bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incorporation of theophylline in a chitosan/chondroitin sulfate hydrogel matrix: In vitro release studies and mechanical properties according to pH changes
Authors: Lopes Laís C. , Fajardo André R. , Piai Juliana F. , Rubira Adley F. , Muniz Edvani C. 
Published: September 2012

AbstractHydrogels based on natural polymers have been widely applied as vehicles for controlled drug release because of their advantages and interesting properties. In this study, a physical hydrogel based on chitosan and chondroitin sulfate (CS) was formed under mild conditions to act as a potential device for the controlled release of theophylline (TH). In vitro CS and TH release studies at pH 2 and 8 were performed. Under acid conditions (pH 2), the fraction of TH released (ca. 0.87) was higher than that of CS (ca. 0.13). On the other hand, under basic conditions, the fractions released of both substances were similar (ca. 0.57). In addition, the system presented in this work was able to sustain the TH release in a controlled way for 30 h. The variation of the pH affected the mechanical properties and contributed to form ordered regions within the hydrogel network, as observed through compression tests and wide‐angle X‐ray scattering analysis. The experimental data and discussion presented in this article will contribute to the development of a new vehicle for controlled TH release; this ensures the efficacy of the drug and reduced the number of daily doses administered. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Rheological, thermal, and morphological properties of low‐density polyethylene/ultra‐high‐molecular‐weight polyethylene and linear low‐density polyethylene/ultra‐high‐molecular‐weight polyethylene blends
Authors: Chen Yang , Zou Huawei , Liang Mei , Liu Pengbo 
Published: September 2012

AbstractThe dynamic rheological behavior of low‐density polyethylene (LDPE)/ultra‐high‐molecular‐weight polyethylene (UHMWPE) blends and linear low‐density polyethylene (LLDPE)/UHMWPE blends was measured in a parallel‐plate rheometer at 180, 190, and 200°C. Analysis of the log–additivity rule, Cole–Cole plots, Han curves, and Van Gurp curves of the LDPE/UHMWPE blends indicated that the blends were miscible in the melt. In contrast, the rheological properties of LLDPE/UHMWPE showed that the miscibility of the blends was decided by the composition of LLDPE. The differential scanning calorimetry results and scanning electron microscopy photos of the LLDPE/UHMWPE blends were consistent with the rheological properties, whereas with regard to the thermal and morphological properties of LDPE/UHMWPE blends, the results reveal three endothermic peaks and phase separation, which indicated a liquid–solid phase separation in the LDPE/UHMWPE blends. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Elucidation of polymer wear resistance via nanoscale healing and fracture of sintered polystyrene particles
Authors: Mohammadi H. , Mohammadi N. , Kheirabadi M. 
Published: September 2012

AbstractPolymer wear resistance evolution was studied based on nanoscale healing and fracture of a model polyinterface system: sintered film of uniform submicron polystyrene particles. The observed phenomenon was divided into three regimes namely interdiffusion, trough, and recovery, respectively. Film annealing up to 10 min in interdiffusion regime enhanced wear resistance with a 3.8 power dependence on interpenetration depth. Further annealing led to a severe wear resistance decrease, trough regime. Wear resistance then showed a sharp increase followed by a gradual rise to a plateau, recovery regime. Surfactants preservation during film formation shifted whole wear resistance‐annealing time curve to shorter times, decreased differentiations among observed regimes and reduced wear resistance power dependence on interpenetration depth to 2.3. Aforementioned regimes were also discernible in impact strength‐annealing time curves but without the steep rise of the recovery regime. Wear resistance scaled impact strength with a 0.67 power by omitting trough regimes data points. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis of polyvinylidene fluoride (PVDF) membranes for protein binding: Effect of casting thickness
Authors: Ahmad A. L. , Ideris N. , Ooi B. S. , Low S. C. , Ismail A. 
Published: September 2012

AbstractMicroporous polyvinylidene fluoride (PVDF) membranes were synthesized from PVDF/N‐methyl‐2‐pyrrolidinone (NMP) solutions using an immersion–precipitation method with a 2‐propanol/water mixture as a soft coagulant. The effects of membrane thickness on pore size distribution and surface/cross‐section morphology were studied using capillary flow porometry and scanning electron microscopy (SEM), respectively. All the synthesized membranes had a small range of pore size distribution, with the pore size decreasing with increasing casting thickness. The semicrystalline PVDF membranes demonstrated significant variations in morphology under SEM observation, with the existence of polymer agglomeration at a casting thickness of 500 μm and above. The protein binding capacity was observed to be highest at a casting thickness of 400 μm, where optimum pore morphology provided a large surface area for protein binding. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The effect of the diphenylamino side group on the reduction of the molecular interaction between polyurethane copolymer chains
Authors: Chung Yong‐Chan , Lee Seul Bee , Chul Chun Byoung 
Published: September 2012

