bluuebunny/crossref_metadata_2025 huggingface dataset:
Enantiomeric separation of chiral pesticides by high performance liquid chromatography on cellulose tris‐3,5‐dimethyl carbamate stationary phase under reversed phase conditions
Authors: Tian Qin , Lv Chunguang , Wang Peng , Ren Liping , Qiu Jing , Li Li , Zhou Zhiqiang
Published: February 2007

Twenty chiral pesticides were tested, of which seven samples were directly separated by HPLC using cellulose tris‐3,5‐dimethyl carbamate (CDMPC) chiral stationary phase under RP conditions. The influence of mobile phase composition and column temperatures from 0°C to 40°C on the separations were investigated. The mobile phases were methanol/water or ACN/water at a flow rate of 0.8 mL/min with UV detection at 230 or 210 nm. Epoxiconazole, terallethrin, benalaxyl, and diclofop‐methyl were observed to obtain the baseline separation under suitable conditions and other pesticides pyriproxyfen, lactofen, and quizalofop‐ethyl were separated partially. The retention factors (k) and selectivity factor (α) for the enantiomers of most investigated pesticides decreased upon increasing the temperature except for the selectivity factors (α) of pyriproxyfen in methanol/water. The ln α–1/T plots for racemic chiral pesticides were linear at the range of 0–40 except for that of pyriproxyfen enantiomers in methanol/water and the chiral separations were controlled by enthalpy. Better separations were not always at low temperature. The elution orders of the eluting enantiomers were determined by a circular dichroism (CD) detector.
Palladium(II) chelate of tetradentate Schiff base as mixed stationary phase for gas chromatography
Authors: Laghari Abdul J. , Khuhawar Muhammad Y. , Ali Zeenat M.
Published: February 2007

Bis(acetylacetone)ethylenediiminepalladium(II) (PdAA2en) was examined as a mixed stationary phase with OV‐1 on Chromosorb G/NAW 60–80 mesh size for the GC separation of aromatic hydrocarbons, heteroaromatics, alcohols, aldehydes, ketones, esters, and nitro compounds. Forty‐two compounds were examined and the GC results were compared with those obtained with 3% OV‐1 on Chromosorb G/NAW 60–80 mesh size under similar operating conditions. Improved resolution, peak asymmetry, theoretical plate numbers, and Kovats indices were obtained on the mixed stationary phase of 3% OV‐1 + 5% PdAA2en compared to 3% OV‐1 column. The stability constant (Km), enthalpies (ΔH), entropies (ΔS), and Gibbs free energies (ΔG) of the GC elution on the column (2 m×3 mm id) packed with 3% OV‐1 + 5% PdAA2en on Chromosorb G/NAW 60–80 mesh size have been calculated. Donor‐acceptor complexation in the gas phase is indicated by negative values of enthalpy (–ΔH) within 5.81 to 10.89 kcal/mol and Gibbs free energy (–ΔG) from 1.34 to 4.08 kcal/mol. The retention time transformations on both the phases were calculated and the ratios obtained from the stationary phases 3% OV‐1 and 3% OV‐1 + 5% PdAA2en were plotted on the x‐axis and the y‐axis, respectively, and the coefficients of determination for alkanes, aromatic and heteroaromatics, ketones, and alcohols were observed to lie within 0.5253 to 0.9742, indicative of some different kinds of interaction of the two stationary phases with the solutes.
Compositional changes induced by UV‐B radiation treatment of common bean and soybean seedlings monitored by capillary electrophoresis with diode array detection
Authors: Dinelli Giovanni , Aloisio Irene , Bonetti Alessandra , Marotti Ilaria , Cifuentes Alejandro
Published: February 2007

In this work, a new CE method with diode array detection (DAD) was developed for the monitoring and quantitation of flavonoids in different beans treated and untreated with UV‐B radiation. Flavonoid concentration was monitored in UV‐B‐treated and untreated sprouts of three common beans (Zolfino ecotype, cv. Verdone, cv. Lingua di Fuoco) and one soybean (cv. Pacific). After acid hydrolysis of extracts, the CE‐DAD method provides reproducible quantitative determinations of daidzein, glycitein, genistein, and kaempferol at ppm level in these natural matrices within a relatively short time (less than 16 min). Total flavonoid content determined by CE‐DAD was 159 ± 8, 26 ± 2, 13 ± 1, and 1.3 ± 0.3 μg/g fresh weight for untreated sprouts of Pacific soybean, Verdone bean, Zolfino bean, and Lingua di Fuoco bean, respectively. UV‐B treatment caused no significant quantitative effect on Pacific soybean sprouts, whereas it enhanced the total isoflavone content by 1.5, 1.8, and 3.2‐fold in Verdone, Zolfino, and Lingua di Fuoco beans, respectively. The proposed method shows (i) the potentialities of bean sprouts as a natural source of bioactive compounds (antioxidants); (ii) the technological role of UV‐B treatment for sprout isoflavone enrichment; and (iii) the good capabilities of CE‐DAD to monitor this process.
Antioxidant compounds of propolis determined by capillary electrophoresis–mass spectrometry
Authors: Gómez‐Romero María , Arráez‐Román David , Moreno‐Torres Rosario , García‐Salas Patricia , Segura‐Carretero Antonio , Fernández‐Gutiérrez Alberto
Published: February 2007

