bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective separation of water from aqueous alcohol mixtures through functionalized syndiotactic poly(styrene‐co‐4‐methylstyrene) membranes by pervaporation
Authors: Li Chi‐Lan , Wang Yi‐Chieh , Kao Se‐Tsung , Fan Shu‐Chin , Lee Kueir‐Rarn , Lai Juin‐Yih
Published: October 2002

The pervaporation performances of a series of functionalized syndiotactic poly(styrene‐co‐4‐methylstyrene) (SPSM) membranes for various alcohol mixtures were investigated. The syndiotactic polystyrene copolymers, poly(styrene‐co‐4‐methylstyrene) (SPSM), were prepared by styrene with 4‐methylstyrene using a Cp*Ti(OCH3)3/methyl aluminoxane (metallocene/MAO) catalyst. The effect of functionalization on the thermal properties and polymer structure of the SPSM membranes were also investigated. The crystallinity of the functionalized SPSM membrane is lower than that of the unfunctionalized SPSM membranes. The water molecules preferentially permeate through the SPSM membranes. Compared with unfunctionalized SPSM membranes, the functionalized SPSM membrane effectively increases the membrane formation performances and the pervaporation performances. The optimun pervaporation performance (a separation factor of 510 and permeation rate of 220 g/m2h) was obtained by the bromination of SPSM (SPSMBr) membrane with a 90 wt % aqueous ethanol solution. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2247–2254, 2002
Low‐temperature hygrothermal degradation of ambient cured E‐glass/vinylester composites
Authors: Karbhari V. M. , Rivera J. , Zhang J.
Published: October 2002

Freeze and freeze‐thaw durability characteristics of fiber reinforced polymer (FRP) composites, especially in the presence of moisture, need to be investigated prior to the widespread implementation of these materials in civil, polar, and offshore structural components and systems. The hygrothermal degradation characteristics of an ambient cure E‐glass/vinylester system due to exposure to −10°C conditions and conditions of freeze‐thaw, including in the presence of water and seawater, was investigated. Changes in mechanical characteristics such as strength and modulus, and thermo‐mechanical dynamic characteristics such as storage and loss moduli, and glass‐transition temperature were measured, and short‐term effects of environmental exposure were assessed. It is seen that the presence of moisture/solution has a significant effect; both in terms of physical and chemical aging, and in terms of microcracking and fiber–matrix debond initiation. Results indicate the critical importance of cure characteristics and diffusion related phenomena. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2255–2260, 2002
Electric stimuli responses to poly(vinyl alcohol)/chitosan interpenetrating polymer network hydrogel in NaCl solutions
Authors: Kim Seon Jeong , Park Sang Jun , Kim In Young , Shin Mi‐Seon , Kim Sun I.
Published: October 2002

An interpenetrating polymer network (IPN) hydrogel composed of poly(vinyl alcohol) (PVA) and chitosan exhibited electric‐sensitive behavior. The PVA/chitosan IPN hydrogel was synthesized by an ultraviolet (UV) irradiation method that is used in several biomedical and industrial fields. The swelling behavior of the PVA/chitosan IPN hydrogel was studied by immersion of the gel in NaCl aqueous solutions at various concentrations. The swelling ratio decreased with increasing concentration of NaCl solution. The stimuli response of the IPN hydrogel in electric fields was also investigated. When a swollen PVA/chitosan IPN was placed between a pair of electrodes, the IPN exhibited bending behavior in response to the applied electric field. The bending angle and the bending speed of the PVA/chitosan IPN increased with increasing applied voltage and concentration of NaCl aqueous solution. The PVA/chitosan IPN also showed stepwise bending behavior depending on the electric stimulus. In addition, thermal properties of PVA/chitosan IPN were investigated by differential scanning calorimetry (DSC) and dielectric analysis (DEA). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2285–2289, 2002
Diffusion and sorption behavior of glycidyl methacrylate in styrene butadiene rubber
Authors: Hwang Kum Kang , Ryu Sung Hun , Hong Seong Uk
Published: October 2002

In this study, the diffusion and sorption behavior of glycidyl methacrylate in styrene butadiene rubber (SBR) was investigated as a function of waste tire powder content, sulfur content (i.e., the crosslink density), and temperature by using the gravimetric sorption method. The results indicate that penetrant solubility increases as sulfur and waste tire powder contents decrease, whereas the temperature affects the solubility favorably. The results also indicate that mutual diffusion coefficients decrease as the sulfur and waste tire powder contents increase. This behavior was interpreted in terms of free volume of the polymer and tortuosity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2701–2706, 2002
Mixed radiation field effects from a nuclear reactor on poly(aryl ether ether ketone): A melt viscosity study
Authors: Pagé D. J. Y. S. , Bonin H. W. , Bui V. T. , Bates P. J.
Published: October 2002

Poly(aryl ether ether ketone) (PEEK) is a high‐temperature engineering thermoplastic used in the aerospace industry. To assess its suitability for nuclear industry applications, the effects of mixed field radiation from a nuclear reactor were investigated on two industrial semicrystalline PEEK grades (VICTREX 150P and 450P). Specimens were first processed on an ENGEL55 injection molder and then irradiated in the pool of a SLOWPOKE‐2 nuclear research reactor. Specimens were thus exposed to a mixed field of radiation including gamma, electrons, protons, and neutrons, for exposures resulting in doses ranging from 0.15 to 15 MGy. Irradiated samples were characterized by viscosity measurements in the melt, differential scanning calorimetry (DSC), and density measurements. Melt viscosity of irradiated samples proved to be significant in detecting early molecular weight changes in PEEK and helped explain the interaction of competing chain scission and crosslinking reactions at various stages of the radiolysis. All results pointed toward the following transformation of the resin with increased dosage: chain scission of the tie‐molecules between the amorphous and crystalline phases, crosslinking in the amorphous phase, followed by a general degradation of the molecular weight dominated by chain‐scission. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2713–2719, 2002
Biodegradation of nylon4 and its blend with nylon6
Authors: Hashimoto Kazuhiko , Sudo Mie , Ohta Kazumi , Sugimura Takayuki , Yamada Hiroyuki , Aoki Takayuki
Published: October 2002

