bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma Methods for the Generation of Chemically Reactive Surfaces for Biomolecule Immobilization and Cell Colonization ‐ A Review
Authors: Siow Kim Shyong , Britcher Leanne , Kumar Sunil , Griesser Hans J. 
Published: August 2006

AbstractSummary: This review surveys methods for the fabrication, by plasma surface treatments or plasma polymerization, of polymeric surfaces and thin plasma polymer coatings that contain reactive chemical groups useful for the subsequent covalent immobilization, by solution chemical reactions or vapor phase grafting, of molecules or polymers that can exert bio‐specific interfacial responses. Surfaces containing amine, carboxy, hydroxy, and aldehyde groups are the subject of this review. Aminated surfaces have been fabricated using various plasma vapors or mixtures and have found wide use for bio‐interface applications. However, in many cases the amine surfaces have a rather limited shelf life, with post‐plasma oxidation reactions and surface adaptation leading to the disappearance of amine groups from the surface. Aging is a widespread phenomenon that often has not been recognized, particularly in some of the earlier studies on the use of plasma‐fabricated surfaces for bio‐interfacial applications, and can markedly alter the surface chemistry. Plasma‐fabricated surfaces that contain carboxy groups have also been well documented. Fewer reports exist on hydroxy and aldehyde surfaces prepared by plasma methods. Hydroxy surfaces can be prepared by water plasma treatment or the plasma polymerization of alkyl alcohol vapors. Water plasma treatment on many polymer substrates suffers from aging, with surface adaptation leading to the movement of surface modification effects into the polymer. Both hydroxy and aldehyde surfaces have been used for the covalent immobilization of biologically active molecules. Aging effects are less well documented than for amine surfaces. This review also surveys studies using such surfaces for cell colonization assays. Generally, these surface chemistries show good ability to support cell colonization, though the effectiveness seems to depend on the process vapor and the plasma conditions. Carboxylate co‐polymer surfaces have shown excellent ability to support the colonization of some human cell lines of clinical interest. Immobilization of proteins onto plasma‐carboxylated surfaces is also well established.XPS O/C ratios (00 emission) as a function of storage time, of plasma‐polymerized methyl methacrylate deposited at power levels of 5 and 40 W.magnified imageXPS O/C ratios (00 emission) as a function of storage time, of plasma‐polymerized methyl methacrylate deposited at power levels of 5 and 40 W.
Controlled Cell Attachment, Using Plasma Deposited Polymer Microstructures: A Novel Study of Cells‐Substrate Interactions
Authors: Sciarratta Vincenzo , Sohn Kai , Burger‐Kentischer Anke , Brunner Herwig , Oehr Christian 
Published: August 2006

AbstractSummary: Several actual developments in medical therapy are focussing on the potential of a surface‐dependent selection and proliferation of special cell types. For an improvement of biocompatibility it is interesting to understand the interactions between cells and material surfaces in order to create devices with the respective characteristics. In this paper the possibility to isolate three different tumor cells lines are studied: HEK293, RINm5f and KYM‐1. A procedure by means of plasma polymerization is demonstrated to create hydrophilic microstructures (precursor: AAc) on a hydrophobic (precursor: CHF3) substrate and shown to effectively select RINm5f cells. Moreover, by studying the interaction between culture media and deposited polymers, it is shown that Ca2+ ions and protein adsorption play a fundamental role in the cell‐substrate adhesion and proliferation.
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Anisotropy and vortex behaviour in BiSrCaCuO thin films and multilayers probed by columnar pinning centers
Authors: Raffy H. , Murrills C. D. , Pomar A. , Stiufiuc G. , Stiufiuc R. , Li Z. Z. 
Published: August 2006

AbstractIn this paper we review typical mixed state transport results obtained on a variety of Bi2Sr2Can –1Cun Oy thin films and artificial multilayers, which allowed us to cover the range from low to high anisotropy. The vortex behaviour, 2D or 3D, probed by the pinning properties of columnar defects, is shown to be highly dependant on the anisotropy, and therefore on the microstructure of the system. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Laser technologies applied to the fabrication and characterization of bulk Bi‐2212 superconducting materials for power applications
Authors: Angurel L. A. , Díez J. C. , de la Fuente G. F. , Gimeno F. , Lera F. , López‐Gascón C. , Martínez E. , Mora M. , Navarro R. , Sotelo A. , Andrés N. , Recuero S. , Arroyo M. P. 
Published: August 2006

