bluuebunny/crossref_metadata_2025 huggingface dataset:
Redox‐Active 17‐ and 19‐Membered Metallamacrocycles Incorporating Tetrathiafulvalene
Authors: Gachot Grégory , Pellon Pascal , Roisnel Thierry , Lorcy Dominique
Published: May 2006

Redox‐active 17‐ and 19‐membered metallamacrocycles were prepared thanks to the chelating ability of bis[(diphenylphosphane)alkylthio]TTF towards the M(CO)4 fragment(M = Mo, W). The TTF unit can adopt either a cis or a trans configuration as can the phosphorus atoms coordinated to the metal center. Moreover, an element of planar chirality is generated by the trans isomer of the TTF. Thus, the reaction affords six stereoisomers as evidenced by 31P NMR and X‐ray crystallographic analyses. The electrochemical properties of the title compounds have been investigated by cyclic voltammetry. Within the 19‐membered metallamacrocycles, no significant influence of the two redox moieties was detected, whereas in the 17‐membered metallamacrocycles, the oxidized TTF modifies the redox behavior of the metal center. Two crystalline complexes obtained with tetracyanoquinodimethane (TCNQ) and the tungsten 17‐ and 19‐membered metallamacrocycles are reported. Comparison of the crystal structures shows that these metallamacrocycles appear to be rather flexible even with strained structures.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A TTF–TCNQ Electrode as a Voltammetric Analogue of an Ion‐Selective Electrode
Authors: Cano Manuel , Palenzuela Beatriz , Rodríguez‐Amaro Rafael
Published: May 2006

A TTF‐TCNQ/PVC composite electrode is proposed as a voltammetric cation and anion sensor. The electrode relies on the principle that, during redox processes involving the TCNQ0/− couple for cations and the TTF+/0 couple for anions, electrolyte ions are included into lattice sites in the charge neutralization process. This voltammetric ion‐sensor provides results that are similar to those of sensors based on two electrodes (viz. one modified with TCNQ for cations and another modified with TTF for anions) but with some practical advantages over them.
Contribution to studies on calculation of the magnetic field under power lines
Authors: Budnik K. , Machczyński W.
Published: May 2006

The paper presents in a tutorial manner a theoretical study of the calculation of magnetic fields in vicinity of overhead electric power lines. Exact and simplified methods of the determination of the magnetic field of a straight overhead conductor based on the Fourier transform technique and on the concept of complex ground return plane are presented. The decomposition of the magnetic fields in two components: magnetic field obtained in free space from the Biot‐Savart law and the magnetic field produced by earth current is discussed. It is shown that in practical cases the effects from earth currents can be neglected as compared with effects from line currents. A solution for modeling magnetic fields produced by sagging conductor, described by the catenary equation, is also proposed. The effect of the catenary on the magnetic field spatial distribution is investigated. The calculation results of magnetic field produced by sagging conductor and the magnetic field of a conventional model consisting of a horizontal conductor hanging on the effective height lying between the maximum and minimum heights of catenaries is compared and discussed. As an example the magnetic field of a real‐power catenary high voltage 2 × 220 kV power line is demonstrated. Copyright © 2006 John Wiley & Sons, Ltd.
Survivin in esophageal cancer: An accurate prognostic marker for squamous cell carcinoma but not adenocarcinoma
Authors: Rosato Antonio , Pivetta Michela , Parenti Anna , Iaderosa Gaetano A. , Zoso Alessia , Milan Gabriella , Mandruzzato Susanna , Bianco Paola Del , Ruol Alberto , Zaninotto Giovanni , Zanovello Paola
Published: May 2006

We quantified the expression of survivin, both as mRNA in real‐time PCR and protein in immunohistochemistry, in tumor samples of 112 patients with esophageal cancer (56 squamous cell carcinomas and 56 adenocarcinomas). Overall survival of squamous cell carcinoma patients with high survivin mRNA levels was significantly less than that of patients with low survivin mRNA levels (p = 0.0033). Distribution pattern of survivin (nuclear vs. cytoplasmic or mixed) was not correlated to survival, while the extent of immunostaining was significantly correlated to survivin mRNA values (p = 0.016) and had prognostic relevance in univariate analysis (p = 0.0012). Cox's proportional‐hazard regression model showed that tumor survivin expression in esophageal squamous cell carcinoma was the most important prognostic factor, independent of tumor stage and other histopathological factors, both as mRNA relative value (p = 0.0259) and protein immunostaining (p = 0.0147). In esophageal adenocarcinoma, survivin expression and pattern of distribution had no prognostic relevance. Thus, quantifying survivin expression provides a prognostic marker only for esophageal squamous tumors. © 2006 Wiley‐Liss, Inc.
NNK activates ERK1/2 and CREB/ATF‐1 via β‐1‐AR and EGFR signaling in human lung adenocarcinoma and small airway epithelial cells
Authors: E. Laag , M. Majidi , M. Cekanova , T. Masi , T. Takahashi , H.M. Schuller
Published: May 2006