Propolis is a resinous hive product rich in antioxidant compounds. Capillary electrophoresis coupled to mass spectrometric detection can provide selective information about the analytes present in complex extracts of propolis and has turned out to be an attractive alternative to HPLC methods. Therefore, a CE‐ESI‐MS method has been developed for the analysis of antioxidant compounds obtained from propolis. For this purpose, different electrophoretic parameters such as the nature, pH, and concentration of the separation buffer, as well as electrospray parameters (dry gas temperature and flow, nebulising gas pressure, and make‐up flow) have been carefully optimised. Different phenolic compounds (e. g. pinobanksin 3‐acetate, naringenin, pinocembrin, chrysin, daidzein, quercetin 3′,7‐dimethyl ether, apigenin, and kaempferid) could be detected. To confirm the identity of the phenolic compounds in propolis extracts, accurate mass data of the molecular ions were obtained by TOF MS. Limits of detection ranging from 6 mg/100 g of raw propolis for chrysin to 58 mg/100 g of raw propolis for luteolin, were obtained.
Comparison of comprehensive two‐dimensional gas chromatography‐time‐of‐flight mass spectrometry and gas chromatography‐mass spectrometry for the qualitative characterisation of roasted barley by solid‐phase microextraction
Authors: Bianchi Federica , Careri Maria , Conti Chiara , Musci Marilena , Vreuls Renè
Published: February 2007

Volatile compounds of roasted barley used in the production of barley coffee, the most common coffee substitute, were analysed by using solid‐phase microextraction (SPME) followed by GC‐MS and comprehensive GC×GC‐TOF‐MS, respectively. The optimised SPME extraction conditions in terms of selection of the fibre coating, extraction time and extraction temperature allowed to obtain the highest GC response, thus enhancing the identification capabilities of the developed method. As for the SPME‐GC×GC‐TOF‐MS analysis, 64 compounds with similarity, reverse and probability values above 800, 900 and 6000, respectively, were identified, by using a polar×apolar column set combination; in contrast, GC‐MS was able to identify a lower number of compounds, i. e. 40 volatiles.
Template‐Directed Control of Crystal Morphologies
Authors: Meldrum Fiona C. , Ludwigs Sabine
Published: February 2007

Biominerals are characterised by unique morphologies, and it is a long‐term synthetic goal to reproduce these synthetically. We here apply a range of templating routes to investigate whether a fascinating category of biominerals, the single crystals with complex forms, can be produced using simple synthetic methods. Macroporous crystals with sponge‐like morphologies identical to that of sea urchin skeletal plates were produced on templating with a sponge‐like polymer membrane. Similarly, patterning of individual crystal faces was achieved from the micrometer to nanometer scale through crystallisation on colloidal particle monolayers and patterned polymer thin films. These experiments demonstrate the versatility of a templating approach to producing single crystals with unique morphologies.

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Spider Silk and Amyloid Fibrils: A Structural Comparison
Authors: Slotta Ute , Hess Simone , Spieß Kristina , Stromer Thusnelda , Serpell Louise , Scheibel Thomas
Published: February 2007

Although spider silks have been studied for decades, the assembly properties of the underlying silk proteins have still not been unravelled. Previously, the detection of amyloid‐like nanofibrils in the spider's silk gland suggested their involvement in the assembly process.

Recombinantly produced spider silk also self‐assembles into nanofibrils. In order to investigate the structural properties of such silk nanofibrils in more detail, they have been compared to amyloid‐like fibrils to highlight structural similarities.

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Bioinspired Mineralization of Inorganics from Aqueous Media Controlled by Synthetic Polymers
Authors: Gorna Katarzyna , Muñoz‐Espí Rafael , Gröhn Franziska , Wegner Gerhard
Published: February 2007

The formation of inorganic structures in nature is commonly controlled by biogenic macromolecules. The understanding of mineralization phenomena and the nucleation and growth mechanisms involved is still a challenge in science but also of great industrial interest. This article focuses on the formation and mineralization of two archetypical inorganic materials: zinc oxide and amorphous calcium carbonate (ACC). Zinc oxide is selected as a model compound to investigate the role that polymers play in mineralization. Most of the effort has been devoted to the investigation of the effects of double‐hydrophilic block and graft copolymers. Recent work has demonstrated that latex particles synthesized by miniemulsion polymerization, properly functionalized by various chemical groups, have similar effects to conventional block copolymers and are excellently suited for morphology control of ZnO crystals. Latex particles might serve as analogues of natural proteins in biomineralization. The second example presented, ACC, addresses the issue of whether this amorphous phase is an intermediate in the biomineralization of calcite, vaterite, or aragonite. Conditions under which amorphous calcium carbonate can be obtained as nanometer‐sized spheres as a consequence of a liquid–liquid phase segregation are presented. Addition of specific block copolymers allows control of the particle size from the micrometer to the submicrometer length scale. The physical properties of novel materials synthesized from concentrated solution and their potential applications as a filler of polymers are also discussed.

