bluuebunny/crossref_metadata_2025 huggingface dataset:
SELDI protein profiling of dunning R‐3327 derived cell lines: Identification of molecular markers of prostate cancer progression
Authors: Malik Gunjan , Rojahn Elizabeth , Ward Michael D. , Gretzer Mathew B. , Partin Alan W. , Semmes O. John , Veltri Robert W.
Published: August 2007

BACKGROUND

We recently demonstrated the protein expression profiling of Dunning rat tumor cell lines of varying metastatic potential (G (0%), AT‐1 (∼20%), and MLL (100%)) using SELDI‐TOF‐MS. As a parallel effort, we have been pursuing the identification of the protein(s) comprising the individual discriminatory “peaks” and evaluating their utility as potential biomarkers for prostate cancer progression.

METHODS

To identify the observed SELDI‐TOF‐MS m/z (mass/charge) values with discriminatory expression between different sublines, we employed a combination of chemical pre‐fractionation, liquid chromatography, gel electrophoresis and tandem mass spectroscopy. Identified proteins were then verified by immuno‐assay and Western analysis.

RESULTS

A 17.5 K m/z SELDI‐TOF‐MS peak was found to retain discriminatory value in each of two separate study‐sets with an increased expression in the metastatic MLL line. Sequence identification and subsequent immunoassays verified that Histone H2B is the observed 17.5 K m/z SELDI peak. SELDI‐based immuno‐assay and Western Blotting revealed that Histone H2B is specifically over‐expressed in metastatic MLL lines.

CONCLUSIONS

SELDI‐TOF MS analysis of the Dunning prostate cancer cell lines confirmed the consistent overexpression of a 17.5 K m/z peak in metastatic MLL subline. The 17.5 kDa protein from MLL has been isolated and identified as Histone H2B. Prostate 67: 1565–1575, 2007. © 2007 Wiley‐Liss, Inc.
Crystal structure and putative function of small Toprim domain‐containing protein from Bacillus stearothermophilus
Authors: Řezáčová Pavlína , Borek Dominika , Moy Shiu F. , Joachimiak Andrzej , Otwinowski Zbyszek
Published: August 2007

The crystal structure of the Midwest Center for Structural Genomics target APC35832, a 14.7‐kDa cytosolic protein from Bacillus stearothermophilus, has been determined at 1.3 Å resolution by the single anomalous diffraction method from a mercury soaked crystal. The APC35832 protein is a representative of large group of bacterial and archeal proteins entirely consisting of the Toprim (topoisomerase‐primase) domain. This domain is found in the catalytic centers of many enzymes catalyzing phosphodiester bond formation or cleavage, but the function of small Toprim domain proteins remains unknown. Consistent with the sequence analysis, the APC35832 structure shows a conserved Toprim fold, with a central 4‐stranded parallel β‐sheet surrounded by four α‐helixes. Comparison of the APC35832 structure with its closest structural homolog, the catalytic core of bacteriophage T7 primase, revealed structural conservation of a metal binding site and isothermal titration calorimetry indicates that APC35832 binds Mg2+ with a sub‐millimolar dissociation constant (Kd). The APC35832–Mg2+ complex structure was determined at 1.65 Å and reveals the role of conserved acidic residues in Mg2+ ion coordination. The structural similarities to other Toprim domain containing proteins and potential function and substrates of APC35832 are discussed in this article. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Cooperative symmetric to asymmetric conformational transition of the apo‐form of scavenger decapping enzyme revealed by simulations
Authors: Pentikäinen Ulla , Pentikäinen Olli T. , Mulholland Adrian J.
Published: August 2007

Decapping is a central step in eukaryotic mRNA turnover and in gene expression regulation. The human scavenger decapping enzyme, DcpS, catalyses cap hydrolysis following mRNA degradation. DcpS is a dimeric enzyme, with two active sites. Crystal structures suggest that DcpS must undergo significant conformational changes upon ligand binding, but the mechanism of this transition is unknown. Here, we report two long timescale (20 ns) molecular dynamics simulations of the apo‐form of DcpS. The dimer is observed to undergo a strikingly cooperative motion, with one active site closing while the other opens. The amplitude of the conformational change is 6–21 Å and the apparent timescale is 4–13 ns. These findings indicate that the crystallographically observed symmetric conformation of apo‐form of DcpS is only a minor conformation in solution. The simulations also show that active sites are structurally connected via the domain‐swapped dimer structure of the N‐terminal domain, even in the absence of a bound ligand. These findings suggest a functional reason for the enzyme existing as a dimer, and may be widely relevant, also for other dimeric proteins. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Quantifying the relationship of protein burying depth and sequence
Authors: Yuan Zheng , Wang Zhi‐Xin
Published: August 2007

Protein burying depth (BD) is a structural descriptor that is exploited not only to find whether a residue is exposed or buried, but also to determine how deep a residue is buried. The widely used solvent accessible surface area is mainly focusing on the study of protein surface residues, while protein BD can provide more detailed information about the arrangement of buried residues, which may be used to study protein deep level structure and the formation of protein folding nucleus. In this work, we analyse the relationship of protein BD and sequences, and describe it by nonlinear functions estimated by support vector machines. We examine the functions by crossvalidation tests and find strong correlation between residue BD and local sequence environment. By further taking account the size of the molecule where a residue is located, we find that the correlation coefficient between predicted and observed depths improves from 0.60 to 0.65. Moreover, nearly half of the deepest 10% residues in a protein sequence can be correctly predicted. Our study suggests that a residue's burying extent is able to be predicted, to some degree, by itself and its local neighbouring residues. The methods used to estimate the sequence‐depth functions are expected to become more useful in the investigation of protein structures and folding mechanism. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Synthesis of SiC nanofibers by microwave plasma assisted chemical vapour deposition in CH4/H2 gas mixture
Authors: Rizk S. , Assouar M. B. , Belmahi M. , Le Brizoual L. , Bougdira J.
Published: August 2007

