bluuebunny/crossref_metadata_2025 huggingface dataset:
First trimester maternal serum placenta growth factor (PIGF)concentrations in pregnancies with fetal trisomy 21 or trisomy 18
Authors: Spencer Kevin , Liao Adolfo W. , Ong Charas Y. T. , Geerts Lut , Nicolaides Kypros H.
Published: August 2002

Placenta growth factor (PIGF), an angiogenic factor belonging to the vascular endothelial growth factor family, pregnancy‐associated plasma protein A (PAPP‐A) and free β‐human chorionic gonadotrophin (β‐hCG) were measured in maternal serum from 45 pregnancies with trisomy 21, 45 with trisomy 18 and 493 normal controls at 10–13 completed weeks of gestation. In the normal pregnancies maternal serum PIGF levels increased exponentially with gestation. The median multiple of the median (MoM) PIGF concentration in the trisomy 21 group (1.26 MoM) was significantly higher (p<0.0001) than in the control group (1.00 MoM). In the trisomy 18 group the median PIGF was lower (0.889 MoM) but this did not quite reach significance (p=0.064). The corresponding median MoM values for PAPP‐A were 1.00 MoM for the controls, 0.49 MoM for trisomy 21 and 0.16 MoM for trisomy 18. The median MoM values for free β‐hCG were 1.00 MoM for the controls, 2.05 MoM for trisomy 21 and 0.38 MoM for trisomy 18. In the control group there was a small but significant correlation of PIGF with free β‐hCG (r=+0.1024) and PAPP‐A (r=+0.2288). In the trisomy 18 group there was a significant association between PIGF and free β‐hCG (r=+0.2629) but not with PAPP‐A (r=+0.0038). In the trisomy 21 group there was a small but significant association with PAPP‐A (r=+0.1028) but not with free β‐hCG (r=+0.0339). The separation of affected and unaffected pregnancies in maternal serum PIGF is small, and therefore it is unlikely that measurement of PIGF would improve screening for these abnormalities provided by the combination of fetal nuchal translucency and maternal serum PAPP‐A and free β‐hCG. Copyright © 2001 John Wiley & Sons, Ltd.
Enlarged fetal bladders: aetiology, management and outcome
Authors: McHugo Jo , Whittle Martin
Published: August 2002

Ultrasound routinely identifies the fetal bladder from 10 weeks of gestation. Understanding the normal embryology of the fetal bladder forms the basis of understanding the mechanisms for pathology. Early onset megacystis <12 mm (maximum diameter) frequently regresses spontaneously however when associated with other structural abnormalities 40% are chromosomally abnormal. Survival in this group is rare and the underlying histopathology is of urethral fibrostenosis. Second and third trimester megacystic indicates a heterogenous group where a precise antenatal diagnosis may be impossible. A distended thick wall bladder associated with a dilated posterior urethra and oligohydramnios is pathonemonic of posterior urethral valves; without this combination of ultrasound signs the underlying pathology is less certain. Prediction of other aetiologies for the megacystis is less accurate but includes primary reflux, cloacal plate, urethral duplication and megacystic microcolon in the differential diagnosis. Robust published data is currently unavailable to define appropriate management for individual cases of megacystis. Therefore current best practice for antenatal management will be discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Methylphenidate in children with hyperactivity: review and cost–utility analysis
Authors: Gilmore Anna , Milne Ruairidh
Published: August 2002

Objective

To evaluate the effectiveness and cost effectiveness of methylphenidate in the treatment of children with hyperkinetic disorder as defined using ICD‐10 criteria.

Design

Comprehensive literature review and cost utility analysis comparing methylphenidate treatment with placebo. Costs and effects were estimated from a NHS perspective according to the methodology developed by the previous South and West Development and Evaluation Committee. The number of Quality Adjusted Life Years (QALYs) gained was estimated by using the Index of Health Related Quality of Life to model treatment effects.

Results

Evidence from good and medium quality randomized controlled trials shows benefits of methylphenidate over weeks and months respectively. Evidence beyond 6 months is poorer and it is uncertain whether effects of methylphenidate persist into adolescence and adulthood. Methylphenidate is of reasonable cost‐effectiveness when considering short‐ and medium‐ term benefits with an estimated cost per QALY of £7400 to £9200 at 1997 prices.

Conclusions

Short‐term treatment of hyperkinetic children with methylphenidate is effective and cost effective. Copyright © 2001 John Wiley & Sons, Ltd.
Drug switching patterns among patients taking non‐steroidal anti‐inflammatory drugs: a retrospective cohort study of a general practitioners database in the United Kingdom
Authors: Langman Michael , Kahler Kristijan H. , Kong Sheldon X. , Zhang Qiaoyi , Finch Elizabeth , Bentkover Judith D. , Stewart Edward J.
Published: August 2002

Objective

To examine the frequency and determinants of switching between different non‐steroidal anti‐inflammatory drugs (NSAIDs) and the relationship with co‐prescription of gastro‐protective drugs (GPDs).

Design

This was an analysis of 30 654 patients receiving a total of 209 140 NSAID prescriptions in the UK from 1 January 1997 to 31 December1998 identified through the MediPlus database. Analyses examined switching, repeat, termination and GPD co‐prescription rates in new and continuing takers according to age and sex.

