bluuebunny/crossref_metadata_2025 huggingface dataset:
Remarkable Effect of 4‐Substituted 2,2′‐Bipyridine Ligands on the Stereochemistry of Ruthenium(II) Complexes
Authors: Grabulosa Arnald , Beley Marc , Gros Philippe C.
Published: March 2008

[RuL3](PF6)2 complexes containing 4‐alkoxycarbonyl‐substituted unsymmetrical bipyridine ligands (L) have been obtained exclusively as the fac isomers by simple reaction of L with ruthenium(III) chloride in ethylene glycol under microwave irradiation. The position of the alkoxycarbonyl group on the pyridine ring and its transesterification by ethylene glycol were found critical for stereocontrol during ruthenium coordination. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
The role of retinoids and their receptors in metabolic disorders
Authors: Meissburger Bettina , Wolfrum Christian
Published: March 2008

Retinoid derivatives are potent regulators of a wide variety of cellular functions through the modulation of nuclear receptor activity. Three distinct families of retinoid receptors have been identified so far, namely retinoic acid receptors, retinoic acid X receptors, and retinoic acid‐related orphan receptors. This review focuses on retinoid signaling and the regulation of metabolic processes by the family of retinoic acid receptors in relation to the development of metabolic disorders.
Nitrogen‐Containing Tricyclic and Tetracyclic Compounds by Stereoselective Samarium Diiodide Promoted Cyclizations of Quinolyl‐Substituted Ketones – A New Access to Azasteroids
Authors: Aulenta Francesca , Wefelscheid Ulrike K. , Brüdgam Irene , Reißig Hans‐Ulrich
Published: March 2008

In this report, we describe our experiments dealing withsamarium diiodide promoted cyclizations of quinolyl‐substituted ketones 6–12 and also the attempted reductive cyclization of carbazole‐containing ketone 13. These precursors were prepared by Heck‐type coupling reactions of the corresponding hetaryl nonaflates with adequately substituted olefins as a key step. The cyclization of compounds 7–12 led to nitrogen‐containing tri‐ and tetracyclic compounds 23–28 in moderate to good yields and generally proceeded in a highly diastereoselective fashion. The azatetracycles present steroid‐like skeletons but with unnatural cis–cis annulation of rings B, C and D. We also describe the chemical modification of the styrene‐type double bond of these products, which provided highly functionalized steroid‐type compounds such as 29, 30 and 32.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Chiral Sterically Congested Phosphane‐Amide Bifunctional Organocatalysts in Asymmetric Aza‐Morita–Baylis–Hillman Reactions of N‐Sulfonated Imines with Methyl and Ethyl Vinyl Ketones
Authors: Guan Xiao‐Yang , Jiang Ying‐Qing , Shi Min
Published: March 2008

A series of chiral sterically congested phosphane‐amide bifunctional Lewis bases L1–L3 have been successfully synthesized and their application in asymmetric aza‐Morita–Baylis–Hillman (aza‐MBH) reactions of N‐sulfonated imines with activated olefins such as methyl and ethyl vinyl ketone has been investigated under mild conditions. The corresponding aza‐MBH adducts can be obtained in good‐to‐excellent yields (up to 98 %) and moderate‐to‐good enantioselectivities (up to 91 or 93 % ee) in dichloromethane at room temperature (20 °C) with these novel chiral bifunctional phosphane Lewis bases.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Two Stage Colour Modulation of Triarylmethine Dyes Derived from a Photochromic Naphthopyran
Authors: Gabbutt Christopher D. , Heron B. Mark , Kolla Suresh B. , Mcgivern Matthew
Published: March 2008

The synthesis of the unsymmetrical triarylmethine dyes 4derived from a lithiated naphthopyran and diaryl ketones is reported. In toluene solution 4 display a typical reversible photochromic response becoming coloured upon irradiation with UV light and fading upon cessation of irradiation. At low pH an intensely coloured dye cation is generated and UV irradiation of this solution results in a further colour change as a consequence of photochromic cycling of the naphthopyran unit.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Direct Electrochemistry of Myoglobin on a Room Temperature Ionic Liquid Modified Electrode and Its Application to Nitric Oxide Biosensing
Authors: Zhang Qiang , Wei Wei , Zhao Guang‐Chao
Published: March 2008

Myoglobin (Myb) was successfully immobilized on a room temperature ionic liquid (RTIL), 1‐ethyl‐3‐methyl imidazolium tetrafluoroborate ([EMIM][BF4]) modified basal plane graphite (BPG) electrode. The electrochemical behavior of Myb on RTIL modified BPG electrode was explored and the results from cyclic voltammetry (CV) showed a well‐defined and quasi‐reversible CV peaks with a formal potential of −0.379 V (versus Ag/AgCl) in a phosphate buffer solution (pH 7.0). RTIL shows an obvious promotion for the direct electron‐transfer between Myb and BPG electrode. Myb adsorbed on electrode surface exhibits an obvious electrocatalytic activity for the reduction of nitric oxide (NO). The catalytic current is corresponding linearly to the NO concentration in the range of 7.0×10−7 to 7.0×10−6 M with a limit of detection of 2.0×10−7 M (three times the ratio of signal to noise, S/N=3).
Mental models and transformative learning: The key to leadership development?
Authors: Johnson Homer H.
Published: March 2008

