bluuebunny/crossref_metadata_2025 huggingface dataset:
High Levels of Human Antigen-Specific CD4+ T Cells in Peripheral Blood Revealed by Stimulated Coexpression of CD25 and CD134 (OX40)
Authors: Zaunders John J. , Munier Mee Ling , Seddiki Nabila , Pett Sarah , Ip Susanna , Bailey Michelle , Xu Yin , Brown Kai , Dyer Wayne B. , Kim Min , de Rose Robert , Kent Stephen J. , Jiang Lele , Breit Samuel N. , Emery Sean , Cunningham Anthony L. , Cooper David A. , Kelleher Anthony D.
Published: July 2009

Ag-specific human CD4+ memory T lymphocytes have mostly been studied using assays of proliferation in vitro. Intracellular cytokine and ELISPOT assays quantify effector cell populations but barely detect responses to certain recall Ags that elicit strong proliferative responses, e.g., tetanus toxoid, that comprise non-Th1 CD4+ cells. We have found that culturing whole blood with Ag for 40–48 h induces specific CD4+ T cells to simultaneously express CD25 and CD134. This new technique readily detects responses to well-described CD4+ T cell recall Ags, including preparations of mycobacteria, CMV, HSV-1, influenza, tetanus toxoid, Candida albicans, and streptokinase, as well as HIV-1 peptides, with high specificity. The assay detects much higher levels of Ag-specific cells than intracellular cytokine assays, plus the cells retain viability and can be sorted for in vitro expansion. Furthermore, current in vitro assays for human CD4+ memory T lymphocytes are too labor-intensive and difficult to standardize for routine diagnostic laboratories, whereas the whole-blood CD25+CD134+ assay combines simplicity of setup with a straightforward cell surface flow cytometry readout. In addition to revealing the true extent of Ag-specific human CD4+ memory T lymphocytes, its greatest use will be as a simple in vitro monitor of CD4+ T cell responses to Ags such as tuberculosis infection or vaccines.
TLR4-Mediated Signaling Induces MMP9-Dependent Cleavage of B Cell Surface CD23
Authors: Jackson Leila , Cady Carol T. , Cambier John C.
Published: July 2009

IgE production is inversely regulated by circulating and B cell surface levels of the low affinity IgE receptor, CD23. To begin to understand physiologic determinants of CD23 expression, we analyzed effects of BCR and TLR stimulation on CD23 levels. BCR and TLR 2, 3, 4, 6, and 9 agonists induced CD23 down-modulation from the cell surface. However, among the ligands only TLR4 agonists induced transcriptional activation of CD23 and generation of significant soluble CD23. These responses were induced by LPS both in vitro and in vivo, and were seen in both murine and human B cells. LPS also induced expression of matrix metalloprotease 9 (MMP9) and failed to induce CD23 cleaving activity in MMP9−/− cells, thus implicating MMP9 in the LPS-induced release of CD23 from the cell surface. Finally, type 1 transitional B cells uniquely produce MMP9 in response to LPS, suggesting a mechanism wherein endotoxin induces T1 cell expression of MMP9, which mediates cleavage of CD23 on distinct, mature B cells.
P2X1 Ion Channels Promote Neutrophil Chemotaxis through Rho Kinase Activation
Authors: Lecut Christelle , Frederix Kim , Johnson Daniel M. , Deroanne Christophe , Thiry Marc , Faccinetto Céline , Marée Raphaël , Evans Richard J. , Volders Paul G. A. , Bours Vincent , Oury Cécile
Published: July 2009

ATP, released at the leading edge of migrating neutrophils, amplifies chemotactic signals. The aim of our study was to investigate whether neutrophils express ATP-gated P2X1 ion channels and whether these channels could play a role in chemotaxis. Whole-cell patch clamp experiments showed rapidly desensitizing currents in both human and mouse neutrophils stimulated with P2X1 agonists, αβ-methylene ATP (αβMeATP) and βγMeATP. These currents were strongly impaired or absent in neutrophils from P2X1−/− mice. In Boyden chamber assays, αβMeATP provoked chemokinesis and enhanced formylated peptide- and IL-8-induced chemotaxis of human neutrophils. This agonist similarly increased W-peptide-induced chemotaxis of wild-type mouse neutrophils, whereas it had no effect on P2X1−/− neutrophils. In human as in mouse neutrophils, αβMeATP selectively activated the small RhoGTPase RhoA that caused reversible myosin L chain phosphorylation. Moreover, the αβMeATP-elicited neutrophil movements were prevented by the two Rho kinase inhibitors, Y27632 and H1152. In a gradient of W-peptide, P2X1−/− neutrophils migrated with reduced speed and displayed impaired trailing edge retraction. Finally, neutrophil recruitment in mouse peritoneum upon Escherichia coli injection was enhanced in wild-type mice treated with αβMeATP, whereas it was significantly impaired in the P2X1−/− mice. Thus, activation of P2X1 ion channels by ATP promotes neutrophil chemotaxis, a process involving Rho kinase-dependent actomyosin-mediated contraction at the cell rear. These ion channels may therefore play a significant role in host defense and inflammation.
E-Prostanoid 3 Receptor Deletion Improves Pulmonary Host Defense and Protects Mice from Death in SevereStreptococcus pneumoniaeInfection
Authors: Aronoff David M. , Lewis Casey , Serezani Carlos H. , Eaton Kathryn A. , Goel Deepti , Phipps John C. , Peters-Golden Marc , Mancuso Peter
Published: July 2009

