bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of acetyl salycilic acid and ibuprofen in chronic liver damage induced by CCl4
Authors: Chávez Enrique , Castro‐Sánchez Luis , Shibayama Mineko , Tsutsumi Victor , Pérez Salazar Eduardo , Moreno Mario G. , Muriel Pablo 
Published: May 2011

ABSTRACTNon‐steroidal anti‐inflammatory drugs (NSAIDs) are drugs used primarily to treat inflammation, pain and fever. Their main mechanism of action is cyclooxygenase (COX) inhibition, and this enzyme has been linked to hepatotoxicity. The association of COX and liver injury has been, in part, due to the presence of COX‐2 isoform in damaged liver and the possible induction of this enzyme by profibrotic molecules like Transforming Growth Factor‐β (TGF‐β). The aim of this work was to evaluate the effects of two of the most used NSAIDs, acetyl salicylic acid (ASA) and ibuprofen (IBP), on experimental liver fibrosis. We formed experimental groups of rats including vehicle and drug controls, damage induced by chronic CCl4 (0.4 g kg−1, i.p., three times per week, for 8 weeks) administration, and CCl4 plus ASA (100 mg kg−1, p.o., daily) or IBP (30 mg kg−1, p.o., daily). Both drugs showed important antifibrotic properties. They inhibited COX‐2 activity, prevented oxidative stress measured as lipid peroxidation and glutathione content, and ASA inhibited partially and IBP totally increased TGF‐β expression and collagen content. ASA and IBP prevented translocation of NFκB to the nucleus and, interestingly, ASA induced MMP‐2 and MMP‐13 whereas IBP induced MMP‐2, MMP‐9 and MMP‐13. As a whole, these effects explain the beneficial effects of ASA and IBP on experimental liver fibrosis. Copyright © 2011 John Wiley & Sons, Ltd.
Portal hypertension correlates with splenic stiffness as measured with MR elastography
Authors: Nedredal Geir I. , Yin Meng , McKenzie Travis , Lillegard Joseph , Luebke‐Wheeler Jennifer , Talwalkar Jayant , Ehman Richard , Nyberg Scott L. 
Published: May 2011

AbstractPurpose:To investigate the correlation between MR elastography (MRE) assessed spleen stiffness and direct portal vein pressure gradient (D‐HVPG) measurements in a large animal model of portal hypertension.Materials and Methods:Cholestatic liver disease was established in adult canines by common bile duct ligation. A spin echo based echo planar imaging (EPI) MRE sequence was used to acquire three‐dimensional/three axis (3D/3‐axis) abdominal MRE data at baseline, 4 weeks, and 8 weeks. Liver biopsies, blood samples, and D‐HVPG measurements were obtained simultaneously.Results:Animals developed portal hypertension (D‐HVPG: 11.0 ± 5.1 mmHg) with only F1 fibrosis after 4 weeks. F3 fibrosis was confirmed after 8 weeks despite no further rise in portal hypertension (D‐HVPG: 11.3 ± 3.2 mmHg). Mean stiffnesses of the spleen increased over two‐fold from baseline (1.72 ± 0.33 kPa) to 4 weeks (3.54 ± 0.31 kPa), and stabilized at 8 weeks (3.38 ± 0.06 kPa) in a pattern consistent with changes in portal pressure. A positive correlation was observed between spleen stiffness and D‐HVPG (r2 = 0.86; P < 0.01).Conclusion:These findings indicate a temporal relationship between portal hypertension and the development of liver fibrosis in a large animal model of cholestatic liver disease. The observed direct correlation between spleen stiffness and D‐HVPG suggest a noninvasive MRE approach to diagnose and screen for portal hypertension. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Hepatic enhancement during the hepatobiliary phase after gadoxetate disodium administration in patients with chronic liver disease: The role of laboratory factors
Authors: Chernyak Victoria , Kim Jane , Rozenblit Alla M. , Mazzoriol Fernanda , Ricci Zina 
Published: May 2011