What separates successful leaders from unsuccessful ones is their mental models or meaning structures, not their knowledge, information, training, or experience per se. Thus the development of leaders should focus on acquisition of new mental models, models that offer more valid and useful ways for effectively dealing with the complex challenges of leadership. This article describes a process, based on transformative learning, that seems to be the key to assisting leaders in acquiring more useful mental models and in turn becoming more effective leaders.
Detection and identification of optical activity using polarimetry – applications to biophotonics, biomedicine and biochemistry
Authors: Bahar Ezekiel
Published: March 2008

Polarized light that is reflected or transmitted through chiral specimens can be used to detect and identify biological and chemical materials including human tissue. The determination of the silent footprints of the chiral properties of the biological materials on scattered polarized light is the basis for these investigations. It is of primary importance to identify which combinations of the elements of the Mueller matrix for reflected or for transmitted light can be used to determine the optical activity of the biochemical materials. The optical activity of chiral materials is characterized by optical rotation and circular dichroism. The explicit analytical dependence of these specific elements of the Mueller matrix, upon the angles of incidence and scatter, upon the wavelength and upon the type of chirality has the potential to provide experimentalists with guidance in determining the optimum use of optical polarimetric scatterometers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integrin α5‐induced EGFR activation by prothrombin triggers hepatocyte apoptosis via the JNK signaling pathway
Authors: Wang Ziqiu , Wang Meifang , Carr Brian I.
Published: March 2008

We have previously shown that prothrombin, a blood coagulation factor, can cause an inhibition of DNA synthesis in normal rat hepatocytes. To explore the mechanisms of this prothrombin action, we examined its effects on the activation of fibronectin receptor integrin α5, since fibronectin was found to be degraded by prothrombin actions in primary hepatocyte cultures. We found that prothrombin treatment of rat hepatocytes without addition of any growth factor induced tyrosine phosphorylation of integrin α5 and interaction of integrin α5 with epidermal growth factor receptor (EGFR), leading to EGFR tyrosine phosphorylation at tyrosine residues Tyr‐845 and Tyr‐1173. EGFR tyrosine phosphorylation triggered phosphorylation of its down‐stream target Shc and the activation of the c‐Jun N‐terminal kinase (JNK) pathway. Prothrombin also induced hepatocyte apoptosis, a change in cell shape and activation of caspase 3 pathway. The JNK pathway is most likely involved in prothrombin‐induced hepatocyte apoptosis, because pre‐treatment of hepatocytes with JNK kinase inhibitor II (SP600125) antagonized these prothrombin actions. The data suggest that integrin‐related EGFR activation by prothrombin can induce cell growth inhibition and apoptosis via an EGFR‐JNK signaling pathway. J. Cell. Physiol. 216: 551–557, 2008. © 2008 Wiley‐Liss, Inc.
The geodiamolide H, derived from brazilian sponge Geodia corticostylifera, regulates actin cytoskeleton, migration and invasion of breast cancer cells cultured in three‐dimensional environment
Authors: Freitas Vanessa M. , Rangel Marisa , Bisson Letícia F. , Jaeger Ruy G. , Machado‐Santelli Gláucia M.
Published: March 2008

We are investigating effects of the depsipeptide geodiamolide H, isolated from the Brazilian sponge Geodia corticostylifera, on cancer cell lines grown in 3D environment. As shown previously geodiamolide H disrupts actin cytoskeleton in both sea urchin eggs and breast cancer cell monolayers. We used a normal mammary epithelial cell line MCF 10A that in 3D assay results formation of polarized spheroids. We also used cell lines derived from breast tumors with different degrees of differentiation: MCF7 positive for estrogen receptor and the Hs578T, negative for hormone receptors. Cells were placed on top of Matrigel. Spheroids obtained from these cultures were treated with geodiamolide H. Control and treated samples were analyzed by light and confocal microscopy. Geodiamolide H dramatically affected the poorly differentiated and aggressive Hs578T cell line. The peptide reverted Hs578T malignant phenotype to polarized spheroid‐like structures. MCF7 cells treated by geodiamolide H exhibited polarization compared to controls. Geodiamolide H induced striking phenotypic modifications in Hs578T cell line and disruption of actin cytoskeleton. We investigated effects of geodiamolide H on migration and invasion of Hs578T cells. Time‐lapse microscopy showed that the peptide inhibited migration of these cells in a dose‐dependent manner. Furthermore invasion assays revealed that geodiamolide H induced a 30% decrease on invasive behavior of Hs578T cells. Our results suggest that geodiamolide H inhibits migration and invasion of Hs578T cells probably through modifications in actin cytoskeleton. The fact that normal cell lines were not affected by treatment with geodiamolide H stimulates new studies towards therapeutic use for this peptide. J. Cell. Physiol. 216: 583–594, 2008, © 2008 Wiley‐Liss, Inc.
The effect of solvents on the rate of catalytic hydrogenation of 6‐ethyl‐1,2,3,4‐tetrahydroanthracene‐9,10‐dione
Authors: Fajt Vojtěch , Kurc Ladislav , Červený Libor
Published: March 2008

The rate of hydrogenation of 6‐ethyl‐1,2,3,4‐tetrahydroanthracene‐9,10‐dione was investigated at 313 K and 0.1 MPa in 20 solvents. A multiple linear regression was used to describe the solvent effect. The regression of the reaction rates was carried out using two five‐parameter linear regression models: the Abraham–Kamlet–Taft (AKT) and the Koppel–Palm (KP) model. After the elimination of the insignificant terms from the regression models, it was found that the basic character of the solvent and its Hildebrand cohesion energy density were the most important attributes influencing the hydrogenation rate. The analysis of both models led to the same conclusion. The resultant simplified AKT model gave closer fitting in comparison to the KP model. The results could facilitate the solvent selection for the industrial process of hydrogen peroxide production by the anthraquinone method with respect to the kinetics of anthraquinone hydrogenation. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 240–252, 2008
Micellar effect on quinquivalent vanadium ion oxidation of D‐glucose in aqueous acid media: A kinetic study
Authors: Saha Bidyut , Sarkar Sucharita , Chowdhury Kiran M.
Published: March 2008

