bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of steroid‐releasing sinus implants on postoperative medical and surgical interventions: an efficacy meta‐analysis
Authors: Han Joseph K. , Marple Bradley F. , Smith Timothy L. , Murr Andrew H. , Lanier Brent J. , Stambaugh James W. , Mugglin Andrew S.
Published: May 2012

Background:

Endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS) can be compromised by postoperative inflammation, polyposis, and adhesions, often requiring subsequent interventions. A bioabsorbable, steroid‐releasing sinus implant has been studied in 2 prospective, randomized clinical trials for its ability to preserve sinus patency and reduce medical and surgical interventions after ESS in patients with CRS. The objective of this study was to perform a meta‐analysis of the efficacy results from the 2 trials.

Methods:

The 2 prospective, randomized, double‐blinded, multicenter trials enrolled a total of 143 patients utilizing an intrapatient control design. Postoperative day 30 videos were obtained for each patient, randomly ordered, and presented to an independent panel of 3 otolaryngologists for grading of efficacy endpoints. The need for postoperative interventions, formation of polyposis, and adhesions were assessed. Results from the 2 studies were then pooled.

Results:

Implants were successfully placed in all 286 ethmoid sinuses. According to the grading done by the panel, drug‐releasing implants reduced postoperative interventions by 35% (p = 0.0008), lysis of adhesions by 51% (p = 0.0016), and oral steroid need by 40% (p = 0.0023), compared to controls. The relative reduction in frank polyposis was 46% (p < 0.0001).

Conclusion:

Early postoperative healing is a predictor of longer‐term success after sinus surgery. Evaluation of postoperative outcomes by a blinded independent panel demonstrates that steroid‐releasing implants that provide a sustained release of corticosteroid improve surgical outcomes by reducing frank polyp formation, sinus adhesions, and middle turbinate lateralization. Steroid‐releasing implants reduce the need for surgical intervention, and the need for oral steroid treatment. © 2012 ARS‐AAOA, LLC.
Emodin voltammetric sensor based on molecularly imprinted polymer membrane‐modified electrode using a multiple hydrogen bonds strategy
Authors: Yu Zerong , Yang Jiajian , Zhong Jinfeng , Wu Suqin , Xu Zhiguang , Tang Youwen
Published: May 2012

Similar to those in complementary nucleotides' base pairs, we present a novel molecularly imprinted electrochemical sensor for emodin, constructed using a multiple hydrogen bonds strategy. We obtained the sensor by in situ photopolymerization, using allobarbital as a new functional monomer. We optimized the conditions of membrane imprinting and the composition of adsorption solvent. This artificial receptor exhibits high selectivity for the template in comparison with closely related analogs, aloin A and simetryne. The sensor was successfully applied in determination of emodin levels in one of the traditional Chinese medicines, the content of emodin in Sanhuang tablets detected using the voltammetric sensor and high performance liquid chromatography (HPLC) were 0.249 ± 0.009 (mg/tablet) and 0.246 ± 0.007 (mg/tablet), respectively. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Water‐soluble star polymers with a phthalocyanine as the core and poly(ethylene glycol) chains as branches
Authors: Mineo Placido , Alicata Rossana , Micali Norberto , Villari Valentina , Scamporrino Emilio
Published: May 2012

Uncharged water‐soluble phthalocyanines (Pc's) and some metallophthalocyanines (Me‐Pc's) were prepared by means of a chemical modification of a commercial Pc or by a cyclic tetramerization reaction starting from 4‐nitrophthalonitrile derivatives. The necessary hydrophilicity for the water solubility of these Pc derivatives was achieved by the binding of eight 9‐methoxytriethyleneoxy branches on peripheral Pc positions or, alternatively, four or eight linear poly(ethylene glycol) methyl ether (PEGME; weight‐average molar mass = 350 or 750 g/mol) units. The chemical structure of these products was characterized by 1H‐NMR and matrix‐assisted laser desorption/ionization–time ‐of ‐flight mass spectrometric analysis. Finally, their solutions were examined by ultraviolet–visible and luminescence spectroscopy and dynamic light scattering experiments. All of the samples were water soluble, although the formation of small aggregates was ascertained by dynamic light scattering measurements. Furthermore, a lower scattered light intensity was measured for Pc derivatives with longer PEGME branches, which, probably playing a more negative role in the self‐assembly process, hindered the aggregation phenomenon. Preliminary data on their sensing ability are also reported. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Solid‐state graft polymerization of styrene in spherical polypropylene particles in the presence of montmorillonite
Authors: Fu Zhisheng , Sun Fangli , Fan Zhiqiang
Published: May 2012

In this work, cetyltrimethyl ammonium bromide and methacryloyloxyethyhrimethyl ammonium chloride were used to prepare organophilic montmorillonite (O‐MMT). Then, polypropylene (PP)–clay nanocomposites were prepared by the in situ grafting polymerization of styrene (St)‐containing O‐MMT onto PP with tert‐butyl perbenzoate as an initiator in the solid state. Fourier transform infrared spectroscopy, gel permeation chromatography, transmission electron microscopy, and X‐ray diffraction were applied to study the structure of the layered silicate and modified PP. The surfaces of the composites and, thus, the distribution of the clay in the PP matrix were characterized by scanning electron microscopy. The rheology and mechanical properties were studied and are discussed. According to the characterization results, OMMT and St were already grafted onto the PP main chain. Also, the intercalated structure of montmorillonite could be stabilized, and a stable exfoliated structure could be attained. Namely, intercalated PP/OMMT nanocomposites were obtained. The rheological results clearly show that these PP/OMMT nanocomposites had long‐chain‐branched structures. The peroxide modification of PP had minor effects on the tensile and bending strengths of the modified PP; however, this modification resulted in a significant reduction in the impact strength. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Copolymerization of potassium chloroacetate and potassium N‐chloroacetyl‐6‐aminohexanoate
Authors: Murase Sara Keiko , Franco Lourdes , Rodríguez‐Galán Alfonso , Puiggalí Jordi
Published: May 2012