Results

Each patient received an average of 6.8 prescriptions in the year of study. Of the prescriptions 72.2% were for one of three NSAIDs, ibuprofen, diclofenac, or naproxen, and 7.2% of prescriptions were for fixed combination products of an NSAID plus a gastroprotective drug. At least 16.0% of continuing takers, and 28.5% of new takers switched to another NSAID in the review period. On average, new patients switched more frequently than continuing patients (0.39 switches/patient/year versus 0.23 switches/patient/year, p<0.001). Switching between NSAIDs decreased with age and was less common in women (p<0.05). Switching was associated with a 24% and 33% increased probability of GPD prescription in new and continuing takers, respectively.

Discussion

The frequency of switching, and of GPD co‐prescription at switching, suggest that dissatisfaction with NSAIDs is frequent, and that gastrointestinal intolerance is a common feature of this dissatisfaction. Copyright © 2001 John Wiley & Sons, Ltd.
Contribution of pharmacists to the reporting of adverse drug reactions
Authors: van Grootheest A. C. , van Puijenbroek E. P. , de Jong–van den Berg L. T. W.
Published: August 2002

Purpose

The aim of the study is to get a better view about the possible contribution of pharmacists' reports to the quantity and the quality of reports and in this way to the quality of a voluntary reporting system of adverse drug reactions.

Methods

A total of 15 293 reports, sent to the Netherlands Pharmacovigilance Foundation Lareb between 1995 and 2000 were analysed for the characteristics of pharmacists' reports and the differences with reports from physicians i.e. dispersion of adverse drug reactions in relation to the different System and Organ Classes, the seriousness of the reports according to the CIOMS criteria and the documentation grade of the reports. A total of 200 reports were selected at random and their quality assessed.

Results

Pharmacists are responsible for 40% of the reports sent in to Lareb during this period. Their reports more frequently concern adverse effects in relation to skin and the eyes. Adverse drug reactions reported by pharmacists tend to be less severe than those reported by physicians and pharmacists' reports tend to be of a lower documentation grade than those of physicians. Also, the quality of the clinicial information is higher in physicians' reports.

Conclusions

The contribution of pharmacists to the voluntary reporting system in the Netherlands is of great importance, both for the number and quality of the reports. Copyright © 2002 John Wiley & Sons, Ltd.
The consistency of personality type classification across samples and five‐factor measures
Authors: De Fruyt Filip , Mervielde Ivan , Van Leeuwen Karla
Published: August 2002

Caspi (1998), Asendorpf and Van Aken (1999), and Asendorpf et al. (2001) described three personality types derived from Q‐factor analysis of Q‐sorts or cluster analysis of multiple trait ratings. The types were labelled as resilients, undercontrollers, and overcontrollers and they were described in terms of averaged Five‐Factor Model (FFM) scores. The present study aimed to investigate the consistency and replicability of these prototypes across different FFM measures (i.e. HiPIC and NEO PI‐R) and ages (children and adolescents). In addition, the stability of prototype classification across a 3 year interval was examined. The types described by Caspi and Asendorpf and colleagues were only partially replicable and consistent across ages starting from HiPIC ratings, but not for NEO‐PI‐R ratings. Prototype classification was not stable across a 3 year interval. It is concluded that cluster replicability, consistency, and stability depend on sample characteristics and the multiple trait measures, although these difficulties do not necessarily limit the usefulness of the types for applied purposes. Copyright © 2002 John Wiley & Sons, Ltd.
Dielectric analysis of the linear polymerization of an epoxy resin
Authors: Gallone Giuseppe , Capaccioli Simone , Levita Giovanni , Rolla Pier Angelo , Corezzi Silvia
Published: August 2002

The dielectric properties of a diglycidyl ether of bisphenol A (DGEBA) epoxy resin and n‐butylamine have been studied in the frequency range 100 Hz to 3 GHz at 25 °C. The unreacted mixture showed a single relaxation which gradually split in two relaxations, the separation of which increased as the reaction progressed. The low and high frequency relaxations are attributed to the structural dynamics of the growing macromolecules and to the motions of the dipoles associated with the monomers, respectively. The increase of the structural relaxation time is described by a phenomenological relationship, similar to the Williams–Landel–Ferry equation, that allows estimation of the conversion at vitrification. A marked decrease of the electrical conductivity has also been observed, as a result of the increasing viscosity of the system. The conductivity and the structural relaxation time are correlated by means of a generalized Debye–Stokes–Einstein model. It has also been found that both components of the complex dielectric permittivity, measured at microwave frequencies, yield information on the advancement of the polymerization process.

© 2001 Society of Chemical Industry
Polysaccharides from prickly pear peel and nopals of Opuntia ficus‐indica: extraction, characterization and polyelectrolyte behaviour
Authors: Majdoub Hatem , Roudesli Sadok , Deratani André
Published: August 2002

The extraction at natural pH of carbohydrate polymers from Opuntia ficus‐indica and their physicochemical characterization are reported. Polysaccharides extracted from nopal pulp, nopal peel and pear peel, are denoted NPU, NPE and PPE respectively. For comparison, extraction of the peel of fruit has also been carried out using the conventional acid process generally employed for pectin (PPI). The sugar composition indicates that all the polysaccharides obtained contain anionic moieties, galacturonic acid residues, from 10% for NPU to about 50% for those extracted from peels, the composition of which is typical of pectin. The macromolecular features of these compounds have been characterized by size‐exclusion chromatography coupled with multi‐angle laser light‐scattering detection (SEC–MALLS) and by capillary viscometry, leading to information on conformation and size dimension of macromolecules in dilute aqueous solutions. Our findings show that the polysaccharides from nopals have a random coil structure, whereas those from fruit peel exist as a compact sphere which is assumed to be due to a branched structure. The polyelectrolyte character related to the presence of fixed charges on the chain has been investigated as a function of pH and ionic strength. The conformational change from a compact form in acidic medium to an expanded one takes place in the pH range 4–6. A strong tendency to form aggregates in acidic medium is evidenced by SEC–MALLS. The differences observed in the solution behaviour of the studied polysaccharides are discussed in terms of intra‐ and inter‐macromolecular interactions.