AbstractPolyurethane (PU) with a diphenylamino side group is tested for low temperature flexibility at −30°C and compared with a linear PU without the diphenylamino side group. The PU is composed of 4,4′‐methylenebis(phenylisocyanate) (MDI), poly(tetramethyleneglycol) (PTMG), 1,4‐butanediol (BD), and the diphenylamino group that is grafted to PU chains by a second MDI. The mechanical and shape memory properties of these two types of PU, which differ in the PTMG and the diphenylamino group content, are compared. In the best case, a 306% increase in the maximum stress compared with the linear polymer is attained with a little decrease in the strain. Shape recovery at 45°C increases to 94% and remains ∼90% after four cyclic tests. Low temperature flexibility can be improved by increasing the diphenylamino content. The PU with a diphenylamino side group demonstrates the low temperature flexibility at −30°C, whereas the linear PU must be warmed to room temperature to attain the same degree of flexibility. The exceptional low temperature flexibility is analyzed and is discussed together with the experimental data. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Polyurethane foams from melamine solutions in reactive solvents based on ethyl methyl ketone
Authors: Głowacz‐Czerwonka Dorota 
Published: September 2012

AbstractThis work presents conditions and method for obtaining foamed melamine–formaldehyde–butanone (Mel‐F‐MEK) materials of improved thermal stability. They were obtained from melamine solution in reactive solvents based on ethyl methyl ketone and 4,4′‐diphenylmethane diisocyanate. Some properties of obtained polyurethane foams were examined, e.g., apparent density, water absorption, dimensional stability, thermal conductivity, flammability, as well as static and dynamic thermal stability and compressive strength. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Photopolymerized hydrogel composites from poly(ethylene glycol) and hydroxyapatite for controlled protein delivery in vitro
Authors: Lin Genyao , Tarasevich Barbara 
Published: September 2012

AbstractThe incorporation of hard particles into soft hydrogels can improve the mechanical properties and provide necessary bioactivity to the hydrogels for desired biomedical applications. Hydrogel composites containing hydroxyapatite (HA) are promising materials for orthopedic applications. In this study, injectable poly(ethylene glycol) (PEG) hydrogel precursor solutions containing HA particles and model protein bovine serum albumin (BSA) were synthesized in situ by photopolymerization. In vitro BSA release properties from the hydrogel composites containing various amounts of HA were investigated and discussed. Fourier transform infrared spectroscopy and scanning electron microscopy were employed to investigate the interaction between HA and the hydrogel network and the morphology of the hydrogel composites. It is found that PEG hydrogel composites containing HA sustained the release of BSA for at least 5 days and the presence of HA slowed down BSA release. Photopolymerized hydrogel composites containing HA may find potential use as a drug delivery matrix for orthopedic tissue engineering. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Long‐term safety profile of belimumab plus standard therapy in patients with systemic lupus erythematosus
Authors: Merrill Joan T. , Ginzler Ellen M. , Wallace Daniel J. , McKay James D. , Lisse Jeffrey R. , Aranow Cynthia , Wellborne Frank R. , Burnette Michael , Condemi John , Zhong Z. John , Pineda Lilia , Klein Jerry , Freimuth William W. ,   on behalf of the LBSL02/99 Study Group
Published: September 2012

