bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects and characterization of paracrine factors produced by human prostate stromal cells in bioassays using rat Sertoli cells, LNCaP tumor cells, and cultured prostate epithelial cells
Authors: Goossens Karine , Deboel Ludo , Swinnen Johannnes V. , De Gendt Karel , Rombauts Wilfried , Verhoeven Guido 
Published: August 2002

AbstractBACKGROUNDProstatic stroma affects both proliferation and differentiation of epithelial cells but the factors involved remain poorly understood. In order to identify and characterize potential paracrine mediators, we studied the effects of human prostate fibroblast‐conditioned media (PFCM) in three bioassay systems.METHODSThe first bioassay uses transferrin secretion by cultured rat Sertoli cells as an endpoint for differentiating activity. Factors active in this (heterologous) assay were compared to PModS, a mediator of mesenchymal–epithelial interactions in the testis, also produced by rat prostate stromal cells. The two other (homologous) bioassays use LNCaP tumor cells or subcultured human prostate epithelial cells (PEC) as targets. Differentiation is evaluated by prostate‐specific antigen (PSA) secretion and reverse transcriptase‐polymerase chain reaction (RT‐PCR) for a number of markers of epithelial function. Proliferation is assayed by measurements of DNA and thymidine incorporation.RESULTSPFCM markedly stimulates transferrin production by Sertoli cells. The main factor(s) involved are acid stable and bind to heparin. However, both their size (approximately 37 kDa) and their behavior on reversed‐phase chromatography differ from that of PModS. Although PFCM increases total RNA content of LNCaP, it does not increase or restore differentiated function of LNCaP or PEC. Proliferative effects are observed in LNCaP and these effects cannot be neutralized by an antiserum directed against basic fibroblast growth factor (bFGF). Antiproliferative effects are observed in PEC and these effects are largely due to transforming growth factor‐β (TGF‐β).CONCLUSIONSPFCM provokes differentiating effects in a Sertoli cell bioassay, but unlike with rat stromal cells, the factor(s) involved differ from PModS. In the two homologous systems studied, differentiating effects could not be demonstrated and discordant effects were noted on proliferation. Various bioassay systems will be required to identify the spectrum of mediators present in PFCM. Prostate 48:104–117, 2001. © 2001 Wiley‐Liss, Inc.
Silk fibroin: Structural implications of a remarkable amino acid sequence
Authors: Zhou Cong‐Zhao , Confalonieri Fabrice , Jacquet Michel , Perasso Roland , Li Zhen‐Gang , Janin Joel 
Published: August 2002

AbstractThe amino acid sequence of the heavy chain of Bombyx mori silk fibroin was derived from the gene sequence. The 5,263‐residue (391‐kDa) polypeptide chain comprises 12 low‐complexity “crystalline” domains made up of Gly–X repeats and covering 94% of the sequence; X is Ala in 65%, Ser in 23%, and Tyr in 9% of the repeats. The remainder includes a nonrepetitive 151‐residue header sequence, 11 nearly identical copies of a 43‐residue spacer sequence, and a 58‐residue C‐terminal sequence. The header sequence is homologous to the N‐terminal sequence of other fibroins with a completely different crystalline region. In Bombyx mori, each crystalline domain is made up of subdomains of ∼70 residues, which in most cases begin with repeats of the GAGAGS hexapeptide and terminate with the GAAS tetrapeptide. Within the subdomains, the Gly–X alternance is strict, which strongly supports the classic Pauling–Corey model, in which β‐sheets pack on each other in alternating layers of Gly/Gly and X/X contacts. When fitting the actual sequence to that model, we propose that each subdomain forms a β‐strand and each crystalline domain a two‐layered β‐sandwich, and we suggest that the β‐sheets may be parallel, rather than antiparallel, as has been assumed up to now. Proteins 2001;44:119–122. © 2001 Wiley‐Liss, Inc.
Adenine recognition: A motif present in ATP‐, CoA‐, NAD‐, NADP‐, and FAD‐dependent proteins
Authors: Denessiouk Konstantin A. , Rantanen Ville‐Veikko , Johnson Mark S. 
Published: August 2002

