bluuebunny/crossref_metadata_2025 huggingface dataset:
Consequences of error
Authors: Gordon Derek , Finch Stephen J.
Published: July 2006

Although misclassification errors are among the most ubiquitous elements of any gene mapping study, their consequences are often omitted or ignored. These errors, however, can cause deleterious results for the analysis of genetic data. Here we review the consequences of misclassification error in genetic linkage and association analysis. We also present recent methodological advances to estimate error rates and to incorporate errors into statistical tests of gene mapping. Computations for many of these advances may be performed through freely available software.
Posttranslational modifications to plants – glycosylation
Authors: Tekoah Yoram
Published: July 2006

Posttranslational modifications (PTMs) of plants include glycosylation. As in mammals, plants attach both N‐ and O‐linked glycans, but the systems are not identical. More is known about the N‐linked type glycans. The complex N‐linked glycans of plants differ markedly in structure from those of animals. They more closely resemble those of insects and molluscs by not containing terminal sialic acids. The complex type glycans may contain an α‐(1,3)‐fucose (Fuc) linked to the proximal GlcNAc residue and/or a β‐(1,2)‐xylose (Xyl) residues attached to the α‐linked mannose (Man) of the glycan core, similar to what is found in insects and molluscs. These additional epitopes are thought to have antigenic and/or allergenic properties. Less is known about O‐linked glycans in plants. Recently, plants and algae have been utilized for the production of therapeutic proteins. Much more information on glycosylation of plants and algae and the ability to manipulate the glycosylation will have to be acquired, if these therapeutic proteins are to be effective.
Protein–ligand docking and structure‐based drug design
Authors: Oledzki Peter R. , Laurie Alasdair T. R. , Jackson Richard M.
Published: July 2006

Protein‐ligand docking and de novo drug design have become increasingly important tools in aiding the drug design process, particularly with the recent increase in the number of pharmaceutically relevant macromolecular structures that have become available. Here, we review current methods and their applications, and highlight some recent successes in structure‐based drug design.
Colloidal Synthesis of Hollow Cobalt Sulfide Nanocrystals
Authors: Yin Y. , Erdonmez C. K. , Cabot A. , Hughes S. , Alivisatos A. P.
Published: July 2006

Formation of cobalt sulfide hollow nanocrystals through a mechanism similar to the Kirkendall Effect has been investigated in detail. It is found that performing the reaction at > 120 °C leads to fast formation of a single void inside each shell, whereas at room temperature multiple voids are formed within each shell, which can be attributed to strongly temperature‐dependent diffusivities for vacancies. The void formation process is dominated by outward diffusion of cobalt cations; still, the occurrence of significant inward transport of sulfur anions can be inferred as the final voids are smaller in diameter than the original cobalt nanocrystals. Comparison of volume distributions for initial and final nanostructures indicates excess apparent volume in shells, implying significant porosity and/or a defective structure. Indirect evidence for fracture of shells during growth at lower temperatures was observed in shell‐size statistics and transmission electron microscopy images of as‐grown shells. An idealized model of the diffusional process imposes two minimal requirements on material parameters for shell growth to be obtainable within a specific synthetic system.
Inside Front Cover: Quantitative Measurement of the Local Surface Potential of π‐Conjugated Nanostructures: A Kelvin Probe Force Microscopy Study (Adv. Funct. Mater. 11/2006)
Authors: Liscio A. , Palermo V. , Gentilini D. , Nolde F. , Müllen K. , Samorì P.
Published: July 2006

Kelvin probe force microscopy provides quantitative insight into the electronic properties of thin molecular layers, as shown by the results of P. Samorì and co‐workers on p. 1407. In the cartoon shown in the inside front cover, a scanning charged tip probes the local surface potential of a self‐assembled layer, inducing charge polarization into a nanoscale “effective area”. These measurements make it possible to unravel the interplay between structural and electronic properties of molecule‐based materials and devices.

We describe a systematic study on the influence of different experimental conditions on the Kelvin probe force microscopy (KPFM) quantitative determination of the local surface potential (SP) of organic semiconducting nanostructures of perylene‐bis‐dicarboximide (PDI) self‐assembled at surfaces. We focus on the effect of the amplitude, frequency, and phase of the oscillating voltage on the absolute surface potential value of a given PDI nanostructure at a surface. Moreover, we investigate the role played by the KPFM measuring mode employed and the tip–sample distance in the surface potential mapping by lift‐mode KPFM. We define the ideal general conditions to obtain a reproducible quantitative estimation of the SP and we find that by decreasing the tip–sample distance, the area of substrate contributing to the recorded SP in a given location of the surface becomes smaller. This leads to an improvement of the lateral resolution, although a more predominant effect of polarization is observed. Thus, quantitative SP measurements of these nanostructures become less reliable and the SP signal is more unstable. We have also devised a semi‐quantitative theoretical model to simulate the KPFM image by taking into account the interplay of the different work functions of tip and nanostructure as well as the nanostructure polarizability. The good agreement between the model and experimental results demonstrates that it is possible to simulate both the change in local SP at increasing tip–sample distances and the 2D potential images obtained on PDI/highly oriented pyrolytic graphite samples. These results are important as they make it possible to gain a quantitative determination of the local surface potential of π‐conjugated nanostructures; thus, they pave the way towards the optimization of the electronic properties of electroactive nanometer‐scale architectures for organic (nano)electronic applications.
Bubble dynamics during degassing of liquids at microgravity conditions
Authors: Divinis Nikolaos , Karapantsios Thodoris D. , de Bruijn Robert , Kostoglou Margaritis , Bontozoglou Vasilis , Legros Jean‐Claude
Published: July 2006