Prostaglandins (PGs) are potent lipid mediators that are produced during infections and whose synthesis and signaling networks present potential pharmacologic targets for immunomodulation. PGE2 acts through the ligation of four distinct G protein-coupled receptors, E-prostanoid (EP) 1–4. Previous in vitro and in vivo studies demonstrated that the activation of the Gαs-coupled EP2 and EP4 receptors suppresses inflammatory responses to microbial pathogens through cAMP-dependent signaling cascades. Although it is speculated that PGE2 signaling via the Gαi-coupled EP3 receptor might counteract EP2/EP4 immunosuppression in the context of bacterial infection (or severe inflammation), this has not previously been tested in vivo. To address this, we infected wild-type (EP3+/+) and EP3−/− mice with the important respiratory pathogen Streptococcus pneumoniae or injected mice i.p. with LPS. Unexpectedly, we observed that EP3−/− mice were protected from mortality after infection or LPS. The enhanced survival observed in the infected EP3−/− mice correlated with enhanced pulmonary clearance of bacteria; reduced accumulation of lung neutrophils; lower numbers of circulating blood leukocytes; and an impaired febrile response to infection. In vitro studies revealed improved alveolar macrophage phagocytic and bactericidal capacities in EP3−/− cells that were associated with an increased capacity to generate NO in response to immune stimulation. Our studies underscore the complex nature of PGE2 immunomodulation in the context of host-microbial interactions in the lung. Pharmacological targeting of the PGE2-EP3 axis represents a novel area warranting greater investigative interest in the prevention and/or treatment of infectious diseases.
Transgenic Expression of Single-Chain Anti-CTLA-4 Fv on β Cells Protects Nonobese Diabetic Mice from Autoimmune Diabetes
Authors: Shieh Shing-Jia , Chou Feng-Cheng , Yu Pei-Ning , Lin Wen-Chi , Chang Deh-Ming , Roffler Steve R. , Sytwu Huey-Kang
Published: July 2009

T cell-mediated immunodestruction of pancreatic β cells is the key process responsible for both the development of autoimmune diabetes and the induction of rejection during islet transplantation. In this study, we investigate the hypothesis that transgenic expression of an agonistic, membrane-bound single-chain anti-CTLA-4 Fv (anti-CTLA-4 scFv) on pancreatic β cells can inhibit autoimmune processes by selectively targeting CTLA-4 on pathogenic T cells. Strikingly, transgenic expression of anti-CTLA-4 scFv on pancreatic β cells significantly protected NOD mice from spontaneous autoimmune diabetes. Interestingly, local expression of this CTLA-4 agonist did not alter the diabetogenic properties of systemic lymphocytes, because splenocytes from transgenic mice or their nontransgenic littermates equally transferred diabetes in NOD/SCID recipients. By analyzing the T cell development in anti-CTLA-4 scFv/Th1/Th2 triple transgenic mice, we found that β cell-specific expression of CTLA-4 agonist did not affect the development of Th1/Th2 or CD4+CD25+ regulatory T cells. Most strikingly, islets from transgenic mice inhibited T cell response to immobilized anti-CD3 in a T cell-islet coculture system, suggesting a trans-mediated inhibition provided by transgenic islets. Finally, transgenic islets implanted in diabetic recipients survived much longer than did wild-type islets, indicating a therapeutic potential of this genetically modified islet graft in autoimmune diabetes.
Epitaxial Growth of Highly Oriented Fibers of Semiconducting Polymers with a Shish‐Kebab‐Like Superstructure
Authors: Brinkmann Martin , Chandezon Frédéric , Pansu Robert B. , Julien‐Rabant Carine
Published: July 2009

Highly oriented fibers of regioregular poly(3‐alkylthiophene)s (P3ATs) showing a “shish‐kebab” morphology are prepared by oriented epitaxial crystallization in a mixture of 1,3,5‐trichlorobenzene (TCB) and pyridine. The superstructure of the P3AT fibers consists of an oriented thread‐like core several hundreds of micrometers long, the “shish”, onto which lateral crystalline fibrils made of folded polymer chains, the “kebabs”, are connected in a periodic way with a periodicity in the range 18–30 nm. The P3AT‐chain axis is oriented parallel to the fiber axis whereas the π‐stacking direction is oriented perpendicular to it. The oriented character of the shish‐kebab fibers results in polarized optical absorption and photoluminescence. The formation of oriented precursors by epitaxial orientation of polymer chains onto long needles of a molecular crystal—TCB in the present case—appears to be an original alternative to the crystallization usually performed under external flow conditions.
A projection‐based method for production planning of multiproduct facilities
Authors: Sung Charles , Maravelias Christos T.
Published: July 2009

An algorithm is presented for identifying the projection of a scheduling model's feasible region onto the space of production targets. The projected feasible region is expressed using one of two mixed‐integer programming formulations, which can be readily used to address integrated production planning and scheduling problems that were previously intractable. Production planning is solved in combination with a surrogate model representing the region of feasible production amounts to provide optimum production targets, while a detailed scheduling is solved in a rolling‐horizon manner to define feasible schedules for meeting these targets. The proposed framework provides solutions of higher quality and yields tighter bounds than previously proposed approaches. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Migration and sedimentation of spherical particles in a yield stress fluid flowing in a horizontal cylindrical pipe
Authors: Merkak Othmane , Jossic Laurent , Magnin Albert
Published: July 2009