We report in this study, the growth of silicon carbide nanofibers on silicon substrates covered by Fe thin film catalyst using microwave plasma assisted chemical vapour deposition. The silicon source is the substrate itself. The growth morphology, microstructure, and defects on SiC nanofibers are characterized by field emission scanning electron microscopy and transmission electron microscopy combined with electron energy‐dispersive X‐ray spectroscopy. These characterizations revealed that the resultant fibrous nanostructures, with a diameter of 25–65 nm, were assigned to β‐SiC. Selected area electron diffraction pattern shows a good crystallinity of the obtained nanofibers, and shows that the SiC nanofibers grow along (111) orientation. The formation of SiC nanofibers can be explained by the diffusion of Fe in the silicon substrate due to the high temperature during the process which is around 900 °C. The combination of the etching of the surface by atomic hydrogen and the interaction with carbon radicals and carbon atoms allows then the growth of SiC nanofibers. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High gain observed in X‐ray induced currents in synthetic single crystal diamonds
Authors: Lohstroh A. , Sellin P. J. , Boroumand F. , Morse J.
Published: August 2007

Diamond is considered as tissue equivalent, due to its low atomic number, which makes it a particular attractive material for medical radiation dosimetry applications. X‐ray dosimeters made of natural single crystal diamonds are commercially available and routinely used, with typical gain values of about 0.5. The selection of suitable natural diamonds for this purpose is time and cost intensive. We report an X‐ray induced current study in synthetic single crystal diamonds. Similar to natural diamond dosimeters, the devices had to be pre‐irradiated before use to achieve a reproducible performance. We compare two chemical vapour deposited (CVD) samples grown by Element Six Ltd (UK). D1 was a high purity sample contacted in a sandwich structure with an asymmetric contact pair. Sample D2 was cut vertically and contained some nitrogen rich layers. It was contacted with two Ohmic contacts, which partly covered the high temperature/high pressure substrate material. Particle spectroscopy suggests better charge transport in D1 compared to D2, most likely caused by the lower purity. In contrast to this, large gain values up to 6 × 104 and a sensitivity of ∼30 mC/Gy were measured at field strengths of 2 kV/cm in D2, and only 7 µC/Gy in D1, despite their comparable volumes. We deduce that the gain observed in these devices is affected by the electrical properties of the metal‐diamond contacts. The response time of the high gain device was in the order of minutes, which is longer than expected by a purely photoconductive process. Long persistent currents have been reported before in diamond under UV irradiation and modifications of gain and response time by surface treatment of UV detectors are known in the literature, highlighting the influence of the surface and contact interface on the device operation. Our results indicate that synthetic single crystal diamond provides a promising material for high sensitivity tissue‐equivalent X‐ray dosimeters. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Antiobesity properties of two African plants (Afromomum meleguetta and Spilanthes acmella) by pancreatic lipase inhibition
Authors: Ekanem A. P. , Wang M. , Simon J. E. , Moreno D. A.
Published: August 2007

Ethanol extracts of seeds of Afromomum meleguetta and flower buds of Splilanthes acmella presented pancreatic lipase inhibitory activities in a concentration related manner under in vitro conditions. The two plants were extracted with 70% ethanol by sonication, fractionated on silica gel and tested at concentrations in the range 0.75–2.0 mg/mL. Lipase inhibitory activities of 90% and 40% were observed in A. meleguetta and S. acmella, respectively. The two plants have potentials as candidates for weight reduction and obesity control. Copyright © 2007 John Wiley & Sons, Ltd.
Hepatoprotective effect of leaf extracts of Andrographis lineata nees on liver damage caused by carbon tetrachloride in rats
Authors: Sangameswaran B. , Reddy T. Chandraganth , Jayakar B.
Published: August 2007

The present study was conducted to evaluate the hepatoprotective effect of Andrographis lineata (Acanthaceae) extracts in carbon tetrachloride‐induced liver injury in rats. Male Wistar rats with chronic liver damage, induced by subcutaneous injection of 50% v/v carbon tetrachloride in liquid paraffin at a dose of 3 mL/kg on alternate days for a period of 4 weeks, were treated with methanol and aqueous extracts of A. lineata orally at a dose of 845 mg/kg/day. The biochemical parameters such as serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, serum bilirubin and alkaline phosphatase were estimated to assess the liver function. Histopathological studies of the liver were also carried out to confirm the biochemical changes. Histopathological examinations of liver tissue corroborated well with the biochemical changes. The activities of extracts were comparable to a standard drug. Hepatic steatosis, hydropic degeneration and necrosis were observed in the carbon tetrachloride treated group, while these were completely absent in the standard and extract treated groups. A. lineata extracts exhibited hepatoprotective action against carbon tetrachloride‐induced liver injury. The present investigation established pharmacological evidence to support the folklore claim that it is used traditionally as a hepatoprotective agent. Copyright © 2007 John Wiley & Sons, Ltd.
Schizandrin reverses memory impairment in rats
Authors: Egashira Nobuaki , Kurauchi Kouji , Iwasaki Katsunori , Mishima Kenichi , Orito Kensuke , Oishi Ryozo , Fujiwara Michihiro
Published: August 2007

