bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrating Regional and Community Lung Cancer Services to Improve Patient Care
Authors: Dahele M. , Ung Yee , Meharchand J. , Shulman H. , Zeldin R. , Behzadi A. , Simone C. , Cheng S. , Weigensberg C. , Sivjee K.
Published: December 2007

Lung cancer is the leading cause of cancer death in Canada. The organization of health care services is central to the delivery of accessible, high-quality medical care and may be one factor that influences patient outcome. An exciting opportunity arose for clinicians to initiate the redesign of lung cancer services provided by three institutions in the Greater Toronto Area. This qualitative report describes the integrated lung cancer network that they developed, the innovation it has facilitated, and the systematic approach being taken to evaluate its impact. Available clinical resources were deployed to restructure services along patient-centred lines and to provide greater access to the specialist lung cancer team. A non-hierarchical clinical network was established that consolidates the lung cancer team. A multi-institutional and multidisciplinary tumour board and comprehensive thoracic oncology clinics are at its core. This innovative organizational paradigm considers all of the available services at each facility and aims to fully integrate specialists across the three institutions, thereby maximizing resource utilization. We believe that this paradigm may have wider applicability. The network is currently working to complete a current program of further service improvements and to objectively assess its impact on patient outcome.
Microstructures of CGO and YSZ Thin Films by Pulsed Laser Deposition
Authors: Infortuna A. , Harvey A. S. , Gauckler L. J.
Published: December 2007

Yttrium‐stabilized zirconia (YSZ) and cerium gadolinium oxide (CGO) thin films were prepared by pulsed laser deposition (PLD) under different ambient pressures and substrate temperatures. The microstructures of the obtained films are compared with existing structural zone models for thin‐film growth. The model developed by Thornton (1974) for metallic sputtered films is applied to the metal oxide films grown by PLD and gives a good description for the growth process and the dependence of the microstructure on deposition temperature and pressure. A map of formed microstructures is compiled as a function of background pressure and substrate temperature, and the conditions to obtain dense or porous films for YSZ and CGO are established. The two materials show the same dependence on temperature and pressure. Higher background pressure yields more porous films and a fully dense structure cannot be achieved for substrate temperatures in the range from room temperature to 800 °C. Of special interest for us was the realization and characterization of dense films processed at low temperature (< 500 °C) for the preparation of free‐standing membranes to be used in a micro solid oxide fuel cell. We could achieve such films by processing at 400 °C in 0.026 mbar of oxygen. In‐plane electric conductivities of the films were measured and correlated with the microstructures.
New case of interstitial deletion 12(q15‐q21.2) in a girl with facial dysmorphism and mental retardation
Authors: Schluth Caroline , Gesny Roselyne , Borck Guntram , Redon Richard , Abadie Véronique , Kleinfinger Pascale , Munnich Arnold , Lyonnet Stanislas , Colleaux Laurence
Published: December 2007

Interstitial deletions of the long arm of chromosome 12 are rare rearrangements with only 15 cases reported in the literature. The phenotype may include facial dysmorphism, developmental delay, ectodermal abnormalities, cardiac and renal malformations depending on breakpoints' position. Here, we describe a third case of 12(q15‐q21.2) deletion ascertained through CGH‐array analyses and provide a 5‐year follow‐up. The patient presented with pre‐ and postnatal growth retardation, congenital heart defect, developmental delay, and facial dysmorphism changing with age, underlining the importance of long‐term follow‐up. We compared this new case with previous observations of 12q deletions in order to propose phenotype–karyotype correlations. © 2007 Wiley‐Liss, Inc.
Pseudoarthrosis of the clavicle and copper beaten skull associated with chromosome 10p11.21p12.1 microdeletion
Authors: Shahdadpuri Raveen , de Vries Bert , Pfundt Rolph , de Leeuw Nicole , Reardon William
Published: December 2007

Congenital pseudoarthrosis of the clavicle (CPC) has been described in several genetic conditions including Floating–Harbor and Goltz syndromes, but rarely as a prompt to specific cytogenetic abnormalities. We report on a case of a de novo 10p11.21p12.1 microdeletion in a boy with multiple problems including a beaten copper appearance of the cranium on skull X‐ray and pseudoarthrosis of the right clavicle. This is the first description of these particular skeletal findings in the context of a chromosome 10p deletion. © 2007 Wiley‐Liss, Inc.
Population genetic studies ofAlouatta belzebulfrom the Amazonian and Atlantic Forests
Authors: Nascimento F.F. , Bonvicino C.R. , de Oliveira M.M. , Schneider M.P.C. , Seuánez Héctor N.
Published: December 2007

