bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of a non‐functional p53 affects the sensitivity of cancer cells to gemcitabine
Authors: Galmarini Carlos María , Clarke Marilyn L. , Falette Nicole , Puisieux Alain , Mackey John R. , Dumontet Charles
Published: August 2002

Gemcitabine is a relatively new agent with promising activity in solid tumors. Few data are available regarding mechanisms of resistance to gemcitabine downstream from the drug‐target interaction. The present study was performed to gain insight into the role of p53 status on the cytotoxicity of gemcitabine on cancer cells. Drug sensitivity, drug metabolism, cell kinetics and drug‐induced apoptosis were compared in 2 lines derived from the mammary adenocarcinoma MCF‐7: the wildtype p53 (wt‐p53) containing MN‐1 cell line and, the MDD2 line containing a dominant negative variant of the p53 protein (mut‐p53). The MDD2 cell line was significantly more resistant to gemcitabine cytotoxicity than the MN‐1 cell line. The resistant phenotype could not be attributed to a defective gemcitabine activation/degradation pathway or altered levels of expression of intracellular targets. Although both cell lines exhibited p53 accumulation, MN‐1 but not MDD2 cells, displayed p21WAF1 induction after exposure to gemcitabine. Gemcitabine induced an S‐phase arrest in both cell lines. A more pronounced block in G1 phase, however, was observed in MN1 cells. Exposure to gemcitabine induced a higher degree of apoptosis in MN‐1 than in MDD2 cells. This corresponded with suppression of Bcl‐2 and Bcl‐X/L expression in wt‐p53 cells exposed to gemcitabine whereas Bcl‐2 levels remained stable and Bcl‐X/L levels increased in mut‐p53 cells exposed to gemcitabine. We conclude that the p53 status of cancer cells influences their sensitivity to gemcitabine cytotoxicity. Our evidence suggests that loss of p53 function leads to loss of cell cycle control and alterations in the apoptotic cascade, conferring resistance to gemcitabine in cancer cell lines displaying a mut‐p53. © 2001 Wiley‐Liss, Inc.
The ECB monetary policy strategy and the money market
Authors: Gaspar Vítor , Perez‐Quiros Gabriel , Sicilia Jorge
Published: August 2002

This paper aims at contributing to the understanding of how the ECB conducts monetary policy as seen from a money market perspective. More specifically it covers two different issues. First, it looks at the ‘learning period’ for banks since the Eurosystem started implementing the single monetary policy. It shows that during the first three weeks of 1999 the narrow corridor in place during this period was effective in limiting daily volatility of the money market overnight rates. In addition, the behaviour of banks and market rates during this period provides evidence that learning was taking place. Second, it looks at how well money market participants have anticipated the monetary policy decisions taken by the ECB. To do so, the paper analyses whether the announcements of monetary policy decisions to maintain or change interest rates impact on the stochastic behaviour of interest rates. Looking at the EONIA rates within the reserve maintenance periods, we find that the announcement of monetary policy decisions does not change significantly the level or volatility of overnight rates. Copyright © 2001 John Wiley & Sons, Ltd.
Rrepresentations of trauma in infancy: Clinical and theoretical implications for the understanding of early memory
Authors: Gaensbauer Theodore J.
Published: August 2002

Understanding the nature of the infant's internal experience is a crucial prerequisite for delineating the developmental effects of an early trauma. In addition, to the extent that internal representations of a trauma can be traced over time, traumatic experiences present unique opportunities for the study of early memory. This article will describe case vignettes of children who experienced a trauma in the preverbal period and who evidenced forms of memory of their trauma at subsequent points in time. In conjunction with the clinical material, developmental research bearing on the types of early memories described will be discussed. The clinical data, reinforced by research findings, indicate that preverbal children, even in the first year of life, can establish and retain some form of internal representation of a traumatic event over significant periods of time. The specificity and enduring nature of the internal representations suggest that specific therapeutic interventions over and above general comforting will be required if an infant is to maximally recover from a trauma. The clinical findings have relevance for a number of issues currently under debate in the area of infant memory, including the role of reminders in memory retention, the nature of early memory systems, and the development of autobiographical memory. ©2002 Michigan Association for Infant Mental Health.
Estimating economic relationships subject to firm‐ and time‐varying equality and inequality constraints
Authors: O'Donnell Christopher J. , Rambaldi Alicia N. , Doran Howard E.
Published: August 2002

Applied econometricians often fail to impose economic regularity constraints in the exact form economic theory prescribes. We show how the Singular Value Decomposition (SVD) Theorem and Markov Chain Monte Carlo (MCMC) methods can be used to rigorously impose time‐ and firm‐varying equality and inequality constraints. To illustrate the technique we estimate a system of translog input demand functions subject to all the constraints implied by economic theory, including observation‐varying symmetry and concavity constraints. Results are presented in the form of characteristics of the estimated posterior distributions of functions of the parameters. Copyright © 2001 John Wiley & Sons, Ltd.
Possible androgenic/anti‐androgenic activity of the insecticide fenitrothion
Authors: Sohoni P. , Lefevre P. A. , Ashby J. , Sumpter J. P.
Published: August 2002