© 2001 Society of Chemical Industry
Stability of the adjustment scales for children and adolescents
Authors: Canivez Gary L. , Perry Amanda R. , Weller Elizabeth M.
Published: August 2002

Investigation of the short‐term (90‐day) stability of the Adjustment Scales for Children and Adolescents is reported for 124 randomly selected children in grades ranging from kindergarten to grade 12. Significant test‐retest stability coefficients were obtained and mean differences across the retest interval did not exceed .8 raw score points. The Solitary Aggressive‐Impulsive, Diffident, and Lethargic/Hypoactive syndromes and the global Underactivity scale showed significant raw score and T score changes across the retest interval, but the effect strengths were small. Syndromic Profile Classifications and Discriminant Classifications were also significantly consistent across the retest interval. Results were similar to those obtained in other stability studies of teacher report behavior rating scales. © 2001 John Wiley & Sons, Inc.
Solvatochromism of carbenium–arene EDA (electrondonor–acceptor) complexes and their behaviour on silica
Authors: Spange Stefan , Fährmann Annett , Reuter Anett , Walther Ralph , Zimmermann Yvonne
Published: August 2002

Spectral characteristics of two different types of electron donor–acceptor (EDA) complexes with charged components (arene–carbenium and anion–π acceptor) are presented. The UV–Vis absorption maxima of the charge‐transfer (CT) band (νmax,CT) of the EDA complexes were measured in various solvents and after adsorption on silica. Tropylium, triarylmethylium and diarylmethylium ions in combination with aromatic π donors, e.g. pyrene, acenaphthene and methoxy‐substituted benzene derivatives and also the tetraethylammonium iodide–1,3,5‐trinitrobenzene complex have been investigated by means of a special UV–Vis technique in transparent slurries of silica nanoparticles in 1,2‐dichloroethane. Multiple linear regression analyses of the νmax,CTvalues of the EDA complexes in various solvents and on silica with the Kamlet–Taft solvent parameters and structure–reactivity terms of the complex components, e.g. the oxidation potential of the arene component or the Hammett substituent constant, σp+, of the arylmethyl component, show their related properties to the solution complexes. The influence of the electron‐pair donating capacity of a solvent on νmax,CTof carbenium/arene complexes was compared with the property of the silica surface in order to link EDA complexes. For the diarylmethyl carbenium ion–pyrene complexes on silica, the presence of a σ‐like structure is discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Syntheses and characterizations of poly[2‐(dimethylamino)ethyl methacrylate]–poly(propylene oxide)–poly[2‐(dimethylamino)ethyl methacrylate] ABA triblock copolymers
Authors: Ni Pei‐Hong , Pan Qi‐Sheng , Zha Liu‐Sheng , Wang Chang‐Chun , Elaïssari Abdelhamid , Fu Shou‐Kuan
Published: August 2002

A novel, near‐monodisperse, well‐defined ABA triblock copolymer, poly[2‐(dimethylamino)ethyl methacrylate]‐b‐poly(propylene oxide)‐b‐poly[2‐(dimethylamino)ethyl methacrylate], was synthesized via oxyanion‐initiated polymerization. The initiator was a telechelic‐type potassium alcoholate prepared from poly(propylene glycol) and KH in dry tetrahydrofuran. The copolymers produced were characterized by Fourier transform infrared, 1H NMR, and gel permeation chromatography (GPC). GPC and 1H NMR analyses showed that the products obtained were the desired copolymers, with narrow molecular weight distributions (ca. 1.09–1.11) very close to that of the original poly(propylene glycol). 1H NMR, surface tension measurements, and dynamic light scattering all indicated that the triblock copolymer led to interesting aqueous solution behaviors, including temperature‐induced micellization and very high surface activity. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 624–631, 2002; DOI 10.1002/pola.10144
Synthesis and characterization of micrometer‐sized particles of narrow size distribution with chloromethyl functionality on the basis of single‐step swelling of uniform polystyrene template microspheres
Authors: Kedem Michal , Margel Shlomo
Published: August 2002

Polystyrene template microspheres of 1.4 ± 0.1 μm were prepared by dispersion polymerization of styrene in a mixture of ethanol and 2‐methoxy ethanol. These template particles were then swelled at room temperature in a single step with emulsion that was prepared in sodium dodecyl sulfate aqueous solution from a swelling solvent (dibutyl phthalate) containing the initiator (benzoyl peroxide) and monomer(s) (chlormethylstyrene, divinylbenzene, or ethylene dimethacrylate). Composite uniform particles composed of the template polystyrene and noncrosslinked or crosslinked polychloromethylstyrene were prepared by polymerizing the monomer(s) within the swelled particles at 73 °C. Crosslinked uniform polychloromethylstyrene particles of higher surface area were formed by dissolving the template polystyrene polymer of the composite particles. The influence of various reaction parameters, such as dibuthyl phthalate concentration, chloromethylstyrene concentration, crosslinker type and concentration, and so forth on the molecular weight, size, size distribution, shape, morphology, surface area, and decomposition temperature of the particles was investigated. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1342–1352, 2002
Poly(2‐hydroxyethyl methacrylate‐co‐N,O‐dimethacryloylhydroxylamine) particles by dispersion polymerization
Authors: Horák Daniel , Chaykivskyy Ostap
Published: August 2002