This study looks at the dynamics of a particle suspended in a viscoplastic fluid, flowing in a horizontal circular cylindrical pipe. Inertia effects are negligible in comparison with viscous effects and plastic effects. The suspensions are highly stabilized and at rest the spheres cannot settle under gravity alone. The results of Merkak et al. (AIChE J. 2008;54:1129–1138) are extended, taking into consideration both particles of the same density or denser than the fluid and pipe‐to‐particle diameter ratios of 8 or 56. New migration phenomena in the sheared zone are thus evidenced when buoyancy forces are nil. In the case of particles denser than the fluid, it is shown how the spheres settle by bypassing the plug‐flow zone. A map showing the stability of flowing suspensions could, thus, be drawn. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Genetic composition of Brazilian population samples based on a set of twenty‐eight ancestry informative SNPs
Authors: Lins Tulio C. , Vieira Rodrigo G. , Abreu Breno S. , Grattapaglia Dario , Pereira Rinaldo W.
Published: July 2009

Ancestry informative SNPs can be useful to estimate individual and population biogeographical ancestry. Brazilian population is characterized by a genetic background of three parental populations (European, African, and Brazilian Native Amerindians) with a wide degree and diverse patterns of admixture. In this work we analyzed the information content of 28 ancestry‐informative SNPs into multiplexed panels using three parental population sources (African, Amerindian, and European) to infer the genetic admixture in an urban sample of the five Brazilian geopolitical regions. The SNPs assigned apart the parental populations from each other and thus can be applied for ancestry estimation in a three hybrid admixed population. Data was used to infer genetic ancestry in Brazilians with an admixture model. Pairwise estimates of Fst among the five Brazilian geopolitical regions suggested little genetic differentiation only between the South and the remaining regions. Estimates of ancestry results are consistent with the heterogeneous genetic profile of Brazilian population, with a major contribution of European ancestry (0.771) followed by African (0.143) and Amerindian contributions (0.085). The described multiplexed SNP panels can be useful tool for bioanthropological studies but it can be mainly valuable to control for spurious results in genetic association studies in admixed populations. Am. J. Hum. Biol., 2010. © 2009 Wiley‐Liss, Inc.
Development of microsatellite DNA markers and their chromosome assignment in the common marmoset
Authors: Katoh Hideki , Takabayashi Shuji , Itoh Toshio
Published: July 2009

This study was performed to develop microsatellite DNA markers, which are useful for linkage analyses, gene mapping and blood chimera analyses in the common marmoset (Callithrix jacchus). We searched 153 of 295 bacterial artificial clone DNA sequences of the common marmoset that were archived in the NCBI database in 2004. On the basis of the search, we designed 186 PCR primer sets. When tested using 5 unrelated individuals, we successfully detected 154 markers with PCR products, of which 80 (52%) were polymorphic and 74 (48%) were monomorphic. We assigned each of the 154 markers to a human chromosome based on BLAST searches, which was achieved by searching the entire human genome sequences using an ∼3 kb section of each forward primer sequence, including ∼1.5 kb of the upstream and ∼1.5 kb of the downstream sequences. Combining our assignment data and the chromosome painting‐assisted karyotype of the common marmoset [Sherlock et al., Genomics 33:214–219, 1996], we prepared a list of 154 microsatellite DNA markers that were assigned to human chromosomes, except for the Y chromosome, which is equivalent to a chromosome map. Using five microsatellite DNA markers, we have established a fragment analysis method with a sequencer, which can be routinely used for blood chimera analysis, parentage diagnosis and individual identification. Am. J. Primatol. 71:912–918, 2009. © 2009 Wiley‐Liss, Inc.
Technical note: Applicability of tooth cementum annulation to an archaeological population
Authors: Roksandic Mirjana , Vlak Dejana , Schillaci Michael A. , Voicu Diana
Published: July 2009

The use of tooth cementum annulations for age determination has been deemed promising, exhibiting high correlations with chronological age. Despite its apparent potential, to date, the tooth cementum annulations method has been used rarely for estimating ages in archaeological populations. Here we examine the readability of cementum annulations and the consistency of age estimates using a sample of 116 adults from the Iron Gates Gorge Mesolithic/Neolithic series. Our examination of the method pointed to several sources of error that call into question the use of this method for estimating the chronological ages of archaeologically derived dental samples. The poor performance of the method in our analysis might be explained by taphonomic influences, including the effect of chemical and biological agents on dental microstructures. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.
The interplay between speed, kinetics, and hand postures during primate terrestrial locomotion
Authors: Patel Biren A.
Published: July 2009

