bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of Amide Proton Exchange Mass Spectrometry for the Study of Protein‐Protein Interactions
Authors: Mandell Jeffrey G. , Baerga‐Ortiz Abel , Croy Carrie H. , Falick Arnold M. , Komives Elizabeth A. 
Published: June 2005

AbstractThis protocol describes amide proton exchange experiments that probe for changes in solvent accessibility at protein‐protein interfaces. The simplest version of the protocol, termed the “on‐exchange” experiment, detects protein‐protein interfaces by taking advantage of the fact that solvent deuterium oxide (D2O) molecules are excluded from the surface of a protein to which another protein is bound. A more complete version of the experiment can also be performed in which the rate of surface deuteration is initially measured separately for each of the proteins involved in the interaction, after which the deuterated proteins are allowed to complex and the rate of “off‐exchange” (i.e., replacement of surface deuterons by protons from solvent H2O molecules) at the resulting protein‐protein interface is measured. This version of the experiment yields additional kinetic information that can help to define the solvent‐inaccessible “core” of the interface.
Improvement of the water selectivity of ULTEM poly(ether imide) pervaporation films by an allylamine‐plasma‐polymerized layer
Authors: Kaba M. , Raklaoui N. , Guimon M.‐F. , Mas A. 
Published: June 2005

AbstractThe wettability and surface energy of extruded ULTEM poly(ether imide) films strongly increased (the water contact angle varied from 75 to 38° and the surface energy varied from 45.3 to 59.5 mJ m−2, respectively) with the deposition of an allylamine‐plasma‐polymerized layer and were characterized with X‐ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy according to the experimental parameters. Pervaporation tests for dehydrating the water/ethanol azeotropic mixture were performed at 40°C with nontreated and plasma‐treated ULTEM films for 15, 30, 60, and 120 min. No significant difference was noticed in the total flow (ca. 2.5 g/m2 h) among the various films. However, for the 30‐min duration, a great increase in the water selectivity from 850 to 10,850 was measured, and it was related to the higher N/C ratio and the presence of amide groups on the surface. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2088–2096, 2005
Plasma induced grafting of PSt onto titanium dioxide powder. II
Authors: Zhong Shaofeng , Meng Yuedong , Ou Qiongrong , Shu Xingsheng 
Published: June 2005

AbstractGrafting of polystyrene (PSt) onto titanium dioxide powder was investigated in this study. The graft polymerization reaction was induced by N2 plasma treatment of the surfaces of the titanium dioxide powder. IR and XPS results showed that PSt was grafted onto the titanium dioxide powder. The crystal structure of the titanium dioxide powder observed by XRD spectra was unchanged after plasma graft polymerization. In the grafting reaction, the grafting yield increased with the plasma power, the plasma treatment time, and the grafting reaction, but it increased first then decreased after reaching 50°C. The type of monomers also has an effect on the grafting yield. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2112–2117, 2005
Melt spinning of poly(L‐lactic acid) and its biodegradability
Authors: Nishimura Yoshiro , Takasu Akinori , Inai Yoshihito , Hirabayashi Tadamichi 
Published: June 2005

AbstractThe melt spinning and melt drawing of poly(L‐lactic acid) (PLLA) were carried out with a melt‐spinning machine, and the mechanical properties, structure, and biodegradability of PLLA fiber were investigated. PLLA fiber with a tensile strength of 0.81 GPa was successfully obtained through two steps of drawing at a draw ratio of 18 in hot water. This fiber had enough tensile strength for common engineering use. The fiber could be degraded under controlled composting conditions at 70°C for 1 week. In scanning electron microscopy observations of the fiber, a regular pattern of cracks running along the vertical direction to the fiber axis was clearly observed. This suggested that the PLLA fiber built up a highly ordered structure arranged along the direction of the fiber axis. After the fiber was left to lie in the ground for 1 year, however, the surface of the fiber was still smooth, and the tensile strength did not decrease much. This PLLA fiber could not be hydrolyzed after 1 month of steeping in a buffer solution at 37°C, but it was rapidly hydrolyzed at more than 60°C. It was suggested that the degradation (hydrolysis) rate of PLLA depended on the glass‐transition temperature. Upon hydrolysis at 80°C for 48 h, a regular crack along the vertical direction to the fiber axis was found that was very similar to that observed in degradation under composting conditions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2118–2124, 2005
Viscoelastic characterization of uncured NR/Cel II compositions
Authors: Martins Agnes F. , Visconte Leila L. Y. , Nunes Regina C. R. 
Published: June 2005