AbstractObjectiveTo evaluate the safety profile of long‐term belimumab therapy combined with standard therapy for systemic lupus erythematosus (SLE) in patients with active disease.MethodsPatients who were randomized to receive intravenous placebo or belimumab 1, 4, or 10 mg/kg, plus standard therapy, and completed the initial 52‐week double‐blind treatment period were then allowed to enter a 24‐week open‐label extension phase. During the extension period, patients in the belimumab group either received the same dose or were switched to 10 mg/kg and patients in the placebo group were switched to belimumab 10 mg/kg. Patients who achieved a satisfactory response during the 24‐week extension period were allowed to participate in the long‐term continuation study of monthly belimumab 10 mg/kg. Adverse events (AEs) and abnormal laboratory results were analyzed per 100 patient‐years in 1‐year intervals.ResultsOf the 364 patients who completed the 52‐week double‐blind treatment period, 345 entered the 24‐week extension, and 296 continued treatment with belimumab in the long‐term continuation study. Safety data through 4 years of belimumab exposure (1,165 cumulative patient‐years) are reported. Incidence rates of AEs, severe/serious AEs, infusion reactions, infections, malignancies, grades 3/4 laboratory abnormalities, and discontinuations due to AEs were stable or declined during 4‐year belimumab exposure. The most common AEs included arthralgia, upper respiratory tract infection, headache, fatigue, and nausea. Serious infusion reactions were rare: only 1 occurred during the 4‐year followup period. Rates of serious infection decreased from 5.9/100 patient‐years to 3.4/100 patient‐years, and no specific type of infection predominated.ConclusionBelimumab added to standard therapy was generally well‐tolerated over the 4‐year treatment period in patients with SLE, which suggests that belimumab can be administered long term with an acceptable safety profile.
Systematic review and meta-analysis of retroperitoneoscopic versus laparoscopic adrenalectomy
Authors: Constantinides V A , Christakis I , Touska P , Palazzo F F 
Published: September 2012

Abstract

Background
Laparoscopic adrenalectomy (LA) has replaced open adrenalectomy as the standard operation for non-malignant adrenal tumours. Retroperitoneoscopic adrenalectomy (RA) is an increasingly popular alternative minimally invasive approach. Advocates of each technique claim its superiority, but the issue has yet to be resolved and conclusions are complicated by the existence of a lateral (LRA) and true posterior (PRA) RA.

Methods
A literature search was performed for all comparative studies of RA versus LA. Meta-analysis was performed according to PRISMA guidelines. Odds ratios and standardized mean differences (SMD) were used to compare dichotomous and continuous outcomes respectively.

Results
Twenty-two studies were included, reporting on 1257 LAs, 471 LRAs and 238 PRAs. Both PRA and LRA were associated with a reduced length of hospital stay: SMD − 1·45 (95 per cent confidence interval − 2·76 to − 0·14) and − 0·54 (−1·04 to − 0·03) days respectively compared with LA. Interstudy heterogeneity was present throughout the comparisons of hospital stay. When considering only the two randomized clinical trials (RCTs) there was no statistically significant difference in this outcome. One RCT, however, found a reduction in the median time to convalescence of 2·4 weeks in the LRA group. There were no differences in duration of operation, blood loss, time to ambulation and oral intake, or complication rates between techniques.

Conclusion
RA overall has equivalent outcomes to LA but may be associated with a shorter hospital stay.
Intramolecular Hydroamination Reactions Catalyzed by Neutral and Cationic Group IV Pyridylamido Complexes
Authors: Luconi Lapo , Rossin Andrea , Tuci Giulia , Germain Stéphane , Schulz Emmanuelle , Hannedouche Jérôme , Giambastiani Giuliano 
Published: September 2012

AbstractZrIV and HfIV benzyl (neutral or cationic) and amido catalysts stabilized by pyridylamido ligands are found to be good candidates for the intramolecular hydroamination/cyclization of primary and secondary aminoalkenes. In particular, cationic monobenzyl derivatives have shown remarkable catalytic activity for the production of five and six‐membered N‐containing heterocycles from secondary amino alkenes. In addition, ZrIV and HfIV amido derivatives that are produced by a temperature‐controlled prototropic rearrangement have provided evidence of the central role played by the metal coordination sphere in promoting such catalytic transformations efficiently.
CD4+CD25+CD127− assessment as a surrogate phenotype for FOXP3+ regulatory T cells in HIV‐1 infected viremic and aviremic subjects
Authors: Saison Julien , Demaret Julie , Venet Fabienne , Chidiac Christian , Malcus Christophe , Poitevin‐Later Francoise , Tardy Jean‐Claude , Ferry Tristan , Monneret Guillaume 
Published: September 2012