The present study investigated the effect of schizandrin, a component of the fruit of Schizandra chinesis Baill (Fructus Schizandrae), on memory impairment in rats. Scopolamine (0.5 mg/kg, i.p.), a non‐selective muscarinic receptor antagonist, markedly impaired spatial memory in an eight‐arm radial maze. A higher dose of scopolamine (3 mg/kg, i.p.) also impaired the passive avoidance response. Schizandrin (1 and 10 mg/kg, p.o.) significantly reversed the scopolamine‐induced impairment of spatial memory. Similarly, schizandrin (1 mg/kg, p.o.) significantly reversed the scopolamine‐induced impairment of the passive avoidance response. Moreover, in mice, schizandrin (1 and 10 mg/kg, p.o.) enhanced tremors induced by oxotremorine, a muscarinic M1 receptor agonist. Taken together these findings suggest that schizandrin reverses scopolamine‐induced memory impairment, in part, by enhancing cholinergic function, and that schizandrin might be useful for treating memory deficits. Copyright © 2007 John Wiley & Sons, Ltd.
In vitro anti‐Helicobacter pylori activity of diallyl sulphides and protocatechuic acid
Authors: Liu Wen‐hu , Hsu Cheng‐chin , Yin Mei‐chin
Published: August 2007

The in vitro inhibitory effects of diallyl disulphide (DADS), diallyl trisulphide (DAT), roselle calyx extract and protocatechuic acid (PA) on the growth of Helicobacter pylori (15 susceptible, 11 clarithromycin‐resistant and 9 metronidazole‐resistant strains) were studied. The inhibition zone was determined after each agent had been heated at 25, 60, 100 °C for 60 min. The minimal inhibitory concentration (MIC) of each agent was determined by the tube dilution assay. The results showed that heat treatment did not affect the anti‐H. pylori activity of DADS, DAT, roselle calyx extract and PA, and the MIC values of these agents against test H. pylori strains were in the range 8–64 mg/L. The time‐kill study assay for DAT and PA at 1× MIC was monitored in Muller Hinton broth supplemented with 10% horse blood or mice stomach homogenate. Both DAT and PA inhibited the growth of all test H. pylori in broth and mice stomach homogenate (p < 0.05); however, the inhibitory effects of these two agents were less in mice stomach homogenate than in broth (p < 0.05). DAT at 4, 6, 8, 10, 12, 14 mg/L and PA at 8, 16, 24, 32, 40, 48 mg/L were used for urease activity assay. These two agents significantly reduced urease activity of test H. pylori strains (p < 0.05), in which DAT and PA at 1× MIC reduced the urease activity of H. pylori to 70% and 40%, respectively. These agents, based on their lower MIC values and heat tolerance, might be useful in the prevention or therapy of H. pylori. Copyright © 2007 John Wiley & Sons, Ltd.
Theanine prevents memory impairment induced by repeated cerebral ischemia in rats
Authors: Egashira Nobuaki , Ishigami Noriko , Pu Fengling , Mishima Kenichi , Iwasaki Katsunori , Orito Kensuke , Oishi Ryozo , Fujiwara Michihiro
Published: August 2007

The present study investigated the neuroprotective effect of γ‐glutamylethylamide (theanine), a component Japanese green tea (Camellia sinensis), on memory impairment induced by twice‐repeated cerebral ischemia in rats. Theanine was injected i.p. immediately after the first occlusion. Theanine (0.3 and 1 mg/kg) significantly prevented the impairment of spatial memory in rats subjected to repeated cerebral ischemia, 7 days after the second reperfusion. Moreover, theanine (1 mg/kg) significantly inhibited the decrease in the number of surviving cells in the hippocampal CA1 field in the same rats. These results suggest that theanine prevents memory impairment induced by repeated cerebral ischemia, in part by protecting against neuronal cell death, and that it might be useful for preventing cerebrovascular disease. Copyright © 2007 John Wiley & Sons, Ltd.
Dynamic dipole polarizabilities of the ground and excited states of confined hydrogen atom computed by means of a mapped Fourier grid method
Authors: Cohen S. , Themelis S. I. , Sen K. D.
Published: August 2007

Accurate theoretical estimates of static and dynamic dipole polarizabilities are reported for the ground and excited states of hydrogen atom confined at the center of a spherical “box” with impenetrable walls using a novel theoretical algorithm that combines the variational–perturbation approach with an appropriately adapted mapped Fourier grid method and uniformly maintains the numerical accuracy. A variation of computed polarizabilities is observed as a function of the number of grid points. However, rapid convergence to their correct values, even far into the anomalous dispersion region, is achieved by an extrapolation procedure to the limit of an infinitely large number of grid points using a small number of the lowest‐order Padé approximants. It is shown that dipole polarizabilities strongly depend upon the electronic state and the radius of confinement. In particular, the static polarizability of 2s state changes sign under strong confinement. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Reactivity of silicon‐doped carbon nanotubes toward small gaseous molecules in the atmosphere
Authors: Guo Guanlun , Wang Fang , Sun Hui , Zhang Dongju
Published: August 2007

