bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction of the Korea Elderly Pharmacoepidemiologic Cohort: drug utilization review of cephalosporins in geriatric inpatients
Authors: Park Byung Joo , Cho Yong Kyun , Kim Sun Ah
Published: August 2002

We performed a cohort‐based pharmacoepidemiologic study in order to evaluate the pattern of cephalosporin prescriptions in elderly inpatients in Korea. The Korea Elderly Pharmacoepidemiologic Cohort was composed of a geriatric population of beneficiaries of the Korea Medical Insurance Corporation residing in Busan in 1993. The cohort consisted of 23 649 members, comprising 15 221 women (64.4%) and 8428 men (35.6%). The study population for drug utilization review consisted of those cohort members who were admitted into hospitals during the period January 1993 through December 1994. The number of hospitalized patients was 4262, comprising 2631 women (61.7%) and 1681 men (38.3%). The trend of cephalosporin prescriptions over the 2‐year period showed that the use of second and third generation cephalosporins increased relative to the use of first generation. The use of cephalosporins combined with other antibiotics was found to occur in 22.8% aminoglycosides (76.7%) and quinolones (17.1%) being the most common antibiotics combined with cephalosporins. Our result demonstrates an increase in the prescription of second and third generation cephalosporins in Korea, which has implications not only for the elderly population but also for the total population because of the impact on health care costs and the potential for the emergence of antimicrobial resistance. Copyright © 2001 John Wiley & Sons, Ltd.
Use of proportional reporting ratios (PRRs) for signal generation from spontaneous adverse drug reaction reports
Authors: Evans S. J. W. , Waller P. C. , Davis S.
Published: August 2002

Background

The process of generating ‘signals’ of possible unrecognized hazards from spontaneous adverse drug reaction reporting data has been likened to looking for a needle in a haystack. However, statistical approaches to the data have been underutilised.

Methods

Using the UK Yellow Card database, we have developed and evaluated a statistical aid to signal generation called a Proportional Reporting Ratio (PRR). The proportion of all reactions to a drug which are for a particular medical condition of interest is compared to the same proportion for all drugs in the database, in a 2 × 2 table. We investigated a group of newly‐marketed drugs using as minimum criteria for a signal, 3 or more cases, PRR at least 2, chi‐squared of at least 4.

Findings

The database was used to examine retrospectively 15 drugs newly‐marketed in the UK, with the highest levels of ADR reporting. The method identified 481 signals meeting the minimum criteria during the period 1996–8. Further evaluation of these showed that 70% were known adverse reactions, 13% were events which were likely to be related to the underlying disease and 17% were signals requiring further evaluation.

Implications

Proportional reporting ratios are a valuable aid to signal generation from spontaneous reporting data which are easy to calculate and interpret, and various refinements are possible. © Crown copyright 2001. Reproduced with the permission of Her Majesty's Stationary Office. Published by John Wiley & Sons, Ltd.
Influence of the COOH and COONa groups and crosslink density of poly(acrylic acid)/montmorillonite superabsorbent composite on water absorbency
Authors: Wu Jihuai , Lin Jianming , Li Guoqing , Wei Congrong
Published: August 2002

A novel poly(acrylic acid)/montmorillonite superabsorbent composite with a water absorbency of 1100 times its own weight was synthesized by the graft copolymerization of acrylic acid with a cross‐linking agent in the presence of montmorillonite ultrafine powder. The influence of the amount of crosslinker and montmorillonite on water absorbency has been investigated. It was found that a crosslinker concentration of 0.03 wt% and 30 wt% montmorillonite gave the best results. The collaborative absorbent effect of sodium carboxylate and carboxylic acid groups was superior to that of sodium carboxylate or carboxylic acid groups alone, and the composite with a ratio of about 2/3 for sodium carboxylate to carboxyl acid groups possessed the highest water absorbence.

© 2001 Society of Chemical Industry
Crosslinked chitosan membranes: characterization and study of dimethylhydrazine dehydration by pervaporation
Authors: Sridhar S , Susheela G , Reddy G Jayasimha , Khan A A
Published: August 2002

Crosslinked chitosan membranes were synthesized using glutaraldehyde and characterized by infra‐red (IR) and wide‐angle X‐ray diffraction (WAXD) spectroscopic methods. The membranes were applied for the pervaporation‐based dehydration of the highly hazardous and hypergolic unsymmetrical dimethylhydrazine liquid propellant. The characterization techniques were an efficient tool in identifying polymer–liquid interaction sites and the separation mechanisms involved. The crosslinked polymer was found to have good potential for the separation of the aqueous azeotrope of the propellant (20 wt%) and its enrichment to >90% purity. An equilibrium sorption study examined the preferential affinity of the membrane amongst the two penetrating liquids. The pervaporation performance of the membrane was evaluated by varying the experimental parameters of feed composition, membrane thickness and permeate pressure, and found to be promising.

© 2001 Society of Chemical Industry
Synthesis, characterization and thermal properties of phenylene–disiloxane polymers obtained from catalytic cross‐dehydrocoupling polymerization of bis(dimethylsilyl)benzene isomers and water
Authors: Kawakita Takahiko , Oh Hyun‐Shik , Moon Jeong‐Yeol , Liu Yang , Imae Ichiro , Kawakami Yusuke
Published: August 2002

Phenylene–disiloxane polymers were prepared from 1,4‐bis(dimethylsilyl)benzene and 1,3‐bis(dimethylsilyl)benzene with water in various ratios by catalytic cross‐dehydrocoupling polymerization. Each isomer showed almost equal reactivity in the polymerization as verified by the analysis of the composition by
1H NMR. Crystallinity observed in the polymer obtained from the 1,4‐isomer was removed by incorporating a small amount of 1,3‐isomer.