CytochromebDNA sequence data (ca. 1,140 bp) of 66Alouatta belzebulfrom the Amazonian and the Atlantic Forests of Brazil were used for phylogenetic reconstructions and population studies. Our sample consisted of 60 specimens from the Amazonian Forest (captured in 1984 and 1998 in Pará‐PA state) and six specimens from the Atlantic Forest (Paraíba‐PB state). We found 32 haplotypes, 23 in PA‐1984 (with 12 present in more than one individual), 11 in PA‐1998 (with two present in more than one individual), and a single haplotype in the PB sample. Animals from PA‐1984 and PA‐1998 shared three haplotypes while animals from Pará and Paraíba did not share any haplotype. We found 57 variable sites, consisting of 53 transitions and four transversions, with most replacements occurring at third codon position (77.19%) and less frequently at first and second positions (10.53 and 12.28%, respectively). Genetic distance between all haplotypes varied between 0 and 1.2%. Nucleotide diversity estimates between PA‐1984 haplotypes and PA‐1998 haplotypes were the same (π=0.01), and haplotype diversity estimates were very similar (h=0.96 and 0.93 for PA‐1984 and PA‐1998, respectively). Maximum parsimony, median‐joining, split decomposition, and TCS showed that PA and PB haplotypes had not drastically diverged and that subsequent radiation within these regions was not apparent. No temporal structure was found between PA‐1984 and PA‐1998. The sum of square deviation estimate for PA‐1984 equaled 0.01 (P=0.23), in agreement with a hypothetical model of sudden expansion contrary to PA‐1998 whose sum of square deviation estimate (0.40;P=0.04) was not compatible with this model, although the small sample size of PA‐1998 as well as the smaller area of capture could have also accounted for this result. Fu's FsandR2statistical neutrality tests corroborated these propositions. Lack of drastic differentiation was attributable to the once existing connection between the Atlantic and the Amazonian forests at a non‐distant past. Am. J. Primatol. 70:423–431, 2008. © 2007 Wiley‐Liss, Inc.
Stille cross‐coupling reaction using Pd/BaSO4 as catalyst reservoir
Authors: Coelho Aline Viana , de Souza Andréa Luzia F. , de Lima Paulo G. , Wardell James L. , Antunes O. A. C.
Published: December 2007

Stille cross‐coupling reactions between iodobenzene and tributylphenyltin were carried out in ethanol/water solution using different amounts of Pd/BaSO4 as catalyst reservoir in a ligand‐free system and high yields were obtained. Other substituted biaryls were obtained with good yields. The catalyst can be reused up to three times with some loss in activity. Filtration of the catalyst and product extraction yielded a solution that kept its activity, showing the presence of Pd(0)/Pd(II) species that can be regarded as the true catalysts. Interestingly, both 2‐bromotiophene and chlorobenzene yielded the desired corresponding reaction products. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of additives on the composition dependent glass transition variation in PS/PP blends
Authors: Thirtha Vivek , Lehman Richard , Nosker Thomas
Published: December 2007

The effect of additives on glass transition behavior in melt processed blends of polystyrene (PS) and polypropylene (PP) was studied. Blends of additive‐free polystyrene and additive‐free polypropylene revealed the known effect of the PS Tg increase in blend compositions where PP surrounds PS. Glass transition behavior in these blends was compared to blends prepared from additive‐free PP and commercial grade PS, which contained lubricant additives. The thermal transitions of PS and PP were measured using modulated DSC. Although the behavior of low PS concentration blends was similar in both systems, the characteristics of the high PS blends differed substantially. These differences and the contrast in the PP Tg behaviors were attributed to the migration of additives from the PS phase across the immiscible interface into the PP phase. Similar Tg variations were observed in blends of commercial grade PS and commercial grade PP. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Thin layer concentrated emulsion copolymerization of PUASi/Styrene/Methyl methacrylate
Authors: Zhang Hongtao , Chen Li , Duan Lingli , Huang He
Published: December 2007

Stable concentrated emulsions of polymerizable polysiloxane‐containing polyurethane (PUASi)/Styrene (St)/Methyl methacrylate (MMA) were prepared using sodium dodecyl sulphate (SDS)/nonyl polyoxyethylene ether (OS15)/polyvinyl alcohol (PVA) as composite surfactant and azobisisobutyronitrile (AIBN) as initiator. A novel polymerization method, thin layer polymerization was used to carry out the concentrated emulsion copolymerization at 55°C. The effects of TDI/PPG molar ratio, surfactant concentration, different kinds of surfactants, and temperature on polymerization stability were studied. The effects of the thickness of the thin layer, the outside temperature of the reactor, as well as polymerization environment on the volatilization rate of water, and monomer in the system were investigated. The conversion‐time relationships of the thin layer polymerization and the tube polymerization, as well as the effect of polymerization environment on the polymerization rate were also investigated. The morphology of latex particles was determined with transmission electron microscope (TEM). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Development of nanofibrous morphology in LDPE/LLDPE/PP blends and its effect on mechanical properties of blend films
Authors: Sonawane Pradip S. , Radhakrishnan S. , Bhangale J. A. , Gadhavi A. L. , Khare Anagha
Published: December 2007

Nanofibrous morphology has been observed in ternary blends of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and isotactic polypropylene (PP) when these were melt‐extruded via slit die followed by hot stretching. The morphology was dependent on the concentration of the component polymers in ternary blend LDPE/LLDPE/PP. The films were characterized by wide angle X‐ray diffraction (XRD), scanning electron microscopy (SEM), and testing of mechanical properties. The XRD patterns reveal that the β phase of PP is obtained in the as‐stretched nanofibrillar composites, whose concentration decreases with the increase of LLDPE concentration. The presence of PP nanofibrils shows significant nucleation ability for crystallization of LDPE/LLDPE blend. The SEM observations of etched samples show an isotropic blend of LDPE and LLDPE reinforced with more or less randomly distributed and well‐defined nanofibrils of PP, which were generated in situ. The tensile modulus and strength of LDPE/LLDPE/PP blends were significantly enhanced in the machine direction than in the transverse direction with increasing LLDPE concentration. The ultimate elongation increased with increasing LLDPE concentration, and there was a critical LLDPE concentration above which it increased considerably. There was a dramatic increase in the falling dart impact strength for films obtained by blow extrusion of these blends. These impressive mechanical properties of extruded samples can be explained on the basis of the formation of PP nanofibrils with high aspect ratio (at least 10), which imparted reinforcement to the LDPE/LLDPE blend. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Monodisperse Magnetite Nanoparticles Coupled with Nuclear Localization Signal Peptide for Cell‐Nucleus Targeting
Authors: Xu Chenjie , Xie Jin , Kohler Nathan , Walsh Edward G. , Chin Y. Eugene , Sun Shouheng
Published: December 2007