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Potential of Various Archae‐ and Eubacterial Strains as Industrial Polyhydroxyalkanoate Producers from Whey
Authors: Koller Martin , Hesse Paula , Bona Rodolfo , Kutschera Christoph , Atlić Aid , Braunegg Gerhart
Published: February 2007

Three different microbial wild‐type strains are compared with respect to their potential as industrial scale polyhydroxyalkanoate (PHA) producers from the feed stock whey lactose. The halophilic archaeon Haloferax mediterranei as well as two eubacterial strains (Pseudomonas hydrogenovora and Hydrogenophaga pseudoflava) are investigated. H. mediterranei accumulated 50 wt.‐% of poly‐3‐(hydroxybutyrate‐co‐8%‐hydroxyvalerate) from hydrolyzed whey without addition of 3‐hydroxyvalerate (3HV) precursors (specific productivity qp: 9.1 mg · g−1 · h−1). Using P. hydrogenovora, the final percentage of poly‐3‐hydroxybutyrate (PHB) amounted to 12 wt.‐% (qp: 2.9 mg · g−1 · h−1). With H. pseudoflava, it was possible to reach 40 wt.‐% P‐3(HB‐co‐5%‐HV) on non‐hydrolyzed whey lactose plus addition of valeric acid as 3HV precursor (qp: 12.5 mg · g−1 · h−1). A detailed characterization of the isolated biopolyesters and an evaluation with regard to the economic feasibility completes the study.

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Suberin: A Biopolyester of Plants' Skin
Authors: Graça José , Santos Sara
Published: February 2007

Suberin is a biopolymer that acts as a barrier between plants and the environment. It is known to be a complex polyester based on glycerol and long‐chain α,ω‐diacids and ω‐hydroxyacids. How these monomeric units are assembled at a macromolecular level remains mostly unknown. The knowledge gathered in the last 10 years has opened new insights into suberin structure. Suberin oligomeric blocks have been obtained after the partial depolymerization of the biopolymer, and in‐situ studies by solid‐state 13C NMR spectroscopy have shown different molecular domains and how they are spatially related. Based on these latter developments, a model is proposed for the suberin macromolecular structure. The uniqueness of the suberin polyester opens perspectives for its use as a source of bio‐based materials.

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Bio‐Refinery as the Bio‐Inspired Process to Bulk Chemicals
Authors: Sanders Johan , Scott Elinor , Weusthuis Ruud , Mooibroek Hans
Published: February 2007

This paper describes several examples of knowledge‐intensive technologies for the production of chemicals from biomass, which take advantage of the biomass structure in a more efficient way than the production of fuels or electricity alone. The depletion in fossil feedstocks, increasing oil prices, and the ecological problems associated with CO2 emissions are forcing the development of alternative resources for energy, transport fuels, and chemicals, such as the replacement of fossil resources with CO2 neutral biomass. Allied with this is the conversion of crude oil products utilizes primary products (ethylene, etc.) and their conversion into either materials or (functional) chemicals with the aid of co‐reagents such as ammonia, by various process steps to introduce functionalities such as ‐NH2 into the simple structures of the primary products. Conversely, many products found in biomass often contain functionalities. Therefore, it is attractive to exploit this in order to by‐pass the use, and preparation of, co‐reagents as well as to eliminate various process steps by utilizing suitable biomass‐based precursors for the production of chemicals.

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Functional, Hierarchically Structured Poly(diacetylene)s via Supramolecular Self‐Assembly
Authors: Jahnke Eike , Millerioux Anne‐Sophie , Severin Nikolai , Rabe Jürgen P. , Frauenrath Holger
Published: February 2007

The supramolecular self‐assembly of macromonomers may serve as a first step to prepare well‐defined, highly functionalized, hierarchically structured, conjugated polymers. Functional diacetylene macromonomers equipped with an oligopeptide segment designed to promote self‐assembly into parallel β‐sheet type structures and a polydisperse, aliphatic coil segment to prevent global ordering give rise to supramolecular polymers with a tubular double‐helical quarternary structure in organic solution. These supramolecular polymers may then be converted into the corresponding poly(diacetylene)s by UV irradiation under retention of their hierarchical structure.
Inhibition of gastric H+,K+‐ATPase and Helicobacter pylori growth by phenolic antioxidants of Zingiber officinale
Authors: Siddaraju M. N. , Dharmesh Shylaja M.
Published: February 2007

Ulcer is a common global problem characterized by acute gastric irritability, bleeding, etc. due to either increased gastric cell proton potassium ATPase activity (PPA) or perturbation of mucosal defence. Helicobacter pylori has been identified as a major ulcerogen in addition to oxidative stress and nonsteroidal anti‐inflammatory drugs. In this paper, we report ginger‐free phenolic (GRFP) and ginger hydrolysed phenolic (GRHP) fractions of ginger (Zingiber officinale) as potent inhibitors of PPA and H. pylori growth. GRFP and GRHP inhibited PPA at an IC50 of 2.9 ± 0.18 and 1.5 ± 0.12 μg/mL, exhibiting six‐ to eight‐fold better potency over lansoprazole. GRFP is constituted by syringic (38%), gallic (18%) and cinnamic (14%) acids and GRHP by cinnamic (48%), p‐coumaric (34%) and caffeic (6%) acids as major phenolic acids. GRFP and GRHP further exhibited free radical scavenging (IC50 1.7 ± 0.07 and 2.5 ± 0.16), inhibition of lipid peroxidation (IC50 3.6 ± 0.21 and 5.2 ± 0.46), DNA protection (80% at 4 μg) and reducing power abilities (80–338 U/g) indicating strong antioxidative properties. GRFP and GRHP may thus be potential in‐expensive multistep blockers against ulcer.
Flavonoids alter P‐gp expression in intestinal epithelial cellsin vitroandin vivo
Authors: Lohner Katrin , Schnäbele Kerstin , Daniel Hannelore , Oesterle Doris , Rechkemmer Gerhard , Göttlicher Martin , Wenzel Uwe
Published: February 2007