The reactivities of the pristine and silicon doped (Si‐doped) single‐walled carbon nanotubes (CNTs) toward small gaseous molecules in the atmosphere, such as formaldehyde, carbon monoxide, and hydrogen sulfide, were studied by performing density functional theory calculations. Compared with the physisorptions on the pristine (8, 0) CNT, these small molecules present strong chemical interactions with the Si‐doped (8, 0) tube. Doping intrinsic CNTs with silicon is expected to be a potential strategy for improving the property of pristine CNTs and expanding the application of CNTs in nanoscience and nanotechnology. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
A polarizable high‐rank quantum topological electrostatic potential developed using neural networks: Molecular dynamics simulations on the hydrogen fluoride dimer
Authors: Houlding S. , Liem S. Y. , Popelier P. L. A.
Published: August 2007

The HF molecule is a simple polar system that serves as a prototype for developing new potentials. Here we build on earlier work [Liem and Popelier, J Chem Phys 2003, 119, 4560] in which a high‐rank multipolar potential was used to simulate liquid HF. That work was the first example of high‐rank multipole moments (up to hexadecapole) being employed in conjunction with multipolar Ewald summation in a molecular dynamics simulation. This potential is now extended with polarization, which is delivered by artificial neural networks. The neural nets predict how atomic multipole moments change as the position of neighboring molecules vary. This novel approach is successfully tested on the HF dimer in vacuum. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Characterization of phenolic compounds in Erigeron breviscapus by liquid chromatography coupled to electrospray ionization mass spectrometry
Authors: Zhang Yufeng , Shi Peiying , Qu Haibin , Cheng Yiyu
Published: August 2007

Erigeron breviscapus is an important herbal drug for the treatment of cardiovascular and cerebral vessel diseases. In this study, phenolic compounds were extracted from the whole plant of E. breviscapus and analyzed by high‐performance liquid chromatography/electrospray ionization mass spectrometry. A total of 53 compounds were identified or tentatively characterized based on their UV and mass spectra. These compounds included caffeoylquinic acids (CQAs), CQA glucosides, malonyl‐CQAs, acetyl‐CQAs, caffeoyl‐2,7‐anhydro‐3‐deoxy‐2‐octulopyranosonic acids (CDOAs), caffeoyl‐2,7‐anhydro‐2‐octulopyranosonic acids (COAs), flavones, flavonols and flavonones. Most of them were reported for the first time from E. breviscapus and nineteen of them belonged to new compounds. The MSn spectra of CQA glucosides were similar to CQAs and they were discriminated by their retention times. No caffeic acid related ions (X, Y and Z) were observed in MSn spectra of acyl‐CQAs compared to those of CQAs. Fragment ions (2,5O−, 3,6O− and 4,6O−) corresponding to ring cleavage were shown in MSn spectra of CDOAs and COAs, characteristic of this class of compounds. The 5,6,7‐trihydroxyl‐substituted flavones were dominant in E. breviscapus. Their [AH]− ions underwent the loss of a molecule of H2O, followed by the loss of CO, which was used to discriminate from other hydroxyl‐substituted flavones. Our results are the first comprehensive analysis of E. breviscapus constituents and will be helpful for the quality control of the herb of E. breviscapus and its related preparations. Copyright © 2007 John Wiley & Sons, Ltd.
Studies of iridoid glycosides using liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: Ren Lingling , Xue Xingya , Zhang Feifang , Wang Yongcan , Liu Yanfang , Li Cunman , Liang Xinmiao
Published: August 2007

Fragmentation pathways of five iridoid glycosides have been studied by using electrospray ionization multi‐stage tandem mass spectrometry (ESI‐MSn). The first‐stage MS data of the five iridoid glycosides were compared. The MS spectra showed that the adduct ions of iridoid glycosides and the formate anion were diagnostic ions to distinguish iridoid glycosides with a carboxyl group at the C‐4 position or an ester group at the C‐4 position. The MS fragmentation pathways of the five iridoid glycosides were also studied. Analyzing the product ion spectra of iridoid glycosides, some neutral losses were observed, such as H2O, CO2 and glucose residues, which were very useful for the identification of the functional groups in the structures of iridoid glycosides. Furthermore, specific loss of one molecule of methyl 3‐oxopropanoate or 3‐oxopropanic acid was firstly discussed, which corresponded to the isomerization of the hemiacetal group in the structure of iridoid aglycone. According to the fragmentation mechanisms and HPLC/MSn data, the structures of five iridoid glycosides in a crude extract of Gardenia jasminoisdes fruit have been identified. Three compounds were compared with standards and the other two were identified as shanzhiside and genipin gentibioside by their MSn data without standard compounds. In order to further validate the veracity of the deduction, genipin gentiobioside was isolated from the extract of Gardenia jasminoisdes fruit using Purification Factory and was further identified by C‐ and H‐NMR. Copyright © 2007 John Wiley & Sons, Ltd.
Using high‐concentration trypsin‐immobilized magnetic nanoparticles for rapid in situ protein digestion at elevated temperature
Authors: Jeng Jingyueh , Lin Mon‐Fang , Cheng Fong‐Yu , Yeh Chen‐Sheng , Shiea Jentaie
Published: August 2007