Functionalization of monodisperse superparamagnetic magnetite (Fe3O4) nanoparticles for cell specific targeting is crucial for cancer diagnostics and therapeutics. Targeted magnetic nanoparticles can be used to enhance the tissue contrast in magnetic resonance imaging (MRI), to improve the efficiency in anticancer drug delivery, and to eliminate tumor cells by magnetic fluid hyperthermia. Herein we report the nucleus‐targeting Fe3O4 nanoparticles functionalized with protein and nuclear localization signal (NLS) peptide. These NLS‐coated nanoparticles were introduced into the HeLa cell cytoplasm and nucleus, where the particles were monodispersed and non‐aggregated. The success of labeling was examined and identified by fluorescence microscopy and MRI. The work demonstrates that monodisperse magnetic nanoparticles can be readily functionalized and stabilized for potential diagnostic and therapeutic applications.
GDNF fusion protein for targeted‐drug delivery across the human blood–brain barrier
Authors: Boado Ruben J. , Zhang Yun , Zhang Yufeng , Wang Yuntao , Pardridge William M.
Published: December 2007

Glial‐derived neurotrophic factor (GDNF) is a neurotrophin that could be developed as a neurotherapeutic for Parkinson's disease, stroke, and motor neuron disease. However, GDNF does not cross the blood–brain barrier (BBB). Human GDNF was re‐engineered by fusion of the mature GDNF protein to the carboxyl terminus of the chimeric monoclonal antibody (MAb) to the human insulin receptor (HIR). The HIRMAb‐GDNF fusion protein is bi‐functional, and both binds the HIR, to trigger receptor‐mediated transport across the BBB, and binds the GDNF receptor (GFR)‐α1, to activate GDNF neuroprotection pathways behind the BBB. COS cells were dual transfected with the heavy chain (HC) and light chain fusion protein expression plasmids, and the HC of the fusion protein was immunoreactive with antibodies to both human IgG and GDNF. The HIRMAb‐GDNF fusion protein bound with high affinity to the extracellular domain of both the HIR, ED50 = 0.87 ± 0.13 nM, and the GFRα1, ED50 = 1.68 ± 0.17 nM. The HIRMAb‐GDNF fusion protein activated luciferase gene expression in human neural SK‐N‐MC cells dual transfected with the c‐ret kinase and a luciferase reporter gene under the influence of the rat tyrosine hydroxylase promoter, and the ED50, 1.68 ± 0.45 nM, was identical to the ED50 in the GFRα1 binding assay. The fusion protein was active in vivo in a rat middle cerebral artery occlusion model, where the stroke volume was reduced 77% (P < 0.001). In conclusion, these studies describe the re‐engineering of GDNF, to make this neurotrophin transportable across the human BBB. Biotechnol. Bioeng. 2008;100: 387–396. © 2007 Wiley Periodicals, Inc.
Predicting first molar width using virtual models of dental arches
Authors: Lee Seung‐Pyo , Delong Ralph , Hodges James S. , Hayashi Kazuo , Lee Jae‐Bong
Published: December 2007

In dentistry, large regions of dentition often are restored with minimal information about the original anatomy. The ability to predict missing anatomy from existing anatomy would aid such restorations. This study investigated the relationship between first molar mesial‐distal width and arch shape using newly defined reference points and three‐dimensional (3D) digital methods. Full‐mouth dental stone casts from 167 dental students were scanned and rendered as 3D virtual models. Maxillary and mandibular arch lengths and widths and first molar mesial‐distal widths were measured on the virtual models using new definitions incorporating virtual planes. A linear mixed model of the first molar width regressed on the other measurements was done. Intraobserver reproducibility was evaluated by means of intraclass correlation (ICC) and standard deviation of measurement error (SDME). All measured distances were averaged as a combined group and as gender groups. The correlation coefficients between the maxillary and mandibular first molar widths were over 0.70 (P < 0.01). Intraobserver error was small. ICCs were over 0.92 and SDMEs were from 0.11 to 0.21 mm. Arch dimensions and first molar widths were defined and measured. Regression equations were calculated for predicting first molar width. The prediction of first molar width using arch dimension is essential for virtual designing of missing first molars. This approach also provides reliable reference point definitions for the virtual dental model which was impossible with traditional measurement methods. Therefore, this study would be helpful for understanding the 3D anatomy of dental arch and fabrication of automatic prosthodontic restorations. Clin. Anat. 21:27–32, 2008. © 2007 Wiley‐Liss, Inc.
Synthesis, Molecular Structure and Properties of the [H6−nNi30C4(CO)34(CdCl)2]n− (n=3–6) Bimetallic Carbide Carbonyl Cluster: A Model for the Growth of Noncompact Interstitial Metal Carbides
Authors: Bernardi Alessandro , Femoni Cristina , Iapalucci Maria Carmela , Longoni Giuliano , Ranuzzi Fabrizio , Zacchini Stefano , Zanello Piero , Fedi Serena
Published: December 2007