Vanadium(V) oxidation of D‐glucose shows first‐order dependence on D‐glucose, vanadium(V), H+, and HSO. These observations remain unaltered in the presence of externally added surfactants. The effect of the cationic surfactant (i.e., N‐cetylpyridinium chloride [CPC]), anionic surfactant (i.e., sodium dodecyl sulfate [SDS]), and neutral surfactant (i.e., Trion X‐100 [TX‐100]) has been studied. CPC inhibits the reactions, whereas SDS and TX‐100 accelerate the reaction to different extents. Observed effects have been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 282–286, 2008
Pulse compression techniques using highly nonlinear fibers
Authors: Inoue T. , Namiki S.
Published: March 2008

We review optical pulse compression techniques based on optical fibers. After discussing the fundamental issues on pulse compression, we summarize and categorize various kinds of techniques for pulse compression. We then focus on the use of highly nonlinear fiber (HNLF) in a pulse compressor to improve the performance. Introducing a figure of merit, we discuss which kind of HNLF of those recently reported is the most suitable for applications to pulse compression. As a HNLF‐based optical pulse compressor, we review the technologies of the comb‐like profiled fiber (CPF) which consists of alternate concatenations of HNLF and single‐mode fiber. Discussing the features of CPF, we show that CPF is a truly practical and flexible solution for optical pulse compression. Finally, we refer to a new class of pulse compression called “the stationary rescaled pulse (SRP)”, which is a characteristic nonlinear stationary pulse propagating through CPF. The propagation characteristics of the SRP provides a systematic and efficient design method of CPF as well as optical pulse compression that has never been achieved by conventional pulse compression schemes. As an example, a highly steep pulse compression in CPF is demonstrated, where a pulse is compressed by a factor of 2.1 per step of the CPF, and a 7.2 ps‐width optical pulse is compressed to 0.38 ps with a four‐step structure of CPF.
Recent progress in multiphoton microfabrication
Authors: Maruo S. , Fourkas J.T.
Published: March 2008

Multiphoton microfabrication enables the production of three‐dimensional microstructures with sub‐100 nm resolution via direct laser writing using a femtosecond, pulsed laser beam. The range of materials available for multiphoton processing has increased steadily over the past decade, and the extent of potential applications has increased correspondingly. Current application areas include photonics, microelectromechanical systems, and microelectronics. We review the fundamentals of multiphoton microfabrication and recent progress on materials and applications. Approaches for the mass production of three‐dimensional structures created with multiphoton fabrication are also discussed.
A completeness theorem for a dissipative Schrödinger problem with the spectral parameter in the boundary condition
Authors: Ongun M. Yakít , Allahverdiev Bilender P.
Published: March 2008

In this paper we consider a dissipative Schrödinger boundary value problem in the limit‐circle case with the spectral parameter in the boundary condition. The approach is based on the use of the maximal dissipative operator, and the spectral analyzes of this operator is adequate for the boundary value problem to be solved. We construct a self‐adjoint dilation of the maximal dissipative operator and its incoming and outgoing spectral representations, which make it possible to determine the scattering matrix of the dilation. We also construct a functional model of the maximal dissipative operator and define its characteristic function in terms of solutions of the corresponding Schrödinger equation. We prove theorems on the completeness of the system of eigenvectors and associated vectors of the maximal dissipative operator and the Schrödinger boundary value problem. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modulation of steroid activity in chronic inflammation: A novel anti‐inflammatory role for curcumin
Authors: Biswas Saibal , Rahman Irfan
Published: March 2008

This article has been retracted due to a substantial overlap with a previously published article in another journal.
Structure–property relationships of low dielectric constant, nanoporous, thermally stable polyimides via grafting of poly(propylene glycol) oligomers
Authors: Mehdipour‐Ataei Shahram , Saidi Samaneh
Published: March 2008

Synthesis of high temperature polyimide foams with pore sizes in the nanometer range was developed. Foams were prepared by casting graft copolymers comprising a thermally stable block as the matrix and a thermally labile material as the dispersed phase. The copolyimides as the matrix material were prepared via polycondensation reactions of pyromellitic dianhydride with three new diamines (4BAP, 3BAP, and BAN) through the poly(amic acid) precursors. Functionalized poly(propylene glycol) (PPGBr‐1000 and PPGBr‐2500) as the labile oligomer was prepared via reaction of poly(propylene glycol) monobutyl ether with 2‐bromoacetyl bromide. Graft copolymers were prepared by the reaction of the poly(amic acid)s with these thermally labile constituents. Upon thermal treatment the labile blocks were subsequently removed leaving pores with the size and shape of the original copolymer morphology. The polyimides and foamed polyimides were characterized by some conventional methods including FTIR, H‐NMR, DSC, TGA, SEM, TEM, and dielectric constant. The average pore size of the polyimide nanofoams was in the range of 5–20 nm. The structure–property relationships of the prepared nanofoams were investigated based on the diamine structures and also molecular weights of labile groups. Copyright © 2008 John Wiley & Sons, Ltd.
Twin–twin transfusion syndrome: mathematical modelling
Authors: van den Wijngaard Jeroen P. H. M. , Umur Asli , Ross Michael G. , van Gemert Martin J. C.
Published: March 2008

