bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of poly(L‐lactide)‐poly(ethylene glycol) multiblock copolymers
Authors: Luo Weijun , Li Suming , Bei Jianzhong , Wang Shenguo
Published: August 2002

Poly(L‐lactide)‐poly(ethylene glycol) multiblock copolymers with predetermined block lengths were synthesized by polycondensation of PLA diols and PEG diacids. The reaction was carried out under mild conditions, using dicyclohexylcarbodiimide as the coupling agent and dimethylaminopyridine as the catalyst. The resulting copolymers were characterized by various analytical techniques, such as GPC, viscometry, 1H‐NMR, FTIR, DSC, X‐ray diffractometry, and contact angle measurement. The results indicated that these copolymers presented outstanding properties pertinent to biomedical use, including better miscibility between the two components, low crystallinity, and hydrophilicity. Moreover, the properties of the copolymers can be modulated by adjusting the block length of the two components or the reaction conditions. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1729–1736, 2002; DOI 10.1002/app.10580
Soft segmental effect of methylene bis(p‐cyclohexyl isocyanate) based thermoplastic polyurethane impregnated with lithium perchlorate/propylene carbonate on ionic conductivity
Authors: Wen Ten‐Chin , Chen Hsuan‐Hsu
Published: August 2002

Thermoplastic polyurethane (TPU) was employed as the polymer matrix for ion conduction as gelled electrolytes with lithium perchlorate (LiClO4) in propylene carbonate (PC) solution. The TPU was prepared by methylene bis(p‐cyclohexyl isocyanate) as the hard segment while employing both poly(ethylene glycol) (PEG) and poly(tetramethylene glycol) (PTMG) as the soft segments. The copolymer comprising both PEG and PTMG was prepared such that it possessed the combined characteristics of good conductivity from the former and good mechanical properties from the latter. All the polymers were characterized by gel permeation chromatography, differential scanning calorimetry, and Fourier transform IR spectroscopy. The conductivity data were obtained from alternating current impedance experiments. The results revealed that the copolymer containing both PEG and PTMG as the soft segments showed better performance than TPU containing either PEG or PTMG. The copolymer TPU(PEG/PTMG) proved to be a good gelled electrolyte from 5 to 85°C. This copolymer, impregnated with 150% LiClO4/PC, possessed good mechanical strength and conductivity as high as 10−3 S/cm. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 935–942, 2001
Transesterification reaction kinetics of poly(ethylene terephthalate/poly(ethylene 2,6‐naphthalate) blends
Authors: Shi Yu , Jabarin Saleh A.
Published: August 2002

The transesterification reaction of poly(ethylene terephthalate)/poly(ethylene 2,6‐naphthalate) blends during melt‐mixing was studied as a function of blending temperature, blending time, blend composition, processing equipment, and different grades of poly(ethylene terephthalate) and poly(ethylene 2,6‐naphthalate). Results show that the major factors controlling the reaction are the temperature and time of blending. Efficiency of mixing also plays an important role in transesterification. The reaction kinetics can be modeled using a second‐order direct ester–ester interchange reaction. The rate constant (k) was found to have a minimum value at an intermediate PEN content and the activation energy of the rate constant was calculated to be 140 kJ/mol. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2422–2436, 2001
Effects of processing parameters on axial stiffness of self‐reinforced polyethylene composites
Authors: Amer Maher S. , Ganapathiraju Sunil
Published: August 2002

Self‐reinforced polyethylene composites have proven to be promising candidate materials for a number of wear‐resistance and bioimplant applications. In this study, we investigated the effects of processing parameters on the elastic modulus of self‐reinforced high‐density polyethylene (HDPE) composites. The processing parameters investigated were the cooling rate, processing pressure, temperature, and duration. Our results showed an optimum processing temperature, pressure, and duration that were matrix‐dependent. In addition, for an HDPE matrix, the slower the composite cooling rate was, the higher the composite modulus was. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1136–1141, 2001
Kinetic study of olefin polymerization with a supported metallocene catalyst. III. Ethylene homopolymerization in slurry
Authors: Chakravarti S. , Ray W. Harmon
Published: August 2002

A kinetic study of ethylene homopolymerization is conducted with a supported unbridged metallocene catalyst in a slurry reactor. The effects of operational parameters such as the reaction temperature and pressure on kinetics are investigated. The kinetic parameters which have been determined for this particular catalyst from previous gas phase studies are used in a slurry reactor model to predict the polymerization behavior under various reaction conditions. The experimental data compare favorably with the predictions from this model. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2901–2917, 2001
Mechanical relaxation processes of wood in the low‐temperature range
Authors: Obataya Eiichi , Norimoto Misato , Tomita Bunichiro
Published: August 2002

The dynamic viscoelastic properties of untreated and chemically modified wood specimens were determined in the temperature range 123 to 293 K and at constant frequencies. Absolutely dry wood specimens exhibited one relaxation process labeled γ at around 180 K, being attributed to the motions of methylol groups in the amorphous region of the wood constituents. The changes in the γ process due to the chemical modifications were explained by the reduction in the original γ loss peak due to the decrease of methylol groups, and an additional relaxation induced by the other groups introduced. With moisture adsorption, an additional relaxation labeled β was induced at 220–240 K. It appeared only when the wood adsorbed moisture irrespective of chemical modifications, and its characteristics were not affected by the formaldehyde and PEG treatments involving the remarkable changes in the mobility of amorphous molecules. These results suggested that the dominant mechanism of β relaxation was not the segmental motions of the main chain, but the motion of the adsorbed water molecules. The positive activation entropy of the β relaxation was interpreted to reflect rearrangement of the adsorption sites required for the rotation of the adsorbed water molecules. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3338–3347, 2001
Photopolymerizable liquid encapsulants for microelectronic devices: Thermal and mechanical properties of systems with reduced in‐mold cure times
Authors: Baikerikar Kiran K. , Scranton Alec B.
Published: August 2002