Reaction of the [Ni9C(CO)17]2− dianion with CdCl2⋅2.5 H2O in THF affords the novel bimetallic NiCd carbide carbonyl clusters [H6−nNi30C4(CO)34(μ5‐CdCl)2]n− (n=3–6), which undergo several protonation–deprotonation equilibria in solution depending on the basicity of the solvent or upon addition of acids or bases. Although the occurrence in solution of these equilibria complicates the pertinent electrochemical studies on their electron‐transfer activity, they clearly indicate that the clusters [H6−nNi30C4(CO)34(μ5‐CdCl)2]n− (n=3–6), as well as the structurally related [H6−nNi34C4(CO)38]n− (n=4–6), undergo reversible or partially reversible redox processes and provide circumstantial and unambiguous evidence for the presence of hydrides for n=3, 4 and 5. Three of the [H6−nNi30C4(CO)34(μ5‐CdCl)2]n− anions (n=4–6) have been structurally characterized in their [NMe3(CH2Ph)]4[H2Ni30C4(CO)34(CdCl)2]⋅2 COMe2, [NEt4]5[HNi30C4(CO)34(CdCl)2]⋅2 MeCN and [NMe4]6[Ni30C4(CO)34(CdCl)2]⋅6 MeCN salts, respectively. All three anions display almost identical geometries and bonding parameters, probably because charge effects are minimized by delocalization over such a large metal carbonyl anion. Moreover, the Ni30C4 core in these NiCd carbide clusters is identical within experimental error to those present in the [HNi34C4(CO)38]5− and [Ni35C4(CO)39]6− species, suggesting that the stepwise assembly of their nickel carbide cores may represent a general pathway of growth of nickel polycarbide clusters. The fact that the [H6−nNi30C4(CO)34(μ5‐CdCl)2]n−(n=4–6) anions display two valence electrons more than the structurally related [H6−nNi34C4(CO)38]n− (n=4–6) species has been rationalized by extended Hückel molecular orbital (EHMO) analysis.
Modeling Carbon and Nitrogen Removal in an Industrial Wastewater Treatment Plant Using an Adaptive Network‐Based Fuzzy Inference System
Authors: Civelekoglu Gokhan , Perendeci Altunay , Yigit Nevzat O. , Kitis Mehmet
Published: December 2007

Advanced neuro‐fuzzy modeling, namely an adaptive network‐based fuzzy inference system (ANFIS), was employed to develop models for the prediction of carbon and nitrogen removal in the aerobic biological treatment stage of a full‐scale wastewater treatment plant treating process wastewaters from the sugar production industry. A total of six independent ANFIS models were developed with or without principal component analysis (PCA) using the correlations among the influent and effluent data from the plant. Input variables were reduced from eight to four and from eleven to nine for chemical oxygen demand (COD) and NH4+–N–TN (total nitrogen) models, respectively, by considering PCA results and linear correlation matrices among input and output variables. Correlation coefficients (R) were not in good agreement with root mean square error (RMSE) and average percentage error (APE) values without PCA. For the COD model after PCA; RMSE, APE and R values were 9.4 mg/L, 8.37 and 0.978%, respectively. Such values for the TN model were 4.3 mg/L, 23.65 and 0.992%. The results overall indicated that the simulated effluent COD, NH4+–N, and TN concentrations well fit measured concentrations. The ANFIS modeling approach may have application potential for performance prediction and control of treatment processes in treatment plants.
Model Based Evaluation for the Anaerobic Treatment of Corn Processing Wastewaters
Authors: Ersahin Mustafa Evren , Insel Guclu , Dereli Recep Kaan , Ozturk Izzet , Kinaci Cumali
Published: December 2007

The objective of this study was to implement a process model to simulate the dynamic behavior of a full‐scale anaerobic reactor treating corn processing wastewaters under mesophilic conditions. For this purpose, the IWA Anaerobic Digestion Model No.1 (ADM1) was applied to an expanded granular sludge bed reactor of an industrial wastewater treatment plant. The plant has a wastewater treatment capacity of 1594 m3/day. Sensitivity analysis showed that the influent characterization, based on disintegration into carbohydrates, proteins, lipids and inert components, had a large impact on the model outputs. An efficient correlation obtained between the measured and the simulated data, including effluent COD, pH and methane production, highlights good parameter optimization and wastewater characterization. This paper demonstrates a practical example for the application of the ADM1 to an agro‐industrial full‐scale anaerobic reactor.
Local self‐assembly mechanisms underlie the differential transformation of the proximal and distal cut axonal ends into functional and aberrant growth cones
Authors: Erez Hadas , Spira Micha E.
Published: December 2007

Following axotomy, both the proximal and distal cut axonal ends transform into growth cones (GCs). Whereas the GCs formed by the tip of the proximal segment branch to form neurites, the structure formed by the distal cut end fails to grow. The mechanisms underlying the formation of an aberrant GC by the distal cut end are not understood. Earlier we described the cascade that transforms the tip of the proximal cut axon into a GC. This involves microtubule (MT) polar reorientation, which culminates in the formation of two MT‐based vesicle traps, one for Golgi‐derived vesicles and the other that retains retrogradely transported vesicles. The formation of these traps is the outcome of local interactions between dynamically repolymerizing MTs and molecular motors. The concentration of Golgi‐derived vesicles in the plus‐end trap is essential for the successful generation of a functional GC. By using online confocal imaging of transected culturedAplysianeurons, we analyzed here the restructuring of the distal cut end after axotomy. We found that initially the proximal and distal cut ends undergo identical alterations. Nevertheless, in contrast to the proximal end, the distal cut axon forms only a minus‐end MT‐based trap that concentrates endocytotic vesicles driven by minus‐end oriented motors. Whereas the MTs forming the trap polymerize pointing their plus‐ends centrifugally to form finger‐like protrusions, the trapped vesicles cannot translocate out to fuse with the plasma membrane. Thus, the structure formed at the distal cut axon is incompetent to support growth processes. J. Comp. Neurol. 507:1019–1030, 2008. © 2007 Wiley‐Liss, Inc.
Transmission Holographic Polymer Dispersed Liquid Crystals Based on a Siloxane Polymer
Authors: Woo Ju Yeon , Kim Eun Hee , Kim Byung Kyu
Published: December 2007