The nylon4 portion in the blend films composed of nylon4 and nylon6 was degraded and completely disappeared within 4 months in two kinds of composted soils gathered from different university farms as well as pure nylon4 film reported previously, while the nylon6 portion remained even after the burial test for 15 months. Nylon4 powder was also degraded to carbon dioxide in the degradation test in an activated sludge obtained from a sewage disposal institution in Kogakuin University. Three species of microoganisms (i.e., ascomytous fungi) were isolated through the inoculation from the nylon4 film partially degraded in the soil on a medium containing nylon4 powder as a carbon source. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2307–2311, 2002
Synthesis and characterization of chitosan alkyl carbamates
Authors: Cárdenas Galo , Paredes Juan C. , Cabrera Gustavo , Casals Pedro
Published: October 2002

The synthesis of chitosan methylcarbamate (ChMC) and ethylcarbamate (ChEC) is described by using a new methodology. Polymers with substitution degrees up to 63% for ChEC and 68.5% for ChMC were obtained. Derivatives with lower substitutions were acid soluble but those with higher ones were completely insoluble. This could be due to the loss in hydrophilic sites when the substitution degree increases. The reaction conditions and degree of substitution obtained for both derivatives were also described. A complete chemical characterization was carried out by spectroscopic techniques. The thermal degradation of chitosan and derivatives were studied in the range 25–500°C and both derivatives were shown to be thermally less stable than chitosan. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2742–2747, 2002
Factors affecting the interfacial polymerization of polyamide active layers for the formation of polyamide composite membranes
Authors: Jegal Jonggeon , Min Sung Gyu , Lee Kew‐Ho
Published: October 2002

Polyamide (PA) composite membranes were prepared by interfacial polymerization with piperazine, m‐phenylene diamine, and trimesoyl chloride as monomers and polysulfone ultrafiltration membranes as supports. Factors affecting the performances of the composite membranes by changing the characteristics of the PA active layers were studied. First, the monomer compositions were varied, and organic solvents (benzene and 1,2‐dichloroethane) with better solubility for PA than hexane were used for the interfacial polymerization. As chemical additives capable of changing the property of the interface formed between water and organic phases, n‐propanol and i‐propanol were used, and phase‐transfer catalysts such as triethyl benzyl ammonium bromide were used to improve the polymerization efficiency of the PA active layers. The characteristics of the PA composite membranes prepared, including their permeation properties and morphology, were carefully studied with various analytical methods, such as field emission scanning microscopy, atomic force microscopy, differential scanning calorimetry, and permeation testing. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2781–2787, 2002
Effects of molecular architecture on two‐step, melt‐spun poly(lactic acid) fibers
Authors: Cicero John A. , Dorgan John R. , Garrett James , Runt James , Lin J. S.
Published: October 2002

Fibers of poly(lactic acid) (PLA) produced by two‐step melt spinning have been studied. The PLA resins used contain a 96:04 ratio of L:D stereochemical centers; however, one of the materials is branched by a peroxide treatment. The thermal, mechanical, and morphological properties of the fibers are compared for the two different molecular architectures. In the branched material, at least some of the branches exceed the entanglement molecular weight. The branched material is accordingly characterized by greater shear and extensional viscosity than the linear material. Fiber properties are highly influenced by the draw ratio; both branched and linear materials reach a plateau of about 35% crystallinity. The branched polymer reaches the plateau at a lower draw ratio, and this is indicative of faster crystallization kinetics. Both materials shrink in boiling water, and the amount of shrinkage decreases with increasing draw ratio. At an intermediate draw ratio of 6, the branched material is characterized by significantly larger shrinkage. With small‐angle X‐ray scattering and atomic force microscopy, the morphology is found to be fibrillar. Microfibril diameters range from approximately 20 to 30 nm and are almost identical for the two molecular architectures studied. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2839–2846, 2002
Novel polyisobutylene stars. XXIII. Thermal, mechanical, and processing characteristics of poly(phenylene ether)/polydivinylbenzene(polyisobutylene‐b‐polystyrene)37 blends
Authors: Asthana S. , Kennedy J. P.
Published: October 2002

The objective of these investigations was to increase the use temperature of novel star‐block polymers consisting of a crosslinked polydivinylbenzene (PDVB) core from which radiate multiple poly(isobutylene‐b‐polystyrene) (PIB‐b‐PSt) arms, abbreviated by PDVB(PIB‐b‐PSt)n. We achieved this objective by blending star‐blocks with poly(phenylene oxide) (PPO) that is miscible with PSt. Thus, various PPO/PDVB(PIB‐b‐PSt)n blends were prepared, and their thermal, mechanical, and processing properties were investigated. The hard‐phase glass‐transition temperature of the blends could be controlled by the amount (wt %) of PPO. The blends displayed superior retention of tensile strengths at high temperatures as compared to star blocks. The melt viscosities of blends with low weight percentages of PPO were lower than those of star blocks. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2866–2872, 2002
Tensile properties, morphology, and biodegradability of blends of starch with various thermoplastics
Authors: Park Hwan‐Man , Lee Sang‐Rock , Chowdhury Subhendu R. , Kang Tae‐Kyu , Kim Hak‐Kil , Park Seung‐Hoon , Ha Chang‐Sik
Published: October 2002