AbstractPurpose:To identify factors influencing hepatobiliary phase (HBP) hepatic enhancement on gadoxetate disodium‐enhanced MRI in patients with chronic liver disease (CLD).Materials and Methods:We retrospectively reviewed abdominal gadoxetate disodium‐enhanced MRIs and medical records of patients with (n = 97) and without (n = 48) CLD. CLD subgroups were formed based on normal/abnormal components of liver function tests (LFTs). Hepatic enhancement coefficients (HEKs) were calculated on MRI, and compared with LFTs and Model for End‐stage Liver Disease (MELD) scores.Results:The mean HEK was significantly lower (P < 0.0008) in the CLD than control group. The mean HEK was similar to controls in the subgroup with all normal LFTs (P = 0.09) and subgroup with normal direct bilirubin (DB) (p = 0.09), while it was significantly reduced (P < 0.0001) in the subgroup with elevated DB. For all other LFT components, regardless of normal or abnormal values, there was a significant reduction in the mean HEKs versus controls (all P values <0.01). There was a highly negative correlation between the mean HEKs in CLD subgroups and number of abnormal LFTs (r = −0.93) and MELD scores (r = −0.89).Conclusion:HBP hepatic enhancement in CLD patients is similar to those with no CLD as long as direct bilirubin remains normal. Higher MELD scores and higher number of abnormal LFT components are associated with reduced hepatic enhancement. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Disposable pipette extraction for gas chromatographic determination of codeine, morphine, and 6‐monoacetylmorphine in vitreous humor
Authors: Kovatsi Leda , Rentifis Konstantinos , Giannakis Dimitrios , Njau Samuel , Samanidou Victoria 
Published: May 2011

AbstractThe availability of a sensitive and rapid analytical method for the determination of opiates, and other substances of forensic interest, in a variety of biological specimens is of utmost importance to forensic laboratories. Solid‐phase extraction is very popular in the pre‐treatment of forensic samples. Nevertheless, a new approach, disposable pipette extraction (DPX), is gaining increasing interest in sample preparation. DPX has already been applied to the analysis of drugs of abuse in common biological matrices, such as urine and blood, but has not yet been evaluated on alternative biological samples, such as vitreous humor. The objective of this study was to evaluate the applicability of DPX on the analysis of opiates in vitreous humor. The currently developed method is fast, reliable, and easy to perform. The sensitivity, precision, and accuracy are satisfactory. Recoveries obtained are within the range of 72–91%, whereas the sample volume of vitreous humor required is only 100 μL.
Quantitative magnetization transfer imaging in human brain at 3 T via selective inversion recovery
Authors: Dortch Richard D. , Li Ke , Gochberg Daniel F. , Welch E. Brian , Dula Adrienne N. , Tamhane Ashish A. , Gore John C. , Smith Seth A. 
Published: May 2011

AbstractQuantitative magnetization transfer imaging yields indices describing the interactions between free water protons and immobile, macromolecular protons—including the macromolecular to free pool size ratio (PSR) and the rate of magnetization transfer between pools kmf. This study describes the first implementation of the selective inversion recovery quantitative magnetization transfer method on a clinical 3.0‐T scanner in human brain in vivo. Selective inversion recovery data were acquired at 16 different inversion times in nine healthy subjects and two patients with relapsing remitting multiple sclerosis. Data were collected using a fast spin‐echo readout and reduced repetition time, resulting in an acquisition time of 4 min for a single slice. In healthy subjects, excellent intersubject and intrasubject reproducibilities (assessed via repeated measures) were demonstrated. Furthermore, PSR values in white (mean ± SD = 11.4 ± 1.2%) and gray matter (7.5 ± 0.7%) were consistent with previously reported values, while kmf values were approximately 2‐fold slower in both white (11 ± 2 s–1) and gray matter (15 ± 6 s–1). In relapsing remitting multiple sclerosis patients, quantitative magnetization transfer indices were sensitive to pathological changes in lesions and in normal appearing white matter. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Higher order eigensensitivities‐based numerical method for the harmonic analysis of viscoelastically damped structures
Authors: Martinez‐Agirre M. , Elejabarrieta M. J. 
Published: May 2011

AbstractThis paper presents an efficient numerical method for the harmonic analysis of viscoelastically damped structural systems characterized by a frequency‐dependent structural damping matrix, making use of the complex mode superposition method. Departing from the undamped eigensolution, the proposed numerical method updates the complex and frequency‐dependent eigenpair avoiding the solution of a complex eigenproblem for each computational frequency. The complex eigenvalues and eigenvectors are updated within the desired tolerance by an adaptive step‐size control scheme using the first‐ and higher order eigenderivatives. The influence on the computation time of the considered number of eigenderivatives and the tolerance is discussed, and the efficiency of the proposed numerical method for the harmonic analysis of viscoelastically damped large‐ordered structural systems is proved. Finally, a practical application is presented where the harmonic response of a constrained layer damping cantilever beam subjected to a base motion is analyzed. The complex and frequency‐dependent eigenvalues and eigenvectors are computed, the modal contributions to the total response are determined, and the total response is approximated by the complex mode superposition method. Finally, the approximated response is validated with the exact one computed by the direct frequency method and with that experimentally measured. Copyright © 2011 John Wiley & Sons, Ltd.
Rapid weight loss and pain in the foot
Authors: Kong M‐F , Nisal K , Gregory R 
Published: May 2011