We have shown that the tobacco nitrosamine 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone (NNK) is an agonist for β‐adrenergic receptors (β‐ARs) and increased DNA synthesis of human lung adenocarinoma cells with features of bronchiolar Clara cells by binding to these receptors. Using a cell line derived from a human pulmonary adenocarcinoma with Clara cell phenotype (PACC) and immortalized human small airway epithelial cells (HPLD1), the putative cells of origin of this cancer type, our current studies have analyzed signaling initiated by binding of NNK to the β1‐AR. NNK upregulated ERK1/2 and CREB/ATF‐1 phosphorylation in a PKA‐dependent manner in both cell lines. This response was further increased by transient overexpression of the β1‐AR. Pre‐exposure of cells to the selective β1‐AR antagonist, atenolol, attenuated the stimulatory effects of NNK, suggesting the latter upregulated ERK1/2 and CREB/ATF‐1 via this receptor. In vivo labeling and immunoprecipitation assays revealed that NNK phosphorylated the epidermal growth factor receptor (EGFR) at tyrosine residues, 991, 1068 and 1173, an effect inhibited by atenolol. The inhibitor of EGFR‐specific tyrosine kinases, AG1478, reduced NNK ability to stimulate ERK1/2 and CREB/ATF‐1. Genomic analysis of the exons 18–21 of the EGFR genes showed that no mutations were present in either gene. Collectively, our data provide evidence, for the first time, that NNK targets ERK1/2 and CREB/ATF‐1 proteins via dual signaling involving β1‐AR and EGFR pathways in PACCs and their putative cells of origin. © 2006 Wiley‐Liss, Inc.
Chemokines and cancer
Authors: Zlotnik Albert
Published: May 2006

The chemokines and their receptors are a superfamily of small secreted molecules that control the migration of many cell types in the body. Several years ago it became clear that some chemokines and receptors regulate the migration of certain cells in the lymphoid system, and this raised the possibility that chemokines could also control the migration of tumor cells in the body. Breast cancer cells were found to express chemokine receptors in a nonrandom manner, and these observations pointed to several chemokine/receptor pairs that control tumor‐cell migration. The most important ligand/receptors pairs in these phenomena include CXCL12/CXCR4 and CCL21/CCR7. Since then, there has been intense interest in this area and many studies have been published, especially on CXCR4. These studies point to the following conclusions: (i) Tumors express chemokine receptors in a nonrandom manner. (ii) CXCR4 is the most widely expressed chemokine receptor in many different cancers. (iii) CCR7 is also expressed by many cancers, and is likely to mediate metastasis to the lymph nodes in selected cancers. (iv) The effects of CXCL12 on CXCR4‐bearing tumor cells likely include many other functions (growth, differentiation) besides migration. During normal development, the interaction CXCL12/CXCR4 is known to be involved in organogenesis. This process shares many characteristics with metastasis, and represents one of the key areas of future research. © 2006 Wiley‐Liss, Inc.
Methotrexate resistance in vitro is achieved by a dynamic selectionprocess of tumor cell variants emerging during treatment
Authors: de Anta Josep M. , Mayo Clara , Solé Francesc , Salido Marta , Espinet Blanca , Corzo Cristina , Petzold Myriam , Villa Olaya , Serrano Sergi , Real Francisco X. , Mayol Xavier
Published: May 2006

Genetic instability leads to tumor heterogeneity, which in turn provides a source of cell variants responsible for drug resistance. However, the source of resistant cells during the process of acquired resistance is poorly understood. Our aim has been to characterize the mechanism by which acquired resistance to methotrexate emerges during the course of cancer cell treatment in vitro. We recently demonstrated that, in vitro, HT‐29 colon cancer cells become transiently sensitive to methotrexate by depleting the extracellular milieu of survival factors; on the other hand, the cell population under treatment can reversibly adapt to grow below a critical cell density in the presence of the drug. Here, we show that this adapted cell population gives rise to permanent resistant populations through repeated cycles of cell death and growth. This increased cell turnover, but not merely cell proliferation, is required for the appearance of increasing degrees of stable resistance that are progressively selected by drug pressure. Such a process, taking place in multiple steps, is here designated “dynamic selection.” The analysis of sensitive and resistant HT‐29 cell populations revealed that methotrexate induces genomic instability—characterized by centrosome amplification and aberrant chromosome recombination—leading to a low‐level amplification of the 5q chromosome arm as one of the earliest genetic events selected during treatment. Therefore, this model provides a mechanism by which a tumor cell population lacking resistant subpopulations before treatment is able to acquire the genetic changes required for stable drug resistance. © 2006 Wiley‐Liss, Inc.
Regulation of lipocalin‐2 gene by the cancer chemopreventive retinoid 4‐HPR
Authors: Caramuta Stefano , De Cecco Loris , Reid James F. , Zannini Laura , Gariboldi Manuela , Kjeldsen Lars , Pierotti Marco A. , Delia Domenico
Published: May 2006

N‐(4‐Hydroxyphenyl)retinamide (4‐HPR) is a nonclassical retinoid with cancer preventive effectsin vivoand antiproliferative and apoptotic activitiesin vitro. Examining the transcriptional profile of human breast cancer cell lines, MCF7 and T47D, treated with 4‐HPR, we identified the lipocalin memberLCN2(NGALor24p3) as a gene, markedly induced by the retinoid. Because of its presumed function in apoptosis,LCN2was examined more thoroughly in response to 4‐HPR. Like mRNA, the expression of LCN2 protein in MCF7 and T47D cells was highly induced in a time‐dependent manner by 4‐HPR, but not by its inactive metabolite 4‐MPR and, to some extent, this event was linked to the free radicals normally generated by 4‐HPR. All‐trans retinoic acid also induced LCN2 protein, particularly in T47D cells. Ectopic LCN2 compromised cell viability, and the few MCF7 clones that survived LCN2 overexpression were less sensitive than do mock cells to 4HPR, indicating that selective pressure for survival to LCN2 confers cross‐resistance to 4‐HPR. Significantly, ablation of LCN2 induction by siRNA did not modify the response to 4‐HPR, implying that LCN2 is not critical for apoptosis by 4‐HPR. Our results indicate that 4‐HPR markedly induces LCN2 expression, but this event may not represent an apoptotic response. © 2006 Wiley‐Liss, Inc.
Inhibition of connective tissue growth factor by siRNA prevents liver fibrosis in rats
Authors: Li Guangming , Xie Qing , Shi Yi , Li Dingguo , Zhang Mingjun , Jiang Shan , Zhou Huijuan , Lu Hanming , Jin Youxin
Published: May 2006