Poly(2‐hydroxyethyl methacrylate‐co‐N,O‐dimethacryloylhydroxylamine) particles were prepared by dispersion polymerization in toluene/2‐methylpropan‐1‐ol medium using cellulose acetate butyrate and dibenzoyl peroxide (BPO) as a steric stabilizer and initiator, respectively. The particle size was reduced with decreasing solvency of the reaction medium (more nuclei were generated) because the critical chain length of the precipitated oligomers decreased with an increasing toluene content, which is a poorer solvent for the polymer than 2‐methylpropan‐1‐ol. There is an optimum initiator concentration (2 wt % BPO relative to monomers) for producing low‐polydispersity particles under given conditions. Additionally, discrete spherical particles were obtained at a low monomer concentration and/or higher polymerization temperature. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1625–1632, 2002
Structural control of oligomeric methyl silsesquioxane precursors and their thin‐film properties
Authors: Lee Long‐Hua , Chen Wen‐Chang , Liu Wei‐Chih
Published: August 2002

Oligomeric methyl silsesquioxane (O‐MSSQ) precursors were prepared from methyl trimethoxysilane (MTMS) in a mixed solvent of methyl isobutyl ketone and tetrahydrofuran by variations in the pH and molar ratio of water to MTMS (R1). The molecular structures of O‐MSSQ were controlled by the reaction conditions. At a fixed pH value, the percentage of the end group, SiOCH3, decreased with increasing R1, but that of SiOH increased. With the pH increasing, the ratio of SiOCH3 groups to SiOH groups was enhanced, but ratio of the molecular weights was reduced. The molecular weight distribution was progressively broader as the pH value decreased. These results were explained by the effects of R1 and pH on the hydrolysis and condensation reactions. The prepared O‐MSSQ precursors consisted of mixed cage and network structures. The ratio of cage structures to network structures increased at low pH and high R1 values. Highly uniform thin films were spin‐coated from the O‐MSSQ precursors, and this was followed by multistep curing. The content of cage structures in O‐MSSQ films decreased with increasing curing temperatures, whereas the network content in O‐MSSQ films showed the opposite trend. Such a structural transformation resulted in significant variations in the physical properties. Both the refractive index and dielectric constant decreased with higher cage/network ratios because of changes in the molar volume. The prepared O‐MSSQ has potential applications as a low dielectric constant material. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1560–1571, 2002
Apparent relaxation‐time spectrum cutoff in dilute polymer solutions: An effect of solvent dynamics
Authors: Peterson Steven C. , Echeverría Isabel , Hahn Stephen F. , Strand Deidre A. , Schrag John L.
Published: August 2002

The apparent short time cutoff of the relaxation‐time spectrum at surprisingly long times for polymers in solution is a well known but not yet understood observation. To elucidate its origins we revisit viscoelastic and oscillatory flow birefringence data for solutions and melts of two linear polymers (polystyrene and polyisoprene) and present new measurements of oscillatory flow birefringence of the latter. Previous measurements have suggested that the “flexibility” of both polymers in solution is smaller than in the melt on the basis of the breadth of the relaxation‐time spectrum of the solution as compared with that of the melt. Our new measurements have explored a higher effective frequency range than was previously possible. This has allowed us to observe the effect of the rotational relaxation time of the solvent on the dynamics of the solution at high frequencies. To obtain the polymer global motion contribution, one now needs to subtract from the solution properties a frequency‐dependent complex solvating environment contribution. We show that the decrease in apparent “flexibility” for solutions arises from the presence of a solvent that exhibits a rotational relaxation time and thus simple viscoelastic behavior somewhat near the frequency window of the experiment. Although recent predictions of a model for a chain in a solvent with a single relaxation time are in qualitative agreement with our results, our data suggest that the solution results may reflect the influence of solvent on the development of the “entropic spring” forces at short times. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2860–2873, 2001
Effect of thermal history on the deformation and failure of polyimides
Authors: Lincoln Jason E. , Morgan Roger J. , Shin E. Eugene
Published: August 2002

Thermal‐processing structure‐property relationships for polyetherimide (PEI), poly(4,4′‐oxydiphenylene pyromellitimide) (POPPI), and phenylethynyl‐terminated imide (PETI‐5) composite matrices are reported from a fundamental perspective. For thermoplastic PEI, deformation and failure depend primarily on free volume as evidenced by moisture‐absorption, mechanical‐property, and mass‐density changes as a function of annealing. The deformation of POPPI can be divided into the following three regimes as a function of annealing temperature: (1) physical aging‐induced glassy state free‐volume decreases, (2) thermally activated microvoid collapse, and (3) chemical degradation. In the case of PETI‐5, macroscopic defects, free volume, and polymer morphology control deformation. The effects of residual crystallinity on deformation are reported, and it is shown that mechanical toughness can be significantly decreased upon annealing below the glass‐transition temperature. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2947–2959, 2001
Water sorption and permeation in chitosan films: Relation between gas permeability and relative humidity
Authors: Despond S. , Espuche E. , Domard A.
Published: August 2002