Twin–twin transfusion syndrome (TTTS) represents a pregnancy complication with a high risk for perinatal mortality and postnatal morbidity. Mathematical models have been utilized to examine the mechanisms of disease and potential treatment modalities. We developed four consecutive models based on pathophysiology mechanisms. Conceptually, these models remained simple, but with increased complexity in details. We present our models tutorially with the necessary equations expressed in words. The aetiology of TTTS was related to AV anastomoses from donor to recipient and their growth commensurate with placental growth. We assessed that natural growth of placenta and foetuses causes the diameter and length of the AV, as well as the AV's pressure gradient, to increase proportional to gestational age. The AV transfusion then increases faster than natural foetal growth. A progressively increasing discordance subsequently develops, not compensated for by foetal growth. A simulation is performed to show how this discordance in blood volumetric development causes successive discordances in other functions, particularly renal, circulatory, and cardio‐vascular, resulting in disease progression to the various stages of TTTS. In conclusion, mathematical modelling of TTTS has provided an understanding of the sequence of events that leads to the various presentations of TTTS stages as well as the efficacy of therapies. Copyright © 2008 John Wiley & Sons, Ltd.
Laser coagulation of placental anastomoses with a 30° fetoscope in severe mid‐trimester twin–twin transfusion syndrome with anterior placenta
Authors: Huber A. , Baschat A. A. , Bregenzer T. , Diemert A. , Tchirikov M. , Hackelöer B. J. , Hecher K.
Published: March 2008

Objective

To assess outcome after fetoscopic laser coagulation (FLC) of placental vascular anastomoses with the 30° fetoscope in mid‐trimester severe twin‐to‐twin transfusion syndrome (TTTS) with completely anterior placenta compared with the regular 0° fetoscope in TTTS with other placental locations.

Methods

This was a prospective study of 176 consecutive monochorionic twin pregnancies undergoing FLC for severe TTTS. Of these, 51 patients required use of the 30° fetoscope (study group) and 125 placental locations permitted use of the 0° fetoscope (controls).

Results

The two groups had very similar outcomes. The median gestational age at FLC in the study group vs. control group was 21.0 (range, 17.4–24.6) weeks vs. 20.6 (range, 15.9–24.6) weeks. Both fetuses survived in 58.8% (30/51) of study patients vs. 66.4% (83/125) of controls. At least one fetus survived in 84.3% (43/51) of study patients and 88.8% (111/125) of controls (P = 0.45). Study patients delivered at a median of 34.1 (range, 25.0–38.4) weeks and controls at 34.0 (range, 25.0–40.3) weeks' gestation.

Conclusions

Use of a 30° fetoscope for FLC in cases of technically challenging extensive anterior placentation is associated with an outcome that is very similar to that achieved when a 0° fetoscope is used in cases of more favorable placental location. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Assessment of aerosol particles within the Rubens' House Museum in Antwerp, Belgium
Authors: Godoi Ricardo Henrique Moreton , Potgieter‐Vermaak Sanja , Godoi Ana Flavia Locateli , Stranger Marianne , Van Grieken Rene
Published: March 2008

The majority of researchers, conservators and curators recognise that atmospheric pollution is one of the major threats to works of art. In principle, all atmospheric particles, when deposited onto art objects can be considered harmful because of their potential in causing deterioration. Moreover, under certain conditions, particulate matter can induce and intensify surface damage, particularly because of its potential to serve as centre for moisture condensation and adsorbent of gaseous pollutants. To investigate the potential harm that these particles can cause, comprehensive characterisation of the particulate matter is necessary. Particulate matter was collected at the Rubens' House Museum in Antwerp, Belgium, where a unique exhibit of the paintings and living quarters of Peter Paul Rubens (1577–1640) are seen. Size segregated aerosol samples were collected for analyses of bulk and single particle elemental and molecular compositions. They were analysed by electron probe micro‐analysis, utilising facilities for low‐Z element determination, and by energy‐dispersive x‐ray fluorescence, to investigate the elemental composition of individual particles and bulk samples, and by micro Raman spectrometry, to elucidate the molecular composition. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could contribute to the chemical reactions taking place on the surfaces of artefacts and which could potentially cause degradation of the objects. Copyright © 2008 John Wiley & Sons, Ltd.
The Saccharomyces cerevisiae CLB5 promoter contains two middle sporulation elements (MSEs) that are differentially regulated during sporulation
Authors: Raithatha Sheetal A. , Stuart David T.
Published: March 2008

The B‐type cyclins Clb5 and Clb6 are essential activators of DNA replication during sporulation in Saccharomyces cerevisiae. The expression of CLB5 is maximally induced during the middle phase of sporulation by the transcription factor Ndt80. We have performed an analysis of the CLB5 promoter and have identified two middle sporulation elements (MSEs) that act as binding sites for Ndt80. Although both MSE sequences bind Ndt80 in vitro, they display differential effectiveness in their ability to function as cis‐acting regulatory sequences in vivo. Mutation of both MSE sequences in the CLB5 promoter profoundly reduces the induction of CLB5 transcription during the middle phase of sporulation but results in no obvious defect in progression through meiosis and sporulation, implying that the Ndt80‐dependent induction of CLB5 is not required for effective DNA replication or chromosome division. Copyright © 2008 John Wiley & Sons, Ltd.
Development of a transformation and selection system for the glycolipid‐producing yeast Candida bombicola
Authors: Van Bogaert Inge N. A. , De Maeseneire Sofie L. , Develter Dirk , Soetaert Wim , Vandamme Erick J.
Published: March 2008