This work investigates the growth of bubbles generated in a liquid saturated with dissolved CO2 when its temperature is rapidly and locally raised above the saturation value, still below the boiling point of the test liquid. Three test liquids with different physical and transport properties were studied: water, glycerine/water mixture 42/58 w/w, and n‐heptane. Bubbles grow at the tip of a roughly spherical miniature heater (thermistor), whose temperature varies linearly with the power of an applied heat pulse. Nucleation and growth of single bubbles is studied, triggered either by continuous heat pulses or by intermittent heat pulses. A one‐dimensional spherically symmetric bubble growth model based on heat and mass transfer on the liquid side is employed to extract the average bubble temperature evolution curves from the experimental bubble growth curves. Comparisons between extracted average bubble temperature evolution data and measured thermistor temperatures reveal features of the heat‐triggered bubble growth. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Environmental technical and administrative innovations in the Canadian manufacturing industry
Authors: Henriques Irene , Sadorsky Perry
Published: July 2006

This paper explores whether the adoption of an EMS and/or TQM, both administrative innovations, lead to the development of cleaner technological innovations. We draw on the stakeholder influence literature and Daft's (1978) dual core model of organizational innovation to determine the factors affecting a facility's decision to undertake cleaner technological innovations. Using Canadian facility level manufacturing data, we find that an EMS reduces the likelihood that a facility will implement environmental technologies that change the production process (clean technologies) while TQM increases the likelihood that the facility will implement clean technologies. We also find that administrative pressures (corporate headquarters and shareholders/investors) have no impact on technological innovations while external stakeholders such as regulators, community groups and environmental groups as well as customers and suppliers each increase the likelihood that facilities will use cleaner technologies. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
Types and influential factors of consumers' non‐purchasing ecological behaviors
Authors: Tilikidou Irene , Delistavrou Antonia
Published: July 2006

This article presents an examination of non‐purchasing ecological behaviors and their influential factors. The results indicate that consumers who engage in recycling, pro‐environmental post‐purchasing behavior and pro‐environmental activities are highly educated people. Among them, those who are mostly involved in recycling and the non‐energetic, rather traditional, activities are mostly influenced by their positive attitudes towards recycling, as well as by their social responsibility. Those who adopt more energetic, more active, behaviors are mostly influenced by their beliefs that they hold power over politicians and politics. It was also found that those who are engaged in one type of non‐purchasing pro‐environmental behavior are more likely to engage in another type as well. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
Intermittent hypobaric hypoxia‐induced oxidative stress in rat erythrocytes: protective effects of vitamin E, vitamin C, and carnitine
Authors: Devi S. Asha , Vani R. , Subramanyam M. V. V. , Reddy Shiva Shankar , Jeevaratnam K.
Published: July 2006

This study was aimed at determining the effect of vitamin E, vitamin C, and carnitine on intermittent hypobaric‐hypoxia‐induced oxidative stress (OS) in erythrocytes. For this purpose, male Wistar rats of 4 months of age were orally supplemented with one of the antioxidants prior to exposure to altitudes of 5700 m or 6300 m. Hemoglobin (Hb) and OS indices such as osmotic fragility and hemolysis were measured together with lipid peroxidation (LPO) and protein oxidation. The increase in Hb was accompanied by increase in activities of antioxidant enzymes, superoxide dismutase (SOD), and catalase (CAT) during exposure to both the altitudes without any further elevation by supplements. The extent of reduction in osmotic fragility and hemolysis by vitamin E and carnitine was greater at 6300 m than at 5700 m. Increase in LPO products, for example, malondialdehyde (MDA) and lipofuscin‐like autofluorescent substances (AFS) was noticeable at both the altitudes, and vitamin E and carnitine were effective in reducing LPO. While protein oxidation products such as carbonyl content (PrC) and advanced oxidation protein products (AOPP) increased at 6300 m, protein sulphydryl (P‐SH) content decreased. P‐SH levels were restored on supplementation of antioxidants. Hence, our results indicate that vitamin E, vitamin C, and carnitine may be beneficial in overcoming OS and hemolysis under situations such as intermittent hypobaric hypoxia (IHH) and hypobarotherapy wherein hypoxia is used to correct many pathological situations in humans. Further, this study suggests that supplementation of vitamin E, vitamin C, and L‐carnitine alone and not in combination can be beneficial in attenuating the OS associated with IHH compared to the unsupplemented rats exposed to two different altitudes. Copyright © 2006 John Wiley & Sons, Ltd.
A study of serum lipid profile and serum apolipoproteins A1 and B in Indian male violent criminal offenders
Authors: Chakrabarti Nandini , Sinha V.K.
Published: July 2006

Background High cholesterol has been advanced as the most important factor in the development of coronary artery disease. Most panels have recommended population‐wide dietary restrictions, yet a body of evolving data yields evidence of the hazards of low cholesterol, including links to aggression and hostility.