Nonprimate terrestrial mammals may use digitigrade postures to help moderate distal limb joint moments and metapodial stresses that may arise during high‐speed locomotion with high‐ground reaction forces (GRF). This study evaluates the relationships between speed, GRFs, and distal forelimb kinematics in order to evaluate if primates also adopt digitigrade hand postures during terrestrial locomotion for these same reasons. Three cercopithecine monkey species (Papio anubis, Macaca mulatta, Erythrocebus patas) were videotaped moving unrestrained along a horizontal runway instrumented with a force platform. Three‐dimensional forelimb kinematics and GRFs were measured when the vertical force component reached its peak. Hand posture was measured as the angle between the metacarpal segment and the ground (MGA). As predicted, digitigrade hand postures (larger MGA) are associated with shorter GRF moment arms and lower wrist joint moments. Contrary to expectations, individuals used more palmigrade‐like (i.e. less digitigrade) hand postures (smaller MGA) when the forelimb was subjected to higher forces (at faster speeds) resulting in potentially larger wrist joint moments. Accordingly, these primates may not use their ability to alter their hand postures to reduce rising joint moments at faster speeds. Digitigrady at slow speeds may improve the mechanical advantage of antigravity muscles crossing the wrist joint. At faster speeds, greater palmigrady is likely caused by joint collapse, but this posture may be suited to distribute higher GRFs over a larger surface area to lower stresses throughout the hand. Thus, a digitigrade hand posture is not a cursorial (i.e. high speed) adaptation in primates and differs from that of other mammals. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.
Chitosan‐magnetite nanocomposites for effective removal of urea in “magnetic hemodialysis therapy”: A novel concept
Authors: Pathak Abhishek , Bajpai Sunil K.
Published: July 2009

The present study explores the possibilities of using chitosan‐magnetite (CM) nanocomposites for removal of urea in blood serum. The CM nanocomposites, with an average diameter in the range of 12–33 nm, were characterized by transmission electron microscopic and selected area electron diffraction analysis. The particles demonstrate fair ability to remove urea in human blood serum. The maximum removal efficiency was nearly 26%, when 200 mg of CM nanocomposites were allowed to agitate with 25 mL of urea solution of concentration 100 mg/dL. The CM nanocomposites could be easily removed by applying moderate magnetic field. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mechanical properties of bioplastics and bioplastic–organoclay nanocomposites prepared from epoxidized soybean oil with different epoxide contents
Authors: Tanrattanakul Varaporn , Saithai Pimchanok
Published: July 2009

The objectives of this study were to investigate the effect of epoxide content (24–88 mol %) on the mechanical properties and characteristics of epoxidized soybean oil (ESO) and to compare the mechanical properties of ESO–organoclay nanocomposites with different epoxide contents (40 and 100 mol %). ESO was synthesized by in situ epoxidation with acetic acid and hydrogen peroxide. We prepared ESO bioplastic sheets from ESO by curing with methyltetrahydrophthalic anhydride and 1‐methylimidazole. The tensile properties and tear resistance of the synthesized bioplastic (ESO40, where the number indicates the molar percentage of epoxidation) were investigated and compared with ESO bioplastic sheets prepared from commercial ESO with 100 mol % epoxidation (ESO100). The tensile modulus, tensile strength, tensile toughness, and tear strength of the ESO bioplastics increased with increasing epoxide content, whereas the elongation at break of the ESO100 bioplastic was lowest. No trend was observed in the bioplastics prepared from ESO24–ESO88. Dynamic mechanical thermal analysis showed increases in the storage modulus and glass‐transition temperature as the epoxide content was increased. Thermal degradation also increased with increasing epoxide content. The crosslink density and chain flexibility controlled the mechanical properties and characteristics of the ESO bioplastics. ESO–organoclay nanocomposites were prepared by in situ intercalative polymerization. The addition of organoclay increased the mechanical properties of the ESO bioplastics. The effect of organoclay content (1–8 wt %) on the mechanical properties was similar to the effect of the epoxide content. The sESO100 nanocomposite showed a higher modulus but lower tensile strength and elongation at break than the ESO40 nanocomposite. Intercalation of the organoclay in the ESO nanocomposites was observed by transmission electron microscopy and X‐ray diffractometry. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Molecular characterization of alkyd/acrylic latexes prepared by miniemulsion polymerization
Authors: Minari Roque J. , Goikoetxea Monika , Beristain Itxaso , Paulis María , Barandiaran María J. , Asua José M.
Published: July 2009

The molecular characterization of alkyd/acrylic hybrid latexes produced by miniemulsion polymerization was characterized in terms of the resin degree of grafting, acrylic degree of grafting, reacted double bonds in the alkyd, gel content, and molecular weight distribution of the sol part. A simple method based on conventional size exclusion chromatography measurements was developed to estimate the fraction of alkyd resin grafted to the acrylic polymer. The method could be applied to completely soluble hybrids and to hybrids containing gel. Also, the limits of the extraction method used in the literature to estimate the fraction of acrylic polymer grafted to the alkyd was investigated; we found that this technique only provided accurate results at high values of the acrylic degree of grafting. The combination of this information with the reacted double bonds of the alkyd (determined by iodine titration) and the molecular weight distribution of the sol polymer provided a detailed characterization of the alkyd–acrylic hybrid polymer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis, characterization, and properties of ε‐caprolactone and carbonate copolymers
Authors: Chen Hui , Yan Guo‐Ping , Li Liang , Ai Chao‐Wu , Yu Xiang‐Hua
Published: July 2009

A series of copolymers were synthesized by the ring‐opening bulk polymerization of ε‐caprolactone (CL) and 2‐phenyl‐5,5‐bis(hydroxymethyl) trimethylene carbonate (PTC) with tin(II) 2‐ethylhexanoate as a catalyst. These copolymers were further reduced with a palladium/carbonate catalyst to obtain partly deprotected copolymers. The two types of copolymers that were obtained were characterized with 1H‐NMR, Fourier transform infrared spectroscopy, UV, gel permeation chromatography, differential scanning calorimetry, and automatic contact‐angle measurements. The influences of the monomer feed molar ratio, catalyst concentration, and reaction time as well as the reaction temperature on the copolymerization process were also studied. The copolymerization of CL and PTC monomers was a nonideal copolymerization, and the copolymerization reactivity ratio of CL was higher than that of PTC in the polymerization process. In vitro degradation tests indicated that the partly deprotected copolymers possessed faster degradation rates and greater hydrophilicity than the unreduced copolymers. In vitro release profiles of fluorouracil from the copolymers showed that these two types of copolymers had steady drug‐release rates and good controlled‐release properties. Moreover, the partly deprotected copolymers had faster drug‐release rates than the unreduced copolymers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mixed percolating network and mechanical properties of polypropylene/talc composites
Authors: Frihi D. , Masenelli‐Varlot K. , Vigier G. , Satha H.
Published: July 2009

