bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of ligand binding on human D‐amino acid oxidase: Implications for the development of new drugs for schizophrenia treatment
Authors: Caldinelli Laura , Molla Gianluca , Bracci Luisa , Lelli Barbara , Pileri Silvia , Cappelletti Pamela , Sacchi Silvia , Pollegioni Loredano
Published: June 2010

In human brain the flavoprotein D‐amino acid oxidase (hDAAO) is responsible for the degradation of the neuromodulator D‐serine, an important effector of NMDA‐receptor mediated neurotransmission. Experimental evidence supports the concept that D‐serine concentration increase by hDAAO inhibition may represent a valuable therapeutic approach to improve the symptoms in schizophrenia patients. This study investigated the effects on hDAAO conformation and stability of the substrate D‐serine (or of the pseudo‐substrate trifluoro‐D‐alanine), the FAD cofactor, and two inhibitors (benzoate, a classical substrate‐competitive inhibitor and the drug chlorpromazine (CPZ), which competes with the cofactor). We demonstrated that all these compounds do not alter the interaction of hDAAO with its physiological partner pLG72. The ligands used affect the tertiary structure of hDAAO differently: benzoate or trifluoro‐D‐alanine binding increases the amount of the holoenzyme form in solution and stabilizes the flavoprotein, while CPZ binding favors a protein conformation resembling that of the apoprotein, which is more sensitive to degradation. Interestingly, the apoprotein form of hDAAO binds the substrate D‐serine: this interaction increases FAD binding thus increasing the amount of active holoenzyme in solution. Benzoate and CPZ similarly modify the short‐term cellular D‐serine concentration but affect the cellular concentration of hDAAO differently. In conclusion, the different alteration of hDAAO conformation and stability by the ligands used represents a further parameter to take into consideration during the development of new drugs to cope schizophrenia.
Future colliders at CERN
Authors: Tsesmelis E.
Published: June 2010

Following an outline of the Large Hadron Collider, this paper will analyze CERN's scientific plans for high‐energy colliders for the years to come. The immediate plans include the upgrades to the Large Hadron Collider and its injectors. This may be followed by a linear electron‐positron collider, the Compact Linear Collider. This paper describes the design of these future colliders at CERN, all of which have a unique value to add to experimental particle physics
Constitutive expression of bioactivating enzymes in normal human prostate suggests a capability to activate pro‐carcinogens to DNA‐damaging metabolites
Authors: Martin Francis L. , Patel Imran I. , Sozeri Osman , Singh Paras B. , Ragavan Narasimhan , Nicholson Caroline M. , Frei Eva , Meinl Walter , Glatt Hansruedi , Phillips David H. , Arlt Volker M.
Published: June 2010

BACKGROUND

The constitutive bioactivating capacity of human prostate may play a role in determining risk of adenocarcinoma developing in this tissue. Expression of candidate enzymes that convert exogenous and/or endogenous agents into reactive DNA‐damaging species would suggest the potential to generate initiating events in prostate cancer (CaP).

METHODS

Normal prostate tissues from UK‐resident Caucasians (n = 10) were collected following either radical retropubic prostatectomy (RRP) or cystaprostatectomy (CyP). An analysis of gene and protein expression of candidate metabolizing enzymes, including cytochrome P450 (CYP)1A1, CYP1A2, CYP1B1, N‐acetyltransferase 1 (NAT1), sulfotransferase (SULT)1A1, SULT1A3, NAD(P)H:quinone oxidoreductase (NQO1), prostaglandin H synthase 1 (cyclooxygenase 1; COX1), and CYP oxidoreductase (POR) was carried out. Quantitative real‐time reverse transcriptase polymerase chain reaction, Western blot, and immunohistochemical analysis were conducted.

RESULTS

Except for CYP1A1 and CYP1A2, the metabolizing enzymes examined appeared to be expressed with minimal inter‐individual variation (in general, approximately two‐ to fivefold) in the expression levels. Enzymes such as CYP1B1 and NQO1 that are capable of bioactivating pro‐carcinogens to reactive metabolites were readily identifiable in human prostate. Immunohistochemical analysis showed that although some expression is located in the stroma, the majority is localized to epithelial cells lining the glandular elements of the tissue; these are the cells from which CaP might arise.

CONCLUSION

Constitutive expression of bioactivating enzymes confers the potential to convert a range of exogenous and/or endogenous agents to reactive species capable of inducing DNA damaging events. These findings suggest an organ capability for pro‐carcinogen activation that could play an important role in the etiology of human CaP. Prostate 70: 1586–1599, 2010. © 2010 Wiley‐Liss, Inc.
Species specificity of the complement inhibitor compstatin investigated by all‐atom molecular dynamics simulations
Authors: Tamamis Phanourios , Morikis Dimitrios , Floudas Christodoulos A. , Archontis Georgios
Published: June 2010

The development of compounds to regulate the activation of the complement system in non‐primate species is of profound interest because it can provide models for human diseases. The peptide compstatin inhibits protein C3 in primate mammals and is a potential therapeutic agent against unregulated activation of complement in humans but is inactive against nonprimate species. Here, we elucidate this species specificity of compstatin by molecular dynamics simulations of complexes between the most potent natural compstatin analog and human or rat C3. The results are compared against an experimental conformation of the human complex, determined recently by X‐ray diffraction at 2.4‐Å resolution. The human complex simulations provide information on the relative contributions to stability of specific C3 and compstatin residues. In the rat simulations, the protein undergoes reproducible conformational changes, which eliminate or weaken specific interactions and reduce the complex stability. The simulation insights can be used to design improved compstatin‐based inhibitors for human C3 and active inhibitors against lower mammals. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Metamaterial inspired enhanced far‐field transmission through a subwavelength nano‐hole
Authors: Boratay Alici Kamil , Ozbay Ekmel
Published: June 2010