AbstractA 52‐year‐old man was referred with a 15kg weight loss over eight weeks associated with loss of appetite, nausea and early satiety. The day before admission he developed numbness and pins and needles in his left foot. He had hypertension and diabetes which was diagnosed three years previously. His control was very good with latest HbA1c of 6.6% (49mmol/mol) on metformin only. He had no evidence of microvascular complications. He had extensive investigations which included CT head, thorax, abdomen and pelvis, tumour markers, prostatic specific antigen, autoantibody screen and protein electrophoresis, which were all normal. Nerve conduction studies and electromyography confirmed right ulnar neuropathy and showed non‐specific neuropathy in the lower limbs. A diagnosis of diabetic neuropathic cachexia was made.It is important for this condition to be recognised and considered in patients with diabetes mellitus in order to avoid unnecessary and lengthy investigations. Copyright © 2011 John Wiley & Sons.
Polymer hybrid films based on silica and a poly(ether imide) containing phthalide groups
Authors: Hamciuc Elena , Hamciuc Corneliu , Bacosca Irina , Okrasa Lidia 
Published: May 2011

AbstractA study of thermal and electrical behavior of some silica‐containing poly(ether imide) films is presented. The hybrid films were prepared using a poly(amic acid) having phthalide groups and tetraethoxysilane via sol–gel technique and thermal cyclodehydration. Effects of inorganic particle content on polymer composite properties were investigated. Thermal and electrical characteristics of hybrid films were evaluated with respect to their structure. The films were flexible and showed good thermal properties having the initial decomposition temperature above 400°C and glass transition temperature in the range of 240–248°C. The dielectric spectroscopy revealed subglass transitions δ, γ, and β. At higher temperature, an α‐relaxation corresponding to the glass transition and the normal mode appeared. The dielectric constant values were in the range of 3.21–3.64 at 20°C and 10 kHz. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Removal of methylene blue dyes from wastewater using cellulose‐based superadsorbent hydrogels
Authors: Zhou Yiming , Fu Shiyu , Liu Hao , Yang Shaoping , Zhan Huaiyu 
Published: May 2011

AbstractSuperadsorbent cellulose‐graft‐acrylic acid (C‐g‐AA) hydrogels were successfully prepared via free radical polymerization in phosphoric acid solution. Phosphoric acid solution provides a homogeneous reaction system. The C‐g‐AA hydrogels have a porous network inner structure with cellulose as the backbone. The introduced carboxyl groups enable the C‐g‐AA hydrogels with good swelling property (swelling ratio 7327%) and excellent MB adsorption capacity (equilibrium adsorption amount 2197 mg g−1). The dynamic swelling behaviors of the hydrogels were tested, water intake of hydrogels followed a non‐Fickian type diffusion. The effects of mole ratio of AA to cellulose, the pH of adsorption medium and the initial MB concentration on dye adsorption capacity of hydrogels were investigated. The adsorption isotherm and kinetics fit the Langmuir model and the Pseudo‐second‐order model well, respectively. Desorption was carried out in weak acid solution and 70% MB could be removed, suggesting the C‐g‐AA hydrogels had the potential for reuse. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
On the differences in micro‐deformation mechanism between isotactic polypropylene and β‐nucleated isotactic polypropylene as revealed by the confocal laser scanning microscopy
Authors: Jancar J. , Kalfus J. , Balkova R. 
Published: May 2011