Injected polypropylene/talc composites were studied to evaluate the conditions leading to the formation of a mixed talc/polymer crystalline lamella percolating network and the influence of such a network on the nanocomposite mechanical properties. The talc was either conventional micrometer‐sized (conventional talc) or submicrometer‐sized particles (μ‐talc). In the case of μ‐talc, several talc fractions were studied, ranging from 3 to 30 wt %. The nanocomposite crystallinity was characterized with differential scanning calorimetry and wide‐angle X‐ray scattering. Talc was found to act as a nucleating agent, and only the α phase was detected. Through quantification on a Wilchinsky diagram, the talc particles were found to lie in the sample plane, the polypropylene crystalline lamellae being orthotropically distributed perpendicularly to the talc particles. The mechanical properties of the composites were tested in different directions by tensile and compression tests. The mechanical behavior of the composites confirmed the microstructural model. For low talc loadings, the composite moduli could not be well fitted by a law of mixtures. The large difference between the observed and predicted moduli was attributed to the formation of a mixed percolating network, including talc particles and polypropylene crystalline lamellae. At high talc loadings, when the mixed percolating network was completely formed, the reinforcement could well be described by parallel coupling, which indicated a classical reinforcement mechanism. Finally, the value of the critical talc fraction, at which the mixed percolating network was formed, was examined as a function of talc. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Electrochemical synthesis and studies of polypyrroles doped by renewable dopant cardanol azophenylsulfonic acid derived from cashew nutshells
Authors: Radhakrishan S. , Rao Chepuri R. K. , Vijayan M.
Published: July 2009

The raw material cardanol, a renewable resource, is industrial waste and a pollutant from the cashew nut industry. Cardanol is a useful starting material for synthesizing a new amphiphilic molecule, cardanol azophenylsulfonic acid (CAPSA). In this study, polypyrroles were electrochemically synthesized with the renewable dopant CAPSA. The polymers were characterized with ultraviolet–visible, Fourier transform infrared, conductivity, impedance, charge–discharge, and cyclic voltammetry analyses. The conductivity of the films doped by CAPSA was in the range of 1.23–3.98 × 10−5 S/cm, and they exhibited moderate specific capacitance values. ©2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mechanical strengths of epoxy resin composites reinforced by calcined pearl shell powders
Authors: Ji Genzhong , Zhu Hongqi , Jiang Xuewen , Qi Chenze , Zhang Xian‐Man
Published: July 2009

A series of epoxy resin (EP) composites were prepared using ground pearl shell powders, which had been calcined at various temperatures. The EP composite containing ∼ 3% weight content of the calcined pearl shell powder had the highest impact strength and the presence of silane agent was found to be essential for the composite formulation. The impact strengths of the resultant EP composites were highly influenced by the specific surface area, surface morphological structure, and chemical composition of the calcined pearl shell powder. The highest mechanical improvement was obtained for the EP composite prepared with the pearl shell powder calcined at 700°C for 3 h. The layered biopolymeric materials were completely degraded for the pearl shell powder calcined at 700°C, resulting in “sponge‐like” or “net‐like” porous calcium carbonate powder. However, the degradation of the layered biopolymeric materials was not complete for the calcinations at lower temperatures (<600°C), while calcium carbonate decomposed to form calcium oxide at higher temperatures (>800°C). The mechanical improvements of the processed EP composites have been discussed along with the chemical compositions and surface microstructures of the incorporated pearl shell powders. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and antioxidant activity evaluation of novel broom and cotton fibers derivatives
Authors: Trombino Sonia , Cassano Roberta , Ferrarelli Teresa , Cilea Alessia , Muzzalupo Rita , Cione Erika , Nevio Picci
Published: July 2009

Novel antioxidant biopolymers composed by broom or cotton fibers, and trans‐ferulic acid, α‐lipoic acid, and α‐tocopherol, were prepared. The acids were directly linked to fibers microfibrils hydroxylic groups using N,N‐dimethylacetamide/lithium chloride (DMAc/LiCl) as solvent with dicyclohexylcarbodiimide (DCC) and N,N‐dimethylaminopyridine (DMAP). Broom or cotton tocopherulate were prepared in the same conditions by using carboxylated fibers. Ester linkages were confirmed by using Fourier transformed infrared spectroscopy; biopolymers substitution degrees (DS) were determined by volumetric analysis. Antioxidant activity in inhibiting lipid peroxidation, in rat‐liver microsomal membranes, induced in vitro by two different sources of free radicals, 2,2′‐azobis (2‐amidinopropane) (AAPH) and tert‐butyl hydroperoxide (tert‐BOOH), was evaluated. Finally, biocompatibility of these biomaterials was also tested by controlling glutathione‐S‐transferase (GST) basal concentrations. Our results strongly suggested that the better derivatives were the ferulate ones. However, all obtained biomaterials, showing excellent antioxidant properties and biocompatibility, could be successfully applied in biomedical and in packaging areas. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of high‐impact polystyrene using a multifunctional cyclic peroxide as the initiator
Authors: Acuña P. , Morales G. , de León R. Díaz
Published: July 2009

