bluuebunny/crossref_metadata_2025_split huggingface dataset:
Random error reduction in analytic hierarchies: a comparison of holistic and decompositional decision strategies
Authors: Morera Osvaldo F. , Budescu David V. 
Published: August 2002

AbstractThe principle of ‘divide and conquer’ (DAC) suggests that complex decision problems should be decomposed into smaller, more manageable parts, and that these parts should be logically aggregated to derive an overall value for each alternative. Decompositional procedures have been contrasted with holistic evaluations that require decision makers to simultaneously consider all the relevant attributes of the alternatives under consideration (Fischer, 1977). One area where decompositional procedures have a clear advantage over holistic procedures is in the reduction of random error (Ravinder, 1992; Ravinder and Kleinmuntz, 1991; Kleinmuntz, 1990). Adopting the framework originally developed by Ravinder and colleagues, this paper details the results of a study of the random error variances associated with another popular multi‐criteria decision‐making technique, the Analytic Hierarchy Process (AHP); (Saaty, 1977, 1980), as well as the random error variances of a holistic version of the Analytic Hierarchy Process (Jensen, 1983). In addition, data concerning various psychometric properties (e.g. the convergent validity and temporal stability) and values of AHP inconsistency are reported for both the decompositional and holistic evaluations. The results of the study show that the Ravinder and Kleinmuntz (1991) error‐propagation framework extends to the AHP and decompositional AHP judgments are more consistent than their holistic counterparts. Copyright © 2001 John Wiley & Sons, Ltd.
Ultra‐wideband pulses increase nitric oxide production by RAW 264.7 macrophages incubated in nitrate*†
Authors: Seaman Ronald L. , Parker Jill E. , Kiel Johnathan L. , Mathur Satnam P. , Grubbs Teri R. , Prol H. Kenneth 
Published: August 2002

AbstractThe possible effects of ultra‐wideband (UWB) pulses on cellular nitric oxide production were tested by measuring nitrite in the medium bathing UWB exposed RAW 264.7 macrophages. A 30 min exposure to 1 ns UWB pulses, repeated at 600 Hz with an estimated SAR of 0.106 W/kg, did not change nitric oxide production by RAW 264.7 cells, with or without stimulation by gamma interferon and lipopolysaccharide. However, when nitrate was added to the medium of stimulated cells, nitric oxide production increased after UWB exposure, indicating a possible action of UWB pulses on induced nitric oxide synthase under certain conditions. Bioelectromagnetics 23:83–87, 2002. © 2002 Wiley‐Liss, Inc.
Vetulicolians—are they deuterostomes? chordates?
Authors: Lacalli Thurston C. 
Published: August 2002

AbstractA recent paper by Shu et al.(1) reinterprets the fossil Vetulicola and related forms, all from the Lower Cambrian, as basal deuterostomes, assigning them their own phylum, Vetulicolia. Their conclusion is based on the presence of structures resembling gill slits and a trunk‐like region that shows evidence of segmentation. This report summarizes the fossil evidence for their interpretation and evaluates a possible alternative, that vetulicolians may instead be tunicate‐like chordates. Implications for our understanding of the nature of the primitive deuterostome (and chordate) body plan are discussed. BioEssays 24:208–211, 2002. © 2002 Wiley Periodicals, Inc.; DOI 10.1002/bies.10064
The tree of life and the rock of ages: Are we getting better at estimating phylogeny?
Authors: Wills Matthew A. 
Published: August 2002

AbstractIn a recent paper,(1) palaeontologist Mike Benton claimed that our ability to reconstruct accurately the tree of Life may not have improved significantly over the last 100 years. This implies that the cladistic and molecular revolutions may have promulgated as much bad “black box” science as rigorous investigation. Benton's assessment was based on the extent to which cladograms (typically constructed with reference only to distributions of character states) convey the same narrative as the geochronological ages of fossil taxa (an independent data set). Fossil record quality varies greatly between major clades, and the palaeontological dating “yardstick” may be more appropriate for some groups than others. BioEssays 24:203–207, 2002. © 2002 Wiley Periodicals, Inc.; DOI 10.1002/bies.10065.
Helicase homologues maintain cytosine methylation in plants and mammals
Authors: Bourc'his Déborah , Bestor Timothy H. 
Published: August 2002