Sophorolipids are surface‐active compounds synthesized by the non‐pathogenic yeast Candida bombicola. Over recent decades much effort has been spent to optimize culture conditions in order to improve the yield and production process. As far as we know, however, hardly any attention has been given to the genetics of the producing yeast strain itself and there are no published results available on the genetic engineering of C. bombicola. Nevertheless, this can be a useful tool for the study of the sophorolipid synthesis pathway and open up perspectives for improved production. A first step is the development of a suitable transformation and selection method. This article describes the creation and selection of an uracil auxotrophic C. bombicola mutant, which can be transformed back to prototrophy with the species' own orotidine 5′‐phosphate decarboxylase or URA3 gene. Successful transformation was confirmed by a PCR‐based method discriminating between the wild‐type and mutated URA3 gene. Copyright © 2008 John Wiley & Sons, Ltd.
Regulation of cell structure and function by actin‐binding proteins: Villin's perspective
Authors: Khurana Seema , George Sudeep P.
Published: March 2008

Villin is a tissue‐specific actin modifying protein that is associated with actin filaments in the microvilli and terminal web of epithelial cells. It belongs to a large family of actin‐binding proteins which includes actin‐capping, ‐nucleating and/or ‐severing proteins such as gelsolin, severin, fragmin, adseverin/scinderin and actin crosslinking proteins such as dematin and supervillin. Studies done in epithelial cell lines and villin knock‐out mice have demonstrated the function of villin in regulating actin dynamics, cell morphology, epithelial‐to‐mesenchymal transition, cell migration and cell survival. In addition, the ligand‐binding properties of villin (F‐actin, G‐actin, calcium, phospholipids and phospholipase C‐γ1) are mechanistically important for the crosstalk between signaling pathways and actin reorganization in epithelial cells.
Homocysteine activates calcium‐mediated cell signaling mechanisms targeting the cytoskeleton in rat hippocampus
Authors: Loureiro Samanta Oliveira , Heimfarth Luana , Pelaez Priscila de Lima , Vanzin Camila Simioni , Viana Lilian , Wyse Angela T.S. , Pessoa‐Pureur Regina
Published: March 2008

Homocysteine is considered to be neurotoxic and a risk factor for neurodegenerative diseases. Despite the increasing evidences of excitotoxic mechanisms of homocysteine (Hcy), little is known about the action of Hcy on the cytoskeleton. In this context, the aim of the present work was to investigate the signaling pathways involved in the mechanism of action of Hcy on cytoskeletal phosphorylation in cerebral cortex and hippocampus of rats during development. Results showed that 100 μM Hcy increased the intermediate filament (IF) phosphorylation only in 17‐day‐old rat hippocampal slices without affecting the cerebral cortex from 9‐ to 29‐day‐old animals. Stimulation of45Ca2+uptake supported the involvement of NMDA receptors and voltage‐dependent channels in extracellular Ca2+flux, as well as Ca2+release from intracellular stores through inositol‐3‐phosphate and ryanodine receptors. Moreover, the mechanisms underlying the Hcy effect on hippocampus cytoskeleton involved the participation of phospholipase C, protein kinase C, mitogen‐activated protein kinase, phosphoinositol‐3 kinase and calcium/calmodulin‐dependent protein kinase II. The Hcy‐induced IF hyperphosphorylation was also related to Giprotein and inhibition of cAMP levels. These findings demonstrate that Hcy at a concentration described to induce neurototoxicity activates the IF‐associated phosphorylating system during development in hippocampal slices of rats through different cell signaling mechanisms. These results probably suggest that hippocampal rather than cortical cytoskeleton is succeptible to neurotoxical concentrations of Hcy during development and this could be involved in the neural damage characteristic of mild homocystinuric patients.
Formulation of a strategy for the application of Duddingtonia flagrans to control caprine parasitic gastroenteritis
Authors: Sanyal P.K. , Sarkar A.K. , Patel N.K. , Mandal S.C. , Pal S.
Published: March 2008

Experiments on the influence of egg density and varying quantities of chlamydospores on the nematode-trapping ability of Duddingtonia flagrans, influence of D. flagrans on the larval translation of gastrointestinal nematodes, doses of chlamydospores required for the effective control of gastrointestinal nematodosis and the epidemiology of nematode parasites were conducted in goats, which generated baseline data required for strategic application of the biocontrol agent. The nematode-trapping ability of D. flagrans, measured by numerical enumeration of infective third-stage larvae developed in the faecal culture, revealed that the efficacy is dependent on both nematode egg and chlamydospore density. Pasture plot studies revealed that D. flagrans, if deposited at the same time as nematode eggs, prevents translation of third-stage larvae of caprine nematodes from the faecal pats onto the grass blades. Feeding of 1 × 106 chlamydospores per kg body weight and above to goats virtually eliminated larvae from the pasture. Application of as few as 1 × 104 and 1 × 105 chlamydospores per kg body weight had a profound impact on larval recovery. The effect persisted as long as the chlamydospores were fed. Monthly faecal worm egg counts of adult goats maintained under a semi-intensive management system on the Chhattisgarh plain and pasture larval burden revealed that June to August were the months of high risk for nematodosis. Haemonchus was the dominant species recorded throughout the year. The present data can best be utilized by formulating a strategic control measure when the larval challenge to the animal is maximum (June to August), so as to prevent establishment of patent infection. The observations reinforced the strategy to be adopted for nematode parasite control in goats by applying the biocontrol option at the onset of the monsoon.
How will public and animal health interventions drive life-history evolution in parasitic nematodes?
Authors: LYNCH PENELOPE A. , GRIMM UWE , READ ANDREW F.
Published: March 2008