This work deals with the synthesis of high‐impact polystyrene (HIPS) using a novel cyclic multifunctional initiator, the diethyl ketone triperoxide (DEKTP), analyzing its effect on the prepolymerization step and its influence over the HIPS final properties. DEKTP showed a low selectivity toward grafting reactions at any of the concentrations of initiator and temperatures evaluated, and when it was used under a temperature ramp (120–130°C, heating rate = 2°C/min), the synthesis of HIPS was possible with an adequate development of morphology and impact strength (i.e., 67 J/m) depending on DEKTP concentration. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of novel pseudo‐Fréchet‐type dendrons and their fluorescent enhancement to Eu3+ ion
Authors: Xu Dongmei , Liu Xiaohong , Chen Haijie , Qian Lili , Zhang Keda
Published: July 2009

Novel pseudo‐Fréchet‐type dendrons with 1,3,5‐triazine structure G1.0(NOT) and G2.0(NOT) were synthesized under mild conditions by cyanuric chloride, β‐naphthol, and 3,5‐dihydroxybenzyl alcohol with the yields of 96.3 and 85.6%. The structure of the dendrons was characterized by elementary analysis, IR spectrum, 1H‐NMR, and FAB‐MS. The dendrons had good thermo stability and solubility. They could partially transfer their absorbed energy to Eu3+ ion in tetrahydrofuran/acetone solutions. When the concentration of G1.0(NOT), G2.0(NOT), and Eu3+ ion was 5 × 10−4 mol/L, G1.0(NOT) could enhance the fluorescent intensity of Eu3+ ion at 613 nm by 4.2‐fold, whereas G2.0(NOT) could enhance the fluorescent intensity of Eu3+ ion at 465 and 613 nm by 18.6‐ and 11.7‐fold, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Objective and subjective assessment of reciprocal peer teaching in medical gross anatomy laboratory
Authors: Bentley Brian S. , Hill Robert V.
Published: July 2009

Reciprocal peer teaching (RPT), wherein students alternate roles as teacher and learner, has been applied in several educational arenas with varying success. Here, we describe the implementation of a reciprocal peer teaching protocol in a human gross anatomy laboratory curriculum. We compared the outcomes of the RPT class with those of previous classes in which RPT was not employed. Objective data (i.e., course grades) show no significant differences in gross anatomy laboratory grades between students in the RPT and non‐RPT classes. To subjectively evaluate the relative success of RPT in the laboratory, we analyzed student opinions obtained through anonymous surveys. These data show that a powerful majority of student respondents felt that RPT was beneficial and should be used in future classes. The greatest disadvantage was unreliable quality of teaching from peers; however, most students still felt that RPT should be continued. Students who felt that they had insufficient hands‐on experience (by virtue of dissecting only half the time) were significantly more likely to recommend abandoning RPT. These results underscore the importance of active student dissection, and suggest that a modified version of the described RPT protocol may satisfy more of the needs of large, diverse student populations. Several hidden benefits of RPT exist for faculty, administration, and students, including reduced need for large numbers of cadavers, attendant reduction in operating costs, and smaller student‐to‐teacher ratios. Anat Sci Educ 2:143–149, 2009. © 2009 American Association of Anatomists.
Data mining emotion in social network communication: Gender differences in MySpace
Authors: Thelwall Mike , Wilkinson David , Uppal Sukhvinder
Published: July 2009

Despite the rapid growth in social network sites and in data mining for emotion (sentiment analysis), little research has tied the two together, and none has had social science goals. This article examines the extent to which emotion is present in MySpace comments, using a combination of data mining and content analysis, and exploring age and gender. A random sample of 819 public comments to or from U.S. users was manually classified for strength of positive and negative emotion. Two thirds of the comments expressed positive emotion, but a minority (20%) contained negative emotion, confirming that MySpace is an extraordinarily emotion‐rich environment. Females are likely to give and receive more positive comments than are males, but there is no difference for negative comments. It is thus possible that females are more successful social network site users partly because of their greater ability to textually harness positive affect.
Assessing global diffusion with Web memetics: The spread and evolution of a popular joke
Authors: Shifman Limor , Thelwall Mike
Published: July 2009

Memes are small units of culture, analogous to genes, which flow from person to person by copying or imitation. More than any previous medium, the Internet has the technical capabilities for global meme diffusion. Yet, to spread globally, memes need to negotiate their way through cultural and linguistic borders. This article introduces a new broad method,Web memetics, comprising extensive Web searches and combined quantitative and qualitative analyses, to identify and assess: (a) the different versions of a meme, (b) its evolution online, and (c) its Web presence and translation into common Internet languages. This method is demonstrated through one extensively circulated joke about men, women, and computers. The results show that the joke has mutated into several different versions and is widely translated, and that translations incorporate small, local adaptations while retaining the English versions' fundamental components. In conclusion, Web memetics has demonstrated its ability to identify and track the evolution and spread of memes online, with interesting results, albeit for only one case study.
Dose‐dependent pharmacokinetics and first‐pass effects of mirodenafil, a new erectogenic, in rats
Authors: Choi Young H. , Lee Young S. , Bae Soo H. , Kim Tae K. , Lee Bong‐Y. , Lee Myung G.
Published: July 2009