Objectives The aim of this study was to compare the serum lipid profile and serum apolipoproteins A1 and B of men with a violent criminal record and men with no criminal history.

Method Fasting blood samples were collected from 30 men with a known history of violent crime and 30 men with no criminal record. Serum lipid profile and serum apolipoproteins A1 and B were measured in each sample, and compared between the two groups.

Results The group with the violent criminal record showed significantly lower total cholesterol, lower LDL cholesterol, higher apolipoprotein A1 and lower apolipoprotein B compared with the control group.

Conclusion Lower total cholesterol, lower LDL cholesterol, higher apolipoprotein A1 and lower apolipoprotein B could predispose to violence. Future research might explore the possibility that diets offered in prison could affect relevant pathways in lipid metabolism. Copyright © 2006 John Wiley & Sons, Ltd.
Female serial killing: review and case report
Authors: Frei Andreas , Völlm Birgit , Graf Marc , Dittmann Volker
Published: July 2006

Background Single homicide committed by women is rare. Serial killing is very infrequent, and the perpetrators are usually white, intelligent males with sadistic tendencies. Serial killing by women has, however, also been described.

Aim To conduct a review of published literature on female serial killers and consider its usefulness in assessing a presenting case.

Method A literature review was conducted, after searching EMBASE, MEDLINE and PsycINFO. The presenting clinical case is described in detail in the context of the literature findings.

Results The literature search revealed few relevant publications. Attempts to categorize the phenomenon of female serial killing according to patterns of and motives for the homicides have been made by some authors. The most common motive identified was material gain or similar extrinsic gratification while the ‘hedonistic’ sadistic or sexual serial killer seems to be extremely rare in women. There is no consistent theory of serial killing by women, but psychopathic personality traits and abusive childhood experiences have consistently been observed. The authors' case did not fit the description of a ‘typical’ female serial killer.

Discussion In such unusual circumstances as serial killing by a woman, detailed individual case formulation is required to make sense of the psychopathology in each case. Publication of cases in scientific journals should be encouraged to advance our understanding of this phenomenon. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of the subthreshold characteristics for the FC‐SGT flash memory cell
Authors: Yamazaki Hiroaki , Nakamura Hiroki , Sakuraba Hiroshi , Masuoka Fujio
Published: July 2006

In this paper, an analytical model for finding the S‐factor of the FC‐SGT flash memory cell is derived. It is confirmed that the results of analysis agree well with the three‐dimensional simulation results. In comparison with the conventional planar flash memory cell, the FC‐SGT flash memory cell has a sufficiently smaller S‐factor. As a result, it is easier to realize multilevel operation by the FC‐SGT flash memory than by the conventional planar flash memory. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(8): 34–41, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20250
Separation of coupling coefficient between resonators into electric and magnetic contributions
Authors: Awai Ikuo , Iwamura Shintaro , Kubo Hiroshi , Sanada Atsushi
Published: July 2006

It is shown that the coefficient of coupling between resonators can be derived by a perturbation method using the electromagnetic field distributions of uncoupled resonators. This method can be applied if identical resonators are symmetrically placed. It is found that there is a possibility of completing the calculations in a shorter time than by using the conventional even and odd mode frequencies. Further, since the electric and magnetic couplings can be derived separately, the physical meaning of the coupling becomes clearer. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(8): 27–33, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20251
An entropy estimator improving the bias error
Authors: Yokota Yasunari
Published: July 2006

The entropy estimation is adopted as one of the useful methods for analysis in various fields including signal processing and system identification. However, the generally used entropy estimator is actually not an unbiased estimator. In this paper, the bias in the entropy estimator, namely, the bias error, was approximately formulated using the Taylor expansion of the entropy function. This approximation formula was reorganized and the coefficients contained were estimated to derive an approximation formula expressed in the form of a power series in terms of the number of samples. The derived approximation formula for the bias error was subtracted from the entropy estimator and this difference was proposed as a new entropy estimator. With the proposed entropy estimator, since the bias error is offset, its influence is suppressed and compared to the conventional entropy estimator and the bias error was reduced by a statistically significant difference. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(8): 60–69, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20287
A system‐on‐a‐chip for real‐time software digital media processing
Authors: Kojima Keiji , Nishioka Kiyokazu , Kawaguchi Atsuo , Hosogi Koji , Komoda Norihisa
Published: July 2006

In this paper the authors propose a new system‐on‐a‐chip architecture for image processing that achieves both good processing performance and ease of software development. The architecture consists of three types of programmable processors running in parallel: a RISC CPU for bit string processing, a VLIW CPU for two‐dimensional pixel array processing, and a data transfer processor. The data transfer processor provides a function for transferring small regions in the two‐dimensional pixel array for which addresses change discretely to a data cache while converting them to continuous address data. As a result, the data cache hit rate with respect to the accesses to the small screen regions, which is used frequently in image processing, is greatly improved from around 75% to almost 100%. The authors implemented their architecture in an LSI and ran a performance evaluation using digital television decoder software and an optimized C compiler. The results confirmed that processing performance increased threefold with a 22% rise in the packaging die area. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(8): 51–59, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20288
Glucocorticoid amplifies IL‐2‐dependent expansion of functional FoxP3+CD4+CD25+ T regulatory cells in vivo and enhances their capacity to suppress EAE
Authors: Chen Xin , Oppenheim Joost J. , Winkler‐Pickett Robin T. , Ortaldo John R. , Howard O. M. Zack
Published: July 2006