© 2001 Society of Chemical Industry
Effect of 1,1′‐dibenzyl‐4,4′‐bipyridyl dichloride (DBD) on charge‐conduction process and photovoltaic response of a polypyrrole (PPy) thin‐film device
Authors: Roy M S , Manmeeta  , Jaiswal Pratibha , Sharma G D
Published: August 2002

The present communication deals with analysing the effect of 1,1′‐dibenzyl‐4,4′‐bipyridyl dichloride (DBD) substitution at the N‐position of 2,5‐polypyrrole (PPy), on electrical, impedance and photovoltaic properties. The thin‐film device was fabricated by sandwiching DBD‐substituted PPy between indium tin oxide (ITO) and aluminium (Al) electrodes. The formation of a Schottky barrier with Al and ohmic contact with ITO are explained in terms of p‐type semiconducting behaviour of DBD‐substituted PPy. In the low‐voltage region, Ohm's law is followed, while in the high‐voltage region, a space‐charge‐limited conduction (SCLC) controlled by the exponential‐trap distribution was observed. DBD substitution causes shifting of the Fermi level towards the valence‐band edge and an increase in charge‐carrier mobility. A remarkable change in dark electrical conductivity of the order of five has been observed in DBD‐substituted PPy. The electrical and impedance measurements of an ITO/PPy:DBD/Al device confirms the formation of a Schottky barrier at the DBD‐substituted PPy/Al interface. Additionally, it can be modelled by a simple equivalent circuit of two resistance–capacitance (RC) elements in series representing the bulk and a junction‐region. At low frequency, the device capacitance follows a pronounced voltage dependence. From a detailed analysis of the J–V and C–V characteristics, the ionized acceptor concentration (Na), width of depletion layer (W) and potential barrier height (ϕb) have been evaluated. We observed a significant enhancement in photocurrent on DBD substitution. The increase in photocurrent is explained by the efficient charge separation induced by the intermolecular transfer of photo‐excited electrons from PPy to DBD. The substitution also causes a reduction in the trapping centres in the material.

© 2002 Society of Chemical Industry
Structural and physicochemical characterization of hemicelluloses isolated by alkaline peroxide from barley straw
Authors: Sun RunCang , Sun X F , Liu G Q , Fowler P , Tomkinson J
Published: August 2002

Seven hemicellulosic preparations were obtained from barley straw by extraction with 1.5% H2O2 at pH 12.0 for 14 h at 45 °C with extractant to straw ratios of 10:1, 13:1, 15:1, 18:1, 20:1, 25:1 and 30:1. The respective yields of dissolved hemicelluloses were 28.4 wt%, 28.8 wt%, 29.7 wt%, 30.1 wt%, 30.6 wt%, 30.8 wt% and 30.8 wt% or dry barley straw, corresponding to release of 78.7%, 79.8%, 82.3%, 83.4%, 84.8%, 85.3% and 85.3% of the original hemicelluloses. The polymers were mainly composed of xylose, arabinose, glucose, galactose and 4‐O‐methyl‐D‐glucuronic acid (59.3–62.6%, 19.7–22.0%, 8.8–12.5%, 5.6–6.9% and 5.8–6.7%, respectively) and had weight‐average molecular weights of between 38 470 and 41 050 g mol−1.13 CNMR spectroscopy confirmed the results obtained by chemical methods, and showed that the hemicellulosic fraction was mostly by L‐arabino‐(4‐O‐methyl‐D‐glucurono)‐D‐xylan. More importantly, it was found that lignin provides some protection for the hemicelluloses in barley straw against attack by hydrogen peroxide.

© 2002 Society of Chemical Industry
Solar home system battery and charge regulator testing
Authors: Díaz Pablo , Lorenzo Eduardo
Published: August 2002

Laboratory testing procedures for solar home system batteries and charge regulators are proposed, as a follow up to the Universal Technical Standard for Solar Home Systems, presented in 1998. Procedures, definition and selection of instrumentation have paid particular attention to simplicity, in order to facilitate their application not only in sophisticated laboratories of industrialised countries, but also in local environments and laboratories of developing countries. On the other hand, test results from a measurement programme performed on 8 different batteries and 20 different charge regulators are presented and discussed. Finally, a review for up‐dating the technical standard is presented, based on field and laboratory experience. Copyright © 2001 John Wiley & Sons, Ltd.
Synthesis of multi‐porphyrin arrays and study of their self‐assembly behaviour at the air–water interface
Authors: Foekema Jantien , Schenning Albertus P. H. J. , Vriezema Dennis M. , Benneker Franciscus B. G. , Nørgaard Kasper , Kroon Johannes K. M. , Bjørnholm Thomas , Feiters Martinus C. , Rowan Alan E. , Nolte Roeland J. M.
Published: August 2002

A series of multi‐porphyrin arrays were synthesized and the self‐assembly behaviour of these compounds at the air–water interface was investigated by the Langmuir–Blodgett technique. It was found that as the overall area of the porphyrin molecules was increased, upon going from a mono‐ to bis‐ to a tetra‐ and then to hexaporphyrin species, the intermolecular stacking between the molecules also increases, resulting in more stable monolayers. In the case of the hexaporphyrin species the intermolecular interactions are so strong that monolayer formation is irreversible. All porphyrin monolayers can be transferred to a glass surface with good transfer ratios, leading to highly ordered porphyrin films in which the chromophores are arranged orthogonal to the glass surface. Copyright © 2001 John Wiley & Sons, Ltd.
Chemical‐surface modification of polymers using atmospheric pressure nonequilibrium plasmas and comparisons with vacuum plasmas
Authors: Shenton M. J. , Stevens G. C. , Wright N. P. , Duan X.
Published: August 2002