Photopolymerizable liquid encapsulants (PLEs) for microelectronic devices may offer important advantages over traditional transfer molding compounds, including reduced in‐mold cure times, lower thermal stresses, and reduced wire sweep. In this contribution, we discuss an encapsulation process based upon a low viscosity resin that cures rapidly upon exposure to UV light. These highly filled PLEs are comprised of an epoxy novolac‐based vinyl ester resin (∼25 wt %), fused silica filler (70–74 wt %), photoinitiator, silane coupling agent, and, in some cases, a thermal initiator. We have characterized the material properties (flexural strength and modulus, coefficient of thermal expansion, glass transition temperature, and thermal stress parameter) of PLEs cured with UV illumination times of 60, 90, and 120 s, as well as, the thermal conductivity and adhesive peel strength of PLEs photocured for 90 s. In addition, we investigated the effect of the fused silica loading and the initiation scheme on these properties. The results indicate that the PLEs are very promising for microelectronic encapsulation. These liquid encapsulants cure (to an ejectable hardness) in 1 min for an initiating light intensity of 200 mW/cm2, and exhibit appropriate values for the thermal and mechanical properties listed above. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3449–3461, 2001
Relationship between molecular structure and moisture‐retention ability of carboxymethyl chitin and chitosan
Authors: Chen Lingyun , Du Yumin , Wu Huiqing , Xiao Ling
Published: August 2002

Carboxymethyl chitins and chitosans (CM‐chitins, CM‐chitosans) of different substitution sites were prepared under different reaction conditions, and partially depolymerized carboxymethyl chitins of various molecular weights from 24.8 × 104 to 0.26 × 104 were obtained by degrading with chemical reagents. Degree of substitution (DS) was estimated by potentiometric titration. Substitution site was confirmed by infrared and 13C‐NMR spectra. Molecular weights were determined with gel permeation chromatography and gel permeation chromatography combined with laser light scattering (GPC‐LLS). Moisture‐absorption and retention abilities of these compounds were tested in comparison with those of hyaluronic acid (HA). The results reveal that 6‐carboxymethyl group in the molecular structure of chitin and chitosan is a main active site responsible for moisture retention. Although carboxymethylation at OH‐3 and N position is not essential, they contribute to the ability. Moisture‐retention ability is also related to molecular weight; that is, higher molecular weight helps to improve moisture‐retention ability. 6‐O‐CM‐chitin (chitosan) with a DS above 0.8 and molecular weight higher than 24.8 × 104 has the potential to substitute for HA for use in cosmetics and clinical medicine. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1233–1241, 2002
Experimental provision of large woody debris in streams as a trout management technique
Authors: Lehane B.M. , Giller P.S. , O'Halloran J. , Smith C. , Murphy J.
Published: August 2002

The natural stock of large woody debris (LWD) in the afforested Douglas River (Fermoy, Co. Cork) is very low relative to old‐growth forests, which seems to arise from deficiency both of supply and retention. Woody debris is important to the ecology and physical structure of forest streams, so its abundance is relevant to aquatic conservation and the maintenance and size of salmonid fish stocks.

The physical characteristics and fish stocks of 16 contiguous segments of two 200 m stream reaches were surveyed in spring 1998 prior to the installation of 12 partially spanning debris structures on four of the segments. This study investigated the effect of debris structures on the heterogeneity of flow and substratum, and the distribution of brown trout (Salmo trutta), and assessed the potential use of woody debris manipulation as a tool in the management of forest streams.

Surveys of stream habitat conditions over a 2 year period following the installation of woody debris showed a change in stream architecture. This created more suitable habitat for trout through development of additional pools in which beds of fine sediment developed, and constraining the main current, increasing the amount of eddies and slack water areas.

There were significant increases in trout density and biomass in the debris segments relative to control segments without debris dams 1 and 2 years after debris addition, although trout condition was not modified by the addition of LWD. These results suggest that the addition of woody debris offers a positive and practical management technique for enhancing fish in plantation forest streams.

Copyright © 2002 John Wiley & Sons, Ltd.
Value of laboratory tests in early prediction of rheumatoid arthritis
Authors: Saraux Alaian , Berthelot Jean M. , Gérard Chalès  , Le Henaff Catherine , Mary Jean Y. , Thorel Jean B. , Hoang Sylvie , Dueymes Maryvonne , Allain Jérôme , Devauchelle Valerie , Baron Dominique , Le Goff Paul , Youinou Pierre
Published: August 2002

Objective

To determine which laboratory test or tests at presentation best predicted a diagnosis of rheumatoid arthritis (RA) 2 years later.

Methods

Two hundred seventy patients with early arthritis seen in 7 hospitals underwent comprehensive evaluations at 6‐month intervals for 2 years, when the diagnosis of RA was assessed by 5 rheumatologists. The sensitivity and specificity of each test at the first visit for discriminating between RA (38%, n = 98) and non–RA patients were determined. Optimal cutoffs for continuous tests were derived from receiver operating characteristic curves. Sensitivity and specificity of test combinations selected by multiple logistic regression were determined.

Results

IgM rheumatoid factor (RF) by enzyme‐linked immunosorbent assay, IgG‐antikeratin antibody (AKA), and latex test had the strongest associations with RA. These 3 tests formed the most powerful combination for distinguishing RA from non–RA.