IL‐2 is crucial for the production of CD4+CD25+ T regulatory (Treg) cells while important for the generation of effective T cell‐mediated immunity. How to exploit the capacity of IL‐2 to expand Treg cells, while restraining activation of T effector (Teff) cells, is an important and unanswered therapeutic question. Dexamethasone (Dex), a synthetic glucocorticoid steroid, has been reported to suppress IL‐2‐mediated activation of Teff cells and increase the proportion of Treg cells. Thus, we hypothesized that glucocorticoids may be useful as costimulants to amplify IL‐2‐mediated selective expansion of Treg cells. We show in this study that short‐term simultaneous administration of Dex and IL‐2 markedly expanded functional suppressive Foxp3+CD4+CD25+ T cells in murine peripheral lymphoid tissues. In a myelin oligodendrocyte glycoprotein‐induced experimental autoimmune encephalomyelitis (EAE) mouse model, we observed that splenic CD4+CD25+ T cells failed to suppress the proliferation of CD4+CD25– T cells. Pretreatment with Dex/IL‐2 remarkably increased the proportion of CD4+FoxP3+ cells and partially restored the function of splenic CD4+CD25+ T cells, and inhibited the development of EAE. Therefore, the combination of glucocorticoid and IL‐2, two currently used therapeutics, may provide a novel approach for the treatment of autoimmune diseases, transplant rejection and graft‐vs.‐host disease.
Transgenic expression of a CD83‐immunoglobulin fusion protein impairs the development of immune‐competent CD4‐positive T cells
Authors: Lüthje Katja , Cramer Sven O. , Ehrlich Svenja , Veit Alexandra , Steeg Christiane , Fleischer Bernhard , Bonin Arne von , Breloer Minka
Published: July 2006

The murine transmembrane glycoprotein CD83 is an important regulator for both thymic T cell maturation and peripheral T cell response. CD83 deficiency leads to a block in the thymic maturation of CD4‐positive T cells, and interference with peripheral CD83/CD83 ligand interaction by addition of soluble CD83 suppresses immune responses in vivo and in vitro. Here we report the generation of a mouse transgenic for a fusion protein consisting of the extracellular domain of murine CD83 fused to the constant part of human IgG1 heavy chain. Thymic selection of CD4‐positive T cells was unchanged in CD83Ig transgenic and in CD83Ig/OT‐2 double‐transgenic mice. However, thymic and peripheral CD4‐positive T cells derived from CD83Ig/OT‐2 transgenic mice displayed a reduced cytokine response to antigenic stimulation in vitro, whereas CD83Ig/OT‐1‐derived CD8‐positive T cells showed normal cytokine secretion. The T cell defect was relevant in vivo, since a sub‐lethal infection with Trypanosoma cruzi led to an increased parasitemia and reduced survival rate of CD83Ig transgenic mice compared to wild‐type C57BL/6 mice. In contrast, in vivo application of recombinant CD83Ig did not result in an increase in parasitemia. Taken together our data suggest that thymic selection in the presence of CD83Ig leads to an intrinsic T cell defect of CD4‐positive T cells resembling the phenotype described for CD4‐positive T cells derived from CD83‐deficient mouse strains.
Third‐Order Nonlinear Optical Properties of DA‐salen‐Type Nickel(II) and Copper(II) Complexes
Authors: Tedim João , Patrício Sónia , Bessada Rosa , Morais Rui , Sousa Carla , Marques Manuel B. , Freire Cristina
Published: July 2006

Third‐order nonlinear and linear optical properties ofnickel(II) and copper(II) complexes with salen ligands, functionalised with electron donor/acceptor groups (DA‐salen), have been investigated in solution by the Z‐scan technique using an Nd:YAG laser (λinc = 1064 nm) and UV/Vis spectroscopy. The [M(DA‐salen)] complexes exhibit positive nonresonant nonlinear refractive indexes (n2I) in the range27.0–8.50·10–21 m2 W–1 and nonlinear absorption coefficients (α2I) within the range 1.80–26.0·10–17 m W–1. The latter values correspond to less than 10 % of the overall magnitude of the third‐order susceptibility, |χ3|, which is the result of the absence of electronic transitions near λinc = 1064 nm. For the group of NiII complexes, the highest n2I values are exhibited by the complexes with aromatic diimine bridges and large π‐electron delocalisation, which leads to intense electronic charge‐transfer bands (ϵ > 16000 mol–1 dm3 cm–1) in the region λ = 275–500 nm. The complexes that exhibit charge‐transfer bands near λinc/2 = 532 nm, also show the highest α2I values, a consequence of multiphoton absorption processes. For the group of CuII complexes, the highest n2I value is also observed by the complex that exhibits the most intense charge‐transfer bands in the region λ = 275–475 nm. Between NiII and CuII complexes with the same DA‐salen ligands, those of copper show always higher n2I values, indicating that NLO responses can also be fine‐tuned by the metalcentre. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
One‐Pot Synthesis of a New High‐Aluminium‐Content Super‐Microporous Aluminosilicate
Authors: Huerta Lenin , Romero‐Sarria Francisca , Marie Olivier , Guillem Carmen , Beltrán Aurelio , Latorre Julio , Beltrán Daniel , Amorós Pedro
Published: July 2006