Flavonoids are secondary plant metabolites included in our diet but are also provided in a growing number of supplements. They are suggested to interact with intestinal transport systems including phospho‐glycoprotein (P‐gp) which mediates the efflux of a variety of xenobiotics back into the gut lumen. In human intestinal Caco‐2 cells, we tested the effects of 14 different flavonoids on P‐gp expressionin vitro. Protein expression levels were quantified by Western blotting, flow cytometry, and real‐time PCR. Except apigenin, all flavonoids at concentrations of 10 μM increased P‐gp expression in Western blotting experiments when cells were exposed to the compounds over 4 wk. Flavone was one of the most effective P‐gp inducers in Caco‐2 cells and its effects were, therefore, also assessed for changes in P‐gpin vivoin the gastrointestinal tract of C57BL/6 mice. P‐gp expression was significantly increased by flavone (400 mg/kg body weight×day over 4 wk) in the small intestine but not in the colon which displayed intrinsically the highest expression level. In conclusion, the increase in P‐gp expression caused by flavonoids in intestinal epithelial cellsin vitroand alsoin vivomay serve as an adaptation and defense mechanism limiting the entry of lipophilic xenobiotics into the organism.
Selective excitation of overlapping multiplets; the application of doubly selective and chemical shift filter experiments to complex NMR spectra
Authors: Duncan Sara J. , Lewis Richard , Bernstein Michael A. , Sandor Peter
Published: February 2007

Standard 1D TOCSY and NOE experiments have limitations where signals are severely overlapped. Here, two recently published selective excitation methods are evaluated, the first of which uses a chemical shift selective filter to select a single resonance based on its chemical shift, and the second of which is a doubly selective experiment comprising a 1D TOCSY preparation step and subsequent 1D NOE. We also demonstrate the improvement in spectral quality obtained by the use of the zero quantum filter, which is incorporated into both of these experiments. The application of these different methods of selectively exciting overlapped multiplets, to different types of samples is considered. Copyright © 2007 John Wiley & Sons, Ltd.
Frequent atrophic groups with mixed‐type myofibers is distinctive to motor neuron syndromes
Authors: Baloh Robert H. , Rakowicz Wojtek , Gardner Robert , Pestronk Alan
Published: February 2007

This study was performed to determine whether there are distinctive features to the pattern of muscle denervation in motor neuron disease. We first compared muscle biopsies from patients with amyotrophic lateral sclerosis (ALS) or Kennedy's disease with other causes of denervation. Groups of atrophic muscle fibers, with individual groups containing both fiber types I and II, occurred frequently in motor neuron disease but not other causes of denervation. We then identified 11 additional muscle biopsies with frequent atrophic groups containing mixed fiber types. Chart review revealed that 10 patients had a final diagnosis of motor neuron disease or ALS and one had multifocal motor neuropathy. We conclude that muscle biopsy may have diagnostic utility early in the course of motor neuron disease. The muscle biopsy pattern of frequent atrophic groups containing mixed fiber types should suggest a diagnosis of a motor neuron syndrome or motor neuropathy. Muscle Nerve, 2007
Neuromuscular electrical stimulation in neurorehabilitation
Authors: Sheffler Lynne R. , Chae John
Published: February 2007

This review provides a comprehensive overview of the clinical uses of neuromuscular electrical stimulation (NMES) for functional and therapeutic applications in subjects with spinal cord injury or stroke. Functional applications refer to the use of NMES to activate paralyzed muscles in precise sequence and magnitude to directly accomplish functional tasks. In therapeutic applications, NMES may lead to a specific effect that enhances function, but does not directly provide function. The specific neuroprosthetic or “functional” applications reviewed in this article include upper‐ and lower‐limb motor movement for self‐care tasks and mobility, respectively, bladder function, and respiratory control. Specific therapeutic applications include motor relearning, reduction of hemiplegic shoulder pain, muscle strengthening, prevention of muscle atrophy, prophylaxis of deep venous thrombosis, improvement of tissue oxygenation and peripheral hemodynamic functioning, and cardiopulmonary conditioning. Perspectives on future developments and clinical applications of NMES are presented. Muscle Nerve, 2007
Dynamic contrast‐enhanced MRI of muscle perfusion combined with MR angiography of collateral artery growth in a femoral artery ligation model
Authors: de Lussanet Quido G. , van Golde Jolanda C. G. , Beets‐Tan Regina G. H. , Post Mark J. , Huijberts Maya S. , Schaper Nicolaas C. , Kessels Alphons G. H. , van Engelshoven Jos M. A. , Backes Walter H.
Published: February 2007

To assess the use of MRI for evaluating changes in muscle blood flow and number of collateral arteries, serial dynamic contrast‐enhanced MRI (DCE‐MRI) was combined with high‐spatial‐resolution contrast‐enhanced MR angiography (MRA) in a peripheral ischemia model.The combined MRI (DCE‐MRI and MRA) protocol was performed serially in 15 male rabbits at 2 h (day 0+), 7 days, and 21 days after femoral artery ligation. In the anterior tibial and soleus muscle, changes in resting muscle blood flow determined as the endothelial transfer coefficient (Ktrans) and arterial inflow delay from DCE‐MRI and changes in the number of sub‐millimeter sized collateral arteries as scored with MRA were measured. Directly after ligation, Ktrans in the anterior tibial muscle was reduced to 23% of that in the control limb, then recovered to 81% on day 7, and to 85 % on day 21. Ktrans in the soleus muscle recovered from a reduction to 63% on day 0+, to 85% on day 7, and to 90% on day 21. The number of collaterals around the ligated femoral artery increased from 1.1 on day 0+ to 4.2 on day 7, and 6.0 on day 21 in the ligated limb only. Combined DCE‐MRI and MRA allows non‐invasive serial monitoring of changes in muscle blood flow and growth of sub‐millimeter sized collateral arteries in a rabbit femoral artery ligation model. Copyright © 2007 John Wiley & Sons, Ltd.
Reduced integration post‐processing techniques for Darcy's velocity recovery in bilinear quadrilaterals
Authors: Dias C. M. , Malta S. M. C. , Coutinho A. L. G. A. , Loula A. F. D.
Published: February 2007

