bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intact surface of bioactive glass S53P4 is resistant to osteoclastic activity
Authors: Wilson Timothy , Parikka Vilhelmiina , Holmbom Johanna , Ylänen Heimo , Penttinen Risto 
Published: December 2005

AbstractBioactive glass reacts with body fluids and is gradually dissolved in tissues and in cell cultures. We investigated whether osteoclasts contribute to this process, by culturing newborn rat bone‐marrow cells containing osteoclasts on polished bioactive glass plates (glass S53P4). The cultures were inspected at days 1–5 and stained for alkaline phosphatase (ALP) to demonstrate osteoblasts and for tartrate resistant acid phosphatase (TRAP) to visualize osteoclasts. Nonosteoclastic cells proliferated several‐fold both on bioactive glass and on plastic, whereas osteoclasts and their precursors matured into multicellular giant cells and degenerated. Most cells on bioactive glass became ALP‐positive, whereas on plastic the majority of cells remained ALP‐negative. Osteoclasts survived on bioactive glass for 4–5 days, whereas on plastic they degenerated and disappeared after 3 days. Condensed nuclei indicating apoptosis were detected both in degenerating osteoclasts and osteoblasts. The surface of the bioactive glass reacted rapidly forming rounded pits, erosions, and cracks within 24 h in areas occupied by osteoblasts. Light microscopy and scanning electron micrographs demonstrated, however, a smooth surface below the cytoplasm of osteoclasts. This indicates that when applied on an intact bioactive glass surface, osteoclasts were unable to dissolve the glass material within this culture period. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Mechanism of in vivo DNA transport into cells by electroporation: electrophoresis across the plasma membrane may not be involved
Authors: Liu Feng , Heston Steve , Shollenberger Lisa M , Sun Bin , Mickle Marlin , Lovell Michael , Huang Leaf 
Published: December 2005

AbstractBackgroundRecently, in vivo gene transfer with electroporation (electro‐gene transfer) has emerged as a leading technology for developing nonviral gene therapies and nucleic acid vaccines. The widely hypothesized mechanism is that electroporation induces structural defects in the membrane and provides an electrophoretic force to facilitate DNA crossing the permeabilized membrane. In this study, we have designed a device and experiments to test the hypothesis.MethodsIn this study, we have designed a device that alternates the polarity of the applied electric field to elucidate the mechanism of in vivo electro‐gene transfer. We also designed experiments to challenge the theory that the low‐voltage (LV) pulses cannot permeabilize the membrane and are only involved in DNA electrophoresis, and answer the arguments that (1) the reversed polarity pulses can cause opposing sides of the cell membrane to become permeabilized and provide the electrophoresis for DNA entry; or (2) once DNA enters cytoplasmic/endosomal compartments after electroporation, it may bind to cellular entities and might not be reversibly extracted. Thus a gradual buildup of the DNA in the cell still seems quite possible even under the condition of the rapid reversal of polarity.ResultsOur results indicate that electrophoresis does not play an important role in in vivo electro‐gene transfer.ConclusionsThis study provides new insights into the mechanism of electro‐gene transfer, and may allow the definition of newer and more efficient conditions for in vivo electroporation. Copyright © 2005 John Wiley & Sons, Ltd.
Studies on thermionic ionisation detection in comprehensive two‐dimensional gas chromatography
Authors: Ryan Danielle , Marriott Philip 
Published: December 2005

AbstractThis study explores the application of specific thermionic ionisation detection in comprehensive 2‐D GC (GC×GC) and represents the first report of GC×GC with nitrogen phosphorus detection (GC×GC‐NPD). Of particular interest is the performance of the NPD with respect to peak parameters of asymmetry and sensitivity. Since GC×GC produces much narrower peaks than obtained with fast GC (e. g. 100 ms vs. < 1 s) the effect of detector response time and any lack of symmetry arising from the detection step is important if peak separation (resolution) is to be maintained. It was observed that detector gas flows had a significant impact on peak asymmetry and peak magnitude, and that optimisation of the detector was critical, particularly for complex sample analysis by GC×GC‐NPD. Peak asymmetries ranging from As = 1.8 to 8.0 were observed under different conditions of detector gas flows. Comparison of GC×GC‐NPD with GC×GC‐flame ionisation detection (FID) showed the former to be approximately 20 times more sensitive for the detection of nitrogen‐containing methoxypyrazines analytes, and GC×GC‐NPD had a larger linear detection range compared to GC×GC‐FID. Furthermore, comparison of GC×GC‐NPD and GC×GC‐TOFMS chromatograms for the analysis of coffee headspace demonstrated the benefits of selective detection, ultimately realised in a comparatively simplified contour plot.
On‐line redox derivatization liquid chromatography using double separation columns and one derivatization unit
Authors: Saitoh Kazunori , Yamada Noriko , Ishikawa Eri , Nakajima Hizuru , Shibukawa Masami 
Published: December 2005