In the present study, we first demonstrate the polarization and orientation dependent transmission response of split ring resonators at the infrared and visible band. Then, we numerically demonstrate a configuration for the enhancement of power passing through an electrically small hole. By using deep subwavelength optical split ring resonator antennas and couplers we achieved a 400‐fold enhanced transmission from a subwavelength aperture area of the electrical size λ2/25. The power was transmitted to the far field with 3.9 dBi directivity at 300 THz. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vitamin C increases the fecal fat excretion by chitosan in guinea‐pigs, thereby reducing body weight gain
Authors: Jun S. C. , Jung E. Y. , Kang D. H. , Kim J. M. , Chang U. J. , Suh H. J.
Published: June 2010

The aims of this study were to investigate the antiobesity properties of chitosan on its own, as well as in the presence of vitamin C, in vivo. Hartley guinea‐pigs were divided into Control (normal diet), F‐control (high fat diet), Chitosan (high fat diet with 5.0% chitosan) and Chito‐vit C (high fat diet with 5.0% chitosan containing 0.5% vitamin C) groups, respectively. The effects of chitosan, both alone and in the presence of vitamin C, on body weight, total fecal weight, fecal composition and plasma lipid level were studied for 5 weeks. The results of this study indicated that the fat‐binding and water‐holding capacity of chitosan might decrease body weight by reducing the absorption of cholesterol and fat, subsequently increasing total fecal weight, fecal fat excretion and fecal water excretion. Vitamin C increased the fecal fat excretion by chitosan in guinea‐pigs, thereby reducing body weight gain. Copyright © 2010 John Wiley & Sons, Ltd.
Partial interdigitation of lipid bilayers
Authors: Mavromoustakos Thomas , Chatzigeorgiou Petros , Koukoulitsa Catherine , Durdagi Serdar
Published: June 2010

A methodology has been developed to detect partial interdigitation of lipid bilayers when a bioactive molecule is intercalated between the polar, interface, or hydrophobic segments. This methodology uses the easily accessible differential scanning calorimetry (DSC) technique as a screening one and the increase of ΔH due to the incorporated drug in lipid bilayers as a diagnostic thermodynamic parameter. The combined use of X‐ray diffraction and Raman spectroscopy complement and confirm the provided by DSC information as it is shown in three classes of molecules, namely AT1 antagonists, vinca alkaloids, and anesthetic steroids. For the two classes of molecules, AT1 antagonists and vinca alkaloids, their presence in lipid bilayers results in the increase of ΔH and it is accompanied by the increase of trans:gauche ratio and the decrease of d‐spacing as depicted by Raman spectroscopy and small‐angle X‐ray diffraction correspondingly, confirming the predictive ability of DSC experiments. When an anesthetic steroid is incorporated in lipid bilayers, neither increase of ΔH nor decrease of d‐spacing was observed, confirming again the DSC results that show the absence of partial interdigitation of this class of molecules. Molecular dynamics simulations have been carried out for a representative system [(5S)‐1‐benzylo‐5‐(1H‐benzimidazol‐1‐ylo‐methylo)‐2‐pyrrolidinone (MMK3) ligands at 1,2‐dimyristoyl‐sn‐glycero‐3‐phosphocholine (DMPC) lipid bilayer], and the results confirmed the experimental findings. The change of distance at z‐axis of oxygen atoms at head group of lipid molecule has been measured throughout the simulations. Statistical analysis has shown ∼8.8 Å interdigitation. Derived computational results are encouraging and can be performed to another ligand/lipid system. The development of a theoretical methodology will lead to advance the field and save a valuable time and effort. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Carbon dioxide in aqueous environment—A quantum mechanical charge field molecular dynamics study
Authors: Moin Syed Tarique , Pribil Andreas B. , Lim Len Herald V. , Hofer Thomas S. , Randolf Bernhard R. , Rode Bernd M.
Published: June 2010

Structure and dynamics of a carbon dioxide molecule in water were studied by an ab initio quantum mechanical charge field molecular dynamics (QMCF‐MD) simulation. Radial distribution functions, angular distribution functions, and coordination number distributions as well as dynamical data such as mean ligand residence time and vibrational spectra were utilized for the evaluation of physico–chemical properties of hydrated CO2. These data served for an assessment of hydrogen bonding between solute and solvent molecules. All the results evaluated were compared with available experimental results leading to a good agreement between theoretical and experimental data. The average lifetime of hydrogen bonding between H2 O and CO2 resulted as 0.61 ps, which is higher than the hydrogen bonding lifetime of pure water. The vibrational frequencies were also calculated for all the modes of hydrated CO2 to demonstrate the influence of solvent molecules on the IR spectrum of the solute. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Methanol vinylation mechanism in the KOH/DMSO/CH3OH/C2H2 system
Authors: Vitkovskaya Nadezhda M. , Larionova Elena Yu. , Kobychev Vladimir B. , Kaempf Natalia V. , Trofimov Boris A.
Published: June 2010