The polymerization kinetics of potassium chloroacetate (MGL), potassium N‐chloroacetyl‐6‐aminohexanoate (MEA), and their mixtures was studied by Fourier transform infrared spectroscopy. The bulk polycondensation reaction was faster for MEA than for MGL but kinetic differences in the selected temperature range (110–130°C) were not large enough to make unfeasible copolymerization of both monomers. A decrease in the activation energy was deduced for the polycondensation of monomer mixtures with respect to that determined for the homopolymerization reaction of the predominant neat monomer. differential scanning calorimetry data also showed significant differences in the exothermic polycondensation peaks that suggested an effective copolymerization reaction and favored the kinetic process over the corresponding homopolymerization. The resulting new poly(ester amide)s were characterized by spectroscopy and thermal analysis. 1H NMR spectra of samples with high MEA content revealed the existence of hetero‐sequences whose ratio was slightly lower than that expected for a random polymerization of the two monomers. Samples with high molecular weights were only attained when the MGL molar ratio in the monomer mixture was lower than 65%. Calorimetric data showed that all samples were thermally stable and became amorphous for intermediate compositions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis, effectiveness, and working mechanism of humic acid‐{sodium 2‐acrylamido‐2‐methylpropane sulfonate‐co‐N,N‐dimethyl acrylamide‐co‐acrylic acid} graft copolymer as high‐temperature fluid loss additive in oil well cementing
Authors: Salami Oyewole Taye , Plank Johann
Published: May 2012

Monomers of 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS®), N,N–dimethyl acrylamide (NNDMA) and acrylic acid (AA) were grafted on humic acid as backbone by aqueous free radical copolymerization in such a manner that a graft copolymer possessing lateral terpolymer chains was obtained. Molar ratios between AMPS®, NNDMA, and AA were found to be 1 : 1.54 : 0.02 and the ratio between backbone and graft chain was 20 : 80 wt %. The synthesized fluid loss additive (FLA) was characterized by size exclusion chromatography (SEC), charge titration, and Brookfield viscometry. Thermogravimetric and SEC analysis revealed stretched backbone worm architecture for the polymer whereby humic acid constitutes the backbone decorated with lateral graft chains. Grafting was confirmed by SEC data (Rg) and by ineffectiveness of a blend of AMPS®‐NNDMA‐AA copolymer with humic acid. Their performance as high temperature FLA was studied at 150°C by measuring static filtration properties of oil well cement slurries containing 35% bwoc of silica fume and 1.2% bwoc AMPS®‐co‐itaconic acid retarder. At this temperature, 1.0% bwoc graft copolymer achieves API fluid loss value of 40 mL, thus confirming high effectiveness. The graft copolymer viscosifies cement slurries less than other common synthetic FLAs. The working mechanism of the graft copolymer was found to rely on adsorption onto surface of hydrating cement, as was evidenced by adsorption and zeta potential measurements. Adsorption is hardly affected by temperature and results in constriction of the filter cake pores. The study provides insight into performance of cement additives under the harsh conditions of high temperature and high pressure. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation of polyester polyols from unsaturated fatty acid
Authors: Junming Xu , Jianchun Jiang , Jing Li
Published: May 2012

Oleic acid is a typical unsaturated fatty acid that is found widely in vegetable oils. The objective of this investigation was to produce a new type of oleic‐based polyol from oleic acid. Possible advantages of this approach include the production of high‐performance polyurethane materials from renewable resources and value‐added research for oleic acid. Oleic‐based polyols were synthesized by a three‐step process consisting of epoxidation and ring‐opening reaction, followed by esterification. The synthesized polyols appeared as a viscous liquid at room temperature with hydroxyl numbers from 307 to 425 mg KOH/g. Preparation of polyurethane foams using oleic‐based polyols and isocyanate was studied. An environmentally friendly blowing agent, HCFC‐141b, together with a small amount of water, was used. The synthesized foams were characterized by FTIR, SEM, and TG/DSC. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effects of processing and functionalization methods on nylon‐6,6 nanocomposites with Helical‐ribbon carbon nanofibers
Authors: Rodriguez‐Pastor I. , Varela‐Rizo H. , Bortz D. R. , Montes de Oca G. , Guinea I. , Martin‐Gullon I.
Published: May 2012

Helical‐ribbon carbon nanofiber‐based nylon‐6,6 nanocomposites were obtained by three processing methods: in situ polymerization, solvent processing through coagulation, and melt compounding. Composites were produced with pristine carbon nanofibers and four functionalization treatments, HNO3, O3, air/NH3, and ethylenediamine, which form sets of two liquid/gas phase treatments and two acidic/basic treatments. Dispersion was monitored at the microscale by optical microscopy, showing clear differences depending on processing and functionalization methods. The best dispersion was obtained by solvent processing, whereas the most appropriate functionalizations were obtained by air/NH3 and ethylenediamine treatments. It was observed that lower aspect ratio CNFs and stronger CNF‐matrix interaction increased crystallization temperature. Percolation was not detected in the melt‐compounded composites while network formation was observed at concentrations of 2 wt % in the solvent and in situ processing methods, where a high‐aspect ratio was critical for performance. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Biodegradation of Phormium tenax/poly(lactic acid) composites
Authors: Fortunati E. , Puglia D. , Santulli C. , Sarasini F. , Kenny J. M.
Published: May 2012

