bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of polymorphism in MicroRNA 219‐1 with clearance of hepatitis B virus infection
Authors: Cheong Jae Youn , Shin Hyoung Doo , Kim Yoon Jun , Cho Sung Won 
Published: March 2013

AbstractPolymorphisms in the primary microRNA region may be associated with natural course of hepatitis B virus (HBV) infection. This study evaluated if the mircoRNA 219‐1 (miR‐219‐1) polymorphism can influence the susceptibility towards persistence of HBV infection and the progression to hepatocellular carcinoma (HCC) in patients with chronic HBV infection. A total of 1,439 individuals having either past or present evidence of HBV infection were enrolled for the study. The subjects were divided into four groups; (1) spontaneous recovery (n = 404), (2) chronic HBV carrier (n = 313), (3) chronic HBV carrier with cirrhosis (n = 305), and (4) hepatocellular carcinoma (n = 417). Genotyping was performed at three polymorphic variants (rs421446, rs107822, and rs213210) in the pri‐miRNA region of miR‐219‐1. The rs421446 T allele was found to be strongly associated with HBV clearance (OR = 0.73, P = 0.0005 in a codominant model and OR = 0.67, P = 0.0009 in a dominant model, OR = 0.69, P = 0.04 in a recessive model, respectively). The rs107822 G allele was also found to be associated with HBV clearance (OR = 0.79, P = 0.008 in a codominant model and OR = 0.72, P = 0.01 in a dominant model, respectively). In haplotype analysis, ht2 (T‐G‐T) and ht1 (C‐A‐C) were found to be in significant association with the clearance of HBV. However, no significant association was observed between miR‐219‐1 polymorphism and the risk of HCC occurrence. This result suggests that polymorphisms in the pri‐miRNA region of miR‐219‐1 might be a genetic factor for HBV clearance after infection. J. Med. Virol. 85:808–814, 2013. © 2013 Wiley Periodicals, Inc.
Repeatability of gait analysis for measuring knee osteoarthritis pain in patients with severe chronic pain
Authors: Asay Jessica L. , Boyer Katherine A. , Andriacchi Thomas P. 
Published: March 2013

AbstractGait measures are receiving increased attention in the evaluation of patients with knee osteoarthritis (OA). Yet, there remains a need to assess variability of gait analysis in patients with knee osteoarthritis over time and how pain affects variation in these gait parameters. The purpose of this study was to determine if important gait parameters, such as the knee adduction moment, knee flexion moment, peak vertical ground reaction force, and speed, were repeatable in patients with mild‐to‐moderate knee OA over a trial period of 12 weeks. Six patients were enrolled in this cross‐over study design after meeting strict inclusion criteria. Gait tests were conducted three times at 4 week intervals and once after the placebo arm of a randomized treatment sequence; each gait test followed a 2‐week period of receiving a placebo for a pain modifying drug. Repeatability for each gait variable was found using intraclass correlation coefficients (ICC) with a two‐way random model. This study found that the knee adduction moment was repeatable throughout the four gait tests. However, normalized peak vertical ground reaction force and knee flexion moment were not as repeatable, varying with pain. This suggests that these gait outcomes could offer a more objective way to measure a patient's level of pain. © 2012 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1007–1012, 2013
Use of chiral derivatization for the determination of dichlorprop in tea samples by ultra performance LC with fluorescence detection
Authors: Inoue Koichi , Prayoonhan Nuntawat , Tsutsui Haruhito , Sakamoto Tasuku , Nishimura Maiko , Toyo'oka Toshimasa 
Published: March 2013

Dichlorprop is available for agricultural use as a chiral pesticide. In this study, the stereoselective determination of dichlorprop enantiomers in tea samples such as green, black, jasmine, and oolong was developed by ultra performance LC with fluorescence spectrometry after covalent chiral derivatization. The separation was achieved on an Acquity BEH C18 column with the mobile phase consisting of 0.1% formic acid in acetonitrile/water at a flow rate of 0.4 mL/min. In the covalent chiral derivatization using (S)‐(+)‐4‐(N,N‐dimethylaminosulfonyl)‐7‐(3‐aminopyrrolidin‐1‐yl)‐2,1,3‐benzoxadiazole, the peak resolution between the S and R‐dichlorprop enantiomers was 2.6. LODs and LOQs values were 10 and 50 ng/mL standard solution. The linearity of the calibration curves yielded the coefficients (r2 > 0.99, ranging from 0.05 to 5 μg/mL) of determination of each of the dichlorprop enantiomers. SPE extraction was used for the sample preparation of dichlorprop in various tea samples. Recoveries were in the range of 82.4–97.6% with associated precision values (within‐day: 82.4–95.8%, n = 6, and between‐day: 83.7–97.6% for 3 days) for repeatability and reproducibility. Based on this result, our method has been proven to be highly efficient and suitable for the routine assay of dichlorprop enantiomers in various tea samples. We propose that the ultra performance LC assay after covalent chiral derivatization would be the renewed tools in the era of chiral stationary platform for chiral pesticide residues in foods.
Photodynamic inactivation of chlorin e6‐loaded CTAB‐liposomes against Candida albicans
Authors: Yang Yu‐Tsai , Chien Hsiung‐Fei , Chang Po‐Han , Chen Yee‐Chun , Jay Michael , Tsai Tsuimin , Chen Chin‐Tin 
Published: March 2013