In the present study, blends of starch with different thermoplastics were prepared by a melt blending technique. The tensile properties and morphology of the blends were measured. It was found that with increasing starch content in starch/ionomer blends, the tensile strength and modulus increase. But for starch/low‐density polyethylene (LDPE) and starch/aliphatic polyester (APES) blends, tensile strength and modulus decrease with increasing the starch loading. Elongation at break values of all the blend systems decrease with increasing starch loading. The scanning electron micrographs (SEM) support the findings of tensile properties. Better homogeneity is observed in starch/ionomer systems compared with that in starch/APES and starch/LDPE systems. Up to 50% starch content, the starch/ionomer blends appear as a single phase. The extent of phase interactions of starch/APES system lies in between the starch/LDPE and starch/ionomer systems. From the biodegradability studies of the blends it was found that, although the pure LDPE and ionomer are not biodegradable, the starch/LDPE and starch/ionomer blends are biodegradable with an appreciable rate. The rate of biodegradation of the starch/APES is very high as both the components are biodegradable. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2907–2915, 2002
Antiinflammatory effect of retrovirally transfected interleukin‐10 on monosodium urate monohydrate crystal–induced acute inflammation in murine air pouches
Authors: Murakami Yousuke , Akahoshi Tohru , Kawai Shinichi , Inoue Matsuhisa , Kitasato Hidero
Published: October 2002

Objective

To investigate the role of interleukin‐10 (IL‐10) in the inflammatory response, the antiinflammatory effect of retrovirally transfected IL‐10 was evaluated both in vitro and in vivo.

Methods

A recombinant retrovirus containing the murine IL‐10 gene was constructed using the pLXSN vector and was designated as LXSN‐IL‐10. Murine IL‐10 was introduced into embryonic C57BL/6J fibroblast cells using LXSN‐IL‐10 to create C57‐IL‐10 cells. The effect of IL‐10 in the culture supernatant of these cells was then evaluated by determining changes in the production of tumor necrosis factor α (TNFα), macrophage inflammatory protein 1α (MIP‐1α), and MIP‐1β by macrophages. The antiinflammatory effect of C57‐IL‐10 cells was also investigated using an in vivo model of monosodium urate monohydrate (MSU) crystal–induced acute inflammation.

Results

The IL‐10 gene transcript and its product were detected by reverse transcriptase–polymerase chain reaction and enzyme‐linked immunosorbent assay, respectively. The level of IL‐10 in the culture supernatant of C57‐IL‐10 cells was estimated to be 50 ng/ml. The culture supernatant of these cells exerted the biologic activity of IL‐10, showing inhibition of TNFα, MIP‐1α, and MIP‐1β production by macrophages. Injection of C57‐IL‐10 cells into murine air pouches significantly inhibited MSU crystal–induced cellular infiltration (P < 0.01) and production of the mouse CXC chemokine KC (P < 0.05). These findings were consistent with the results obtained by the injection of recombinant human IL‐10 into air pouches.

Conclusion

In this murine air pouch model of MSU crystal–induced inflammation, IL‐10 seemed to inhibit the recruitment of neutrophils at least partly by suppressing KC production. These findings seem to suggest that IL‐10 gene therapy may be useful for inflammatory diseases.
Modeling the progression of rheumatoid arthritis: A two‐country model to estimate costs and consequences of rheumatoid arthritis
Authors: Kobelt Gisela , Jönsson Linus , Lindgren Peter , Young Adam , Eberhardt Kerstin
Published: October 2002

Objective

Two simulation models were developed to analyze the cost‐effectiveness of new treatments that affect the progression of rheumatoid arthritis (RA).

Methods

We used data from 2 cohorts of patients with early RA who had been followed up since disease onset (up to 15 years). In the Swedish study, 183 patients were followed up for a mean of 11.3 years. In the UK study, 916 patients were followed up for a mean of 7.8 years. Disease progression over 10 years was modeled as annual transitions between disease states, defined by Health Assessment Questionnaire (HAQ) scores. A regression model was used to estimate transition probabilities conditional on age, sex, and time since onset of disease, in order to allow simulation of different patient cohorts. Costs and utilities associated with different HAQ levels were based on data from the cohort studies and cross‐sectional surveys.

Results

Costs increase and quality of life decreases as RA progresses. In Sweden, total annual costs range from $4,900 to $33,000 per patient, compared with $4,900 to $14,600 in the UK. Cumulative costs over 10 years for patients starting in disease state 1 (HAQ < 0.6) are $54,600 in Sweden and $26,600 in the UK. The cumulative numbers of quality‐adjusted life‐years (QALYs) are 5.5 and 5.6, respectively. Both costs and QALYs were discounted at 3%.