The disintegration patterns of composites produced by a melt compounding process using 0, 20, 30, and 40 wt % of Phormium tenax fibers in poly(lactic acid) (PLA) matrix were studied for a period of 40 days in composting conditions. The characterization of PLA and PLA/phormium composites included disintegration measurements, differential scanning calorimetry, FTIR analysis, thermogravimetric analysis, and scanning electron microscopy. The two controlling factors for disintegrability appeared to be the crystallinity of PLA and phormium fiber content: in general, the matrix tends to disintegrate completely before the 40 days and also phormium fibers undergo a substantial degradation during this period of time. Measurements taken at 10, 20, 30, and 40 days confirm that the disintegration process progresses steadily, though most of it takes place between 20 and 30 days. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Controlled release of nonionic compounds from poly(lactic acid)/cellulose nanocrystal nanocomposite fibers
Authors: Xiang Chunhui , Taylor Alan G. , Hinestroza Juan P. , Frey Margaret W.
Published: May 2012

Poly(lactic acid)(PLA)/cellulose nanocrystal nanocomposite fibers were prepared by electrospinning at elevated temperature. Columbia Blue, a nonionic hydrophobic dye with a molecular weight and partition coefficient that mimics a systemic agrichemical, was incorporated into the fibers as a model compound. The release of Columbia Blue into water displayed little burst release. Diffusion‐controlled release of Columbia Blue was significantly influenced by the hydrophobicity of the electrospun PLA nanocomposite fibers and followed Fickian diffusion kinetics. The release of Columbia Blue by degradation‐controlled mechanism followed zero‐order, time‐independent Case II kinetics (n = 1.0). Increasing cellulose nanocrystal content in the fibers increased the fiber degradation rate and the Columbia Blue release rate. The plasticizing effect of Columbia Blue on the thermal properties of the electrospun nanocomposite fibers showed the miscibility of Columbia Blue inside the electrospun nanocomposite fibers. A greenhouse trial confirmed the anticipated trends of higher pesticide dosage causing higher whitefly mortality percentage. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013
Shape memory properties of polycaprolactone‐based polyurethanes prepared by reactive extrusion
Authors: Weng Shengguang , Xia Zhean , Chen Jianding , Gong Luanluan
Published: May 2012

The shape memory properties of polycaprolactone‐based polyurethanes (PCLUs) synthesized via a novel route of reactive extrusion were investigated in terms of the deformation amplitude, temperature, and rate by differential scanning calorimetry (DSC), dynamic mechanical analyzer, and polarized optical microscopy (POM). DSC analysis shows that the crystalline melting temperature and crystallinity of PCLU increased monotonically with increasing the average polymerization degree
$ ( \overline {DPn}) $
of poly(ε‐caprolactone) (PCL) block. The retract force increased with increasing the temperature and reached the maximum (6–7 MPa) within 45–55°C. Furthermore, a modified model with two recovery stages was postulated to elucidate the shape memory process, which is visually presented by POM analysis. The two stages of tensile and compressive recovery are distinguished by the inflexion temperature, within 43–48°C and 64–66°C, respectively. The shape fixity is about 60–70% and can be improved to 100% by choosing proper deformation temperature. The tensile deformation recovery ratio was 80–98% due to the water absorption, whereas the compressive deformation recovery ratio was almost 100%. Besides, recovery tests show that the lowest recovery temperature ranged from 24 to 47°C was influenced by the deformation temperature, rate and the PCL block
$ ( \overline {DPn}) $. Thus, the shape memory properties can be adjusted according to different purposes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation of methacrylic acid‐grafted chitin using cerium (IV) ion and its application in adsorbing paraquat
Authors: Hsu Shih‐Tong , Lin Wen‐Churng , Hsiao Wen‐Feng , Lee Cheng‐Chieh , Pan Ting‐Chung , Wang Tzu‐Ta , Huang Yu‐Miao
Published: May 2012

Chitin‐grafted‐poly(methacrylic acid) (chi‐g‐PMAA) was synthesized and characterized as an adsorbent of paraquat. Chi‐g‐PMAA copolymers were prepared using various concentrations of ammonium cerium(IV) nitrate (Ce+4) to determine the optimal concentration of Ce+4. Grafting was verified by differential scanning calorimeter thermograms, FTIR, and solid‐state 13C‐NMR spectra. A representative chi‐g‐PMAA copolymer was neutralized to a sodium salt (chi‐g‐PMANa) and used to adsorb paraquat. The adsorption equilibrium data are strongly related to both the Langmuir and the Freundlich isotherms. The maximal adsorption capacity is 147.0 mg/g‐adsorbent. This value exceeds those of Fuller's earth and activated carbon, which are the most common binding agents that are currently used for paraquat. The results suggest that chi‐g‐PMANa has potential as a paraquat adsorbent. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Rectorite powder modified by butadiene‐styrene‐vinyl pyridine rubber: Structure and its dispersion in styrene‐butadiene rubber
Authors: Wang Lei , Wang Yi‐Qing , Zhang Li‐Qun , Wu You‐Ping
Published: May 2012

