bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two modes of ERK activation by TNF in keratinocytes: Different cellular outcomes and bi‐directional modulation by vitamin D
Authors: Ziv Ester , Rotem Carmela , Miodovnik Mor , Ravid Amiram , Koren Ruth 
Published: December 2007

AbstractInflammation, elicited in the skin following tissue damage or pathogen invasion, may become chronic with deleterious consequences. Tumor necrosis factor (TNF) is a key mediator of cutaneous inflammation and the keratinocyte an important protagonist of skin immunity. Calcitriol, the hormonally active vitamin D metabolite, and its analogs attenuate epidermal inflammation and inhibit the hyperproliferation of keratinocytes associated with the inflammatory disorder, psoriasis. Since activation of extracellular signal‐regulated kinase (ERK) promotes keratinocyte proliferation and mediates epidermal inflammation, we studied the effect of calcitriol on ERK activation in HaCaT keratinocytes exposed to the ubiquitous inflammatory cytokine TNF. By using the EGF receptor (EGFR) tyrosine kinase inhibitor, AG1487 and the Src family inhibitor, PP‐1, we established that TNF activated ERK in an EGFR and Src dependent and an EGFR and Src independent modes. EGFR dependent activation resulted in the upregulation of the transcription factor, c‐Fos, while the EGFR independent activation mode was of a shorter duration, did not affect c‐Fos expression but induced IL‐8 mRNA expression. Pretreatment with calcitriol, enhanced TNF‐induced EGFR‐Src dependent ERK activation and tyrosine phosphorylation of the EGFR, but abolished the EGFR‐Src independent ERK activation. These effects were mirrored by enhancement of c‐Fos and inhibition of IL‐8 induction by TNF. Treatment with calcitriol increased the rate of the de‐phosphorylation of activated ERK, accounting for the inhibition of EGFR‐Src independent ERK activation by TNF. It is possible that effects on the ERK cascade contribute to the effects of calcitriol and its synthetic analogs on cutaneous inflammation and keratinocyte proliferation. J. Cell. Biochem. 104: 606–619, 2008. © 2007 Wiley‐Liss, Inc.
Prediction of the effects of imperfect construction of a QMS filter
Authors: Taylor Stephen , Gibson John R. 
Published: December 2007

AbstractModelling techniques have previously predicted the observed behaviour of perfectly manufactured QMS mass filters. These methods are extended to examination of the behaviour of imperfect QMS filters; this examination considers the behaviour of QMS filters with one rod displaced radially inward as this is a simple manufacturing defect that arises when a rod does not fit correctly into the mounting.The results demonstrate the well known, but poorly documented property, that exchanging the connections of a poorly performing QMS device sometimes improves performance. This is shown to arise because only a displacement of a y‐rod produces a large effect. The results also show that displacement of a y‐rod may produce a spurious additional peak known as a precursor. More detailed investigation suggests that precursors are not separate peaks but are formed because a section of the main peak is removed causing an apparent double peak.Finally results confirm that adjustment of the voltage applied to a displaced rod can be used to significantly improve the QMS behaviour. A small change by a fraction α in the position of a single rod may be compensated by a change of 2 × α in the voltage applied to that rod. Copyright © 2007 John Wiley & Sons, Ltd.
An efficient method for dephosphorylation of phosphopeptides by cerium oxide
Authors: Tan Feng , Zhang Yangjun , Wang Jinglan , Wei Junying , Cai Yun , Qian Xiaohong 
Published: December 2007

AbstractIn this article, an effective method for dephosphorylation of phosphopeptides by cerium oxide is described. The dephosphorylation activity of cerium oxide was evaluated by two standard phosphopeptides and the phosphopeptides in digests of phosphoprotein α‐casein and β‐casein. Results showed that the dephosphorylation of all the phosphopeptides was completed in 10 min, and temperature had little effect on the dephosphorylation, the dephosphorylation could be carried out at 0 °C, room temperature and 37 °C. The dephosphorylation mediated by cerium oxide can be attributed to Lewis acid and nucleophile activations. Advantages of using cerium oxide as catalyst for the dephosphorylation include: safe, simple, high catalytic activity, and no precise control of the treatment temperature. The method is valid for the phosphorylation of Ser, Thr and Tyr, and can be used for phosphoprotein analysis. Copyright © 2007 John Wiley & Sons, Ltd.
Neuroserpin regulates N‐cadherin‐mediated cell adhesion independently of its activity as an inhibitor of tissue plasminogen activator
Authors: Lee Tet Woo , Coates Leigh C. , Birch Nigel P. 
Published: December 2007