Conclusion

The 2 models, which were based on different patient cohorts, reach a similar conclusion in terms of the effect of RA over 10 years. They appear to accurately capture disease progression and its effects and can therefore be useful in estimating the cost‐effectiveness of new treatments in RA.
A pilot randomized trial comparing CD34‐selected versus unmanipulated hemopoietic stem cell transplantation for severe, refractory rheumatoid arthritis
Authors: Moore John , Brooks Peter , Milliken Sam , Biggs Jim , Ma David , Handel Malcolm , Cannell Paul , Will Rob , Rule Simon , Joske David , Langlands Bob , Taylor Kerry , O'Callaghan Joe , Szer Jeff , Wicks Ian , McColl Geoff , Passeullo Frances , Snowden John
Published: October 2002

Objective

Evidence from animal studies, case reports, and phase I studies suggests that hemopoietic stem cell transplantation (HSCT) can be effective in the treatment of rheumatoid arthritis (RA). It is unclear, however, if depletion of T cells in the stem cell product infused after high‐dose chemotherapy is beneficial in prolonging responses by reducing the number of infused autoreactive T cells. This pilot multicenter, randomized trial was undertaken to obtain feasibility data on whether CD34 selection (as a form of T cell depletion) of an autologous stem cell graft is of benefit in the HSCT procedure in patients with severe, refractory RA.

Methods

Thirty‐three patients with severe RA who had been treated unsuccessfully with methotrexate and at least 1 other disease‐modifying agent were enrolled in the trial. The patients received high‐dose immunosuppressive treatment with 200 mg/kg cyclophosphamide followed by an infusion of autologous stem cells that were CD34 selected or unmanipulated. Safety, efficacy (based on American College of Rheumatology [ACR] response criteria), and time to recurrence of disease were assessed on a monthly basis for up to 12 months.

Results

All patients were living at the end of the study, with no major unexpected toxicities. Overall, on an intent‐to‐treat basis, ACR 20% response (ACR20) was achieved in 70% of the patients. An ACR70 response was attained in 27.7% of the 18 patients who had received CD34‐selected cells and 53.3% of the 15 who had received unmanipulated cells (P = 0.20). The median time to disease recurrence was 147 days in the CD34‐selected cell group and 201 days in the unmanipulated cell group (P = 0.28). There was no relationship between CD4 lymphopenia and response, but 72% of rheumatoid factor (RF)–positive patients had an increase in RF titer prior to recurrence of disease.

Conclusion

HSCT can be performed safely in patients with RA, and initial results indicate significant responses in patients with severe, treatment‐resistant disease. Similar outcomes were observed in patients undergoing HSCT with unmanipulated cells and those receiving CD34‐selected cells. Larger studies are needed to confirm these findings.
Autoantibodies against granulocyte colony‐stimulating factor in Felty's syndrome and neutropenic systemic lupus erythematosus
Authors: Hellmich Bernhard , Csernok Elena , Schatz Helmut , Gross Wolfgang L. , Schnabel Armin
Published: October 2002

Objective

Cytokines and growth factors can be a target of autoantibodies in systemic inflammatory diseases. We examined whether patients with neutropenia and either Felty's syndrome (FS) or systemic lupus erythematosus (SLE) have autoantibodies against granulocyte colony‐stimulating factor (G‐CSF) and whether these autoantibodies are functionally relevant.

Methods

Fifteen patients with neutropenia due to FS were matched for age, sex, and disease activity with 16 normocytic rheumatoid arthritis (RA) control patients. Sixteen patients with SLE and neutropenia were matched with 16 normocytic SLE control patients. Antibodies against G‐CSF were measured by enzyme‐linked immunosorbent assay and Western blotting. Antibody specificity was verified by competitive inhibition using recombinant human G‐CSF. The effect of anti–G‐CSF antibodies on the functional activity of their target molecule was measured in a bioassay using G‐CSF–sensitive murine 32D cells.

Results

IgG anti–G‐CSF was found in 11 FS patients, 6 SLE patients with neutropenia, 6 SLE control patients, and none of the RA control patients. IgM anti–G‐CSF was found in 6 neutropenic and 3 normocytic SLE patients. Anti–G‐CSF antibodies were associated with an exaggerated serum level of G‐CSF and a low neutrophil count. A neutralizing effect of anti–G‐CSF antibodies on its target molecule was found in 3 of the 9 patients tested. Irrespective of the presence or absence of anti–G‐CSF antibodies, neutropenic patients with FS and SLE had exaggerated serum levels of G‐CSF.

Conclusion

Anti–G‐CSF autoantibodies are common in neutropenia due to FS and SLE. In individual patients, these autoantibodies have a neutralizing capacity. In patients without neutralizing antibodies, hyposensitivity of the myeloid cells to G‐CSF appears to be central to the pathogenesis of the neutropenia in FS and SLE.
Association of mutations in the NALP3/CIAS1/PYPAF1 gene with a broad phenotype including recurrent fever, cold sensitivity, sensorineural deafness, and AA amyloidosis
Authors: Aganna Ebun , Martinon Fabio , Hawkins Philip N. , Ross John B. , Swan Daniel C. , Booth David R. , Lachmann Helen J. , Gaudet Roxanne , Woo Patricia , Feighery Conleth , Cotter Finbarr E. , Thome Margot , Hitman Graham A. , Tschopp Jürg , McDermott Michael F.
Published: October 2002

Objective

Familial cold urticaria (FCU) and Muckle‐Wells syndrome (MWS) are dominantly inherited autoinflammatory disorders that cause rashes, fever, arthralgia, and in some subjects, AA amyloidosis, and have been mapped to chromosome 1q44. Sensorineural deafness in MWS, and provocation of symptoms by cold in FCU, are distinctive features. This study was undertaken to characterize the genetic basis of FCU, MWS, and an overlapping disorder in French Canadian, British, and Indian families, respectively.

Methods

Mutations in the candidate gene NALP3, which has also been named CIAS1 and PYPAF1, were sought in the study families, in a British/Spanish patient with apparent sporadic MWS, and in matched population controls. Identified variants were sought in 50 European subjects with uncharacterized, apparently sporadic periodic fever syndromes, 48 subjects with rheumatoid arthritis (RA), and 19 subjects with juvenile idiopathic arthritis (JIA).