AbstractBackground and ObjectivesAntimicrobial photodynamic inactivation (PDI) is a promising therapeutic modality for the treatment of local infections. To increase the efficacy of PDI, chlorine e6 (Ce6) was encapsulated in cationic CTAB‐liposomes composed of various ratios of dimyristoyl‐sn‐glycero‐phosphatidylcholine (DMPC) and the cationic surfactant, cetyltrimethyl ammonium bromide (CTAB). The PDI efficacy of the liposomal‐Ce6 was assessed in vitro against susceptible and drug‐resistant clinical isolates of Candida albicans (C. albicans) as well as in infected burn wounds.Study Design/Materials and MethodsCe6 was encapsulated in CTAB‐liposomes by the film hydration method. Particle size distribution and zeta potential of the cationic liposomes were measured using a Zetasizer Nano‐ZS. UV‐visible spectra were used to measure lipid/Ce6 (L/C) ratio and drug entrapment efficiency while differential scanning calorimetry (DSC) was used to study the thermotropic behavior of DMPC liposomes upon CTAB addition. In vivo PDI efficacy was carried out in an infected burn wound using a rat model.ResultsThe increase in zeta potential and a shift in the phase transition temperature (Tm) upon CTAB addition confirmed its entrapment within the lipid bilayers of the liposome. Meanwhile, the CTAB addition did not affect the Ce6 entrapment efficiency and physical attributes of the liposomes. In vitro studies showed that the PDI effect of the Ce6‐loaded CTAB‐liposomes was dependent on the lipid to Ce6 molar ratio (L/C), particle size and the concentration of CTAB in the liposomes. The lower L/C ratio and smaller liposomes exerted significantly higher PDI effects. In addition, an increase in the CTAB to lipid ratio led to a significant increase in the PDI effect of Ce6 against susceptible and drug‐resistant clinical isolates of C. albicans after light illumination.ConclusionsOur results indicate that a low L/C ratio, high positive charge, and small particle size of CTAB‐liposomes significantly enhances their PDI efficacy against C. albicans. Lasers Surg. Med. 45: 175–185, 2013. © 2013 Wiley Periodicals, Inc.
Non‐Natural Amino Acids for Protein Engineering and New Protein Chemistries
Authors: Kwon Inchan , Lim Sung In 
Published: March 2013

AbstractNon‐natural amino acids can be used to expand the protein sequence space significantly beyond the limits set by nature. Expanding the protein sequence space opens a new door to engineering and chemically modifying proteins. Reassigning codons to non‐natural amino acids as well as engineering protein translational machinery is required to incorporate non‐natural amino acids into a single or multiple sites of a target protein in cells. Non‐natural amino acid incorporation holds a great promise in substantially improving protein intrinsic properties and providing new orthogonal chemistries to proteins for bioconjugation.magnified image
High‐Efficiency Preparation of Macrocyclic Polymers via a Circulatory Extraction–Cyclization Strategy
Authors: Zhu Xing , Zhou Nianchen , Zhu Jian , Zhang Zhengbiao , Zhang Wei , Cheng Zhenping , Tu Yingfeng , Zhu Xiulin 
Published: March 2013

AbstractTypically, intramolecular cyclization reactions need to be conducted at high dilution to avoid interchain coupling, which leads to the production of cyclic polymer at an extremely low output. Herein, a high‐efficiency Cu‐catalyzed azide/alkyne cycloaddition “click” synthesis of cyclic polystyrene (PS) and cyclic poly (methyl methacrylate) (PMMA) is reported via a circulatory technique of evaporation–condensation–extraction–inflow strategy by the utilization of elaborately designed equipment. High‐output cyclic PS (one batch, 0.71 g cyclic polymer from 1.0 g linear polymer loading) and cyclic PMMA (one batch, 0.62 g cyclic PMMA from 1.0 g linear polymer loading) are achieved. This promising preparation should be beneficial to the large‐scale application and research of cyclic polymers.magnified image
Hetero Diels–Alder Chemistry for the Functionalization of Single‐Walled Carbon Nanotubes with Cyclopentadienyl End‐Capped Polymer Strands
Authors: Zydziak Nicolas , Preuss Corinna M. , Winkler Volker , Bruns Michael , Hübner Christof , Barner‐Kowollik Christopher 
Published: March 2013