The reaction mechanism of methanol vinylation with acetylene involving a nondissociated KOH molecule was studied using the MP2/6‐311++G**//HF/6‐31+G* approach with the DMSO molecule explicitly included into reaction system. The whole conversion cycle of methanol vinylation including active nucleophile generation, bonding of the latter to the acetylene moiety yielding an intermediate carbanion, final methyl vinyl ether formation, and potassium hydroxide regeneration could be realized in the coordination shell of nondissociated KOH. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Geometry and vibrational frequencies of the helical polypeptide complexes with ligand molecules
Authors: Makshakova Olga , Chachkov Denis , Ermakova Elena
Published: June 2010

The complexes of alpha helical polypeptides and individual molecules of water, acetonitrile, and 1,4‐dioxane have been investigated. We used 16‐mer of polyalanine (PA), polyglutamic acid (PGA) and poly‐γ‐benzyl‐L‐glutamate (PBG). Full geometry optimization was performed for polypeptides and their complexes with ligands, each structure has been characterized by the vibrational analysis and the interaction energy including the correction for zero point vibrational energy. Polyalanine creates by single complex with water molecule, acetonitrile, and dioxane. Polyglutamic acid forms five different complexes with water molecule, and three complexes with acetonitrile and two complexes with dioxane. Two complexes of poly‐γ‐benzyl‐L‐glutamate with each ligand were found. Carbonyl oxygen of PGA and PBG confirms its strong acceptor character by participation in formation of all obtained complexes with water and acetonitrile. The long side chains of PGA and PBG aid the formation of complexes with two hydrogen bonds where ligand molecule bridges two polar sites of polypeptide. Most of complexes of dioxane with polypeptides are produced due to weak hydrogen bonds of type CH···O. Strong shifts for the stretching vibrations of the interacting group of polypeptides and ligands under the complex formation are detected. Obtained frequencies are in a good agreement with known experimental data. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
New nonsteroidal anti‐inflammatory molecules with reduced photodegradation side effects and enhanced COX‐2 selectivity
Authors: Musa Klefah A. K. , Palwai Viraja R. , Eriksson Leif A.
Published: June 2010

Nonsteroidal anti‐inflammatory drugs (NSAIDs) are widely used as antipyretic, analgesic, and anti‐inflammatory agents. However, they are also associated with a range of side effects, from phototoxicity due to excited state induced decarboxylation to severe conditions in the gastrointestinal tract caused by inhibition of the COX‐1 isoform of the target cyclooxygenase enzyme. In the current work, new derivatives of the three NSAIDs ketoprofen, ibuprofen, and naproxen were designed. Their photochemistry was explored using hybrid‐density functional theory (B3LYP/6‐31G(d,p)) and time‐dependent (TD) DFT, showing that the compounds will have significantly reduced propensity to decarboxylate from the first excited triplet state. In addition, docking studies were carried out for these new molecules to explore their activity and selectivity toward the two isoforms of the COX enzyme. The results show that most compounds have increased activity toward the COX enzymes, and in general are more selective toward the COX‐2 target isoform. The results from this study suggest that the new modified molecules could be used in the future as NSAIDs with considerably reduced side effects. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Modeling solvatochromism of Nile red in water
Authors: Murugan Natarajan Arul , Rinkevicius Zilvinas , Ågren Hans
Published: June 2010

Spurred by the pioneering modeling studies of Sylvio Canuto on absorption spectra and solvatochromic shifts of organic molecules in polar and nonpolar solvents, we report in this work a computational study for the common optical dye probe Nile red (NR) to elucidate the origin of its absorption shift between gas phase and aqueous solution. The Car‐Parrinello molecular dynamics (CPMD) technique is used for gas phase NR, whereas for NR in water solvent, a hybrid quantum mechanics‐molecular dynamics (CPMD‐QM/MM) approach has been utilized. For the configurations obtained from CPMD and CPMD‐QM/MM, the absorption spectrum has been calculated using the INDO/CIS method as implemented in the ZINDO program. Different solvation shells for NR in water have been defined based on solute‐all‐atoms and solvent center of mass radial distribution function (g(rX–O)rdf). The electronic excitation energies for these solvation shells were calculated in a systematic way to evaluate their individual contributions. In addition, calculations of absorption spectra were performed for NR (excluding solvent molecules) obtained from CPMD‐QM/MM calculations to isolate the contribution to the solvatochromic shift just due to solvent‐induced geometrical change. Interestingly, this geometrical change in NR itself contributes as much as 50 nm to the solvatochromic shift. The calculated λmax for gas phase is around 488 nm and is comparable to the values reported for NR in nonpolar solvents, whereas the inclusion of solvent molecules in the hydration shell yields a λmax of 565 nm which contributes to almost 77 nm of the solvatochromic shift. The inclusion of solvent molecules up to the fourth solvation shell in the g(rX–O) rdf yields λmax of 596 nm which is in good agreement with the experimentally reported value 593 nm. The change in λmax due to inclusion of the fourth solvation shell is only 1 nm, indicating that the spectrum has converged with respect to the solvent effect. Overall, this study suggests that the combined use of CPMD‐QM/MM and ZINDO can be successfully used to model and to interpret solvatochromic and thermochromic behavior of NR and other organic dye molecules. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Nonadiabatic effects in the irradiation of ethylene
Authors: Wang Zhi‐Ping , Dinh Phuong Mai , Reinhard Paul Gerhard , Suraud Eric , Zhang Feng Shou
Published: June 2010

In the framework of the time‐dependent local density approximation, applied to valence electrons, coupled nonadiabatically to molecular dynamics of ions, the irradiations of ethylene by laser and fast charged projectiles are studied. We find that the Coulomb fragmentation sensitively depends on the laser frequency and on the charge of the projectile. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Isomerization effects on chemical shifts and spin‐spin coupling constants of polyacetylene chains: A GIAO‐DFT study
Authors: Colherinhas G. , Fonseca T. L. , Georg H. C. , Castro M. A.
Published: June 2010