The water sorption of chitosan has been studied at 20 °C. Water transport is governed by a Fickian process for relative humidities lower than 0.4, and in that range of partial pressures, the diffusion coefficient is concentration‐dependent. At a higher activity, anomalous diffusion is observed. The sorption isotherm is well described by the Guggenheim‐Anderson‐de Boer (GAB) model, and the clustering phenomenon observed at high relative pressures can be studied with the parameters of this model. The water permeability coefficient greatly increases with the relative pressure, and the water plasticization effect leads to a loss of the gas barrier properties under wet conditions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 3114–3127, 2001
Preparation and properties of graded styrene‐butadiene rubber vulcanizates
Authors: Ikeda Yuko
Published: August 2002

Styrene‐butadiene rubber (SBR) vulcanizates with graded network‐chain densities in the thickness direction were prepared by layering and heat pressing the compounding sheets. The effect of the gradient of network‐chain density on the mechanical properties of the graded rubber vulcanizates was investigated in comparison with those of SBR vulcanizates that were prepared from the homogeneous compounding sheets. The matrix with a high network‐chain density exclusively affected the mechanical properties of the graded rubber vulcanizates when the gradient was given in the thickness direction. © 2002 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 40: 358–364, 2002; DOI 10.1002/polb.10096
Influence of microstructure on space charges of polypropylene
Authors: Li Xiang , Du Qiangguo , Kang Jie , Tu Demin
Published: August 2002

The correlation of chemical structure, crystalline morphology, and space charge distribution under a dc electrical field was investigated with three kinds of poly(propylene) (PP) with a different chemical structure, that is, homogeneous PP and block copolymer and random copolymer of PP. The space charge distribution of the samples was prominently affected by their chemical sequence structure and crystalline microstructure. Among samples of different PPs, all isothermally crystallized at 140 °C, the sample of random coPP represents the most well proportional space charge distribution and the smallest number of space charges. The effect of thermal history on the space charge distribution was also investigated by the samples of block coPP. The sample thermally treated at 50 °C clearly represents a better proportional distribution than that at higher temperature of 140 and 100 °C. Subsequent experiments indicate that the better proportional distribution attributes to imperfect and fine sperulites with the fine distribution of the “amorphous” region. The imperfect and fine sperulites originate from the random incorporation of ethylene segments or units into PP chains or from the low annealing temperature, and play an important role in the formation of shallow traps and transportation of space charges. © 2002 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 40: 365–374, 2002; DOI 10.1002/polb.10100
Polydispersity of ethylene sequence length in metallocene ethylene/α‐olefin copolymers. I. Characterized by thermal‐fractionation technique
Authors: Zhang Fajun , Liu Jieping , Fu Qiang , Huang Haiying , Hu Zhijun , Yao Shuang , Cai Xiuyu , He Tianbai
Published: August 2002

In this article, the polydispersity of the ethylene sequence length (ESL) in ethylene/α‐olefin copolymers was studied by atomic force microscopy (AFM) and the thermal‐fractionation technique. The crystal morphology observation by AFM showed that morphology changed gradually with decreasing average ESL from complete lamellae over shorter and more curved lamellae to a granular‐like morphology, and the mixed morphology was observed after stepwise crystallization from phase‐separated melt. This result indicated that the ethylene sequence with different lengths crystallized into a crystalline phase with a different size and stability at the copolymer systems. The thermal‐fractionation technique was used to characterize the polydispersity of ESL. Three of the following statistical terms were introduced to describe the distribution of ESL and the lamellar thickness: the arithmetic mean L̄n, the weight mean L̄w, and the broadness index I = L̄w/L̄n. It was concluded that the polydispersity of ESL could be quantitatively characterized by the thermal‐fractionation technique. The effects of temperature range, temperature‐dependent specific heat capacity Cp of copolymer, and the molecular weight on the results of thermal fractionation were discussed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 813–821, 2002
Dynamic mechanical and dielectric properties of ORMOCER® incorporating functionalized poly(styrene) latexes
Authors: Cramer S. E. , Quijada‐Garrido I. , Ulrich R. , Barrales‐Rienda J. M. , Spiess H. W.
Published: August 2002

Organically modified aluminosilicate hybrid materials incorporating polystyrene and poly(styrene‐co‐hydroxypropyl acrylate) latexes, (3‐glycidyloxypropyl) trimethoxysilane, and aluminum sec‐butoxide [Al(OsBu)3] were synthesized by a sol–gel process. The bulk materials obtained were macroscopically homogeneous dispersions with good mechanical properties. Dynamic mechanical and dielectric analyses of these new hybrid materials as a function of the Al(OsBu)3 concentration and copolymer composition revealed a series of transitions that represented relaxation processes of the incorporated polymer (glass transition), AlOSi, the SiOSi part of the network, and segmental motion of unreacted Si(CH2)3OCH2CHCH2O chains. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 860–867, 2001
Low‐income women with early‐stage breast cancer: physician and patient decision‐making styles
Authors: McVea Kristine L.S.P. , Minier William C. , Johnson Palensky Jodi E.
Published: August 2002

Background: Poor women have low rates of breast conservation therapy not explained by differences in insurance status or treatment preferences. The purpose of this study was to explore how low‐income women make decisions about breast cancer treatment.

Methods: Twenty‐five women diagnosed with early‐stage breast cancer through the Nebraska Every Woman Matters program were interviewed about their experiences selecting treatment options. These interviews were transcribed and then analysed using established qualitative techniques.