AbstractNeuroserpin is an inhibitor of tissue plasminogen activator (tPA) that is expressed in developing and adult nervous systems. Spatial and temporal analysis of neuroserpin expression suggests that it is involved in regulating the proteolytic balance associated with axonogenesis and synaptogenesis during development and synaptic plasticity in the adult. Here we demonstrate that altered expression of neuroserpin modulates the degree of cell–cell adhesion in pheochromocytoma PC12 cells independently of its role as an inhibitor of tPA. Levels of the homophilic cell–cell adhesion molecule N‐cadherin are increased in neuroserpin‐overexpressing cell lines. N‐cadherin immunoreactivity was detected in a Triton X‐100‐insoluble fraction and localized to regions of cell contact, consistent with a role in enhancing cell surface adhesion. PC12 cell lines expressing neuroserpin mutants that lack tPA inhibitory activity also showed increased cell–cell adhesion and N‐cadherin expression. Our results identify neuroserpin as a novel regulator of cell–cell adhesion and the synaptic adhesion molecule N‐cadherin as a key effecter in this response. In nerve cells, neuroserpin may regulate the levels of N‐cadherin available for construction, maintenance, and control of synapses and synaptic dynamics. © 2007 Wiley‐Liss, Inc.
Screening of phenylalanine ammonia lyase in plant tissues, and retention of activity during dehydration
Authors: Goldson Andrea , Lam Melanie , Scaman Christine H , Clemens Sabine , Kermode Allison 
Published: December 2007

AbstractBACKGROUND: Oral therapy with phenylalanine ammonia lyase (PAL), naturally encapsulated in plant cells, may provide a potential alternative treatment for hyperphenylalaninemic patients, including those with phenylketonuria. Therefore different sources of plant tissue were investigated for PAL activity.RESULTS: Enzyme activity was highest in grain seedlings, with maximal enzyme activity in 7‐day‐old red spring wheat (Triticum aestivum L.) seedlings. The PAL activities of leaves and roots/endosperm of wheat seedlings were 11.90 ± 2.64 and 6.48 ± 1.59 µmol h−1 g−1 dry weight respectively. Three PAL‐related polypeptides with molecular weights of 74, 83 and 103 kDa were identified in wheat seedling leaf tissues, while only the 74 kDa polypeptide was detected in root/endosperm tissues. Dehydration was investigated as a method of concentrating PAL in wheat seedlings. Freeze‐drying was found to retain the most PAL activity (>90% recovery on a dry weight basis) compared with air drying and vacuum microwave drying for both leaf and root/endosperm samples.CONCLUSION: This study has led to a better understanding of PAL activity and stability in plant tissues and provides the basis for developing a natural plant preparation as a dietary supplement for the treatment of hyperphenylalaninemia. Copyright © 2007 Society of Chemical Industry
Rats show differences in some biomarkers of health when eating diets based on ingredients produced with three different cultivation strategies
Authors: Lauridsen Charlotte , Yong Chen , Halekoh Ulrich , Bügel Susanne Højbjerg , Brandt Kirsten , Christensen Lars Porskjær , Jørgensen Henry 
Published: December 2007