Using the gauge‐including atomic orbitals approach with B3LYP exchange‐correlation functional in combination with the 6‐311++G(2d,2p) basis set, we have calculated the 13C chemical shifts [Δσ] and 13C13C indirect spin‐spin coupling constants [J(C,C)] for the series of isolated planar polyacetylene chains C2nH2n+2, from n = 2 up to n = 11. For both cis and trans isomers, infinite polymer values can be estimated from converged chemical shifts in the central unit of each isomer. The theoretical model predicts the chemical shift difference between the cis and trans forms of 10.28 ppm, in very good concordance with experimental result. The 1J(CC) and 1J(CC) calculated values are more geometry‐dependent but they exhibit notable regularity typical for such systems as the size of chain is increased. Variations between 1J(CC) and 1J(CC) in the central unit of the C22H24 chain are estimated around 11 Hz, independent of isomeric form. It is found for both 1J(CC) and 1J(CC) that variations between the cis and trans forms are in the range of 3–4 Hz, indicating also a distinction of the isomeric form. In addition, our results show that the presence of a structural change on these conjugated backbones has marked influence on the chemical shifts. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Filtered stress autocorrelation functions of liquid water models
Authors: Medina J. S. , Prosmiti R. , Villarreal P. , Delgado‐Barrio G. , Alemán J. V. , González B. , Winter G.
Published: June 2010

Pressure autocorrelation functions of two models, SPC/E and SPC/Fw, of pure liquid water are presented. Periodic boundary condition simulations, in the microcanonical ensemble (NVE), of 256 molecules at room temperature are accomplished for both models. Green‐Kubo relations are used over the stress tensor time series to extract viscosity properties of the system. Filtering of noise and signal in the numerical data is considered. Three steps are discussed to reach relevant physical data pertaining to transport coefficients calculations: (1) removing noise via Savitzky‐Golay filters to smooth signals, (2) fitting data by combining Kohlrausch type functions, (3) separating low frequency from high frequency behavior. On the latter resides the essential difference between rigid and flexible models. Considerations about the stress tensor structure in flexible case, and the physical meaning each part holds, are explained and used to show similarities in low frequency (librational/translational and cluster) motions present in both models. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Determination of nandrolone metabolites in human urine: comparison between liquid chromatography/tandem mass spectrometry and gas chromatography/mass spectrometry
Authors: Buiarelli Francesca , Giannetti Luigi , Jasionowska Renata , Cruciani Claudia , Neri Bruno
Published: June 2010

Nandrolone (19‐nortestosterone) is an androgenic anabolic steroid illegally used as a growth‐promoting agent in animal breeding and as a performance enhancer in athletics. Therefore, its use was officially banned in 1974 by the Medical Commission of the International Olympic Committee (IOC). Following nandrolone administration, the main metabolites in humans are 19‐norandrosterone, 19‐norethiocolanolone and 19‐norepiandrosterone, and their presence in urine is the basis of detecting its abuse. The present work was undertaken to determine, in human urine, nandrolone metabolites (phase I and phase II) by developing and comparing multiresidue liquid chromatography/tandem mass spectrometry (LC/MS/MS) and gas chromatography/mass spectrometry (GC/MS) methods. A double extraction by solid‐phase extraction (SPE) was necessary for the complete elimination of the interfering compounds. The proposed methods were also tested on a real positive sample, and they allow us to determine the conjugated/free fractions ratio reducing the risk of false positive or misleading results and they should allow laboratories involved in doping control analysis to monitor the illegal use of steroids. The advantages of LC/MS/MS over GC/MS (which is the technique mainly used) include the elimination of the hydrolysis and derivatization steps: it is known that during enzymatic hydrolysis several steroids can be converted into related compounds and deconjugation is not always 100% effective. The validation parameters for the two methods were similar (limit of quantification (LOQ) <1 ng/mL and percentage coefficient of variance (CV%) <16.4), and both were able to confirm unambiguously all the analytes, thus confirming the validity of both techniques. Copyright © 2010 John Wiley & Sons, Ltd.
Semi‐online nanoflow liquid chromatography/matrix‐assisted laser desorption ionization mass spectrometry of synthetic polymers using an octadecylsilyl‐modified monolithic silica capillary column
Authors: Watanabe Takehiro , Nakanishi Keisuke , Ozawa Tomoyuki , Kawasaki Hideya , Ute Koichi , Arakawa Ryuichi
Published: June 2010