In this work we propose the use of a reduced integration technique for bilinear quadrilateral elements in the determination of the Darcy's velocity via global and local post‐processing techniques. This approach increases accuracy in distorted meshes and leads to a reduction in the computational effort for matrix coefficients and residuals evaluations. Numerical examples are shown to validate our approach, accessing its efficiency and accuracy. Copyright © 2007 John Wiley & Sons, Ltd.
A new formulation and 𝒞0‐implementation of dynamically consistent gradient elasticity
Authors: Askes Harm , Bennett Terry , Aifantis Elias C.
Published: February 2007

In his article a special form of gradient elasticity is presented that can be used to describe wave dispersion. This new format of gradient elasticity is an appropriate dynamic extension of the earlier static counterpart of the gradient elasticity theory advocated in the early 1990s by Aifantis and co‐workers. In order to capture dispersion of propagating waves, both higher‐order inertia and higher‐order stiffness contributions are included, a fact which implies (and is denoted as) dynamic consistency. The two higher‐order terms are accompanied by two associated length scales. To facilitate finite element implementations, the model is rewritten such that 𝒞0‐continuity of the interpolation is sufficient. An auxiliary displacement field is introduced which allows the original fourth‐order equations to be split into two coupled sets of second‐order equations. Positive‐definiteness of the kinetic energy requires that the inertia length scale is larger than the stiffness length scale. The governing equations, boundary conditions and the discretized system of equations are presented. Finally, dispersive wave propagation in a one‐dimensional bar is considered in a numerical example. Copyright © 2007 John Wiley & Sons, Ltd.
Insulin receptor activation in solitary fibrous tumours
Authors: Li Y , Chang Q , Rubin BP , Fletcher CDM , Morgan TW , Mentzer SJ , Sugarbaker DJ , Fletcher JA , Xiao S
Published: February 2007

Solitary fibrous tumours (SFTs) are known to overexpress insulin‐like growth factor 2 (IGF‐2). The down‐stream oncogenic pathways of IGF‐2, however, are not clear. Here we report uniform activation of the insulin receptor (IR) pathway in SFTs, which are mesenchymal tumours frequently associated with hypoglycaemia. Whereas the IR and its downstream signalling pathways were constitutively activated in SFTs, insulin‐like growth factor 1 receptor (IGF‐1R) was not expressed in these tumours. We also find that SFT cells secrete IGF‐2 and proliferate in serum‐free medium, consistent with an IGF‐2/IR autocrine loop. The aetiological relevance of IGF‐2 is supported by expression of IR‐A, the IR isoform with high affinity for IGF‐2, in all SFTs. Our studies suggest that IR activation plays an oncogenic role in SFTs. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Slug is overexpressed in gastric carcinomas and may act synergistically with SIP1 and Snail in the down‐regulation of E‐cadherin
Authors: Alves C Castro , Rosivatz E , Schott C , Hollweck R , Becker I , Sarbia M , Carneiro F , Becker K‐F
Published: February 2007

Epithelial–mesenchymal transition (EMT) involving down‐regulation of E‐cadherin is known to play an important role in tumour progression. The aim of our study was to investigate the mRNA expression of two EMT regulators—Slug and E12/E47—in primary human gastric carcinomas and to compare this with the expression of E‐cadherin and other EMT regulators (Snail, Twist, and SIP1). We studied a series of 59 gastric carcinomas by real‐time quantitative RT‐PCR in formalin‐fixed and paraffin‐embedded tissues. Thirty‐four cases (58%) showed Slug up‐regulation in the tumour; reduced or negative expression of E‐cadherin was present in 24 of these (71%, p < 0.0001). Twenty‐one cases (36%) showed E12/E47 up‐regulation that was not significantly associated with E‐cadherin down‐regulation (p = 0.5734). Slug up‐regulation accompanied by E‐cadherin down‐regulation correlated with the presence of distant metastases (p = 0.0029) and with advanced pTNM stages (p = 0.0424). A statistically significant association was found between Slug up‐regulation and the expression of SIP1 in intestinal (p = 0.0014) and Snail in diffuse (p = 0.0067) carcinomas. We present the first study integrating the analysis of several EMT regulators in primary gastric carcinomas and conclude that Slug up‐regulation is associated with E‐cadherin down‐regulation in diffuse and intestinal‐type gastric carcinoma, and that this effect could be complemented by the presence of other EMT regulators. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Midtrimester maternal serum inhibin A levels after multifetal pregnancy reduction
Authors: Chen Heng‐Ju , Huang Lee‐Wen , Lin Yu‐Hung , Seow Kok‐Min , Hsieh Bih‐Chwen , Hwang Jiann‐Loung , Tzeng Chii‐Ruey
Published: February 2007

Objective

To investigate the relationship between the maternal serum inhibin A concentrations and the number of fetuses. Further, the maternal serum inhibin A levels for twin pregnancies and multiple pregnancies reduced to twins in the second trimester were compared.