AbstractTo understand the toughness enhancement of β‐nucleated isotactic polypropylene (iPP) in comparison with iPP, the differences in the micro‐deformation mechanisms between the neat iPP and β‐nucleated iPP were visualized using the confocal laser scanning microscopy (CLSM). Structure of the α‐ and β‐spherulites situated close to the tip of the sharp starter crack has been investigated during tensile deformation in the viewing field of the CLSM. In the α‐spherulite of the neat iPP, highly localized inter‐ and intra‐spherulitic micro‐shear bands have been observed. In the β‐nucleated iPP, relatively uniform distribution of diffuse shear bands has been observed in the β‐phase, while the α‐phase remained relatively undeformed exhibiting only narrow intra‐spherulitic shear bands in the direction perpendicular to the loading direction. Delocalization of plastic deformation into diffuse shear bands in β‐nucleated iPP can explain its enhanced crack resistance compared with the neat iPP exhibiting highly localized shear banding. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Effect of extensional properties of polymer solutions on the droplet formation via ultrasonic atomization
Authors: Kim Yubin , Kim Hyungsu 
Published: May 2011

AbstractUltrasonic atomization was conducted using 2.4 MHz ultrasound generator to produce polymeric particles from the solutions of water‐soluble polymers like poly (ethylene oxide) (PEO), poly(vinyl alcohol) (PVA), and poly(vinyl pyrrolidone) (PVP). In the series of solutions containing these polymers of various molecular weights, the shear viscosity and surface tension were varied; such differences, however, could not account for the observed trends in the atomization behavior. It was found that the availability of droplet formation and size of the droplets depend strongly on the extensional characteristics of polymer solutions along with the apparent extensional viscosities and the longest relaxation times. The extensional properties of polymer solutions were effectively measured by capillary breakup extensional rheometry (CaBER) and provided a rational basis to understand the essential role of fluid viscoelasticity in ultrasonic atomization. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Synthesis and characterization of thiazolothiazole‐based polymers and their applications in polymer solar cells
Authors: Lee Sang Kyu , Kang In‐Nam , Lee Jong‐Cheol , Shin Won Suk , So Won‐Wook , Moon Sang‐Jin 
Published: May 2011

AbstractA novel series of thiazolothiazole (Tz)‐based copolymers, poly[9,9‐didecylfluorene‐2,7‐diyl‐alt‐2,5‐bis‐(3‐hexylthiophene‐2‐yl)thiazolo[5,4‐d]thiazole] (P1), poly[9,9‐dioctyldibenzosilole‐2,7‐diyl‐alt‐2,5‐bis‐(3‐hexylthiophene‐2‐yl)thiazolo[5,4‐d]thiazole] (P2), and poly[4,4′‐bis(2‐ethylhexyl)‐dithieno[3,2‐b:2′,3′‐d]silole‐alt‐2,5‐bis‐(3‐hexylthiophene‐2‐yl)thiazolo[5,4‐d]thiazole] (P3), were synthesized for the use as donor materials in polymer solar cells (PSCs). The field‐effect carrier mobilities and the optical, electrochemical, and photovoltaic properties of the copolymers were investigated. The results suggest that the donor units in the copolymers significantly influenced the band gap, electronic energy levels, carrier mobilities, and photovoltaic properties of the copolymers. The band gaps of the copolymers were in the range of 1.80–2.14 eV. Under optimized conditions, the Tz‐based polymers showed power conversion efficiencies (PCEs) for the PSCs in the range of 2.23–2.75% under AM 1.5 illumination (100 mW/cm2). Among the three copolymers, P1, which contained a fluorene donor unit, showed a PCE of 2.75% with a short‐circuit current of 8.12 mA/cm2, open circuit voltage of 0.86 V, and a fill factor (FF) of 0.39, under AM 1.5 illumination (100 mW/cm2). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Facile fabrication and self‐assembly of polystyrene–silica asymmetric colloid spheres
Authors: Yin Yuyong , Zhou Shuxue , You Bo , Wu Limin 
Published: May 2011

AbstractThis study presents a very simple method to fabricate organic–inorganic asymmetric colloid spheres. In this approach, when silica particles are used as the Pickering emulsifier to stabilize the monomer droplets (styrene) in water via acid–base interaction between silica particles and auxiliary monomer (1‐vinylimidazole), the exposed surfaces of silica particles are very easy to be locally modified with 3‐(trimethoxysilyl)propyl methacrylate. When water‐based initiator is added, polystyrene–silica asymmetric colloid spheres are highly yielded. The sizes of silica and polymer particles can be tunable. These organic–inorganic anisotropic colloid spheres can self‐assemble into an interesting thickness‐dependent film. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis and micellization of thermoresponsive galactose‐based diblock copolymers
Authors: Wang Ying , Li Xin , Hong Chunyan , Pan Caiyuan 
Published: May 2011