Results

Point mutations, encoding putative protein variants R262W and L307P, were present in all affected members of the Indian and French Canadian families, respectively, but not in controls. The R262W variant was also present in the subject with sporadic MWS. The V200M variant was present in all affected members of the British family with MWS, in 2 of the 50 subjects with uncharacterized periodic fevers, and in 1 of 130 Caucasian and 2 of 48 Indian healthy controls. No mutations were identified among the subjects with RA or JIA.

Conclusion

These findings confirm that mutations in the NALP3/CIAS1/PYPAF1 gene are associated with FCU and MWS, and that disease severity and clinical features may differ substantially within and between families. Analysis of this gene will improve classification of patients with inherited or apparently sporadic periodic fever syndromes.
Pharmacological and pharmacokinetic evaluation of celecoxib prodrugs in rats
Authors: Mamidi Rao N.V.S. , Mullangi Ramesh , Kota Jagannath , Bhamidipati Ravikanth , Khan Ansar A. , Katneni Kasiram , Datla Srinivasaraju , Singh Sunil K. , Rao Koteswar Y. , Seshagiri Rao C. , Srinivas Nuggehally R. , Rajagopalan Ramanujam
Published: October 2002

This study demonstrates the utility of an in vitro – in vivo correlative approach in the selection and optimization of a prodrug candidate of celecoxib (CBX), a COX2 inhibitor. As an initial screening step, a comparative single oral dose pharmacokinetic study was conducted in rats for CBX and its three aliphatic acyl water‐soluble prodrugs viz., CBX‐acetyl (CBX‐AC), CBX‐propionyl (CBX‐PR) and CBX‐butyryl (CBX‐BU) at high equimolar dose, 100 mg/kg. Only CBX‐BU and CBX‐PR converted rapidly to CBX and yielded approximately five‐fold greater systemic exposure of CBX than CBX alone or CBX‐AC. Rank order of systemic exposure of prodrugs in its intact form was CBX‐AC >CBX‐PR >CBX‐BU. Further in vitro hydrolysis studies of CBX prodrugs in intestinal mucosal suspensions and liver homogenates indicated that CBX‐BU is rapidly and completely converted to CBX, whereas CBX‐PR and CBX‐AC require longer incubation period for complete conversion to CBX. There was a very good correlation of the in vitro and in vivo data supporting CBX‐BU as the prodrug of choice. Further in vitro pharmacological studies showed that COX2 selective inhibition is improved for CBX‐BU as compared to CBX‐AC and CBX‐PR. Dose proportionality in pharmacokinetic studies of CBX‐BU and CBX at equimolar oral doses confirmed that relative oral bioavailability of CBX was improved following CBX‐BU administration and there was linearity in pharmacokinetics of CBX over a wide dose range (10–100 mg/kg), whereas CBX in its conventional form showed poor bioavailability and lack of dose linearity in pharmacokinetics. The oral bioavailability of CBX from CBX‐BU was dose independent and was in the range 78–96%. At a 50% reduced molar dose, CBX‐BU showed an equivalent efficacy to that of CBX in the in vivo carrageenan model. Based on the study, water‐soluble CBX‐BU prodrug can be considered for clinical development in view of its potential advantages.Copyright © 2002 John Wiley & Sons, Ltd.
Pharmacokinetics and tissue distribution of intravenous pefloxacin for antibiotic prophylaxis in biliary surgery
Authors: Gascón A.R. , Campo E. , Olea E. , Hernández R.M. , Calvo B. , Errasti J. , Pedraz J.L.
Published: October 2002

The plasma levels and tissue penetration of pefloxacin were studied after prophylactic administration to patients undergoing elective biliary surgery. Pefloxacin was administered as a single dose of 800 mg given intravenously as an infusion 1 h before surgery. Over a period of two years, cultures of bile and stone were performed after cholecystectomy in order to find the main pathogens present in the geographical area of the hospital of Txagorritxu (Vitoria, Spain), as well as to test the antimicrobial susceptibility of these bacteria to pefloxacin. Thirty seven per cent of the bile and stone cultures were positive, and 75 different species were isolated. E. coli was the predominant microorganism (25%). Other frequent microorganisms were E. faecium (9.3%), S. epidermidis (6.6%) and Cl. perfringens (6.6%). Most species isolated were susceptible to pefloxacin, with MIC90 values of 0.125 μg/ml for E. coli, 0.5 μg/ml for S. epidermidis and 1 μg/ml for Cl. perfringens. E. faecium was resistant, with a MIC90 value of 8 μg/ml but a MIC50 of 4 μg/ml (intermediate). After pefloxacin infusion, adequate drug plasma levels (>MIC90) for the most frequent pathogens were found throughout the procedure. Elimination half‐life was estimated as 22.03±6.91 h; the area under the concentration–time curve from zero to infinite had a value of 275.07±130.02 mg h/l and the values for volume of distribution at steady‐state and plasma clearance were 96.48±28.65 L and 3.60±1.83 l/h, respectively. Bile pefloxacin concentrations generally exceeded the minimum inhibitory concentrations for most relevant pathogens. Drug levels in gallbladder and subcutaneous tissues were also above the MIC90 for extended periods. Patients were observed daily throughout their hospital stay. This included examination of the surgical wound and recording of body temperature. No cases of anaerobic infection were noted in the study patients. Other constants such as hospitalization stay and time of recuperation were normal for this type of surgery. According to these results, pefloxacin presents many features that make it suitable for use as a therapeutic prophylactic agent, such as its broad spectrum of antimicrobial activity and favorable pharmacokinetic properties. Copyright © 2002 John Wiley & Sons, Ltd.
Disposition of acamprosate in the rat: Influence of probenecid
Authors: Zornoza Teodoro , Guerri Consuelo , Polache Ana , Granero Luis
Published: October 2002