Methods

Three groups of women with pregnancies following in vitro fertilization and embryo transfer were recruited for this study. Groups 1, 2 and 3 included 20 singleton pregnancies, 37 twin pregnancies, and 35 multifetal pregnancies, respectively. In group 3, multifetal reduction was performed during 10–12 weeks of gestation. Blood samples were obtained longitudinally at 10th, 12th, 15th and 18th week of gestation.

Results

There was a significant association between the number of fetuses and maternal plasma inhibin A prior to multifetal reduction. The inhibin A levels were not significantly different between twin and multifetal reduced twin pregnancies at 15th and 18th weeks of gestation.

Conclusion

In multifetal reduction to twin pregnancies, the maternal serum levels of inhibin A decrease to the level of twin pregnancies during the second trimester. Therefore, inhibin A may be effectively used as a marker for Down syndrome screening in cases of twin pregnancy following multifetal reduction. Copyright © 2007 John Wiley & Sons, Ltd.
Personality constructs and measures
Authors: Teglasi Hedwig , Simcox April G. , Kim Na‐Young
Published: February 2007

A psychological construct, such as personality, is an abstraction that is not directly seen but inferred through observed regularities in cognitive, affective, and behavioral responses in various settings. Two assumptions give meaning to the idea of construct validity. First, constructs represent real phenomena that exist apart from the potential ways in which they are measured. Second, constructs have a causal relation to their measures (see D. Boorsboom, G.J. Mellenbergh, & J. van Heerden, 2004). According to these twin assumptions, variation in a construct such as personality or intelligence causes individual differences in responses to items on measures; it also accounts for performance in real life settings. An alternative perspective equates a construct with the operation used for its measurement (M. Friedman, 1991) without a presumption of causality. This article elaborates on the implications of different assumptions about measurement, operation‐referenced and construct‐referenced, for advancing the science and practice of psychology. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 215–228, 2007.
Figure drawings: A popular method
Authors: Flanagan Rosemary , Motta Robert W.
Published: February 2007

Research, commentary, and interpretive procedures reflecting varied perspectives on figure drawings are presented in order to suggest contemporary practice models for school psychologists. The review of the extensive literature includes measures with scoring systems that are normed and those systems that rely on clinical traditions for interpretation. Available scoring systems demonstrate adequate reliability and validity for screening purposes, but evidence of their utility for diagnosis of an individual by interpretation of drawings is nonexistent. Drawing data can be useful when they are aggregated with other data and interpreted in a configural manner to obtain a description of the individual, or when the focus of assessment is on overarching constructs such as well‐being. Finally, figure drawings may aid in establishing rapport with youth and provide a springboard for practitioner hypotheses, guiding the course of the assessment. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 257–270, 2007.
Narrative methods of personality assessment in school psychology
Authors: Esquivel Giselle B. , Flanagan Rosemary
Published: February 2007

This critical review of narrative methods of personality assessment highlights their value in understanding unique aspects of personality functioning of children and adolescents in the context of school psychology. The use of narratives for assessment is based on constructivist theories emphasizing the role of the person and the social group in assigning meaning to reality through the use of storytelling processes. Narrative analysis is linked to thematic apperception techniques within a personological paradigm of assessment that attends to the internal and interpersonal processes underlying personality development. A comprehensive framework is described to guide the use of narrative methods of assessing children and adolescents. Research is proposed to validate these methods further as an integral aspect of personality assessment in school psychology. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 271–280, 2007.
Comments on the miniseries: Personality assessment in school psychology
Authors: Flanagan Rosemary
Published: February 2007

Although personality assessment in school psychology is important, attention appropriate to its importance is not the norm. The miniseries contributions addressing ways personality is defined, considerations assessing diverse populations, data integration, projective or performance assessment, and Therapeutic Assessment are reviewed. Although prepared for school psychologists, the information should be helpful for all child practitioners. Important recommendations for school psychological practice are (1) the role of school psychologist should be expanded to evaluate personality beyond the level of screening, (2) personality assessment should include more than questionnaire data, (3) data obtained from varied measures should be integrated to provide a description as well as a diagnosis of the youngster, and (4) use of theory to guide interpretation is desirable. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 311–318, 2007.
Developmental vitamin D deficiency alters brain protein expression in the adult rat: Implications for neuropsychiatric disorders
Authors: Almeras Lionel , Eyles Darryl , Benech Philippe , Laffite Daniel , Villard Claude , Patatian Angela , Boucraut Jose , Mackay‐Sim Alan , McGrath John , Féron François
Published: February 2007

An increased risk for multiple sclerosis and schizophrenia is observed at increasing latitude and in patients born in winter or spring. To explore a possible link between maternal vitamin D deficiency and these brain disorders, we examined the impact of prenatal hypovitaminosis D on protein expression in the adult rat brain. Vitamin D‐deficient female rats were mated with vitamin D normal males. Pregnant females were kept vitamin D‐deficient until birth whereupon they were returned to a control diet. At week 10, protein expression in the progeny's prefrontal cortex and hippocampus was compared with control animals using silver staining 2‐D gels associated with MS and newly devised data mining software. Developmental vitamin D (DVD) deficiency caused a dysregulation of 36 brain proteins involved in several biological pathways including oxidative phosphorylation, redox balance, cytoskeleton maintenance, calcium homeostasis, chaperoning, PTMs, synaptic plasticity and neurotransmission. A computational analysis of these data revealed that (i) nearly half of the molecules dysregulated in our animal model have also been shown to be misexpressed in either schizophrenia and/or multiple sclerosis and (ii) an impaired synaptic network may be a consequence of mitochondrial dysfunction.
SELDI‐TOF‐MS analysis of chloroquine resistant and sensitive Plasmodium falciparum strains
Authors: Koncarevic Sasa , Bogumil Ralf , Becker Katja
Published: February 2007