Conclusion

IgM‐RF, IgG‐AKA, and the latex test are the best laboratory tests for discriminating between patients with and without RA. Combining these tests slightly improves diagnostic value.
RNA commutes to work: regulation of plant gene expression by systemically transported RNA molecules
Authors: Ueki Shoko , Citovsky Vitaly
Published: August 2002

Although long‐distance movement of endogenous mRNAs in plants is well established, the functional contributions of these transported RNA molecules has remained unclear. In a recent report, Kim et al.2001 showed that systemically transported mRNA is capable of causing phenotypic change in developing tissue. Here, this finding and its significance are reviewed and discussed in detail. In addition, in order to give proper perspective, long‐distance transport of other types of RNAs, e.g., RNA elicitors of post‐transcriptional gene silencing and RNA genomes of plant viruses, and its possible regulation are discussed. BioEssays 23:1087–1090, 2001. © 2001 John Wiley & Sons, Inc.
Enteric glial cells. An upstream target for induction of necrotizing enterocolitis and Crohn's disease?
Authors: Bush Toby G.
Published: August 2002

As a direct consequence of the sophisticated arrangement of its intrinsic neurons, the gastrointestinal tract is unique among peripheral organs, in its ability to mediate its own reflexes. Neurons of the enteric nervous system are intimately associated with enteric glial cells. These supporting cells do not resemble Schwann cells, the glial cell found in all other parts of the peripheral nervous system, but share many similarities with astrocytes of the central nervous system. Ablation of enteric glial cells in adult transgenic mice has demonstrated that these cells are essential to maintain the integrity of the small intestine. Acute loss of enteric glial cells induces massive pathological changes with similarities to necrotizing enterocolitis (NEC) and early Crohn's disease. These human conditions share some mechanistic similarities. Identification of enteric glial cell dysfunction/loss as sufficient to induce necrotic/inflammatory bowel disease may be important to understand the pathogenesis of both NEC and Crohn's disease. BioEssays 24:130–140, 2002. © 2002 Wiley Periodicals, Inc.
Tetrazole analogues of cyclolinopeptide A: Synthesis, conformation, and biology
Authors: Kaczmarek Krzysztof , Jankowski Stefan , Siemion Ignacy Z. , Wieczorek Zbigniew , Benedetti Ettore , Di Lello Paola , Isernia Carla , Saviano Michele , Zabrocki Janusz
Published: August 2002

Linear and cyclic analogues of cyclolinopeptide A (CLA) with two dipeptide segments (Val5Pro6 and Pro6Pro7) replaced by their tetrazole derivatives were synthesized by the SPPS technique and cyclized using TBTU (O‐(benzotriazol‐1‐yl)‐1,1,3,3‐tetramethyluronium tetrafluoroborate) reagent. The conformational properties of the c(Leu1Ile2Ile3Leu4Val5Pro6 ψ[CN4]Ala7Phe8Phe9) were investigated by NMR and computational techniques. The overall solution structure of this cyclic peptide resembles that observed for the CLA in the solid state. These studies of cyclic tetrazole CLA analogue confirm that the 1,5‐disubstituted tetrazole ring functions as an effective, well‐tolerated cis‐amide bond mimic in solution. The peptides were examined for their immunosuppressive activity in the humoral response test. For cyclic analogues the immunosuppressive activity, at low doses, is equal in magnitude to the activity presented by cyclosporin A and native CLA. The conformational and biological data seem indicate that the ProProPhePhe moiety and the preservation of the CLA backbone conformation are important for immunosuppressive activity. © 2002 Wiley Periodicals, Inc. Biopolymers 63: 343–357, 2002
Kinetic multichannel spectroscopy of biological molecules: Decomposition of the spectral matrix
Authors: Zimányi László
Published: August 2002

The time‐resolved difference spectra after flash excitation of various biological molecules are measured on a gated optical multichannel analyzer. Electron transfer between the photoactive covalent label thiouredopyrene‐trisulfonate and the heme of cytochrome c and the photocycle of the E204Q mutant bacteriorhodopsin are studied. The spectral matrices containing consecutive difference spectra are analyzed to reveal the reaction kinetics and individual component spectra. Singular value decomposition combined with stoichiometric analysis and self‐modeling is demonstrated as a tool for successful dissection of the matrix, despite the difficulties arising from broad, featureless, overlapping spectra and the overlapping kinetics of the components. © 2002 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 67: 263–266, 2002
Unusual swelling of elastin
Authors: Lillie M. A. , Gosline J. M.
Published: August 2002

The swelling behavior of the elastin network has been investigated by comparing the linear expansion of samples of purified elastin with the volume expansion of the network, calculated on the basis of composition. Elastin sample dimensions and sample masses were measured under three conditions in which volume changes: thermal expansion at fixed water contents, deswelling due to dehydration, and swelling to greater than normal levels due to the swelling agent, sodium dodecyl sulfate. Isotropic network swelling usually changes length in proportion to the cube root of network volume, but length was found to be directly proportional to volume, showing a greater increase in length than expected. This unusual swelling behavior is attributed to an unusual elastin structure at the subfiber level, but there is insufficient detail on elastin's molecular organization to identify a mechanism to explain how it occurs. Assuming the network swells homogeneously, we describe two models that correctly predict swelling behavior, but these models imply a significant deviation from the structure generally assumed for an elastomeric polymer network of kinetically free molecular chains. Assuming that the network swells heterogeneously removes part of the difficulty with the models, but the observed direct proportionality between length and network volume remains to be explained. © 2002 Wiley Periodicals, Inc. Biopolymers 64: 115–126, 2002
Development of a process model to describe the synthesis of (R)‐mandelonitrile by Prunus amygdalus hydroxynitrile lyase in an aqueous–organic biphasic reactor
Authors: Willeman Wouter F. , Gerrits Pieter Jan , Hanefeld Ulf , Brussee Johannes , Straathof Adrie J. J. , van der Gen Arne , Heijnen Joseph J.
Published: August 2002