To date, within the field of endocrine disruption, much focus has been placed on chemicals that mimic oestrogens (so‐called xenoestrogens), and the number of such chemicals apparently detected continues to grow steadily. Less effort has been expended on investigating chemicals that mimic, or antagonize, other hormones. Nevertheless, a number of chemicals have been reported to have a weak affinity for the androgen receptor, all of which have, to date, been found to have anti‐androgenic activity in vivo. In this report, we present evidence that the insecticide fenitrothion can interact with the androgen, but not with the oestrogen, receptor. Using recombinant yeast expressing the human androgen receptor, we found that fenitrothion behaved as an androgen agonist in vitro when tested alone, and that it could antagonize the androgen DHT when both chemicals competed for the androgen receptor in vitro. In vivo studies using both intact and castrated male rats showed no conclusive androgenic or anti‐androgenic responses. Changes in organ weights suggestive of anti‐androgenic effects were mitigated against by the reduced body weights of fenitrothion‐treated rats. The toxicity of the compound precluded the use of higher dose levels to substantiate any tentative findings. Interestingly, fenitrothion (and related insecticides) is structurally similar to flutamide, an anti‐androgen used clinically that gives clearly positive responses in both intact and castrated rats. Copyright © 2001 John Wiley & Sons, Ltd.
Theoretical analysis of adsorption thermodynamics for hydrophobic peptide residues on SAM surfaces of varying functionality
Authors: Latour Robert A. , Rini Christopher J.
Published: August 2002

At a fundamental level, protein adsorption to a synthetic surface must be strongly influenced by the interaction between the peptide residues presented by the protein's surface (primary protein structure) and the functional groups presented by the synthetic surface. In this study, semi‐empirical molecular modeling was used along with experimental wetting data to theoretically approach protein adsorption at this primary structural level. Changes in enthalpy, entropy, and Gibbs free energy were calculated as a function of residue–surface separation distance for the adsorption of individual hydrophobic peptide residues (valine, leucine, phenylalanine) on alkanethiol self‐assembled monolayers on gold [Au−S(CH2)15−X; X = CH3, OH, NH3+, COO−]. The results predict that the adsorption of each type of hydrophobic residue is energetically favorable and entropy dominated on a methyl‐terminated hydrophobic surface, energetically unfavorable and enthalpy dominated on a hydroxyl‐terminated neutral hydrophilic surface, and very slightly favorable to unfavorable and enthalpy dominated on charged surfaces. These theoretical results provide a basis for understanding some of the fundamental effects governing protein adsorption to synthetic surfaces. This level of understanding is needed for the proactive design of surfaces to control protein adsorption and subsequent cellular response for both implant and tissue engineering applications. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 564–577, 2002
Evaluation of nanostructured carbonated hydroxyapatite coatings formed by a hybrid process of plasma spraying and hydrothermal synthesis
Authors: Han Yong , Xu Kewei , Montay Gillaume , Fu Tao , Lu Jian
Published: August 2002

Carbonated hydroxyapatite (CHA) coatings on a titanium alloy were prepared by hydrothermal synthesis of precursors plasma‐sprayed with brushite as a raw powder. The structures, residual stresses, and bond strengths of the precursors and CHA coatings were investigated. The results showed that the sprayed precursors consisted of β‐Ca2P2O7, α‐Ca3(PO4)2, and CaHPO4, whereas the CHA coatings exhibited a unique phase construction, nanostructured and needlelike crystals, and a fairly low tensile residual stress. The bond strength of a CHA coating 200 μm thick was 15 MPa, equivalent to that of a plasma‐sprayed hydroxyapatite (HA) coating. The evaluation of the CHA coatings was performed together with that of plasma‐sprayed HA coatings immersed in distilled water. The dissolution and bond‐strength degradation of the CHA coatings were much lower than those of the plasma‐sprayed HA coatings. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 511–516, 2002
Mechanical properties and osteoconductivity of new bioactive composites consisting of partially crystallized glass beads and poly(methyl methacrylate)
Authors: Shinzato Shuichi , Nakamura Takashi , Ando Keiji , Kokubo Tadashi , Kitamura Yoshiro
Published: August 2002

New bioactive composites consisting of partially crystallized glass beads as inorganic fillers and poly(methyl methacrylate) (PMMA) as an organic matrix were developed. Two kinds of partially crystallized glass beads, designated Cry820 and Cry850, were newly prepared by the heating of MgO–CaO–SiO2–P2O5 glass at 820 and 850°C, respectively. The glass beads were mixed with PMMA to form two new composites designated Cry820C and Cry850C, respectively. The goal of this study was to produce a highly osteoconductive and mechanically strong composite cement with these new fillers. A previously reported composite cement designated AWC, which was composed of apatite‐ and wollastonite‐containing glass ceramic (AW‐GC) as a powder filler and the same PMMA polymer used in the new composites, was used as a reference material. The quantity of filler added to each composite was 70 wt %. The bending strength of Cry820C was significantly higher than that of Cry850C. Composites were packed into intramedullary canals of rat tibiae to evaluate their osteoconductivity, as determined by an affinity index. The affinity index, which equaled the length of bone in direct contact with the composite surface expressed as a percentage of the total length of the composite surface, was calculated for each composite. The rats were euthanized at 4, 8, and 25 weeks after implantation. At each time interval studied, Cry820C showed a significantly higher affinity index than AWC up to 25 weeks after implantation. Cry850C showed a significantly higher affinity index than AWC up to 8 weeks and a higher affinity index than AWC at 25 weeks, although the difference was not significant. The values for each composite increased significantly with time up to 25 weeks. Our study revealed that the higher osteoconductivity of the new composites was due to the larger quantity of the glassy phase of the crystallized glass beads at the composite surface and the lower solubility of the PMMA powder to methyl methacrylate monomer. In addition, the spherical shape of the crystallized glass beads gave the new composites strong enough mechanical properties to be useful under weight‐bearing conditions. The new composites show promise as alternatives, with improved properties, to conventional PMMA bone cement. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 556–563, 2002
Polyethylene wear characteristics in vivo and in a knee stimulator
Authors: Beaulé P. E. , Campbell P. A. , Walker P. S. , Schmalzried T. P. , Dorey F. J. , Blunn G. W. , Bell C. J. , Yahia L'H. , Amstutz H. C.
Published: August 2002