AbstractBackground:Although likely pivotal, the role of regulatory T cells (Tregs) in HIV pathogenesis remains elusive. This can be partly explained by analytical issues regarding their phenotypic identification in clinical studies. Instead of intracellular FOXP3 staining, CD4+CD25+CD127− phenotype has been proposed as an alternative to identify Tregs in clinical samples. However, its use remains controversial in viremic patients. Therefore, the objective of the present study was to assess the correlation between frequencies of CD4+CD25+CD127− and CD4+CD25+FOXP3+ lymphocytes in viremic and matched aviremic HIV‐infected patients.Methods:Peripheral blood was collected from HIV‐1 infected patients. Eleven viremic patients (Viral Load > 40 copies/mL) were matched (age, sex, CD4+ cell number) with 8 aviremic patients under highly active antiretroviral therapy (HAART). Fresh whole blood was immediately stained to analyze by flow cytometry the correlation between CD4+CD25+CD127− and the reference phenotype CD4+CD25+FOXP3+ lymphocytes in the same tube (four color staining CD4/CD25/CD127/FOXP3 for concomitant analysis of cell surface and intracellular markers).Results:In both groups, no significant differences were observed when comparing CD4+CD25+CD127− and CD4+CD25+FOXP3+ cell frequencies. In line, a strong correlation between CD4+CD25+CD127− and CD4+CD25+FOXP3+ lymphocyte percentages was observed in the whole patient population (r: 0.948, P < 0.001) or each group separately: aviremic (r: 0.968, P < 0.001), viremic (r: 0.9, P < 0.001). Finally, we found that most CD4+FOXP3+ cells were indeed CD25+CD127−, both in viremic and aviremic groups (88.5% and 90.9%, respectively).Conclusions:We observed that CD4+CD25+CD127− phenotype is a good and easy‐to‐perform surrogate identification strategy for FOXP3+ regulatory T cells in both viremic and aviremic HIV‐1‐infected subjects. Thus, it represents a useful tool for monitoring Tregs in clinical research studies based on large cohorts of patients prospectively monitored, including HIV‐infected subjects. © 2012 International Clinical Cytometry Society
Evaluation of therapeutic response to concurrent chemoradiotherapy in patients with cervical cancer using diffusion‐weighted MR imaging
Authors: Kim Hyun Su , Kim Chan Kyo , Park Byung Kwan , Huh Seung Jae , Kim Bohyun 
Published: September 2012

AbstractPurpose:To investigate the changes in apparent diffusion coefficients (ADCs) in cervical cancer patients receiving concurrent chemoradiotherapy (CCRT), and to assess the relationship between tumor ADCs or changes in tumor ADCs and final tumor responses to therapy.Materials and Methods:Twenty‐four patients with cervical cancer who received CCRT were examined with 3 Tesla (T) MRI including diffusion‐weighted imaging (DWI). All patients had three serial MR examinations: before therapy (pre‐Tx); at 4 weeks of therapy (mid‐Tx); and 1 month after completion of therapy (post‐Tx). At each examination, ADC was measured in tumors and normal gluteus muscles. Final tumor response as determined by change in tumor size or volume using MRI was correlated with tumor ADCs at each therapeutic time or changes in tumor ADCs at mid‐Tx.Results:From pre‐Tx to post‐Tx, mean tumor ADCs were 0.88, 1.30, and 1.47 × 10−3 mm2/s in sequence (P < 0.001), while those of normal gluteus muscles were 1.24, 1.29, and 1.21 × 10−3 mm2/s in sequence (P > 0.05). At mid‐Tx, tumor ADCs and changes in tumor ADCs had a significant correlation with final tumor size responses (P = 0.029 and 0.025, respectively). However, the tumor ADC values at pre‐Tx were not associated with the final tumor size response (P = 0.47). The final tumor volume response was not associated with tumor ADC at pre‐Tx or mid‐Tx (P > 0.05) or changes in tumor ADCs at mid‐Tx (P > 0.05).Conclusion:DWI may have potentials in evaluating the therapeutic response to CCRT in patients with cervical cancer. J. Magn. Reson. Imaging 2013;37:187–193. © 2012 Wiley Periodicals, Inc.
T2‐based arterial spin labeling measurements of blood to tissue water transfer in human brain
Authors: Gregori Johannes , Schuff Norbert , Kern Rolf , Günther Matthias 
Published: September 2012