AbstractA new on‐line redox derivatization technique using double separation columns and one redox derivatization unit was presented for enhancement of separation selectivity of HPLC. This on‐line redox derivatization HPLC system consisted of two separation columns and one redox derivatization unit placed between them. The redox reaction proceeds in the derivatization unit so that an analyte compound migrates as its original form in the first column, while as its oxidized or reduced form in the second column. The retention of the analytes is controlled by the lengths of the two separation columns in this system. We adopted a small column packed with porous graphitic carbon (PGC) as a redox derivatization unit and two C18 silica columns treated with hexadecyltrimethylammonium chloride as separation columns. The redox activity of PGC and the efficiency of the on‐line redox derivatization HPLC system for enhancement of separation selectivity were investigated using EDTA complexes of some metal ions. Original untreated PGC and PGC treated with hydrogen peroxide completely oxidized Co(II)‐EDTA and converted it to Co(III)‐EDTA, while the other metal complexes eluted as their original oxidation states throughout the system. Selective separation and determination of cobalt in a reference copper alloy by the developed method were demonstrated.
Polymer‐based monolithic microcolumns for hydrophobic interaction chromatography of proteins
Authors: Hemström Petrus , Nordborg Anna , Irgum Knut , Svec Frantisek , Fréchet Jean M. J. 
Published: December 2005

AbstractMonolithic capillary columns for hydrophobic interaction chromatography (HIC) have been prepared by thermally initiated, single‐step in situ polymerization of mixtures of monovinyl monomers including butyl methacrylate and/or 2‐hydroxyethyl methacrylate, with a divinyl crosslinker glycerol dimethacrylate or 1,4‐butanediol dimethacrylate using two different porogen systems. Two porogenic solvent mixtures were used; one “hydrophilic”, consisting of water, butanediol, and propanol, and one “hydrophobic,” comprising dodecanol and cyclohexanol. The porous structures of the monoliths were characterized and their performance was demonstrated with a separation of a mixture of myoglobin, ribonuclease A, and lysozyme under conditions typical of HIC.
Capillary electrophoretic separation of inorganic sulfur–sulfide, polysulfides, and sulfur‐oxygen species
Authors: Petre Catalin Florin , Larachi Faïçal 
Published: December 2005

AbstractA CE protocol was developed for the identification and separation of inorganic polysulfides simultaneously with other inorganic sulfur‐bearing species coexisting in aqueous hydrosulfide/sulfur solutions. The electrophoretic separation of thiosulfate, sulfate, hydrosulfide, sulfite, tetrathionate, and polysulfides was achieved at pH values between 8.2 and 12.2. The peaks attributed to the polysulfide species were strongly sensitive to pH. CE analysis of hydrosulfide/sulfur solutions at different pH values permitted possible identification of two forms of polysulfides: S42– and S32–. Upon exposure to air at ambient temperature, thiosulfate was the main oxidation product of hydrosulfide/sulfur solutions mainly in the first 60 min, when hydrosulfide was rapidly consumed. Analysis of the oxidation reaction products provided retrospectively tentative evidence that the peaks separated and identified as tri‐ and tetrasulfide may be ascribed to polysulfides.
Preparation and properties of isobutylene–isoprene rubber–clay nanocomposites
Authors: Kato Makoto , Tsukigase Azusa , Tanaka Hiromitsu , Usuki Arimitsu , Inai Isamu 
Published: December 2005