A new super‐microporous aluminosilicate having a high aluminium content (Si/Al ca. 1) has been prepared through a surfactant‐assisted procedure with the use of a commercially available binary precursor (di‐sec‐butoxyaluminooxytriethoxysilane) as a single source of both Al and Si. The formation of super‐micropores is a result of a significant network shrinkage associated with the thermal elimination of the surfactant. This solid has been studied by X‐ray powder diffraction, electron microscopy, nuclear magnetic resonance spectroscopy and porosimetry. A preliminary analysis of the acidity and the catalytic activity of the super‐microporous solid for the selective catalytic reduction of NOx is also presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
What a Difference One Electron Makes! Generating Low‐Coordinate Ti–C and V–C Multiply Bonded Frameworks through One Electron Oxidatively Induced α‐Hydrogen Abstractions
Authors: Mindiola Daniel J. , Bailey Brad C. , Basuli Falguni
Published: July 2006

Low‐coordinate, high oxidation state titanium and vanadium complexes containing terminal metal–carbon multiply bonded functionalities have been prepared directly or indirectly through one electron oxidatively induced α‐hydrogen abstraction reactions. This synthetic approach offers a mild entry to reactive M=C and M≡C motifs, and does not depend on external stimulants such as heat, light or base to promote the α‐hydrogen‐abstraction step. In addition, this strategic protocol avoids the use of powerful electrophiles, thus generating terminal and nucleophilic M–C multiple bonds in low‐coordination environments. In some cases terminal alkylidenes containing β‐hydrogen atoms can also be introduced through this route. This microreview surveys the synthesis and chemistry surrounding isolable titanium and vanadium complexes bearing terminal alkylidene and alkylidyne ligands. Particular emphasis will be placed on the synthesis of the high oxidation state M–C multiple bond. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
New Polar Pyrazolylborate Ligands and Their Basic Zinc Complex Chemistry
Authors: Pérez Olmo Cristina , Böhmerle Karin , Steinfeld Gunther , Vahrenkamp Heinrich
Published: July 2006

By refinement of Trofimenko’s procedures, four new tris(pyrazolyl)borate (Tp) ligands bearing pyridyl and carboxamide substituents at the 3‐positions of the pyrazole rings, were obtained. Two of them were identified by structure determinations of their potassium salts. Their coordinative properties were explored by preparing Tp*Zn‐X complexes, with X = Cl, Br, I, NO3, OAc, phenolate, thiophenolate and diorganophosphate, including the cationic complexes [Tp*Zn·L]+ with L = methanol and pyrazole. From the spectra and structure determinations of these complexes it has become evident that the polar Tp* ligands favor coordination numbers higher than four for zinc, either by inducing bidentate coordination of the coligands X and L, using the carboxamide oxygen atoms for coordination, or by linking two Tp*Zn‐X units through the pyridyl nitrogen atoms. As a result, the structural chemistry of these complexes is quite varied, and includes coordination dimers and polymers.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Ring Expansions of 2‐Alkenylazetidinium Salts – a New Route to Pyrrolidines and Azepanes
Authors: Couty François , Durrat François , Evano Gwilherm , Marrot Jérome
Published: July 2006

Series of enantiomerically pure 3‐alkenylpyrrolidines, substituted azepanes and stereodefined aminoalkenes were synthesized from 2‐alkenylazetidinium trifluoromethanesulfonate salts. The high chemoselectivity of these reactions was found to be strongly dependent both on the nature of the base involved in the process (PhLi or KHMDS) and on the relative cis or trans stereochemistry of the intermediate ammonium ylide. When the ylide and the adjacent alkene are trans, a [1,2] sigmatropic shift occurs exclusively, producing a pyrrolidine with high levels of regioselectivity. On the other hand, clean conversion into 4,5‐dehydroazepanes through a [2,3] sigmatropic shift is observed when these two groups are in a cis relationship.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Schwann cell‐like differentiation by adult oligodendrocyte precursor cells following engraftment into the demyelinated spinal cord is BMP‐dependent
Authors: Talbott Jason F. , Cao Qilin , Enzmann Gaby U. , Benton Richard L. , Achim Virginie , Cheng Xiao X. , Mills Michael D. , Rao Mahendra S. , Whittemore Scott R.
Published: July 2006