The low surface energy and the great immiscibility of poly (dimethylsiloxane) (PDMS) with liquid crystals (LCs) are used in the fabrication of holographic polymer dispersed liquid crystals (HPDLCs). By adding increasing amounts of PDMS, the extent of the phase separation between the polymer and the LC, the LC channel width, and—eventually—also the diffraction efficiency of the film can be increased, while keeping the droplet size essentially the same. In addition, the presence of PDMS causes a decrease in the switching voltage and an increase in the response time. At an optimum content of PDMS (PUA40), a minimum switching voltage of 4 V μm−1, a rise time of 0.20 ms, and a decay of 14.75 ms were obtained. Regarding the effect of the LC content, an overshoot of the diffraction efficiency was observed when the amount of LC exceeded 35 %, which can be attributed to droplet coalescence.
Peripheral sensitization in migraine—role for P2X purinergic receptors in the dura–vascular sensory pathway
Authors: Jennings Ernest A. , Cho Hyun‐jung
Published: December 2007

Peripheral sensitization is still considered a prime contributor underlying the mechanisms of migraine. Trigeminal primary afferent neurons are the first neurons in the dural nociceptive pathway, and activation results in conscious perception of pain. Peripheral sensitization can lower the activation threshold of primary afferent neurons, rendering them more excitable, allowing for increases in release of neurotransmitter from both central and peripheral terminals. Increase in neurotransmitter release from central terminals contributes to excitation of second‐order neurons, while the release of peptides from peripheral terminals has been implicated in neurogenic inflammation. Adenosine 5′‐triphosphate (ATP) causes pain in human studies, and depolarize sensory neurons. There is evidence of the action of ATP at many levels in the dura–vascular sensory pathway. Animal studies have shown that some P2X receptors are located in neurons innervating the dura, including the P2X3 receptor, which is most often shown to be involved in nociceptive pathways. In this article, we briefly review peripheral sensitization in relation to migraine and provide emphasis for P2X receptor involvement where it is available. Drug Dev Res 68:321–328, 2007. © 2007 Wiley‐Liss, Inc.
Solid‐State Au/Hg Microelectrode for the Investigation of Fe and Mn Cycling in a Freshwater Wetland: Implications for Methane Production
Authors: Ma Shufen , Luther George W. , Keller Jason , Madison Andrew S. , Metzger Edouard , Emerson David , Megonigal J. Patrick
Published: December 2007

The solid‐state voltammetric gold‐amalgam microelectrode was used to measure multiple redox species (O, S, Fe and Mn) in situ at (sub)millimeter vertical resolution to elucidate rhizosphere processes in Jug Bay wetlands. In vegetated soil, a classic diagenetic redox sequence without any dissolved sulfide was observed in summer. However, the rhizosphere can be quite variable which is due to the introduction of O2 to the anoxic sediments by plants. In nonvegetated soil, the vertical concentration–depth profiles were relatively constant. The presence of Fe(II), Mn(II) and soluble Fe(III) in deeper sediments indicates the oxidation of Fe(II) as well as the nonreductive dissolution of Fe(III) and the reductive dissolution of Fe(III) and Mn(III, IV) solids. Mn(III, IV) and Fe(III) redox chemistry is important in organic matter mineralization mediated by bacteria and in suppressing methane formation. In addition, Mn(III, IV) also can oxidize Fe(II) to supply Fe(III) for bacterial Fe(III) reduction. Studying Fe and Mn cycling via voltammetric methods can give insights to methane production and loss as there is no methane sensor for sediment work at present.
Gel‐Integrated Voltammetric Microsensors and Submersible Probes as Reliable Tools for Environmental Trace Metal Analysis and Speciation
Authors: Tercier‐Waeber Mary‐Lou , Confalonieri Fabio , Koudelka‐Hep Milena , Dessureault‐Rompré Jacynthe , Graziottin Flavio , Buffle Jacques
Published: December 2007

This article gives a review of the analytical and environmental criteria which must be considered and the relevant specific developments needed for direct, reliable voltammetric measurements of trace metal speciation in environmental systems. In particular, this article will focus on the tools which enable remote, long‐term in situ measurements. The development of such tools is a challenging task. The strategies that can be used to achieve this goal are described for the development of innovative and versatile gel‐integrated voltammetric microsensors, micro‐/mini‐integrated analytical systems, and submersible probes. The advantages of these new tools with respect to selectivity, sensitivity, reliability, spatial and temporal resolution of data, and thus efficient environmental monitoring of the biogeochemical cycle of trace metals are demonstrated by providing examples of measurements made in various aquatic samples in laboratory (water, soils, solid–liquid interface) and in situ in fresh and seawaters.
Evaluation of Liquid‐ and Solid‐Contact, Pb2+‐Selective Polymer‐Membrane Electrodes for Soil Analysis
Authors: McGraw Christina M. , Radu Tanja , Radu Aleksandar , Diamond Dermot
Published: December 2007