AbstractIsobutylene isoprene rubber (IIR)‐clay nanocomposites have been prepared successfully by melt intercalation with maleic anhydride‐grafted IIR (Ma‐g‐IIR) and organophilic clay. In IIR‐clay nanocomposites, the silicate layers of the clay were exfoliated and dispersed into the monolayer. The nanocomposites exhibited greater gas barrier properties compared with those of Ma‐g‐IIR. When 15 phr clay was added, gas barrier properties were 2.5 times greater than those of Ma‐g‐IIR. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1182–1188, 2006
Rasch analysis of the dimensional structure of the Hospital Anxiety and Depression Scale
Authors: Smith A.B. , Wright E.P. , Rush R. , Stark D.P. , Velikova G. , Selby P.J. 
Published: December 2005

AbstractThe Hospital Anxiety and Depression Scale (HADS) has been used extensively in cancer patients to identify psychological distress. Reports of the factor structure and screening performance of the instrument vary. Rasch models allow an assessment of the structure of a questionnaire by identifying item fit. Removal of misfitting items may improve both the dimensionality and efficacy of screening questionnaires.A Rasch analysis of the HADS‐T and subscales was used to explore the factor structure, dimensionality and screening efficacy. A total of 1855 patients completed a touchscreen version of the HADS, including 381 patients who had received a psychiatric interview (SCAN/PSE). These data were analysed using Rasch models, and the screening efficacy at identifying cases of psychological distress and anxiety and depression evaluated.The results demonstrated that the structure of the HADS‐T and subscales was unidimensional. Three items from the HADS‐T, and one from each of the subscales demonstrated misfit. Screening efficacy for the HADS‐T and subscales was modest. However, removal of misfitting items had little impact on screening, demonstrating that items could potentially be omitted, if required. The item range covered a narrow spectrum of psychological distress, predominantly higher levels of distress. Additional items have to be added if screening for moderate to mild distress is to be improved for cancer patients. Copyright © 2005 John Wiley & Sons, Ltd.
Gene therapy for prostate cancer: Current strategies and new cell‐based approaches
Authors: MacRae E.J. , Giannoudis A. , Ryan R. , Brown N.J. , Hamdy F.C. , Maitland N. , Lewis C.E. 
Published: December 2005

AbstractProstate cancer is the most commonly diagnosed cancer in adult males in the Western world. It accounts for one in ten cancer cases and is the second leading cause of cancer death in men, after lung cancer. A number of curative treatments are available for patients with localized prostate cancer such as radical prostatectomy, radiotherapy, or brachytherapy. However, a proportion of these men will develop progressive disease, and some will present de novo with advanced and metastatic prostate cancer, which is amenable to palliation only with androgen‐withdrawal therapy. Most of these patients will eventually develop hormone refractory disease which is incurable, and for whom gene therapy, if feasible may develop as an alternative treatment option. In this review we discuss the gene therapy vectors and strategies that are currently in use, new cell‐based approaches, discuss their advantages and disadvantages, and review the potential or proven pre‐clinical and clinical efficacy in prostate cancer models/patients. © 2005 Wiley‐Liss, Inc.
Directed evolution of the epidermal growth factor receptor extracellular domain for expression in yeast
Authors: Kim Yong‐Sung , Bhandari Rashna , Cochran Jennifer R. , Kuriyan John , Wittrup K. Dane 
Published: December 2005

AbstractThe extracellular domain of epidermal growth factor receptor (EGFR‐ECD) has been engineered through directed evolution and yeast surface display using conformationally‐specific monoclonal antibodies (mAbs) as screening probes for proper folding and functional expression in Saccharomyces cerevisiae. An EGFR mutant with four amino acid changes exhibited binding to the conformationally‐specific mAbs and human epidermal growth factor, and showed increased soluble secretion efficiency compared with wild‐type EGFR. Full‐length EGFR containing the mutant EGFR‐ECD was functional, as assayed by EGF‐dependent autophosphorylation and intracellular MAPK signaling in mammalian cells, and was expressed and localized at the plasma membrane in yeast. This approach should enable engineering of other complex mammalian receptor glycoproteins in yeast for genetic, structural, and biophysical studies. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Solvent participation in Serratia marcescens endonuclease complexes
Authors: Chen Chuanying , Beck Brian W. , Krause Kurt , Pettitt B. Montgomery 
Published: December 2005