AbstractIn this work three types of equipments were used, namely, rubber process analyzer (RPA 2000), Mooney viscometer, and dynamic mechanical thermal analyzer, to characterize natural rubber mixtures containing different amounts of regenerated celulose (Cel II) as filler. The RPA 2000 is a new dynamic rheological tester that can analyze raw polymers and masterbatches as well as rubber compounds before, during, and after cure. The Mooney viscometer is probably the most widely used method for measuring shearing viscosity of unvulcanized rubbers or rubber compositions. DMTA is used to assess filler–rubber interactions. In the present investigation, RPA tests on unvulcanized natural rubber and regenerated cellulose (Cel II) mixtures were carried out using strain and frequency sweeps, and the Mooney viscosities were determined using the relaxation accessory and the small rotor. DMTA data were taken at a fixed frequency and temperature sweep. The filler content was increased up to 30 phr. Compositions were prepared by cocoagulation of natural latex and cellulose xanthate mixtures. The results showed a good dispersion of the filler in the rubber matrix and its large influence on rheological and dynamic properties of the resulting compositions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2125–2131, 2005
Hydroxylation of pendant vinyl groups of poly(3‐hydroxy undec‐10‐enoate) in high yield
Authors: Eroğlu Mehmet S. , Hazer Baki , Ozturk Turan , Caykara Tuncer 
Published: June 2005

AbstractPoly(3‐hydroxy undec‐10‐enoate) (PHU) was synthesized by feeding Pseudomonas oleovarans with 10‐undecenoic acid and nearly 100% hydroxylation of double bonds of PHU was achieved by hydroboration–oxidation reaction using 9‐borobicyclononane. The disappearance of vinyl signals of PHU in proton and 13C NMR spectra was observed. Acetylation of hydroxylated PHU was conducted for molecular weight measurements. Molecular weight and polydispersity of hydroxylated PHU were found to be 10,000 and 1.23, respectively, while that of the originals was 32,000 and 2.42. Decomposition temperatures of original and hydroxylated PHU were 280 and 200°C, respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2132–2139, 2005
Effect of layering pattern on dynamic mechanical properties of randomly oriented short banana/sisal hybrid fiber–reinforced polyester composites
Authors: Idicula Maries , Malhotra S. K. , Joseph Kuruvilla , Thomas Sabu 
Published: June 2005

AbstractDynamic mechanical test methods have been widely employed for investigating the structures and viscoelastic behavior of polymeric materials to determine their relevant stiffness and damping characteristics for various applications. Randomly oriented short banana/sisal hybrid fiber–reinforced polyester composites were prepared by keeping the volume ratio of banana and sisal 1 : 1 and the total fiber loading 0.40 volume fraction. Bilayer (banana/sisal), trilayer (banana/sisal/banana and sisal/banana/sisal), and intimate mix composites were prepared. The effect of layering pattern on storage modulus (E′), damping behavior (tan δ), and loss modulus (E″) was studied as a function of temperature and frequency. Bilayer composite showed high damping property while intimately mixed and banana/sisal/banana composites showed increased stiffness compared to the other pattern. The Arrhenius relationship has been used to calculate the activation energy of the glass transition of the composites. The activation energy of the intimately mixed composite was found to be the highest. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2168–2174, 2005
The mechanism and technology parameters optimization of alkali‐H2O2 one‐bath cooking and bleaching of hemp
Authors: Qu Li‐Jun , Zhu Shi‐Feng , Liu Ming‐Jun , Wang Shan‐Yuan 
Published: June 2005