Results: More than half of the women (n=16) described playing a passive role in decision making. Choice was determined by medical factors or not offered by their physicians. Intense emotional distress affected some women's ability to compare options. The women who did engage in a rational decision‐making process (n=9) based their choices on concerns about body image and fear of recurrence.

Conclusions: When presented with a choice, and when able to objectively weigh treatment options, low‐income women base their treatment decisions on the same issues as those of higher income. Whether differences in income strata alter the doctor–patient power dynamic in favor of physician control over decision making, or whether low‐income women are less prepared to engage in a rational deliberative process warrants further study. Copyright © 2001 John Wiley & Sons, Ltd.
Married couples' perspectives on prostate cancer diagnosis and treatment decision‐making
Authors: Boehmer Ulrike , Clark Jack A.
Published: August 2002

Prostate cancer is a disease of men. But for married men, it is commonly and quite reasonably expected that their wives will be significantly involved in dealing with the disease and its treatment. Yet, there are few data on how wives perceive the diagnosis and their role in responding to it. This study explores men's and their wives' perceptions of the prostate cancer diagnosis and their role in treatment decision‐making. We conducted separate focus group interviews with seven married men with metastatic prostate cancer and their wives. The accounts of receiving the diagnosis and deciding on treatment that were told by the men differed in significant ways from the stories told in the wives' groups. We found that many men do not share their prostate‐related health problems with their wives and some men choose their treatment without much spousal consideration. Our findings suggest that physicians may be in a position to influence how men and their wives interact in reaching a treatment decision. Copyright © 2001 John Wiley & Sons, Ltd.
Predictors of depressive symptomatology of geriatric patients with lung cancer—a longitudinal analysis
Authors: Kurtz M.E. , Kurtz J.C. , Stommel M. , Given C.W. , Given B.
Published: August 2002

Background: Lung cancer is a major health problem throughout the world. It is the leading cause of cancer‐related death in men and women in the USA, with a 5‐year survival rate of only 14%. It has been hypothesized that variables such as physical and social functioning, cancer‐related symptomatology, comorbid conditions, cell type, and treatment are valid predictors of the psychological response to a diagnosis of lung cancer.

Methods: As part of a larger longitudinal study, 211 patients, 65 years of age or older, with an incident diagnosis of lung cancer, were recruited from 23 sites within a midwestern state. Repeated measures analysis of variance techniques were used to analyse how age, gender, comorbid conditions, stage of disease, cell type, as well as the time‐dependent variables symptoms, physical functioning, social functioning, and treatment predict depressive symptomatology at four assessments over the first year following diagnosis.

Results: Social functioning (p<0.0001), symptoms severity (p<0.0001) and radiation treatment (p=0.017) were significant predictors of depressive symptomatology, with more symptoms and more restricted social functioning generally corresponding to higher levels of depressive symptomatology. Patients who had not received radiation treatment were more depressed than those who had received treatment at least 40 days prior to the interview.

Conclusions: At a clinical level of patient care, these findings mandate early identification of psychosocial difficulties experienced, an individualized symptom management plan and the application of other interventions, such as information giving, reassurance and referral to other resources. Copyright © 2002 John Wiley & Sons, Ltd.
Safety of inhaled corticosteroids in children
Authors: Allen David B.
Published: August 2002

Inhaled corticosteroids (ICS) are now first‐line therapy for persistent asthma in children. The major safety concerns of long‐term ICS therapy for childhood asthma are potential effects on adrenal function, growth, and bone mass. Dosage, type of inhaler device, and individual drug characteristics influence systemic effects of ICS. Sensitive measures of basal adrenal function can show statistically significant changes during ICS therapy, but these do not accurately predict clinically meaningful adrenal axis suppression. Adrenal insufficiency is rare and confined to children receiving high doses of ICS. Dose‐related inhibition of growth has been seen in some short‐ and intermediate‐term studies, but long‐term studies have found no detrimental effect on final height. ICS therapy has not been associated with significant changes in measurements of bone and bone biomarkers, but more studies of high doses and of therapy in adolescents are needed. Overall, although ICS are the most effective anti‐inflammatory treatment available for asthma, high doses of ICS in children are still of concern. The risk of high doses is compounded in children with concomitant allergic conditions that require multiple forms of topical corticosteroids. Benefits of ICS clearly outweigh potential adverse effects and risks associated with poorly controlled asthma. Risk can be minimized by using the lowest effective ICS dose, limiting systemic availability of the drug through proper technique to minimize swallowed drug, and selection of agents with efficient first‐path hepatic inactivation of swallowed drug. Adjuvant treatments can reduce the dose of ICS required for asthma control, allowing a reduction in overall systemic exposure for most children with mild‐to‐moderate persistent asthma. Therefore, these agents should be added to, but should not replace, ICS therapy. Pediatr Pulmonol. 2002; 33:208–220. © 2002 Wiley‐Liss, Inc.
Effect of intravenous antibiotics on exercise tolerance (3‐min step test)) in cystic fibrosis*
Authors: Pike Sarah E. , Prasad S. Ammani , Balfour‐Lynn Ian M.
Published: August 2002

Most children with cystic fibrosis (CF) feel better and display more energy after a course of intravenous antibiotics (IVABs), but this is not always reflected by a satisfactory improvement in lung function. We assessed the change in exercise tolerance after treatment with IVABs usingthe 3‐min step test, and compared it with changes in spirometric lung function and arterial oxygen saturation (SaO2). Thirty‐six children (mean age, 13.8 years) were enrolled from two tertiary CF centers during an inpatient stay for IVABs.