We have designed a semi‐online liquid chromatography/matrix‐assisted laser desorption/ionization mass spectrometry (LC/MALDI‐MS) system to introduce eluent from a octadecylsilyl (ODS) group modified monolithic silica capillary chromatographic column directly onto a sample plate for MALDI‐MS analysis. Our novel semi‐online system is useful for rapidly and sensitively examining the performance of a monolithic capillary column. An additional advantage is the small elution volume of a monolithic capillary column, which allows delicate eluents, such as 1,1,1,3,3,3,‐hexafluoroisopropyl alcohol (HFIP), to be used to achieve cost‐effective analysis. Using the semi‐online LC/MALDI‐MS system, chromatographic separation of polymers by the monolithic column with different eluents was studied. Separation of poly(methyl methacrylate) and Nylon 6/6 showed that the column functioned via size‐exclusion separation when tetrahydrofuran or HFIP eluent was used. On the other hand, the separation behavior of Nylon 11 indicated a reversed‐phase mode owing to the interaction of the polymer with the modified ODS group in the column. Using tetrahydrofuran/methanol (1:1, v/v) as the eluent, the LC/MALDI‐MS spectra of poly(lactic acid), which contains both linear and cyclic polymer structures, showed that the column could separate the hydrophobic cyclic polymer and elute it out relatively slowly. The monolithic column functions basically via size‐exclusion separation; the reversed‐phase separation by interaction with the ODS functions may have less influence on column separation. The semi‐online monolithic capillary LC/MALDI‐MS method we have developed should provide a means of effectively analyzing synthetic polymers. Copyright © 2010 John Wiley & Sons, Ltd.
Sensitive liquid chromatography/tandem mass spectrometry assay for absolute quantification of ITIH4‐derived putative biomarker peptides in clinical serum samples
Authors: van den Broek Irene , Sparidans Rolf W. , Schellens Jan H. M. , Beijnen Jos. H.
Published: June 2010

To explore the potential of peptide fragments derived from inter‐α‐trypsin inhibitor heavy chain‐4 (ITIH4) as serum markers for different cancer types, sensitive and specific analytical assays are required. Liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS) would be suitable; however, a previously developed method for quantification of eight ITIH4 fragments (ITIH4‐21, ‐22, ‐25, ‐26, ‐27, ‐28, ‐29 and ‐30) was found to be insensitive for clinical use. A more sensitive LC/MS/MS assay has now been developed and validated, which was further optimized to facilitate analyses of large sets of clinical serum samples. Benefits compared to the previous method include reduction of sample volume (100 µL), omission of protein precipitation and evaporation and transferring solid‐phase extraction (SPE) to a 96‐well format. Chromatographic separation on an XBridge BEH300 C18 column, using a water/methanol gradient containing acetic acid, was coupled to triple quadrupole mass spectrometric detection, applying heated electrospray ionization. Method validation revealed deviations from nominal concentrations below 10.1% and intra‐ and inter‐assay precisions below 17.4 and 20.0%, respectively, at the lower limit of quantification (LLOQ) for all peptides. The reported changes resulted in more rapid and efficient analyses and reduced LLOQs for the six less abundant peptides (1.2; 1.0; 1.2; 2.0; 2.0 and 2.0 ng/mL vs. 2.1; 2.0; 2.5; 2.6; 2.2 and 2.4 ng/mL for ITIH4‐21, ‐22, ‐25, ‐27, ‐28 and ‐29, respectively). The method has shown its applicability by quantifying all peptides in appropriate concentration ranges in serum from healthy volunteers and application to clinical samples from breast cancer patients. Copyright © 2010 John Wiley & Sons, Ltd.
Extra virgin (EV) and ordinary (ON) olive oils: distinction and detection of adulteration (EV with ON) as determined by direct infusion electrospray ionization mass spectrometry and chemometric approaches
Authors: de O. Alves Júnia , Neto Waldomiro B. , Mitsutake Hery , Alves Paulo S. P. , Augusti Rodinei
Published: June 2010

Extra virgin (EV), the finest and most expensive among all the olive oil grades, is often adulterated by the cheapest and lowest quality ordinary (ON) olive oil. A new methodology is described herein that provides a simple, rapid, and accurate way not only to detect such type of adulteration, but also to distinguish between these olive oil grades (EV and ON). This approach is based on the application of direct infusion electrospray ionization mass spectrometry in the positive ion mode, ESI(+)‐MS, followed by the treatment of the MS data via exploratory statistical approaches, PCA (principal component analysis) and HCA (hierarchical clustering analysis). Ten distinct brands of each EV and ON olive oil, acquired at local stores, were analyzed by ESI(+)‐MS and the results from HCA and PCA clearly indicated the formation of two distinct groups related to these two categories. For the adulteration study, one brand of each olive oil grade (EV and ON) was selected. The counterfeit samples (a total of 20) were then prepared by adding assorted proportions, from 1 to 20% w/w, with increments of 1% w/w, of the ON to the EV olive oil. The PCA and HCA methodologies, applied to the ESI(+)‐MS data from the counterfeit (20) and authentic (10) EV samples, were able to readily detect adulteration, even at levels as low as 1% w/w. Copyright © 2010 John Wiley & Sons, Ltd.
Vision‐based robotic person following under light variations and difficult walking maneuvers
Authors: Tarokh Mahmoud , Merloti Paulo
Published: June 2010

The paper addresses the problem of robotic person following indoors and outdoors with significant light variation such as moving from sunny areas into shade and difficult walking maneuvers such as jumping to the side or making sharp turns. These are achieved through certain image processing techniques and by real‐time control of camera parameters affecting the light exposure, i.e., camera gain and shutter speed. Several strategies are also formulated and integrated to quickly recognize and segment the person from the environment during difficult walking maneuvers. The centroid of a person's image, which is a critical quantity for person following, is determined using a new method based on aggregation of the detected regions and their color characteristics. In addition to the camera exposure control, the camera pan and tilt and the robot speed and steering are controlled using the characteristics of the detected person's image such as mass (area) and centroid. Although the emphasis of the paper is on person following, the same techniques can be adapted for following moving objects such as another robot or a car. The system has been implemented on a Segway robotic platform that has been equipped with a camera, an onboard computer, loudspeakers, game pad, etc. Extensive trials have been carried out both indoors and outdoors, and a video has been prepared that shows person following under a variety of conditions. © 2010 Wiley Periodicals, Inc.
Comparison of the interannual and interdecadal variability of heavy flood characteristics upstream and downstream from dams in inversed hydrologic regime: Case study of Matawin River (Québec, Canada)
Authors: Fortier Catherine , Assani Ali A. , Mesfioui Mhamed , Roy André G.
Published: June 2010