AbstractThe monomer and dimer of the bacterium Serratia marcescens endonuclease (SMnase) are each catalytically active and the two subunits of the dimer function independently of each other. Specific interfacial waters may play a role in stability, complex formation, and functionality. We performed molecular dynamics simulations of both a subunit of SMnase and its model built complex with DNA and analyzed the relation of the hydration sites to the catalytic mechanism. It was found that the binding of DNA has little influence on the global hydration properties of the protein, including occupancy and water residence time distributions. DNA and protein recognition in our model mainly involves direct contacts by hydrogen bond and hydrophobic interactions. Water‐mediated contacts exist, but are less common. Three interior water clusters were identified for SMnase. One cluster around the active site in the monomer–DNA complex shows relatively strong interactions between hydration sites as well as between the sites and the biomolecules. The simulated cluster properties agreed well with experimental data. The magnesium ion shows ligand exchange. Although Mg2+ keeps six ligands during the entire simulation, upon the binding of DNA, Asn119 loses its coordination with Mg2+, while one nonbridging oxygen of the phosphate of a DNA residue and two oxygen atoms of the side chain of Glu127 become the ligands. Waters in a nearby cluster exchange and participate in the resolvation of groups in the presence of DNA. Water thus not only participates in the cleavage of DNA but also can stabilize the transition state and the leaving groups in our model. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Conversion of type I 4:6 to 3:5 β‐turn types in human acidic fibroblast growth factor: Effects upon structure, stability, folding, and mitogenic function
Authors: Lee Jihun , Dubey Vikash Kumar , Somasundaram Thayumanasamy , Blaber Michael 
Published: December 2005

AbstractHuman acidic fibroblast growth factor (FGF‐1) is a member of the β‐trefoil superfold, a protein architecture that exhibits a characteristic threefold axis of structural symmetry. FGF‐1 contains 11 β‐turns, the majority being type I 3:5; however, a type I 4:6 turn is also found at three symmetry‐related locations. The relative uniqueness of the type I 4:6 turn in the FGF‐1 structure suggests it may play a key role in the stability, folding, or function of the protein. To test this hypothesis a series of deletion mutations were constructed, the aim of which was to convert existing type I 4:6 turns at two locations into type I 3:5 turns. The results show it is possible to successfully substitute the type I 4:6 turn by a type I 3:5 turn with minimal impact upon protein stability or folding. Thus, these different turn structures, even though they differ in length, exhibit similar energetic properties. Additional sequence swapping mutations within the introduced type I 3:5 turns suggests that the turn sequence primarily affects stability but not turn structure (which appears dictated primarily by the local environment). Although the results suggest that a stable, foldable β‐trefoil protein may be designed utilizing a single turn type (type I 3:5), a type I 4:6 turn at turn 1 of FGF‐1 appears essential for efficient mitogenic function. Proteins 2006. © 2005 Wiley‐Liss, Inc.
BLEVE blast by expansion‐controlled evaporation
Authors: van den Berg A.C. , van der Voort M.M. , Weerheijm J. , Versloot N.H.A. 
Published: December 2005

AbstractThis report presents a new method to calculate the blast effects originating from an exploding vessel of liquefied gas. Adequate blast calculation requires full knowledge of the blast source characteristics, that is, the release and subsequent evaporation rate of the flashing liquid. Because the conditions that allow explosive evaporation are not entirely clear and the evaporation rate of a flashing liquid is unknown, safe assumptions have been adopted as the starting point in the modeling. The blast effects from a boiling liquid expanding vapor explosion (BLEVE) are numerically computed by imposing the vapor pressure of a flashing liquid as boundary condition for the gas dynamics of expansion. The numerical modeling is quantitatively explored just for liquefied propane. In addition, this paper demonstrates that often an estimate of BLEVE blast effects is possible with very simple acoustic volume source expressions.The modeling shows that the rupture of a pressure vessel containing a liquefied gas in free space develops a blast of significant strength only if the vessel nearly instantaneously disintegrates. Even if a rupture and the consequent release and evaporation of a liquefied gas extend over just a short period of time, the blast effects are minor. © 2005 American Institute of Chemical Engineers Process Saf Prog, 2006
Implementing inherently safer design in an existing plant
Authors: Hendershot Dennis C. , Sussman Jonathan A. , Winkler Gerald E. , Dill G. Lee 
Published: December 2005