A process model for the enzymatic synthesis of (R)‐cyanohydrins in an aqueous–organic biphasic‐stirred tank reactor was developed. The conversion of benzal‐dehyde into (R)‐mandelonitrile, catalyzed by Prunus amygdalus hydroxynitrile lyase at 5°C and pH 5.5, was chosen as a model system with methyl tert‐butyl ether as the organic phase. The process model consisted of a description of the reaction kinetics, mass transfer kinetics, and the mass balances for both the aqueous and the organic phase. Values for the enzyme kinetic parameters, according to ordered bi‐uni kinetics, the lumped mass transfer coefficient for benzaldehyde, and the partition coefficients were determined separately. The process model is validated by using 11 experimental data sets of batch conversions in the aqueous–organic biphasic‐stirred tank reactor. In these 11 experiments, different enzyme concentrations and phase volume ratios were used. The model was found to be valid with respect to both the conversion and the enantiomeric excess. To synthesize cyanohydrins with a high enantiomeric excess, the enzyme is required to work at mass transfer limited conditions. The developed process model will be used to investigate other process concepts and other substrates. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 239–247, 2002.
Production of chiral R‐3‐hydroxyalkanoic acids and R‐3‐hydroxyalkanoic acid methylesters via hydrolytic degradation of polyhydroxyalkanoate synthesized by pseudomonads
Authors: de Roo Guy , Kellerhals Michele B. , Ren Qun , Witholt Bernard , Kessler Birgit
Published: August 2002

A novel and efficient method for the production of enantiomericaly pure R‐3‐hydroxyalkanoic acids and R‐3‐hydroxyalkanoic acid methylesters was developed. The described method is based on hydrolysis of poly(hydroxyalkanoate) copolymers synthesized by Pseudomonas putida. The polymer was isolated via solvent recovery and hydrolyzed by acid methanolysis. The obtained 3‐hydroxyalkanoic acid methylester mixture was distilled into several fractions with an overall yield of 96.6% (w/w). Gas chromatography–mass spectrometry analysis of the fractions showed that 3‐hydroxyhexanoic‐, 3‐hydroxyoctanoic‐, 3 hydroxydecanoic‐, and 3‐hydroxydodecanoic acid methylesters were enriched to purities exceeding 96 mol%, with distillation yields of 99.9, 99.8, 88.4, and 56.8% (w/w), respectively. Subsequent saponification of the purified methylester fractions yielded the corresponding 3‐hydroxyalkanoic acids, which were recovered up to 92.8% (w/w). Chiral gas chromatography analysis confirmed that both 3‐hydroxyoctanoic acid and 3‐hydroxyoctanoic acid methylester are present in the R‐form at a very high enantiomeric excess (>99.9%). © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 717–722, 2002.
Formation of metabolites during biodegradation of linear alkylbenzene sulfonate in an upflow anaerobic sludge bed reactor under thermophilic conditions
Authors: Mogensen A. S. , Ahring B. K.
Published: August 2002

Biodegradation of linear alkylbenzene sulfonate (LAS) was shown in an upflow anaerobic sludge blanket reactor under thermophilic conditions. The reactor was inoculated with granular biomass and fed with a synthetic medium and 3 μmol/L of a mixture of LAS with alkylchain length of 10 to 13 carbon atoms. The reactor was operated with a hydraulic retention time of 12 h with effluent recirculation in an effluent to influent ratio of 5 to 1. A sterile reactor operated in parallel revealed that sorption to sludge particles initially accounted for a major LAS removal. After 8 days of reactor operation, the removal of LAS in the reactor inoculated with active granular biomass exceeded the removal in the sterile reactor inoculated with sterile granular biomass. The effect of sorption ceased after 185 to 555 h depending on the LAS homologs. 40% of the LAS was biodegraded, and the removal rate was 0.5 × 10−6mol/h/mL granular biomass. Acidified effluent from the reactor was subjected to dichloromethane extraction followed by gas chromatography/mass spectrometry. Benzenesulfonic acid and benzaldehyde were detected in the reactor effluent from the reactor with active granular biomass but not in the sterile and unamended reactor effluent. Benzenesulfonic acid and benzaldehyde are the first identified degradation products in the anaerobic degradation of LAS. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 483–488, 2002; DOI 10.1002/bit.10195
Changing economies of scale – synergies between implementation of an ecological tax reform and development of industrial ecosystems
Authors: Bey Christoph
Published: August 2002

In this paper an investigation is presented into the long‐term effects of an ecological tax reform. Exploring time frames of different length, the paper considers the reform's effects on manufacturing systems, especially on economies of scale. Industrial ecology, a framework for restructuring into industrial ecosystems, is one attempt at transforming the socio‐economic system for sustainability. The paper points out the synergetic effects an ecological tax reform has with those restructuring efforts for sustainable industry and society. For that purpose, the economies of scale in the current linear production system and those found in the closed‐loop circular structures of industrial ecosystems are compared, and the paper is concluded by a discussion of opportunity costs of implementation of an ecological tax reform and industrial ecological restructuring. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
Circular dichroism and absorption studies of (‐)‐2,2′‐dimethyl‐4,5‐(1‐naphthyl)‐1,3‐dioxolane in terms of vibronic coupling theory
Authors: Makowski Marcin , Pilch Mariusz , Pawlikowski Marek T.
Published: August 2002

