bluuebunny/crossref_metadata_2025_split huggingface dataset:
Luminescence from Lanthanide(3+) Ions in Solution
Authors: Døssing Anders 
Published: March 2005

AbstractAn overview of recent work dealing with luminescence properties in solution of complexes of the lanthanide(3+) ions Nd3+, Eu3+, Tb3+, Er3+ and Yb3+ in which an organic chromophore is attached to the metal centre as a sensitizer is given. The various factors that influence the metal‐centred luminescence lifetime and intensity are discussed and illustrated with own results and recent literature examples. The VIS emitting metal ions Eu3+ and Tb3+ require sensitizers that absorb light in the UV or near UV range whereas VIS absorbing sensitizers can be used for the NIR emitting ions Nd3+, Er3+ and Yb3+. The latter type of complexes is currently of great interest because of potential applications as luminescent markers in biological systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
No effect of hydroxyapatite particles in phagocytosable sizes on implant fixation: An experimental study in dogs
Authors: Rahbek O. , Kold S. , Bendix K. , Overgaard S. , Soballe K. 
Published: March 2005

AbstractThe influence of wear debris on bone healing around orthopedic implants is debated. Hydroxyapatite (HA) particles and polyethylene (PE) particles have been shown to have a negative effect on osteoblast cultures in vitro. The present study investigated the in vivo effects of HA and PE particles on the mechanical fixation and gap healing around experimental HA implants. Nonloaded implants (n = 30) were inserted bilaterally into the proximal tibia of 15 dogs with a 2‐mm gap to the bone. The peri‐implant gap was either (1) empty (n = 6) or filled with (2) hyaluronic acid (n = 8), (3) hyaluronic acid and HA particles (n = 8), or (4) hyaluronic acid and PE particles (n = 8). After 4 weeks, the animals were killed. The implant interface was evaluated by pushout testing until failure and by histomorphometry. Both HA and PE particles were found to be phagocytosed by macrophage‐like cells in the interfacial tissue. HA particles were also integrated in newly formed bone. We found no negative effect of the particulate material on mechanical fixation of the implants or on bone formation around the implants. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res 73A: 150–157, 2005
Anti‐phosphopeptide antibody, P‐STM as a novel tool for detecting mitotic phosphoproteins: Identification of lamins A and C as two major targets
Authors: Tsai I‐Chen , Hsieh Ya‐Ju , Lyu Ping‐Chiang , Yu Jau‐Song 
Published: March 2005

AbstractA polyclonal, phospho‐epitope‐specific antibody (P‐STM) was generated to detect the activated p21‐activated kinase 2 (PAK2), based on the regulatory autophosphorylation site Thr402 of PAK2 [Yu et al., 1998]. In this report, we show that this antibody can also recognize many phosphoproteins in mitotic HeLa and A431 cells. Signal of these phosphoproteins emerged after treating the cells with nocodazole and okadaic acid, and was highly detected in G2‐M phase transition of HeLa cells released from double thymidine block. Immunofluorescence analysis revealed that P‐STM strongly stained HeLa cells at prometaphase and metaphase, but not at interphase and anaphase. Interestingly, this staining pattern was almost identical to that obtained by staining with MPM2, a monoclonal antibody known to react with phosphoproteins in mitotic HeLa cells. However, the phosphoproteins detected by the two antibodies are quite different. Two‐dimensional gel electrophoresis (2DE) and tryptic peptide fingerprint analysis by matrix‐assisted laser desorption/ionization‐time of flight (MALDI‐TOF) mass spectrometry were employed to identify lamins A and C as two of the mitotic cell‐specific phosphoproteins recognized by P‐STM. Lamins A and C immunoprecipitated from nocodazole‐treated cells, but not from untreated cells showed strong reactivity to P‐STM, and this reactivity lost completely after protein phosphatase 2A treatment. In summary, our results show that P‐STM represents a novel tool for detecting mitotic phosphoproteins, which are different from those recognized by MPM2, and that lamins A and C are the two prominent mitotic phosphoproteins detected by P‐STM. J. Cell. Biochem. 94: 967–981, 2005. © 2004 Wiley‐Liss, Inc.
Mechanical modulation of molecular signals which regulate anabolic and catabolic activity in bone tissue
Authors: Judex Stefan , Zhong Nan , Squire Maria E. , Ye Kenny , Donahue Leah‐Rae , Hadjiargyrou Michael , Rubin Clinton T. 
Published: March 2005