We demonstrate that stable microwave‐coupled atmospheric pressure nonequilibrium plasmas (APNEPs) can be formed under a wide variety of gas and flow‐rate conditions. Furthermore, these plasmas can be effectively used to remove surface contamination and chemically modify polymer surfaces. These chemical changes, generally oxidation and crosslinking, enhance the surface properties of the materials such as surface energy. Comparisons between vacuum plasma and atmospheric plasma treatment strongly indicate that much of the vacuum‐plasma literature is pertinent to APNEP, thereby providing assistance with understanding the nature of APNEP‐induced reactions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 95–109, 2002
Substituent effects on the polycondensation of quinones with aromatic amines to form poly(quinone imine)s
Authors: Dibattista James , Schmidt Brian M. , Buyle Padias Anne , Hall H. K.
Published: August 2002

The effect of alkyl groups on the polycondensation of aromatic diamines and quinones to form poly(quinone imine)s was investigated. Models were synthesized under standard conditions: 1 equiv of quinone was reacted with 2 equiv of aniline in the presence of titanium tetrachloride and 1,4‐diazabicyclo[2.2.2]octane. Only modest yields of diimines were obtained when alkyl substituents were introduced. Likewise, alkyl substituents were harmful in the polycondensation of both anthraquinones and benzoquinones with aromatic diamines. As for fluorine substituents, model reactions with either 1,5‐difluoroanthraquinone or 1,4‐difluoroanthraquinone with aniline proceeded in high yields. These model compounds for aromatic poly(quinone imine)s were characterized with 1H NMR spectroscopy, 19F NMR spectroscopy, variable‐temperature 1H NMR spectroscopy, and X‐ray crystal structure determination. Polymers of the difluoroanthraquinones with aromatic diamines were obtained in high yields, although not in high molecular weights, and no stereocontrol was found. Both p‐benzoquinones and anthraquinones were used as monomers in these polymerizations, and a fundamental difference in reactivity was observed. With the former, the polymerization behaved as a classical polycondensation and demanded exact reagent equivalence. With the anthraquinones, however, the polymerization proceeded by a condensation chain polymerization and was much more forgiving. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 43–54, 2002
Synthesis and characterization of soluble polyimides derived from 2,2′‐Bis(3,4‐dicarboxyphenoxy)‐9,9′‐spirobifluorene dianhydride
Authors: Reddy D. Sahadeva , Shu Ching‐Fong , Wu Fang‐Iy
Published: August 2002

The synthesis of aromatic poly(ether imide)s containing spirobifluorene units in the polymer backbone is described. 2,2′‐Bis(3,4‐dicarboxyphenoxy)‐9,9′‐spirobifluorene dianhydride, which was used as a new monomer, was synthesized with 2,2′‐dihydroxy‐9,9′‐spirobifluorene as the starting material. In the spiro‐segment, the rings of the connected bifluorene were orthogonally arranged. This bis(ether anhydride) monomer was employed in reactions with a variety of aromatic diamines to furnish poly(ether imide)s, involving an initial ring‐opening polycondensation and subsequent chemically induced cyclodehydration. Excellent solubility in common organic solvents at room temperature, good optical transparency, and high thermal stability are the prominent characteristic features of these new polymers, which can be attributed to the presence of spiro‐fused orthogonal bifluorene segments along the polymer chain. The glass‐transition temperatures of the polyimides were 240–293 °C, and the 5% weight‐loss temperatures were greater than 500 °C. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 262–268, 2002
Polyesters by lipase‐catalyzed polycondensation of unsaturated and epoxidized long‐chain α,ω‐dicarboxylic acid methyl esters with diols
Authors: Warwel Siegfried , Demes Christoph , Steinke Georg
Published: August 2002

Long‐chain, symmetrically unsaturated α,ω‐dicarboxylic acid methyl esters (C18, C20, C26) were obtained by the catalytic metathetical condensation of 9‐decenoic, 10‐undecenoic, and 13‐tetradecenoic acid methyl esters, respectively, with the homogeneous Grubbs catalyst bis(tricyclohexyl phosphine) benzylidene ruthenium dichloride dissolved in methylene chloride. The dicarboxylic acid esters were epoxidized chemoenzymatically with H2O2/methyl acetate with Novozym 435®, an immobilized lipase B from Candida antarctica. Polyesters from symmetrically unsaturated or epoxidized α,ω‐dicarboxylic acid methyl esters with 1,3‐propanediol or 1,4‐butanediol, respectively, were achieved by enzymatic polycondensation with the same biocatalyst applied. With 1,3‐propanediol as a substrate, the linear unsaturated and epoxidized polyesters had molecular weights of 1950–3300 g/mol and melting points of 47–75 °C, whereas with 1,4‐butanediol as a substrate, the resulting polyesters showed higher molecular weights, 7900–11,600 g/mol, with similar melting points of 55–74 °C. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1601–1609, 2001
Molecular dynamics in nanostructured polyimide–silica hybrid materials and their thermal stability
Authors: Bershtein V. A. , Egorova L. M. , Yakushev P. N. , Pissis P. , Sysel P. , Brozova L.
Published: August 2002