AbstractAdenosine triphosphate (ATP) plays an essential role in energy transfer within the cell. In the form of NAD, adenine participates in multiple redox reactions. Phosphorylation and ATP‐hydrolysis reactions have key roles in signal transduction and regulation of many proteins, especially enzymes. In each cell, proteins with many different functions use adenine and its derivatives as ligands; adenine, of course, is present in DNA and RNA. We show that an adenine binding motif, which differs according to the backbone chain direction of a loop that binds adenine (and in one variant by the participation of an aspartate side‐chain), is common to many proteins; it was found from an analysis of all adenylate‐containing protein structures from the Protein Data Bank. Indeed, 224 protein–ligand complexes (86 different proteins) from a total of 645 protein structure files bind ATP, CoA, NAD, NADP, FAD, or other adenine‐containing ligands, and use the same structural elements to recognize adenine, regardless of whether the ligand is a coenzyme, cofactor, substrate, or an allosteric effector. The common adenine‐binding motif shown in this study is simple to construct. It uses only (1) backbone polar interactions that are not dependent on the protein sequence or particular properties of amino acid side‐chains, and (2) nonspecific hydrophobic interactions. This is probably why so many different proteins with different functions use this motif to bind an adenylate‐containing ligand. The adenylate‐binding motif reported is present in “ancient proteins” common to all living organisms, suggesting that adenine‐containing ligands and the common motif for binding them were exploited very early in evolution. The geometry of adenine binding by this motif mimics almost exactly the geometry of adenine base‐pairing seen in DNA and RNA. Proteins 2001;44:282–291. © 2001 Wiley‐Liss, Inc.
A monoclonal antibody‐based ELISA for the analysis of the insecticide flucythrinate in environmental and crop samples
Authors: Nakata Masanobu , Fukushima Azusa , Ohkawa Hideo 
Published: August 2002

AbstractA competitive enzyme‐linked immunosorbent assay (ELISA) has been developed for the detection of the insecticide flucythrinate in environmental and food samples. Two types of haptens, the acid moiety that is the hydrolyzed product of flucythrinate, and the carboxylated propyl derivative of the alcohol moiety, were used to prepare monoclonal antibodies (MAbs). Five MAbs, which raised against the former hapten, were reactive with flucythrinate. Among them, MAb F1A27‐4 showed the highest activity toward flucythrinate, and did not cross‐react with other pyrethroids such as cycloprothrin, fenvalerate, fluvalinate, etofenprox and silafluofen. The assay conditions of indirect competitive ELISA with MAb F1A27‐4 were studied to optimize the detection of flucythrinate in environmental and food samples. Incubation at 4 °C in the assay buffer, pH 8, with 300 mM sodium chloride improved the sensitivity. The addition of rabbit serum albumin or rabbit antiserum and the presence of 50 ml litre−1 of methanol reduced matrix effects of the samples. Under optimized conditions, the ELISA detected flucythrinate spiked in water, soil, and extracts of apple and tea samples down to 10 mg litre−1, 0.2 mg litre−1, 0.3 mg litre−1 and 0.3 mg litre−1, respectively. The mean recovery and CV ranged from 91% to 120% and from 5% to 12%, respectively. The ELISA results in apple samples correlated well with those from LC–MS analysis (r2 = 0.99, n  = 12).© 2001 Society of Chemical Industry
Resistance of a soybean cell line to oxyfluorfen by overproduction of mitochondrial protoporphyrinogen oxidase
Authors: Warabi Eiji , Usui Kenji , Tanaka Yoshiyuki , Matsumoto Hiroshi 
Published: August 2002

AbstractThe diphenyl ether herbicide oxyfluorfen (2‐chloro‐4‐trifluoromethylphenyl 3‐ethoxy‐4‐nitrophenyl ether) inhibits protoporphyrinogen oxidase (Protox) which catalyzes the oxidation of protoporphyrinogen IX (Protogen) to protoporphyrin IX (Proto IX), the last step of the common pathway to chlorophyll and haeme biosynthesis. We have selected an oxyfluorfen‐resistant soybean cell line by stepwise selection methods, and the resistance mechanism has been investigated. No growth inhibition was observed in resistant cells at a concentration of 10−7 M oxyfluorfen, a concentration at which normal cells did not survive. While the degree of inhibition of total extractable Protox by oxyfluorfen was the same in both cell types, the enzyme activity in the mitochondrial fraction from non‐treated resistant cells was about nine‐fold higher than that from normal cells. Northern analysis of mitochondrial Protox revealed that the concentration of mitochondrial Protox mRNA was much higher in resistant cells than that in normal cells. There were no differences in the absorption and metabolic breakdown of oxyfluorfen. The growth of resistant cells was also insensitive to oxadiazon [5‐tert‐butyl‐3‐(2,4‐dichloro‐5‐isopropoxyphenyl)‐1,3,4‐oxadiazol‐2‐(3H)‐one], the other chemical class of Protox inhibitor. Therefore, the resistance of the selected soybean cell line to oxyfluorfen is probably mainly due to the overproduction of mitochondrial Protox.© 2001 Society of Chemical Industry
Fate of spinosad in litter and soils of a white spruce plantation in central Ontario
Authors: Thompson Dean G , Harris Brenda J , Buscarini Teresa M , Chartrand Derek T 
Published: August 2002