AbstractBACKGROUND: The aim of this study was to identify health‐related biomarkers affected by different growth conditions of plant foods. Rats were fed balanced diets composed of vegetables and rapeseed oil from three different cultivation systems (‘LIminusP’, low fertiliser input, without pesticides; ‘LIplusP’, low fertiliser input, with pesticides; and ‘HIplusP’, high fertiliser input, with pesticides) chosen to cover a broad range of management options, rather than representing actual food production systems.RESULTS: Rats fed LIminusP and LIplusP had a higher serum IgG concentration compared to rats fed HIplusP and 14% less adipose tissue. Rats fed LIminusP showed less movement during the day than the other treatments, with no differences during the night. The liver metabolic function and free malonedialdehyde concentration differed between the LIminusP and the LIplusP treatments. Despite similar fatty acid composition and vitamin E content of the rapeseed oil used for the LIminusP and HIplusP diets, plasma concentrations of oleic and linoleic acids, γ‐ and α‐tocopherol and the liver concentration of lipid hydroperoxides differed between these two treatments.CONCLUSION: Differences between dietary treatments composed of ingredients from different cultivation methods caused differences in some health‐related biomarkers, which, in future studies on this topic, should be assessed with respect to health implications. Copyright © 2007 Society of Chemical Industry
Chemical stability of haloperidol injection by high performance thin‐layer chromatography
Authors: Mennickent Sigrid , Pino Loreto , Vega Mario , de Diego Marta 
Published: December 2007

AbstractThe chemical stability of haloperidol lactate injection was studied under different storage conditions by high performance thin‐layer chromatography (HPTLC). The study was performed at 25 ± 2°C and at refrigeration temperature (8 ± 1°C) in original glass ampoules over 15 days after being opened. The samples tested at 25 ± 2°C were stored with exposure to and protection from light. Chromatographic separation was achieved on precoated silica gel F 254 HPTLC plates using a mixture of acetone/chloroform/n‐butanol/glacial acetic acid/water (5:10:10:2.5:2.5, v/v/v/v/v) as a mobile phase. Quantitative analyses were carried out at a wavelength of 254 nm. The method exhibited adequate linearity (r = 0.999), selectivity, precision (RSD = 1.92%), and accuracy (recoveries from 98.59 to 101.90%). The concentrations of all samples remained greater than or 90% of the original concentration. Haloperidol lactate injection was chemically stable under all conditions studied over 15 days.
Nanocellular Foams of PS/PMMA Polymer Blends
Authors: Otsuka Tetsuo , Taki Kentaro , Ohshima Masahiro 
Published: December 2007

AbstractA nanocellular PS/PMMA polymer blend foam was prepared, where bubble nucleation was localized in the PMMA domains. The blend, which contains dispersed nanoscale PMMA islands, was prepared by polymerizing MMA monomers in a PS matrix to form highly dispersed PMMA domains in the PS matrix by diffusion mixing. The resulting blend was foamed with CO2 at room temperature. A higher depressurization rate at lower foaming temperature made the bubble diameter smaller and the bubble density larger, and a higher PS composition in the blend resulted in a larger bubble density. A void with 40–50 nm in average diameter and a pore density of 8.5 × 1014 cm−3 was obtained as for the finest nanocellular foams.magnified image
Flavonoids as RTK inhibitors and potential anticancer agents
Authors: Teillet Florence , Boumendjel Ahcene , Boutonnat Jean , Ronot Xavier 
Published: December 2007

AbstractTyrosine kinase receptors (RTKs) play a crucial role in the regulation of the cell division cycle. Currently more than 50 RTKs divided into several subfamilies have been described. The inhibition of these enzymes has emerged as an important research‐area. Compounds able to inhibit the activity of these enzymes are expected to display antiproliferative properties. Flavonoids are representative of various small molecules acting as RTK inhibitors. These naturally occurring compounds are able to bind to the ATP‐binding site of several kinases. The most plausible current hypothesis explaining the action of these substances on kinases is that the chromenone moiety of the flavonoid acts as a mimetic of the adenine moiety of ATP, the receptor co‐factor. In this review, we report recent results on the activity of natural and synthetic derivatives of flavonoids as inhibitors of RTKs. Mechanistic aspects, the therapeutic usefulness, and the potential clinical use are discussed. © 2007 Wiley Periodicals, Inc. Med Res Rev, 28, No. 5, 715–745, 2008
Global stability and the Hopf bifurcation for some class of delay differential equation
Authors: Bodnar Marek , Foryś Urszula 
Published: December 2007