Molecular motion and thermal stability in two series of nanophase‐separated polyimide–silica (PI–SiO2) hybrid materials with chemically bound components were studied. The hybrids were synthesized from p‐aminophenyltrimethoxysilane‐terminated poly(amic acid)s as PI precursors and tetramethoxysilane as a silica precursor via a sol–gel process. The hybrids differed in their PI chemical structure and chain length (number‐average molecular weight = 5.000, 7.500, or 10.000) and in their SiO2 content, which ranged from 0 to 50 wt %. Differential scanning calorimetry, laser‐interferometric creep rate spectroscopy, and thermally stimulated depolarization current techniques were used for studying the dynamics from 100 to 650 K and from 10−3 to 10−2 Hz. Comparative thermogravimetric measurements were also carried out from 300 to 900 K. Silica nano‐ or submicrodomains that formed affected PI dynamics in two opposite directions. Because of the loosening of the molecular packing of PI chains confined to nanometer‐scale spaces between silica constraints, an enhancement of small‐scale motion, mostly at temperatures below the β‐relaxation region, occurred. However, a partial or total suppression of segmental motion could be observed above the β‐relaxation temperature, drastically so for the shortest PI chains at elevated silica contents and within or close to the glass‐transition range, because of the covalent anchoring of chain ends to silica domains. Large changes in thermal stability, including a 2.5‐fold increase in the apparent activation energy of degradation, were observed in the hybrids studied. A greater than 100 °C rise in long‐term thermal stability could be predicted for some hybrids with respect to pure PI. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1056–1069, 2002
Miscible blends of nitro‐substituted polybenzimidazole and polyetherimide
Authors: Cho Junhan , Park Min Su , Choi Jin Hyun , Ji Byung Chul , Han Sung Soo , Lyoo Won Seok
Published: August 2002

A novel blend system was prepared by blending organosoluble nitro‐substituted polybenzimidazole (NO2‐PBI) and polyetherimide (PEI) in a cosolvent at a moderate condition. It was shown that the NO2‐PBI/PEI blends not only possess tractable processability owing to the enhanced solubility of NO2‐PBI but also retain the desirable features of unmodified PBI/PEI blends. Apparent miscibility in the blends was observed and attributed to hydrogen‐bonding interactions between NH groups in NO2‐PBI and carbonyl groups in PEI. It was revealed that the NO2‐PBI/PEI blends phase‐separate upon heating above the glass‐transition temperatures. The observed mixing of NO2‐PBI and PEI in a molecular level, although sustainable only in the glassy region, was shown to lend synergy effects to the physical properties of the blends. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1778–1783, 2001
‘Dividing the desolation’: clients views on the benefits of a cancer counselling service
Authors: Boulton Mary , Boudioni Markella , Mossman Jean , Moynihan Clare , Leydon Geraldine , Ramirez Amanda
Published: August 2002

This paper describes clients' accounts of the benefits they derived from a short course of cancer counselling provided within a humanist framework. Three hundred and two clients who had attended at least one session of a short course of cancer counselling received an evaluation form, which incorporated both fixed‐choice and open‐ended questions. One hundred and forty two (47%) clients returned evaluation forms; those who had attended more sessions were significantly more likely to do so. Quantitative data were analysed using SPSS (Statistical Package for the Social Sciences) for Windows and qualitative data using a thematic approach. Almost all clients indicated that they felt they had benefited from counselling. Analysis of the open‐ended questions identified nine main benefits of counselling and four key avenues or processes through which clients derived these benefits. Overall, counselling was seen as helping them to work through powerful thoughts and feelings and so to come to terms with cancer and to regain a sense of control in their lives. The benefits of a short course of counselling which clients identified reflect the aims of humanistic counselling which are not well captured by psychiatric assessments or most standard research instruments. In evaluating cancer counselling services, assessments which include these client‐defined outcomes may provide a more sensitive way of gauging the value of counselling to a non‐clinic population. Copyright © 2001 John Wiley & Sons, Ltd.
Who wants second‐line, palliative chemotherapy?
Authors: Balmer Claire E. , Thomas Peter , Osborne Richard J.
Published: August 2002

This paper reports on a study designed to measure the value attached to second‐line, palliative chemotherapy by people with advanced cancer, compared with the value healthy people assume they would attach if they had cancer and to assess reasons for accepting or declining treatment. Subjects comprised 92 people with cancer, 76 healthy control subjects, 60 medical oncologists, 128 clinical oncologists, 72 palliative care physicians, 58 general practitioners and 59 qualified nurses working within oncology. Using a questionnaire presenting two typical but imaginary treatment scenarios, subjects indicated whether treatment would be acceptable to them and, if so, what minimum chance and duration of benefit would make treatment worthwhile. Demographic and social data were also collected. Patients accepted a lower chance of benefit than all other groups. Although the minimum worthwhile duration of benefit was more evenly spread, patients choosing lower time values were over‐represented. These results were consistent even when treatment involved greater toxicity. The conclusion drawn from this study is that people with advanced cancer are more willing to accept second‐line chemotherapy with a lower chance and shorter duration of benefit than others may imagine. Health care professionals must recognize this when discussing treatment options with patients. Copyright © 2001 John Wiley & Sons, Ltd.
Metal airway stent implantation in children: Follow‐up of seven children
Authors: Nicolai T. , Huber R.M. , Reiter K. , Merkenschlager A. , Hautmann H. , Mantel K.
Published: August 2002

Long segment malacia of the trachea or main stem bronchi in children is not always suitable for surgical correction; patients may therefore remain ventilator‐dependent and/or experience severe obstructive crises. We treated 7 children (ages, 4 months to 9 years) with extreme structural central airway obstruction with stent implantations. Six were mechanically ventilated; 5 had frequent life‐threatening obstructive spells requiring deep sedation or paralysis. Diagnoses were: syndrome‐associated tracheobronchomalacia (n = 4), malignancy infiltrating the carina (n = 1), congenital tracheal stenosis (n = 1), and tracheobronchial compression by a malpositioned aorta (n = 1). Six tracheal and 13 bronchial stents were endoscopically placed. The prostheses included mesh titan (n = 5), the newer shape memory material nitinol (n = 13), and 1 Y‐shaped carina stent. Follow‐up was reported for 7 weeks to 72 months.