Background

Connective tissue growth factor (CTGF) is a highly profibrogenic molecule implicated in hepatic fibrogenesis. Small interfering RNA (siRNA) is an effective tool to silence gene expression post‐transcriptionally. Therefore, we conducted an investigation to determine if intraportal vein siRNA injection targeting CTGF inhibits CTGF expression on rat liver in vivo and furthermore whether it protects the liver from liver fibrosis.

Methods

Some rats received carbon tetrachloride (CCl4) by subcutaneous injections every three days for six consecutive weeks, and meantime they also obtained either siRNA (0.1 mg/kg) targeting CTGF, saline or a control siRNA by intraportal vein injection to rats' liver at the same pattern. Other rats received CCl4 by subcutaneous injection for 2 weeks, followed by CCl4 and CTGF siRNA intraportal vein injection for four more weeks.

Results

Intraportal vein injection of CTGF siRNA specifically reduced the expression of CTGF protein in rat liver, and these effects were maintained for 3 days. Six weeks after CCl4 injection, prominent upregulations were observed in the gene expressions of CTGF, type I, III collagen, laminin, tissue inhibitor metal proteinase‐1 (TIMP‐1) and transforming growth factor‐β1 (TGF‐β1) in saline or control siRNA‐treated rats livers. Administrating CTGF siRNA for 4 or 6 weeks, by contrast, markedly attenuated the induction of CTGF, type I, III collagen, laminin, TIMP‐1 and TGF‐β1 genes, whereas Smad2, 7 gene expression was not affected. The number of active hepatic stellate cells (HSCs) determined by the expression of α‐smooth muscle actin was also significantly decreased. The CTGF siRNA treatment markedly reduced serum procollagen type III, hepatic hydroxyproline and liver fibrosis staging.

Conclusions

Silencing CTGF expression with siRNA demonstrates therapeutic potential to prevent liver fibrosis by inhibiting HSC activation with consequent extracellular matrix accumulation and the upregulation of TGF‐β1 gene expression. Copyright © 2006 John Wiley & Sons, Ltd.
Applications of functional magnetic resonance imaging in psychiatry
Authors: Mitterschiffthaler Martina T. , Ettinger Ulrich , Mehta Mitul A. , Mataix‐Cols David , Williams Steve C.R.
Published: May 2006

While the use of MRI techniques has become a cornerstone of the neurology clinic, the application of such methods in psychiatry was rather limited until the advent of functional magnetic resonance imaging (fMRI). Over the past decade fMRI has superseded radionuclide‐imaging techniques and blossomed into a widely used psychiatric research tool. This review focuses on the neurobiological findings from fMRI research in three less well‐documented psychiatric disorders: attention deficit hyperactivity disorder (ADHD), depression, and obsessive‐compulsive disorder (OCD). Although there was some disparity in early findings, greater standardization of image acquisition, analysis, and paradigms, and improved clinical classification are leading to a greater convergence of observations from different laboratories. fMRI is also beginning to realize its potential as an important mediator between genes and phenotypes, and may thus contribute to a better understanding of the pathophysiology of major neuropsychiatric diseases. The role of fMRI in the objective assessment of therapeutic intervention and early prediction of response to treatment is also discussed. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
A synoptic climatology of tropospheric ozone episodes in Sydney, Australia
Authors: Hart Melissa , De Dear Richard , Hyde Robert
Published: May 2006

Concentrations of tropospheric ozone often exceed Australian air quality goals in Sydney during summer. However, features in the occurrence of ozone in Sydney are yet to be fully explained. Meteorological conditions associated with ozone episodes in Sydney are caused by complex interactions between synoptic and meso‐scale processes. This paper discusses the meteorological influences behind ozone pollution episodes in Sydney.

A synoptic climatology of ozone episodes in Sydney was generated using multivariate statistical techniques, including principal component analysis (PCA) and a two‐stage cluster analysis, to classify days into meteorologically homogeneous synoptic categories. Surface and upper air meteorological data for warm months (Oct–Mar) over a 10‐year period were used as input into the statistical analyses. Eleven synoptic categories were identified in Sydney during the warm season and ozone concentrations associated with each of the synoptic categories were investigated. One synoptic category was found to be associated almost exclusively with high pollution concentrations. High ozone concentrations were found to be associated with a high‐pressure system located in the middle to eastern Tasman Sea producing light northwesterly gradient winds, an afternoon sea breeze, high afternoon temperatures, a shallow mixing height at the coast and warming aloft during the day.