AbstractLasers are adequate tools in the processing and characterization of materials. The Applied Superconductivity group at the Aragón Materials Science Institute has been applying different laser techniques in the processing, machining and characterization of bulk high temperature superconductors for high power applications. Textured bulk Bi‐2212 superconductors have been obtained using laser melting zone techniques. We have produced thin bars, monoliths and coatings on metallic and ceramic substrates. Ablation techniques have been used to machine the samples with the required shape for technological applications. And finally, optical techniques have been used as non‐destructive experiments to detect the location of hot‐spots and the positions where environmental degradation starts. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of zaltoprofen in human plasma by liquid chromatography with electrospray tandem mass spectrometry: application to a pharmacokinetic study
Authors: Lee Heon‐Woo , Seo Ji‐Hyung , Kim Yong‐Won , Jeong Seo‐Young , Lee Kyung‐Tae 
Published: August 2006

AbstractIn the present study, we developed a method coupling liquid‐liquid extraction (LLE) to high‐performance liquid chromatography (HPLC) with positive ion electrospray ionization tandem mass spectrometry (ESI‐MS/MS) to determine zaltoprofen levels in human plasma, using enalapril as internal standard (IS). The high sensitivity and specificity of MS/MS detection enabled the use of small plasma volumes (250 µL) and a simple LLE procedure. Furthermore, the short run‐times (2 min) involved are compatible with the requirements of large‐scale clinical studies. Ion acquisition was performed in multiple reaction monitoring (MRM) mode by monitoring the transitions m/z 299.3 > 225.0 for zaltoprofen and m/z 377.4 > 234.2 for the IS enalapril. The limit of detection (LOD) was 0.01 µg/mL and the lower limit of quantitation (LLOQ) was 0.05 µg/mL. The devised method was linear over the studied range (0.05–20 µg/mL), with r2 > 0.99 and a run‐time of 2 min. Intra‐day precisions fell in the range 2.0–13.8%, inter‐day precisions in the range 2.1–3.9%, and intra‐ and inter‐day accuracies in the range 102.8–114.1%. The described method provides a fast and sensitive analytical tool for zaltoprofen and was successfully applied to a 24‐subject pharmacokinetic study. Copyright © 2006 John Wiley & Sons, Ltd.
Development and validation of a liquid chromatography/tandem mass spectrometric method for the determination of 39 mycotoxins in wheat and maize
Authors: Sulyok Michael , Berthiller Franz , Krska Rudolf , Schuhmacher Rainer 
Published: August 2006

AbstractThis paper describes the first validated method for the determination of 39 mycotoxins in wheat and maize using a single extraction step followed by liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (LC/ESI‐MS/MS) without the need for any clean‐up. The 39 analytes included A‐ and B‐trichothecenes (including deoxynivalenol‐3‐glucoside), zearalenone and related derivatives, fumonisins, enniatins, ergot alkaloids, ochratoxins, aflatoxins and moniliformin. The large number and the chemical diversity of the analytes required the application of the positive as well as the negative ion ESI mode in two consecutive chromatographic runs of 21 min each. The solvent mixture acetonitrile/water/acetic acid 79 + 20 + 1 (v/v/v) has been determined as the best compromise for the extraction of the analytes from wheat and maize. Raw extracts were diluted 1 + 1 and were injected without any clean‐up. Ion‐suppression effects due to co‐eluting matrix components were negligible in the case of wheat, whereas significant signal suppression for 12 analytes was observed in maize, causing purely proportional systematic errors. Method performance characteristics were determined after spiking blank samples on multiple levels in triplicate. Coefficients of variation of the overall process of <5.1% and <3.0% were obtained for wheat and maize, respectively, from linear calibration data. Limits of detection ranged from 0.03 to 220 µg/kg. Apparent recoveries (including both the recoveries of the extraction step and matrix effects) were within the range of 100 ± 10% for approximately half of the analytes. In extreme cases the apparent recoveries dropped to about 20%, but this could be compensated for to a large extent by the application of matrix‐matched standards to correct for matrix‐induced signal suppression, as only a few analytes such as nivalenol and the fumonisins exhibited incomplete extraction. For deoxynivalenol and zearalenone, the trueness of the method was confirmed through the analysis of certified reference materials. Copyright © 2006 John Wiley & Sons, Ltd.
A method for measuring enthalpy of volatilization of a compound, ΔvolH, from dilute aqueous solution
Authors: Wang Tianshu 
Published: August 2006