After 10–14 days of treatment, there was a significant improvement in median FEV1 from 43% to 57% of predicted values (P < 0.0001), and median FVC from 66% to 73% of predicted values (P < 0.0001), while median SaO2 significantly increased from 95% to 96.5% (P < 0.05). This was accompanied by a reduction in resting heart rate (median 118 bpm to 109 bpm, P < 0.005) and subjective breathlessness at rest (median visual analogue score 2.2 to 0.8, P < 0.005). All outcomes of exercise tolerance were improved after IVABs. There was a reduction in maximum heart rate (median 156 bpm to 150 bpm, P < 0.05) and an increase in minimum SaO2 (median 93.5% to 94.5%, P = 0.08) measured during the step test.

There was also a reduction in subjective breathlessness (median visualanalogue score of 5.5 to 4.2, P < 0.005) and objective breathlessness (median 15‐count score of 3 to 2, P < 0.0001) measured immediately after the step test.

Exercise testing was a useful outcome measure for monitoring effectiveness of inpatient therapy, and complemented spirometry and SaO2 monitoring. The simple ward‐based 3‐min step test was found to be a particularly suitable method for measuring changes in exercise tolerance in childrenwith CF. Pediatr Pulmonol. 2001; 32:38–43. © 2001 Wiley‐Liss, Inc.
Molecular characterization of prostate hyperplasia in prolactin‐transgenic mice by using cDNA representational difference analysis*
Authors: Dillner Karin , Kindblom Jon , Flores‐Morales Amilcar , Pang See‐Tong , Törnell Jan , Wennbo Håkan , Norstedt Gunnar
Published: August 2002

BACKGROUND

Transgenic mice overexpressing the rat prolactin (PRL) gene develop a dramatic enlargement of the prostate gland. The objective of this study was to characterize the molecular mechanisms in the prostate of importance for the prostate hyperplasia seen in these transgenic mice.

METHODS

cDNA representational difference analysis (cDNA RDA) was used to isolate differentially expressed transcripts in the prostate hyperplasia of the transgenic mice compared with wildtype littermates. Furthermore, cDNA microarray analysis was used to verify the RDA output.

RESULTS

Here we report 10 transcripts, some of them described to be involved in proliferation and apoptosis, which are differentially expressed in the enlarged transgenic prostates compared with controls.

CONCLUSION

The identified differentially expressed transcripts presented herein supports molecular similarities between the prostate hyperplasia of PRL‐transgenic mice and human BPH that may contribute to explain the molecular basis of prostate hyperplasia. Prostate 52:139–149, 2002. © 2002 Wiley‐Liss, Inc.
Identification of a novel gene on chromosome 13 between BRCA‐2 and RB‐1
Authors: Schmidt U. , Fiedler U. , Pilarsky C.P. , Ehlers W. , Füssel S. , Haase M. , Faller G. , Sauter G. , Wirth M.P.
Published: August 2002

METHODS AND RESULTS

By differential display we isolated a new cDNA‐fragment, named C13, that is downregulated in malignant prostate tissues. Northern hybridization revealed the fragment to be part of 3.0 and 4.4 kb mRNAs. Fluorescence in situ hybridization, Southern blotting and radiation hybrid mapping demonstrated a chromosomal localization of C13 on 13q12–14 closest to the SHGC‐34125 marker. In the 5% chromosomal environment of C13 we detected changes of the allelic status in 13 of 21 prostate cancers. A downregulation was detected at the mRNA level in patients with advanced carcinoma. The 3.0 kb full length cDNA clone encodes a protein with an open reading frame of 2,202 bp or 733 amino acids. The corresponding protein contains a putative nuclear localization signal, several glutamine clusters and an α‐helix‐rich domain. By in situ RNA hybridization we could demonstrate the mainly epithelial expression of the C13 mRNA in prostatic tissue.

CONCLUSIONS

The localization of C13 between the tumor supressor genes BRCA‐2 and RB‐1, the detected allelic imbalances, the downregulation of its mRNA in some prostatic cancer tissues, the epithelial expression and the described protein structure suggest that this gene encodes a protein that may have tumor or metastasis suppressing function in prostate tissue. Prostate 47:91–101, 2001. © 2001 Wiley‐Liss, Inc.
Proliferative activity and branching morphogenesis in the human prostate: A closer look at pre‐ and postnatal prostate growth
Authors: Xue Yong , Sonke Gabe , Schoots Coen , Schalken Jack , Verhofstad Albert , Rosette Jean de la , Smedts Frank
Published: August 2002

Background

To gain further insight into the molecular cell biologic features of prostate development, we investigated the proliferative activity of prostate epithelial and stromal cells and their topographic relationship with neuroendocrine (NE) cell distribution and regional heterogeneity.

Methods

Consecutive sections from 43 prostates taken during autopsy representing fetuses (12–38 weeks of gestation), infants, prepubertal males and adults were double stained for chromogranin A and MIB‐1. MIB‐1 labeling index (LI) was calculated in the budding tips, forming acini, major collecting ducts, adjacent and non‐adjacent stromal compartments. Furthermore, the topographic relationship between proliferating cells and NE cells was evaluated.

Results

In the first half of gestation, cell proliferation as revealed by MIB‐1 LI was significantly higher in epithelial structures and stroma than in older fetuses and other age groups. MIB‐1 LI was higher in budding tips than in other epithelial regions. MIB‐1 LI in stroma adjacent to budding tips was not higher than that adjacent to other epithelial branching segments. Co‐expression of chromogranin A and MIB‐1 staining was not observed. MIB‐1 LI was lower in cells in the direct vicinity of chromogranin A positive NE cells than at a distance from NE cells.

