bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isolation of FRET‐positive cells using single 408‐nm laser flow cytometry
Authors: van Wageningen Sake , Pennings Arie H. , van der Reijden Bert A. , Boezeman Jan B. , de Lange Frank , Jansen Joop H. 
Published: February 2006

AbstractBackground:Flow cytometry may be used to isolate large amounts of living, fluorescently labeled cells. Certain fluorescent labels, like enhanced cyan fluorescent protein (ECFP) and enhanced yellow fluorescent protein (EYFP), allow the assessment of direct protein–protein interaction in situ, by fluorescence resonance energy transfer (FRET). However, current flow cytometric methods either require elaborate technical adaptations or, using a single laser protocol, are hampered by background signal. We optimized a single 408‐nm laser protocol to detect FRET between ECFP/EYFP‐tagged proteins.Methods:Cell lines stably expressing ECFP and/or EYFP or an EYFP‐ECFP fusion protein were used to design the settings for the flow cytometer to detect FRET‐positive cells using a single 408‐nm laser. Using these settings, interactions between the subunits of the transcription factor NF‐Y were studied.Results:Flow cytometric analysis of the cells expressing an EYFP‐ECFP fusion protein yielded a discrete FRET‐positive population. Using the same settings, in cells expressing NF‐YB‐CFP and NF‐YC‐YFP fusion proteins, FRET could also be detected. These cells were sorted and FRET was confirmed by confocal microscopy.Conclusion:FRET‐positive cells, expressing ECFP‐ and EYFP‐tagged proteins, can be detected using single 408‐nm laser excitation, with low background signal. This allows high‐throughput analysis and isolation of viable FRET‐positive and ‐negative cells for subsequent biological experiments. © 2006 International Society for Analytical Cytology
Pharmacodynamic monitoring of BAY 43‐9006 (Sorafenib) in phase I clinical trials involving solid tumor and AML/MDS patients, using flow cytometry to monitor activation of the ERK pathway in peripheral blood cells
Authors: Tong Frances K. , Chow Sue , Hedley David 
Published: February 2006

AbstractBackgroundWe previously reported a flow cytometry technique to monitor pharmacodynamic effects of the raf kinase inhibitor BAY 43‐9006 based on the ability of phorbol ester (PMA) to phosphorylate extracellular‐regulated kinase (ERK) in peripheral blood (Chow et al., Cytometry 2001;46:72–78). In this article, we describe its application to phase I trials of BAY 43‐9006 in solid tumor and AML/MDS patients.MethodsThe previously described whole blood lysis method was used to monitor BAY 43‐9006 effects on peripheral T‐cells of solid tumor patients. A modified whole blood fixation protocol was developed for the AML/MDS trial, using the c‐kit ligand stem cell factor (SCF) to activate ERK as an alternative to PMA, and incorporating immunophenotypic markers to identify leukemic blasts.ResultsAt all dose levels of BAY 43‐9006 used to treat solid tumor patients, ERK could be activated by PMA in peripheral T‐cells and we were not able to show inhibition of raf kinase. A similar effect was seen in the lymphocytes of AML/MDS patients during treatment with BAY 43‐9006. However, we found strong inhibition when ERK was activated via c‐kit using SCF. Furthermore, normal donor CD34+ve stem cells were much more sensitive to BAY 43‐9006 when ERK was activated by SCF, compared to PMA.ConclusionsThese findings support the further development of flow cytometry applications to monitor signal transduction inhibitors during early phase clinical trials. © 2006 International Society for Analytical Cytology
Synthesis, Crystal Structures, and Photophysical Properties of Two Novel Lead(II)–SIP Coordination Polymers (NaH2SIP = 5‐Sulfoisophthalic Acid Monosodium Salt) Containing Tetranuclear Lead(II) Units
Authors: Liu Qing‐Yan , Xu Li 
Published: February 2006