AbstractThe Arabidopsis DDM1 gene is required for the maintenance of genomic methylation patterns but is a helicase homolog of the SWI2/SNF2 family rather than a DNA methyltransferase.(1) Dennis et al.(2) have shown that disruption of the mouse Lsh gene, the mammalian gene most closely related to DDM1, causes demethylation of the mouse genome. This result suggests that the mechanisms that maintain methylation patterns in the genomes of mammals and flowering plants are more conserved than previously suspected. BioEssays 24:297–299, 2002. ©2002 Wiley Periodicals, Inc.
Innate immunity and its evasion and suppression by hymenopteran endoparasitoids
Authors: Schmidt Otto , Theopold Uli , Strand Mike 
Published: August 2002

AbstractRecent studies suggest that insects use pattern recognition molecules to distinguish prokaryotic pathogens and fungi from “self” structures. Less understood is how the innate immune system of insects recognizes endoparasitic Hymenoptera and other eukaryotic invaders as foreign. Here we discuss candidate recognition factors and the strategies used by parasitoids to overcome host defense responses. We suggest that host–parasitoid systems are important experimental models for studying how the innate immune system of insects recognizes foreign invaders that are phylogenetically more closely related to their hosts. The strategies used by parasitoids suggest that insects may employ “hidden‐self” recognition molecules for attacking foreign objects intruding the open circulatory system. BioEssays 23:344–351, 2001. © 2001 John Wiley & Sons, Inc.
Drosophila peripodial cells, more than meets the eye?
Authors: Gibson Matthew C. , Schubiger Gerold 
Published: August 2002

AbstractDrosophila imaginal discs (appendage primordia) have proved invaluable for deciphering cellular and molecular mechanisms of animal development. By combining the accessibility of the discs with the genetic tractability of the fruit fly, researchers have discovered key mechanisms of growth control, pattern formation and long‐range signaling. One of the principal experimental attractions of discs is their anatomical simplicity — they have long been considered to be cellular monolayers. During larval stages, however, the growing discs are 2‐sided sacs composed of a columnar epithelium on one side and a squamous ‘peripodial’ epithelium on the other. Recent studies suggest important roles for peripodial epithelia in processes previously assumed to be confined to columnar cell monolayers. BioEssays 23:691–697, 2001. © 2001 John Wiley & Sons, Inc.
Regulation of meiotic recombination and prophase I progression in mammals
Authors: Cohen Paula E. , Pollard Jeffrey W. 
Published: August 2002

AbstractMeiosis is the process by which diploid germ cells divide to produce haploid gametes for sexual reproduction. The process is highly conserved in eukaryotes, however the recent availability of mouse models for meiotic recombination has revealed surprising regulatory differences between simple unicellular organisms and those with increasingly complex genomes. Moreover, in these higher eukaryotes, the intervention of physiological and sex‐specific factors may also influence how meiotic recombination and progression are monitored and regulated. This review will focus on the recent studies involving mouse mutants for meiosis, and will highlight important differences between traditional model systems for meiosis (such as yeast) and those involving more complex cellular, physiological and genetic criteria. BioEssays 23:996–1009, 2001. © 2001 John Wiley & Sons, Inc.
Effect of interferon‐α on production of reactive oxygen species by human neutrophils
Authors: Koie Takuya , Suzuki Katsuhiko , Shimoyama Tadashi , Umeda Takashi , Nakaji Shigeyuki , Sugawara Kazuo 
Published: August 2002

AbstractIn order to examine that the effects of interferon alpha (IFN‐α) on the production of reactive oxygen species from human neutrophils, we investigated in vitro effects of IFN‐α on neutrophil chemiluminescence responses. Human neutrophils were incubated with 0–1 × 105 IU/mL IFN‐α for 10–60 min just before stimulation with opsonized zymosan and phorbol 12‐myristate 13‐acetate. Luminol‐dependent (LmCL) and lucigenin‐dependent (LgCL) chemiluminescence responses were measured using a Lumi Box H‐1000. The LmCL response was inhibited by pre‐incubation with high concentrations of IFN‐α (more than 1 × 104 IU/mL). In contrast, LgCL response was increased when neutrophils were pre‐incubated with high concentration of IFN‐α. Effects of pre‐incubation of IFN‐α were similar between CL responses stimulated with OZ and PMA. The increase of LgCL might be due to the inhibitory effect of IFN‐α on myeloperoxidase degranulation, in view of the decreased LmCL responses. Copyright © 2001 John Wiley & Sons, Ltd.
Raman signatures of ligand binding and allosteric conformation change in hexameric insulin
Authors: Ferrari Davide , Diers James R. , Bocian David F. , Kaarsholm Niels C. , Dunn Michael F. 
Published: August 2002