The development of remyelinating strategies designed to enhance recruitment and differentiation of endogenous precursor cells available to a site of demyelination in the adult spinal cord will require a fundamental understanding of the potential for adult spinal cord precursor cells to remyelinate as well as an insight into epigenetic cues that regulate their mobilization and differentiation. The ability of embryonic and postnatal neural precursor cell transplants to remyelinate the adult central nervous system is well documented, while no transplantation studies to date have examined the remyelinating potential of adult spinal‐cord‐derived oligodendrocyte precursor cells (adult OPCs). In the present study, we demonstrate that, when transplanted subacutely into spinal ethidium bromide/X‐irradiated (EB‐X) lesions, adult OPCs display a limited capacity for oligodendrocyte remyelination. Interestingly, the glia‐free environment of EB lesions promotes engrafted adult OPCs to differentiate primarily into cells with immunophenotypic and ultrastructural characteristics of myelinating Schwann cells (SCs). Astrocytes modulate this potential, as evidenced by the demonstration that SC‐like differentiation is blocked when adult OPCs are co‐transplanted with astrocytes. We further show that inhibition of bone morphogenetic protein (BMP) signaling through noggin overexpression by engrafted adult OPCs is sufficient to block SC‐like differentiation within EB‐X lesions. Present data suggest that the macroglial‐free environment of acute EB lesions in the ventrolateral funiculus is inhibitory to adult spinal cord‐derived OPC differentiation into remyelinating oligodendrocytes, while the presence of BMPs and absence of noggin promotes SC‐like differentiation, thereby unmasking a surprising lineage fate for these cells. © 2006 Wiley‐Liss, Inc.
Active antimetastatic immunotherapy in Lewis lung carcinoma with self EGFR extracellular domain protein in VSSP adjuvant
Authors: Ramírez Belinda Sánchez , Pestana Eduardo Suárez , Hidalgo Greta Garrido , García Tays Hernández , Rodríguez Rolando Pérez , Ullrich Axel , Férnandez Luis Enrique
Published: July 2006

The epidermal growth factor receptor (EGFR) plays a central role in regulating neoplastic processes. The EGFR overexpression in many human epithelial tumors has been correlated with disease progression and bad prognosis. Passive EGFR‐directed immunotherapy, but not active specific approaches, has already been introduced in medical oncology practice. Then we wonder if mice immunization with the extracellular domain of murine EGFR (mEGFR‐ECD) in adjuvants can circumvent tolerance to self EGFR, by inducing an immune response with consequent antitumor effect. The present study demonstrated that despite mEGFR expression in thymus, strong DTH response was induced by inoculation of mice with the mEGFR‐ECD. This self‐immunization, using both CFA and very small sized proteoliposomes from Neisseria meningitidis (VSSP), promoted highly specific IgG titers, predominantly IgG2a and IgG2b. Sera from mice immunized with mEGFR‐ECD/VSSP not only recognized EGFR+ tumor cell lines by FACS, but also inhibited their in vitro growth, even in the absence of complement. Noteworthy, vaccination of mice with mEGFR‐ECD/VSSP stimulated a potent antimetastatic effect in the EGFR+ Lewis lung carcinoma model, while reproduction‐associated side effects were absent. Curiously, mice immunized with the human EGFR‐ECD (Her1‐ECD) in VSSP though induced highly specific IgG antibodies with strong in vitro cytotoxic effect over EGFR+ human cell lines, showed low cross‐reactivity with the mEGFR‐ECD. These results further encouraged the development of the Her1‐ECD/VSSP vaccine project for patients with EGFR+ tumors. © 2006 Wiley‐Liss, Inc.
β‐Cryptoxanthin suppresses the growth of immortalized human bronchial epithelial cells and non‐small‐cell lung cancer cells and up‐regulates retinoic acid receptor β expression
Authors: Lian Fuzhi , Hu Kang‐Quan , Russell Robert M. , Wang Xiang‐Dong
Published: July 2006

Recent findings of an inverse association between β‐cryptoxanthin and lung cancer risk in several observational epidemiologic studies suggest that β‐cryptoxanthin could potentially act as a chemopreventive agent against lung cancer. However, the biological activity of β‐cryptoxanthin and molecular mechanism(s) by which β‐cryptoxanthin affects lung tumourigenesis have not been studied. In the present study, we found that β‐cryptoxanthin inhibited the growth of A549 cells, a non‐small‐cell lung cancer cell line and BEAS‐2B cells, an immortalized human bronchial epithelial cell line in a dose‐dependent manner. β‐Cryptoxanthin suppressed the protein levels of cyclin D1 and cyclin E, up‐regulated the cell cycle inhibitor p21, increased the number of lung cancer cells in theG1/G0 phase and decreased those in the S phase of the cell cycle. Consistent with inhibition of the lung cancer cell growth, β‐cryptoxanthin induced the mRNA levels of retinoic acid receptor β (RARβ) in BEAS‐2B cells, although this effect was less pronounced in A549 cells. Furthermore, β‐cryptoxanthin transactivated RAR‐mediated transcription activity of the retinoic acid response element. These findings suggest a mechanism of anti‐proliferative action of β‐cryptoxanthin and indicate that β‐cryptoxanthin may be a promising chemopreventive agent against lung cancer. © 2006 Wiley‐Liss, Inc.
Profiling the humoral immune response in colon cancer patients: Diagnostic antigens from Streptococcus bovis
Authors: Tjalsma Harold , Schöller‐Guinard Marie , Lasonder Edwin , Ruers Theo J. , Willems Hans L. , Swinkels Dorine W.
Published: July 2006