All patients showed marked improvement of their respiratory obstruction. Six children were weaned at least temporarily from ventilation. No significant bleeding, stenosis, or perforation was observed. Seven stents were changed after up to 14 months. Three children are well and at home. In 2 children airway stabilization was successful, but they later died from causes unrelated to stent placement, and 2 children died due to generalized airway disease.

Soft metal mesh airway stents can offer a therapeutic option in life‐threatening inoperable obstruction of the trachea and main stem bronchi in children. Pediatr Pulmonol. 2001; 31:289–296. © 2001 Wiley‐Liss, Inc.
Eosinophil cationic protein in infants with respiratory syncytial virus bronchiolitis: Predictive value for subsequent development of persistent wheezing
Authors: Pifferi Massimo , Ragazzo Vincenzo , Caramella Davide , Baldini Giuliano
Published: August 2002

Infants with acute bronchiolitis during the first months of life are at increased risk of developing persistent wheezing and bronchial asthma later in life. The study of eosinophil cationic protein (ECP) suggests that eosinophil‐related inflammatory mechanisms may play a role in respiratory syncytial virus (RSV) bronchiolitis. The aim of our study was to verify whether serum ECP (s‐ECP) measurements are useful in predicting the development of persistent wheezing in children affected by RSV bronchiolitis during a 5 years follow‐up period. Forty‐eight infants were enrolled prospectively (mean age: 153.5 days). All had a clinical and radiological diagnosis of acute bronchiolitis and confirmed RSV infection. Peripheral eosinophil counts, levels of s‐ECP, and serum IgE concentrations were measured during bronchiolitis. Five years later the children were re‐evaluated in regard to their respiratory symptoms (standardized questionnaires) and atopic status (specific IgE levels).

We observed significantly higher s‐ECP levels (P < 0.001) at enrollment in subjects who developed persistent wheezing compared to subjects who did not show late wheezing. Initial s‐ECP values allowed significant and correct prediction of persistent wheezing (P < 0.001). The risk to develop respiratory symptoms was 9.73 higher for infants with s‐ECP levels ≥ 8 μg/L than for those with s‐ECP levels <8 μg/L (P < 0.0001).

In conclusion, our study suggests that s‐ECP levels in infants with bronchiolitis are useful in predicting the risk to develop wheezing in the subsequent 5 years. Pediatr Pulmonol. 2001; 31:419–424. © 2001 Wiley‐Liss, Inc.
Spirometry in children aged 3 to 5 years: Reliability of forced expiratory maneuvers*
Authors: Crenesse D. , Berlioz M. , Bourrier T. , Albertini M.
Published: August 2002

The aim of this study was to evaluate the feasibility and reproducibility of forced expiratory maneuvers during standard spirometric evaluation in preschool children. Among 570 young children attending our laboratory, we retrospectively selected 355 patients (14% 3–4‐year‐olds, 48% 4–5‐year‐olds, and 38% 5–6‐year‐olds) who carried out spirometric tests for the first time. The indications for such tests were history of asthma (70%), followed by chronic cough (20%) and other miscellaneous conditions (10%).

Eighty‐eight, 175, and 92 children performed one, two, and three acceptable tests respectively. Forced expired volume in 1 sec (FEV1) and forced vital capacity (FVC) did not differ significantly between attempts in children performing either two or three attempts. Forced expiratory time (FET), i.e., the total time required for the forced expiratory maneuver, was 1.7 ± 0.1 sec (mean ± SEM), and was no greater than 1 sec in 21.3% of all tested children. Consequently, FEV1 does not appear to be well‐suited to this age group. Forced expiratory volume in 0.50 and 0.75 sec (FEV0.5, FEV0.75) were thus measured in the group of children performing three attempts (n = 92), and there was no statistical difference between attempts. In 267 children performing two or three tests, the ATS criteria of reproducing FEV1 and FVC within ≤ 0.1 L seemed to be preferable in this young population. Indeed, more than 70% of the tested children presented their two best efforts (FVC and FEV1) not varying by more than 0.1 L. Individual coefficients of variation (CV = SD/mean×100%) over three tests for FEV1 and FVC were 6.71 ± 0.53% and 6.35 ± 0.41% (mean ± SEM), respectively.

These results show that forced expiratory tests are not always feasible in young children, but that 55% (196/355) of our selected population performed reliable maneuvers (at least two FVC and FEV1 reproducible within 0.1 L), provided that they were supervised by a carefully trained pediatric medical staff. Pediatr Pulmonol. 2001; 32:56–61. © 2001 Wiley‐Liss, Inc.
RETRACTED: Stat3 enhances the growth of LNCaP human prostate cancer cells in intact and castrated male nude mice
Authors: DeMiguel Fernando , Lee Soo Ok , Lou Wei , Xiao Xiao , Pflug Beth R. , Nelson Joel B. , Gao Allen C.
Published: August 2002

BACKGROUND

Prostate cancer frequently progresses from an initial androgen dependence to androgen independence, rendering the only effective androgen ablation therapy useless. The mechanism underlying the androgen‐independent progression is unknown. Stat3, a member of the family of signal transducers and activators of transcription, is activated in numerous cancers, including prostate. This study is to investigate the role of Stat3 activation in the growth of prostate cancer cells.