Validation of a wear simulator requires that the device produce a similar type and amount of wear and particles of a comparable morphology as occurs clinically. Using techniques previously established to compare polyethylene particles from hip simulators to those from retrieved tissues, particles isolated from six revised posterior stabilized knee replacements were characterized and compared to particles generated from the same knee design worn in a knee simulator. The particles produced in the knee simulator were of comparable size but had less variability in their form factor compared to the particles produced in vivo. Comparable wear features were seen on the articulating surfaces in both groups. These results indicate that this knee joint simulator is able to reproduce a baseline type of wear that is similar to that in vivo and should encourage further use of this device to better understand knee component wear and function. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 411–419, 2002; DOI 10.1002/jbm.10139
Adhesion barriers of carboxymethylcellulose and polyethylene oxide composite gels
Authors: Liu Lin‐Shu , Berg Richard A.
Published: August 2002

Composite gels and films of CMC and PEO have been used to separate healing tissues and have been demonstrated to reduce postsurgical adhesions in animal models of adhesion formation. Gels of CMC/PEO were studied here to elucidate the mechanism by which the combination of PEO with CMC is effective in reducing adhesions between tissues. CMC and PEO were demonstrated to undergo micro phase separation to form a two‐phase system. Protein partitioning was measured in this system for albumin, fibrinogen, and gamma globulin. All of these proteins were found to partition preferentially into the CMC phase. When gels of CMC and PEO were examined for tissue adherence, the addition of PEO reduced the adherence of CMC to tissues. To further investigate the effects of PEO on tissue adherence of the gel, the extent of thrombus formation of citrated blood initiated by calcium chloride in CMC/PEO gels was measured in vitro. The extent of thrombus formation by CMC was reduced proportionally to the content of PEO in gels of CMC/PEO. A model was developed to explain how CMC and PEO contribute to the effectiveness of CMC/PEO gels that form a barrier between healing tissues to reduce postsurgical adhesions. In an open system PEO is released from the gel faster than CMC is dissolved, resulting in a shell structure with CMC coated by PEO. The PEO‐rich outer layer functions to inhibit protein deposition and thrombus formation. The CMC‐rich layer functions to anchor the gel to the tissue surface. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 326–332, 2002
Bone morphogenetic protein 3b expressing reindeer antler
Authors: Kapanen A. , Ryhänen J. , Birr E. , Väänänen H. K. , Tuukkanen J.
Published: August 2002

A cDNA sequence of bone morphogenetic protein 3b (BMP‐3b) of reindeer antler was produced with degenerative homology primers in polymerase chain reaction (PCR). An in situ hybridization study of BMP‐3b mRNA in 1‐month‐old antler showed expression in most differentiated cells in the antler center. In addition, the bone‐inductive capacity of the reindeer antler matrix was evaluated. Decalcified and powdered antler matrix of different stages of antler maturity was implanted in gelatin capsules under the rat dorsal muscle fascia for two implantation periods: 3 and 8 weeks. Allogenic matrix prepared from rat long bones was used as a positive control implant. Heterotopic ossification was evaluated histomorphometrically and densitometrically. Allogenic bone matrix induced rapid osteogenesis and mineral accumulation. Both endochondral and intramembranous ossification was evident, endochondral ossification being the dominant form. Mineral density in the induced ossicle was 115 ± 48 mg/cm3 as early as at 3 weeks and 350 ± 69 mg/cm3 at 8 weeks. The proportional areas of von Kossa‐stained mineral were 3.67 ± 2.1% and 11.6 ± 0.07%, respectively. The antler preparations induced mineralization, but significantly less than the allogenic bone matrix. At 8 weeks, mineral density was significantly lower in the cast antler preparation than in the allogenic implants. The morphology of the mineralized areas of the antler preparations showed no ossification. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 78–83, 2002
Metabolic heat production as a measure of macrophage response to particles from orthopedic implant materials
Authors: Charlebois S. J. , Daniels A. U. , Smith R. A.
Published: August 2002

An in vitro method to gauge metabolic heat response of macrophages (MØ) to particulates is described. Whereas the majority of work cited relies on chemical analysis to assess MØ response to particles, we have used isothermal microcalorimetry (IMC) for direct continuous measurement of metabolic heat production to gauge the response. IMC is a screening method, in that it ensures that no energy‐consuming phagocytic response goes undetected, and that the aggregate metabolic magnitude of the responses is determined. A four‐well IMC was used in all microcalorimetric measurements. To accommodate “zero‐time” monitoring of the interaction of particles and cells, a set of identical test chambers was constructed for use in the IMC. MØs were injected from outside the IMC onto particles contained in collagen or gelatin on glass coverslips at the bottom of each chamber. IMC runs were performed using MØs only, MØs and lipopolysaccharide (LPS) positive control, and MØs and clean or LPS‐bound particles of either high‐density polyethylene (HDPE) or cobalt–chrome alloy (CoCr). Total heat produced by the negative controls (MØs alone) was lower than for MØ exposure to LPS or particles. The trend was a higher response for LPS‐bound HDPE compared with clean HDPE particles, though not significant. In conclusion, our results have shown that IMC can be used to detect the heat associated with the phagocytosis of particulate materials by MØs in vitro. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 166–175, 2002
Fabrication of poly(α‐hydroxy acid) foam scaffolds using multiple solvent systems
Authors: Hu Yunhua , Grainger David W. , Winn Shelley R. , Hollinger Jeffrey O.
Published: August 2002