AbstractHemp is cooked and bleached in alkali‐H2O2 one‐bath. The analysis of physical and chemical properties related to acid, alkali, and hydrogen peroxide about various types of components in hemp such as hemicelluloses and pectin, and lignin components makes it ascertained. In this one‐bath process, alkali and H2O2 have cooperative effects to remove most proportions of the noncellulosic components efficiently. The additive MgSO4 and a stabilizer of H2O2 as auxiliary agents are introduced to protect cellulose from degradation and, meanwhile, they improve the efficiency of H2O2. The universal rotatable composite experiment design is employed to get the highly precise equation, in which the variables of NaOH and H2O2 concentrations, and the processing time are considered to be the main technological parameters of this alkali‐H2O2 one‐bath process. The residual gum content and residual lignin content of hemp fiber are the evaluation indexes. Based on regression equations, the figures are plotted to analyze the influences of parameters on the evaluation indexes; the optimization multicriteria mathematical model is simultaneously established to obtain the optimum parameters. Finally, an experiment is carried out to further test the acceptance of the calculated optimum values. It is shown that, for the hemp taken from Anhui Province of China, this alkali‐H2O2 one‐bath process can substantially remove gum and lignin from raw hemp. NaOH 10.5 g/L, H2O2 9.8 g/L, and the processing time of 127 min with 0.1% MgSO4 + 2.7 g/L stabilizer of H2O2 at 100°C are recommended to be the optimum parameters; then, a compromise is achieved among the lowest lignin content, the residual gum content, and the best strength and whiteness of hemp fiber. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2279–2285, 2005
Compliant phase reduces polymerization shrinkage in dental composite resin
Authors: Lee Valerie A. , Rawls H. Ralph 
Published: June 2005

AbstractCommercially available dental composite resins undergo polymerization shrinkage during curing, setting up internal stress that can result in debonding at the tooth‐composite interface, tooth fracture and composite failure. Debonding can also lead to marginal leakage and recurrent decay. The presence of a compliant phase, in this case polybutadiene in aggregate form with fumed silica, is shown to reduce polymerization shrinkage in the bis‐GMA/TEGDMA resin system. The addition of a small amount of the plasticizer triphenylethylene promoted additional reduction in cure shrinkage by reducing the glass transition temperature, Tg. A trend toward reduced cure shrinkage was noted as the polybutadiene : silica ratio decreased within each molecular weight of polybutadiene tested. The optimal formulation tested was determined to be 0.25 wt. % triphenylethylene in bis‐GMA with aggregates formed from polybutadiene of molecular weight 2–3 million, in a polybutadiene : silica ratio of 0.005. Shrinkage reduction in this system was ∼ 42% without loss of Knoop hardness. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2306–2310, 2005
Characterization of the 5′ regulatory region of the Drosophila Dmdop1 dopamine receptor‐gene
Authors: Kehren Verena , Baumann Arnd 
Published: June 2005

AbstractThe pharmacological and functional properties of many biogenic‐amine receptors have been thoroughly investigated. In contrast, knowledge about the transcriptional regulation of receptor genes is limited. Here we describe the structural and functional properties of the promoter region of a dopamine receptor‐gene (Dmdop1) from Drosophila. The transcriptional start site was identified by 5′‐RACE (5′‐rapid amplification of cDNA ends) cloning and primer‐extension analysis. A consensus site for transcriptional initiation (INR element) is located 494 bp upstream of the ATG codon of the open reading‐frame. The promoter neither contains TATA‐ nor CAAT boxes but several GC‐rich elements. Relative promoter activity was monitored by CAT reporter‐gene analysis in different neuronal cell lines. The Dmdop1 promoter contains one activating (–454/+125) and two silencing regions (–1481/–454 and +125/+495). Interestingly, one silencing region harbours a CRE (cAMP responsive element) site. Since the DmDOP1 receptor leads to cAMP production in cells, the CRE site might contribute to the receptors' own expression by cAMP‐dependent transcription factors. Arch. Insect Biochem. Physiol. 59:118–131, 2005. © 2005 Wiley‐Liss, Inc.
Molecular biology of the invertebrate dopamine receptors
Authors: Mustard Julie A. , Beggs Kyle T. , Mercer Alison R. 
Published: June 2005