AbstractSingle‐walled carbon nanotubes (SWCNTs) are pre‐functionalized with a pyridinyl‐based dithioester to undergo a hetero Diels–Alder (HDA) reaction with cyclopentadienyl end‐capped poly(methyl)methacrylate (Mn = 2700 g mol−1, PDI = 1.14). Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis (EA), and X‐ray photoelectron spectroscopy (XPS) evidence the success of the grafting process. The estimated resulting grafting density (from XPS and EA) via the HDA reaction increases by a factor of more than two (0.0774 chains·nm−2 via XPS) compared with typical values obtained via a direct cyclopentadiene driven Diels–Alder conjugation onto non‐functional SWCNTs under similar conditions.
magnified image
Expression of Fap amyloids in Pseudomonas aeruginosa,P. fluorescens, and P. putida results in aggregation and increased biofilm formation
Authors: Dueholm Morten S. , Søndergaard Mads T. , Nilsson Martin , Christiansen Gunna , Stensballe Allan , Overgaard Michael T. , Givskov Michael , Tolker‐Nielsen Tim , Otzen Daniel E. , Nielsen Per H. 
Published: March 2013

AbstractThe fap operon, encoding functional amyloids in Pseudomonas (Fap), is present in most pseudomonads, but so far the expression and importance for biofilm formation has only been investigated for P. fluorescens strain UK4. In this study, we demonstrate the capacity of P. aeruginosa PAO1, P. fluorescens Pf‐5, and P. putida F1 to express Fap fibrils, and investigated the effect of Fap expression on aggregation and biofilm formation. The fap operon in all three Pseudomonas species conferred the ability to express Fap fibrils as shown using a recombinant approach. This Fap overexpression consistently resulted in highly aggregative phenotypes and in increased biofilm formation. Detailed biophysical investigations of purified fibrils confirmed FapC as the main fibril monomer and supported the role of FapB as a minor, nucleating constituent as also indicated by bioinformatic analysis. Bioinformatics analysis suggested FapF and FapD as a potential β‐barrel membrane pore and protease, respectively. Manipulation of the fap operon showed that FapA affects monomer composition of the final amyloid fibril, and that FapB is an amyloid protein, probably a nucleator for FapC polymerization. Our study highlights the fap operon as a molecular machine for functional amyloid formation.
Sparse BLIP: BLind Iterative Parallel imaging reconstruction using compressed sensing
Authors: She Huajun , Chen Rong‐Rong , Liang Dong , DiBella Edward V. R. , Ying Leslie 
Published: March 2013

PurposeTo develop a sensitivity‐based parallel imaging reconstruction method to reconstruct iteratively both the coil sensitivities and MR image simultaneously based on their prior information.MethodsParallel magnetic resonance imaging reconstruction problem can be formulated as a multichannel sampling problem where solutions are sought analytically. However, the channel functions given by the coil sensitivities in parallel imaging are not known exactly and the estimation error usually leads to artifacts. In this study, we propose a new reconstruction algorithm, termed Sparse BLind Iterative Parallel, for blind iterative parallel imaging reconstruction using compressed sensing. The proposed algorithm reconstructs both the sensitivity functions and the image simultaneously from undersampled data. It enforces the sparseness constraint in the image as done in compressed sensing, but is different from compressed sensing in that the sensing matrix is unknown and additional constraint is enforced on the sensitivities as well. Both phantom and in vivo imaging experiments were carried out with retrospective undersampling to evaluate the performance of the proposed method.ResultsExperiments show improvement in Sparse BLind Iterative Parallel reconstruction when compared with Sparse SENSE, JSENSE, IRGN‐TV, and L1‐SPIRiT reconstructions with the same number of measurements.ConclusionThe proposed Sparse BLind Iterative Parallel algorithm reduces the reconstruction errors when compared to the state‐of‐the‐art parallel imaging methods. Magn Reson Med 71:645–660, 2014. © 2013 Wiley Periodicals, Inc.
Protein misfolding in the late‐onset neurodegenerative diseases: Common themes and the unique case of amyotrophic lateral sclerosis
Authors: Mulligan Vikram Khipple , Chakrabartty Avijit 
Published: March 2013