Rectorite (REC) powders modified by butadiene‐styrene‐vinyl pyridine rubber (VPR) were prepared by spray drying, designated as REC‐VPRs. X‐ray diffraction (XRD), Scanning electron microscope (SEM), and transmission electron microscopy (TEM) analyses showed that in the REC‐VPRs, VPR did not intercalate into the intergallery of layers. However, compared with REC, the layers of REC‐VPRs had more wrinkles and piled loosely. To strengthen the interfacial interaction between VPR and REC, a REC‐VPR was treated by volatilized hydrochloric acid, resulting in the formation of ion bonds between REC and VPR, according to Fourier transform infrared spectra measurements. XRD analyses revealed that the intercalated structure emerged in acid treated REC‐VPR filled styrene‐butadiene rubber (SBR). However, the better dispersion was observed for the SBR composite filled with REC‐VPR without acid treatment, indicating that a proper interfacial interaction between REC and VPR is the key to improve the dispersion of REC layers in SBR. Acid treatment did not improve the tensile and tear strengths of the SBR composite filled with REC‐VPR. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci., 2013
Polyamide 66 nanocomposites based on organoclays treated with thermally stable phosphonium salts
Authors: Abdallah Wissam , Yilmazer Ulku
Published: May 2012

Purification of bentonite clays and their modification with two thermally stable (alkyl and aryl) phosphonium organic salts were investigated. The organoclays were subsequently melt compounded with Polyamide 66 (PA66), with and without the use of an elastomeric compatibilizer. The morphology, melt flow, thermal stability, and mechanical properties of the binary and ternary nanocomposites were studied. The bentonite clay was purified by sedimentation, resulting in higher cation exchange capacity and thermal stability in comparison with unpurified clay. These were then used in the synthesis of two thermally stable organoclays by replacing the interlayer sodium cations with two (alkyl and aryl) phosphonium surfactant cations to circumvent the problem of low temperature decomposition of quaternary ammonium organoclays usually used in polymer nanocomposites. The organoclay with aliphatic groups showed more compatibility with PA66 in comparison with the organoclay with aromatic groups. Thus, the use of organoclay with aliphatic groups resulted in nanocomposites with higher tensile strength, higher modulus, higher elongation at break, and higher impact strength in comparison with the nanocomposites produced from the organoclay with aromatic groups. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Conducting poly(styrene‐co‐divinylbenzene)/polypyrrole PolyHIPE composite foam prepared by chemical oxidative polymerization
Authors: Karimian Hossein , Moghbeli Mohammad Reza
Published: May 2012

Conducting poly(styrene‐co‐divinylbenzene)/polypyrrole (PPy) polyHIPE (polymerized high internal phase emulsion) composite foams were synthesized via chemical oxidative polymerization method. The effect of solvent and dopant type on the surface morphology and electrical conductivity of composite foams has been investigated. SEM micrographs showed that the morphology of PPy thin film on the internal surface of poly(styrene/divinylbenzene) (poly(St‐co‐DVB) polyHIPE support foam strongly depends on the solvent and dopant type used. Incorporation of dodecylbenzene solfunic acid‐sodium salt (DBSNa) as a dopant in chloroform solvent resulted in formation of a PPy thin film with higher molecular compact structure and electrical conductivity on the support foam as compared to other solvents and another dopant used. Fourier‐transform infrared spectroscopy was used to correlate the electrical conductivity of composite foams to their PPy structural parameters. As expected, the extended conjugation length of PPy in the presence of DBSNa dopant is the main reason for higher electrical conductivity of resultant composite foam. Electrical conductivity measurements revealed that the chemical aging of various conducting foams follows the first‐order kinetic model, which is a representative of a reaction‐controlled aging mechanism. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Development of antimicrobial stainless steel via surface modification with N‐halamines: Characterization of surface chemistry and N‐halamine chlorination
Authors: Bastarrachea Luis J. , Goddard Julie M.
Published: May 2012

N‐halamine modification of materials enables the development of antimicrobial materials whose activity can be regenerated after exposure to halogenated sanitizers. Surface and bulk modification of polymers by N‐halamines has shown great success, however, modification of inorganic substrates (e.g., stainless steel) remains an area of research need. Herein, we report the covalent surface modification of stainless steel to possess rechargeably antimicrobial N‐halamine moieties. Multilayers of branched polyethyleneimine and poly(acrylic acid) were immobilized onto the surface of stainless steel and the number of N‐halamines available to complex chlorine was quantified. Samples were characterized through contact angle, Fourier transform infrared spectroscopy, ellipsometry, dye assay for amine quantification, and X‐ray photoelectron spectroscopy. Increasing the number of multilayers from one to six increased the number of N‐halamines available to complex chlorine from 0.30 ± 0.5 to 36.81 ± 5.0 nmol cm−2. XPS and FTIR confirmed successful covalent layer‐by‐layer deposition of the N‐halamine multilayers. The reported layer‐by‐layer deposition technique resulted in a greater than seven‐fold increase of available N‐halamine compared to prior reports of N‐halamine surface modifications. The N‐halamine modified steel demonstrated antimicrobial activity (99.7% reduction) against the pathogen Listeria monocytogenes. Such surface modified stainless steel with increased N‐halamine functionality, and therefore potential for rechargeable antimicrobial activity, supports efforts to reduce cross‐contamination by pathogenic organisms in the food and biomedical industries. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The Arrangement of Fascicles in Whole Muscle
Authors: Infantolino Benjamin W. , Neuberger Thomas , Challis John H.
Published: May 2012