AbstractIdentifying the molecular mechanisms that regulate bone's adaptive response to alterations in load bearing may potentiate the discovery of interventions to curb osteoporosis. Adult female mice (BALB/cByJ) were subjected to catabolic (disuse) and anabolic (45 Hz, 0.3g vibration for 10 min/day) signals, and changes in the mRNA levels of thirteen genes were compared to altered indices of bone formation. Age‐matched mice served as controls. Following 4 days of disuse, significant (P = 0.05) decreases in mRNA levels were measured for several genes, including collagen type I (−55%), osteonectin (−44%), osterix (−36%), and MMP‐2 (−36%) all of which, after 21 days, had normalized to control levels. In contrast, expression of several genes in the vibrated group, which failed to show significant changes at 4 days, demonstrated significant increases after 21 days, including inducible nitric oxide synthase (iNOS) (39%, P = 0.07), MMP‐2 (54%), and receptor activator of the nuclear factor kB ligand (RANKL) (32%). Correlations of gene expression patterns across experimental conditions and time points allowed the functional clustering of responsive genes into two distinct groups. Each cluster's specific regulatory role (formation vs. resorption) was reinforced by the 60% suppression of formation rates caused by disuse, and the 55% increase in formation rates stimulated by mechanical signals (P < 0.05). These data confirm the complexity of the bone remodeling process, both in terms of the number of genes involved, their interaction and coordination of resorptive and formative activity, and the temporal sensitivity of the processes. More detailed spatial and temporal correlations between altered mRNA levels and tissue plasticity may further delineate the molecules responsible for the control of bone mass and morphology. J. Cell. Biochem. 94: 982–994, 2005. © 2004 Wiley‐Liss, Inc.
Anti‐adipogenic effect of PDGF is reversed by PKC inhibition
Authors: Artemenko Y. , Gagnon A. , Aubin D. , Sorisky A. 
Published: March 2005

AbstractHealthy adipose tissue function depends on adipogenesis. The capacity to form new adipocytes prevents the emergence of insulin‐resistant hypertrophied adipocytes, as well as the deleterious lipid deposition in muscle, liver, and pancreas. It is therefore important to understand how adipogenesis is modulated. Platelet‐derived growth factor (PDGF) is anti‐adipogenic, but the stage of differentiation that it targets, and the signaling pathways that it triggers, are not defined. We have studied the inhibitory effect of PDGF on murine 3T3‐L1 preadipocyte and human preadipocyte differentiation. There was a significant attenuation in the protein expression of the adipogenic transcription factors, PPARγ and C/EBPα, as well as in the levels of later differentiation markers, including adiponectin, aP2, and fatty acid synthase. PDGF treatment resulted in the persistence of PDGF receptor and PKCα expression, in contrast to the expected downregulation of both proteins that occurs during differentiation. Inactivation of conventional PKC isoforms, by bisindolylmaleimide I or PKC pseudosubstrate M20–28, partially reversed the inhibition of 3T3‐L1 and human preadipocyte differentiation by PDGF, as assessed by fatty acid synthase expression and morphological appearance. © 2005 Wiley‐Liss, Inc.
Influence of oxygen on the proliferation and metabolism of adipose derived adult stem cells
Authors: Wang David W. , Fermor Beverley , Gimble Jeffrey M. , Awad Hani A. , Guilak Farshid 
Published: March 2005

AbstractArticular cartilage is an avascular connective tissue that exhibits little intrinsic capacity for repair. Articular cartilage exists in a reduced oxygen (∼5%) environment in vivo; therefore, oxygen tension may be an important factor that regulates the metabolism of chondrocyte progenitors. A number of recent studies have developed tissue engineering approaches for promoting cartilage repair using undifferentiated progenitor cells seeded on biomaterial scaffolds, but little is known about how oxygen might influence these engineered tissues. Human adipose‐derived adult stem (hADAS) cells isolated from the stroma of subcutaneous fat were suspended in alginate beads and cultured in control or chondrogenic media in either low oxygen (5%) or atmospheric oxygen tension (20%) for up to 14 days. Under chondrogenic conditions, low oxygen tension significantly inhibited the proliferation of hADAS cells, but induced a two‐fold increase in the rate of protein synthesis and a three‐fold increase in total collagen synthesis. Low oxygen tension also increased glycosaminoglycan synthesis at certain timepoints. Immunohistochemical analysis showed significant production of cartilage‐associated matrix molecules, including collagen type II and chondroitin‐4‐sulfate. These findings suggest oxygen tension may play an important role in regulating the proliferation and metabolism of hADAS cells as they undergo chondrogenesis, and the exogenous control of oxygen tension may provide a means of increasing the overall accumulation of matrix macromolecules in tissue‐engineered cartilage. © 2005 Wiley‐Liss, Inc.
Electromagnetic fields at mobile phone frequency induce apoptosis and inactivation of the multi‐chaperone complex in human epidermoid cancer cells
Authors: Caraglia Michele , Marra Monica , Mancinelli Fabrizio , D'ambrosio Guglielmo , Massa Rita , Giordano Antonio , Budillon Alfredo , Abbruzzese Alberto , Bismuto Ettore 
Published: March 2005