Over 90% of all days exceeding current air quality goals for ozone in Sydney fell within the synoptic category associated with the highest ozone concentrations. It is envisaged that results from this research will be useful to Australian regulatory bodies from both a forecast point of view and for the siting of future ozone precursor sources in Sydney and surrounding regions. Copyright © 2006 Royal Meteorological Society
Bitterness of saponins and their content in dry peas
Authors: Heng Lynn , Vincken Jean‐Paul , van Koningsveld Gerrit , Legger Aagje , Gruppen Harry , van Boekel Tiny , Roozen Jacques , Voragen Fons
Published: May 2006

The bitterness of a saponin mixture (containing saponin B and DDMP (2,3‐dihydro‐2,5‐dihydroxy‐6‐methyl‐4H‐pyran‐4‐one) saponin in a ratio of 1:4) and saponin B obtained from dry peas were established by a trained panel using line scaling. Both saponins were found to be bitter. However, the saponin mixture, and hence DDMP saponin, was found to be significantly more bitter than saponin B. The bitterness perceived correlated with the saponin concentration. In addition to saponin bitterness, the saponin content and composition of 16 dry pea varieties were also investigated. In two varieties, DDMP saponin was the only saponin present whereas, in the rest of the varieties, DDMP saponin was more abundant than saponin B. The pea varieties investigated differed significantly in saponin content. The amounts of DDMP saponin ranged from 0.7 to 1.5 g kg−1 (dry matter), whereas those of saponin B ranged from 0 to 0.4 g kg−1. As saponins are bitter, pea varieties with lower saponin contents would be preferred for use in food production. Copyright © 2006 Society of Chemical Industry
Possibilities and limitations of fast GC with narrow‐bore columns
Authors: Dömötörová Milena , Kirchner Michal , Matisová Eva , de Zeeuw Jaap
Published: May 2006

In this work, two narrow‐bore capillary columns with different internal diameters (I.D.) 0.15 mm (15 m length, 0.15 μm film thickness) and 0.10 mm (10 m length, 0.10 μm film thickness) with the same stationary phase (5% diphenyl 95% dimethylsiloxane), phase ratio and separation power were compared with regard to their advantages, practical limitations and applicability in fast GC on commercially available instrumentation. The column comparison concerns fast GC method development, speed and separation efficiency, the sample transfer into the column utilizing split and splitless inlet, sample capacity, detection (analysing compounds of a wide range of polarities and volatilities – even n‐alkanes C16–C28 and selected pesticides) and ruggedness (in the field of ultratrace analysis of pesticide residues in real matrix). Under conditions corresponding to speed/separation efficiency trade‐off 0.10 mm I.D. versus 0.15 mm I.D. column provides a speed gain of 1.74, but all other parameters investigated were better for the 0.15 mm I.D. column concerning more efficient sample transfer from inlet to the column using splitless injection, no discrimination with split injection. Better sample capacity (three times higher for the 0.15 mm than for the 0.10 mm I.D. column) resulted in improved ruggedness and simpler fast GC‐MS method development.
Changes in soil properties of an eastern Australian vertisol irrigated with treated sewage effluent following gypsum application
Authors: Hulugalle N. R. , Weaver T. B. , Ghadiri H. , Hicks A.
Published: May 2006

Historically many towns in inland Australia disposed of their treated sewage by pumping into local rivers. This is no longer a feasible proposition. Alternatives to river pumping include irrigation and/or aquaculture. As treated sewage effluent may contain large amounts of nitrogen, phosphorus and sodium salts, if not managed carefully, soil salinity, sodicity and nutrient accumulation could increase. The objective of this study was to evaluate if gypsum application had any effect on soil‐quality changes in a Vertisol due to irrigating a cotton–wheat rotation with tertiary treated sewage effluent. The treatments were application of 2·5 t ha−1of gypsum in June 2000 before commencing irrigation and an untreated control. Annually, between June 2000 and April 2004, irrigation water quality and soil changes in nitrate‐N, EC1:5, pH, organic carbon, Cl, dispersion index, and exchangeable cations to a depth of 1·8 m were measured and deep drainage inferred with the chloride mass balance method. Cotton lint yield and fibre characteristics were also evaluated.

Irrigation with treated sewage effluent increased exchangeable Na in all depths, and exchangeable Ca and K in the clayey‐textured surface 0·6 m, but decreased exchangeable Ca and K, and SOC in the coarser clay‐loam‐textured depths > 0·6 m. Nitrate‐N leaching, associated with deep drainage had occurred, as the crops had not used all the N in irrigation water. Gypsum application decreased exchangeable Ca, increased dispersion and during the 2003–2004 season deep drainage, but had no effect on salinity, sodicity or pH. Application of commercial gypsum at sub‐optimal rates with sodium‐rich irrigation water is, therefore, unlikely to improve soil properties. Stubble incorporation before sowing cotton in 2003 appears to have mobilized gypsum applied during 2000. Gypsum application reduced cotton lint yield and fibre quality during 2003–2004. Copyright © 2006 John Wiley & Sons, Ltd.
The natural environment of Cupressus sempervirens in Greece as a basis for its use in the Mediterranean region
Authors: Brofas G. , Karetsos G. , Dimopoulos P. , Tsagari C.
Published: May 2006

This paper studies the natural stands of Cupressus sempervirens L. in Greece. C. sempervirens stands are located on the islands of Crete, Samos, Rhodes, Kos, Symi, and Milos, while populations on the islands of Chios and Kalymnos were discovered recently. Stands in the Peloponnese and in the Ionian Islands are considered introduced and naturalized. Data on natural populations show that C. sempervirens is indifferent to physiographic factors, substrate material, and physicochemical soil properties. The species grows on sites ranging from the semiarid bioclimatic zone with warm winters, to the wet zone with cold and fairly harsh winters. According to the xerothermic index in the taxon's natural distribution area, all Mediterranean bioclimate characters may appear, from intense thermo‐Mediterranean to weak meso‐Mediterranean. Cypress participates in all the vegetation zones from the thermo‐Mediterranean to mountainous Mediterranean and a cluster analysis (TWINSPAN) of sixty‐two cypress relevés led to the recognition of six woodland types defined by species composition, and assigned to three alliances: Oleo‐Ceratonion, Quercion ilicis, and Acero‐Cupression. This great plasticity of the species with regard to natural environmental factors, together with its relative resistance to fire, renders cypress one of the most valuable forest species for a large part of the Mediterranean region. Copyright © 2006 John Wiley & Sons, Ltd.
Sodicity‐induced land degradation and its sustainable management: problems and prospects
Authors: Qadir M. , Noble A. D. , Schubert S. , Thomas R. J. , Arslan A.
Published: May 2006