Infection caused by parasitic nematodes of humans and livestock can have significant health and economic costs. Treatments aimed at alleviating these costs, such as chemotherapy and vaccination, alter parasite survival and reproduction, the main selective pressures shaping life-history traits such as age to maturity, size and fecundity. Most authors have argued that the life-history evolution prompted by animal and public health programmes would be clinically beneficial, generating smaller, less fecund worms, and several mathematical models support this view. However, using mathematical models of long-lasting interventions, such as vaccination, and regularly repeated short interventions, such as drenching, we show here that the expected outcome actually depends on how mortality rates vary as a function of worm size and developmental status. Interventions which change mortality functions can exert selection pressure to either shorten or extend the time to maturity, and thus increase or decrease worm fecundity and size. The evolutionary trajectory depends critically on the details of the mortality functions with and without the intervention. Earlier optimism that health interventions would always prompt the evolution of smaller, less fecund and hence clinically less damaging worms is premature.
A new class of isotropic generators for developing 6-DOF isotropic manipulators
Authors: Tsai K. Y. , Lee T. K. , Jang Y. S.
Published: March 2008

Developing 6-DOF isotropic manipulators using isotropic generators is simple and efficient, and isotropic generators can be employed to develop serial, redundant, or parallel isotropic manipulators. An isotropic generator consists of a reference point and six straight lines. The existing generators, however, have one common geometric constraint: the reference point is equidistant from the six straight lines. Some practical isotropic designs might not be obtained due to this constraint. This paper proposes methods for developing new isotropic generators. The generators thus developed are not subject to the constraint, and the new methods allow us to specify the location of the tool center point, the size of the platform or the base, or the shape of isotropic parallel manipulators. Many new generators are presented to develop 6-DOF parallel manipulators with different shapes or different types of kinematic chains.
Inhalant abuse among adolescents: neurobiological considerations
Authors: Lubman D I , Yücel M , Lawrence A J
Published: March 2008

Experimentation with volatile substances (inhalants) is common during early adolescence, yet limited work has been conducted examining the neurobiological impact of regular binge use during this key stage of development. Human studies consistently demonstrate that chronic use is associated with significant toxic effects, including neurological and neuropsychological impairment, as well as diffuse and subtle changes in white matter. However, most preclinical research has tended to focus on acute exposure, with limited work examining the neuropharmacological or toxicological mechanisms underpinning these changes or their potential reversibility with abstinence. Nevertheless, there is growing evidence that commonly abused inhalants share common cellular mechanisms, and have similar actions to other drugs of abuse. Indeed, the majority of acute behavioural effects appear to be underpinned by changes in receptor and/or ion channel activity (for example, GABAA, glycine and 5HT3receptor activation, NMDA receptor inhibition), although nonspecific interactions can also arise at high concentrations. Recent studies examining the effects of toluene exposure during the early postnatal period are suggestive of long‐term alterations in the function of NMDA and GABAAreceptors, although limited work has been conducted investigating exposure during adolescence. Given the critical role of neurotransmitter systems in cognitive, emotional and brain development, future studies will need to take account of the substantial neuromaturational changes that are known to occur in the brain during childhood and adolescence, and to specifically investigate the neuropharmacological and toxicological profile of inhalant exposure during this period of development.

British Journal of Pharmacology(2008)154, 316–326; doi:10.1038/bjp.2008.76; published online 10 March 2008
Photodynamic activity of BAM‐SiPc, an unsymmetrical bisamino silicon(IV) phthalocyanine, in tumour‐bearing nude mice
Authors: Leung S C H , Lo P‐C , Ng D K P , Liu W‐K , Fung K‐P , Fong W‐P
Published: March 2008

Background and purpose: Ever since the discovery of photodynamic therapy, there has been a continuous search for more potent photosensitizers. Towards that end, we have synthesized a number of novel phthalocyanine derivatives. The unsymmetrical bisamino silicon(IV) phthalocyanine BAM‐SiPc is one of the most potent compounds. In in vitro cell culture, it exhibits high phototoxicity against a number of cancer cell lines.

Experimental approach: In the present investigation, the in vivo effect of BAM‐SiPc was studied in the tumour‐bearing nude mice model. The biodistribution of BAM‐SiPc was followed to evaluate its tumour selectivity and rate of clearance. The tumour volume in the hepatocarcinoma HepG2‐ and the colorectal adenocarcinoma HT29‐bearing nude mice was measured after photodynamic therapy. The level of intrinsic toxicity induced was also investigated. Finally, the metabolism of BAM‐SiPc in the ‘normal’ WRL68 liver cells and the hepatocarcinoma HepG2 cells was compared.

Key results: The results not only showed significant tumour regression of HepG2 and growth inhibition of HT29 in the tumour‐bearing nude mice, but also no apparent hepatic or cardiac injury with the protocol used. Histological analyses showed that apoptosis was induced in the solid tumour. BAM‐SiPc could be metabolized by WRL68 liver cells but not by the hepatocarcinoma HepG2 cells. Unfortunately, BAM‐SiPc did not show any specific targeting towards the tumour tissue.