The present studies describe the fabrication and characterization of highly porous and interconnected poly(α‐hydroxy acid) foam scaffolds produced using a phase separation multisolvent system, followed by a sublimation process. Fabrication parameters, including solvent composition, polymer concentration, freezing temperature, polymer type, and polymer molecular weight, were optimized to produce the desired foam microstructure. Analyses of selected samples with scanning electron microscopic images and mercury intrusion porosimetry indicated polymer foams with pore size ranges of 100–350 μm, a porosity >90%, and an interconnecting open‐pore foam structure. Scaffold degradation profiles varied according to the type and molecular weight of the polymers. Cytocompatibility assays demonstrated that the preferred foam structures were nontoxic and osteoprecursor cells seeded into the scaffolds exhibited the ability to attach, propagate, and differentiate into a calcified structure. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 563–572, 2002
Heparin‐like polymer improved healing of gastric and colic ulceration
Authors: Meddahi Anne , Alexakis Catherine , Papy Dulce , Caruelle Jean‐Pierre , Barritault Denis
Published: August 2002

A family of chemically substituted biopolymers has been developed to protect and stabilize heparin binding growth factors and was shown to enhance tissue repair in various in vivo models. One of these compounds, a dextran derivative named RGTA11, was tested for its ability to treat acute gastritis and colic ulceration models induced by ethanol and acid. RGTA was not efficient in reducing nor in protecting against gastric acidic secretion compared to EGF. Ethanol gastritis measured by the alteration score of the injured mucosa was reduced by 56% with the oral administration of RGTA at doses of 100 μg/kg (p < 0.01). A similar effect was obtained by PGE2 at a similar dose. Alterations of the colic mucosa were reduced after 72 h by 75% after oral administration of RGTA11. RGTA presents both anti‐inflammatory and tissue repair activities mediated by growth factor protection. These two properties would be beneficial for digestive ulcer treatment. The results presented here provide evidence for these effects. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 497–501, 2002; DOI 10.1002/jbm.1293
Support vector machines for prediction of protein subcellular location by incorporating quasi‐sequence‐order effect
Authors: Cai Yu‐Dong , Liu Xiao‐Jun , Xu Xue‐biao , Chou Kuo‐Chen
Published: August 2002

Support Vector Machine (SVM), which is one class of learning machines, was applied to predict the subcellular location of proteins by incorporating the quasi‐sequence‐order effect (Chou [2000] Biochem. Biophys. Res. Commun. 278:477–483). In this study, the proteins are classified into the following 12 groups: (1) chloroplast, (2) cytoplasm, (3) cytoskeleton, (4) endoplasmic reticulum, (5) extracellular, (6) Golgi apparatus, (7) lysosome, (8) mitochondria, (9) nucleus, (10) peroxisome, (11) plasma membrane, and (12) vacuole, which account for most organelles and subcellular compartments in an animal or plant cell. Examinations for self‐consistency and jackknife testing of the SVMs method were conducted for three sets consisting of 1,911, 2,044, and 2,191 proteins. The correct rates for self‐consistency and the jackknife test values achieved with these protein sets were 94 and 83% for 1,911 proteins, 92 and 78% for 2,044 proteins, and 89 and 75% for 2,191 proteins, respectively. Furthermore, tests for correct prediction rates were undertaken with three independent testing datasets containing 2,148 proteins, 2,417 proteins, and 2,494 proteins producing values of 84, 77, and 74%, respectively. J. Cell. Biochem. 84: 343–348, 2002. © 2001 Wiley‐Liss, Inc.
Relaxin activates the MAP kinase pathway in human endometrial stromal cells
Authors: Zhang Qiang , Liu Shu‐Hui , Erikson Mark , Lewis Martyn , Unemori Elaine
Published: August 2002

The reproductive hormone, relaxin, is structurally similar to insulin and insulin‐like growth factor (IGF). Although a number of cellular responses to relaxin have been described, intracellular signaling mechanisms that link relaxin receptor engagement to alterations in gene expression remain uncharacterized. In the present study, relaxin treatment of a well‐characterized target, human endometrial stromal cells, resulted in rapid activation of p42/44 mitogen‐activated protein (MAP) kinase, as well as of MAPK (or ERK) kinase (MEK). Using a selective chemical inhibitor of MEK, it was further demonstrated that MEK phosphorylation is critical for relaxin‐induced MAP kinase activation. Relaxin treatment also induced MAP kinase activation in THP‐1 monocytic cells and in human smooth muscle cells, indicating that it may be a major signaling transducer utilized by the relaxin receptor. In contrast to insulin or IGF‐1, relaxin did not trigger the PI 3‐kinase/Akt pathway, perhaps accounting in part for relaxin's unique biological profile. Relaxin was also found to cause activation of the transcription factor CREB, a substrate of the MAP kinase pathway. Finally, activation of the MAP kinase pathway was shown to be essential for optimal stimulation of expression of the gene for vascular endothelial growth factor. J. Cell. Biochem. 85: 536–544, 2002. © 2002 Wiley‐Liss, Inc.
Human endothelial cells grow poorly on vitronectin: Role of PAI‐1
Authors: Underwood P. Anne , Bean Penny A. , Cubeddu Liza
Published: August 2002