The resistance of the malarial parasite Plasmodium falciparum to chloroquine represents an emerging problem since neither mode of drug action nor mechanisms of resistance are fully elucidated. We describe a protein expression profiling approach by SELDI‐TOF‐MS as a useful tool for studying the proteome of malarial parasites. Reproducible and complex protein profiles of the P. falciparum strains K1, Dd2, HB3 and 3D7 were measured on four array types. Hierarchical clustering led to a clear separation of the two major subgroups “resistant” and “sensitive” as well as of the four parasite strains. Our study delivers sets of regulated proteins derived from extensive comparative analyses of 64 P. falciparum protein profiles. A group of 12 peaks reflecting proteome changes under chloroquine treatment and a set of 10 potential chloroquine resistance markers were defined. Three of these regulated peaks were preparatively enriched, purified and identified. They were shown to represent the plasmodial EXP‐1 protein, also called circumsporozoite‐related antigen, as well as the α‐ and β‐ (δ‐) chains of human hemoglobin.
Proteomic analysis of spinal protein expression in rats exposed to repeated intrathecal morphine injection
Authors: Shui Hao‐Ai , Ho Shung‐Tai , Wang Jhi‐Joung , Wu Chin‐Chen , Lin Chih‐Huan , Tao Yuan‐Xiang , Liaw Wen‐Jinn
Published: February 2007

Repeated administration of morphine for treating severe chronic pain may lead to neuroadaptive changes in the spinal cord that are thought to underlie molecular mechanisms of the development of morphine tolerance and physical dependence. Here, we employed a 2‐D gel‐based proteomic technique to detect the global changes of the spinal cord protein expression in rats that had developed morphine tolerance. Morphine tolerance at the spinal cord level was induced by repeated intrathecal injections of morphine (20 μg/10 μL) twice daily for 5 days and evaluated by measurements of paw withdrawal latencies and maximal possible analgesic effect at day 5. After behavioral tests, the lumbar enlargement segments of spinal cord were harvested and proteins resolved by 2‐DE. We found that eight proteins were significantly up‐regulated or down‐regulated in spinal cord after morphine tolerance development, including proteins involved in targeting and trafficking of the glutamate receptors and opioid receptors, proteins involved in oxidative stress, and cytoskeletal proteins, some of which were confirmed by Western blot analysis. Morphine‐induced expressional changes of these proteins in the spinal cord might be involved in the central mechanisms that underlie the development of morphine tolerance. It is very likely that these identified proteins may serve as potential molecular targets for prevention of the development of morphine tolerance and physical dependence.
Proteomic approach for identification and characterization of novel immunostimulatory proteins from soluble antigens of Leishmania donovani promastigotes
Authors: Gupta Shraddha Kumari , Sisodia Brijesh Singh , Sinha Sudhir , Hajela Krishnan , Naik Sita , Shasany Ajit Kumar , Dube Anuradha
Published: February 2007

Visceral leishmaniasis (VL) caused by Leishmania donovani is a major parasitic disease prevalent in endemic regions of Bihar in India. In the absence of good chemotherapeutic options, there is a need to develop an effective vaccine against VL which should be dependent on the generation of a T helper type 1 (Th1) immune response. We have shown that soluble proteins from promastigote of a new clinical isolate of L. donovani (2001) ranging from 68 to 97.4 kDa (F2 fraction), induce Th1 responses in the peripheral blood mononuclear cells of cured Leishmania patients and hamsters and also showed significant prophylactic potential. To understand the nature of F2 proteins, it was further characterized using 2‐DE, MALDI‐TOF and MALDI‐TOF/TOF‐MS. In all, 63 spots were cut from a CBB stained gel for analysis and data was retrieved for 52 spots. A total of 33 proteins were identified including six hypothetical/unknown proteins. Major immunostimulatory proteins were identified as elongation factor‐2, p45, heat shock protein (HSP)70, HSP83, aldolase, enolase, triosephosphate isomerase, protein disulfideisomerase and calreticulin. This study substantiates the usefulness of proteomics in characterizing a complex protein fraction (F2) map of soluble L. donovani promastigote antigen identified as Th1 stimulatory for its potential as vaccine targets against VL.
Minimum model for the α‐helix–β‐hairpin transition in proteins
Authors: Imamura Hideo , Chen Jeff Z. Y.
Published: February 2007

We present a minimal model for proteins, which is able to capture the structural conversion between the α‐helix and β‐hairpin. In most regimes of the parameter space, the model produces a stable structure at a low temperature; in a few limited regimes of the parameter space, the model displays an β‐hairpin transition as the physical conditions vary. These variations include a perturbation on hydrogen bonding propensity at the middle of the modeled chain, or the change of the hydrophobicity of a designated pair along the chain. Using Monte Carlo simulations, we demonstrate the structural conversion by means of state diagrams, heat capacity maps, and free energy maps. Proteins 2007. © 2007 Wiley‐Liss, Inc.
PIER: Protein interface recognition for structural proteomics
Authors: Kufareva Irina , Budagyan Levon , Raush Eugene , Totrov Maxim , Abagyan Ruben
Published: February 2007