AbstractTwo new PbII–SIP coordination polymers, {[Pb4(OH)2(SIP)2(H2O)](H2O)5}n (1) and [Pb3(SIP)2(H2O)5]n (2), have been synthesized by hydrothermal reactions of Pb(OH)2 or Pb(NO3)2 and 5‐sulfoisophthalic acid monosodium salt (NaH2SIP) at 160 °C, respectively. Single‐crystal X‐ray diffraction reveals that compound 1 has a 2D brick‐wall‐like architecture constructed from 1D tapes containing the basketlike tetranuclear [Pb4(μ3‐OH)2(COO)2]. Compound 2 has a 2D‐layered structure, which is constructed from a 1D‐ladder structure composed of the cyclic [Pb4(SIP)2(COO)2] grid with the four Pb atoms nearly coplanar. In the solid state, compound 1 exhibits blue photoluminescence with the maximum emission intensity at 436 nm upon excitation at 335 nm. Compound 2 shows phosphorescence with the maximum emission intensity at 603 nm upon excitation at 426 nm. Both compounds have also been characterized by elemental analysis, IR spectra, TG analysis, and powder X‐ray diffraction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
13C Chemical Shifts and 1JCH Coupling Constants of Cytidine at Different χ Dihedrals Based on DFT Calculations
Authors: Fischer Jörg T. , Reinscheid Uwe M. 
Published: February 2006

AbstractA molecular dynamic simulation of cytidine reproduced the dominating 3E‐endo, the so‐called North conformation of the sugar and the anti base orientation with χ = –120°. Taken as starting structures for a geometry optimisation, 13C chemical shifts and 1J coupling constants were calculated by DFT [functional: B3LYP, basis set: 6‐31G(d,p)]. As for the first time no minimal structural model was used, the results can be interpreted without further approximations except solvent dependence which was not included. The influence of the glycosidic torsion angle was studied. The 13C chemical shifts correlated with a North conformation of the sugar independent of the base orientation when using an empirically derived coordinate analysis. However, the 1JCH coupling constants and 13C chemical shifts clearly showed a dependence on the glycosidic torsion which enables the identification of χ. The 1JCH analysis showed that the sugar pucker is not the major determinant for 1JC1′H1′. Instead, the base orientation caused major changes, with a maximal difference of 14 Hz. Additionally, 1JC2′H2′, 1JC3′H3′ and 1JC4′H4′ are differently influenced by the glycosidic torsion which can be exploited for assigning χ. Analysis of electrostatic and steric effects showed that an isolated view is not able to explain all NMR spectroscopic data but gives some useful ideas. A higher charge on C3′ and the 1JC6H6 coupling constants were explained by through‐space effects. Depending on the glycosidic torsion, the base non‐planarity changes substantially. The results clearly show that also for ribonucleotides 13C chemical shifts and 1JCH coupling constants are dependent on the base orientation which was questioned in the past.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Isomerization of 3H‐ to 2H‐[1]Benzothieno[3,2‐b]pyrroles and Synthesis of the First Merocyanine Dyes Based on Them
Authors: Shimkin Alexey A. , Shirinian Valerii Z. , Nikalin Denis M. , Krayushkin Mikhail M. , Pivina Tatiana S. , Troitsky Nikolay A. , Vorontsova Ludmila G. , Starikova Zoya A. 
Published: February 2006

AbstractNew 2H‐[1]benzothieno[3,2‐b]pyrroles were synthesized by a [1,5]‐sigmatropic shift of 3H‐benzothienopyrroles. The dependence of the rearrangement on solvent and temperature was studied. The first merocyanine dyes based on both 3H‐ and 2H‐benzothienopyrroles were synthesized and characterized by NMR‐ and UV/Vis spectroscopy, mass spectrometry, and X‐ray crystallography.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
The Electrochemical Properties of Co(TPP), Tetraphenylborate Modified Glassy Carbon Electrode: Application to Dopamine and Uric Acid Analysis
Authors: Zeng Yunlong , Li Chunxiang , Tang Chunran , Zhang Xiao‐Bing , Shen Guoli , Yu Ruqin 
Published: February 2006

AbstractWe report the combination of the charge repelling property of tetraphenyl‐borate (TPB) anion and the electrooxidation catalytic effect of cobalt(II) tetrakisphenylporphyrin (CoTPP) embedded in a sol gel ceramic film to develop a modified glassy carbon electrode (CoTPP‐TPB‐SGGCE) for the simultaneous determination of dopamine (DA) and uric acid (UA). The optimized CoTPP‐TPB‐SGGCE shows excellent sensitivity and selectivity for the DA and UA analysis. As high as 2000 fold acceptable tolerance of ascorbic acid (AA) for the determination of trace DA and UA is reached. In the presence of 0.10 mM AA, the linear concentration range for DA is from 6.0×10−8 to 2.5×10−5 M, and the detection limit is 2.0×10−8 M. For UA, the linear concentration range is from 1.0×10−7 to 3.5×10−5 M, and the detection limit is 7.0×10−8 M. Our study has also demonstrated that the novel CoTPP‐TPB‐SGGCE shows high stability and reliability. For 6.00 μM DA and UA, a total of 12 measurements were taken in one week, and the relative standard deviation is 2.05% and 2.68% respectively. No obvious shift of peak current and peak potential is observed over a three‐month lifetime test. The response of the sensor is very quick and response time is approximately 1 s. Satisfactory results are also achieved when the CoTPP‐TPB‐SGGCEs being used to detect the DA and UA in human urine samples.
Centralizing the non‐central chi‐square: a new method to correct for population stratification in genetic case‐control association studies
Authors: Gorroochurn Prakash , Heiman Gary A. , Hodge Susan E. , Greenberg David A. 
Published: February 2006

