant germ cells
Authors: Stoop H , Honecker F , van de Geijn GJM , Gillis AJM , Cools MC , de Boer M , Bokemeyer C , Wolffenbuttel KP , Drop SLS , de Krijger RR , Dennis N , Summersgill B , McIntyre A , Shipley J , Oosterhuis JW , Looijenga LHJ
Published: May 2008

Carcinoma in situ (CIS) of the testis is the pre‐invasive stage of type II testicular germ cell tumours (TGCTs) of adolescents and adults. These tumours are the most frequently diagnosed cancer in Caucasian adolescents and young adults. In dysgenetic gonads, the precursor of type II GCTs can be either CIS or a lesion known as gonadoblastoma (GB). CIS/GB originates from a primordial germ cell (PGC)/gonocyte, ie an embryonic cell. CIS can be cured by local low‐dose irradiation, with limited side effects on hormonal function. Therefore, strategies for early diagnosis of CIS are essential. Various markers are informative to diagnose CIS in adult testis by immunohistochemistry, including c‐KIT, PLAP, AP‐2γ, NANOG, and POU5F1 (OCT3/4). OCT3/4 is the most informative and consistent in presence and expression level, resulting in intense nuclear staining. In the case of maturational delay of germ cells, frequently present in gonads of individuals at risk for type II (T)GCTs, use of these markers can result in overdiagnosis of malignant germ cells. This demonstrates the need for a more specific diagnostic marker to distinguish malignant germ cells from germ cells showing maturation delay. Here we report the novel finding that immunohistochemical detection of stem cell factor (SCF), the c‐KIT ligand, is informative in this context. This was demonstrated in over 400 cases of normal (fetal, neonatal, infantile, and adult) and pathological gonads, as well as TGCT‐derived cell lines, specifically in cases of CIS and GB. Both membrane‐bound and soluble SCF were expressed, suggestive of an autocrine loop. SCF immunohistochemistry can be a valuable diagnostic tool, in addition to OCT3/4, to screen for precursor lesions of TGCTs, especially in patients with germ cell maturation delay. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Human tumour clonality assessment—flawed but necessary
Authors: Leedham SJ , Wright NA
Published: May 2008

One of the premises of the somatic mutation theory of carcinogenesis is that tumours are clonal lesions derived from a single mutated stem cell progenitor. This theory spawned a proliferation of clonality studies, using a variety of different molecular markers to try to determine tumour clonality in multiple organs. In order to establish true clonality, it is necessary to identify the original founding mutation that occurred at the initiation of the progenitor clone. Use of other lesions may only serve to identify sub‐clones. As founding mutations have not been properly established in many organ systems, human clonality assessments carry this caveat. However it is only through clonality and mutation burden assessments that phylogenetic tress become established. Here, we review the advantages, disadvantages and use of different clonality markers. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Genetic loss of Gas6 induces plaque stability in experimental atherosclerosis
Authors: Lutgens E , Tjwa M , de Frutos P Garcia , Wijnands E , Beckers L , Dahlbäck B , Daemen MJAP , Carmeliet P , Moons L
Published: May 2008

The growth arrest‐specific gene 6 (Gas6) plays a role in pro‐atherogenic processes such as endothelial and leukocyte activation, smooth muscle cell migration and thrombosis, but its role in atherosclerosis remains uninvestigated. Here, we report that Gas6 is expressed in all stages of human and mouse atherosclerosis, in plaque endothelial cells, smooth muscle cells and macrophages. Gas6 expression is most abundant in lesions containing high amounts of macrophages, ie thin fibrous cap atheroma and ruptured plaque. Genetic loss of Gas6 does not affect the number and size of initial and advanced plaques in ApoE−/− mice, but alters its plaque composition. Compared to Gas6+/+: ApoE−/− mice, initial and advanced plaques of Gas6−/−: ApoE−/− mice contained more smooth muscle cells and more collagen and developed smaller lipid cores, while the expression of TGFβ was increased. In addition, fewer macrophages were found in advanced plaques of Gas6−/−: ApoE−/− mice. Hence, loss of Gas6 promotes the formation of more stable atherosclerotic lesions by increasing plaque fibrosis and by attenuating plaque inflammation. These findings identify a role for Gas6 in plaque composition and stability. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The report of posttraumatic growth in Malaysian cancer patients: relationships with psychological distress and coping strategies
Authors: Schroevers Maya J. , Teo Irene
Published: May 2008

Objective: The challenge of a cancer diagnosis may eventually lead to the experience of positive psychological changes, also referred to as posttraumatic growth. As most research on posttraumatic growth in cancer patients has been conducted in Western countries, little is known about the experience of such positive psychological changes in non‐Western countries. Therefore, the purpose of this cross‐sectional study was to investigate the prevalence of posttraumatic growth in a Malaysian sample of cancer patients. Secondly, we examined the association of posttraumatic growth with patients' report of psychological distress and their use of coping strategies.