The purpose of the present study was to investigate the disposition of acamprosate (calcium bis acetyl‐homotaurine) in the rat. Initially, we studied the linearity of acamprosate disposition and the fraction of acamprosate excreted unchanged in the urine of the animals. Rats received 9.3, 36.6 or 73.3 mg/kg of the drug as an intravenous bolus. The statistical analysis of the pharmacokinetic parameters did not reveal any significant difference, indicating that acamprosate disposition was linear within the range of the doses assayed. On average, 95% of the administered dose was excreted unchanged in the urine of the animals in the 0–6 h post‐administration period indicating that renal excretion is the main elimination route for this drug. Acamprosate was also administered by the intravenous route at three different constant infusion rates (2.65, 132.5 and 530 μg/min) in order to quantify total (Clt) and renal (Clr) plasma clearances at steady‐state conditions. The mean Clr values were, respectively, 4.60±0.42, 4.28±0.52 and 4.08±0.67 ml/min, practically equivalent to the Clt values (4.78±0.38, 4.51±0.36 and 4.21±0.56 ml/min), confirming that the drug is mainly eliminated via renal excretion. Moreover, Clr values were clearly higher than the glomerular filtration rate (2.61±0.26 ml/min), suggesting the existence of a highly efficient tubular secretion mechanism in the renal excretion of the drug. To confirm this hypothesis, two groups of rats were intravenously treated with probenecid (33.3 or 66.6 mg/kg) prior to acamprosate administration (9.3 mg/kg). Probenecid provoked a statistically significant dose‐dependent reduction in the total clearance of acamprosate (from 5.8±0.7 ml/min in the control group to 2.6±0.1 ml/min in the animals treated with 66 mg/kg of probenecid) demonstrating the existence of a tubular secretion process on the renal excretion of acamprosate in the rat. Copyright © 2002 John Wiley & Sons, Ltd.
Out of Africa with regional interbreeding? Modern human origins
Authors: Satta Yoko , Takahata Naoyuki
Published: October 2002

A central issue in paleoanthropology is whether modern humans emerged in a single geographic area and subsequently replaced the preexisting people in other areas. Although the study of human mitochondrial DNAs supported this single‐origin and complete‐replacement model, a recent paper1 argues that humans expanded out of Africa more than once and regionally interbred. However, both the genetic antiquity and the impact of the African contribution to modern Homo sapiens are so great as to view Africa as a central place of human evolution. Despite the possibility that out‐of‐Africa H. sapiens interbred with other populations, this evidence is more consistent with the uniregional hypothesis than the multiregional hypothesis of modern human origins. BioEssays 24:871–875, 2002. © 2002 Wiley Periodicals, Inc.
Bioreduction and biocrystallization of palladium by Desulfovibrio desulfuricans NCIMB 8307
Authors: Yong Ping , Rowson Neil A. , Farr J. Peter G. , Harris I. Rex , Macaskie Lynne E.
Published: October 2002

The reduction of Pd(II) to Pd(0) was accelerated by using the sulfate‐reducing bacterium Desulfovibrio desulfuricans NCIMB 8307 at the expense of formate or H2 as electron donors at pH 2–7. With formate no reduction occurred at pH 2, but with H2 50% of the activity was retained at pH 2, with the maximum rate (1.3–1.4 μ mol min−1 mg dry cells−1) seen at pH 3–7, which was similar to the rate with formate at neutral pH. Excess nitrate was inhibitory to Pd(II) reduction using formate, but not H2. Chloride ion was inhibitory as low as 100 mM using formate but with H2 only ca. 25% inhibition was observed at 500 mM Cl− and H2 was concluded to be the electron donor of choice for the potential remediation of industrial wastes. Deposited Pd was visible on the cells using transmission and scanning electron microscopy and analysis by energy dispersive X‐ray microanalysis (EDAX) identified the deposit as Pd, confirmed as Pd(0) by X‐ray powder diffraction analysis (XRD). The crystal size of the biodeposited Pd(0) was determined to be only 50% of the size of Pd(0) crystals manufactured chemically from Pd(II) at the expense of H2 and, unlike the chemically manufactured material, the biocrystal size was independent of the pH. The “biological” Pd(0) functioned as a superior chemical catalyst in a test reaction which liberated hydrogen from hypophosphite. Pd, and also Pt and Rh, could be recovered by resting cell suspensions under H2 from an industrial processing wastewater, suggesting a possible future application of bioprocessing technology for precious metals. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 369–379, 2002.
Scale‐up and optimization of an acoustic filter for 200 L/day perfusion of a CHO cell culture
Authors: Gorenflo Volker M. , Smith Laura , Dedinsky Bob , Persson Bo , Piret James M.
Published: October 2002