The architecture of the muscle fascicles, here meaning their lengths and their arrangement relative to one another, has important implications for the force a muscle can produce. Therefore, quantifying this architectural arrangement and understanding the implications of the architecture are important for understanding muscle function in vivo. There were two purposes of this study: (1) to assess, via blunt dissection, the number and the length of all the fascicles comprising the First Dorsal Interosseous (FDI) muscle and (2) to visually identify, via magnetic resonance imaging (MRI), the arrangement of the fascicles comprising the FDI. Simple blunt dissection of all the fascicles comprising four FDI muscles and their subsequent measurement demonstrated that the fascicles comprising the whole muscle were not as long as the muscle belly from which they were extracted. Muscle fascicles are surrounded by connective tissue hence the paths of the fascicles in two whole FDI muscles were identified via MRI by tracking the connective tissue surrounding the fascicles. The fascicles had a spiral pattern along the length of each muscle, within both muscles many of the fascicles were arranged in series with other fascicles. These architectural features of the fascicles of the FDI have important implications for the force–length and force–velocity properties of the whole muscle. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
The Prenatal Toxic Effect of Methylmercury on the Development of the Appendicular Skeleton of Rat Fetuses and the Protective Role of Vitamin E
Authors: Abd El‐Aziz Gamal S. , El‐Fark Magdy M.O. , Saleh Hamid A.M.
Published: May 2012

Methylmercury (MeHg) is an environmental contaminant that is found in many ecosystems. Many studies reported that MeHg toxicity is accompanied by increased lipid peroxidation that may lead to oxidative damage to DNA, RNA, and proteins. Vitamin E is considered as the most effective antioxidant preventing lipid peroxidation. The aim of this study was to evaluate the effects of MeHg exposure during pregnancy on the development of the appendicular skeleton in rat fetuses and whether vitamin E administration could reduce this toxicity. Positively mated adult female Sprague–Dawley rats were used and divided into the following experimental groups: control group, received only deionized water, and four MeHg treated groups received 1 mg of MeHg/kg/d, 2 mg of MeHg/kg/d, 1 mg of MeHg/kg/d plus 150 mg of vitamin E/kg/d, and 2 mg of MeHg/kg/d, plus 150 mg of vitamin E/kg/d starting from Day 0 of gestation. On Day 20 of gestation, the fetuses from the pregnant rats were extracted and the fetal growth parameters were evaluated. Skeletal evaluation of ossification of both fore‐ and hind‐limbs, and coxal bones were undertaken. Results showed that treatment with MeHg caused adverse effects on fetal growth parameters and ossification of the bones. The coadministration of vitamin E with MeHg revealed an improvement in these parameters. These results suggest that vitamin E may ameliorate some aspects of MeHg developmental toxicity. The underlying and human health implications warrant further investigations. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
IDENTIFICATION OF MYCOSIS‐RELATED GENES IN THEEASTERN SUBTERRANEAN TERMITE BY SUPPRESSION SUBTRACTIVE HYBRIDIZATION
Authors: Gao Qi , Tancredi Sarah E. , Thompson Graham J.
Published: May 2012

TheEastern subterranean termiteReticulitermes flavipes (Isoptera,Rhinotermitidae) is a cosmopolitan, structural pest that is the target of research into termite innate immunity. In this study, we use suppression subtractive hybridization to construct a normalized cDNAlibrary of genes excessively expressed upon fungal infection. At 24 h postinfection withMetarhizium anisopliae, the library revealed 182 expressed sequence tag (EST) clones that potentially represent immune responsive genes. The nucleotide sequence from a majority (97%) ofESTs assembled into a small number (n = 13) of contiguous sequences, with the remainder (n = 6) representing singletons. Our screen therefore captured as many as 19 different mRNAs highly expressed in response to the fungal pathogen at this time. Primary sequencing of all loci revealed that approximately half (n = 10) contained open reading frames with significant similarity to known proteins. These clones represent nuclear and mitochondrial coding genes, as well as putative long noncodingRNAgenes. Quantitative polymerase chain reaction analysis of coding genes on independently infected groups of worker termites confirms in each case that the transcripts identified from the library are up‐regulated postfungal infection. The genes identified here are relevant to future studies on termite biocontrol and social insect immunity.
Synthesis and Antimicrobial Evaluation of Novel Platensimycin Analogues
Authors: Plesch Eva , Bracher Franz , Krauss Jürgen
Published: May 2012

Since the isolation of the natural products platensimycin and platencin as new antibiotic lead structures, several total syntheses as well as syntheses of derivatives have been developed. Most of these approaches are very laborious and the target molecules are often produced in only poor overall yields. The following approach describes the synthesis of rather simple platensimycin analogues focussing on some structure elements that have previously been identified as being essential for binding to the Fab F enzyme in fatty acid biosynthesis. Two of the new analogues show significant antimicrobial activities.
Adhesion molecule expression in human synovial tissue
Authors: Johnson Bruce A. , Haines George K. , Harlow Lisa A. , Koch Alisa E.
Published: May 2012

Objective. We have previously shown that E‐selectin is expressed on endothelium in rheumatoid arthritis (RA) synovial tissues, and hence may be important in recruitment of leukocytes into the inflamed joint. In the present study, we determined whether other cellular adhesion molecules, including selectins and members of the integrin and immunoglobulin supergene families, are expressed in frozen synovium.