The pharmacokinetics of mirodenafil and its two metabolites, SK3541 and SK3544, after intravenous (5, 10, 20 and 50 mg/kg) and oral (10, 20 and 50 mg/kg) administration of mirodenafil, and the first‐pass effect of mirodenafil after intravenous, oral, intraportal, intragastric and intraduodenal (20 mg/kg) administration of mirodenafil were evaluated in rats. The pharmacokinetics of mirodenafil and SK3541 were dose‐dependent after both intravenous and oral administration of mirodenafil due to the saturable hepatic metabolism of mirodenafil. After oral administration of mirodenafil, approximately 2.59% of the oral dose was not absorbed, theFvalue was approximately 29.4%, and the hepatic and gastrointestinal first‐pass effects of mirodenafil were approximately 21.4% and 54.3% of the oral dose, respectively. The lowFvalue of mirodenafil in rats was mainly due to considerable hepatic and gastrointestinal first‐pass effects in rats. The equilibrium plasma‐to‐blood cell partition ratios of mirodenafil were independent of the initial blood mirodenafil concentrations of 1–10 µg/ml; the mean values were 1.08–1.21. The plasma binding values of mirodenafil to rat plasma was 87.8%. Copyright © 2009 John Wiley & Sons, Ltd.
Biomimetic potential of some methacrylate‐based copolymers: A comparative study
Authors: Zecheru Teodora , Filmon Robert , Rusen Edina , Mărculescu Bogdan , Zerroukhi Amar , Cincu Corneliu , Chappard Daniel
Published: July 2009

Preparation of new biocompatible materials for bone recovery has consistently gained interest in the last few decades. Special attention was given to polymers that contain negatively charged groups, such as phosphate, carboxyl, and sulfonic groups toward calcification. This present paper work demonstrates that other functional groups present also potential application in bone pathology. New copolymers of 2‐hydroxyethyl methacrylate with diallyldimethylammonium chloride (DADMAC), glycidyl methacrylate (GlyMA), methacrylic acid (MAA), 2‐methacryloyloxymethyl acetoacetate (MOEAA), 2‐methacryloyloxyethyltriethylammonium chloride (MOETAC), and tetrahydrofurfuryl methacrylate (THFMA) were obtained. The copolymers were characterized by FTIR, swelling potential, and they were submitted to in vitro tests for calcification and cytotoxicity evaluation. GlyMA and MOETAC‐containing copolymers show promising results for further in vivo mineralization tests, as a potential alternative to the classical bone grafts, in bone tissue engineering. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 966–973, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
From gene to protein
Authors: Nadeau Jay L.
Published: July 2009

This article describes a 3‐week intensive molecular biology methods course based upon fluorescent proteins, which is successfully taught at the McGill University to advanced undergraduates and graduates in physics, chemical engineering, biomedical engineering, and medicine. No previous knowledge of biological terminology or methods is expected, so the material could readily be adapted to earlier undergraduates or students in other fields. The course emphasizes hands‐on experience with one half‐hour of lecture and 3 and a half hours of laboratory 4 days per week, for a total of 39 hours. The materials are simple and low in cost and all software used is free, making the budget accessible to small universities and community colleges that possess basic teaching wet labs. Conceptual understanding is reinforced with lab reports and an independent final paper on a subject of the student's choice. The final paper describes a possible thesis project, not necessarily the student's own, with assessment based upon grasping of key concepts and methods of molecular biology.
A methods‐based biotechnology course for undergraduates
Authors: Chakrabarti Debopam
Published: July 2009

This new course in biotechnology for upper division undergraduates provides a comprehensive overview of the process of drug discovery that is relevant to biopharmaceutical industry. The laboratory exercises train students in both cell‐free and cell‐based assays. Oral presentations by the students delve into recent progress in drug discovery. Combination of lectures, hands‐on experiments, oral presentations, and accurate recording of laboratory data provides students a thorough training in biotechnology that better prepares them for the job market.
Problem‐solving test: Real‐time polymerase chain reaction
Authors: Szeberényi József
Published: July 2009

Terms to be familiar with before you start to solve the test: polymerase chain reaction, DNA amplification, electrophoresis, breast cancer, HER2 gene, genomic DNA, in vitro DNA synthesis, template, primer, Taq polymerase, 5′→3′ elongation activity, 5′→3′ exonuclease activity, deoxyribonucleoside triphosphates, DNA structure, proofreading, thermocycler, fluorescence.
The impact of corporate social responsibility associations on trust in organic products marketed by mainstream retailers: a study of Italian consumers
Authors: Perrini Francesco , Castaldo Sandro , Misani Nicola , Tencati Antonio
Published: July 2009

This paper investigates the determinants of consumer attitudes toward organic products marketed by mainstream retailers under a private label. Since organic products are credence goods, consumers cannot directly verify whether these products comply with official standards. Organic labels are the primary source of consumer trust in organics, but these labels must be noticed and understood before consumers will actively seek them out. In that some consumers may not prioritize product labels when they shop, it is sometimes up to retailers to strengthen consumer trust. Within the antecedents of this trust, we isolated the contribution of the corporate social responsibility associations held by consumers about retailers. We surveyed Italian customers interested in organics and found that they are more likely to trust the private‐label organic products sold by a retailer when it is considered socially responsible. Our results also show that consumer trust translates into brand loyalty and a willingness to pay a premium price for organic products. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Selective extraction of polyunsaturated triacylglycerols using a novel ionic liquid precursor immobilized on a mesoporous complexing adsorbent
Authors: Pham Patrisha J. , Pittman Charles U. , Li Tingyu , Li Min
Published: July 2009