Currently at least 20 per cent of the world's irrigated land is salt‐affected. However, projections of global population growth, and of an increased demand for food and fibre, suggest that larger areas of salt‐affected soil will need to be cropped in the future. About 60 per cent of salt‐affected soils are sodic, and much of this land is farmed by smallholders. Ameliorating such soils requires the application of a source of calcium (Ca2+), which replaces excess sodium (Na+) at the cation exchange sites. The displaced Na+ is then leached from the root zone through excess irrigation, a process that requires adequate flows of water through the soil. However, it must now be recognized that we can no longer conduct sodic soil amelioration and management solely with the aim of achieving high levels of crop productivity. The economic, social, and environmental impacts of different soil‐amelioration options must also be considered. A holistic approach is therefore needed. This should consider the cost and availability of the inputs needed for amelioration, the soil depth, the level to which sodicity needs to be reduced to allow cropping, the volume and quality of drainage water generated during amelioration, and the options available for drainage‐water disposal or reuse. The quality and cost of water available for post‐amelioration crops, and the economic value of the crops grown during and after amelioration should also be taken into account, as should farmers' livelihoods, the environmental implications of amelioration (such as carbon sequestration), and the long‐term sustainable use of the ameliorated site (in terms of productivity and market value). Consideration of these factors, with the participation of key stakeholders, could sustainably improve sodic soil productivity and help to transform such soils into a useful economic resource. Such an approach would also aid environmental conservation, by minimizing the chances of secondary sodicity developing in soils, particularly under irrigated agriculture. Copyright © 2006 John Wiley & Sons, Ltd.
Er:YAG laser cavity preparation and composite resin bonding with a single‐component adhesive system: Relationship between shear bond strength and microleakage
Authors: Bertrand Marie‐France , Semez Gianfranco , Leforestier Eric , Muller‐Bolla Michèle , Nammour Samir , Rocca Jean‐Paul
Published: May 2006

Background and Objectives

The purpose of this study was to assess the performances of a single‐component adhesive system when an Er:YAG laser was used to prepare cavities.

Study Design/Materials and Methods

Shear bond strength tests were performed on composite rods bonded with a single‐component adhesive system to dentin surfaces prepared using either bur+acid, Er:YAG laser (fluence = 44 J/cm2), or Er:YAG laser+acid. Class V cavities were prepared differently according to the molar surface: buccal surfaces were prepared using a diamond bur, and lingual surfaces using the Er:YAG laser. In group 1, cavity walls were not acid treated after Er:YAG laser preparation. In group 2, only the enamel walls were acid treated. In group 3, all the enamel and dentin walls were acid treated. Microleakage was assessed using a methylene blue dye penetration method.

Results

Bond strength values did not differ significantly between the three groups (P = 0.162). Better marginal adaptation was obtained between the composite resin and cavity walls when Er:YAG laser preparation was followed by a total acid etching (P = 0.008).

Conclusions

Our results supported the use of single‐component adhesive systems in cavities prepared using Er:YAG laser. The step of acid etching must be maintained for the whole cavity walls in regard of the microleakage values. Lasers Surg. Med. 38:615–623, 2006. © 2006 Wiley‐Liss, Inc.
Aqueous Gels of Triblock Copolymers of Ethylene Oxide and 1,2‐Butylene Oxide (Type BEB) Studied by Rheometry
Authors: Kelarakis Antonis , Havredaki Vasiliki , Yuan Xue‐Feng , Chaibundit Chiraphon , Booth Colin
Published: May 2006

Summary: A triblock copolymer of ethylene oxide and 1,2‐butylene oxide with hydrophilic central block and hydrophobic end blocks, denoted B10E227B10, was prepared and characterised. The frequency dependence of dynamic modulus was determined for micellar solutions in the concentration range of 8–20 wt.‐% and the temperature range of 5–70 °C, and the fluid/gel diagram was established. The results were combined with those reported previously for copolymers B12E227B12 and B12E114B12 to obtain insight into the effect of B‐block and E‐block length on the rheological properties of systems of this type. The results are discussed in terms of micelles forming bridged networks and, at higher concentrations, packing in structured gels.

Temperature dependence of the logarithm of storage modulus for aqueous solutions of copolymer B10E227B10 at the concentrations (wt.‐%) indicated. Conditions: f = 1 Hz, A ≈ 0.5%.

magnified image

Temperature dependence of the logarithm of storage modulus for aqueous solutions of copolymer B10E227B10 at the concentrations (wt.‐%) indicated. Conditions: f = 1 Hz, A ≈ 0.5%.
Preparation of Porous Calcium Alginate Membranes/Microspheres via an Emulsion Templating Method
Authors: Zhang Feng Ju , Cheng Guo Xiang , Gao Zhi , Li Cui Ping
Published: May 2006

Summary: A method is presented that can produce ordered macroporous alginate membranes and microspheres with a relatively narrow pore size distribution as compared to other existing porous alginate matrix generating procedures. The calcium alginate membranes and microspheres obtained were multiporous, and the pore size could readily be adjusted in the range of 1 to 10 µm by selecting appropriate initial emulsion parameters. A preliminary set of experiments was used to determine a range of conditions suitable for the formation of stable O/W emulsions consinsting of the alginate solution, liquid paraffin and surfactants. The obtained emulsions were characterized by size distribution measurements and optical microscopy. The emulsions were used to form alginate membranes and microspheres with diameters of 150–500 µm. Subsequent work was performed to remove liquid paraffin droplets, the dispersed phase of the emulsion which acted as template in the pore‐generating process, from the final alginate membranes and microspheres. The states of templates in hydrogels and the effect of template removal on the calcium alginate structures were thoroughly investigated.