The absorption and circular dichroism (CD) spectra of (‐)‐2,2′‐dimethyl‐4,5‐(1‐naphthyl)‐1,3‐dioxolane (DND) were studied in the energy region 30,000 cm−1 to 50,000 cm−1. The DND ketal is treated as a naphthalene dimer and its spectra are interpreted in terms of a vibronic dimer model which includes the 1La and 1Bb states of the naphthalene chromophore. To fix the most stable conformation of DND molecule, the MNDO/AM1, RHF/6‐31G, and SVWN5, BPW91 methods are employed with 6‐31G and 6‐31G(d',p') basis sets. All the methods are shown to yield the DND geometry that is entirely consistent with the CD and absorption spectra studied. Chirality 14:274–283, 2002. © 2002 Wiley‐Liss, Inc.
Effective enzymatic resolution of rac‐1‐(3‐trifluoromethylphenyl)propan‐2‐ol, precursor of fenfluramine
Authors: D'Antona Nicola , Mangiafico Sebastiano , Nicolosi Giovanni
Published: August 2002

Lipases from Candida antarctica and from Mucor miehei efficiently catalyze the enantioselective esterification of rac‐1‐(3‐trifluoromethylphenyl)propan‐2‐ol. The obtained enantioforms are suitable to prepare both enantiomers of fenfluramine. Chirality 14:325–328, 2002. © 2002 Wiley‐Liss, Inc.
Loss of heterozygosity on chromosome arms 3p and 6q in microdissected adenocarcinomas of the uterine cervix and adenocarcinoma in situ
Authors: Acevedo Claudia M. , Henríquez Marcela , Emmert‐Buck Michael R. , Chuaqui Rodrigo F.
Published: August 2002

BACKGROUND

Despite the increasing frequency of adenocarcinomas of the uterine cervix, little is known regarding inactivation of tumor suppressor genes (TSGs) in this tumor type. The authors analyzed loss of heterozygosity (LOH) in 36 carcinomas of the cervix with glandular differentiation, and 5 adenocarcinoma in situ in 40 patients.

METHODS

The authors analyzed samples using laser capture microdissection from archival material and DNA amplified with microsatellite markers on the following loci: 3p14.2 (D3S1234, D3S1300), 3p21.3 (D3S1029, D3S1447), 3p22‐24 (D3S1537, D3S1351), 6q21‐23.3 (D6S250), 6q25.1 (ESR), 6q25.2 (D6S255), 8p21 (D8S136, D8S1820), 13q12.3 (D13S220, D13S267), 17q21 (D17S579, D17S855). Eight additional markers spanning the short arm of chromosome 3 (3p12‐p25) and six spanning the long arm of chromosome 6 (6q11‐q27) were studied in the cases showing LOH to further define the deletion intervals.

RESULTS

The frequency of allelic loss in cancers was chromosome 3p: 49% (p14.2: 35%, p21.3: 23%, p22‐24: 41%), 6q: 48% (q21‐23.1: 39%, q25.1: 45%, q25.2: 7%), 13q: 22%, 17q: 6%, and 8p: 18%. On chromosome arm 3p, the authors' data suggest at least two discrete areas of deletion: a proximal area between markers D3S1234 (p12) and D3S1766 (p14.2‐14.3), and a second distal interval, telomeric from marker D3S4623 (p21.3). On chromosome 6q, the deletion area is between marker D6S300 (q22) and D6S255 (q25.2). Two of five preneoplastic lesions showed LOH on chromosome arm 3p, and two five showed allelic loss on chromosome arm on 6q, suggesting the genes might be inactivated early in cervical tumorigenesis.

CONCLUSIONS

The authors have identified three chromosomal regions that may harbor TSGs involved in the development/progression of adenocarcinomas of the uterine cervix, 3p12‐14.2, 3p21.3‐pter, and 6q22‐25.2. Deletions also were detected in adenocarcinoma in situ, suggesting the genes may be inactivated early in cervical tumorigenesis. Cancer 2002;94:793–802. © 2002 American Cancer Society.

DOI 10.1002/cncr.10275
Helicobacter pylori infection in patients with gastric involvement by adult T‐cell leukemia/lymphoma
Authors: Ohnita Ken , Isomoto Hajime , Mizuta Yohei , Maeda Takahiro , Haraguchi Masuho , Miyazaki Masanobu , Murase Kunihiko , Murata Ikuo , Tomonaga Masao , Kohno Shigeru
Published: August 2002

BACKGROUND

Gastrointestinal involvement is seen frequently in patients with adult T‐cell leukemia/lymphoma (ATLL). The authors previously showed a relatively low prevalence of Helicobacter pylori infection in individuals with human T‐cell lymphotropic virus 1 (HTLV‐1) infection, including patients with ATLL; however, the correlation between H. pylori infection and ATLL gastric involvement has not been investigated.

METHODS

The authors studied 71 patients with ATLL. Gastric involvement was confirmed by endoscopy and biopsy. H. pylori infection was detected by serology, rapid urease test, and immunohistochemistry on biopsy samples. The expression of adhesion molecules on ATLL cells or their ligands on the vasculature in gastric mucosa was analyzed immunohistochemically. The expression of mucosal addressin cell adhesion molecule 1 (MAdCAM‐1) was detected by reverse transcriptase‐polymerase chain reaction (RT‐PCR) analysis.