AbstractThe exposure to non‐thermal microwave electromagnetic field (MW‐EMF) at 1.95 MHz, a frequency used in mobile communication, affects the refolding kinetics of eukaryotic proteins (Mancinelli et al., 2004). On these basis we have evaluated the in vivo effect of MW‐EMF in human epidermoid cancer KB cells. We have found that MW‐EMF induces time‐dependent apoptosis (45% after 3 h) that is paralleled by an about 2.5‐fold decrease of the expression of ras and Raf‐1 and of the activity of ras and Erk‐1/2. Although also the expression of Akt was reduced its activity was unchanged likely as a consequence of the increased expression of its upstream activator PI3K. In the same experimental conditions an about 2.5‐fold increase of the ubiquitination of ras and Raf‐1 was also found and the addition for 12 h of proteasome inhibitor lactacystin at 10 μM caused an accumulation of the ubiquitinated isoforms of ras and Raf‐1 and counteracted the effects of MW‐EMF on ras and Raf‐1 expression suggesting an increased proteasome‐dependent degradation induced by MW‐EMF. The exposure of KB cells to MW‐EMF induced a differential activation of stress‐dependent pathway with an increase of JNK‐1 activity and HSP70 and 27 expression and with a reduction of p38 kinase activity and HSP90 expression. The overexpression of HSP90 induced by transfection of KB cells with a plasmid encoding for the factor completely antagonized the apoptosis and the inactivation of the ras → Erk‐dependent survival signal induced by MW‐EMF. Conversely, the inhibition of Erk activity induced by 12 h exposure to 10 mM Mek‐1 inhibitor U0126 antagonized the effects induced by HSP90 transfection on apoptosis caused by MW‐EMF. In conclusion, these results demonstrate for the first time that MW‐EMF induces apoptosis through the inactivation of the ras → Erk survival signaling due to enhanced degradation of ras and Raf‐1 determined by decreased expression of HSP90 and the consequent increase of proteasome dependent degradation. © 2005 Wiley‐Liss, Inc.
Experimental and mathematical study of the influence of growth factors on the growth kinetics of adult human articular chondrocytes
Authors: Barbero Andrea , Palumberi Viviana , Wagner Barbara , Sader Robert , Grote Marcus J. , Martin Ivan 
Published: March 2005

AbstractThis study aimed at determining how kinetic parameters of adult human articular chondrocytes (AHAC) growth are modulated by the growth factor combination TGFβ1, FGF‐2, and PDGF BB (TFP), recently shown to stimulate AHAC proliferation. AHAC, isolated from cartilage biopsies of three individuals, were cultured in medium without (CTR) or with TFP. For growth curves, AHAC were seeded at 1,000 cells/cm2 and cultured for 12 days, with cell numbers measured fluorimetrically in the same wells every 12 h. For microcolony tests, AHAC were seeded at 2.5 cells/cm2 and cultured for 6 days, with cell numbers determined for each microcolony by phase contrast microscopy every 8 h. A mathematical model combining delay and logistic equations was developed to capture the growth kinetic parameters and to enable the description of the complete growth process of the cell culture. As compared to CTR medium, the presence of TFP increased the number of cells/well starting from the fifth day of culture, and a four‐fold larger cell number was reached at confluency. For single microcolonies, TFP reduced the time for the first cell division by 26.6%, the time for subsequent cell divisions (generation time) by 16.8%, and the percentage of quiescent cells (Qc) by 42.5%. The mathematical model fitted well the experimental data of the growth kinetic. Finally, using both microcolony tests and the mathematical model, we determined that prolonged cell expansion induces an enrichment of AHAC with shorter first division time, but not of those with shorter generation time. © 2005 Wiley‐Liss, Inc.
Pregnancy‐associated plasma protein‐A proteolytic activity in rat vertebral cell cultures: Stimulation by dexamethasone–a potential mechanism for glucocorticoid regulation of osteoprogenitor proliferation and differentiation
Authors: Jia Dan , Heersche Johan N.M. 
Published: March 2005