Porous alginate membranes prepared via emulsion templating method.

image

Porous alginate membranes prepared via emulsion templating method.
Antitumor activity of an Ets protein, PEA3, in breast cancer cell lines MDA‐MB‐361DYT2 and BT474M1
Authors: Yu Zhenming , Xia Weiya , Wang Hong‐Ying , Wang Shao‐Chun , Pan Yong , Kwong Ka Yin , Hortobagyi Gabriel N. , Hung Mien‐Chie
Published: May 2006

Polyomavirus enhancer activator 3 (PEA3) is a member of the Ets family of transcription factors. We demonstrated in a previous study that, by downregulating the HER‐2/neu oncogene at the transcriptional level, PEA3 can inhibit the growth and development into tumors of HER‐2/neu‐overexpressing ovarian cancer cells. Here, we establish stable clones of the human breast cancer cell line MDA‐MB‐361DYT2 that express PEA3 under the control of a tetracycline‐inducible promoter. Ectopic expression of PEA3 in this cell line inhibited cell growth and resulted in cell cycle accumulation in the G1 phase. We demonstrate that expression of PEA3 in an orthotopic breast cancer model inhibited tumor growth and prolonged the survival of tumor‐bearing mice. In a parallel experiment with another breast cancer cell line, BT474M1, we were unable to obtain stable PEA3‐inducible transfectants, suggesting that PEA3 may exert a strong growth inhibition effect in this cell line. Indeed, PEA3 coupled with the liposome SN2 demonstrated therapeutic effects in mice bearing tumors induced by BT474M1. These results provide evidence for the antitumor activity of PEA3 in human breast cancers. © 2006 Wiley‐Liss, Inc.
On non‐Newtonian incompressible fluids with phase transitions
Authors: Kim Namkwon , Consiglieri Luisa , Rodrigues José Francisco
Published: May 2006

A modified model for a binary fluid is analysed mathematically. The governing equations of the motion consists of a Cahn–Hilliard equation coupled with a system describing a class of non‐Newtonian incompressible fluid withp‐structure. The existence of weak solutions for the evolution problems is shown for the space dimensiond=2 withp⩾ 2 and ford=3 withp⩾ 11/5. The existence of measure‐valued solutions is obtained ford=3 in the case 2⩽p< 11/5. Similar existence results are obtained for the case of nondifferentiable free energy, corresponding to the density constraint |ψ| ⩽ 1. We also give regularity and uniqueness results for the solutions and characterize stable stationary solutions. Copyright © 2006 John Wiley & Sons, Ltd.
Structure elucidation of a novel group of dithiocarbamate derivatives using 1D and 2D NMR spectroscopy
Authors: Li Qin , Yang Chunhui , Ge Ze‐Mei , Li Runtao , Cui Yuxin
Published: May 2006

Compounds 1–7 form a novel group of dithiocarbamates, first synthesized from the reaction of a series of primary amines with carbon disulfide and 3‐bromo ethyl pyruvate in the presence of anhydrous potassium phosphate. Structure elucidation of this group of compounds was accomplished using extensive 1D and 2D NMR spectroscopic studies, including 1H, 13C, COSY, NOESY, HSQC, and gHMBC experiments. The distinction between the linear structures I, II and the cyclic structure III was made mainly on the basis of the analysis of the cross peak between H‐2 and H‐4a in the COSY spectra, in combination with the long‐range correlation between H‐2 and C‐4, 6 in the gHMBC spectra. Copyright © 2006 John Wiley & Sons, Ltd.
Ultrasound measurement of detrusor wall thickness in healthy adults
Authors: Oelke Matthias , Höfner Klaus , Jonas Udo , Ubbink Dirk , de la Rosette Jean , Wijkstra Hessel
Published: May 2006

Aims

Measurements of detrusor wall thickness (DWT) are used to diagnose bladder outlet obstruction (BOO). No values of DWT exist in healthy adults so far. These values, however, are necessary to judge DWT in patients with suspected BOO correctly. The aim of this study was to determine DWT in healthy adults and to investigate if bladder filling, gender, age, or body‐mass index (BMI) influences DWT.

Materials and Methods

In 55 healthy adult volunteers between 15 and 40 years of age, DWT was measured at the anterior bladder wall with a 7.5 MHz ultrasound probe and with a full bladder. In nine of those volunteers, an urodynamic investigation was performed additionally during which DWT was measured in steps of 50 ml until 300 ml and in steps of 100 ml until the maximum bladder volume.

Results

DWT decreases rapidly during the first 250 ml of bladder filling but, thereafter, remains almost stable until maximal bladder capacity. No statistical difference was found between DWT at 250 ml and DWT at a higher bladder filling. Men had a greater DWT compared to women (1.4 vs. 1.2 mm, P < 0.001). The age and BMI did not have a significant impact on DWT.