AbstractHexameric insulin is an allosteric protein that undergoes transitions between three conformational states (T6, T3R3, and R6). These allosteric states are stabilized by the binding of ligands to the phenolic pockets and by the coordination of anions to the His B10 metal sites. Raman difference (RD) spectroscopy is utilized to examine the binding of phenolic ligands and the binding of thiocyanate, p‐aminobenzoic acid (PABA), or 4‐hydroxy‐3‐nitrobenzoic acid (4H3N) to the allosteric sites of T3R3 and R6. The RD spectroscopic studies show changes in the amide I and III bands for the transition of residues B1–B8 from a meandering coil to an α helix in the T–R transitions and identify the Raman signatures of the structural differences among the T6, T3R3, and R6 states. Evidence of the altered environment caused by the ∼30 Å displacement of phenylalanine (Phe) B1 is clearly seen from changes in the Raman bands of the Phe ring. Raman signatures arising from the coordination of PABA or 4H3N to the histidine (His) B10 Zn(II) sites show these carboxylates give distorted, asymmetric coordination to Zn(II). The RD spectra also reveal the importance of the position and the type of substituents for designing aromatic carboxylates with high affinity for the His B10 metal site. © 2001 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 62: 249–260, 2001
Quantification of random motility and chemotaxis bacterial transport coefficients using individual‐cell and population‐scale assays
Authors: Lewus Paul , Ford Roseanne M. 
Published: August 2002

AbstractA number of individual‐cell and population‐scale assays have been introduced to quantify bacterial motility and chemotaxis. The transport coefficients reported in the literature, however, span several orders of magnitude, making it difficult to ascertain to what degree variations in bacterial species/strain, growth medium, growth and experimental conditions, and experiment type contribute to the reported differences in coefficient values. We quantified the random motility of Escherichia coli AW405 using the capillary assay, stopped‐flow diffusion chamber (SFDC), and tracking microscope. We obtained good agreement for the random motility coefficient between these assays when using the same bacterial strain and consistent growth and experimental conditions. Chemotaxis of E. coli toward the attractant α‐methylaspartate was quantified using the SFDC and capillary assay. Good agreement for the chemotactic sensitivity coefficient between the SFDC and the capillary assay was obtained across a limited attractant concentration range. Three different mathematical models were considered for analyzing capillary assay data to obtain a chemotactic sensitivity coefficient. These models differed by their treatment of the bacterial concentration in the chamber and the attractant concentration at the mouth. Results from our study indicate that the capillary assay, the most commonly used bacterial random motility and chemotaxis assay, can be used to accurately quantify bacterial transport coefficients over a limited range of attractant concentrations, provided experiments are performed carefully and appropriate mathematical models are used to interpret the experimental data. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 292–304, 2001.
Microencapsulation of an anti‐VE–cadherin antibody secreting 1B5 hybridoma cells
Authors: Orive G. , Hernández R. M. , Gascón A. R. , Igartua M. , Rojas A. , Pedraz J. L. 
Published: August 2002

AbstractAccumulating experimental evidence demonstrates that tumor growth and lethality are dependent on angiogenesis. Based on this concept, there is growing interest in the use of antiangiogenesis agents to inhibit tumor expansion. Compelling data implicate vascular endothelium (VE)–cadherin (an endothelium specific protein) as a key factor in the last step of angiogenesis, where the endothelial cells join one to each other and form microtubules (future blood vessels). We propose a novel approach to the inhibition of angiogenesis by immobilizing VE–cadherin‐secreting hybridoma cells in alginate–agarose microcapsules. Hybridoma cells can be protected with biocompatible and semipermeable membranes that permit exit of anti‐VE–cadherin monoclonal antibodies but not entry of cellular immune mediators. Stability studies were performed to select the suitable microcapsule for cell immobilization. Alginate and agarose solid beads coated with poly‐L‐lysine and alginate were chosen according to their stability and diffusional properties. 1B5 hybridoma cells were grown within the microcapsules and secreted anti‐VE–cadherin antibodies during the 9 days of culture, reaching a cumulative concentration of 1.7 μg/mL. This antibody concentration inhibited microtubule formation (87%) in the in vitro angiogenesis Matrigel assay. Moreover, the antiangiogenic effect observed was antibody concentration related. These findings open a new alternative for the inhibition or prevention of angiogenesis and demonstrates the feasibility of using microencapsulated cells as a control‐drug delivery system. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 76: 285–294, 2001.
Precursor‐directed production of erythromycin analogs by Saccharopolyspora erythraea
Authors: Frykman Scott , Leaf Timothy , Carreras Chris , Licari Peter 
Published: August 2002