AbstractIn this paper, we present an analysis for the class of delay differential equations with one discrete delay and the right‐hand side depending only on the past. We extend the results from paper by U. Foryś (Appl. Math. Lett. 2004; 17(5):581–584), where the right‐hand side is a unimodal function. In the performed analysis, we state more general conditions for global stability of the positive steady state and propose some conditions for the stable Hopf bifurcation occurring when this steady state looses stability. We illustrate the analysis by biological examples coming from the population dynamics. Copyright © 2007 John Wiley & Sons, Ltd.
Existence theorem and blow‐up criterion of the strong solutions to the magneto‐micropolar fluid equations
Authors: Yuan Jia 
Published: December 2007

AbstractIn this paper we study the magneto‐micropolar fluid equations in ℝ3, prove the existence of the strong solution with initial data inHs(ℝ3) for$s>{3\over2}$, and set up its blow‐up criterion. The tool we mainly use is Littlewood–Paley decomposition, by which we obtain a Beale–Kato–Majda‐type blow‐up criterion for smooth solution (u, ω,b) that relies on the vorticity of velocity ∇ × uonly. Copyright © 2007 John Wiley & Sons, Ltd.
The play operator on the rectifiable curves in a Hilbert space
Authors: Recupero Vincenzo 
Published: December 2007

AbstractThe vector play operator is the solution operator of a class of evolution variational inequalities arising in continuum mechanics. For regular data, the existence of solutions is easily obtained from general results on maximal monotone operators. If the datum is a continuous function of bounded variation, then the existence of a weak solution is usually proved by means of a time discretization procedure. In this paper we give a short proof of the existence of the play operator on rectifiable curves making use of basic facts of measure theory. We also drop the separability assumptions usually made by other authors. Copyright © 2007 John Wiley & Sons, Ltd.
A note on extinction for fast diffusive p‐Laplacian with sources
Authors: Liu Wenjun , Wu Bin 
Published: December 2007

AbstractIn this note we illuminate that the small condition on initial data u0 in Theorem 4.1 of Yin and Jin (Math. Meth. Appl. Sci. 2007; 30(10):1147–1167) can be removed for the case p−1<q<1. Precise decay estimates of solution are also obtained. Copyright © 2007 John Wiley & Sons, Ltd.
Correlations of dietary patterns with prostate health
Authors: Stacewicz‐Sapuntzakis Maria , Borthakur Gayatri , Burns James L. , Bowen Phyllis E. 
Published: December 2007

AbstractBoth genetic and environmental influences may be involved in etiology of prostate health and prostate cancer. These include ethnic origin, family history, smoking, and diet. Adiposity and excess energy intake are potentially distinct risk factors and positive associations with prostate cancer risk for both were observed among case‐control and cohort studies. Some epidemiological studies support an association between dietary fat, particularly saturated or animal fats, and prostate cancer risk. Of these, several suggest reduced risk with low‐fat diets high in n‐3 fatty acids and increased risk with high‐fat diets rich in n‐6 fatty acids. Others suggested association with higher meat intake, possibly due to heterocyclic amines and polycyclic aromatic hydrocarbons, produced during grilling or frying. Positive association of prostate cancer risk with dairy intake could involve α‐methylacyl‐CoA racemase activity (required for β‐oxidation of phytanic acid present in dairy products and red meat) or the suppression of vitamin D activity by calcium. Inverse associations were observed with dietary intake of plant foods. These include cereals, soy products, and fruit and vegetable sources of carotenoids. Numerous plant constituents may act synergistically in the prevention and inhibition of prostate disorders. These diet‐risk associations may lead to future individualized diet recommendations based upon genetic polymorphisms.
Effect of muscle‐fiber velocity recovery function on motor unit action potential properties in voluntary contractions
Authors: Farina Dario , Falla Deborah 
Published: December 2007