We describe an innovative approach – using a high concentration of trypsin‐modified magnetic nanoparticles (TMNPs) – for the rapid and efficient digestion of proteins at elevated temperature. The required digestion time could be reduced to less than 10 s. After digestion, the TMNPs were collected magnetically from the sample solution for reuse and the digested peptides were characterized using matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry. Protein digestion was optimized when using the TMNPs (5 µg/µL) at 57°C; a significantly high peptide coverage was achieved for protein identification (e.g., 98% for lysozyme). Although a high concentration of TMNPs was used for digestion, the short digestion time led to much lower amounts of trypsin peptides being produced through self‐digestion. As a result, interference in the mass spectrometric detection of the peptide ions was reduced significantly. Copyright © 2007 John Wiley & Sons, Ltd.
A single glucose derivative suitable for gas chromatography/mass spectrometry and gas chromatography/combustion/isotope ratio mass spectrometry
Authors: Jackson Sarah J. , Waterhouse John S. , Bluck Leslie J. C.
Published: August 2007

The incorporation of stable isotopes improves the assessment of glucose metabolism and, with some researchers using two tracers, 2H‐glucose assessed by gas chromatography/mass spectrometry (GC/MS) and 13C‐glucose by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS), a common derivative for both is advantageous. The most commonly used derivatives for GC/MS are inappropriate for GC/C/IRMS as additional functional groups dilute the label. We therefore considered the suitability of six derivatives for both GC/MS and GC/C/IRMS. Glucose alkylboronates were prepared by adding the appropriate alkylboronic acid (butyl‐ or methylboronic acid) in pyridine to desiccated glucose. The derivatisation was completed by reacting this with either (a) acetic anhydride or trifluoroacetic anhydride (acetate derivatives) or (b) bis(trimethylsilyl)trifluoroacetamide BSTFA (TMS derivatives). All six derivatives were assessed using GC/MS and 13C GC/C/IRMS.

Neither TMS derivative exhibited any signal intensity in the molecular ion, although a M‐15 ion showed good agreement between experimental and theoretical data and, whilst still low in intensity, could be suitable for isotope work. Similarly, none of the acetate derivatives showed any intensity at the molecular ion although three key fragmentation series were identified. The most attractive sequence, initiated by the loss of 1,2 cyclic boronate, resulted in the main fragment ion of interest, m/z 240, corresponding to the fluorinated methylboronate derivate. Minimal carbon and hydrogen atoms are added to this derivative making it an excellent choice for stable isotope work, while proving suitable for analysis by both GC/MS and GC/C/IRMS. Copyright © 2007 John Wiley & Sons, Ltd.
Determination of hydrolytic degradation products of nerve agents by injection port fluorination in gas chromatography/mass spectrometry for the verification of the Chemical Weapons Convention
Authors: Pardasani Deepak , Mazumder Avik , Gupta Arvinda K. , Kanaujia Pankaj K. , Tak Vijay , Dubey Devendra K.
Published: August 2007

Retrospective detection and identification of markers of chemical warfare agents are important aspects of verification of the Chemical Weapons Convention. Alkyl alkylphosphonic acids (AAPAs) and alkylphosphonic acids (APAs) are important markers of nerve agents. We describe the development and optimization of a new gas chromatography/mass spectrometry (GC/MS) injection port fluorination method for the derivatization of AAPAs and APAs. The process involved the injection of acids with trifluoroacetic anhydride in GC/MS, where acids are converted into their corresponding volatile fluorides. Various reaction conditions such as fluorinating agent, injection port temperature and splitless time were optimized. The maximum reaction efficiency of the acids with trifluoroacetic anhydride was observed at 230°C injection port temperature with a splitless time of 2 min. APAs showed best analytical efficiencies at 400°C injection port temperature, while the other conditions were similar to those of AAPAs. The linearities of response for APAs and AAPAs were in the range of 1–25 and 5–100 µg mL−1, respectively, with limits of detection ranging from 500 pg to 800 ng mL−1. Copyright © 2007 John Wiley & Sons, Ltd.
Allowing for uncertainty due to missing data in meta‐analysis—Part 2: Hierarchical models
Authors: White Ian R. , Welton Nicky J. , Wood Angela M. , Ades A. E. , Higgins Julian P. T.
Published: August 2007

We propose a hierarchical model for the analysis of data from several randomized trials where some outcomes are missing. The degree of departure from a missing‐at‐random assumption in each arm of each trial is expressed by an informative missing odds ratio (IMOR). We require a realistic prior for the IMORs, including an assessment of the prior correlation between IMORs in different arms and in different trials. The model is fitted by Monte Carlo Markov Chain techniques. By applying the method in three different data sets, we show that it is possible to appropriately capture the extra uncertainty due to missing data, and we discuss in what circumstances it is possible to learn about the IMOR. Copyright © 2007 John Wiley & Sons, Ltd.
Allowing for uncertainty due to missing data in meta‐analysis—Part 1: Two‐stage methods
Authors: White Ian R. , Higgins Julian P. T. , Wood Angela M.
Published: August 2007

Analysis of a randomized trial with missing outcome data involves untestable assumptions, such as the missing at random (MAR) assumption. Estimated treatment effects are potentially biased if these assumptions are wrong. We quantify the degree of departure from the MAR assumption by the informative missingness odds ratio (IMOR). We incorporate prior beliefs about the IMOR in a Bayesian pattern‐mixture model and derive a point estimate and standard error that take account of the uncertainty about the IMOR. In meta‐analysis, this model should be used for four separate sensitivity analyses which explore the impact of IMORs that either agree or contrast across trial arms on pooled results via their effects on point estimates or on standard errors. We also propose a variance inflation factor that can be used to assess the influence of trials with many missing outcomes on the meta‐analysis. We illustrate the methods using a meta‐analysis on psychiatric interventions in deliberate self‐harm. Copyright © 2007 John Wiley & Sons, Ltd.
On the role of acquisition premium in acquisition research
Authors: Laamanen Tomi
Published: August 2007