AbstractWe present a new method, the δ‐centralization (DC) method, to correct for population stratification (PS) in case‐control association studies. DC works well even when there is a lot of confounding due to PS. The latter causes overdispersion in the usual chi‐square statistics which then have non‐central chi‐square distributions. Other methods approach the non‐centrality indirectly, but we deal with it directly, by estimating the non‐centrality parameter τ itself. Specifically: (1) We define a quantity δ, a function of the relevant subpopulation parameters. We show that, for relatively large samples, δ exactly predicts the elevation of the false positive rate due to PS, when there is no true association between marker genotype and disease. (This quantity δ is quite different from Wright's FST and can be large even when FST is small.) (2) We show how to estimate δ, using a panel of unlinked “neutral” loci. (3) We then show that δ2 corresponds to τ the non‐centrality parameter of the chi‐square distribution. Thus, we can centralize the chi‐square using our estimate of δ; this is the DC method. (4) We demonstrate, via computer simulations, that DC works well with as few as 25–30 unlinked markers, where the markers are chosen to have allele frequencies reasonably close (within ±.1) to those at the test locus. (5) We compare DC with genomic control and show that where as the latter becomes overconservative when there is considerable confounding due to PS (i.e. when δ is large), DC performs well for all values of δ. Genet. Epidemiol. 2006. © 2006 Wiley‐Liss, Inc.
Is there a case for using visual analogue scale valuations in cost‐utility analysis?
Authors: Parkin David , Devlin Nancy 
Published: February 2006

AbstractThis paper critically reviews theoretical and empirical propositions regarding visual analogue scale (VAS) valuations of health states and their use in cost‐utility analysis (CUA). A widely repeated assertion in the economic evaluation literature is the inferiority, on theoretical grounds, of VAS valuations. Five common criticisms are: VAS lacks a theoretical foundation; VAS values are not ‘choice based’; VAS values are not consistent with utility‐under‐uncertainty requirements; context and range effects observed in VAS valuation data mean that they cannot even be considered to represent measurable value functions; and when completing a VAS, people are not trying to express values.We address each of these points: the VAS does have a theoretical basis, being entirely consistent with the non‐welfarist foundations of QALYs and CUA; the ‘choiceless’ nature of the VAS is incorrectly judged by stated preference criteria relevant to monetary rather than health state valuations, and VAS valuations do in any case involve an element of choice; because valuations are intended for use in social decision‐making, it may be advantageous that VAS values are elicited under conditions of certainty; although there are measurement problems with the VAS, means such as better design and transformations of data can deal with these; and with any method of eliciting values, it is unrealistic to expect people consciously to think in terms of social science constructs such as utilities.Moreover, there are problems, both theoretical and empirical, with alternative methods. Selection of the appropriate valuation method should be based on empirical performance, and in this the VAS has important advantages. We conclude that there are strong grounds for disputing the consensus view against the VAS and challenge those who hold it to deploy more convincing arguments and evidence in favour of alternative methods. However, we identify areas where further research is required to establish and consolidate the potential of the VAS as a valuation method. Copyright © 2006 John Wiley & Sons, Ltd.
Free choice of health plan combined with risk‐adjusted capitation payments: are switchers and new enrolees good risks?
Authors: van Vliet René C.J.A. 
Published: February 2006