Methods. We employed immunohistochemical staining to determine the distribution of CD31 (PECAM), CD44 (hyaluronate receptor), CD62 (P‐selectin), Leu‐8 (L‐selectin), and the integrin subunits α5 (VLA‐5), α6 (VLA‐6), β1 (VLA 1–6), and β3 (vitronectin receptor), in synovial tissue from 9 RA and 9 osteoarthritis (OA) patients, and from 3 normal (NL) subjects.

Results. P‐selectin was expressed on vascular endothelium in all synovial tissues examined. L‐selectin and α5‐integrin, while expressed on a variety of cell types, were not differentially expressed on RA synovial tissues. Integrin subunits α6 and β1 were down‐regulated on some RA synovial tissue components. In contrast, CD31 was expressed to a greater extent on RA than on OA lining cells and macrophages (P < 0.05). CD44 was expressed to a greater extent on RA or OA macrophages, lining cells, and fibroblasts compared with NL (P < 0.05). Integrin subunit β3 was strongly expressed on RA synovial blood vessels compared with NL (P < 0.05).

Conclusion. The expression of integrins VLA 1–6, and selectins P and L is not up‐regulated in RA synovial tissues. CD31 and CD44 are up‐regulated on RA macrophages and lining cells, CD44 on RA fibroblasts, and β3‐integrin on RA blood vessels. The up‐regulation of CD31, CD44, and β3‐integrin in RA synovial tissues may help tip the balance of adhesive interactions toward passage and retention of leukocytes in the inflamed joint.
Suppression of interleukin‐2 and interleukin‐2 receptor biosynthesis by gold compounds in in vitro activated human peripheral blood mononuclear cells
Authors: Sfikakis Peter P. , Souliotis Vassillis L. , Panayiotidis Panayiotis P.
Published: May 2012

Objective. To further investigate the mechanism of action of gold compounds by studying their effects on interleukin‐2 (IL‐2) and IL‐2 receptor (IL‐2R) biosynthesis.

Methods. We cultured phytohemagglutinin‐ or anti‐CD3 antibody‐activated normal peripheral blood mononuclear cells (PBMC), as well as the erythroleukemic K562 cell line, in the presence of gold sodium thiomalate or auranofin. Tritiated thymidine incorporation assays, cytotoxicity assays, immunofluorescence analysis, enzyme‐linked immunosorbent assay, Northern blot, and RNA dot‐blot hybridization were used.

Results. Gold compounds, at concentrations attainable in vivo, inhibited the proliferation of normal PBMC, with no evidence of direct cytotoxicity. This inhibitory effect was associated with a dose‐dependent suppression of both IL‐2 and IL‐2R messenger RNA accumulation. In contrast, the same concentrations of gold compounds failed to inhibit the spontaneous proliferation of the IL‐2‐independent K562 cells.

Conclusion. Our findings suggest an IL‐2/IL‐2R‐mediated mechanism for suppression of lymphocyte proliferation by gold compounds, which might account for the immunomodulatory effects of gold in patients with rheumatoid arthritis.
Divergent T cell receptor γ repertoires in rheumatoid arthritis monozygotic twins
Authors: Kohsaka Hitoshi , Chen Pojen P. , Taniguchi Atsuo , Ollier William E. R. , Carson Dennis A.
Published: May 2012

Objective. To determine if the expressed T cell receptor (TCR) γ repertoire is altered in rheumatoid arthritis (RA).

Methods. Peripheral blood lymphocytes were collected from monozygotic twins who were either concordant or discordant for RA, or from a normal twin pair. TCR γ‐specific complementary DNA libraries were constructed using the anchored polymerase chain reaction. Gene usage was analyzed by plaque hybridization and sequencing.

Results. The expressed TCR VΓ repertoires both in RA patients and normal subjects were extremely diverse. Monozygotic twins who were concordant for RA expressed very different frequencies of TCR VΓ genes.

Conclusion. RA does not lead to a specific clonal expansion or deletion of TCR VΓ genes in peripheral blood.
Bone mineral density of the hip and of the anteroposterior and lateral dimensions of the spine in men with rheumatoid arthritis: Effects of low‐dose corticosteroids
Authors: Garton Mark J. , Reid David M.
Published: May 2012

Objective. To assess bone mineral density (BMD) in men with steroid‐treated rheumatoid arthritis (RA).

Methods. Dual‐energy x‐ray absorptiometry (DXA) was used to measure BMD in 40 men with RA, 20 of whom were receiving low‐dose corticosteroids (≤10 mg prednisolone daily), and in 20 healthy, age‐matched male controls.

Results. BMD was significantly reduced at the femoral neck and greater trochanter in both groups of RA patients, and at the spine from the anteroposterior dimension in the steroid‐treated group.

Conclusion. Low‐dose steroid therapy may induce excess axial osteopenia in men with RA.
Induction of autoimmune arthritis in rats by immunization with homologous rat type II collagen is restricted to the RT1av1 haplotype
Authors: Griffiths Marie M. , Cannon Grant W. , Leonard Patrice A. , Reese Van R.
Published: May 2012

Objective. To test for genetic differences in susceptibility to homologous (rat) type II collagen‐induced arthritis (RII‐CIA).

Methods. Nine inbred and RT1‐congenic rat strains were immunized with native rat type II collagen and evaluated for arthritis and IgG anti‐RII serum antibody titers.