Pb2+‐selective electrodes (ISEs) have been developed for the analysis of soil. Recent advances have extended the previous achievable limits of detection of ion‐selective electrodes (ISEs) to submicromolar levels, opening up possibilities for new applications in environmental analysis. The simple construction of ISE's, their low cost and low power demand, coupled with improved detection limits make the electrodes well suited for environmental analysis. In this paper, the development and use of both liquid‐ and solid‐contact ISEs for the detection of Pb2+ in a range of soil samples from abandoned mining sites is described. Solid‐contact electrodes were made using poly(3‐octylthipophene) as the internal mixed conductor layer. In addition, three techniques for the extraction of analyte from soil were studied in order to optimize the extraction of metal ions using techniques and solvents compatible with portable devices. Soil Pb2+ levels between 30 and 29,100 mg/kg were measured with the ISEs and were shown to be in good agreement with reference AAS measurements. Issues arising from the current definition and interpretation of ISE detection limits are also discussed.
A New Enzyme Immobilization Technique Based on Thionine‐Bovine Serum Albumin Conjugate and Gold Colloidal Nanoparticles for Reagentless Amperometric Biosensor Applications
Authors: Chen Shihong , Yuan Ruo , Chai Yaqin , Li Na
Published: December 2007

A novel enzyme immobilization technique based on thionine‐bovine serum albumin conjugate (Th‐BSA) and gold colloidal nanoparticles (nano‐Au) was developed. Thionine was covalently bound onto the BSA film with glutaraldehyde(GA) as cross‐linker to achieve Th‐BSA conjugate. The free amino groups of thionine were then used to attach nano‐Au for the immobilization of horseradish peroxidase (HRP). Such nano‐Au/Th‐BSA matrix shows a favorable microenvironment for retaining the native activity of the immobilized HRP and thionine immobilized in this way can effectively shuttle electrons between the electrode and the enzyme. The proposed biosensor displays excellent catalytic activity and rapid response for H2O2. The linear range for the determination of H2O2 is from 4.9×10−7 to 1.6×10−3 M with a detection limit of 2.1×10−7 M at 3σ and a Michaelies‐Menten constant K$\rm{ {_{M}^{app}}}$ value of 0.023 mM.
CE hydrogen deuterium exchange‐MS in peptide analysis
Authors: Lau Simon S. M. , Stainforth Nick M. , Watson David G. , Skellern Graham G. , Wren Stephen A. C , Tettey Justice N. A.
Published: December 2007

CE and hydrogen‐deuterium (H/D) exchange MS are useful tools in the analysis and characterisation of peptides. This study reports the facile coupling of these tools in the H/D exchange CE‐MS analysis of model and pharmaceutically important peptides, using a sheath flow interface. The peptides varied in mass from 556 (leucine enkephalin) to 1620 Da (bombesin), and in charge state from 0.33 (leucine enkephalin) to 3.0 (substance P). The application of a BGE composed of ammonium formate buffer (25 mM, pD 3.5 in D2O (>98% D atom)), a sheath liquid composed of formic acid (0.25% v/v in D2O) and ACN (30:70 v/v), and dissolving the samples in a mixture of ACN/D2O (50:50 v/v) facilitates complete H/D exchange. Because of complete H/D exchange the ESI mass spectra produced are easy to interpret and comparable to those obtained from LC‐MS analysis. The CE‐H/D‐MS approach has the advantage of requiring lower volumes of deuterated solvents. The b‐ and y‐series fragments produced by using in‐source decomposition correspond to those predicted. With the peptides studied, the complete exchange H/D exchange observed with both the molecular and fragment ions helps to confirm both amino acid composition and sequence.
CE of poly(amidoamine) succinamic acid dendrimers using a poly(vinyl alcohol)‐coated capillary
Authors: Desai Ankur , Shi Xiangyang , Baker James R.
Published: December 2007

Various generations (G1–G8) of negatively charged poly(amidoamine) (PAMAM) succinamic acid dendrimers (PAMAM‐SAH) were analyzed by CE using a poly(vinyl alcohol)‐coated capillary. Due to its excellent stability and osmotic flow‐shielding effect, highly reproducible migration times were achieved for all generations of dendrimer (e.g., RSD for the migration times of G5 dendrimer was 0.6%). We also observed a reverse trend in migration times for the PAMAM‐SAH dendrimers (i.e., higher generations migrated faster than lower generation dendrimers) compared to amine‐terminated PAMAM dendrimers reported in the literature. This reversal in migration times was attributed to the difference in counterion binding around these negatively charged dendrimers. This reverse trend allowed a generational separation for lower generation (G1–G3) dendrimers. However, a sufficient resolution for the migration peaks of higher generations (G4–G5) in a mixture could not be achieved. This could be due to their nearly identical charge/mass ratio and dense molecular conformations. In addition, we show that dye‐functionalized PAMAM‐SAH dendrimers can also be analyzed with high reproducibility using this method.
The effect of conditioning of fused‐silica capillaries on their electrophoretic performance
Authors: Gómez Jorge E. , Sandoval Junior E.
Published: December 2007