METHODS

A constitutively active Stat3 was ectopically expressed in androgen‐sensitive LNCaP prostate cancer cells and resulting stable clones expressing activated Stat3 were isolated. The effect of Stat3 activation on LNCaP cell growth in response to androgen in vitro and in vivo was examined.

RESULTS

We show that the levels of activated Stat3 are associated with the progression of androgen‐independent prostate cancer. Activation of Stat3 in androgen‐sensitive LNCaP prostate cancer cells results in enhancement of tumor growth in both intact and castrated male nude mice and enhances androgen receptor‐mediated prostate specific antigen expression.

CONCLUSIONS

These findings demonstrate that intracellular signaling mediated by Stat3 can enhance the growth of androgen‐sensitive human LNCaP prostate cancer cells in both intact and castrated male nude mice. Prostate 52:123–129, 2002. © 2002 Wiley‐Liss, Inc.
In vitro dorsal root ganglia and human prostate cell line interaction: Redefining perineural invasion in prostate cancer
Authors: Ayala Gustavo E. , Wheeler Thomas M. , Shine H. David , Schmelz Monika , Frolov Ana , Chakraborty Subhendu , Rowley David
Published: August 2002

Background

Little is understood regarding mechanisms of perineural invasion in prostate cancer progression. We present a novel model system and data that indicate perineural invasion is an active, specific, and reciprocal interaction between nerves and prostate cancer cells.

Methods

Mouse dorsal root ganglia (DRG) and human prostate cancer cells (Du‐145, LNCaP, PC3) and stromal cells (HTS‐40F) were co‐cultured in Matrigel matrix. Control cultures consisted of prostate cancer and stromal cells only and DRG only. Neurite outgrowth, cell colony growth, neurite‐colony contact, and retrograde extension were quantitated with dark phase microscopy and image analysis (Optimas 6.1).

Results

Directional outgrowth of neurites was observed projecting into DU‐145 colonies within 24 hr of co‐culture. Cultures with the greatest number of DU‐145 cells recruited significantly more neurites and established contact earlier, indicating this process was cell‐seeding density dependent. Once neurite/DU‐145 cell contact was established neurite growth diminished, suggesting an active neurite recruitment by DU‐145 cells. Subsequent to neurite contact, DU‐145 cells migrated along neurites in a retrograde fashion into the nerve/ganglion of origin (retrograde extension) establishing perineural invasion. In addition to perineural invasion, DU‐145 colony growth was elevated in DRG co‐cultures relative to DU‐145‐only control cell cultures. Similarly, the degree of neurite outgrowth was elevated in DRG‐cell co‐cultures relative to DRG‐only control cultures. The same observations were made with LNCaP and PC3 cells, but interactions between stromal cells and nerves were not found.

Conclusions

This study shows the utility of the prostate cancer/DRG in vitro system to study specific mechanism of prostate cancer cell‐nerve interaction. Morever, these data suggest that perineural invasion mechanisms involve active and reciprocal interactions between carcinoma cells and adjacent nerve/ganglions in prostate cancer progression. Prostate 49:213–223, 2001. © 2001 Wiley‐Liss, Inc.
Combining mutations in HIV‐1 protease to understand mechanisms of resistance
Authors: Mahalingam Bhuvaneshwari , Boross Peter , Wang Yuan‐Fang , Louis John M. , Fischer Christopher C. , Tozser Jozsef , Harrison Robert W. , Weber Irene T.
Published: August 2002

HIV‐1 develops resistance to protease inhibitors predominantly by selecting mutations in the protease gene. Studies of resistant mutants of HIV‐1 protease with single amino acid substitutions have shown a range of independent effects on specificity, inhibition, and stability. Four double mutants, K45I/L90M, K45I/V82S, D30N/V82S, and N88D/L90M were selected for analysis on the basis of observations of increased or decreased stability or enzymatic activity for the respective single mutants. The double mutants were assayed for catalysis, inhibition, and stability. Crystal structures were analyzed for the double mutants at resolutions of 2.2–1.2 Å to determine the associated molecular changes. Sequence‐dependent changes in protease‐inhibitor interactions were observed in the crystal structures. Mutations D30N, K45I, and V82S showed altered interactions with inhibitor residues at P2/P2′, P3/P3′/P4/P4′, and P1/P1′, respectively. One of the conformations of Met90 in K45I/L90M has an unfavorably close contact with the carbonyl oxygen of Asp25, as observed previously in the L90M single mutant. The observed catalytic efficiency and inhibition for the double mutants depended on the specific substrate or inhibitor. In particular, large variation in cleavage of p6pol‐PR substrate was observed, which is likely to result in defects in the maturation of the protease from the Gag‐Pol precursor and hence viral replication. Three of the double mutants showed values for stability that were intermediate between the values observed for the respective single mutants. D30N/V82S mutant showed lower stability than either of the two individual mutations, which is possibly due to concerted changes in the central P2‐P2′ and S2‐S2′ sites. The complex effects of combining mutations are discussed. Proteins 2002;48:107–116. © 2002 Wiley‐Liss, Inc.
A distance‐dependent atomic knowledge‐based potential for improved protein structure selection
Authors: Lu Hui , Skolnick Jeffrey
Published: August 2002