Results. Only RT1av1 strains developed a high incidence of severe RII‐CIA and high titers of IgG anti‐RII serum antibody. Rats having RII‐CIA‐resistant haplotypes, RT1u,n,1 (which are known to develop CIA after immunization with heterologous type II collagen), were shown to also be susceptible to passive transfer of CIA with immune serum concentrates. Clinical expression of RII‐CIA was down‐regulated by non‐RT1 genes of BN origin. No strong gender differences in anti‐RII autoimmune responses were observed.

Conclusion. Arthritogenic, autoimmune reactivity to homologous RII is under strict genetic control but occurs readily in RT1av1 rats.
Computed tomography findings of pulmonary venoocclusive disease in scleroderma patients presenting with precapillary pulmonary hypertension
Authors: Günther S. , Jaïs X. , Maitre S. , Bérezné A. , Dorfmüller P. , Seferian A. , Savale L. , Mercier O. , Fadel E. , Sitbon O. , Mouthon L. , Simonneau G. , Humbert M. , Montani D.
Published: May 2012

Objective

Pulmonary venoocclusive disease (PVOD) is an uncommon form of pulmonary hypertension (PH) characterized by obstruction of small pulmonary veins. Pulmonary venous involvement has been reported in pathologic assessment of patients with systemic sclerosis (SSc) presenting with precapillary PH. High‐resolution computed tomography (HRCT) of the chest is a noninvasive diagnostic tool used to screen for PVOD. No HRCT data are available on SSc patients with precapillary PH. We undertook this study to evaluate the frequency and effect on prognosis of HRCT signs of PVOD in SSc patients with precapillary PH.

Methods

We reviewed chest HRCT data from 26 SSc patients with precapillary PH and 28 SSc patients without pulmonary arterial hypertension (PAH) or interstitial lung disease (ILD).

Results

The radiographic triad of HRCT signs of PVOD (lymph node enlargement [57.7% versus 3.6%], centrilobular ground‐glass opacities [46.2% versus 10.7%], and septal lines [88.5% versus 7.1%]) was significantly more frequent in SSc patients with precapillary PH than in SSc patients without PAH or ILD (all P < 0.005). Indeed, 61.5% of SSc patients with precapillary PH had ≥2 of these signs. Cardiomegaly (P < 0.0001), pulmonary artery enlargement (P < 0.0001), and pericardial effusion (P < 0.0005) were also significantly more frequent in SSc patients with precapillary PH. Pulmonary venous involvement was histologically confirmed in 2 patients with radiographic signs of PVOD. The presence of ≥2 radiographic signs of PVOD was associated with the occurrence of pulmonary edema after initiation of PAH‐specific therapy (in 8 of 16 patients) and with more rapid progression from diagnosis of PH to death.

Conclusion

HRCT signs of PVOD are frequently observed in SSc patients with precapillary PH, correlated with histologic assessment, and were associated with a high risk of pulmonary edema.
Yoga asanas as an effective form of experiential learning when teaching musculoskeletal anatomy of the lower limb
Authors: Bentley Danielle C. , Pang Stephen C.
Published: May 2012

Physical movement as a conduit for experiential learning within the academic context of anatomy is a strategy currently used in university dance education. This same approach can be applied to other movement‐based practices, for example, yoga. The primary purpose of this study was to pilot a novel teaching curriculum to yoga practitioners, based on Bruner's Theory of Instruction, which incorporated the four adaptive modes of Kolb's Theory of Experiential Learning. The secondary purpose was to assess the applicability of anatomical knowledge within the participants' yoga practice. Following the development of a curriculum appropriate for a spectrum of academic backgrounds, participants were recruited to attend a 2‐hour learning session within the Department of Anatomy at Queen's University in Kingston, Ontario, Canada. The learning session guided participants through the bones and muscles of the lower limb pertaining to five specific yoga poses. Based on participant feedback, the sessions were positively received and consistent. In addition, learning session participants were able to apply the anatomical information they were taught to their yoga practice 1‐month later. Bruner and Kolb's independent theories on curriculum design and effective learning practice were successfully incorporated to create a 2‐hour learning session. The potential use of experiential learning to compliment and/or enhance traditional didactic teaching in the academic context of anatomy should be further explored. Anat Sci Educ. © 2012 American Association of Anatomists.
Experimentelle Untersuchungen zur Ermüdung des Verbundes von Stahlbeton unter Querzug
Authors: Lindorf Alexander , Curbach Manfred
Published: May 2012

Es wurde ein Versuchsprogramm durchgeführt, bei dem die Erforschung des Verbundverhaltens zwischen Bewehrungsstahl und Beton unter kombinierter Beanspruchung aus Ermüdung und Querzug mit Rissbildung im Mittelpunkt stand. Die Untersuchungen für normalfesten und hochfesten Beton erfolgten an Ausziehkörpern mit einem durch Querzug hervorgerufenen Längsriss entlang des Bewehrungsstabes. Die hochzyklischen Versuche mit bis zu einer Million Lastwechseln beinhalteten vier verschiedene Schwingspiele mit variierenden Längsrissbreiten. Für den Vergleich der einzelnen Belastungsbedingungen wurde das Schlupfwachstum zwischen Bewehrungsstab und Beton in Abhängigkeit von der Lastwechselzahl herangezogen. Im Ergebnis stellte sich der Einfluss des Querzuges auf den Verbundwiderstand unter schwellender Belastung deutlich heraus. Je breiter der Längsriss war, desto stärker wuchs der Schlupf und desto eher versagte der Verbund. Auf der Grundlage des Schlupfwachstums wurden Dauerfestigkeitsdiagramme für die Bemessung gegen Verbundermüdungsversagen abgeleitet.