Conclusions

DWT remains stable at a bladder filling of 250 ml. At this state of bladder filling, DWT between different groups are comparable. Men have to be evaluated separately from women. Neurourol. Urodynam. © 2006 Wiley‐Liss, Inc.
Cardiovascular risk of selective cyclooxygenase‐2 inhibitors and other non‐aspirin non‐steroidal anti‐inflammatory medications
Authors: Velentgas Priscilla , West William , Cannuscio Carolyn C. , Watson Douglas J. , Walker Alexander M.
Published: May 2006

Pharmacoepidemiology and Drug Safety 10.1002/pds. 1192(in press)
Resistive loading of photovoltaic modules and arrays for long‐term exposure testing
Authors: Osterwald C. R. , Adelstein J. , Cueto J. A. del , Sekulic W. , Trudell D. , McNutt P. , Hansen R. , Rummel S. , Anderberg A. , Moriarty T.
Published: May 2006

This paper investigates the feasibility of using fixed resistors instead of active maximum power tracking as electrical loads for long‐term exposure testing of photovoltaic modules and arrays. The method of investigation was to compare resistive versus active loading on two modules for which historic current‐voltage data over time were available. Also, a small amorphous silicon array was installed with a resistive load and the performance has been monitored versus time. The major conclusion of this work is that fixed resistive loading is an inexpensive and viable means of loading photovoltaic devices for exposure testing if the resistance value used is close to the ratio of the voltage to the current at the maximum power point under Standard Test Conditions. Copyright © 2006 John Wiley & Sons, Ltd.
Profiling the array of Cav3.1 variants from the human T‐type calcium channel geneCACNA1G: Alternative structures, developmental expression, and biophysical variations
Authors: Emerick Mark C. , Stein Rebecca , Kunze Robin , McNulty Megan M. , Regan Melissa R. , Hanck Dorothy A. , Agnew William S.
Published: May 2006

We describe the regulated transcriptome ofCACNA1G, a human gene for T‐type Cav3.1 calcium channels that is subject to extensive alternative RNA splicing. Fifteen sites of transcript variation include 2 alternative 5′‐UTR promoter sites, 2 alternative 3′‐UTR polyadenylation sites, and 11 sites of alternative splicing within the open reading frame. A survey of 1580 fetal and adult human brain full‐length complementary DNAs reveals a family of 30 distinct transcripts, including multiple functional forms that vary in expression with development. Statistical analyses of fetal and adult transcript populations reveal patterns of linkages among intramolecular splice site configurations that change dramatically with development. A shift from nearly independent, biased splicing in fetal transcripts to strongly concerted splicing in adult transcripts suggests progressive activation of multiple “programs” of splicing regulation that reorganize molecular structures in differentiating cells. Patch‐clamp studies of nine selected variants help relate splicing regulation to permutations of the gating parameters most likely to modify T‐channel physiology in expressing neurons. Gating behavior reflects combinatorial interactions between variable domains so that molecular phenotype depends onensemblesof coselected domains, consistent with the observed emergence of concerted splicing during development. We conclude that the structural gene and networks of splicing regulatory factors define an integrated system for the phenotypic variation of Cav3.1 biophysics during nervous system development. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Ecotoxicity testing of chemicals with particular reference to pesticides
Authors: Walker Colin H
Published: May 2006

Ecotoxicity tests are performed on vertebrates and invertebrates for the environmental risk assessment of pesticides and other chemicals and for a variety of ecotoxicological studies in the laboratory and in the field. Existing practices and strategies in ecotoxicity testing are reviewed, including an account of current requirements of the European Commission for the testing of pesticides and the recent REACH (Registration, Evaluation, Authorisation and Restrictions of Chemicals) proposals for industrial chemicals. Criticisms of existing practices have been made on both scientific and ethical grounds, and these are considered before dealing with the question of possible alternative methods and strategies both for environmental risk assessment and for ecotoxicological studies more generally. New approaches from an ecological point of view are compared with recent developments in laboratory‐based methods such as toxicity tests, biomarker assays and bioassays. With regard to the development of new strategies for risk assessment, it is suggested that full consideration should be given to the findings of earlier long‐term studies of pollution, which identified mechanisms of action by which environmental chemicals can cause natural populations to decline. Neurotoxicity and endocrine disruption are two cases in point, and biomarker assays for them could have an important role in testing new chemicals suspected of having these properties. In a concluding discussion, possible ways of improving testing protocols are discussed, having regard for current issues in the field of environmental risk assessment as exemplified by the debate over the REACH proposals. The importance of flexibility and the roles of ecologists and ecotoxicologists are stressed in the context of environmental risk assessment. Copyright © 2006 Society of Chemical Industry
First principles calculations of the ground state properties and structural phase transformation in ZrN
Authors: Salguero L. A. , Mancera L. , Rodríguez J. A. , Takeuchi N.
Published: May 2006

We have studied the structural an electronic properties of ZrN using the Full Potential Linearized Augmented Plane Waves (FPLAPW) method. Four different crystal structures were considered in our study: cubic NaCl, cubic CsCl, wurtzite and zincblende. Rocksalt is the calculated ground state structure, but our calculations predict a phase transformation from NaCl to a CsCl structure at high pressure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Metal–insulator transition induced by electronic and structural modulations in oxygen‐deficient perovskite‐type TbBaCo2O5.5
Authors: Hidaka M. , Soejima M. , Wijesundera R. P. , Soda M. , Sato M. , Choi Sun‐Hee , Sung Nark Eon , Kim Min Gyu , Lee Jay Min
Published: May 2006