AbstractAlthough the best time for implementation of inherently safer design alternatives is during early process development and plant design, there are often opportunities to modify an existing plant to significantly enhance inherent safety. We will describe a modification to a bromine raw material handling facility, replacing an existing bulk storage tank with cylinders. Incident consequence analysis and quantitative risk analysis were used to understand the relative inherent safety characteristics of the design options. © 2005 American Institute of Chemical Engineers Process Saf Prog, 2006
Tribological characterisation of hard coatings with and without DLC top layer in fretting tests
Authors: Klaffke D. 
Published: December 2005

AbstractThe potential of coatings to protect components against wear and to reduce friction has led to a large variety of protective coatings. In order to check the success of coating modifications and to find solutions for different purposes, initial tests with laboratory tribometers are usually done to give information about the performance of a coating.Different Ti‐based coatings (TiN, Ti(C,N), and TiAlN) and NiP were tested in comparison to coatings with an additional diamond‐like carbon (DLC) top coating. Tests were done in laboratory air at room temperature with oscillating sliding (gross slip fretting) with a ball‐on‐disc arrangement against a ceramic ball (Al2O3). Special attention was paid to possible effects of moisture (relative humidity). The coefficient of friction was measured on line, and the volumetric wear at the disc was determined after the test from microscopic measurements of the wear scar and additional profiles.The friction and wear behaviour is quite different for the different coatings and depends more or less on the relative humidity. The DLC coating on top of the other coatings reduces friction and wear considerably. In normal and in moist air the coefficient of wear of the DLC top‐layer coating is significantly less than 10−6 mm3/Nm and the coefficient of friction is below 0.1. In dry air, however, there is a certain tendency to high wear and high friction. Copyright © 2006 John Wiley & Sons, Ltd.
Experimental device for the observation of rubbing surfaces during braking tests
Authors: François M. , Bulthé A.L. , Desplanques Y. , Degallaix G. 
Published: December 2005

AbstractThis paper introduces an experimental device, developed at the Laboratoire de Mécanique de Lille, specially designed for application in braking tests. The purpose of this device is to monitor the course of events on the rubbing surfaces during simulated braked stops and, in particular, the life and the dynamics of the third body. The usefulness of the device is demonstrated by the results of braking experiments performed on a grey cast iron disc for two different energies. These first experimental results show that the technique provides efficient and exploitable observations of tribological phenomena occurring on the wear‐track scale as well as on the microscopic scale. Copyright © 2006 John Wile & Sons, Ltd.
Acute haemorrhage in patients with advanced head and neck cancer: value of endovascular therapy as palliative treatment option
Authors: Sesterhenn Andreas M , Iwinska-Zelder Joanna , Dalchow Carsten V , Bien Siegfried , Werner Jochen A 
Published: December 2005

Aims: Acute or subacute haemorrhage is one of the most frightening complications in patients suffering from advanced head and neck cancer. Few articles report experience with superselective endovascular therapy for this purpose. Is endovascular therapy underestimated in the field of palliative head and neck cancer therapy? This study set out to investigate this question.Patients and methods: A review was undertaken of the clinical courses of seven patients (six men, one woman) suffering from incurable, advanced head and neck cancer (four pharyngeal, two laryngeal, one neck) and treated with superselective endovascular strategies as an emergency procedure for acute bleeding.Results: All patients were successfully treated without evidence of neurological complication. Patients reached a median survival of 20 weeks (range eight–168 weeks). Following endovascular treatment all patients were discharged from the hospital within several days. Three patients survived almost free of symptoms for several weeks and were able to stay at home with their families until their death.Conclusion: We conclude that in the field of palliative care, superselective endovascular therapy deserves to be considered alongside standard treatment options for the management of acute haemorrhage from advanced head and neck cancer.