Experimental investigations on bond fatigue under transverse tension

An experimental program was carried out, which focused on investigating the bond behaviour between reinforcing steel and concrete under combined loading due to fatigue and transverse tension. The investigations for both, normal strength concrete and high performance concrete were performed on pull‐out specimens with a longitudinal crack along the reinforcing bar due to transverse tension. High cyclic tests, of up to one million load cycles, were carried out for four different load levels with varying crack widths. The increase in slip between reinforcing steel bar and concrete relative to the number of load cycles was taken into account to compare various loading conditions. The influence of transverse tension on bond resistance under repeated loading became evident. The wider the longitudinal crack widths, the greater the increase in slip was and the earlier bond failure occurred. Based on slip development predictions, constant life diagrams were derived for fatigue design against bond fatigue failure.
A Selenium‐Based Click AdoMet Analogue for Versatile Substrate Labeling with Wild‐Type Protein Methyltransferases
Authors: Willnow Sophie , Martin Michael , Lüscher Bernhard , Weinhold Elmar
Published: May 2012

Protein methylation is catalyzed by S‐adenosyl‐L‐methionine‐dependent protein methyltransferases (MTases), and this posttranslational modification serves diverse cellular functions. Some MTases seem to exhibit broad substrate specificities and comprehensive methods for target profiling are needed. Here we report the synthesis of a new AdoMet analogue for enzymatic transfer of a small propargyl group and labeling of modified proteins through copper‐catalyzed azide–alkyne cycloaddition (CuAAC). Replacement of sulfur by selenium strongly enhanced the stability of the progargylic cofactor, leading, in combination with better activation by the selenonium center, to higher enzymatic reactivity. A broad spectrum of wild‐type protein MTases acting on lysine, arginine, and glutamine residues accept this cofactor and modified substrates can be efficiently labeled by CuAAC click chemistry.
A completely fractured zotarolimus‐eluting stent in an aortocoronary saphenous vein bypass graft
Authors: Venero Carmelo V. , Aligeti Venkata R. , Wortham Dale C.
Published: May 2012

Drug‐eluting stents (DES) have significantly improved the rate of target vessel revascularization in comparison with bare metal stents. DES fracture was not reported in multicenter randomized clinical trials, but several case reports of DES fracture have been published, mostly with sirolimus‐eluting stents. DES fracture is associated with stent restenosis and thrombosis. We report a zotarolimus‐eluting stent fracture in an aortocoronary saphenous vein graft (SVG) bypass. The patient presented with chest pain and a non‐ST‐elevation myocardial infarction. He underwent cardiac catheterization that showed a complete fracture of a zotarolimus‐eluting stent in the ostium of a sequential SVG to the diagonal and obtuse coronary arteries. His management included coronary angioplasty and retrieval of the proximal fractured segment. We discuss the potential causes for this stent fracture and suggest caution when using a DES in an ostial location of a SVG bypass, especially in a highly mobile vessel. © 2012 Wiley Periodicals, Inc.
Recovery of left ventricular function after percutaneous revascularization of a left main chronic total occlusion
Authors: Khanna Pravien , Stilp Erik , Pfau Steven
Published: May 2012

Surgical revascularization of left main and/or three‐vessel coronary artery disease (CAD) is associated with improved survival in patients with left ventricular dysfunction when compared to medical therapy and can result in improved left ventricular ejection fraction (LVEF) [1]. Multivessel percutaneous coronary intervention (PCI) is equivalent to surgery regarding short and intermediate term mortality, and left main PCI has emerged as a safe and effective alternate to surgical revascularization [2]. However, outcomes of unprotected left main PCI in patients with severely depressed LVEF have not been examined. We report a patient with left main chronic total occlusion, multivessel CAD, and dilated cardiomyopathy, in whom complete revascularization via PCI resulted in decreased left ventricular size and improved LVEF. © 2012 Wiley Periodicals, Inc.
Novel use of a disposable digital pressure transducer to increase the safety of pericardiocentesis
Authors: Visweswaran Gautam K. , Lightfoot James , Gilchrist Ian C.
Published: May 2012

Cardiac tamponade represents a medical emergency necessitating emergent pericardiocentesis. Use of two‐dimensional echocardiography (ECHO) has improved the safety of pericardiocentesis, but procedural challenges may occur when performed in an emergent manner outside of the catheterization laboratory without availability of fluoroscopy and readily available pressure transducers. The most problematic situation is the initial finding of bloody fluid on aspiration where intrapericardial versus intravascular location of the needle must be determined. We report two cases of cardiac tamponade managed with the use of a novel, disposable lightweight digital pressure transducer to directly measure intrapericardial pressures during an ECHO guided pericardiocentesis. In both cases the fluid initially encountered was grossly bloody and rapid definition of whether this was pericardial fluid versus an inappropriately located needle in the vascular space was critical. This type of novel, disposable self contained manometer has the potential to further minimize complications associated with pericardiocentesis. It offers a cost effective alternative and answers questions about the shifting point of service for pericardiocentesis from the invasive cath lab to less costly locations (Drummond, et al., J Am Soc Echocardiogr 1998;11:433–435). © 2012 Wiley Periodicals, Inc.