The metal–insulator (M–I) transition at about 340 K (T MI) in TbBaCo2O5.5 has been investigated by X‐ray absorption spectra near Tb‐LIII, Ba‐LII, and Co‐K edges. In the metallic and insulating phases, the high‐density unoccupied bands of Tb‐6dσ and Ba‐6dσ occupy just above a Fermi level (E F), while the positive charge‐transfer Tb‐5dn Lm and Ba‐5dn Lm bands are just below E F. The narrow positive charge‐transfer Co‐3d7(e g)L band is just below E F, where L represents a hole induced in the valence band of O‐2p. It is considered that the metallic conductivity above T MI results from the (p–d) hybridized holes in the top region of the O‐2p valence band and the hopping electrons in the bottom of the O‐2p conduction band. The spin‐state transition for Co ions in the CoO6 octahedra and the CoO5 pyramids does not occur at T MI. The local structural distortion induced around the Ba ions, but not around the Tb and Co ions, mainly affects the electronic configuration interaction between the Ba‐5d and the O‐2p orbitals in BaO. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Substantial pressure effect on the resistivity and Curie temperature for the diluted magnetic semiconductor Sb2–xVxTe3
Authors: Dyck J. S. , Ahilan K. , Aronson M. C. , Uher C. , Lošťák P.
Published: May 2006

The influence of hydrostatic pressure on the electrical resistivity ρ and ferromagnetic transition temperature T C of bulk, single crystal Sb1–x Vx Te3 with x = 0.03 is presented. Pressure strongly suppresses ρ at all temperatures, with an overall decrease of about 35% at 1.6 GPa. The peak in ρ , a signature of T C, moves to lower temperature with increasing pressure. An overall suppression of T C near 40% at 1.6 GPa is observed. The results are discussed within the context of a carrier‐mediated ferromagnetic exchange interaction. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plain DFT and hybrid HF‐DFT LCAO calculations of SnO2 (110) and (100) bare and hydroxylated surfaces
Authors: Evarestov R. A. , Bandura A. V. , Proskurov E. V.
Published: May 2006

The density functional LCAO calculations using DFT (PBE) and hybrid HF‐DFT (B3LYP) functionals are presented for the electronic and structural properties of bare and hydroxylated low index surfaces of SnO2 crystal. The dissociative and associative water adsorption on (110) and (100) SnO2 surfaces is investigated. The role of geometrical and chemical‐bonding factors in the relative stability of different adsorption structures is discussed. The comparison of plain DFT functionals with the B3LYP hybrid functional shows that, in contrast to former DFT plane‐wave calculations (spontaneous dissociation), an associative adsorption of the water molecules becomes possible not only in the case of the (100) surface but also at the most stable (110) surface. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and optical properties of CuAlTe2
Authors: Korzun B. V. , Fadzeyeva A. A. , Mudryi A. V. , Schorr S.
Published: May 2006

Bulk crystals of the ternary CuAlTe2 semiconductor with chalcopyrite structure were prepared and their structural and optical properties, including transmission and reflectance, were investigated. It was evaluated that the value of optical gap energy equals 1.65 eV at 293 K. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Updating interleukin‐6 classic‐ and trans‐signaling
Authors: Scheller Jürgen , Grötzinger Joachim , Rose‐John Stefan
Published: May 2006

The cytokine interleukin‐6 has been identified and cloned among others as B‐cell stimulatory factor, hepatocyte stimulating factor, plasmacytoma growth factor, and interferon beta‐2. Consequently, it emerged, that IL‐6 controls a huge variety of cellular functions, among them induction of the acute phase response in the liver, mediation of inflammation and malignant transformation. In this review, we summarize the so called classical IL‐6 signaling, which is mediated by the complex of IL‐6, the membrane bound IL‐6R and two gp130 molecules, and an alternative pathway called trans‐signaling, which apparently contributes to the development of chronic inflammation and cancer. During trans‐signaling an agonistic soluble IL‐6R is generated, which sensitizes cells lacking the membrane bound IL‐6R. Finally, we discuss specific inhibition of IL‐6‐trans‐signaling processes by a naturally occurring soluble form of gp130, demonstrating that this protein may emerge as an important future therapeutic in clinical applications for chronic inflammation.
Effect of Processing of Sword Beans (Canavalia gladiata) on Physicochemical Properties of Starch
Authors: Ekanayake Sagarika , Nair Baboo M. , Asp Nils‐Georg , Jansz Errol R.
Published: May 2006

The effect of various processing methods on physico‐chemical properties of sword bean starch was studied. Seed grits and flour were cooked with and without soaking, wet‐autoclaved, and roasted. The changes in starch associated with these processing methods were studied by observing changes in granular structure, water solubility index, water absorption index, molecular size distribution and the degree of gelatinization estimated by differential scanning calorimetry. Intact, ungelatinized starch granules of raw and dry‐heat treated samples were observed under the light microscope. The starch granules were elliptical in shape and had an average length and breadth of 37–40 μm and 27 μm, respectively. Wet‐processed samples had the lowest water solubility, higher water absorption and lower gelatinization enthalpies than the raw bean flour, whereas the dry heat‐treated samples showed higher water solubility and higher gelatinization enthalpies. The starch molecular size distribution pattern showed a higher amount of high molecular size carbohydrates in dry heat‐treated samples and a large fraction of intermediate molecular size carbohydrates in the wet‐processed samples. The low molecular size carbohydrate content was low in wet‐processed samples where processing was done with excess water.