Several studies argue that paying high acquisition premia is value destroying for acquirer shareholders. There are studies that have even used the size of premium as a measure of low‐quality decision making. This paper departs from the earlier research and shows that acquisition premia may be justified when target firms' resources are difficult for the market to value. An analysis of a sample of 458 acquisitions demonstrates that although higher premia are paid for R&D‐related assets, the premia do not cause negative abnormal returns. Abnormal returns are more strongly affected by the overall target price levels independent of premia. Copyright © 2007 John Wiley & Sons, Ltd.
Buckling behavior improvement of steel plate shear wall systems
Authors: Sabouri‐Ghomi Saeid , Kharrazi Mehdi H. K. , Mam‐Azizi Salah‐E‐Deen , Sajadi Ramin Asad
Published: August 2007

To improve buckling stability and to prevent early elastic buckling of infill plates, vertical and horizontal plate stiffeners are designed for steel plate shear wall (SPSW) systems. Furthermore, effective design of stiffeners for SPSW systems results in improved structural behavior, such as increase of stiffness, capacity and energy absorption. In this paper, the effect of stiffeners is studied on SPSW structural behavior and consequently a rational method is proposed to determine the minimum required moment of inertia for stiffeners resulting in local buckling mode of the infill plate. The proposed requirement is then compared to results obtained from tests previously conducted, as well as those gained from finite element (FE) analyses performed for this study. Copyright © 2007 John Wiley & Sons, Ltd.
Seismic demand of an RC special moment frame building
Authors: Kim Taewan , Kim Jinkoo
Published: August 2007

Seismic design of a building is usually performed by using a linear static procedure. However, the actual behavior of a building subjected to earthquake is inelastic and dynamic in nature, and inelastic dynamic analysis is required to evaluate the safety of the structure designed by the current design codes. In this study, an RC special moment‐resisting frame building was designed by IBC 2003. Maximum plastic rotation, dissipated energy of some selected members, and the drift demand were calculated to examine whether the inelastic behavior of the building followed the intention of the design code. In addition, the effect of internal moment‐resisting frames (gravity load resisting system) on resisting lateral load was investigated. According to the analysis result, the building designed by IBC 2003 showed the inelastic behavior intended in the code and satisfied the design drift limit. Copyright © 2007 John Wiley & Sons, Ltd.
Selecting transition process for WLAN security
Authors: Hsu Shih‐Feng , Lin Yi‐Bing
Published: August 2007

In wireless local area network (WLAN), a station (STA) accesses the Internet through an access point (AP). When switching from one AP to another, the STA executes the transition process, which may incur long delay and result in force‐termination for real‐time applications. The IEEE 802.11r proposes the fast basic service set (BSS) transition to speed up the transiti on process for a STA moving within the same mobility domain (MD). This scheme requires unique MD assignment so that the STA knows whether it should conduct fast BSS transition process (for intra‐MD scenario) or the expensive initial MD association process (for inter‐MD scenario). However, how to guarantee unique MD identifier (MDID) assignment is not mentioned in the specification. This paper proposes a mechanism for IEEE 802.11r fast transition without using MDID, and therefore eliminates the cost for MDID management. Copyright © 2007 John Wiley & Sons, Ltd.
Three successful pregnancies through dietary management of fructose‐1,6‐bisphosphatase deficiency
Authors: Krishnamurthy V. , Eschrich K. , Boney A. , Sullivan J. , McDonald M. , Kishnani P. S. , Koeberl D. D.
Published: August 2007

Fructose‐1,6‐bisphosphatase (FBPase) deficiency (OMIM 229700) has been characterized as the cause of life‐threatening hypoglycaemia and lactic acidaemia following prolonged fasting. The patient, an adult African‐American woman, presented during the second trimester of her first pregnancy with recurrent episodes of lactic acidaemia and hypoglycaemia. She had recently been admitted to a nearby intensive care unit after presentation with profound hypoglycaemia and lactic acidosis, and was found to be pregnant. The history was remarkable for approximately 30 hospitalizations for hypoglycaemia and acidosis. She had previously undergone liver biopsy at another centre and was diagnosed with a ‘glycogen storage disease’ although no enzyme testing had been done for confirmation. Based on clinical symptoms, a diagnosis of FBPase deficiency was accomplished through gene sequencing, which revealed homozygosity for a panethnic, common mutation, 960/961insG in exon 7. The availability of mutation testing facilitated the confirmation of FBPase deficiency in this patient, obviating liver biopsy for enzyme activity confirmation. The patient underwent three successful pregnancies by strict compliance with dietary management, including nocturnal uncooked cornstarch to manage hypoglycaemia. The pregnancies were complicated by mild gestational diabetes, increased cornstarch requirements, and hypoglycaemia at the time of discharge from the hospital. The three infants had normal birth weights and experienced no complications during the neonatal period. The patient subsequently developed sensorineural hearing loss and early‐onset cognitive impairment, despite compliance with the monitoring and treatment of hypoglycaemia. The experience with multiple pregnancies in this FBPase‐deficient patient provides insight into the management of hypoglycaemia in inherited disorders of gluconeogenesis.
Serum S100B levels in X‐linked adrenoleukodystrophy and Gaucher disease
Authors: Michelakakis H. , Kariyannis C. , Moraitou M. , Dimitriou E. , Sarafidou J. , Papassotiriou I.
Published: August 2007