AbstractGlucocorticoids (GCs) at physiological concentrations stimulate osteoprogenitor proliferation and differentiation in rat bone cell populations, and this is mediated in part by an increased response to insulin‐like growth factors (IGFs). Since IGF binding proteins (IGFBPs) modulate IGF actions, we evaluated whether the increased IGF responsiveness might be associated with decreased inhibitory IGFBP‐4 peptide levels. Rat vertebral cells were cultured for up to 20 days with or without dexamethasone (Dex). Cell layer proteins were extracted at day 6, 8, 14, and 20, conditioned media (CM) collected at day 8, 14, and 20, and total RNA isolated at day 14 and 20 of culture. Western blotting showed that cell layer IGFBP‐4 levels were lower, while IGFBP‐4 protease activity in CM was higher, in Dex‐treated cultures. Addition of pregnancy‐associated plasma protein‐A (PAPP‐A) antibody to CM abrogated IGFBP‐4 proteolysis. PAPP‐A mRNA levels were the same in control and Dex‐treated cultures as evaluated by RT‐PCR. Our data demonstrate that activity of the IGFBP‐4 protease, PAPP‐A, in rat bone cell cultures is increased by Dex via post‐transcriptional mechanisms. Since IGFBP‐4 mRNA levels in Dex‐treated cultures were the same as in controls at day 8, slightly lower than in controls at day 14, and higher than in controls at day 20 as shown previously, the decreased IGFBP‐4 peptide levels in Dex‐treated cultures likely result from increased IGFBP‐4 proteolysis by the elevated PAPP‐A enzymatic activity. Our findings underscore a novel mechanism whereby GCs increase IGF responses in rat bone cells via PAPP‐A‐induced IGFBP‐4 proteolysis. © 2005 Wiley‐Liss, Inc.
Removal of zinc from dilute aqueous solutions by galvanochemical treatment
Authors: Zouboulis AI , Prochaska CA , Solozhenkin PM 
Published: March 2005

AbstractThe possibility of zinc removal, a common toxic metal, from simulated liquid effluents by the application of a novel treatment method, termed galvanochemical, was investigated. The galvanochemical process is considered as a simple, economic, friendly to the environment, method, which does not create harmful end‐products. Synthetic wastewaters were examined, these contained concentrations of zinc commonly found in real wastewaters from small‐to‐medium size industrial units, such as metal‐plating or metal‐treatment plants. These liquid wastes pose an important environmental problem, due to the content of heavy metals. The optimization of the main operating parameters was the objective of the study. The galvanic pair scrap ratio iron:coke was used for these investigations. It was found that the use of the galvanic pair mixture of 80 g dm−3 (weight per solution volume ratio), agitated at 160 rpm for 5 h, removed more than 90% of zinc from the initial solution, containing initially 50 mg dm−3 of zinc. The scanning electron microscopy/energy disperse spectrometry (SEM/EDS) analysis performed on the products showed that zinc was adsorbed onto the coke to a small extent and that the zinc removal was mainly based on the adsorption of zinc onto the surface of active iron oxides formed as a result of galvanochemical reactions. Copyright © 2005 Society of Chemical Industry
Understanding the implications of empirical work on corporate growth rates
Authors: Geroski P. A. 
Published: March 2005

AbstractThis paper builds on the empirical literature on corporate growth rates — which suggests that corporate growth rates are very nearly random — and asks whether this empirical work is consistent with standard theories of the firm. We examine both static and dynamic optimizing models of firm output choice, before moving on to examine production functions modelling of corporate learning, models of R&D competition and diversification. In all cases, it seems clear that random corporate growth rates are more or less exactly what one would expect these models to predict. However, the literature on Penrose effects — dynamic managerial limitations to growth — and corporate competencies are not easy to reconcile with random corporate growth rates. Copyright © 2005 John Wiley & Sons, Ltd.
Problem‐solving and competence creation in the early development of new firms
Authors: Hugo Oliver , Garnsey Elizabeth 
Published: March 2005