A heavy atom distance‐dependent knowledge‐based pairwise potential has been developed. This statistical potential is first evaluated and optimized with the native structure z‐scores from gapless threading. The potential is then used to recognize the native and near‐native structures from both published decoy test sets, as well as decoys obtained from our group's protein structure prediction program. In the gapless threading test, there is an average z‐score improvement of 4 units in the optimized atomic potential over the residue‐based quasichemical potential. Examination of the z‐scores for individual pairwise distance shells indicates that the specificity for the native protein structure is greatest at pairwise distances of 3.5–6.5 Å, i.e., in the first solvation shell. On applying the current atomic potential to test sets obtained from the web, composed of native protein and decoy structures, the current generation of the potential performs better than residue‐based potentials as well as the other published atomic potentials in the task of selecting native and near‐native structures. This newly developed potential is also applied to structures of varying quality generated by our group's protein structure prediction program. The current atomic potential tends to pick lower RMSD structures than do residue‐based contact potentials. In particular, this atomic pairwise interaction potential has better selectivity especially for near‐native structures. As such, it can be used to select near‐native folds generated by structure prediction algorithms as well as for protein structure refinement. Proteins 2001;44:223–232. © 2001 Wiley‐Liss, Inc.
Mineralization of 2,4‐D, mecoprop, isoproturon and terbuthylazine in a chalk aquifer
Authors: Kristensen Gitte B , Sørensen Sebastian R , Aamand Jens
Published: August 2002

The potential to mineralize 2,4‐dichlorophenoxyacetic acid (2,4‐D), mecoprop, isoproturon and terbuthylazine was studied in soil and aquifer chalk sampled at an agricultural field near Aalborg, Denmark. Laboratory microcosms were incubated for 258 days under aerobic conditions at 10 °C with soil and chalk from 0.15–4.45 m below the surface. The [ring‐U‐14C]‐labeled herbicides were added to obtain a concentration of 6 µg kg−1and mineralization was measured as evolved [14C]carbon dioxide. The herbicides were readily mineralized in soil from the plough layer, except for terbuthylazine, which was mineralized only to a limited extent. In the chalk, lag periods of at least 40 days were observed, and a maximum of 51%, 33% and 6% of the added 2,4‐D, mecoprop and isoproturon, respectively, were recovered as [14C]carbon dioxide. Large variations in both rate and extent of mineralization were observed within replicates in chalk. No mineralization of terbuthylazine in chalk was observed. As a measure of the general metabolic activity towards aromatic compounds, [ring‐U‐14C]‐benzoic acid was included. It was readily mineralized at all depths.

© 2000 Society of Chemical Industry
Cytochromes P450 of insects: the tip of the iceberg
Authors: Scott Jeffrey G , Wen Zhimou
Published: August 2002

The cytochrome P450‐dependent monooxygenases are an extremely important metabolic system involved in the metabolism of endogenous compounds and xenobiotics. Collectively, P450 monooxygenases can metabolize numerous substrates and carry out multiple oxidative reactions. The large number of substrates metabolized is due to the plethora of P450 isoforms and to the broad substrate specificity of some isoforms. Monooxygenases of insects have several functional roles, including growth, development, feeding and protection against xenobiotics, including resistance to pesticides and tolerance to plant toxins. This review begins with background information about P450s and their evolution, followed by a discussion of the extraordinary diversity of insect P450s. Given the enormous interest in studying individual P450s, we then provide a synopsis of the different methods that have been used in their isolation and the substrates that are known to be metabolized. We conclude by summarizing the lessons we have learned from the study of individual insect P450s, including their roles in insecticide resistance, plant–insect interactions and insect physiology. However, these studies are just the ‘tip of the iceberg’. Our knowledge continues to expand at a rapid pace, suggesting that the next decade will outpace the last in terms of improving our understanding of the cytochromes P450 of insects.

© 2001 Society of Chemical Industry
Sex‐related differences in the tolerance of Oriental fruit moth (Grapholita molesta) to organophosphate insecticides
Authors: de Lame Frédérique M , Hong Jeon J , Shearer Peter W , Brattsten Lena B
Published: August 2002

In vivo toxicity assays have shown that organophosphate insecticides are less toxic to male than to female Oriental fruit moths Grapholita molesta. While male moths have higher levels of acetylcholinesterase and general esterase activities, female moth acetylcholinesterase enzymes are less sensitive to aromatic and aliphatic organophosphates than male enzymes. Elevated esterase and acetylcholinesterase activities in male moths explain their greater tolerance to aromatic and aliphatic organophosphates. Male and female acetylcholinesterase enzymes are equally tolerant to heteroaromatic organophosphates, the most widely used of this class of insecticides in G molesta control. This observation, in contrast to the greater sensitivity of male acetylcholinesterases to aromatic and aliphatic organophosphates, shows the potential for the evolution of insensitive target sites in male moths, which would increase male G molesta tolerance to these insecticides. Significant sex‐linked differences in insecticide tolerance have not been reported previously in lepidopterans. The practical implications of the observed differences in tolerance in male and female G molesta question the practice of using pheromone traps to monitor populations of these moths in orchards.