AbstractIt is well established in the literature that the young and healthy are more inclined to switch health plan, given the opportunity. In countries where risk‐adjusted capitation payments are used to create a level playing field for the competing health plans, as is the case in The Netherlands, it is important to determine whether plans could exploit such selective switching to gain unfair advantage. This study analyses whether various risk‐adjustment models are capable of compensating adequately for selective switching in the Dutch sickness fund sector. Data concern information on health care expenditures, demographics and indicators of chronic diseases for 10 million members from 21 funds. Results indicate that switchers in 2000–2001 had expenditures that were around 40% below average in 1994–2002, confirming that movers are ‘good’ risks in absolute terms. However, after taking into account that these people are younger and healthier, the risk‐adjusted payments for them nearly equalled actual expenditures. This holds for both people who in fact switched from one fund to another, and for those who were forced by regulation to leave the private insurance sector and who had to choose a sickness fund. Importantly, models using only demographics could not achieve this. Copyright © 2006 John Wiley & Sons, Ltd.
A re‐examination of the impact of reference pricing on anti‐hypertensive drug plan expenditures in British Columbia
Authors: Grootendorst Paul , Stewart David 
Published: February 2006

AbstractReference pricing (RP) limits drug plan reimbursement of interchangeable medicines to a reference price, which is typically equal to the price of the lowest‐cost interchangeable drug; any cost above that is borne by the patient. Much of the evidence of the effects of RP comes from ‘before and after’ studies of the RP scheme adopted by Pharmacare, the publicly funded drug plan for seniors and others in British Columbia, Canada. We critically assess the identifying assumption inherent in the before and after design – namely, that pre‐RP trends accurately predict counterfactual outcomes – in the context of estimating the impact of RP on Pharmacare's expenditure on anti‐hypertensive drugs for its senior beneficiaries. We use similar data from a public plan that has not introduced RP to estimate the effects on drug expenditures of patent expiration, secular changes in prescribing patterns and various other factors common to all Canadian public drug plans that could potentially confound the before and after estimates of the effect of RP on drug plan expenditures. We find that controlling for such factors reduces estimates of drug plan savings attributable to RP of the Calcium Channel Blockers by about half. Copyright © 2006 John Wiley & Sons, Ltd.
Alkylation of phenol with tert‐butyl alcohol over a catalyst synthesized from coal fly ash
Authors: Ojha Keka , Pradhan Narayan C , Samanta Amar Nath 
Published: February 2006

AbstractThe alkylation of phenol with tert‐butyl alcohol was carried out in a continuous flow reactor over a catalyst synthesized from fly ash. The activity of the synthesized catalyst was compared with those of other conventional zeolite catalysts such as 13X (NaX) and Hβ. Of all the catalysts tested, zeolite Hβ showed the highest activity in phenol conversion followed by the synthesized zeolite (HZOP‐31). The activity of commercial 13X zeolite was found to be same as that of HZOP‐31. Ce‐exchanged catalyst (CeZOP‐31) showed even better performance than 13X in the alkylation of phenol. The effects of different parameters such as reactant mole ratio, temperature and space velocity on phenol conversion and tert‐butyl phenol selectivity were studied. The effect of mass transfer resistance was found to be negligible within the feed rate range and particle size range studied. The apparent activation energy for the reaction of tert‐butyl alcohol over HZOP‐31 was determined as 30.1 kJ mol−1. Copyright © 2006 Society of Chemical Industry
Volumetric mass transfer coefficients in an internal loop airlift reactor with low‐density particles
Authors: Muthukumar Karuppan , Velan Manickam 
Published: February 2006

AbstractThe influence of organic additives (propanol, benzoic acid, isoamyl alcohol and carboxymethylcellulose) on the volumetric mass transfer coefficient, kLa, in an internal loop airlift reactor with low‐density particles (nylon‐6 and polystyrene) was investigated. The kLa values increased with increase in superficial gas velocity, Usg, and decreased with increase in solid loading. A draft tube to reactor diameter ratio, DR/D, of 0.4 gave maximum kLa values. The addition of benzoic acid and propanol increased the kLa values owing to their coalescence inhibiting characteristics. The addition of isoamyl alcohol decreased kLa, owing to the formation of rigid bubbles and recirculation of small bubbles having a low oxygen content. The kLa values decreased with increase in the concentration of the non‐Newtonian fluid carboxymethylcellulose (CMC). The proposed correlations predicted the experimental data well. Copyright © 2006 Society of Chemical Industry
A calibration methodology and model‐based systems analysis for SBRs removing nutrients under limited aeration conditions
Authors: Insel Güçlü , Sin Gürkan , Lee Dae Sung , Nopens Ingmar , Vanrolleghem Peter A 
Published: February 2006