Conclusions and implications: The efficiency of BAM‐SiPc in inhibiting tumour growth makes it a good candidate for further evaluation. Enhancement of its uptake in tumour tissue by conjugation with biomolecules is currently under investigation.
Faecal Aeromonas spp. in Balinese children
Authors: SANTOSO HENDRA , AGUNG I. G. N. , ROBINSON JENNIFER , GRACEY MICHAEL
Published: March 2008

Abstract Aeromonas species were found in the faeces of 15.5% of Balinese children with diarrhoea and 12.7% of children without diarrhoea. When only the strains which produce cytotoxic enterotoxin are considered, the isolation rate in the group with diarrhoea (7.1%) was more than twice that in the control group (2.8%). The predominant species was A. hydrophila, a strain associated with environmental sources. Faecal isolates found in Bali may reflect ingestion of contaminated water and may simply be transient. Further studies are needed to clarify the importance of Aeromonas species as an enteric pathogen in developing countries.
Hepatocellular carcinoma not associated with cirrhosis. A clinicopathological study in 41 patients including 29 resected cases
Authors: OKUDA HIROAKI , OBATA HIROSHI , SAITO AKIKO , TOMIMATSU MASAHIKO , HISAMITSU TOJU , TAKASAKI TAKESHI , KOBAYASHI SEIICHIRO
Published: March 2008

Abstract Clinicopathological features were studied in 41 patients with histology‐proven hepatocellular carcinoma without cirrhosis. Of these, 13 (31.7%) were positive for hepatitis B virus surface antigen (HBsAg) and 28 were negative. Twenty‐six of 28 (92.9%) HBsAg negative cases had anticore antibody (anti‐HBc) of low titres. The age of patients at the time of diagnosis of hepatocellular carcinoma was significantly younger in the HBsAg positive cases compared with the negative. The initial diagnostic clue was either abdominal mass or abdominal pain in 18 (43.9%) patients. However, the number of patients in whom hepatocellular carcinoma was detected by imaging in the absence of such clinical signs has increased recently. The tumour was encapsulated in 31 cases (75.6%) and most solitary encapsulated tumours were growing expansively. Tumours were resectable in 29 (70.7%) cases, and the prognosis of resected cases was much better than that of 12 non‐operated cases. Twenty‐one out of 29 (72.4%) resected tumours were solitary and encapsulated. However, recurrence of tumour occurred in 12 out of 28 (42.9%) cases, and it was within 2 years of resection in 11 cases. These observations and data seem to indicate that early detection and resection of tumour is very important in management, but tumour recurrence is inevitable in a considerable proportion of the patients with non‐cirrhotic hepatocellular carcinoma.
Sphincter of Oddi motor activity in patients with stones in gall‐bladder, common bile duct or intrahepatic duct and the effect of morphine
Authors: MATSUMOTO SHINJI , TANAKA MASAO , IKEDA SEIYO , YOSHIMOTO HIDEO , NAKAYAMA FUMIO , Matsumoto S. , Tanaka M. , Ikeda S. , Yoshimoto H. , Nakayama F.
Published: March 2008

Abstract Sphincter of Oddi phasic motor activity and common bile duct pressure were investigated in controls (seven patients) and in patients with gall‐bladder stones (five patients), common bile duct stones (15 patients), or intrahepatic stones (13 patients). There were no significant differences in amplitude and frequency of the phasic activity or the common bile duct pressure between the controls and disease groups. Basal pressure of the phasic contraction, however, was significantly lower in patients with common bile duct or intrahepatic stones than in the controls or gall‐bladder stone group. The administration of morphine, known to cause spasm of the sphincter of Oddi, increased the basal pressure and frequency of the phasic waves in all groups, while the amplitude remained unchanged. Response to morphine in patients with common bile duct or intrahepatic stones was similar to the controls. However, the basal pressure in these latter groups was lower than in the controls, even after stimulation by morphine. The high incidence of bacterial growth in bile from these patients hitherto reported may be attributable to ascending infection possibly resulting from the low basal pressure of the sphincter of Oddi.
The role of the liver in the metabolism of neurotensin‐like immunoreactivity in man and dog
Authors: EAVES E. R. , HANSKY J. , CAHILL C. M. , WARD F. , MERCURI J. , MCLEAN A. J.
Published: March 2008

Abstract To assess the role of liver in the metabolism of neurotensin‐like immunoreactivity (NTLI) basal and meal‐stimulated levels of plasma NTLI were measured by radioimmunoassay, employing a specific C‐terminal antiserum in: healthy control subjects; patients with cirrhosis of the liver who had previously undergone a portacaval shunt; and patients with cirrhosis of the liver and hepatic failure, without a portacaval shunt. Neurotensin (1–13) was infused into the portal vein of the dog for 60 min, at a dose of 100 pmol/kg per min, and blood sampled simultaneously from the portal, hepatic and peripheral venous systems to determine the hepatic extraction and clearance of NTLI. The results revealed that: the liver is a major site of neurotensin metabolism; transhepatic extraction of exogenous neurotensin was 39%; hepatic clearance of NTLI was about 13 ml/kg per min and the total metabolic clearance of NTLI was 36.8 ml/kg per min (s.e.m. = 4.8) and the t½ of NTLI was 2.8 min.
Aeromonas species in human diarrhoeal disease
Authors: BURKE VALERIE , GRACEY MICHAEL
Published: March 2008

Abstract Aeromonas spp. have been reported in association with episodes of diarrhoeal illnesses over many years yet they have not been generally accepted as enteric pathogens for humans. Studies of potential virulence factors produced by Aeromonas species indicate mechanisms by which these bacteria may cause diarrhoea.
New approaches to the diagnosis of functional upper gut disease
Authors: Camilleri Michael
Published: March 2008

AbstractFunctional upper gut symptoms, such as nausea, vomiting and abdominal pain, are a continuing challenge in gastroenterological practice. This article considers the approaches applied in recent years to evaluate motor function in the upper gut including manometry and radio‐nuclide transit studies, and symptom‐provocation tests such as balloon distension and pharmacologic stimulation.