Erected in 1930, the Matawin Dam caused an inversion of the hydrologic regime of the Matawin River: snow‐melt water in spring (April to June) is stored in the reservoir and then released in winter (January to March) to feed the hydroelectric generating stations built downstream on the Saint‐Maurice River. Thus, heavy floods occur upstream from the dam in spring but downstream in winter. We compared the interannual and interdecadal variability of the heavy flood characteristics (magnitude, duration, frequency and variability) both upstream (spring floods) and downstream (winter floods) from the dam during the 1934–1994 period. This comparison revealed that the principal change observed downstream from the dam translates into a strong increase in the duration (in days) of heavy floods. The average duration of these floods quintupled. This change in duration occurred around the mid‐1960s and thus led to a significant decrease in the magnitude, frequency and variability of heavy floods. It also altered the relationship between the climate indices and these fundamental characteristics (magnitude, frequency and duration). Downstream from the dam, the magnitude and frequency are positively correlated to the Atlantic multidecadal oscillation (AMO), whereas upstream they are negatively correlated to the same index. However, the AMO index is negatively correlated to the duration downstream from the dam, whereas upstream this characteristic is no longer significantly correlated to any climatic index.

Two factors have been invoked to explain this change observed downstream from the dam.

The cooling observed since the 1960s at the station located at the dam. However, this cooling was not observed on the scale of the entire watershed. This reduces its plausibility.

The increase in hydroelectric power production in the watershed after nationalization of hydroelectric power in 1962. This increase would be explained by the expansion of the market for hydroelectric power (national and international markets). Before nationalization, the hydroelectric power produced in the watershed was intended only for regional industries.

Copyright © 2010 John Wiley & Sons, Ltd.
Ökobilanzierung von Baustahl
Authors: Kreißig Johannes , Hauke Bernhard , Kuhnhenne Markus
Published: June 2010

Die mit der überarbeiteten Bauproduktenverordnung neu hinzu kommende Basisforderung nach nachhaltiger Nutzung der natürlichen Ressourcen muss zukünftig bei der europäisch harmonisierten Vermarktung von Bauprodukten berücksichtigt werden. Bauwerke müssen entsprechend entworfen, errichtet und rückgebaut werden. Weiterhin ist zu gewährleisten, dass das Bauwerk, seine Baustoffe und Teile nach dem Rückbau recycelt werden können, das Bauwerk dauerhaft ist und für das Bauwerk umweltfreundliche Rohstoffe und Sekundärbaustoffe verwendet werden.

In diesem normativen Kontext kommt der Ökobilanzierung von Baustoffen eine wachsende Bedeutung zu. Auch für die Nachhaltigkeitsbewertung von Gebäuden, z. B. nach dem DGNB Gütesiegel, sind qualifizierte Umweltdaten der verwendeten Baustoffe eine wichtige Eingangsgröße. Dieser Beitrag beschreibt die Ökobilanzierung von Baustoffen im Allgemeinen und von Baustahl im Speziellen.

Eco‐balance of structural steel. With the upcoming Construction Product Requirements (CPR) the new basic requirement of sustainable utilization of natural resources must also be obeyed by the harmonized European market for construction products. Buildings must be designed, constructed and dismantled accordingly. Furthermore it must be assured that the buildings, the materials and members they are made of can be recycled, that the building is durable and that only environmentally sound raw materials and products are employed.

Within this normative context eco‐balancing of construction materials has a growing importance. Also for the sustainability assessment of buildings, e. g. according to the DGNB label, qualified eco‐data of the employed construction materials are an important input. This paper describes the eco‐balancing of construction materials in general and of structural steel in particular.
Zuschrift zu: Ungermann, D., Kalameya, J., Brune, B.: Zur Tragfähigkeit von druck‐ und biegebeanspruchten C‐Profilen aus Stahl.
Authors: Hanf Manfred
Published: June 2010

[Stahlbau 78 (2009), H. 11, S. 822–831 10.1002/stab.200910098]
Timing analysis of scenario‐based specifications using linear programming
Authors: Li Xuandong , Pan Minxue , Bu Lei , Wang Linzhang , Zhao Jianhua
Published: June 2010

Scenario‐based specifications (SBSs), such as UML interaction models, offer an intuitive and visual way of describing design requirements, and are playing an increasingly important role in the design of software systems. This paper presents an approach to timing analysis of SBSs expressed by UML interaction models. The approach considers more general and expressive timing constraints in UML sequence diagrams (SDs), and gives a solution to the reachability analysis, constraint conformance analysis and bounded delay analysis problems, which reduces these problems into linear programs. With the synchronous interpretation of the SD compositions, the timing analysis algorithms in the approach form a decision procedure for a class of SBSs where any loop in any path is time‐independent of the other parts in the path. These algorithms are also a semi‐decision procedure for general SBSs with both the synchronous and asynchronous composition semantics. The approach also supports bounded timing analysis of SBSs, which investigates all the paths in the bound limit one by one, and performs the timing analysis for each finite path by linear programming. A tool prototype has been developed to support this approach. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of microcystin and complex cyanobacterial samples on the growth and oxidative stress parameters in green alga Pseudokirchneriella subcapitata and comparison with the model oxidative stressor—herbicide paraquat
Authors: Bártová Kateřina , Hilscherová Klára , Babica Pavel , Maršálek Blahoslav , Bláha Luděk
Published: June 2010