AbstractMeasurements of muscle‐fiber conduction velocity during voluntary contractions have been used in the diagnosis of neuromuscular diseases. However, the velocity of propagation of action potentials depends on the interspike interval of activation due to the velocity recovery function (VRF) of muscle fibers. The comparison of muscle‐fiber conduction velocity estimates between individuals may thus be influenced by differences in motor unit discharge rate. This study investigates action potential properties of motor units of the sternocleidomastoid muscle during voluntary modulation of discharge rate with the purpose of assessing the effect of the VRF on motor unit properties in voluntary contractions. Nineteen healthy men trained to control a target motor unit with feedback of surface multichannel electromyographic (EMG) signals. The subjects performed three 30‐s contractions of cervical flexion/rotation modulating the discharge rate of the target motor unit from 6.6 ± 1.6 pps to 28.0 ± 6.4 pps. Action potential conduction velocity was correlated to instantaneous discharge rate (R = 0.38 ± 0.21). Action potential conduction velocity, peak‐to‐peak amplitude, and duration varied between minimum and maximum discharge rate (P < 0.01; percent change 12.3 ± 5.0, −11.8 ± 9.9, and −12.9 ± 7.3). Thus, the properties of surface motor unit action potentials vary with modulation of discharge rate. This has implications for the use of conduction velocity values measured during voluntary contractions to differentiate patient populations from healthy individuals and for the development of normative data. Muscle Nerve, 2008
A rotation‐free corotational plane beam element for non‐linear analyses
Authors: Battini Jean‐Marc 
Published: December 2007

AbstractThis paper presents a plane beam element without rotational degrees of freedom that can be used for the analysis of non‐linear problems. The element is based on two main ideas. First, a corotational approach is adopted, which means that the kinematics of the element is decomposed into a rigid body motion part and a deformational part. Next, in the deformational part, the local nodal rotations are extrapolated as a function of the local displacements of the two nodes of the element and the first nodes to the left and right of the element. Six numerical applications are presented in order to assess the performance of the formulation. Copyright © 2007 John Wiley & Sons, Ltd.
Preparation and electro‐optic properties of novel Y‐type polyimides with highly enhanced thermal stability of second harmonic generation
Authors: Jung Won‐Taek , Lee Ju‐Yeon , Won Dong‐Seon , Rhee Bum Ku 
Published: December 2007

AbstractBACKGROUND: In the development of nonlinear optical (NLO) polymers for electro‐optic device applications, stabilization of electrically induced dipole alignment is one of the important criteria. Polyimides for NLO applications have attracted attention because of their high Tg values and high thermal stability. In this work we designed and synthesized a new type of NLO polyimide, in which the pendant NLO chromophores are parts of the polymer backbone. These mid‐type NLO polymers are expected to have the merits of both main‐chain and side‐chain NLO polymers: stabilization of dipole alignment and good solubility.RESULTS: 3,4‐Bis‐(3,4‐dicarboxyphenylcarboxyethoxy)‐4′‐nitrostilbene dianhydride was prepared and reacted with the corresponding aromatic diamine to yield unprecedented Y‐type polyimides containing 3,4‐dioxynitrostilbenyl groups as NLO chromophores, which constituted parts of the polymer backbones. The resulting polyimides are soluble in polar solvents such as dimethylformamide and dimethylsulfoxide. These polymers showed a thermal stability up to 320 °C in thermogravimetric thermograms with Tg values obtained from differential scanning calorimetry thermograms in the range 143–164 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at the 1064 nm−1 fundamental wavelength were around 9.45 × 10−18 C.CONCLUSION: The dipole alignment exhibited exceptionally high thermal stability even at 30 °C higher than Tg. There was no SHG decay below 180–190 °C because of the partial main‐chain character of the polymer structure, which is acceptable for NLO device applications. Copyright © 2007 Society of Chemical Industry
Understanding excitons in optically active polymers
Authors: Kirova Natasha 
Published: December 2007

AbstractWe review the solid‐state physics approach to electronic and optical properties of conducting polymers, and bring together the languages of solid‐state theory for polymers and the quantum chemistry of oligomers. We consider polymers as generic one‐dimensional semiconductors with specific features of strongly correlated electronic systems. Our model combines the large distance electron–hole motion within an exciton, governed by long‐range Coulomb attraction with strong intramonomer electronic correlations, which results in effective intramonomer electron–hole repulsion. We exploit the dielectric screening to go beyond the single chain picture and to compare excitons for polymers in solutions and in films. Our approach allows the connecting, explaining, exploiting and organizing of such different experimental and numerical findings as shallow singlet and deep triplet excitons in phenylenes, anomaly in singlet–triplet exciton formation ratio, Ag–Bu crossing in polyenes and common 1/N energy dependencies in oligomers. Copyright © 2007 Society of Chemical Industry