AbstractA methodology is proposed for the model calibration of nutrient‐removing laboratory‐scale SBRs under limited aeration. Based on in‐process measurements and influent wastewater characterization, the ASM2d model was modified by adding an organic nitrogen module incorporating a hydrolysis mechanism. After calibration, the simulation results showed that enhanced biological nutrient removal occurred during the fill period and under reduced aeration achieving so‐called ‘simultaneous nutrient removal’. A model‐based systems analysis was performed in terms of the contributions of different processes to overall oxygen, nitrogen and phosphate utilization. In each phase, simultaneously occurring biological reactions were compared using the calibrated model. According to the calibrated model, 61% of all denitrified nitrate is denitrified during the mixing/filling phase. On the other hand, 17% of all denitrified nitrate is consumed by simultaneous nitrification–denitrification during the first aerobic period. The aerobic and anoxic P‐removals were quantified as 73% and 12%, respectively. Copyright © 2006 Society of Chemical Industry
Investigations of cell immobilization in alginate: rheological and electrostatic extrusion studies
Authors: Manojlovic Verica , Djonlagic Jasna , Obradovic Bojana , Nedovic Viktor , Bugarski Branko 
Published: February 2006

AbstractIn this study, the process of electrostatic extrusion as a method for cell immobilization was investigated. We have assessed the effects of concentrations of yeast cells (as a model cell type) and Na alginate on the size of the resulting microbeads and attempted to rationalize the obtained findings by rheological characterization of the cell–alginate suspensions. Under the investigated conditions, microbeads, 50–600 µm in diameter, were produced and the increase in both alginate and cell concentrations resulted in larger microbeads with their sizes having higher standard deviations. Rheological characterization revealed non‐Newtonian, pseudoplastic behavior of cell–alginate suspensions with higher viscosities at higher alginate concentrations. However, the presence of cells even at high concentrations (5 × 108 and 1 × 109 cells mL−1) did not significantly affect the rheological properties of the Na alginate solution. Finally, we have investigated the kinetics of alginate gelation with respect to the quantity of Ca2+ ions and the presence of cells. The molar ratio of α‐L‐guluronic acid units to Ca2+ ions of 4:1 provided complete crosslinking. The presence of cells decreased the rate of network formation as well as the strength of the obtained Ca alginate hydrogel. Copyright © 2006 Society of Chemical Industry
Effect of activation type on bioregeneration of various activated carbons loaded with phenol
Authors: Aktaş Özgür , Çeçen Ferhan 
Published: February 2006

AbstractThermally and chemically activated powdered carbons (PAC), and their granular countertypes (GAC) with similar physical characteristics were used to investigate the extent of bioregeneration in laboratory‐scale activated sludge reactors. Bioregeneration of activated carbon was determined by measurement of bulk phenol concentrations and loadings remaining on activated carbon. It was also followed by oxygen uptake rate measurements. For the carbons used in this study, bioregeneration of chemically activated carbons was found to be higher than thermally activated ones. This was in accordance with their higher reversibility of adsorption and showed that bioregeneration was controlled by the reversibility of adsorption. Oxidative polymerization of phenol was a plausible explanation for low bioregeneration of thermally activated carbons. However, bioregeneration efficiencies of thermally activated carbons were much higher than their total desorbabilities. This unexpectedly high bioregeneration indicated that some exoenzymatic reactions had occurred. These results suggest that carbon activation type is of crucial importance for bioregeneration. PAC and GAC countertypes showed comparable bioregeneration efficiencies indicating that carbon size was not an effective factor. The environmental scanning electron microscopy (ESEM) studies showed that microorganisms were attached both on the external surface and interval cavities of activated carbon particles. Copyright © 2006 Society of Chemical Industry
Strategic giving and the nursing shortage
Authors: Ullmann Steven G. , Martin Pamela , Kelly Catherine , Homer Jenny 
Published: February 2006

Abstract

Health care organizations in the United States face a significant nursing shortage, which seriously impacts the quality and availability of health care. Confronting this challenge requires involvement from organizations beyond the public sector. This paper explores an initiative by Blue Cross and Blue Shield of Florida, exemplifying the concept of ‘strategic philanthropy,’ to contribute their financial resources and strong institutional ties to respond to the current and future shortage of nurses in Florida. Through this intervention, the company and partnering organizations hope to benefit the health care sector, the public, and themselves from the outcomes associated with the generation of a greater supply of nurses.

Copyright © 2006 John Wiley & Sons, Ltd.