AbstractPurpose:To investigate blood to tissue water transfer in human brain, in vivo and spatially resolved using a T2‐based arterial spin labeling (ASL) method with 3D readout.Materials and Methods:A T2‐ASL method is introduced to measure the water transfer processes between arterial blood and brain tissue based on a 3D‐GRASE (gradient and spin echo) pulsed ASL sequence with multiecho readout. An analytical mathematical model is derived based on the General Kinetic Model, including blood and tissue compartment, T1 and T2 relaxation, and a blood‐to‐tissue transfer term. Data were collected from healthy volunteers on a 3 T system. The mean transfer time parameter Tbl→ex (blood to extravascular compartment transfer time) was derived voxelwise by nonlinear least‐squares fitting.Results:Whole‐brain maps of Tbl→ex show stable results in cortical regions, yielding different values depending on the brain region. The mean value across subjects and regions of interest (ROIs) in gray matter was 440 ± 30 msec.Conclusion:A novel method to derive whole‐brain maps of blood to tissue water transfer dynamics is demonstrated. It is promising for the investigation of underlying physiological mechanisms and development of diagnostic applications in cerebrovascular diseases. J. Magn. Reson. Imaging 2013;37:332–342. © 2012 Wiley Periodicals, Inc.
Direct MR arthrography of the shoulder under axial traction: Feasibility study to evaluate the superior labrum‐biceps tendon complex and articular cartilage
Authors: Becce Fabio , Richarme Delphine , Omoumi Patrick , Djahangiri Ali , Farron Alain , Meuli Reto , Theumann Nicolas 
Published: September 2012

AbstractPurpose:To assess the value of adding axial traction to direct MR arthrography of the shoulder, in terms of subacromial and glenohumeral joint space widths, and coverage of the superior labrum‐biceps tendon complex and articular cartilage by contrast material.Materials and Methods:Twenty‐one patients investigated by direct MR arthrography of the shoulder were prospectively included. Studies were performed with a 3 Tesla (T) unit and included a three‐dimensional isotropic fat‐suppressed T1‐weighted gradient‐recalled echo sequence, without and with axial traction (4 kg). Two radiologists independently measured the width of the subacromial, superior, and inferior glenohumeral joint spaces. They subsequently rated the amount of contrast material around the superior labrum‐biceps tendon complex and between glenohumeral cartilage surfaces, using a three‐point scale: 0 = no, 1 = partial, 2 = full.Results:Under traction, the subacromial (Δ = 2.0 mm, P = 0.0003), superior (Δ = 0.7 mm, P = 0.0001) and inferior (Δ = 1.4 mm, P = 0.0006) glenohumeral joint space widths were all significantly increased, and both readers noted significantly more contrast material around the superior labrum‐biceps tendon complex (P = 0.014), and between the superior (P = 0.001) and inferior (P = 0.025) glenohumeral cartilage surfaces.Conclusion:Direct MR arthrography of the shoulder under axial traction increases subacromial and glenohumeral joint space widths, and prompts better coverage of the superior labrum‐biceps tendon complex and articular cartilage by contrast material. J. Magn. Reson. Imaging 2013;37:1228–1233. © 2012 Wiley Periodicals, Inc.
Magnetization transfer‐based 3D visualization of foot peripheral nerves
Authors: Mekle Ralf , Mortamet Benedicte , Granziera Cristina , Krueger Gunnar , Chevrey Nicolas , Theumann Nicolas , Gambarota Guilio 
Published: September 2012

AbstractPurpose:To investigate magnetization transfer (MT) effects as a new source of contrast for imaging and tracking of peripheral foot nerves.Materials and Methods:Two sets of 3D spoiled gradient‐echo images acquired with and without a saturation pulse were used to generate MT ratio (MTR) maps of 260 μm in‐plane resolution for eight volunteers at 3T. Scan parameters were adjusted to minimize signal loss due to T2 dephasing, and a dedicated coil was used to improve the inherently low signal‐to‐noise ratio of small voxels. Resulting MTR values in foot nerves were compared with those in surrounding muscle tissue.Results:Average MTR values for muscle (45.5 ± 1.4%) and nerve (21.4 ± 3.1%) were significantly different (P < 0.0001). In general, the difference in MTR values was sufficiently large to allow for intensity‐based segmentation and tracking of foot nerves in individual subjects. This procedure was termed MT‐based 3D visualization.Conclusion:The MTR serves as a new source of contrast for imaging of peripheral foot nerves and provides a means for high spatial resolution tracking of these structures. The proposed methodology is directly applicable on standard clinical MR scanners and could be applied to systemic pathologies, such as diabetes. J. Magn. Reson. Imaging 2013;37:1234–1237. © 2012 Wiley Periodicals, Inc.