The cell adhesive protein vitronectin is a common component of interstitial extracellular matrix and circulates in plasma. It competes effectively with other plasma proteins to adsorb to certain biomaterial surfaces, and is likely to represent an important cell adhesion mediator on the luminal surface of vascular grafts. It is also found associated with certain vascular pathologies. We have shown previously that human endothelial cells grow poorly on a vitronectin surface compared with other extracellular matrix molecules. In this paper we show that endothelial cells seeded on vitronectin and fibronectin produced substantially different profiles of extracellular matrix molecules. The most outstanding difference was in the amount of matrix‐localised plasminogen activator‐inhibitor‐1 which was high on vitronectin and negligible on fibronectin. This was correlated with a small but significant inhibition of cell adhesion to vitronectin compared with fibronectin, and very significant interference with dissociation of cell: extracellular matrix contacts, resulting either from direct inhibition of the proteolytic activity of urokinase, or from interference with urokinase‐receptor signaling and consequent focal adhesion turnover. Such interference would inhibit cell proliferation by disabling the cells from loosening their matrix contacts in order to proceed through mitosis. This would seriously compromise endothelial recovery in cases of damage to the vascular wall and placement of stents or grafts, where the presence of surface‐adsorbed vitronectin is likely to modulate the tissue response. J. Cell. Biochem. 82: 98–109, 2001. © 2001 Wiley‐Liss, Inc.
Inactivation of multiple targets by nitric oxide in CD95‐triggered apoptosis
Authors: Bernassola Francesca , Catani Maria Valeria , Corazzari Marco , Rossi Antonello , Melino Gerry
Published: August 2002

Nitric oxide (NO) plays an important anti‐apoptotic role by inactivating both upstream and downstream apoptotic molecules. We now report that exogenously supplied NO protected Jurkat T cells from anti‐CD95‐stimulated apoptosis. We have recently shown that nitrosation of the activator protein‐1 (AP‐1) transcriptional factor is crucial for NO‐mediated inhibition of cell death triggered by etoposide or ceramide. Since the inhibition of apoptosis by NO has been reported to involve AP‐1, we evaluated its involvement in in CD95‐mediated cell death. Cross‐linking of CD95 enhanced AP‐1 DNA binding activity and AP‐1‐dependent CD95L transactivation, which were both significantly reduced by different NO‐donors compounds. However, AP‐1 induction does not seem to significantly contribute to anti‐CD95‐triggered apoptosis, as cell death could not be prevented by using the recombinant Fas‐Fc fusion protein which inhibits the CD95/CD95L interaction. We observed that caspase 3‐like activity was negatively modulated by several NO‐donors in vitro and that titratable thiol groups of purified caspases 3, 7, and 9 decreased in the presence of NO‐releasing compounds. In conclusion, we demonstrated that NO‐mediated inhibition of other targets, possibly caspases, but not AP‐1, is a crucial event responsible for protection against anti‐CD95‐stimulated apoptosis. Even though NO affects multiple molecular mechanisms, the relevant target for exerting the cellular effects, may vary among different models. J. Cell. Biochem. 82: 123–133, 2001. © 2001 Wiley‐Liss, Inc.
Parathyroid hormone (1–34) regulates integrin expression in vivo in rat osteoblasts
Authors: Kaiser Edelgard , Sato Masahiko , Onyia Jude E. , Chandrasekhar Srinivasan
Published: August 2002

Intermittent administration of parathyroid hormone (PTH) activates new sites of bone formation by stimulating osteoblast differentiation and function resulting in an increase in bone mass. Because integrins have been shown to play a crucial role in osteoblast differentiation and bone formation, in the present study, we evaluated whether human PTH (1–34) upon administration to rats, influenced integrin expression in osteoblastic cells isolated from the metaphysis and the diaphysis of rat long bones. Initial immunohistochemical evaluation of bone sections demonstrated that the osteoblasts expressed at least αv, α2, α3, and α5β1 integrins. Immunocolocalization studies for integrins and vinculin established that αv, α2, and α5β1, but not α3 integrins were present in the focal adhesion sites of osteoblasts attached to FN coated surfaces. Osteoprogenitor cells isolated from metaphyseal (but not diaphyseal) marrow of rats injected with intermittent PTH (1–34) exhibited greater αv and reduced α2 levels, with no apparent changes in α3, and α5β1 integrin levels, as assessed by immunohistochemistry, Northern, and Western blot analyses. However, these changes were not observed on the same cells treated with PTH in vitro. These observations suggest that integrin modulation by PTH is likely to be indirect and that selective phenotypic expression of integrin subtypes is part of te cascade of events that lead to PTH (1–34) mediated osteoblast differentiation. J. Cell. Biochem. 83: 617–630, 2001. © 2001 Wiley‐Liss, Inc.
Novel computer program for fast exact calculation of accessible and molecular surface areas and average surface curvature
Authors: Tsodikov Oleg V. , Record M. Thomas , Sergeev Yuri V.
Published: August 2002