In CE practice, conditioning of the capillary tube with strong base, acid, or both in sequence, has been recognized as essential to obtain reasonable precision in electroosmotic mobility (EOM), and consequently, in the migration times of analytes. This report focuses on the comparative study of three different approaches for capillary conditioning: etching with HF, etching with NaOH, and leaching with HCl after NaOH treatment. EOM‐based measurements, including the hysteresis effect that characterizes the dependence of EOM with pH, were used to evaluate the conditioned silica surface. Additionally, indirect inspection of the conditioned surface was carried out by examining the electrophoretic profile of the cationic probe Ru(bpy)32+, known to strongly interact with the ionized silica surface while displaying no significant acid–base activity. It was shown that, once conditioned and prior to any CE measurement, extensive rinse of the capillary with the running electrolyte at high flow rate was essential to attain relatively rapid re‐equilibration of the tube with the fluid. Insufficient rinse with the running electrolyte would result in negatively biased EOM measurements and significant drift in migration times. It was also established that relatively high flow rates of 1 M NaOH conditioning solution (4–5 column volumes per minute) was required to attain capillaries with reproducible electrophoretic performance within a reasonable conditioning time (typically, 1 h). In addition to relatively more extensive rehydroxylation of the silica surface, evidenced by the highest EOM values obtained, the sequential use of NaOH‐etching and HCl‐leaching provided better precision than HF‐etching or NaOH‐etching alone.
A multiplex assay to identify 18 European mammal species from mixtures using the mitochondrial cytochrome b gene
Authors: Tobe Shanan S. , Linacre Adrian M. T.
Published: December 2007

A novel species‐specific multiplex to identify 18 common European mammalian species (badger, cat, cow, dog, donkey, fox, goat, guinea pig, harvest mouse, hedgehog, horse, house mouse, human, pig, rabbit, rat, red deer and sheep), many of which are often associated with forensic investigations, has been developed. The assay is based on the mitochondrial cytochrome b gene, which is commonly used in species identification and phylogeny studies. Areas of homology and variation were identified and were used to create universal and species‐specific primers. The species‐specific primers were designed such that they will only react with the species for which they were designed. Two primer sets were designed for each species making the test self‐confirmatory. All primer sets produced the expected results. The multiplex was balanced at template concentration of 40 000 copies (approximately 1.36 pg). Validation was accomplished by analysing the same sample ten times to determine run variation and several samples for each species to determine between‐sample variation. Twenty‐eight additional mammalian species were reacted with the multiplex. The multiplex provides, for the first time, a definitive method for identification of species in a forensic context.
Type III neuregulin‐1 promotes oligodendrocyte myelination
Authors: Taveggia Carla , Thaker Pratik , Petrylak Ashley , Caporaso Gregg L. , Toews Arrel , Falls Douglas L. , Einheber Steven , Salzer James L.
Published: December 2007

The axonal signals that regulate oligodendrocyte myelination during development of the central nervous system (CNS) have not been established. In this study, we have examined the regulation of oligodendrocyte myelination by the type III isoform of neuregulin‐1 (NRG1), a neuronal signal essential for Schwann cell differentiation and myelination. In contrast to Schwann cells, primary oligodendrocytes differentiate normally when cocultured with dorsal root ganglia (DRG) neurons deficient in type III NRG1. However, they myelinate type III NRG1‐deficient neurites poorly in comparison to wild type cultures. Type III NRG1 is not sufficient to drive oligodendrocyte myelination as sympathetic neurons are not myelinated even with lentiviral‐mediated expression of NRG1. Mice haploinsufficient for type III NRG1 are hypomyelinated in the brain, as evidenced by reduced amounts of myelin proteins and lipids and thinner myelin sheaths. In contrast, the optic nerve and spinal cord of heterozygotes are myelinated normally. Together, these results implicate type III NRG1 as a significant determinant of the extent of myelination in the brain and demonstrate important regional differences in the control of CNS myelination. They also indicate that oligodendrocyte myelination, but not differentiation, is promoted by axonal NRG1, underscoring important differences in the control of myelination in the CNS and peripheral nervous system (PNS). © 2007 Wiley‐Liss, Inc.
Ultrastructural plasticity in the rat suprachiasmatic nucleus. Possible involvement in clock entrainment
Authors: Becquet Denis , Girardet Clémence , Guillaumond Fabienne , François‐Bellan Anne‐Marie , Bosler Olivier
Published: December 2007

Circadian rhythms in mammals are synchronized to the light (L)/dark (D) cycle through messages relaying in the master clock, the suprachiasmatic nucleus of the hypothalamus (SCN). Here, we provide evidence that the SCN undergoes rhythmic ultrastructural rearrangements over the 24‐h cycle characterized by day/night changes of the glial, axon terminal, and/or somato‐dendritic coverage of neurons expressing arginine vasopressin (AVP) or vasoactive intestinal peptide (VIP), the two main sources of SCN efferents. At nighttime, we noted an increase in the glial coverage of the dendrites of the VIP neurons (+29%) that was concomitant with a decrease in the mean coverage of the somata (−36%) and dendrites (−43%) of these neurons by axon terminals. Conversely, glial coverage of the dendrites of AVP neurons decreased (−19%) with parallel increase in the extent of somatal (+96%) and dendritic (+52%) membrane appositions involving these neurons. These plastic events were concomitant with daily fluctuations in quantitative expression of glial fibrillary acidic protein (GFAP), which were then used as an index of structural plasticity. The GFAP rhythm appeared to be strictly dependent on light entrainment, indicating that structural reorganization of the SCN may subserve synchronization of the clock to the L/D cycle. Other results presented reinforced this view while showing that circulating glucocorticoid hormones, which are known to modulate photic entrainment, were required to maintain amplitude of the GFAP rhythm to normal values. © 2007 Wiley‐Liss, Inc.
Tissue engineered cartilage from hTGF β2 transduced human adipose derived stem cells seeded in PLGA/alginate compound in vitro and in vivo
Authors: Jin Xiao Bing , Sun Yong Sheng , Zhang Ke , Wang Jing , Shi Tai Ping , Ju Xiao Dong , Lou Si Quan
Published: December 2007