S100B, a small acidic protein, is a member of a multigenic family of calcium‐modulated proteins. It is mainly produced by astrocytes and the secreted protein, depending on its concentration, can exert either trophic or toxic effects. In humans increased S100B levels have been detected in brain trauma and ischaemia, and neurodegenerative, neurometabolic, inflammatory and psychiatric disease. Serum S100B concentrations have been used as markers of brain disease. In the present study S100B serum levels were determined in patients with the neuroinflammatory disease X‐linked adrenoleukodystrophy (X‐ALD) and in patients with both the acute neuronopathic (type II) and the non‐neuronopathic (type I) types of Gaucher disease (GD). Sixteen X‐ALD patients (10 with the childhood, 4 with the adult cerebral forms, 2 asymptomatic) and 22 Gaucher disease patients (19 type I, 3 type II) were studied. No statistically significant differences were observed between the X‐ALD (median 0.13 μg/L, p=0.191) or Gaucher type I patients (median 0.07 μg/L, p=0.095) and controls of similar age (median 0.10 μg/L, n=22). Serum S100B levels of type II Gaucher disease patients were also within the normal for their age range (patients 0.2, 0.22, 0.65; control median 0.81 μg/L, n=44). Lack of clinical symptoms and/or MRI findings in X‐ALD patients was not associated with lower S100B values. Our results indicate that serum S100B levels cannot serve as peripheral marker in the evaluation of brain disease in X‐ALD and GD.
Living with Hereditary Non‐polyposis Colorectal Cancer; Experiences from and Impact of Genetic Testing
Authors: Carlsson C. , Nilbert M.
Published: August 2007

Hereditary non‐polyposis colorectal cancer (HNPCC) is one of our most common cancer syndromes and an increasing number of individuals live in families with verified hereditary cancer. We conducted an interview study to explore experiences from and perceived impact on life after genetic testing for HNPCC. Three major themes emerged: reactions and emotions, family relations and implications for life. Among the reactions described were suspecting heredity, feelings of guilt, the importance of experiential knowledge, and coping strategies. The impact on family relations was related to perceived responsibility for conveying information, encountering different reactions among family members, and difficulties in communication and relations. The implications described included uncertainty, adaptation, new choices and changes in life, family planning issues, and experiences of surveillance programs. We suggest that the themes and sub‐themes identified should be taken into account during genetic counselling in order to facilitate the spread of information and to prepare family members for the impact on life that knowledge about hereditary cancer may have.
High population density promotes the evolution of ownership
Authors: Horiuchi Shiro
Published: August 2007

Previous studies have discussed the evolution of ownership using the Hawk–Dove–Bourgeois game. Decisive parameters are resource values (V) and contest costs (C). However, ownership may also evolve as a result of the effects of population density. To compare the effects of population density with those of resource values, I created a learning‐based model of a revised Hawk–Dove–Bourgeois game. The game simulates the dynamics of agents that struggle for regions (“territories”) along a line. With appropriate sets of r (resource value) and l (reciprocal of the population density), the model showed that ownership is more likely to evolve when the resource value is small and population density is high. An area containing high‐value resources is likely to accompany high population density. However, simulations showed that population density has stronger effects than resource value on the evolution of ownership.
Effects of Dehydroepiandrosterone (DHEA) on Hepatic Lipid Metabolism Parameters and Lipogenic Gene mRNA Expression in Broiler Chickens
Authors: Tang Xue , Ma Haitian , Zou Sixiang , Chen Weihua
Published: August 2007

The aim of the present study was to identify the effects of dehydroepiandrosterone (DHEA) on hepatic lipid metabolism parameters and lipogenic gene mRNA expression in broiler chickens. A total of 72 1‐day‐old broiler chicks received a common basal diet with DHEA added at either 0 (control), 5 or 20 mg/kg feed. In the present study, the hepatic triglyceride (TG) concentration was significantly lower in male and female broilers that had bed administered DHEA than in control birds. In contrast, DHEA administration caused a marked rise in the hepatic non‐esterified fatty acid (NEFA) concentration in both male and female broilers and also increased lipase (HL) activity in male broilers, while in female birds, no significant differences were observed in HL activity. The expression of peroxisome proliferators‐activated receptor α (PPARα) and carnitine palmitoyl transferase I (CPTI) mRNA was decidedly enhanced following treatment with DHEA, and a similar tendency was also observed in the expression of acyl‐Coenzyme A oxidase 1 (ACOX1). However, no significant differences were observed in the expression of either sterol regulatory element binding protein‐1c (SREBP‐1c) or acetyl CoA carboxylase (ACC) mRNA, except for a decline in the expression of ACC in females treated with 5 mg DHEA/kg. Numerous peroxisomes without a core and an increased number of peroxisomes were evident during morphological observations of broiler livers, in animals that had been treated with DHEA. Overall, the results of the present study indicated that DHEA accelerated lipid catabolism by direct regulation of hepatic lipid metabolism and by induction of relevant gene expression.
Evidence of a two-fold glacial advance during the last glacial maximum in the Tagliamento end moraine system (eastern Alps)
Authors: Monegato Giovanni , Ravazzi Cesare , Donegana Marta , Pini Roberta , Calderoni Gilberto , Wick Lucia
Published: August 2007