RESULTS

Gastric involvement was detected in 21 patients (30%), including 8 patients with acute clinical subtype ATLL and 13 patients with lymphoma type ATLL. The prevalence of H. pylori infection was 86% (18 of 21 patients) in the patients with gastric involvement but only 38% (19 of 50 patients) in the patients without such involvement (P < 0.001). The expression of lymphocyte function‐associated antigen 1 (LFA‐1) and its ligand, intercellular adhesion molecule 1 (ICAM‐1), was most frequent on ATLL cells infiltrating the stomach and was enhanced substantially on vascular endothelium in H. pylori‐infected gastric mucosa. Human mucosal lymphocyte antigen 1 also was expressed on infiltrating ATLL cells in the stomach. The expression of MAdCAM‐1 mRNA assessed by RT‐PCR also was seen selectively in H. pylori‐infected patients.

CONCLUSIONS

ATLL cells infiltrate gastric tissues infected with H. pylori, probably through the interaction of adhesion molecules on these cells and their ligands on the vasculature, i.e., through the LFA‐1/ICAM‐1 pathway. Cancer 2002;94:1507–16. © 2002 American Cancer Society.

DOI 10.1002/cncr.10367
Postmenopausal cancer risk after self‐reported endometriosis diagnosis in the Iowa Women's Health Study
Authors: Olson Janet E. , Cerhan James R. , Janney M.S. Carol A. , Anderson Kristin E. , Vachon Celine M. , Sellers Thomas A.
Published: August 2002

BACKGROUND

Endometriosis, the presence of endometrial tissue outside the uterus, has an estimated prevalence between 4% and 10%. A recent study reported that women with a hospital discharge diagnosis of endometriosis were at increased risk of cancer at any site, breast cancer, ovarian cancer, and hematopoietic malignancies, especially non‐Hodgkin lymphoma (NHL).

METHODS

The authors examined whether self‐reported diagnosis of endometriosis was associated with increased risk of various cancers in the Iowa Women's Health Study. Incident cancer cases were identified from 1986 through 1998. Cox proportional hazards regression models were used to calculate relative risks and 95% confidence intervals for the particular cancers of interest.

RESULTS

Of 37,434 participants in this analysis, 3.8% reported a history of endometriosis at baseline in 1986. After 13 years of follow‐up, 1795 breast, 188 ovarian, and 243 NHL cases were detected in the cohort. Endometriosis was not associated with risk of all cancers combined (age‐adjusted relative risk [RR], 0.9; 95% confidence interval [CI], 0.7–1.2), breast carcinoma (RR, 1.0; 95% CI, 0.8–1.3), or ovarian carcinoma (RR, 0.8; 95% CI, 0.2–2.4). However, endometriosis was significantly associated with risk of NHL (age‐adjusted RR, 1.8; 95% CI, 1.0–3.0), especially diffuse NHL (RR, 3.2; 95% CI, 1.8–5.6). Multivariate adjustment had minimal effect on the point estimates of risk (NHL RR, 1.7; 95% CI, 0.97–2.7; diffuse NHL RR, 3.3; 95% CI, 1.9–5.9). Endometriosis was not associated with elevated risk of lung, urinary tract, endometrial, melanoma, or colorectal carcinomas (RRs, 1.2, 0.8, 1.2, 0.7, and 0.7, respectively).

CONCLUSIONS

These results corroborate a previously reported association between endometriosis and increased risk of NHL but not cancer at other sites. Cancer 2002;94:1612–18. © 2002 American Cancer Society.

DOI 10.1002/cncr.10370
A Phase II study of paclitaxel by 24‐hour infusion and ifosfamide in anthracycline‐resistant metastatic breast carcinoma
Authors: Seo Jae H. , Whang Young M. , Kim Byung S. , Choi Chul W. , Shin Sang W. , Kim Yeul H. , Kim Jun S. , Goo Bum H.
Published: August 2002

BACKGROUND

A Phase II study was performed to investigate the efficacy and tolerability of paclitaxel and ifosfamide chemotherapy for the treatment of anthracycline‐resistant metastatic breast carcinoma (MBC).

METHODS

Recurrent or progressed MBC within 12 months after anthracycline‐based chemotherapy was defined as anthracycline‐resistant. A 24‐hour infusion of paclitaxel (175 mg/m2) on Day 1 and subsequent infusions of ifosfamide (1.8 g/m2/day) with mesna (360 mg/m2/day) on Days 2– 4, were performed every 3 weeks. Twenty‐one patients were eligible for toxicity analysis. Response rate and survival duration were evaluated in 21 patients. Frontline chemotherapy was the FAC (5‐fluorouracil, doxorubicin, cyclophosphamide) regimen in all patients.

RESULTS

Objective response was found in 9 patients (42.9%), including complete response in 3 (13.4%). Median response duration and median survival duration were 10 months (range, 2–24+) and 19+ months (range, 2–32+), respectively. Sixteen (76%) experienced Grade 3/4 leukopenia controllable with granulocyte macrophage colony‐stimulating factor. Other significant toxicities were peripheral neuropathy (n = 3), mucositis (n = 2), and liver dysfunction (n = 1). However, there was no chemotherapy‐related death.

CONCLUSIONS

Paclitaxel by 24‐hour infusion combined with ifosfamide is efficacious in the treatment of anthracycline‐resistant MBC with tolerable toxicity. Further trials verifying the result of the authors' study are warranted. Cancer 2002;94:1925–30. © 2002 American Cancer Society.

DOI 10.1002/cncr.10431
The dynamics of prostate specific antigen during watchful waiting of prostate carcinoma
Authors: Vollmer Robin T. , Egawa Shin , Kuwao Sadahito , Baba Shiro
Published: August 2002

BACKGROUND

For the moment, there is uncertainty about the usefulness of early treatment of localized prostate carcinoma, uncertainty about whether some patients with early cancer can be managed expectantly, and uncertainty about how such patients might be recognized.