Chondrogenic potential of human adipose derived stem cells (hASCs) makes them a possible source of seeding cells for cartilage tissue engineering. We aim to examine the chondrogenic differentiation of human transforming growth factor β2 (hTGF β2) transduced hASCs seeded in three‐dimensional scaffold in vitro and in vivo. In this study, hASCs were isolated from human subcutaneous adipose tissue and transduced with a replication deficient adenovirus carrying hTGF β2 (Ad5‐hTGF β2), and then the transduced cells were seeded and cultured in PLGA/alginate compounds. RT‐PCR analysis revealed that Ad5‐hTGF β2 transduced hASCs produced aggrecan and collagen type II after 7‐day induction in vitro and continued throughout the culture period; this was also demonstrated by the positive staining of Alcian blue and immunohistochemistry for collagen type II. For in vivo study, Ad5‐hTGF β2 transduced hASCs seeded in PLGA/alginate compounds were implanted in subcutaneous pockets of nude mice; after 12 weeks, the implants were harvested and examined by haematoxylin and eosin staining, AB‐PAS staining, and immunohistochemical analysis, and the results demonstrated the formation of cartilage tissue. As a control, all these were not observed in the constructs with Ad5‐EGFP transduced hASCs. In conclusion, our study demonstrates that adenovirus‐mediated hTGF β2 gene transfer is able to induce the hASCs into chondrogenic lineage both in vitro and in vivo. Ad5‐hTGF β2 transduced hASCs combined with three‐dimensional PLGA/alginate compound may be a viable method in treating injuries of cartilage. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Subcutaneous transplantation of autologous oral mucosal epithelial cell sheets fabricated on temperature‐responsive culture dishes
Authors: Obokata Haruko , Yamato Masayuki , Yang Joseph , Nishida Kohji , Tsuneda Satoshi , Okano Teruo
Published: December 2007

The oral mucosa is an attractive cell source for autologous transplantation in human patients who require regenerative therapies of various epithelia. However, the time‐course of cellular changes in transplanted oral mucosal epithelia at ectopic sites remains poorly understood. By applying a rat model, we analyzed phenotypic changes in oral mucosal epithelial cell sheets after harvest from temperature‐responsive culture dishes and subsequent autologous subcutaneous transplantation. We used monoclonal antibodies to identify epithelial‐specific cytokeratins 4, 10, 13, and 14, the stem/progenitor cell marker p63, and proliferating cell nuclear antigen, within the regenerated tissues. Transplanted oral mucosal epithelial cell sheets proliferated during the first week after grafting in conjunction with host inflammation, but then began to degenerate afterward with complete disappearance after 3 weeks. Our findings suggest that host subcutaneous tissues support proliferation and differentiation of the oral mucosal epithelial cell sheets, but are unable to promote maintenance of stem and progenitor cells and therefore cannot produce long‐term survivability. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Stimulation of osteogenic activity in mesenchymal stem cells by FK506
Authors: Dai Wenda , Dong Jian , Fang Taolin , Uemura Toshimasa
Published: December 2007

The aim of this study was to investigate the osteogenic induction by tacrolimus hydrate (FK506) of rat bone marrow‐derived mesenchymal stem cells (MSCs). MSCs were cultured in α‐MEM containing either (1) L‐ascorbic acid‐2‐phosphate (AsAP) and β‐glycerophosphate (β‐GP) as a control; (2) AsAP and β‐GP plus FK506; (3) AsAP and β‐GP plus Dex; or (4) AsAP and β‐GP plus FK506 and Dex. The concentration of FK506 was varied from 5 to 5000 nM to investigate the dose–effect relationship. Sixteen days later, cells were harvested for analysis. Examination of morphology, alkaline phosphatase (APase) activity, calcium deposition, bone nodule formation, osteocalcin mRNA expression, and mineralized extracellular matrix formation showed that the osteogenic differentiation of MSCs was greatly promoted, bone nodule formation was enhanced, APase activity and the expression of osteocalcin mRNA were increased. FK506 was much more effective when combined with Dex. The best results were achieved with α‐MEM containing 0.25 mM AsAP, 10 mM β‐GP, 10 nM Dex, and 50 nM FK506. Formation of bone in vivo was also studied by transplanting MSCs‐loaded ceramic cubes subcutaneously into the back of rats. Satisfactory results were achieved at 4 and 8 weeks. FK506 should be considered for use as an osteogenic agent. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Antibacterial properties and corrosion resistance of Cu and Ag/Cu porous materials
Authors: Jing Hemin , Yu Zhiming , Li Li
Published: December 2007

The porous materials of Cu and Ag/Cu were successfully prepared by the electrodeposition on a precursor of conventional polyamide foam. The microstructure of the porous materials was observed by scanning electron microscope. Their porosity and specific surface area were measured. The inhibition effect of Cu porous materials against E. coli was also investigated. The broad‐spectrum of antibiosis of the Cu and Ag/Cu porous materials were characterized. The corrosion resistance of Cu, Ag/Cu coatings was also compared. The shape and size of pores are uniform in three directions for the porous materials. Their porosity may reach above 95% and specific surface area is beyond 12.8 m2/m3. The antibacterial test results show that the Cu porous materials not only exhibited high antibacterial effect and good broad‐spectrum antibacterial properties, but also excellent persistent antibacterial effects; the antibacterial effects, and broad‐spectrum of antibiosis were greatly improved through the deposition of a thin Ag coating on the surface of Cu porous material. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008