The human bowel contains a large and dynamic bacterial population that is not only essential for intestinal health, but also critical for the development of diseases such as cancer. In this respect, the Gram‐positive bacterium Streptococcus bovis has been associated with colon cancer for many years. To investigate the clinical importance of this association, an immunocapture mass spectrometry assay was developed that can generate infection‐related protein profiles. The composition of these profiles is governed by the capture of specific antigens by serum antibodies from colon cancer patients. This assay showed that S. bovis antigen profiles could distinguish 11 out of 12 colon cancer patients from 8 control subjects, whereas antigen profiles derived from the gut bacterium Escherichia coli were not diagnostic for colon cancer. Moreover, S. bovis antigen profiles were also detected in polyp patients, indicating that infection with this bacterium does occur early during carcinogenesis. Highly accurate tandem mass spectrometry was used to identify one of the diagnostic antigens as a surface‐exposed heparin‐binding protein, which might be involved in attachment of S. bovis to tumor cells. Together, these findings corroborate the hypothesis that colonic lesions provide a specific niche for S. bovis, resulting in tumor‐associated “silent” infections. These infections, however, only become apparent in colon cancer patients with a compromised immune system (bacteremia) or coincidental cardiac valve lesions (endocarditis). This makes profiling of the humoral immune response against “silent” S. bovis infections a promising diagnostic tool for the early detection of human colon cancer, which is crucial for the effective treatment of this disease. © 2006 Wiley‐Liss, Inc.
MicroCT for high‐resolution imaging of ectopic pheochromocytoma tumors in the liver of nude mice
Authors: Ohta Shoichiro , Lai Edwin W. , Morris John C. , Bakan Douglas A. , Klaunberg Brenda , Cleary Susannah , Powers James F. , Tischler Arthur S. , Abu‐Asab Mones , Schimel Daniel , Pacak Karel
Published: July 2006

Successful outcomes for patients with cancer often depend on the early detection of tumor and the prompt initiation of active therapy. Despite major advances in the treatment of many cancers, early‐stage lesions often go undetected due to the suboptimal resolution of current anatomical and functional imaging modalities. This limitation also applies to preclinical animal tumor models that are crucial for the evaluation and development of new therapeutic approaches to cancer. We report a new mouse model of metastatic pheochromocytoma, generated using tail vein injection of the mouse pheochromocytoma cell (MPC) line that reproducibly generated multiple liver tumors in the animals. Furthermore, we show that in vivo microCT imaging enhanced using a hepatobiliary‐specific contrast agent, glyceryl‐2‐oleyl‐1,3‐di‐7‐(3‐amino‐2,4,6‐triiodophenyl)‐heptanoate (DHOG), detected tumors as small as 0.35 mm as early as 4 weeks after the injection of the tumor cells. This model may be useful for in vivo studies of tumor biology and for development of new strategies to treat metastatic pheochromocytoma. © 2006 Wiley‐Liss, Inc.
The use of enzymes to improve cereal diets for animal feeding
Authors: Brufau Joaquim , Francesch Maria , Pérez‐Vendrell Anna M
Published: July 2006

Exogenous enzyme supplementation of animal feeds has been practised successfully since the late 1980s. Early research demonstrated that enzymes improve the nutritional value of several main ingredients such as barley, wheat, rye and triticale. More recent studies have associated feed enzymes with environmental and welfare benefits. By 2000, around 60 enzyme products had been authorised in the European Union (EU) as feed additives, and currently around 40 of these have attained definitive EU approval. This paper reviews EU legislation relating to feed enzymes and recent advances in the understanding of enzyme properties, future potential and modes of action when added to animal feeds. First, the legislative history of feed enzymes in the EU is summarised. Recent developments in the knowledge of substrate structure and the influence of enzyme inhibitors are then discussed. Also considered is the application of enzymes to maize/soybean diets, traditionally thought to be less sensitive to improvement with enzymes. Finally, an evaluation is made of the potential of enzymes to reduce environmental pollution and to improve animal health, welfare and performance in a possible future scenario where both coccidiostats and antibiotic growth promoters are prohibited. Copyright © 2006 Society of Chemical Industry
Switchable dual-wavelength erbium-doped fiber ring laser
using bending dependent loss to switch the operating wavelength
Authors: Chen S P , Ding L , Wang S M , Li Y G , Lu K C , Zhou S H
Published: July 2006

A short wavelength band erbium-doped fiber (EDF) ring
laser emitting simultaneously at 1488.9 and 1533.9 nm is
demonstrated. The erbium-doped gain fiber has a depressed cladding
to suppress emission at longer wavelengths. The shorter emitting
wavelength is selected by a fiber Bragg grating (FBG), while the
longer emitting wavelength is selected by the strong gain and the
reabsorbing effect. Switching between the two operating
wavelengths is realized by simply changing the bending curvature
of the EDF loop.
Temperature‐Triggered Nanosphere Formation Through Self‐Assembly of Amphiphilic Polyphosphazene
Authors: Zhang Jian Xiang , Qiu Li Yan , Wu Xiao Li , Jin Yi , Zhu Kang Jie
Published: July 2006