Methods: The study was conducted in 113 cancer patients. Posttraumatic growth was measured by the Posttraumatic Growth Inventory, coping strategies by the brief COPE, and psychological distress by the Symptom Check List (SCL‐90‐R).

Results: Results showed that many patients reported posttraumatic growth, mostly in the domain of appreciation of life. As hypothesized, the experience of posttraumatic growth was not significantly related to the level of psychological distress. Findings indicated that greater use of the coping strategies instrumental support, positive reframing, and humor was associated with more posttraumatic growth.

Conclusion: Overall, this study suggests that posttraumatic growth is not only a Western phenomenon. Malaysian cancer patients show similar trends in the report of growth as well as in its correlates as their Western counterparts. Copyright © 2008 John Wiley & Sons, Ltd.
Depression screening using the Patient Health Questionnaire‐9 administered on a touch screen computer
Authors: Fann Jesse R. , Berry Donna L. , Wolpin Seth , Austin‐Seymour Mary , Bush Nigel , Halpenny Barbara , Lober William B. , McCorkle Ruth
Published: May 2008

Objective: To (1) evaluate the feasibility of touch screen depression screening in cancer patients using the Patient Health Questionnaire‐9 (PHQ‐9), (2) evaluate the construct validity of the PHQ‐9 using the touch screen modality, and (3) examine the prevalence and severity of depression using this screening modality.

Methods: The PHQ‐9 was placed in a web‐based survey within a study of the clinical impact of computerized symptom and quality of life screening. Patients in medical oncology, radiation oncology, and hematopoietic stem cell transplantation (HSCT) clinics used the program on a touch screen computer in waiting rooms prior to therapy (T1) and during therapy (T2). Responses of depressed mood or anhedonia (PHQ‐2 cardinal depression symptoms) triggered additional items. PHQ‐9 scores were provided to the oncology team in real time.

Results: Among 342 patients enrolled, 33 (9.6%) at T1 and 69 (20.2%) at T2 triggered the full PHQ‐9 by endorsing at least one cardinal symptom. Feasibility was high, with at least 97% completing the PHQ‐2 and at least 96% completing the PHQ‐9 when triggered and a mean completion time of about 2 min. The PHQ‐9 had good construct validity. Medical oncology patients had the highest percent of positive screens (12.9%) at T1, while HSCT patients had the highest percent (30.5%) at T2. Using this method, 21 (6.1%) at T1 and 54 (15.8%) at T2 of the total sample had moderate to severe depression.

Conclusions: The PHQ‐9 administered on a touch screen computer is feasible and provides valid depression data in a diverse cancer population. Copyright © 2008 John Wiley & Sons, Ltd.
Redox signalling in cardiovascular disease
Authors: Charles Rebecca L. , Eaton Philip
Published: May 2008

Oxidative stress has almost universally and unequivocally been implicated in the pathogenesis of all major diseases, including those of the cardiovascular system. Oxidative stress in cells and cardiovascular biology was once considered only in terms of injury, disease and dysfunction. However, it is now appreciated that oxidants are also produced in healthy tissues, and they function as signalling molecules transmitting information throughout the cell. Conversely, when cells move to a more reduced state, as can occur when oxygen is limiting, this can also result in alterations in the function of biomolecules and subsequently cells. At the centre of this ‘redox signalling’ are oxidoreductive chemical reactions involving oxidants or reductants post translationally modifying proteins. These structural alterations allow changes in cellular redox state to be coupled to alterations in cell function. In this review, we consider aspects of redox signalling in the cardiovascular system, focusing on the molecular basis of redox sensing by proteins and the array of post‐translational oxidative modifications that can occur. In addition, we discuss studies utilising proteomic methods to identify redox‐sensitive cardiac proteins, as well as those using this technology more broadly to assess redox signalling in cardiovascular disease.
Transition from thin gold layers to nano‐islands on TCO for catalyzing the growth of one‐dimensional nanostructures
Authors: Alet Pierre‐Jean , Eude Laurent , Palacin Serge , Cabarrocas Pere Roca i
Published: May 2008

The formation of gold islands on a transparent conductive oxide by annealing a thin evaporated layer is studied by SEM. The droplets of metal formed this way may catalyze the growth of nanowires or nanotubes to be used in opto‐electronic devices. The effect of the initial thickness (between 1 nm and 4 nm) and the annealing temperature (between 70 °C and 650 °C) is investigated. A qualitative description of the evolution is given and quantitative data are obtained by automated image analysis. Number density, area and effective diameter of the aggregates depend heavily on the initial thickness but very slightly on the annealing temperature. Three phenomena are considered to explain the evolution: interfacial stress due to mismatch in the linear expansion coefficient, Ostwald ripening and kinetic aggregation. By comparing the experimental size distributions to the theoretical ones, the relevance of the last two is discussed. As an application, the gold catalyzed CVD growth of silicon nanowires on zinc oxide is demonstrated. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)