New computer programs, SurfRace and FastSurf, perform fast calculations of the solvent accessible and molecular (solvent excluded) surface areas of macromolecules. Program SurfRace also calculates the areas of cavities inaccessible from the outside. We introduce the definition of average curvature of molecular surface and calculate average molecular surface curvatures for each atom in a structure. All surface area and curvature calculations are analytic and therefore yield exact values of these quantities. High calculation speed of this software is achieved primarily by avoiding computationally expensive mathematical procedures wherever possible and by efficient handling of surface data structures. The programs are written initially in the language C for PCs running Windows 2000/98/NT, but their code is portable to other platforms with only minor changes in input‐output procedures. The algorithm is robust and does not ignore either multiplicity or degeneracy of atomic overlaps. Fast, memory‐efficient and robust execution make this software attractive for applications both in computationally expensive energy minimization algorithms, such as docking or molecular dynamics simulations, and in stand‐alone surface area and curvature calculations. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 600–609, 2002
Theoretical investigation of electron transfer transition in tetracyanoethylene‐contained organic complexes
Authors: Li Xiang‐Yuan , Hu Chun‐Xiu
Published: August 2002

In this work, the authors use complete active space self‐consistent field method to investigate the photoinduced charge‐separated states and the electron transfer transition in complexes ethylene‐tetracyanoethylene and tetramethylethylene‐tetracyanoethylene. Geometries of isolated tetracyanoethylene, ethylene, and tetramethylethylene have been optimized. The ground state and the low‐lying excited states of ethylene and tetracyanoethylene have been optimized. The state energies in the gas phase have been obtained and compared with the experimentally observed values. The torsion barrier of tetracyanoethylene has been investigated through the state energy calculation at different conformations. Attention has been particularly paid to the charge‐separated states and the electron transfer transition of complexes. The stacked conformations of the donor–acceptor complexes have been chosen for the optimization of the ground and low‐lying excited states. Equilibrium solvation has been considered by means of conductor‐like screening model both in water and in dichloromethane. It has been found that the donor and tetracyanoethylene remain neutral in complexes in ground state 1A1 and in lowest triplet state 3B1, but charge separation appears in excited singlet state 1B1. Through the correction of nonequilibrium solvation energy based on the spherical cavity approximation, π→π* electron transfer transition energies have been obtained. Compared with the experimental measurements in dichloromethane, the theoretical results in the same solvent are found higher by about 0.5 eV. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 874–886, 2002
Evaluation of urinary rapid test for Helicobacter pylori in general practice
Authors: Fujisawa Toru , Kaneko Taimei , Kumagai Toshiko , Akamatsu Taiji , Katsuyama Tsutomu , Kiyosawa Kendo , Tachikawa Tetsuya , Kosaka Osamu , Machikawa Fusaichi
Published: August 2002

There is increasing interest in noninvasive tests for the diagnosis of Helicobacter pylori (H. pylori) infection. One such test, a urine‐based rapid test kit (RAPIRUN H. pylori Antibody, Otsuka Pharmaceutical Co., Ltd.) for detection of antibody to H. pylori, has been developed and is considered ideal. In addition to its noninvasiveness and safe handling—due to use of urine as a sample—the assay procedure used for the urinary rapid test is very simple. Only 10–20 minutes are required to complete an assay, and no instruments are needed. The aim of this study was to examine the clinical usefulness of this urine‐based rapid test. A total of 189 patients, including 76 patients with gastroduodenal disease, were recruited. A pair of random single‐void urine and serum samples was collected from each of the 189 patients, and antibody to H. pylori in the urine and serum samples was measured using the urine‐based rapid test kit and three commercially available serum‐based ELISA kits. For the patients with gastroduodenal disease, invasive diagnostic methods using endoscopic biopsy specimens such as culture, histology, and rapid urease test were also performed. The sensitivity, specificity, and accuracy of the urinary rapid test were evaluated on the basis of the three serum ELISA results or the invasive diagnostic results. In addition, various urinalyses were performed, and the effects of substances existing in urine on the urinary rapid test results were examined. Of the 189 patients, the urinary rapid test was positive for 110 (58.2%), negative for 78 (41.3%), and invalid for only one patient (0.5%). Based on the three serum‐based ELISA results, the sensitivity, specificity, and accuracy of the urinary rapid test were 93.7, 88.9, and 92.2%, respectively. On the basis of the biopsy‐based test results, the sensitivity of the urinary rapid test was 100% and its accuracy (95.2%) was equivalent or superior to that of each serum‐based ELISA. In addition, no significant differences were observed between groups positive and negative on urinary rapid testing in any urinalysis parameter examined. The novel urinary rapid test kit evaluated in this study enables simple, rapid, and accurate diagnosis of H. pylori infection, and is an ideal test method for point‐of‐care testing. J. Clin. Lab. Anal. 15:154–159, 2001. © 2001 Wiley‐Liss, Inc.
Tertullian's motto and Callahan's method
Authors: McNally Richard J.
Published: August 2002

The purposes of this commentary are to provide a critique of Callahan's (this issue) article on Thought Field Therapy (TFT) and to discuss when our commitment to intellectual open‐mindedness requires that we attend to nontraditional treatment interventions in clinical psychology. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1171–1174, 2001.
Heart rate variability does not tap putative efficacy of Thought Field Therapy
Authors: Kline John P.
Published: August 2002