AbstractSpinosad is a natural insecticide with potential as a novel biorational control agent for spruce budworm (Choristoneura fumiferana [Clem]), the most destructive insect defoliator of spruce and balsam fir in Canada. Concurrent terrestrial fate experiments were conducted under full coniferous canopy and in a natural opening of a mature white spruce (Picea glauca [Moench]) plantation of central Ontario to examine the fate and persistence of spinosad in the forest floor and underlying soils. Mean initial residues of spinosyn A and D were approximately 0.2 and 0.02 µg g−1, respectively, in thatch and exposed soils, but were substantially higher, 2.72 and 0.36 µg g−1, in litter under coniferous canopy. Results demonstrated that spinosad residues in spruce litter, graminaceous thatch and exposed sandy loam soils dissipated rapidly, following hyperbolic or exponential decline models. Dissipation time (DT50) values ranged from 2.0 to 7.8 days, depending on matrix and experimental conditions. Transient increases in demethylated metabolite residues confirmed that the parent product was degraded in situ. No evidence of vertical mobility of any of the analytes was observed.© 2002 Society of Chemical Industry
Synthesis of biotin conjugates of the antifungal compound cymoxanil
Authors: Evans Karen Anderson , Kane Charles T , Tice Colin M 
Published: August 2002

AbstractBiotin conjugates are of considerable value in investigating the mode of action of biologically active compounds. Two biotin conjugates related to the antifungal compound cymoxanil [1‐(2‐cyano‐2‐methoximinoacetyl)‐3‐ethyl urea] were prepared as the first step in an effort to employ display cloning to identify the compound's target site. In the first conjugate, prepared in five steps, the biotin moiety was attached at the position occupied by the ethyl group in cymoxanil. In the second conjugate, prepared in four steps, the biotin moiety was attached through the oxime functional group.© 2002 Society of Chemical Industry
Fullerene‐based amino acids and peptides
Authors: Bianco Alberto , Da Ros Tatiana , Prato Maurizio , Toniolo Claudio 
Published: August 2002

AbstractRecent advances in the chemistry of fullerene have allowed the synthesis of many classes of novel fullerene derivatives. Among these classes, fullerene‐based amino acids and peptides are particularly interesting, both for structural studies and biological applications. In this review, we will discuss our own achievements in this rapidly growing field. In particular, the application of fulleroproline (Fpr) amino acids and peptides to medicinal chemistry and material science will be highlighted. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Conformational flexibility of three cytoplasmic segments of the angiotensin II AT1A receptor: a circular dichroism and fluorescence spectroscopy study
Authors: Pertinhez Thelma A. , Krybus Regina , Cilli Eduardo M. , Paiva Antonio C. M. , Nakaie Clóvis R. , Franzoni Lorella , Sartor Giorgio , Spisni Alberto , Schreier Shirley 
Published: August 2002

AbstractThe conformation of three synthetic peptides encompassing the proximal and distal half of the third intracellular loop (Ni3 and Ci3) and a portion of the cytoplasmic tail (fCT) of the angiotensin II AT1A receptor has been studied using circular dischroism and fluorescence spectroscopies. The results show that the conformation of the peptides is modulated in various ways by the environmental conditions (pH, ionic strength and dielectric constant). Indeed, Ni3 and fCT fold into helical structures that possess distinct stability and polarity due to the diverse forces involved: mainly polar interactions in the first case and a combination of polar and hydrophobic interactions in the second. The presence of these various features also produce distinct intermolecular interactions. Ci3, instead, exists as an ensemble of partially folded states in equilibrium. Since the corresponding regions of the angiotensin II AT1A receptor are known to play an important role in the receptor function, due to their ability to undergo conformational changes, these data provide some new clues about their different conformational plasticity. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd.
The Eurocode for Structural loading: Eurocode 1
Authors: Gulvanessian H , Menzies J B 
Published: August 2002