Acoustic cell retention devices have provided a practical alternative for up to 50 L/day perfusion cultures but further scale‐up has been limited. A novel temperature‐controlled and larger‐scale acoustic separator was evaluated at up to 400 L/day for a 107 CHO cell/mL perfusion culture using a 100‐L bioreactor that produced up to 34 g/day recombinant protein. The increased active volume of this scaled‐up separator was divided into four parallel compartments for improved fluid dynamics. Operational settings of the acoustic separator were optimized and the limits of robust operations explored. The performance was not influenced over wide ranges of duty cycle stop and run times. The maximum performance of 96% separation efficiency at 200 L/day was obtained by setting the separator temperature to 35.1°C, the recirculation rate to three times the harvest rate, and the power to 90 W. While there was no detectable effect on culture viability, viable cells were selectively retained, especially at 50 L/day, where there was a 5‐fold higher nonviable washout efficiency. Overall, the new temperature‐controlled and scaled‐up separator design performed reliably in a way similar to smaller‐scale acoustic separators. These results provide strong support for the feasibility of much greater scale‐up of acoustic separations. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 438–444, 2002.
Purification of a functional gene therapy vector derived from Moloney murine leukaemia virus using membrane filtration and ceramic hydroxyapatite chromatography
Authors: Kuiper Marcel , Sanches Raquel M. , Walford James A. , Slater Nigel K.H.
Published: October 2002

The ability of membrane ultra‐ and diafiltration and two chromatography media, Matrex⌖ Cellufine™ Sulfate (Millipore) and Macro‐Prep⌖ ceramic hydroxyapatite (Bio‐Rad), to adsorb, elute, and purify gene therapy vectors based on Moloney murine leukaemia virus (MoMuLV) carrying the 4070A amphotropic envelope protein was studied. Membrane ultra‐ and diafiltration provided virus concentration up to 160‐fold with an average recovery of infectious viruses of 77 ± 14%. In batch experiments, Macro‐Prep⌖ ceramic hydroxyapatite (type 2, particle size 40 μm) proved superior to Matrex⌖ Cellufine™ Sulfate for MoMuLV vector particle adsorption. Furthermore, functional vector particles could be eluted using phosphate buffer pH 6.8 (highest titres from ≥300 mM phosphate) from the Macro‐Prep⌖ adsorbent, with higher specific titres (cfu/mg protein) than the starting material. Similar results were obtained when this ceramic hydroxyapatite was packed into a column and used in a liquid chromatography system. Recovery of transduction‐competent virus was between 18 and 31% for column experiments and 32 and 46% for batch experiments. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 445–453, 2002.
Solvent selection for solid‐to‐solid synthesis
Authors: Ulijn Rein V. , De Martin Luigi , Gardossi Lucia , Janssen Anja E. M. , Moore Barry D. , Halling Peter J.
Published: October 2002

Thermolysin catalyzed solid‐to‐solid synthesis of the model peptide Z‐L‐Phe‐L‐Leu‐NH2 is practically feasible in water and a range of organic solvents with different physicochemical properties. Excellent overall conversions were obtained in acetonitrile, ethyl acetate, n‐hexane, methanol, 2‐propanol, tert‐amyl alcohol, tetrahydrofuran, toluene and water, while no product precipitation was observed in dichloromethane resulting in a much lower yield. In precipitation driven synthesis the product accumulates both in solution and in the solid phase. It was shown that the highest overall yields (yield in the liquid plus yield in the solid) can be expected in solvents where the substrate solubilities are minimized. The best yields of solid product can be expected in solvents where both product and substrate solubilities are lowest. This was in agreement with experimental observations and should be generally valid. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 509–515, 2002.
Changing a culture: a brief program analysis of a social learning program on a maximum‐security forensic unit
Authors: Goodness Kelly R. , Renfro Nancy S.
Published: October 2002

This report presents outcome data collected for a three‐year period from a maximum‐security forensic psychiatric program. Admission and discharge variables, restraint/seclusion, and client abuse/neglect data are presented from a one‐year period that preceded the advent of the Behavior Management Treatment Program's (BMTP's) Social Learning Diagnostic Program to two years after implementing the Social Learning Diagnostic Program. Significant overall progress and improvement was observed in all variables analyzed after instituting a social learning program paradigm. This report provides a brief summary of the BMTP's Social Learning Diagnostic Program along with a discussion of the role played by Dangerousness Management Plans in the treatment of patients within the social learning milieu. Additionally the patient population served, and the rationale for implementation of a program based in social learning theory, are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Intravascular ultrasound catheter entrapment after coronary artery stenting
Authors: Sasseen Brett M. , Burke James A. , Shah Rakesh , Costa Marco A. , Zenni Martin , Gilmore Paul , Bass Theodore A.
Published: October 2002

Intracoronary ultrasound (IVUS) facilitates optimal stent deployment in the treatment of coronary artery disease, which may favorably improve long‐term outcome after stenting. Complications associated with IVUS include coronary vasospasm and rarely more serious adverse events such as vessel perforation or stent deformation. We report an IVUS catheter tip entrapment within a self‐deploying nitinol stent. Cathet Cardiovasc Intervent 2002;57:229–233. © 2002 Wiley‐Liss, Inc.
Percutaneous transcatheter coil embolization of two coronary fistulas originating from the left main ostium and left anterior descending artery
Authors: Boccalandro Fernando , Awadalla Hany , Smalling Richard W.
Published: October 2002

We report a successful case of percutaneous transcatheter coil embolization of a coronary fistula originating from the ostium of the left main, simultaneously with a second fistula arising from the left anterior descending artery, in a patient with exercise‐related angina and evidence of myocardial ischemia. Cathet Cardiovasc Intervent 2002;57:221–223. © 2002 Wiley‐Liss, Inc.
A new Amplatzer device to maintain patency of Fontan fenestrations and atrial septal defects
Authors: Amin Zahid , Danford David A. , Pedra Carlos A.C.
Published: October 2002