Mesoporous silica (SBA‐15) synthesized by using Pluronic123 as the structure‐directing template was functionalized by imidazolium‐based ionic liquid precursors. Silver salts were then immobilized onto the supported ionic liquids using the incipient wetness impregnation technique. The separation of unsaturated species was achieved through the reversible and specific interaction between silver ions and carbon–carbon double bonds. This adsorbent was examined for the selective separation of polyunsaturated triacylglycerols (PUTAG) using High Pressure Liquid Chromatography (HPLC) with Evaporative Light Scattering Detection (ELSD) as the quantification methodology. AgBF4/SBA15·HPSiOEtIM·PF6 showed an adsorption capacity for linolenin of about 217 mg adsorbed/gram of sorbent. This adsorbent had good selectivity and a high capacity for the most highly unsaturated triacylglycerol when applied to a mixture of triacylglycerols with varying degrees of unsaturation. Consequently, a stepwise methodology was also developed to increase the recovery of the adsorbed components. This adsorbent retained its selectivity and capacity when recycled up to five times. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Enhancing the secretion of recombinant proteins by engineering N‐glycosylation sites
Authors: Liu Yan , Nguyen Anton , Wolfert Robert L. , Zhuo Shaoqiu
Published: July 2009

N‐glycosylation is important for the folding and quality control of membrane and secretory proteins. We used mutagenesis to introduce N‐glycosylation sequons in recombinant proteins to improve their secretion in HEK293 cells. Seven recombinant proteins, with or without endogenous N‐glycosylation sequons, were tested by this method. Our results indicate that N‐glycosylation sequons located at the N‐ or C‐terminal are glycosylated at high rates and thus the N‐ and C‐terminal may be convenient sites for effectively attaching oligosaccharide chains. More importantly, introduction of oligosaccharide chains at such positions has been found to improve the secretion levels for the majority of the recombinant proteins in our studies, regardless of endogenous N‐glycosylation, presumably by improving their folding in the endoplasmic reticulum. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Electrospun starch acetate nanofibers: Development, properties, and potential application in drug delivery
Authors: Xu Weijie , Yang Wen , Yang Yiqi
Published: July 2009

Electrospun starch acetate (SA) nanofibers with different degrees of substitution (DS) have been developed using formic acid/water as solvents, and their properties and potential applications in drug delivery have been studied. Although SA is biodegradable, biocompatible, and inexpensive, the mechanical properties and potential applications of SA nanofibers have not been studied. This research studied the effect of the solvent system, SA concentration, annealing time, and DS on the morphology and tenacity of SA nanofibers. The water stability of SA nanofibers and drug release profiles using diclofenac as a model drug with the sorption and the dissolution methods have also been investigated. It has been found that annealing not only increased the mechanical properties of SA nanofibers but also led to a low initial burst and a constant release rate. The results also showed that 90% (v/v) formic acid/water solvent system gave even and fine SA nanofibers and the highest tenacity obtained in this study was 17.9 MPa. The SA nanofibers with DS 2.3 retained about 78.0% and 48.0% of its tenacity after 16 and 32 days exposing to 50°C and 90% relative humidity comparing to 77.0% and 40.2% for SA nanofibers with DS 1.1, respectively. In addition, SA nanofibers with DS 2.3 had a lower initial burst and a more constant drug release rate than those with DS 1.1. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Purification and characterization of a transgenic corn grain‐derived recombinant collagen type I alpha 1
Authors: Zhang Cheng , Baez Julio , Pappu Kameshwari M. , Glatz Charles E.
Published: July 2009

Corn offers advantages as a transgenic host for producing recombinant proteins required at large volumes (1,000's of tons per year) and low cost (less than US$50/kg) by generating them as co‐products of biorefining. We describe the purification and characterization of a corn grain‐derived mammalian structural protein having such market characteristics: a full length recombinant collagen type I alpha 1 (rCIα1) chain. Material properties of interest are gelation behavior, which would depend on as yet unverified ability of corn to carry out post‐translational prolyl hydroxylation and formation of triple helical conformation. The starting material was grain where the expression of rCIα1 had been directed by an embryo‐specific promoter. Purification consisted of extraction at low pH followed by membrane and chromatographic steps to isolate rCIα1 for characterization. The amino acid composition and immunoreactivity of CIα1 was similar to that of an analogous native human CIα1 and to rCIα1 produced by the yeastPichia pastoris. Tandem mass spectrometry confirmed the primary sequence of the corn‐derived rCIα1 with 46% coverage. Fragments of the rCIα1chains were also observed, possibly caused by endogenous plant proteases. The corn‐derived rCIα1 had a low level of prolyl hydroxylation (∼1% versus 11%) relative to animal‐derived CIα1 and folded into its characteristic triple‐helical structure as indicated by its resistance to pepsin digestion below its melting temperature of 26oC. The 29 amino acid foldon fused to the C‐terminus to initiate triple helix formation was not cleaved from the rCIα1chains, but could be removed by pepsin treatment. © 2009 American Institute of Chemical Engineers Biotechnol. Prog. 2009