An approach is proposed that is based on positive symptomatic diagnosis of the disturbed pathophysiologic state, followed by treatment of this disturbance of function after a minimum of confirmatory investigations.
The effect of omeprazole on 24 h intragastric pH and fasting plasma gastrin during low dosage (10 mg) in the morning or the evening
Authors: PRICHARD P. J. , YEOMANS N. D. , SHULKES A. , JONES D. B. , BUCKLE P. J. , SMALLWOOD R. A. , LOUIS W. J.
Published: March 2008

Abstract The effect of a low dose of omeprazole on intragastric acidity and fasting plasma gastrin concentration was measured in eight subjects with duodenal ulcer in remission. Intragastric acidity was measured during a baseline 24 h period. This was then repeated after 14 days of dosage with 10 mg of omeprazole administered daily, either in the morning or the evening, using a randomized, double‐blind cross‐over design. The median 24 h pH level rose significantly from a baseline of 1.6, to 3.1 and 3.5 during morning and evening dosages, respectively. However, variability in the response to this dose was substantial: three subjects exhibited no discernible change in 24 h median acidity on two occasions, while in others it was reduced by greater than 99%. Fasting plasma gastrin concentrations were not significantly altered by the administration of 10 mg of omeprazole daily for 2 weeks.
Assessment of disease activity and localization in inflammatory bowel disease using 99mTc‐labelled leucocytes
Authors: BARTHOLOMEUSZ F. D. L. , SHEARMAN D. J. C. , CHATTERTON B. E. , DREW P. A. , HECKER R. , HETZEL D. J. , BAKER R.
Published: March 2008

Abstract Disease activity and regional extent of disease was studied in 20 patients with inflammatory bowel disease (13 with Crohn's disease and seven with ulcerative colitis). Autologous white cells from patients and controls were labelled with 99mTc‐stannous colloid, reinjected, and the faecal excretion of the labelled leucocytes was assessed over 48 h. In patients with Crohn's disease, the faecal excretion correlated with severity of disease as judged by the Harvey‐Bradshaw index. In 18 of the 20 patients the extent of the inflammatory bowel disease as indicated by the scan image corresponded with the radiological and colonoscopic findings. The 99mTc‐stannous colloid label has advantages over indium‐111 and the faecal excretion of labelled leucocytes has potential as a simple, objective measure of disease activity.
In vitro synthesis and immunoregulation of antibody to hepatitis B surface antigen in man
Authors: HANSON REGINALD G. , HOOFNAGLE JAY H. , COOKSLEY W. GRAHAM , JONES E. ANTHONY
Published: March 2008

Abstract Peripheral blood mononuclear cells (PBMC) from 16 chronic hepatitis B surface antigen (HBsAg) carriers and from 10 immune individuals (anti‐HBs and/or anti‐HBc core antigen positive) were studied for their ability to synthesize antibody to hepatitis B viral antigens in vitro. Pokeweed mitogen (PWM)‐stimulated B lymphocytes from carriers, synthesized polyclonal IgG and IgM normally but did not synthesize detectable antibody to HBsAg (anti‐HBs) even in the presence of T lymphocyte help and the absence of T lymphocyte suppression from immune individuals. In contrast, B lymphocytes from 80% of immune individuals synthesized anti‐HBs in vitro. In cell‐mixing experiments, T lymphocytes from carriers were found to provide normal helper function for immunoglobulin and anti‐HBs production by B lymphocytes from immune individuals. In addition, the degree of suppressor T lymphocyte activity of chronic carriers was not sufficient to explain the lack of anti‐HBs production.

The effect of purified HBsAg on anti‐HBs synthesis by PBMC from immune individuals was determined. Incubating PBMC for periods ranging from 10 min to 10 days in the presence of concentrations of HBsAg varying from 10 pg/ml to 10 μg/ml had no effect on the synthesis of anti‐HBs by PBMC. These results suggest that chronic HBsAg carriers lack circulating B lymphocytes capable of producing anti‐HBs and that this cannot be explained by the presence of large amounts of circulating HBsAg.
Familial occurrence of idiopathic portal hypertension: Observations in two sisters
Authors: OHNISHI KUNIHIKO , TSUKAMOTO TOSHIHIKO , GOTO NOBUAKI , SAITO MASAYUKI , TERABAYASHI HIDETAKA , OKUDA KUNIO
Published: March 2008

Abstract Idiopathic (non‐cirrhotic) portal hypertension is one of the major problems in developing countries, but the aetiology is not known. Two sisters with idiopathic portal hypertension diagnosed by percutaneous transhepatic catheterization of the portal vein and liver biopsy are reported. Both patients had large spontaneous portal‐systemic shunts. This seems to be the first report of a familial aggregation of this disorder.