AbstractThis paper aims to identify how entrepreneurial responses to ‘barriers’ can give rise to opportunities for new firms. The poor predictive record of studies analysing success attributes and favourable initial factors as determinants of new firm growth reflects the diversity of entrepreneurial responses to problems of growth, as illustrated by three case studies of new companies which were able to overcome adverse initial conditions despite the lack of early ‘success attributes’. They did so by finding alternative opportunities and by achieving resource economy, resource leverage and resource creation, aided by strategic relationships formed with other players. Spurred by the problems they encounter, entrepreneurial firms revise their business conjecture and engage in innovative activities, their business model evolving through trial and error. Creative responses to unexpected developments by entrepreneurial decision makers have implications for research methodology and business support. Copyright © 2005 John Wiley & Sons, Ltd.
Edith Penrose's legacy to the resource‐based view
Authors: Lockett Andy 
Published: March 2005

AbstractIn this paper I argue that Edith Penrose's work anticipated the modern approach to strategy in general, and the RBV in particular. Building on the central tenets of Penrose's arguments—that firms are heterogeneous, which is the result of their path dependency—the paper demonstrates how her writings can be used to explain the latest developments of the RBV. Furthermore, the paper argues that many of the insights scholars require to take the RBV forward are still available to those willing to re‐visit her writings. Simply stated: Her legacy endures. Copyright © 2005 John Wiley & Sons, Ltd.
Edith Penrose, organisational economics and business strategy: an assessment and extension
Authors: Pitelis Christos 
Published: March 2005

AbstractThe aim of this paper is to expound Penrose's contribution to the theory of the firm, and examine the contribution of her thinking to economics and business strategy, as well as to discuss some limitations and provide some generalizations of Penrose's work. We also discuss implications for managerial practice and public policy. We claim that Penrose's contribution was seminal. In recognizing the significance of organization to generate new knowledge she went well beyond the bounds of even her own agenda; from a theory of the growth of firms, to a theory of the generation of organizational knowledge and beyond. Copyright © 2005 John Wiley & Sons, Ltd.
A logistics scheduling model: Inventory cost reduction by batching
Authors: Qi Xiangtong 
Published: March 2005

AbstractLogistics scheduling refers to the problems where the decisions of job scheduling and transportation are integrated in a single framework. In this paper, we discuss a logistics scheduling model where the raw material is delivered to the shop in batches. By making the batching and scheduling decisions simultaneously, the total inventory and batch setup cost can be reduced. We study different models on this issue, present complexity analysis and optimal algorithms, and conduct computational experiments. Some managerial insights are observed. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.
Non‐iterative and exact method for constraining particles in a linear geometry
Authors: Tapia‐McClung Horacio , Grønbech‐Jensen Niels 
Published: March 2005

AbstractWe present a practical numerical method for evaluating the Lagrange multipliers necessary for maintaining a constrained linear geometry of particles in dynamical simulations. The method involves no iterations and is limited in accuracy only by the numerical methods for solving small systems of linear equations. As a result of the non‐iterative and exact (within numerical accuracy) nature of the procedure, there is no drift in the constrained geometry, and the method is therefore readily applied to molecular dynamics simulations of, for example, rigid linear molecules or materials of non‐spherical grains. We illustrate the approach through implementation in the commonly used second‐order velocity‐explicit Verlet method. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 911‐916, 2005
Dendritic cells generated from patients with androgen‐independent prostate cancer are not impaired in migration and T‐cell stimulation
Authors: Waeckerle‐Men Ying , Allmen Edith Uetz‐von , von Moos Roger , Classon Brendan J. , Scandella Elke , Schmid Hans‐Peter , Ludewig Burkhard , Groettrup Marcus , Gillessen Silke 
Published: March 2005

AbstractBACKGROUNDDendritic cell (DC)‐based vaccination has been investigated as immunotherapy for several types of cancer. A potential drawback to vaccination with autologous monocyte‐derived DCs (MoDCs) could be that MoDCs from patients are functionally impaired. In case of androgen‐independent prostate cancer (CaP), the cancer itself, diverse prior therapies, and the hormone manipulation may affect the immune system.METHODSMoDCs from patients suffering from androgen‐independent CaP were generated according to a clinically applicable protocol to evaluate the phenotype, maturation capacity, migration, and T‐cell stimulation of these cells compared with those generated from tumor‐free donors.RESULTSMoDCs generated from CaP patients could be fully matured and efficiently migrated towards the chemokine CCL21. They had a strong potency to activate allogeneic CD4+ and CD8+ T‐cells and to present antigens to specific CTL.CONCLUSIONSOur data suggest that MoDCs from patients with androgen‐independent CaP are functionally intact and hence qualify as cellular vaccines for immunotherapy of advanced stage CaP. © 2005 Wiley‐Liss, Inc.