METHODS

The authors studied serial values of prostate specific antigen (PSA) in 94 Japanese men with diagnosed prostate carcinoma and who were managed by watchful waiting. Their median follow‐up duration was 32 months (range, 1.6–118). The authors used a log‐linear model to fit the values of PSA over time, and then they used the Cox survival model to relate the intercept (PSA amplitude) and slope (relative velocity) to observed local or systemic outcomes that were independent of PSA.

RESULTS

The authors found that the log‐linear model fit the serial values of PSA during watchful waiting very well. Prostate specific antigen amplitude related significantly to T classification (P = 0.0006), but not to grade (P > 0.2), and the relative velocity related significantly to both T classification (P = 0.009) and to grade (P = 0.02). Although the T classification, histologic grade, and log(PSA) at diagnosis were associated significantly with time to outcome, the combination of amplitude and relative velocity provided more information. These 2 PSA parameters resulted in a higher model likelihood ratio, and their individual P values in the Cox model were 0.0005 and 0.005, respectively. With these two in the Cox model, T classification, grade, log(PSA), and PSA doubling time provided no further significant information.

CONCLUSIONS

A log‐linear model seems to fit serial measurements of PSA during watchful waiting, and preliminary results suggest that both the amplitude and the relative velocity relate closely to clinical outcomes. Cancer 2002;94:1692–8. © 2002 American Cancer Society.

DOI 10.1002/cncr.10443
Topoisomerase IIα gene expression is regulated by the p53 tumor suppressor gene in nonsmall cell lung carcinoma patients
Authors: Liu Dage , Huang Cheng‐long , Kameyama Kotaro , Hayashi Eiichi , Yamauchi Akira , Sumitomo Shinichi , Yokomise Hiroyasu
Published: August 2002

BACKGROUND

Topoisomerase IIα (Topo IIα) is an essential nuclear enzyme for chromosome segregation during mitosis. Previous experimental studies using cell lines reported that Topo IIα expression was negatively regulated by wild‐type p53 through the gene's promoter region.

METHODS

Surgically resected tumor specimens from 98 nonsmall cell lung carcinoma (NSCLC) patients who were not treated with preoperative chemotherapy were studied. Quantitative reverse‐transcription polymerase chain reaction analysis was done to evaluate Topo IIα gene expression. Polymerase chain reaction single strand conformation polymorphism following sequencing was performed to investigate mutations of p53.

RESULTS

Topo IIα gene expression in squamous cell carcinomas was significantly higher than in adenocarcinomas (P = 0.0007). Topo IIα gene expression in moderately differentiated tumors and poorly differentiated tumors was significantly higher than in well differentiated tumors (P = 0.0032 and P = 0.0005, respectively). Thirty nine tumors (40%) had mutations of p53. Topo IIα gene expression in tumors with mutant p53 was significantly higher than in those with wild‐type p53 (P = 0.0224).

CONCLUSIONS

The current study suggests that Topo IIα gene expression is regulated by p53 gene status in NSCLC patients and that the overexpression of Topo IIα induced by mutant p53 might cause more aggressive carcinogenesis. Cancer 2002;94:2239–47. © 2002 American Cancer Society.

DOI 10.1002/cncr.10450
Prognostic value of cyclin B1 in patients with esophageal squamous cell carcinoma
Authors: Takeno Shinsuke , Noguchi Tsuyoshi , Kikuchi Ryuichi , Uchida Yuzo , Yokoyama Shigeo , Müller Wolfram
Published: August 2002

BACKGROUND

It has been reported that p53 regulates the G2‐M checkpoint transition through cyclin B1, and it has been suggested that p53 plays an important role in the development and progression of various malignancies. The objective of the current study was to clarify the role of the cell cycle regulators, cyclin B1 and p53, in patients with esophageal squamous cell carcinoma (ESCC).

METHODS

Tissue samples from 71 patients with ESCC were included in the current study. Expression levels of cyclin B1 and p53 in samples of normal squamous epithelium, dysplasia, and tumor cells from patients with ESCC were analyzed by immunohistochemistry.

RESULTS

Several cells in the basement layer of normal epithelium expressed cyclin B1. The number of cyclin B1 positive cells tended to increase as the degree of dysplasia increased from low grade to high grade. More than 20% of tumor cells were cyclin B1 positive in 38 patients (49.3%). Several clinicopathologic parameters, including macroscopic configuration (P < 0.01), pathologic tumor status (P < 0.05), pathologic lymph node status (P < 0.001), pathologic metastatic status (P < 0.01), tumor stage (P < 0.0001), and invasion of lymphatic vessels (P < 0.05), were correlated with the overexpression of cyclin B1. Elevated expression levels of cyclin B1 also were correlated with a poor prognosis in patients with ESCC in univariate analysis (P < 0.0001) and multivariate analysis (P = 0.0135). In contrast, p53 expression exhibited no significant correlation with the level of cyclin B1 expression and was not associated with prognostic parameters in patients with ESCC.

CONCLUSIONS

These findings suggest that cyclin B1 is involved in the pathogenesis of carcinoma of the esophagus and that elevated levels of cyclin B1 expression, but not p53 expression, may indicate a poor prognosis for patients with ESCC. Cancer 2002;94:2874–81. © 2002 American Cancer Society.