This study evaluated use of Amplatzer fenestrated device to maintain patency of the Fontan fenestration and atrial septal defect. Fenestrations are routinely created in patients with lateral tunnel or extracardiac Fontan. Spontaneous closure of the fenestration can lead to Fontan circulation failure. Other patients without single‐ventricle physiology may benefit from a small communication between the left and right atria for decompression if closure of the atrial septal defect leads to failure of a dysfunctional ventricle. Amplatzer septal occluder device was modified to create a fenestration through the disks. Three patients with modified Fontan and one patient with a large atrial septal defect underwent placement of the device by transcatheter technique. The device deployment was guided by transesophageal echocardiography. The procedure was successful in all patients. Contrast injection after placement revealed patent fenestration with free flow. Follow‐up ranged from 3 months to 1 year. All devices were patent by transthoracic echocardiography. These preliminary results suggest that the Amplatzer fenestrated device can serve as a valuable tool in failing Fontan circulation and may help to avoid surgical intervention. More studies are needed to assess long‐term efficacy of the device. Cathet Cardiovasc Intervent 2002;57:246–251. © 2002 Wiley‐Liss, Inc.
Architecture and function of atropisomeric molecular triads
Authors: Gawroński J. , Kacprzak K.
Published: October 2002

Molecular triads, B‐A‐B, in which the central unit A is aromatic or heteroaromatic, can exist as syn or anti conformers or atropisomers of correspondingly C or S shape. These stereoisomers are either discrete conformer species, often distinguished by NMR spectroscopy, or can be separated at ambient temperature as stable atropisomers. In the latter case syn and anti stereoisomers exhibit different (e.g., complex‐forming) properties. Practical applications of atropisomeric triads as ligands in asymmetric dihydroxylation are also discussed. Chirality 14:689–702, 2002.
Cancer among Hispanic women in South Florida: An 18‐year assessment
Authors: Wilkinson James D. , Wohler‐Torres Bradley , Trapido Edward , Fleming Lora E. , MacKinnon Jill , Peace Steven
Published: October 2002

BACKGROUND

The Hispanic population now represents the majority of residents in Miami‐Dade County, Florida. The authors present cancer incidence and mortality data for South Florida's Hispanic women for the period 1990–1998 and compare these data to previously reported data from 1981–1989. Cancer incidence, risk, and mortality data should reflect current population distribution, lifestyle, and environmental risk factors so that cancer prevention and control activities are informed optimally.

METHODS

The study population consisted of all women with malignant disease during 1981–1998 from Miami‐Dade County found in the Florida Cancer Data System data base; patients were divided into 2 9‐year periods for analysis. Age‐standardized incidence and mortality rates were computed for common disease sites; rates for Hispanic women were compared with the rates for non‐Hispanic white (NHW) women as standardized rate ratios (SRR) with 95% confidence intervals (95%CIs). Incidence and mortality trends were analyzed using linear regression.

RESULTS

Over 70,000 cancer incidents were analyzed. The overall decreased cancer risk for Hispanic women (SRR, 0.65; 95%CI, 0.64–0.67), compared with NHW women, remained essentially constant over the two study periods. Cancer incidence increased similarly for the two racial‐ethnic groups. The incidence of lung carcinoma increased in both groups, becoming the second most common disease site for NHW women and the third most common disease site for Hispanic women.

CONCLUSIONS

The decreased relative cancer risk for Hispanic women in South Florida has remained stable over the past 18 years. Lung carcinoma is increasing among women in both racial‐ethnic groups. Cancer 2002;95:1752–8. © 2002 American Cancer Society.

DOI 10.1002/cncr.10834
A lymph node metastatic mouse model reveals alterations of metastasis‐related gene expression in metastatic human oral carcinoma sublines selected from a poorly metastatic parental cell line
Authors: Zhang Xin , Liu Yanna , Gilcrease Michael Z. , Yuan Xiao H. , Clayman Gary L. , Adler‐Storthz Karen , Chen Zhuo
Published: October 2002

BACKGROUND

Greater than 40% of patients with squamous cell carcinoma (SCC) of the oral cavity have lymph node metastasis at the time of diagnosis and a 5‐year survival rate of less than 50%. Changes in gene expression that regulate metastasis of SCC to lymph nodes have not been identified.

METHODS

To study metastasis of oral SCC, highly metastatic oral SCC cell lines from a poorly metastatic oral SCC cell line were established by in vivo selection using a lymph node metastatic mouse model. The metastatic potential of the cells was studied using Matrigel invasion and cell surface protein adhesion assays. mRNA and protein encoded from metastasis‐related genes in the metastatic derivatives and in their parental cells were examined using Northern blot analysis, immunoblotting, rapid analysis of gene expression, and a cDNA microarray technique.

RESULTS

The in vivo selected metastatic cells showed much higher Matrigel invasion capability than the parental cells. They also showed alterations in their adhesion properties to three cell surface proteins. Comparison of metastatic and nonmetastatic cells revealed several significant alterations in the expression of metastasis‐related genes, including up‐regulation of the urokinase‐type plasminogen activator receptor, integrin β1, membrane type 1‐matrix metalloproteinase, and down‐regulation of protease‐activated receptor‐1.

CONCLUSONS

To the authors' knowledge, the current study is the first to report on gene expression analysis using a lymph node metastatic mouse model of human oral SCC. The data suggest that certain alterations of metastasis‐related gene expression favor invasion of oral SCC and that cell surface proteins may play major roles in the metastasis of oral SCC to the lymph nodes. Cancer 2002;95:1663–72. © 2002 American Cancer Society.

DOI 10.1002/cncr.10837