AbstractDopamine is found in the nervous systems of both vertebrates and invertebrates. However, the specific actions of dopamine depend on the dopamine receptor type that is expressed in the target cell. As in mammals, different subtypes of dopamine receptors have been cloned and characterized from invertebrates, and these receptor subtypes have different structural and functional properties. Understanding how these receptors respond to dopamine and in which cells each receptor type is expressed is key to our understanding of the role of dopamine signaling. Comparison of the amino acid sequences and experimentally determined functional properties suggest that there are at least three distinct types of dopamine receptors in invertebrates. This review focuses on invertebrate dopamine receptors for which the genes have been isolated and identified, and examines our current knowledge of the functional and structural properties of these receptors, and their pharmacology and expression. Arch. Insect Biochem. Physiol. 59:103–117, 2005. © 2005 Wiley‐Liss, Inc.
Prevalence of and risk factors for low bone mineral density and vertebral fractures in patients with systemic lupus erythematosus
Authors: Bultink Irene E. M. , Lems Willem F. , Kostense Piet J. , Dijkmans Ben A. C. , Voskuyl Alexandre E. 
Published: June 2005

AbstractObjectiveTo examine the prevalence of and risk factors for low bone mineral density (BMD) and vertebral fractures in patients with systemic lupus erythematosus (SLE).MethodsWe studied 107 SLE patients. Demographic and clinical data were collected, and radiographs of the thoracic and lumbar spine and BMD measurements by dual x‐ray absorptiometry were performed. Vertebral deformities were scored according to the method of Genant et al: fractures were defined as a reduction of ≥20% of the vertebral body height. Osteoporosis was defined as a T score less than −2.5 SD and osteopenia as a T score less than −1.0 SD in at least 1 region of measurement.ResultsOsteopenia was present in 39% of the patients and osteoporosis in 4% (93% female; mean age 41.1 years). In multiple regression analysis, low BMD in the spine was associated with a low body mass index (BMI), postmenopausal status, and 25‐hydroxyvitamin D deficiency. Low BMD in the hip was associated with low BMI and postmenopausal status. At least 1 vertebral fracture was detected in 20% of the patients. Vertebral fractures were associated with ever use of intravenous methylprednisolone and male sex.ConclusionRisk factors for low BMD in SLE patients are low BMI, postmenopausal status, and vitamin D deficiency. While osteoporosis defined as a low T score was found in only 4% of the patients, osteoporotic vertebral fractures were detected in 20%. The high prevalence of low BMD and vertebral fractures implies that more attention must be paid to the prevention and treatment of osteoporosis and fractures in SLE.
Frequency of osteopenia in children and young adults with childhood‐onset systemic lupus erythematosus
Authors: Lilleby Vibke , Lien Gunhild , Frey Frøslie Kathrine , Haugen Margaretha , Flatø Berit , Førre ØYstein 
Published: June 2005

AbstractObjectiveTo determine the frequency of osteopenia in patients with childhood‐onset systemic lupus erythematosus (SLE) compared with that in healthy matched controls, and to evaluate the relationship between disease‐related variables and bone mineral mass.MethodsBone mineral density (BMD) and bone mineral content (BMC) were measured in a cohort of 70 patients with childhood‐onset SLE (mean ± SD disease duration 10.8 ± 8.3 years, mean ± SD age 26.4 ± 9.9 years) and 70 age‐ and sex‐matched healthy controls. BMD and BMC of the femoral neck, lumbar spine, total body, and distal one‐third of the radius were measured by dual x‐ray absorptiometry. We investigated the relationship between BMC and the following disease variables: cumulative dose of corticosteroids, organ damage, current use of corticosteroids, use of cyclophosphamide, age at disease onset, and disease activity at the time of diagnosis. Biochemical markers of bone metabolism were also measured.ResultsBMD values for the lumbar spine and femoral neck were significantly lower in patients than in healthy controls. The reduction in BMD of the lumbar spine was significantly greater than that of the total body. In multiple linear regression analyses, a higher cumulative corticosteroid dose was significantly associated with lower BMC of the lumbar spine and femoral neck. Decreased lumbar spine BMC was also related to male sex.ConclusionThe frequency of osteopenia was higher in patients with childhood‐onset SLE than in matched controls. The lumbar spine was the most seriously affected skeletal site, followed by the femoral neck. The cumulative dose of corticosteroids was shown to be an important explanatory variable for BMC values in the lumbar spine and femoral neck.
Dysregulation of chemokine receptor expression and function by B cells of patients with primary Sjögren's syndrome
Authors: Hansen Arne , Reiter Karin , Ziprian Till , Jacobi Annett , Hoffmann Andreas , Gosemann Mirko , Scholze Jürgen , Lipsky Peter E. , Dörner Thomas 
Published: June 2005