DOI 10.1002/cncr.10542
Hypophysiotropic neurons of the paraventricular nucleus respond in spatially, temporally, and phenotypically differentiated manners to acute vs. repeated restraint stress: Rapid publication
Authors: Viau Victor , Sawchenko Paul E.
Published: August 2002

Hypothalamic‐pituitary‐adrenal (HPA) responses to stress are initiated by parvicellular neurosecretory neurons in the medial parvicellular (mp) part of the paraventricular hypothalamic nucleus (PVH), which express corticotropin‐releasing factor (CRF), among other neuropeptides. We have used an approach guided by patterns of stress‐induced Fos expression to explore the manner in which anatomically and phenotypically defined components of the mpPVH respond to acute vs. repeated restraint stress. Hormonal indices of HPA activation in animals exposed to the last of 14 daily repeated restraint sessions were significantly lower than those in rats receiving a single restraint episode. Although this habituation was paralleled by global decrements in activation patterns across all PVH compartments, clear spatial‐temporal differences in recruitment profiles were noted between dorsal and ventral aspects of the mpPVH. Thus, acute restraint provoked a biphasic Fos induction, which occurred first within the mpPVH and in an adjoining population of somatostatinergic cells in the periventricular region and only later within other aspects of the PVH. By contrast, Fos responses of habituated animals were monophasic and focused decisively within a discrete ventral aspect of the mpPVH. The ventral population was identified as comprising neurons that express CRF and/or enkephalin and, to a lesser extent, growth hormone‐releasing factor. These results indicate a lack of homogeneity among stress‐responsive parvicellular neurosecretory neurons and suggest that distinct complements of CRF cells may be preferentially involved in initiating HPA responses to acute stress and sustaining them in the repeated condition. J. Comp. Neurol. 445:293–307, 2002. © 2002 Wiley‐Liss, Inc.
Parkin immunoreactivity in the brain of human and non‐human primates: An immunohistochemical analysis in normal conditions and in Parkinsonian syndromes
Authors: Zarate‐Lagunes Martin , Gu Wen‐Jie , Blanchard Véronique , Francois Chantal , Muriel Marie‐Paule , Mouatt‐Prigent Annick , Bonici Bruno , Parent André , Hartmann Andreas , Yelnik Jérôme , Boehme Georg A. , Pradier Laurent , Moussaoui Saliha , Faucheux Baptiste , Raisman‐Vozari Rita , Agid Yves , Brice Alexis , Hirsch Etienne C.
Published: August 2002

The etiology of Parkinson's disease is unknown, but the gene involved in an autosomic recessive form of the disease with early onset has recently been identified. It codes for a protein with an unknown function called parkin. In the present study we produced a specific polyclonal antiserum against human parkin. Immunohistochemical analysis showed that parkin is expressed in neuronal perikarya and processes but also in glial and blood vessels in the primate brain (human and monkey). Electron microscopy indicated that parkin immunoreactivity is mostly located in large cytoplasmic vesicles and at the level of the endoplasmic reticulum. Parkin was expressed heterogeneously in various structures of the brain. It was detectable in the dopaminergic systems at the level of the perikarya in the mesencephalon but also in the striatum. However, parkin was also expressed by numerous nondopaminergic neurons. The staining intensity of parkin was particularly high in the hippocampal formation, the pallidal complex, the red nucleus, and the cerebellum. Comparison of control subjects with patients with Parkinson's disease and control animals with 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐intoxicated animals revealed a loss of parkin‐immunoreactive neurons only in the substantia nigra pars compacta. Furthermore, the surviving dopaminergic neurons in the parkinsonian state continued to express parkin at a level similar to that observed in the control situation. These data indicate that parkin is a widely expressed protein. Thus, the degeneration of dopaminergic neurons in familial cases of Parkinson's disease with autosomal recessive transmission cannot be explained solely in terms of an alteration of this protein. J. Comp. Neurol. 432:184–196, 2001. © 2001 Wiley‐Liss, Inc.
Topographic organization of suprachiasmatic nucleus projection neurons
Authors: Leak Rehana K. , Moore Robert Y.
Published: August 2002

The mammalian circadian pacemaker, the hypothalamic suprachiasmatic nucleus (SCN), has two subdivisions. The core is located above the optic chiasm, receives primary and secondary visual afferents, and contains neurons producing vasoactive intestinal polypeptide and gastrin‐releasing peptide. The shell largely surrounds the core, receives input from nonvisual sources and contains neurons producing arginine vasopressin and calretinin. In this study, we tested the hypothesis that SCN efferent projections are topographically organized with respect to the subdivision of origin. Injections of retrograde tracers were placed in major sites of efferent termination, described from prior studies that used anterograde tracers (Watts and Swanson, [1987] J. Comp. Neurol. 258:230–252; Watts et al. [1987] J. Comp. Neurol. 258:204–229). After retrograde tracer injections in the medial preoptic area, dorsomedial and paraventricular hypothalamic nuclei, bed nucleus of stria terminalis, paraventricular thalamic nucleus, zona incerta, and medial subparaventricular zone, retrogradely labeled SCN cells are clustered in the shell with few labeled neurons in the core. After injections centered in the lateral subparaventricular zone, peri‐suprachiasmatic region, lateral septum, or ventral tuberal area, the majority of neuronal label is in the core with moderate to sparse neuronal label in the shell. Both subdivisions are labeled after injections in the paratenial thalamic nucleus. The same pattern of retrograde labeling is found with four tracers, cholera toxin‐β subunit, Fluoro‐Gold, the Bartha strain of pseudorabies virus, and biotinylated dextran amine. These data extend our understanding of the significance of the division of the SCN into shell and core by demonstrating that the subdivisions differ in the pattern of projections. Together with prior observations that the subdivisions differ with respect to afferents, local connections, and neuroactive substances, the present study provides an anatomic basis for discrete control of circadian function by the SCN core and shell. In this novel view, the nature of the signal conveyed to areas receiving core or shell projections varies as a function of the subdivision from which innervation is derived. J. Comp. Neurol. 433:312–334, 2001. © 2001 Wiley‐Liss, Inc.