Oxidative stress is one of the biochemical mechanisms involved in toxicity of cyanobacterial toxins microcystins (MC), but its role in the effects of complex water blooms is elusive. The aim of this study was to investigate effects of pure MCs and different complex mixtures of cyanobacterial metabolites on the growth and biochemical markers of oxidative stress and detoxification in green alga Pseudokirchneriella subcapitata. Pure MCs at high concentrations (300 μg/L) had no effects on the growth of P. subcapitata (up to 10 day exposures) but stimulated activity of glutathione reductase (GR) after short 3 and 24 h exposures. Other biomarkers (levels of glutathione, GSH, and activities of glutathione‐S‐transferase, GST, and glutathione peroxidase, GPx) were not affected by pure MCs). Crude extract of the laboratory culture of cyanobacteria Microcystis aeruginosa (containing 300 μg/L of MCs) had no effects on algal growth or any of the biomarkers. Weak growth stimulations after 4–7 days were observed after exposures to the growth‐spent medium of the M. aeruginosa culture, which also inhibited activities of GST after prolonged exposures. Other investigated parameters (reduced GSH and activity of GPx) were not affected by any of the cyanobacterial samples. The results were compared with effects of model oxidative stressor herbicide paraquat, which exhibited variable effects on both algal growth and biomarkers (decrease in reduced GSH, stimulations of GR). Taken together, although pure MCs induce oxidative stress in green alga, the effects of cyanobacterial mixtures, which are more relevant to the natural situation, are more complex and they differ from the pure toxin. High variability in the biochemical responses to the oxidative stress makes the interpretation of results complicated, which limits the use of these biomarkers as early warnings of toxicity under natural conditions. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2011.
Morphological alterations of Vero cell exposed to coplanar PCB 126 and noncoplanar PCB 153
Authors: Shen Kaili , Shen Chaofeng , Chen Lei , Chen Xincai , Chen Yingxu
Published: June 2010

Polychlorinated biphenyls (PCBs) are widespread, persistent environmental contaminants that display a complex spectrum of toxicological properties. Exposure to PCBs has been associated with morphological anomalies in cell cultures. However, most mechanistic studies of PCBs' toxic activity have been focused on coplanar congeners. It is of importance to determine whether PCB treatment would influence cell configuration and whether these changes would depend on the structural characteristics of PCBs. In this study, we investigated cell morphological alteration in Vero cell cultures after exposure to coplanar PCB 126 and noncoplanar PCB 153. The survival of Vero cells was measured through the MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) test. Cytotoxicity results suggested that PCB congeners had a toxic, antiproliferative effect on Vero cells. Morphological studies described structural modifications and provided evidence that apoptosis might be the main cell death pathway in PCB 153‐treated cells. The comparison between PCB 126 and PCB 153 indicated that the cell death mechanisms involved in coplanar or noncoplanar PCB congener exposure were different in Vero cells. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.
In vivo studies on the immunotoxic effects of microcystins on rabbit
Authors: Yuan Gailing , Xie Ping , Zhang Xuezhen , Tang Rong , Gao Yu , Li Dapeng , Li Li
Published: June 2010

Microcystins (MCs) are the toxic molecules produced by common cyanobacterium in freshwater blooms. Their toxicities raise severe health issues in livestock and human beings. In current study, the immunotoxic effects of MC‐LR were investigated in rabbit through evaluating the dynamics of white blood cell (WBC) numbers and cytokine production such as interleukin‐3 (IL‐3), IL‐4, IL‐6, interferon‐γ (IFN‐γ), tumor necrosis factor‐α (TNF‐α). MCs at the high dose (50 μg MC‐LReq kg−1) significantly induced increase in the WBC number but decrease in the Th1 (IFN‐γ, TNF‐α) and Th2 (IL‐3, IL‐4, IL‐6) production. In the low dose group(12.5 μg MC‐LReq kg−1), the number of WBC and the production of IFN‐γ, IFN‐α, IL‐4, IL‐3, and IL‐6 increased gradually in first 12 h, reach the peaks at 12 h, and dropped after 24 h. Significantly positive correlations were found between the cytokines production of IL‐4 and IL‐6, IFN‐γ and IFN‐α, or IL‐4 and IFN‐γ. In conclusion, MC‐LR is able to disturb the rabbit immune system and there exists time‐dose response relationship in the MC‐LR‐eliciting perturbation, which probably give a better insight into investigating the immunotoxicity mechanisms of MCs in vivo. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.
Detection of mutagens and BaPMO inducers in river water using the Blue Cotton adsorption technique
Authors: Britvić Smiljana , Hackenberger Branimir K. , Jarić Davorka , Stepić Sandra
Published: June 2010