AbstractDiketide N‐acetylcysteamine (diketide NAC) thioester precursors were fed to 6‐Deoxyerythronolide B synthase (DEBS) ketosynthase‐1 inactivated (KS1°) Saccharopolyspora erythraea strains to produce 13‐substituted erythromycin analogs. This direct feeding process potentially represents a simplified production process over the current analog production system. Titers of these analogs were observed to increase linearly with the diketide concentration up to a precursor‐specific saturation level. However, the rate of product formation was lower and the rate of diketide consumption higher with S. erythraea than was previously observed with a recombinant strain of Streptomyces coelicolor. Several strategies were pursued to address the issue of these high diketide consumption rates: (1) elucidation of the locale of diketide degradation, (2) addition of β‐oxidation inhibitors to the cultures, and (3) addition of a sacrificial diketide enantiomer to occupy putative degradative enzymes. Additionally, repeated addition of diketide to an S. erythraea KS1° culture indicated that the titer of these erythromycin analogs is also currently limited by a shorter production period than observed during erythromycin synthesis by the parent strain. These results indicate potential avenues for expanding the use of this precursor‐directed system from the generation of limited quantities of erythromycin analogs to a large‐scale production system for these compounds. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng. 76: 303–310, 2001.
Preparation of luciferase‐bacterial magnetic particle complex by artificial integration of MagA‐luciferase fusion protein into the bacterial magnetic particle membrane
Authors: Matsunaga Tadashi , Arakaki Atsushi , Takahoko Mikako 
Published: August 2002

AbstractMagA is an iron‐translocating protein found in the membranes of magnetic bacterium. Luciferase‐bacterial magnetic particle (BMP) complexes were prepared by artificially inserting MagA‐luciferase fusion proteins into the membranes of BMPs fromMagnetospirillum magneticumstrain AMB‐1. Fusion proteins were from recombinantEscherichia colimembranes. MagA‐Luc fusion proteins were integrated by sonication in vitro. Successful integration of fusion proteins was confirmed by luciferase luminescence on BMPs. Maximum luminescence was obtained after sonication for 3 min with a solution containing 300 mMNaCl, and is 18 times higher compared with recombinant Luc‐BMPs generated using previously reported gene fusion techniques. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 614–618, 2002; DOI 10.1002/bit.10114
Affinity purification of fibrinogen using a ligand from a peptide library
Authors: Kaufman Deborah B. , Hentsch Marc E. , Baumbach George A. , Buettner Joseph A. , Dadd Christopher A. , Huang Ping Y. , Hammond David J. , Carbonell Ruben G. 
Published: August 2002

AbstractAn affinity resin containing the peptide ligand Phe‐Leu‐Leu‐Val‐Pro‐Leu (FLLVPL) has been developed for the purification of fibrinogen. The ligand was identified by screening a solid‐phase combinatorial peptide library using an immunostaining technique. The specific binding of fibrinogen to the ligand has been characterized by isothermal calorimetry and adsorption isotherms and is dominated by both hydrophobic interactions and ionic interactions with the N‐terminal free amino group. The effective association constant of fibrinogen was substantially higher when the peptide was immobilized on the resin than in solution; moreover, it increased with increasing peptide density, suggesting a cooperative binding effect. A low ionic strength buffer at pH 4 was used successfully to elute adsorbed fibrinogen from the column with high purity, retention of factor XIII crosslinking activity, and minimal, if any, loss of biological function. This general approach to ligand selection and characterization can be used to develop peptide ligands for the affinity purification of diverse proteins on a large scale. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 278–289, 2002.
Coordination of cell growth in cocultures by a genetic proliferation control system
Authors: Schroeder Katharina , Koschmieder Steffen , Ottmann Oliver G. , Hoelzer Dieter , Hauser Hansjörg , Mueller Peter P. 
Published: August 2002