© 2001 Society of Chemical Industry
Assessment of leaching potential of aldicarb and its metabolites using laboratory studies
Authors: Fava Luca , Bottoni Paola , Crobe Angela , Caracciolo Anna Barra , Funari Enzo
Published: August 2002

The metabolites of pesticides can contaminate groundwater and pose a risk to human health when this water is used for drinking. This paper reports the results of a laboratory study on aldicarb and its main metabolites, aldicarb sulfone and aldicarb sulfoxide. Aldicarb and its metabolites showed Koc values (6–31) which were lower than that of atrazine (55), indicating that they are very mobile in soil. They are less persistent than atrazine (DT50 = 25 days), with DT50 values from less than 1 day and up to 12 days. Aldicarb behaved as a non‐leacher, whereas its metabolites clearly showed the characteristics of leachers. Aged residue leaching experiments showed that aldicarb can occur at high concentrations in the leachate, together with its two metabolites. The leachate composition depends on the incubation time of the parent compound. Aldicarb and its metabolites can form various mixtures in groundwater on the basis of the time elapsing between the application of the insecticide and the first significant rainfall. This study confirms the characteristics of contaminants of aldicarb and especially its metabolites, as reported in the literature.

© 2001 Society of Chemical Industry
Design of steel structures under fire conditions
Authors: Bennetts I D , Thomas I R
Published: August 2002

Changes have occurred internationally in regulations for fire safety in buildings, and there has been significant recent progress towards rational design for fire safety in buildings. Possible design objectives for fire safety are listed and the interacting factors that influence fire safety in buildings are discussed. A factor of particular importance is fire growth and development, with recent developments in this area leading to increased recognition of non‐uniform conditions occurring in many enclosures of practical significance in fire safety design. Coroner's records and fire statistics have been used to improve our understanding of the factors that lead to casualties (particularly fatalities) in fires, and these have shown that the structure is rarely a factor.

Recent progress in understanding and modelling the behaviour of steel structures in fires is reviewed. Recent testing for modern structural steels has resulted in new data for thermal expansion and stress‐related and creep strain, with new mathematical relationships for strain that can easily be used in computer models. Studies of the response of steel columns and composite beams are reviewed, including studies of the effect of temperature gradients and axial restraint on column performance, the development of a simplified equation for concrete‐filled tubular column behaviour and lateral buckling of beams. A major area of recent research is the behaviour in fire of significant parts of a building structure (rather than individual members), particularly in response to the Cardington eight storey steel‐framed building tests. Several recently published approaches to modelling overall structural behaviour are reviewed in the light of these tests.
Engineered durability for timber construction
Authors: Leicester R H
Published: August 2002

The application of reliable prediction models is essential for the development of performance‐based design procedures. Such models for the durability of timber construction are not available. A review of progress in the development of these models reveals that, while models do exist, they must be calibrated with the performance of real structures before they can be used for design. The development of models for predicting performance of constructions under attack by decay fungi, subterranean termites and corrosion is examined.
Acceptable risk bases for design of structures
Authors: Ellingwood Bruce R
Published: August 2002

Structural design standards provide the foundation of good engineering practice and a framework for addressing safety and serviceability issues rationally. Structural reliability methods provide the tools for managing uncertainties in modern codified structural design. Current probability‐based structural codes are based on performance measures expressed as notional reliabilities of structural components. These notional reliabilities, encapsulated in reliability indices, were obtained by calibrating the proposed codes to traditional practice rather than from quantitative risk analysis. Because the reliability estimates are based on models of real systems, they may not correspond to historical failure rates, and therefore confound the process of risk communication among structural engineers, building or regulatory officials, and the public. The research and professional engineering communities must work together to confront future challenges arising from new trends in structural engineering practice towards tailoring building design to performance expectations of the building owners, occupants and the public. In this context, the prospects of basing future codes on a quantitative acceptable risk measure warrant further examination.
Brine shrimp lethality assay of Bacopa monnieri
Authors: D'Souza Prashanth , Deepak Mundkinajeddu , Rani Padmaja , Kadamboor Sandhya , Mathew Anjana , Chandrashekar Arun P. , Agarwal Amit
Published: August 2002

Successive petroleum ether, chloroform, ethanol and water extracts, a saponin rich fraction (SRF) and bacoside A isolated from Bacopa monnieri were tested for brine shrimp lethality. Successive ethanol extracts and SRF showed potent activity. Bacoside A showed the maximum activity with a LC50 of 38.3 μg/mL. The results confirmed the previous reports of an anticancer effect of Bacopa monnieri and suggest bacoside A as the active constituent. Copyright © 2002 John Wiley & Sons, Ltd.
Kava and Valerian in the treatment of stress‐induced insomnia
Authors: Wheatley D.
Published: August 2002

Kava and valerian are herbal remedies, claimed to have anxiolytic and sedative properties respectively, without dependence potential or any appreciable side‐effects. In this pilot study, 24 patients suffering from stress‐induced insomnia were treated for 6 weeks with kava 120 mg daily. This was followed by 2 weeks off treatment and then, 5 having dropped out, 19 received valerian 600 mg daily for another 6 weeks. Stress was measured in three areas: social, personal and life‐events; insomnia in three areas also: time to fall asleep, hours slept and waking mood. Total stress severity was significantly relieved by both compounds (p < 0.01) with no significant differences between them; as was also insomnia (p < 0.01). The proportion of patients with no side‐effects was 58% with each drug respectively and the ‘commonest’ effect was vivid dreams with valerian (16%), followed by dizziness with kava (12% ). These compounds may be useful in the treatment of stress and insomnia but further studies are required to determine their relative roles for such indications. Copyright © 2001 John Wiley & Sons, Ltd.