Conclusions

Prostate development in the first half of gestation is explosive. Thereafter, the prostate basically is a slow‐growing organ. Budding tips are the major growth foci during early prostate development, while stromal growth is evenly distributed throughout the prostate, probably indicating that stromal‐epithelial interactions do not manifest in enhanced proliferation at their interface. NE cells may have an inhibitory effect on proliferation of exocrine epithelial cells and are probably only associated with differentiation of prostate exocrine cells in the prostate. Prostate 49:132–139, 2001. © 2001 Wiley‐Liss, Inc.
Protein docking using a genetic algorithm
Authors: Gardiner Eleanor J. , Willett Peter , Artymiuk Peter J.
Published: August 2002

A genetic algorithm (GA) for protein–protein docking is described, in which the proteins are represented by dot surfaces calculated using the Connolly program. The GA is used to move the surface of one protein relative to the other to locate the area of greatest surface complementarity between the two. Surface dots are deemed complementary if their normals are opposed, their Connolly shape type is complementary, and their hydrogen bonding or hydrophobic potential is fulfilled. Overlap of the protein interiors is penalized. The GA is tested on 34 large protein–protein complexes where one or both proteins has been crystallized separately. Parameters are established for which 30 of the complexes have at least one near‐native solution ranked in the top 100. We have also successfully reassembled a 1,400‐residue heptamer based on the top‐ranking GA solution obtained when docking two bound subunits. Proteins 2001;44:44–56. © 2001 Wiley‐Liss, Inc.
Successful molecular dynamics simulation of two zinc complexes bridged by a hydroxide in phosphotriesterase using the cationic dummy atom method
Authors: Pang Yuan‐Ping
Published: August 2002

I report herein two 2.0 ns (1.0 fs time step) MD simulations of two zinc complexes bridged by a hydroxide in phosphotriesterase (PTE) employing the nonbonded method and the cationic dummy atom method that uses virtual atoms to impose orientational requirement for zinc ligands. The cationic dummy atom method was able to simulate the four‐ligand coordination of the two zinc complexes in PTE. The distance (3.39 ± 0.07Å) between two nearby zinc ions in the time‐average structure of PTE derived from the MD simulation using the cationic dummy atoms matched that in the X‐ray structure (3.31 ± 0.001Å). Unequivocally, the time‐average structure of PTE was able to fit into the experimentally determined difference electron density map of the corresponding X‐ray structure. The results demonstrate the practicality of the cationic dummy atom method for MD simulations of zinc proteins bound with multiple zinc ions. In contrast, a 2.0 ns (1.0 fs time step) MD simulation using the nonbonded method revealed a striking difference in the active site between the X‐ray structure and the time‐average structure that was unable to fit into the density map of PTE. The results suggest that caution should be used in the MD simulations using the nonbonded method. Proteins 2001;45:183–189. © 2001 Wiley‐Liss, Inc.
Revisiting the structural flexibility of the complex p21ras‐GTP: The catalytic conformation of the molecular switch II
Authors: Soares T.A. , Miller J.H. , Straatsma T.P.
Published: August 2002

The hydrolysis of GTP in p21ras triggers conformational changes that regulate the ras/ERK signaling pathway. An important active site residue is Gln61, which has been found to be mutated in 30% of human tumors. The dynamics of the active site conformation is studied by using molecular dynamics simulation of two independent structures of the GTP‐bound uncomplexed enzyme. Two distinct conformations of the enzyme are observed, in which the side‐chain residue Gln61 is in different orientations. Essential dynamics analysis is used to describe the essential motions in the transition between the two conformations. Results are compared with earlier simulations of p21ras and its complex with GTPase activating protein p21‐GAP. Proteins 2001;45:297–312. © 2001 Wiley‐Liss, Inc.
Insect growth inhibition, antifeedant and antifungal activity of compounds isolated/derived from Zingiber officinale Roscoe (ginger) rhizomes
Authors: Agarwal Manjree , Walia Suresh , Dhingra Swaran , Khambay Bhupinder P S
Published: August 2002

Fresh rhizomes of Zingiber officinale (ginger), when subjected to steam distillation, yielded ginger oil in which curcumene was found to be the major constituent. The thermally labile zingiberene‐rich fraction was obtained from its diethyl ether extract. Column chromatography of ginger oleoresin furnished a fraction from which [6]‐gingerol was obtained by preparative TLC. Naturally occurring [6]‐dehydroshogaol was synthesised following condensation of dehydrozingerone with hexanal, whereas zingerone and 3‐hydroxy‐1‐(4‐hydroxy‐3‐methoxyphenyl)butane were obtained by hydrogenation of dehydrozingerone with 10% Pd/C. The structures of the compounds were established by 1H NMR, 13C NMR and mass (EI‐MS and ES‐MS) spectral analysis. The test compounds exhibited moderate insect growth regulatory (IGR) and antifeedant activity against Spilosoma obliqua, and significant antifungal activity against Rhizoctonia solani. Among the various compounds, [6]‐dehydroshogaol exhibited maximum IGR activity (EC50 3.55 mg ml −1) while dehydrozingerone imparted maximum antifungal activity (EC50 86.49 mg litre−1).

© 2001 Society of Chemical Industry