AbstractAdvanced cell culture systems such as organotypic cultures or stem cell expansion often involve cocultivation of two or more different cell types. A typical situation is the use of a feeder cell line that supports survival, growth or controls the differentiation status of primary cells. Unequal proliferation capacities result in unbalanced cell growth, such as the undesired expansion of immortalized cells at the expense of the primary cells. We utilized a genetic regulatory system to coordinate cell growth in cocultures. Proliferation control of a feeder cell line by a recombinant transcription factor was employed to prevent feeder cells from overgrowing cocultured stem cells, thereby avoiding premature media exhaustion. Relevant characteristic cell‐surface proteins present on the parental feeder cell line were preserved. No special equipment was required and cell‐type specific growth could be adjusted even during coculture. When compared to a conventional gamma‐irradiation procedure, genetic proliferation control was superior with respect to ease of use, robustness, cell adherence, morphology and viability. The results demonstrate the applicability of genetic proliferation control to coordinate growth of different cell types in cocultures. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 346–352, 2002.
Cell separation mediated by differential rolling adhesion
Authors: Greenberg Adam W. , Hammer Daniel A. 
Published: August 2002

AbstractRecently, we showed a correlation between the maturity of hematopoietic stem and progenitor cells during development and rolling efficiency on selectins. These findings motivated us to explore a novel separation that exploits differences in selectin‐mediated rolling adhesion between populations of cells. We extend the use of a previously developed cell‐free system to study the separation of populations of sialyl Lewis x (sLex)‐coated microspheres designed to roll with different average velocities on L‐selectin chimeric substrates under well‐defined flow. Results show that a separation that exploits differences in average rolling velocities between cell or microsphere populations is attainable. Excellent recovery and purity values for the slower rolling, or more desirable, populations are obtained and can be estimated from rolling velocity measurements. We also assess the feasibility of a selectin‐mediated separation of adult bone marrow cell populations using previously obtained rolling velocity and rolling flux data for CD34+ and CD34− adult bone marrow cells on L‐selectin substrates. We believe that a cell separation mediated by differential rolling adhesion can be used to enrich populations of hematopoietic stem and progenitor cells from an adult bone marrow cell preparation and that this method possesses several major advantages over existing antibody‐mediated cell‐affinity chromatography technologies. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 111–124, 2001.
Explicit oxygen concentration expression for estimating extant biodegradation kinetics from respirometric experiments
Authors: Goudar Chetan T. , Ellis Timothy G. 
Published: August 2002

AbstractWe present a simple method for estimating extant biodegradation kinetic parameters from oxygen uptake data obtained during respirometric experiments. Specifically, a novel closed‐form solution based on the Lambert W function is presented for the differential equation describing substrate biodegradation based on the Monod equation. Unlike the existing implicit solution, this novel solution is explicit with respect to the substrate concentration and, when coupled with the oxygen uptake equation, results in a simple algebraic expression for dissolved oxygen concentration in respirometric experiments. This new solution provided highly accurate estimates of dissolved oxygen concentrations with accuracy on the order of 10−15 for calculations performed using double precision arithmetic. The applicability of this approach for estimating extant biodegradation kinetic parameters was verified using synthetic dissolved oxygen concentration data that incorporated normally distributed noise to mimic experimental data. A combination of the W function description of oxygen concentration and a nonlinear optimization routine resulted in estimates of the Monod kinetic parameters, μm and Ks, that were close to the actual values, indicating the suitability of this approach for extant kinetic parameter estimation. This approach was subsequently tested on experimental oxygen concentration data obtained during ethylene‐glycol biodegradation in respirometric experiments. The availability of simple algorithms for evaluating the W function makes the new solution easier to compute than current methods that rely on numerical solution of differential or nonlinear equations. The simplicity and accuracy associated with use of the W function to describe oxygen concentration data should make it an attractive approach for estimating extant Monod biodegradation kinetic parameters from respirometric experiments. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 74–81, 2001.