Callahan (2001) has offered a series of case reports in an effort to validate the rationale and methods of Thought Field Therapy (TFT). These case reports employ subjective ratings, that is, the Subjective Units of Distress (SUD) rating scale as well as a gross measure of heart rate variability (HRV). My criticisms center around (a) inappropriately strong inferences given exclusive reliance on case reports, a potentially biased sample, and lack of appropriate controls; (b) misinterpretation of statistical artifact as systematic effect; (c) lack of systematic evaluation of HRV changes; and (d) erroneous interpretation of HRV. Callahan's article provides no evidence for the efficacy of TFT nor does it provide evidence for the credibility of TFT's rationale. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1187–1192, 2001.
Cadherins in neural crest cell development and transformation
Authors: Pla Patrick , Moore Robert , Morali Olivier G. , Grille Sylvia , Martinozzi Silvia , Delmas Véronique , Larue Lionel
Published: August 2002

Cadherins constitute a superfamily of cell adhesion molecules involved in cell‐cell interaction, histogenesis and cellular transformation. They have been implicated in the development of various lineages, including derivatives of the neural crest. Neural crest cells (NCC) emerge from the dorsal part of the neural tube after an epithelio‐mesenchymal transition (EMT) and migrate through the embryo. After homing and differentiation, NCC give rise to many cell types, such as neurons, Schwann cells and melanocytes. During these steps, the pattern of expression of the various cadherins studied is very dynamic. Cadherins also display plasticity of expression during the transformation of neural crest cell derivatives. Here, we review the pattern of expression and the role of the main cadherins involved in the development and transformation of neural crest cell derivatives. © 2001 Wiley‐Liss, Inc.
Basic fibroblast growth factor modulates the expression of glycophorin A and c‐kit and inhibits erythroid differentiation in K562 cells
Authors: Burger Patricia E. , Lukey Pauline T. , Coetzee Sandra , Wilson E. Lynette
Published: August 2002

Basic fibroblast growth factor (bFGF) is produced by bone marrow stromal cells as well as by normal and leukemic hematopoietic cells. In this study, we examine the direct effects of bFGF on erythroid differentiation in K562 cells in order to determine whether bFGF can promote the expression of a primitive phenotype. Low levels of bFGF inhibited erythroid differentiation as evidenced by decreased expression of glycophorin A and increased expression of c‐kit. bFGF also increased both the numbers and the sizes of colonies of K562 cells in soft agar assays. The addition of TGF‐β to these cells induced erythroid differentiation which resulted in an increase in glycophorin A and a decrease in c‐kit. The simultaneous addition of bFGF and TGF‐β to K562 cells prevented both the TGF‐β‐mediated increase in glycophorin A expression and the decrease in c‐kit expression associated with erythroid differentiation. bFGF antagonised the TGF‐β‐mediated promotion of erythroid differentiation in K562 cells in a dose dependent manner and these two cytokines counteracted each other on an approximately molar basis. These results indicate that bFGF alone increases expression of c‐kit and promotes a primitive phenotype in K562 cells. In addition, bFGF counteracts the effects of differentiation‐inducing cytokines, such as TGF‐β, on hematopoietic cells. It is therefore possible that enhanced production of bFGF by leukemic cells could contribute to their neoplastic phenotype by opposing the effects of negative regulators or cytokines that induce differentiation. J. Cell. Physiol. 190: 83–91, 2002. © 2002 Wiley‐Liss, Inc.
Expression of matrix metalloproteinase‐2 and ‐9 and their inhibitors, tissue inhibitor of metalloproteinase‐1 and ‐2, in primary cultures of human prostatic stromal and epithelial cells*†
Authors: Wilson Michael J. , Sellers Robert G. , Wiehr Carol , Melamud Ori , Pei Duanqing , Peehl Donna M.
Published: August 2002

The production of matrix metalloproteinases (MMPs) by prostatic epithelial and/or neighboring stromal cells is considered to be a property that gives cells the capability to penetrate extracellular matrix barriers in normal or neoplastic growth. In order to examine the role of MMPs in the prostate, we evaluated the expression of MMP‐2 and ‐9 and the tissue inhibitors of matrix metalloproteinases (TIMP)‐1 and ‐2 in primary cultures of prostatic stromal and epithelial cells. These cells were isolated from normal tissues of the different zones of the prostate, from benign prostatic hyperplasia (BPH) and from cancer. Stromal cells, regardless of tissue of origin, secreted the 72‐kDa proenzyme form of MMP‐2, whereas conditioned media (CM) from epithelial cells demonstrated little/no pro‐MMP‐2 as examined by zymography. Either type of cell did not secrete MMP‐9. RT‐PCR evaluation showed stromal cells expressed transcripts for MMP‐2, but not for MMP‐9. Transcripts for MMP‐9 were detected in epithelial cells, although no MMP‐9 activity was detected in their CM. Treatment of stromal cells with 1 or 10 ng/ml of transforming growth factor‐beta (TGF‐β) moderately increased secretion of pro‐MMP‐2 protein with little change in MMP‐2 RNA. However, treatment of epithelial cells with TGF‐β induced expression and secretion of both MMP‐2 and ‐9. The effect of TGF‐β on expression of MMPs by epithelial cells was not duplicated or affected by treatment with insulin‐like growth factor (IGF)‐1, epidermal growth factor (EGF), platelet‐derived growth factor (PDGF), or basic fibroblast growth factor (bFGF). Stromal cells expressed transcripts of both TIMP‐1 and ‐2. Epithelial cells expressed TIMP‐1, but little TIMP‐2. TGF‐β did not regulate the expression of TIMP‐1 or ‐2 in either stromal or epithelial cells. Our results suggest that the elevated levels of MMP‐2 and ‐9 observed in prostate development and cancer may be due to the elevated TGF‐β associated with these tissues. J. Cell. Physiol. 191: 208–216, 2002. Published 2002 Wiley‐Liss, Inc.
Differential effects of osteogenic protein‐1 (BMP‐7) on gene expression of BMP and GDF family members during differentiation of the mouse MC615 chondrocyte cells
Authors: Yeh Lee‐Chuan C. , Mallein‐Gerin Frederic , Lee John C.
Published: August 2002