AbstractThermoresponsive double hydrophilic diblock copolymers poly(2‐(2′‐methoxyethoxy)ethyl methacrylate‐co‐oligo(ethylene glycol) methacrylate)‐b‐poly(6‐O‐methacryloyl‐D‐galactopyranose) (P(MEO2MA‐co‐OEGMA)‐b‐PMAGP) with various compositions and molecular weights were obtained by deprotection of amphiphilic diblock copolymers P(MEO2MA‐co‐OEGMA)‐b‐poly(6‐O‐methacryloyl‐1,2:3,4‐di‐O‐isopropylidene‐D‐galactopyranose) (P(MEO2MA‐co‐OEGMA)‐b‐PMAlpGP), which were prepared via reversible addition‐fragmentation chain transfer (RAFT) polymerization using P(MEO2MA‐co‐OEGMA) as macro‐RAFT agent. Dynamic light scattering and UV–vis studies showed that the micelles self‐assembled from P(MEO2MA‐co‐OEGMA)‐b‐PMAlpGP were thermoresponsive. A hydrophobic dye Nile Red could be encapsulated by block copolymers P(MEO2MA‐co‐OEGMA)‐b‐PMAGP upon micellization and released upon dissociation of the formed micelles under different temperatures. The galactose functional groups in the PMAGP block have specific interaction with HepG2 cells, and P(MEO2MA‐co‐OEGMA)‐b‐PMAGP has potential applications in hepatoma‐targeting drug delivery and biodetection. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Properties of ferrites with nonisometric shape of particles in organic coatings
Authors: Veselý David , Němec Petr , Kalendová Andréa 
Published: May 2011

AbstractThe pigments based on mixed metal oxides were synthesized at high temperature. The synthesized pigments XxZnyFe2O4(where X = Ca, Mg, x+y=1) had particles with a lamellar shape. The other type of synthesized ferrite pigments were core‐shell anticorrosion pigments where a layer corresponding to the XxZnyFe2O4 composition was applied onto the core – muscovite. The prepared pigments were characterized by means of X‐ray diffraction analysis, particle size distribution measurements, and scanning electron microscopy. The synthesized anticorrosion pigments were used to formulate alkyd paints that were tested in corrosion atmospheres. Good anticorrosion efficiency was detected for all the synthesized pigments. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties and crystallization kinetics of (TeO2)(ZnO)(TiO2) glasses
Authors: Kabalci Idris , Körpe Neşe Öztürk , Duran Tuğba , Özdemir Mustafa 
Published: May 2011

AbstractTernary tellurite based glasses in the (TeO2)(ZnO)(TiO2) system were prepared and its optical properties and crystallization kinetics investigated by using UV‐VIS spectrophotometer and differential thermal analyzer (DTA). All the glasses were transparent from visible to near infrared region for different ZnO glass compositions (x=0.05, 0.10, 0.20, and 0.30 mol). In the experiment, optical band gap and Urbach energies were estimated from the optical absorption spectra between 400 and 800 nm wavelength region. The observed results confirm that the addition of ZnO glass composition from 0.05 to 0.30 mol increases the optical band gap energy from 2.94 to 3.0 eV. In addition, glass transition (Tg), crystallization (Tp) and melting temperature (Tm) were determined by using the DTA plots. Finally, DTA results obtained with a heating rate of 20°C/min show that the peak crystallization temperature increases from 463 to 533 °C as the ZnO content increases from 0.05 to 0.30 mol (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Silver doped As2S3 chalcogenide films: A diffusion study
Authors: Lőrinczi Adam , Popescu Mihai , Sava Florinel , Velea Alin , Şimăndan Iosif‐Daniel 
Published: May 2011

AbstractPhoto‐diffusion of silver across an As2S3 thin film layer is studied, as continuing some earlier work about surface morphology modifications in double‐layer structures of Ag and As2S3, and some qualitative preliminary results on lateral Ag diffusion in As2S3 thin films. An estimation of the Ag film's dissolution rate and the diffusion front's advancement rate in As2S3 is given based on cross‐section measurements.In order to understand better the diffusion mechanism of Ag in As2S3, a structural model of the As2S3 matrix is used to estimate the amount of silver which might be hosted by an As2S3 layer in terms of molar ratio, and an interaction mechanism of the Ag with the chalcogenide matrix is proposed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)