Summary: An amphiphilic graft polyphosphazene with a molar ratio of poly(N‐isopropylacrylamide) (PNIPAm) to ethyl glycinate (GlyEt) of 0.54:1 was synthesized. This copolymer in aqueous solution exhibited two temperature induced phase transitions at 17.2 and 33.7 °C, which correspond to the transformation of primary aggregate morphology (at Tph1) and the collapse of PNIPAm chains (at Tph2) respectively. Network micelles were assembled in water at lower temperature (far below Tph1), and then narrowly dispersed nanoparticles were formed above Tph1, while inter‐nanoparticle aggregation occurred due to the collapse of PNIPAm chains surrounding the GlyEt core when the temperature was above Tph2. Through solubilization of the hydrophobic drug ibuprofen into polymeric aggregates at lower temperature, drug loaded nanospheres were prepared successfully. In vitro release revealed that sustained drug release was achieved with this novel delivery system. These results suggest that this novel copolymer could be used as a potential drug carrier, especially for the delivery of hydrophobic biocompounds through parenteral administration.

Schematic illustration of the temperature‐triggered self‐assembly process of PNIPAm/GlyEt‐PPP in aqueous solution.

magnified image

Schematic illustration of the temperature‐triggered self‐assembly process of PNIPAm/GlyEt‐PPP in aqueous solution.
Development of a functional magnetic resonance imaging simulator for modeling realistic rigid‐body motion artifacts
Authors: Drobnjak Ivana , Gavaghan David , Süli Endre , Pitt‐Francis Joe , Jenkinson Mark
Published: July 2006

Functional magnetic resonance imaging (FMRI) is a noninvasive method of imaging brain function in vivo. However, images produced in FMRI experiments are imperfect and contain several artifacts that contaminate the data. These artifacts include rigid‐body motion effects, B0‐field inhomogeneities, chemical shift, and eddy currents. To investigate these artifacts, with the eventual aim of minimizing or removing them completely, a computational model of the FMR image acquisition process was built that can simulate all of the above‐mentioned artifacts. This paper gives an overview of the development of the FMRI simulator. The simulator uses the Bloch equations together with a geometric definition of the object (brain) and a varying T model for the BOLD activations. Furthermore, it simulates rigid‐body motion of the object by solving Bloch equations for given motion parameters that are defined for an object moving continuously in time, including during the read‐out period, which is a novel approach in the area of MRI computer simulations. With this approach it is possible, in a controlled and precise way, to simulate the full effects of various rigid‐body motion artifacts in FMRI data (e.g. spin‐history effects, B0‐motion interaction, and within‐scan motion blurring) and therefore formulate and test algorithms for their reduction. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Effects of temperature and aldehyde fixation on tissue water diffusion properties, studied in an erythrocyte ghost tissue model
Authors: Thelwall Peter E. , Shepherd Timothy M. , Stanisz Greg J. , Blackband Stephen J.
Published: July 2006

Ex vivo biological sample imaging can complement in vivo MRI studies. Since ex vivo studies are typically performed at room temperature, and samples are frequently preserved by fixation, it is important to understand how environmental and chemical changes dictated by ex vivo studies alter the physical and MR properties of a sample. Diffusion and relaxation time measurements were used to assess the effects of temperature change and aldehyde fixation on the biophysical and MR properties of a model biological tissue comprised of erythrocyte ghosts suspended in buffer or agarose gel. Sample temperature was varied between 10°C and 37°C. Diffusion MRI data were analyzed with a biophysically appropriate two‐compartment exchange model. Temperature change resulted in a complex alteration of water diffusion properties due to the compartmental nature of tissues and alteration in membrane permeability. Formaldehyde, Karnovsky's solution, and glutaraldehyde all caused statistically significant changes to the biophysical and MR properties of the samples. Fixation caused large decreases in water proton T2, which was restored to near prefixation values by washing free fixative from the samples. Water membrane permeability was also significantly altered by fixation. This study demonstrates that relating in vivo MR data to chemically fixed ex vivo data requires an understanding of the effects of sample preparation. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Government, corporate or social power? The internet as a tool in the struggle for dominance in public policy
Authors: Roper Juliet
Published: July 2006

This paper sets out to demonstrate to corporations the need to monitor closely and to respond genuinely to public opinion. It predicts a rise in the power of citizens and a government response to that power that will include regulation to protect social and environmental interests.

The paper gives an overview of the ways in which the economic sector, embodied in corporations, has risen to and maintained a position of dominance both within nation states and globally. It provides a model that illustrates the power relationship between corporations, governments and the public, noting in particular that the fundamental key to corporate dominance is the positioning of the public as consumers.

Using the framework of legitimation, the paper then demonstrates and theorises the rise of opposition to the dominant order and the corporate and government responses to such opposition. It is proposed that these responses may be insufficient to maintain corporate dominance and that a new model is likely to gain ascendance. In this new model the public make a shift from consumers to citizens in order to reassert their role in governance. Internet sites of activist groups are examined in order to determine the ways in which the sites are used as a tool to facilitate a shift towards the second model. Copyright © 2002 Henry Stewart Publications