AbstractThis study has developed a method for measuring the enthalpy of volatilization (ΔvolH) of a compound in a dilute solution via ion‐molecule reactions and gas‐phase analysis using selected ion flow tube mass spectrometry (SIFT‐MS). The ΔvolH/R value was obtained using an equation with three variant forms either from the headspace concentration of the solution or from individual product ion(s). Under certain experimental conditions, the equation has the simplest form ${\rm \Delta }_{{\rm vol}} H/R = - \ln \left( {{{i_n /I} \over {i_n^{\rm o} /I^{\rm o} }}} \right){\rm /(1/}T - {\rm 1/}T^{\rm o} {\rm )}$, where R is the gas constant (8.314 J · mol−1 · K−1), in and I are the respective product and precursor ion count rates, and T is the temperature of the solution. As an example, a series of 27.0 µmol/L aqueous solutions of acetone was analyzed over a temperature range of 25–50°C at 5°C intervals using H3O+, NO+ and O precursor ions, producing a mean ΔvolH/R value of 4700 ± 200 K. This corresponds with current literature values and supports the consistency of the new method. Notably, using this method, as long as the concentration of the solution falls into the range of Henry's law, the exact concentration does not have to be known and it can require only one sample at each temperature. Compared with previous methods which involve the measurement of Henry's law constant at each temperature, this method significantly reduces the number of samples required and avoids the labour and difficulties in preparing standard solutions at very low concentrations. Further to this, if the contents of a solution were unknown the measured ΔvolH/R from individual product ion(s) can help to identify the origin of the ion(s). Copyright © 2006 John Wiley & Sons, Ltd.
Mass spectral characterization of phloroglucinol derivatives hyperforin and adhyperforin
Authors: Sleno Lekha , Daneshfar Rambod , Eckert Gunter P. , Müller Walter E. , Volmer Dietrich A. 
Published: August 2006

AbstractActive phloroglucinol constituents ofHypericum perforatum(St. John's wort) extracts, hyperforin and adhyperforin, have been studied following ion activation using tandem mass spectrometry (MS/MS) and complemented by accurate mass measurements. These two compounds were readily analyzed as protonated and deprotonated molecules with electrospray ionization. MS/MS and MS3data from a quadrupole‐linear ion trap tandem mass spectrometer were employed to elucidate fragmentation pathways. Fourier transform ion cyclotron resonance measurements afforded excellent mass accuracies for the confirmation of elemental formulae of product ions formed via infrared multiphoton dissociation and sustained off‐resonance irradiation collision‐induced dissociation. Fragmentation schemes have been devised for the dissociation of hyperforin and adhyperforin in negative and positive ion modes. This information is expected to be especially valuable for the characterization of related compounds, such as degradation products, metabolites and novel synthetic analogs of hyperforin. Copyright © 2006 John Wiley & Sons, Ltd.
Predicting vicarious traumatization in those indirectly exposed to bushfires
Authors: Byrne Mitchell K. , Lerias Doukessa , Sullivan Nichole L. 
Published: August 2006

AbstractPost‐traumatic stress through indirect exposure to trauma can mimic the psychological experiences of direct victims. This is referred to as vicarious traumatization, an impairing condition that largely goes undetected in the general population. This study sought to describe this condition and predict those who may be at risk of developing this type of post‐traumatic stress. One hundred and fifteen participants from south‐east New South Wales (NSW) in Australia who had not experienced any direct exposure, loss or injury from the 2001–2002 NSW bushfires were interviewed using the Vicarious Traumatization Questionnaire, Impact of Events Scale and Coping Strategies Indicator. Results indicated that specific peri‐event, post‐event and pre‐event characteristics were able to predict at least 75 per cent of those who experienced vicarious traumatization resulting from the 2001–2002 NSW bushfires. This study was able to identify and describe vicarious traumatization in a sample of the general population. The importance of these results and the issues for further research are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
ADDITIONAL CONFIRMATION FOR THE EFFECT OF ENVIRONMENTAL LIGHT INTENSITY ON THE SEASONALITY OF HUMAN CONCEPTIONS
Authors: CUMMINGS DAVID R. 
Published: August 2006