AbstractEurocode 1: Actions on Structures is one of the international unified set of codes of practice known as the Structural Eurocodes, now in an advanced state of development in Europe. It provides comprehensive information and guidance on all actions (loads) that it is normally necessary to consider in the design of building and civil engineering structures. The preparation of Eurocode 1, in ten Parts, was initiated by the European Union in 1985. All Parts have been published by the European Committee for Standardization (CEN) as European pre‐standards (ENV) for voluntary use and a five‐year programme to convert them to European Standards (EN) is now at an advanced stage. This article describes the scope of Eurocode 1 and its main provisions.
Research and development in precast concrete framed structures
Authors: Elliott Kim S 
Published: August 2002

AbstractResearch work on precast concrete framed structures carried out over the past 20 years has culminated with the large‐scale testing of a five‐storey frame in the USA, a pan‐European project on the structural behaviour of frame connections, and the optimization of some highly engineered concrete elements. This paper reviews the most important advances, explaining to designers the relevance of the results of tests carried out on complete sway frames, on floor systems and connections subjected to gravity, horizontal and catenary forces, and on the wide‐ranging developments of elements such as prestressed hollow core floor units. The design engineer now has more information, through full‐scale experimental testing, realistic numerical studies and 3‐dimensional nonlinear computer programs, to enable safer and more efficient design than ever before.
Inhibition of the superoxide anion release and hydrogen peroxide formation in PMNLs by flavonolignans
Authors: Varga Zsuzsa , Czompa Andrea , Kakuk György , Antus Sándor 
Published: August 2002

AbstractThe mixture of flavonolignans [LegalonR: silybin (2a), isosilybin (3), silydianin (4) and silychristin (5)] and derivatives of silybin (2b–d) were assessed for their inhibitory activity on the oxidative burst of PMA‐stimulated human PMNLs. The inhibitory effect of flavonolignans on O2− release were compared with that of vitamin E (1). The flavonolignans tested exhibited the following order in inhibition of O2− release by PMA‐stimulated PMNLs: 5,7,4′′‐ trimethylsilybin (2c) ≈ vitamin E (1) > LegalonR ≥ peracetylsilybin (2b) > silybin (2a) > peracetyl‐5,7,4′′‐trimethylsilybin (2d). The flavonolignans inhibited not only the O2− release, but also the H2O2 formation in PMA‐stimulated PMNLs. The inhibitory capacity of flavonolignans on H2O2 formation was similar to their inhibitory capacity on O2− release. These data suggest that the flavonolignans have antioxidant properties on the PMNL oxidative burst. The fact that the trimethyl derivative of silybin (2c) has a greater inhibitory effect than silybin itself suggests that the efficacy of the antioxidant properties is dependent on the lipophilicity of the molecules. This is underlined by the fact that peracetylation of all of the hydroxyl groups in silybin resulted in a total loss of the antioxidant activity of the molecule. In summary, flavonolignans inhibit the oxidative burst of PMNLs, and this inhibitory effect depends on the chemical structure of the flavonolignans. Copyright © 2001 John Wiley & Sons, Ltd.
Manage your clinical study like an auditor
Authors: Wilkins Byard Marlene 
Published: August 2002

AbstractClinical research associates (CRAs) often panic when faced with the prospect of a site audit or inspection, and they want advice as to how to prepare for an auditor visit or inspector visit. The key to a perpetual state of readiness is to manage your clinical study as if you were an auditor. Copyright © 2002 John Wiley & Sons, Ltd.
Does quality assurance apply to development planning?
Authors: Bentzinger Claude , Schulz Miklos L , O'Brien‐Hitching Patrick 
Published: August 2002

AbstractNew product development planning is a complex process and the quality of the planning will have a profound effect on time to market(s) and the commercial success of a therapeutic innovation. Quality assurance has an important role in the planning process. We have drawn up a list of quality assurance criteria applicable to the planning process in R&D, clinical investigation and new business development. The list is by no means exhaustive and we welcome thoughts and comments on other criteria and other areas. Perhaps the present review will stimulate interest and raise readers' awareness of the formidable array of different considerations that must be taken into account if we are to create better therapies for tomorrow's patients. Copyright © 2002 John Wiley & Sons, Ltd.
Standard operating procedures for clinical research personnel – Part 11
Authors: Bohaychuk Wendy , Ball Graham 
Published: August 2002