The mRNA expression patterns of several bone morphogenetic proteins (BMPs) and growth differentiation factors (GDFs) in long‐term cultures of the clonal mouse chondrocyte cell line MC615 were examined. Distinct spatial and temporal patterns of expression of BMPs and GDFs were observed. The temporal orders of expression were correlated with those of several biochemical markers characteristic of chondrocytic cell differentiation. BMP‐1, ‐2, ‐5, and ‐6 mRNA expression increased throughout the chondrogenic process and BMP‐4 mRNA expression was not changed. GDF‐1 and ‐3 mRNA expression increased throughout the chondrogenic process, and GDF‐5, ‐6, ‐8, and ‐9 mRNA expressions were not changed. Effects of osteogenic protein‐1 (OP‐1, BMP‐7) on the expression patterns of several other members of the BMP family and of the GDF family were also examined. OP‐1 downregulated the BMP‐1, ‐4, ‐5, and ‐6 mRNA expression by a maximal 3‐, 5‐, 2.5‐, and 3‐fold, respectively. The BMP‐2 mRNA expression was not changed significantly by a low concentration of OP‐1, but was increased at 200 ng/ml at day 7 of treatment. In contrast to the BMPs, OP‐1 upregulated significantly the six GDF members examined (GDF‐1, ‐3, ‐5, ‐6, ‐8, and ‐9) by three‐ to four‐fold. Our findings demonstrate that OP‐1 differentially regulates the mRNA expression of several related members of the BMP family and upregulates the mRNA expression of several members of the GDF family. The observations suggest that OP‐1 action on cartilage differentiation involves a complex regulation of gene expression of several members of the BMP and the GDF family. © 2002 Wiley‐Liss, Inc.
PPARγ ligands suppress proliferation of human urothelial basal cells in vitro
Authors: Kawakami Satoru , Arai Gaku , Hayashi Tetsuo , Fujii Yasuhisa , Xia Guangbin , Kageyama Yukio , Kihara Kazunori
Published: August 2002

Expression of peroxisome proliferator‐activated receptor (PPAR) γ in the human urinary tract through embryonic development suggests its possible roles in the development, proliferation, and differentiation of uroepithelium. Little is known, however, about physiological roles of PPARγ in the urinary tract. We investigated effects of PPARγ ligands on the proliferation of normal human urothelial cells and stromal cells cultivated from surgical specimens. Active proliferation in vitro as well as high molecular weight cytokeratin expression indicated that cultured urothelial cells possess basal cell phenotype. PPARγ protein, expressed predominantly in the epithelial layer of the normal human urinary tract in vivo, was abundantly expressed in urothelial cells but barely detectable in stromal cells in vitro. Natural ligand for PPARγ, 15‐deoxy‐Δ12,14 prostaglandin J2 (15d‐PGJ2), as well as synthetic ones, troglitazone and pioglitazone, suppressed proliferation of the urothelial cells dose‐dependently. These effects were PPARγ specific because clofibrate or PGF2α did not affect proliferation of urothelial cells. Neither 9‐cis retinoic acid or all‐trans retinoic acid (ATRA) at 1 μM showed any synergism on the antiproliferative effects of PPARγ ligands. Urothelial cells treated with PPARγ ligands showed drastic morphologic changes and cell cycle arrest at G0/G1 phase accompanied with increased mRNA level of a cyclin‐dependent kinase inhibitor p21(WAF1/CIP1). Since 15d‐PGJ2 is present in vivo during the resolution phase of inflammation, these results indicated that PPARγ might be involved in the terminal phase of urothelial re‐epithelialization processes. © 2002 Wiley‐Liss, Inc.
Role of MED1 (MBD4) Gene in DNA repair and human cancer
Authors: Bellacosa Alfonso
Published: August 2002

The human protein MED1, also known as MBD4, was isolated in a yeast two‐hybrid screening as an interactor of the mismatch repair protein MLH1. MED1 contains an N‐terminal 5‐methylcytosine binding domain (MBD), which allows binding to methylated DNA, and a C‐terminal catalytic domain with homology to bacterial DNA damage‐specific glycosylases/lyases. This suggests that DNA methylation may play a role in human DNA repair. MED1 acts as a mismatch‐specific DNA N‐glycosylase active on thymine, uracil, 5‐fluorouracil and, weakly, 3,N4‐ethenocytosine paired with guanine. The glycosylase activity of MED1 prefers substrates in which the G:T mismatch is present in the context of methylated or unmethylated CpG sites. Since G:T mismatches can originate via spontaneous deamination of 5‐methylcytosine to thymine, MED1 appears to act as a caretaker of genomic fidelity at CpG sites. Mutagenesis caused by these deamination events is a frequent mechanism of genetic instability in cancer; thus, based on the biochemical activity of its gene product, MED1 is a candidate tumor suppressor gene. Indeed, frameshift mutations of the MED1 gene have been reported in human colorectal, gastric, endometrial, and pancreatic cancer. In the future, efforts should be directed toward investigations of the functional role of the MED1 gene in the pathogenesis, prevention, and treatment of human cancer. © 2001 Wiley‐Liss, Inc.