Summary.Causality for the seasonality of human births, which affects populations wordwide, has been a profound mystery for nearly two centuries. Most explanations for seasonality fail because of inconsistent global application. In two previous studies, Cummings (2002, 2003) hypothesized that human reproduction has been responsive to changes in both seasonal environmental light intensity (surface luminosity) and photoperiod. Except at higher latitudes, photoperiod is of secondary importance to that of environmental light intensity. Because of a lack of data, the presence or lack of cloud cover is used as a general proxy for environmental light intensity. These studies show a positive correlation between conceptual seasonality and cloud cover on a worldwide basis, and propose that there is a delay between exposure to increased light and the onset of conceptions. This delay is three months at higher latitudes and one to two months for lower latitudes. Both studies suggest that an excellent means of hypothesis confirmation would be to provide one or more examples of how a seasonal change in cloud cover might alter the number of conceptions in subsequent months. The present study tests this hypothesis. The percentage of possible sunshine and averaged sunshine hours are used to investigate their influence on seasonality of births in Germany and the Netherlands. The evidence shows that a seasonal change in environmental light intensity preceded a change in the peak months for conceptions in Germany and the Netherlands. Although secondary influences are possible, the primary reason for this transition in peak conceptual months seems to be related to the seasonal changes in environmental light intensity for both countries. Although this transitional relationship was predicted in Cummings (2002, 2003), further research is required, especially with regard to more precise measurements of environmental light intensity and its physiological effect on the human endocrine system.
Alfvén modes in a two-species magnetoplasma with anisotropic perturbation pressure-fluid and kinetic calculations
Authors: ALTMAN C. , SUCHY K. 
Published: August 2006

AbstractThe octic fluid dispersion equation, the kinetic Boltzmann–Vlasov equation and the MHD (scalar pressure) analysis, programmed for a two-species collisionless magnetoplasma in a form permitting direct comparison between them, have been applied to the study of the Alfvén modes in both low- and high-β plasmas. In the low-βregime all methods give essentially the same solutions for the isotropic fast magnetosonic and the field-guided shear Alfvén modes. The real part of the refractive index of the field-guided slow magnetosonic acoustic mode is almost identical in the fluid and kinetic analyses, but is 50% too high in the MHD analysis owing to neglect of the trace-free part of the pressure tensor which drives almost half of the acoustic energy flux. The strong damping of the acoustic mode in both low- and high-β plasmas is drastically reduced by increase of electron temperature, whereas a moderate increase in the perpendicular ion temperature is sufficient to eliminate shear Alfvén damping in high-β plasmas and even to produce wave growth, the effect being more pronounced the higher the plasma β. The fluid analysis shows the electromagnetic energy flux to be negligible in the acoustic mode, in which the acoustic flux is driven both by the trace-carrying and trace-free parts of the pressure tensor, but is usually the dominant component in the (fast) magnetosonic mode.
Lipase‐Mediated Purification of Methyl Nonactate, an Important Natural Product Building Block for Diversity‐Oriented Synthesis
Authors: Dinges Jennifer M. , Bessette Bradley A. , Cox James E. , Redder Casey R. , Priestley Nigel D. 
Published: August 2006

AbstractMethyl nonactate is a valuable starting material for the production of natural product‐like combinatorial libraries and ketide amino acids, a series of novel conformationally constrained amino acid analogues. Fermentation of Streptomyces griseus generates high titers of macrotetrolide antibiotics from which methyl nonactate can be generated by methanolysis. Unfortunately, this approach generates mixtures of homologues that are not economically separable. We report a specific lipase‐mediated hydrolysis of nonactate derivatives that discriminates between homologues and is the foundation of an economically tractable preparation of methyl nonactate in scale.
High affinity of sigma1‐binding sites for sterol isomerization inhibitors: evidence for a pharmacological relationship with the yeast sterol C8–C7 isomerase
Authors: Moebius Fabian F , Reiter Raphael J , Hanner Markus , Glossmann Hartmut 
Published: August 2006