AbstractThis is the eleventh in a series of articles containing proposals for wording and content of standard operating procedures (SOPs) for clinical research activities conducted by sponsors and Contract Research Organisations (CROs). The procedures include those required by the International Conference on Harmonisation (ICH), the Food and Drug Administration (FDA), many other guidelines and regulations, and ‘best practice’ observed by the authors. The model forms require modification for actual use. In this article, SOPs are presented for selection of CROs (SOP 326) and selection of clinical laboratories (SOP 327). (The full text of all 101 SOPs is available from the authors.) Copyright © 2002 John Wiley & Sons, Ltd.
Control charts for positively‐skewed populations with weighted standard deviations
Authors: Chang Young Soon , Bai Do Sun 
Published: August 2002

AbstractThis paper proposes a heuristic method of constructing $\bar{X}$, cumulative sum and exponentially weighted moving average control charts for skewed populations with weighted standard deviations obtained by decomposing the standard deviation into upper and lower deviations adjusted in accordance with the direction and degree of skewness. These control charts, however, reduce to standard control charts when the underlying distribution is symmetric. Simple formulae are derived to estimate unknown process parameters from means and ranges of subgroups. The false alarm rates of these control charts are compared with those of existing control charts when the underlying distribution is Weibull, gamma, or lognormal. Simulation results show that considerable improvement over the existing methods can be achieved when the underlying distribution is skewed. Copyright © 2001 John Wiley & Sons, Ltd.
An economic model for \font\twelveit=cmti10 scaled 1600$\overline{\kern‐0.85ex\hbox{\twelveit X}}$\nopagenumbers\end and R charts with time‐varying parameters
Authors: Ohta Hiroshi , Kimura Aritoshi , Rahim Abdur 
Published: August 2002

AbstractThis paper proposes an economic model for the selection of time‐varying control chart parameters for monitoring on‐line the mean and variance of a normally distributed quality characteristic. The process is subject to two independent assignable causes. One cause changes the process mean and the other changes the process variance. The occurrence times of these assignable causes are described by Weibull distributions having increasing failure rates. The paper combines two existing models: (I) the model of Ohta and Rahim (IIE Transactions 1997; 29:481–486) for a dynamic economic design of $\overline{X}$\nopagenumbers\end control charts, where a single assignable cause occurs according to a Weibull distribution and all design parameters are time varying; (II) the model of Costa and Rahim (QRE International 2000; 16:143–156) for the joint economic design of $\overline{X}$\nopagenumbers\end and R control charts where two assignable causes occur independently according to Weibull distribution, with variable sampling intervals. The advantages of the proposed model over traditional $\overline{X}$\nopagenumbers\end and R control charts with fixed parameters are presented. Copyright © 2002 John Wiley & Sons, Ltd.
Structural stability analysis of Wigner crystal with Gaussian and Yukawa‐type positive background
Authors: Palanichamy R. Rajeswara , Iyakutti K. 
Published: August 2002

AbstractCalculations of the ground‐state energies of Wigner crystals having simple cubic (sc), body‐centered cubic (bcc), face‐centered cubic (fcc), diamond, and perovskite structures and (hence) the analysis of relative stability of Wigner crystals of various different structures are reported. The positive background is represented by a periodic array of Gaussians and Yukawa‐type distribution. The effects on stability of the perturbation due to the underlying lattice have been demonstrated. Among the structures, the bcc lattice still remains the most stable known arrangement and the Yukawa‐type background leads to a lower ground state energy value compared to a Gaussian type. The calculations are done for the range of the density parameter rs corresponding to low densities for the above two cases. The range of low‐density region favorable for Wigner crystallization is found to be above rs=20. The role of correlation energy is suitably taken into account. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Ladder operators for the Morse potential
Authors: Dong Shi‐Hai , Lemus R. , Frank A. 
Published: August 2002

AbstractA realization of the raising and lowering operators for the Morse potential is presented. It is shown that these operators satisfy the commutation relations for the SU(2) group. Closed analytical expressions are obtained for the matrix elements of different operators such as 1/y and d/dy. The harmonic limit of the SU(2) operators is also studied and an approach previously proposed to calculate the Franck–Condon factors is discussed. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001