The glacial history of the Tagliamento morainic amphitheater (southeastern Alpine foreland, Italy) during the last glacial maximum (LGM) has been reconstructed by means of a geological survey and drillings, radiocarbon dating and pollen analysis in the amphitheater and in the sandur. Two phases of glacial culmination, separated by a distinct recession, are responsible for glacial landforms and related sediments in the outer part of the amphitheater. The age of the younger advance fits the chronology of the culmination of the last glaciation in the Alps, well established between 24 and 21 cal ka BP (20 to 17.514C ka BP), whereas the first pulse between 26.5 and 23 cal ka BP (22 to 2114C ka BP), previously undated, was usually related to older (pre-LGM) glaciations by previous authors. Here, the first pulse is the most extensive LGM culmination, but is often buried by the subsequent pulse. The onset and final recession of the late Würm Alpine glaciation in the Tagliamento amphitheater are synchronous with the established global glacial maximum between 30 and 19 cal ka BP. The two-fold LGM glacial oscillation is interpreted as a millennial-scale modulation within the late Würm glaciation, caused by oscillations in inputs of southerly atmospheric airflows related to Dansgaard–Oeschger cycles. Phases of enhanced southerly circulation promoted increased rainfall and ice accumulation in the southern Alps.
Consumer understanding of nutrition and health claims: sources of evidence
Authors: Leathwood Peter D. , Richardson David P. , Sträter Peter , Todd Peter M. , van Trijp Hans C. M.
Published: August 2007

Provided that they are scientifically substantiated, nutrition and health (NH) claims linked to food products can help consumers make well-informed food choices. The new European legislation on NH claims made on foods entered into force on 19 January 2007. The law sets out conditions for their use, establishes a system for their scientific evaluation, and will create European lists of authorised claims. An important aspect of this proposed legislation is that it states, in article 5.2, ‘the use of nutrition and health claims shall only be permitted if the average consumer can be expected to understand the beneficial effects expressed in the claim’. The present review examines consumer understanding of NH claims from a consumer science perspective. It focuses on the type of data and information that could be needed to provide evidence that the average consumer adequately understands a particular NH claim. After exploring several different methodologies, it proposes a case-specific approach using a stepwise procedure for assessing consumer understanding of a NH claim.
The Trịnh Công Sơn Phenomenon
Authors: Schafer John C.
Published: August 2007

This article attempts to explain the extraordinary popularity of Vietnamese composer and singer Trịnh Công Sơn. Although he attracted attention with love songs composed in the late 1950s, it was his antiwar songs, particularly those collected in Songs of Golden Skin (1966), that created the “Trịnh Công Sơn phenomenon.” Though these songs were banned by the Saigon government, they circulated widely in the South during the war. Though he was distrusted by the new Communist government after the war, Sơn continued to compose until his death in 2001, and his songs are still popular in Vietnam today. Some reasons for his popularity are offered, including the freshness of his early love songs, his evocation of Buddhist themes, his ability to express the mood of Southerners during the war, and a mixture of patience and persistence that enabled him to continue to compose in postwar Vietnam.
Curious Modernities: Early Twentieth-Century Balinese Textual Explorations
Authors: Creese Helen
Published: August 2007

The engagement of Balinese writers and intellectuals with the modern world began well before the final incorporation of the island into the Dutch colonial state in 1906–8. This essay analyzes three Balinese texts, each belonging to a different traditional Balinese literary genre, that were written around the beginning of the twentieth century. These texts, which deal with world events and geography, are Balinese reworkings of material from printed sources into indigenous forms of textual representation. They represent some of the earliest documented shifts toward modernity by indigenous Balinese writers and embody attempts to engage with modernity as a way of both understanding the West and coming to terms with new technologies. As examples of a localized translation of the foreign and the modern, they provide insights into how elite Balinese understandings of modernity were being constituted at the turn of the century.
Cosmic ray detector response to transient solar modulation: Forbush decreases
Authors: Ahluwalia H. S. , Fikani M. M.
Published: August 2007

The observed modulation of galactic cosmic ray (GCR) intensity, on time and spatial scales, contains information regarding their transport in the heliosphere. One way to extract crucial information from the data is to study the rigidity dependence of modulation. A methodology is described to study the rigidity dependence of the short‐term variations in galactic cosmic ray intensity Earth, in terms of the median rigidity of detector response (Rm) to cosmic ray spectrum. We define Rm as the rigidity below which lies 50% of detector counting rate. For neutron monitors (NMs), it is easily calculated from the latitude survey obtained at sea level and higher elevations. We compute Rm values for some NM sites; solar cycle dependence for them is shown to be small. Their practical utility is demonstrated in a study of transient cosmic ray solar modulation (Forbush decreases (FDs)), using data published in the literature. We plot the rigidity dependence of the amplitudes of three large Forbush decreases that occurred during the declining phase of three solar cycles (19, 20, and 21). We show that the Forbush decrease amplitude varies inversely with Rm over a large range (1 to 300 GV) of GCR rigidities. Thereby, we rule out the existence of a “transition rigidity” suggested by Jokipii even for a short‐term modulation (large Forbush decreases). We speculate that the force field model may be applicable to large Forbush decreases.