The sigma‐drug binding site of guinea‐pig liver is carried by a protein which shares significant amino acid sequence similarities with the yeast sterol C8–C7 isomerase (ERG2 protein). Pharmacologically ‐ but not structurally ‐ the sigma1‐site is also related to the emopamil binding protein, the mammalian sterol C8–C7 isomerase. We therefore investigated if sterol C8–C7 isomerase inhibitors are high affinity ligands for the (+)‐[3H]‐pentazocine labelled sigma1‐binding site.
Among the compounds which bound with high affinity to native hepatic and cerebral as well as to yeast expressed sigma1‐binding sites were the agricultural fungicide fenpropimorph (Ki 0.005 nM), the antihypocholesterinaemic drugs triparanol (Ki 7.0 nM), AY‐9944 (Ki 0.46 nM) and MDL28,815 (Ki 0.16 nM), the enantiomers of the ovulation inducer clomiphene (Ki 5.5 and 12 nM, respectively) and the antioestrogene tamoxifen (Ki 26 nM).
Except for tamoxifen these affinities are essentially identical with those for the [3H]‐ifenprodil labelled sterol C8–C7 isomerase of S. cerevisiae. This demonstrates that sigma1‐binding protein and yeast isomerase are not only structurally but also pharmacologically related. Because of its affiliations with yeast and mammalian sterol isomerases we propose that the sigma1‐binding site is localized on a sterol isomerase related protein, involved in postsqualene sterol biosynthesis.

British Journal of Pharmacology (1997) 121, 1–6; doi:10.1038/sj.bjp.0701079
Tachykinin regulation of basal synovial blood flow
Authors: Ferrell W R , Lockhart J C , Karimian S M 
Published: August 2006

Experiments were performed to investigate the role of endogenously released tachykinins in the regulation of blood flow to the rat knee joint. Synovial perfusion was assessed by laser Doppler perfusion imaging, which permitted spatial measurement of relative changes in perfusion from control (pre drug administration), expressed as the percentage change. Most experiments were performed on the exposed medial aspect of the knee joint capsule.
Neither the selective tachykinin NK1 receptor antagonist, FK888, nor the selective tachykinin NK2 receptor antagonist, SR48968, significantly influenced synovial blood flow at doses of 10−12, 10−10 and 10−8 mol. However, topical co‐administration of these agents produced significant dose‐dependent reductions in basal synovial perfusion of 6.3±4.6, 12.0±3.4 and 19.9±2.6%, respectively; n=29. The non‐selective tachykinin NK1/NK2 receptor antagonist, FK224, also produced significant (at 10−10 and 10−8 mol), but less potent, reductions in perfusion of 5.3±4.0, 8.4±2.2 and 5.9±2.8%, respectively; n=25.
Topical administration of the α1‐, α2‐adrenoceptor antagonist phenoxybenzamine elicited a 31.3±6.2% increase in blood flow which was substantially reduced to 10.4±3.8% by co‐administration of the FK888 and SR48968 (both at 10−8 mol; n=8–13), suggesting that normally there is sympathetic vasoconstrictor ‘tone’ which is opposed by the vasodilator action of endogenous tachykinins.
One week after surgical interruption of the nerve supply to the knee joint, co‐administration of FK888 and SR48968 (both at 10−8 mol) now produced slight vasodilatation (6.7±4.6%; n=9) which did not differ significantly from vehicle treatment. Depletion of tachykinins from sensory nerve fibres by systemic capsaicin administration also resulted in abolition of the vasoconstrictor effect of FK888 and SR48968 (both at 10−8 mol), with these agents only producing a slight vasodilatation (2.5±5.3%; n=6).
By use of a near infra‐red laser source it was possible to image knee joint perfusion transcutaneously, the overlying skin being left intact. In this more physiological situation, close intra‐arterial injection of the combination of FK888 and SR48968 (both at 10−8 mol) again elicited vasoconstriction (48.8±16.2% reduction in blood flow; n=4).
These results indicate that endogenous tachykinins may be continuously released from sensory fibres innervating the joint. Basal release of tachykinins could therefore be an important physiological influence opposing sympathetic vasoconstrictor tone.

British Journal of Pharmacology (1997) 121, 29–34; doi:10.1038/sj.bjp.0701095