Recent advances in structural proteomics call for development of fast and reliable automatic methods for prediction of functional surfaces of proteins with known three‐dimensional structure, including binding sites for known and unknown protein partners as well as oligomerization interfaces. Despite significant progress the problem is still far from being solved. Most existing methods rely, at least partially, on evolutionary information from multiple sequence alignments projected on protein surface. The common drawback of such methods is their limited applicability to the proteins with a sparse set of sequential homologs, as well as inability to detect interfaces in evolutionary variable regions. In this study, the authors developed an improved method for predicting interfaces from a single protein structure, which is based on local statistical properties of the protein surface derived at the level of atomic groups. The proposed Protein IntErface Recognition (PIER) method achieved the overall precision of 60% at the recall threshold of 50% at the residue level on a diverse benchmark of 490 homodimeric, 62 heterodimeric, and 196 transient interfaces (compared with 25% precision at 50% recall expected from random residue function assignment). For 70% of proteins in the benchmark, the binding patch residues were successfully detected with precision exceeding 50% at 50% recall. The calculation only took seconds for an average 300‐residue protein. The authors demonstrated that adding the evolutionary conservation signal only marginally influenced the overall prediction performance on the benchmark; moreover, for certain classes of proteins, using this signal actually resulted in a deteriorated prediction. Thorough benchmarking using other datasets from literature showed that PIER yielded improved performance as compared with several alignment‐free or alignment‐dependent predictions. The accuracy, efficiency, and dependence on structure alone make PIER a suitable tool for automated high‐throughput annotation of protein structures emerging from structural proteomics projects. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Essential dynamics sampling study of adenylate kinase: Comparison to citrate synthase and implication for the hinge and shear mechanisms of domain motions
Authors: Snow Catherine , Qi Guoying , Hayward Steven
Published: February 2007

Essential dynamics sampling simulations of the domain conformations of unliganded Escherichia coli adenylate kinase have been performed to determine whether the ligand‐induced closed‐domain conformation is accessible to the open unliganded enzyme. Adenylate kinase is a three‐ domain protein with a central CORE domain and twoflanking domains, the LID and the NMPbind domains. The sampling simulations were applied to the CORE and NMPbind domain pair and the CORE and LID domain pair separately. One aim is to compare the results to those of a similar study on the enzyme citrate synthase to determine whether a similar domain‐locking mechanism operates in adenylate kinase. Although for adenylate kinase the simulations suggest that the closed‐domain conformation of the unliganded enzyme is at a slightly higher free energy than the open for both domain pairs, the results are radically different to those found for citrate synthase. In adenylate kinase the targeted domain conformations could always be achieved, whereas this was not the case in citrate synthase due to an apparent free‐energy barrier between the open and closed conformations. Adenylate kinase has been classified as a protein that undergoes closure through a hinge mechanism, whereas citrate synthase has been assigned to the shear mechanism. This was quantified here in terms of the change in the number of interdomain contacting atoms upon closure which showed a considerable increase in adenylate kinase. For citrate synthase this number remained largely the same, suggesting that the domain faces slide over each other during closure. This suggests that shear and hinge mechanisms of domain closure may relate to the existence or absence of an appreciable barrier to closure for the unliganded protein, as the latter can hinge comparatively freely, whereas the former must follow a more constrained path. In general though it appears a bias toward keeping the unliganded enzyme in the open‐domain conformation may be a common feature of domain enzymes. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Periodic distributions of hydrophobic amino acids allows the definition of fundamental building blocks to align distantly related proteins
Authors: Baussand J. , Deremble C. , Carbone A.
Published: February 2007

Several studies on large and small families of proteins proved in a general manner that hydrophobic amino acids are globally conserved even if they are subjected to high rate substitution. Statistical analysis of amino acids evolution within blocks of hydrophobic amino acids detected in sequences suggests their usage as a basic structural pattern to align pairs of proteins of less than 25% sequence identity, with no need of knowing their 3D structure. The authors present a new global alignment method and an automatic tool for Proteins with HYdrophobic Blocks ALignment (PHYBAL) based on the combinatorics of overlapping hydrophobic blocks. Two substitution matrices modeling a different selective pressure inside and outside hydrophobic blocks are constructed, the Inside Hydrophobic Blocks Matrix and the Outside Hydrophobic Blocks Matrix, and a 4D space of gap values is explored. PHYBAL performance is evaluated against Needleman and Wunsch algorithm run with Blosum 30, Blosum 45, Blosum 62, Gonnet, HSDM, PAM250, Johnson and Remote Homo matrices. PHYBAL behavior is analyzed on eight randomly selected pairs of proteins of >30% sequence identity that cover a large spectrum of structural properties. It is also validated on two large datasets, the 127 pairs of the Domingues dataset with >30% sequence identity, and 181 pairs issued from BAliBASE 2.0 and ranked by percentage of identity from 7 to 25%. Results confirm the importance of considering substitution matrices modeling hydrophobic contexts and a 4D space of gap values in aligning distantly related proteins. Two new notions of local and global stability are defined to assess the robustness of an alignment algorithm and the accuracy of PHYBAL. A new notion, the SAD‐coefficient, to assess the difficulty of structural alignment is also introduced. PHYBAL has been compared with Hydrophobic Cluster Analysis and HMMSUM methods. Proteins 2007. © 2007 Wiley‐Liss, Inc.