Induction of Mixed Function Oxidase (MFO) activity and bioactivation potential were measured in experimental carp and in native fish species from two rivers with different pollution level (Sava and Mrežnica). The experimental carp were intraperitoneally exposed to various water volume equivalents of Blue Cotton extracts from both rivers. The induction of MFO measured as a Benzo(a)pyrene monooxygenase (BaPMO) activity was increased up to 9.3‐fold in experimental carp and up to 11.3‐fold in native fish from Sava River, whereas the values from Mrežnica River showed only a slight increase when compared with the control (highest increase of 1.8‐fold in nose carp). Accordingly, bioactivation potential using modified Ames test was higher in both experiments with Sava River. Both measured parameters in experimental carp increased in a dose‐dependent manner in accordance to river volume equivalents. Different induction potential of native fish species comparable between two rivers confirmed the known possibility of their usage in biomonitoring studies. These results give qualitatively a new support to the idea of using Blue Cotton extraction technique combined with induction of MFO activity and Ames test in fish as a good biomarker for assessing risk of exposure to mutagens/carcinogens such as Polycyclic Aromatic Hydrocarbons (PAHs), especially due to the simplicity and cost‐effectiveness of these methods. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.
Fetal breathing is associated with increased umbilical blood flow
Authors: Nyberg M. K. , Johnsen S. L. , Rasmussen S. , Kiserud T.
Published: June 2010

Objectives

In humans, fetal breathing movements affect blood velocities in the umbilical vein and artery, but it is not known whether fetal respiratory activity is associated with increased fetal blood flow through the placenta. We therefore tested this hypothesis in the present study.

Methods

One‐hundred and ten women with low‐risk singleton pregnancies were each examined three times by ultrasound during the second half of pregnancy. Fetal heart rate, umbilical artery blood velocity, umbilical vein diameter and blood velocity, and umbilical blood flow at the placental end were determined during fetal rest and fetal respiratory movements.

Results

Based on 330 observations obtained during fetal rest or breathing activity, no difference was found in the mean fetal heart rate (beats per minute (bpm)) during rest compared with breathing (142 bpm vs. 142 bpm, respectively). Although fetal breathing affected the umbilical artery waveform, there was no difference in the mean time‐averaged maximum velocity between rest and breathing: 26.6 (95% CI, 25.1–28.3) cm/s vs. 28.9 (95% CI, 27.2–30.7) cm/s, respectively. The umbilical vein was 27% greater in cross‐sectional area and the blood velocity 9% higher during breathing, resulting in a 42% increase in mean umbilical blood flow: 121.8 (95% CI, 109.5–135.0) mL/min at rest vs. 173.0 (95% CI, 158.0–188.6) mL/min during breathing. Venous velocity was calculated from recordings of mean duration 3.7 s at rest and 6.2 s of respiratory activity. Gestational age did not influence the relationship.

Conclusion

Fetal breathing is associated with increased umbilical blood flow during the second half of pregnancy. Umbilical vein distension during breathing suggests active endocrine regulation. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Grade and symmetry of normal fetal cortical development: a longitudinal two‐ and three‐dimensional ultrasound study
Authors: Pistorius L. R. , Stoutenbeek P. , Groenendaal F. , de Vries L. , Manten G. , Mulder E. , Visser G.
Published: June 2010

Objectives

Recent studies have shown the capability of ultrasound to demonstrate fetal cortical development. For practical application, it would be useful to have more insight into the physiological progress of cortical folding. A longitudinal study was undertaken to grade fetal cortical development and to study physiological asymmetry by means of a simple scoring system. The reproducibility of the scoring system and the differences between two‐dimensional (2D) and three‐dimensional (3D) ultrasound were also examined.

Methods

A cohort of 28 patients was examined by 2D and 3D ultrasound from 20 to 40 weeks of gestation. The development of selected fissures, sulci and cortical areas were graded from 0 to 5. One examination per week of gestation was randomly selected for evaluation of intraobserver and interobserver variation.

Results

Two‐hundred and fifteen ultrasound examinations were performed in 28 patients. The development of the different cortical areas is presented. The intraobserver and interobserver agreement for assessment of grade was good. Asymmetry was common between 24 and 28 weeks, especially in female fetuses. The right parieto‐occipital fissure tended to be more advanced and the left calcarine and cingulate sulci tended to be more advanced. No clinically or statistically significant differences were found between 2D and 3D ultrasound.

Conclusions

Evaluation of cortical development by means of a simple scoring system is feasible and reproducible. Asymmetrical development of sulci, previously only described in vitro, has now also been demonstrated in vivo. 3D ultrasound was equally accurate and repeatable and no more time consuming than 2D ultrasound. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Flächeneinfluss bei der PACVD‐Beschichtung
Authors: Martin Jasmin , Krell Lisa , Schnagl Johann , Stahl Karsten
Published: June 2010

In der Automobilindustrie werden wirtschaftliche und stabile Prozesse zur Beschichtung mit Hartstoffschichten für tribologische Anwendungen benötigt. Daher ist es erforderlich, den Einfluss der Beschichtungsparameter auf die Schichteigenschaften zu kennen. In vorliegender Untersuchung wird die Beschichtung mittels plasmaunterstützter chemischer Gasphasenabscheidung betrachtet. Hauptsächlich wird der Einfluss der in die Beschichtungskammer eingebrachten aktiven Fläche auf die Eigenschaften amorpher Kohlenstoffschichten (DLC) geprüft. Die Herstellung der Beschichtungen erfolgt in einer industriellen Beschichtungskammer bei einer Frequenz von 40 kHz, mit konstanter Bias Spannung und gleichbleibendem Kammerdruck.

Die Versuche bestätigen eine Korrelation zwischen aktiver Fläche und Stromdichte, wodurch auch die mechanischen und tribologischen Eigenschaften der DLC‐Schichten beeinflusst werden. Durch gezielte Regelung der Stromdichte wird es möglich, auch bei unterschiedlich großer aktiver Fläche gleichbleibende Schichteigenschaften zu erzielen und eine Verbesserung der Schichtqualität in Bezug auf ihren Verschleiß bei hochbelasteten Motorbauteilen zu erreichen.