AbstractObjectiveTo assess whether abnormal chemokine receptor expression and/or abnormal responsiveness to the cognate ligands might underlie some of the disturbances in B cell homeostasis characteristic of primary Sjögren's syndrome (SS).MethodsChemokine receptor expression by CD27− naive and CD27+ memory B cells from patients with primary SS and healthy control subjects was analyzed using flow cytometry, single‐cell reverse transcriptase–polymerase chain reaction (RT‐PCR), and migration assays.ResultsIn contrast to healthy subjects, significantly higher expression of both surface CXCR4 and CXCR4 messenger RNA (mRNA) was seen in peripheral blood B cells from patients with primary SS. These differences were most prominent in CD27− naive B cells (P ≤ 0.0006). In addition, significantly higher frequencies of CD27− naive B cells from patients with primary SS expressed mRNA for the inhibitory regulator of G protein signaling 13 (P = 0.001). Expression of CXCR5 by peripheral CD27+ memory B cells was moderately diminished in patients with primary SS compared with healthy controls (P = 0.038). No significant differences were noted in the expression of CXCR3, CCR6, CCR7, and CCR9 between B cells from healthy controls and those from patients with primary SS. Transmigration assays of blood B cells from patients with primary SS and healthy controls showed comparable responses of CD27− naive B cells but significantly diminished responses of activated primary SS CD27+ memory B cells to the ligands of CXCR4 and CXCR5, CXCL12 (P = 0.032), and CXCL13 (B lymphocyte chemoattractant; B cell–attracting chemokine 1; P = 0.018), respectively, when compared with those from healthy controls. Finally, compared with controls, peripheral reduction but glandular accumulation of CXCR4+,CXCR5+,CD27+ memory B cells was identified in patients with primary SS.ConclusionIn primary SS, overexpression of CXCR4 by circulating blood B cells does not translate into enhanced migratory response to the cognate ligand, CXCL12. This migratory response may be modulated by intracellular regulators. Retention of CXCR4+,CXCR5+, CD27+ memory B cells in the inflamed glands seems to contribute to diminished peripheral CD27+ memory B cells in primary SS.
Weight loss reduces knee‐joint loads in overweight and obese older adults with knee osteoarthritis
Authors: Messier Stephen P. , Gutekunst David J. , Davis Cralen , DeVita Paul 
Published: June 2005

AbstractObjectiveTo determine the relationship between change in body mass and knee‐joint moments and forces during walking in overweight and obese older adults with knee osteoarthritis (OA) following an 18‐month clinical trial of diet and exercise.MethodsData were obtained from 142 sedentary, overweight, and obese older adults with self‐reported disability and radiographic evidence of knee OA who underwent 3‐dimensional gait analysis. Gait kinetic outcome variables included peak knee‐joint forces and peak internal knee‐joint moments. Mixed regression models were created to predict followup kinetic values, using followup body mass as the primary explanatory variable. Baseline body mass was used as a covariate, and thus followup body mass was a surrogate measure for change in body mass (i.e., weight loss).ResultsThere was a significant direct association between followup body mass and peak followup values of compressive force (P = 0.001), resultant force (P = 0.002), abduction moment (P = 0.03), and medial rotation moment (P = 0.02). A weight reduction of 9.8N (1 kg) was associated with reductions of 40.6N and 38.7N in compressive and resultant forces, respectively. Thus, each weight‐loss unit was associated with an ∼4‐unit reduction in knee‐joint forces. In addition, a reduction in body weight of 9.8N (1 kg) was associated with a 1.4% reduction (0.496 Nm) in knee abduction moment.ConclusionOur results indicate that each pound of weight lost will result in a 4‐fold reduction in the load exerted on the knee per step during daily activities. Accumulated over thousands of steps per day, a reduction of this magnitude would appear to be clinically meaningful.