ABSTRACTEnormous strides have been made in the last 100 years to extend human life expectancy and to combat the major infectious diseases. Today, the major challenges for medical science are age‐related diseases, including cancer, heart disease, lung disease, renal disease, and late‐onset neurodegenerative disease. Of these, only the neurodegenerative diseases represent a class of disease so poorly understood that no general strategies for prevention or treatment exist. These diseases, which include Alzheimer's disease, Parkinson's disease, Huntington's disease, the transmissible spongiform encephalopathies, and amyotrophic lateral sclerosis (ALS), are generally fatal and incurable. The first section of this review summarizes the diversity and common features of the late‐onset neurodegenerative diseases, with a particular focus on protein misfolding and aggregation—a recurring theme in the molecular pathology. The second section focuses on the particular case of ALS, a late‐onset neurodegenerative disease characterized by the death of central nervous system motor neurons, leading to paralysis and patient death. Of the 10% of ALS cases that show familial inheritance (familial ALS), the largest subset is caused by mutations in the SOD1 gene, encoding the Cu, Zn superoxide dismutase (SOD1). The unusual kinetic stability of SOD1 has provided a unique opportunity for detailed structural characterization of conformational states potentially involved in SOD1‐associated ALS. This review discusses past studies exploring the stability, folding, and misfolding behavior of SOD1, as well as the therapeutic possibilities of using detailed knowledge of misfolding pathways to target the molecular mechanisms underlying ALS and other neurodegenerative diseases. Proteins 2013; 81:1285–1303. © 2013 Wiley Periodicals, Inc.
Structural and functional analyses of catalytic domain of GH10 xylanase from Thermoanaerobacterium saccharolyticum JW/SL‐YS485
Authors: Han Xu , Gao Jian , Shang Na , Huang Chun‐Hsiang , Ko Tzu‐Ping , Chen Chun‐Chi , Chan Hsiu‐Chien , Cheng Ya‐Shan , Zhu Zhen , Wiegel Juergen , Luo Wenhua , Guo Rey‐Ting , Ma Yanhe 
Published: March 2013

ABSTRACTXylanases are capable of decomposing xylans, the major components in plant cell wall, and releasing the constituent sugars for further applications. Because xylanase is widely used in various manufacturing processes, high specific activity, and thermostability are desirable. Here, the wild‐type and mutant (E146A and E251A) catalytic domain of xylanase from Thermoanaerobacterium saccharolyticum JW/SL‐YS485 (TsXylA) were expressed in Escherichia coli and purified subsequently. The recombinant protein showed optimal temperature and pH of 75°C and 6.5, respectively, and it remained fully active even after heat treatment at 75°C for 1 h. Furthermore, the crystal structures of apo‐form wild‐type TsXylA and the xylobiose‐, xylotriose‐, and xylotetraose‐bound E146A and E251A mutants were solved by X‐ray diffraction to high resolution (1.32–1.66 Å). The protein forms a classic (β/α)8 folding of typical GH10 xylanases. The ligands in substrate‐binding groove as well as the interactions between sugars and active‐site residues were clearly elucidated by analyzing the complex structures. According to the structural analyses, TsXylA utilizes a double displacement catalytic machinery to carry out the enzymatic reactions. In conclusion, TsXylA is effective under industrially favored conditions, and our findings provide fundamental knowledge which may contribute to further enhancement of the enzyme performance through molecular engineering. Proteins 2013; 81:1256–1265. © 2013 Wiley Periodicals, Inc.
Routine fabrication of reduced graphene oxide microarray devices via all solution processing
Authors: Lanche Ruben , Delle Lotta E. , Weil Maryam , Vu Xuan Thang , Pachauri Vivek , Munief Walid M. , Wagner Patrick , Ingebrandt Sven 
Published: March 2013

AbstractA method for the routine fabrication of graphene (reduced graphene oxide (r‐GO)) based devices is reported. We describe a solution‐based technique for the fabrication of the devices on alternative substrates and subsequent on‐substrate processing of graphene oxide into reduced graphene oxide. As sensor platform we mainly used interdigitated gold electrodes forming microarray structures on glass substrates. Graphene oxide was site‐specifically deposited onto microelectrode arrays by dielectrophoresis followed by a solution‐based reduction of graphene oxide with L‐ascorbic acid. In order to test the r‐GO sensor stability and performance, impedance spectroscopy was used. The optimized all solution processed fabrication provides an attractive fabrication route for robust r‐GO microarray devices in a flexible, scalable and cost‐effective approach. Schematics for a microarray chip based on reduced graphene oxide.
Spectroscopic studies of Tm‐doped zirconia nanoparticles
Authors: Soares M. R. N. , Rino L. , Costa F. M. , Monteiro T. 
Published: March 2013

AbstractIntra‐4f12 transitions of Tm3+ ions in zirconia powders processed by solution combustion synthesis (CS) were studied by optical techniques. The results were compared with the ones obtained in reference samples of yttria stabilized zirconia fibers grown by laser floating zone. The spectroscopic features observed for the tetragonal fibre were compared with the Stark lines detected in the polyphasic (monoclinic and tetragonal) powder suggesting additional Tm3+ sites/environments due to the ions in the monoclinic host. The stability of the blue 1D2 → 3F4 and red 1G4 → 3H6 transitions was found to be strongly dependent on temperature. For the fibres, the blue luminescence increases by a factor of two between 15 K and the room temperature when pumping the sample in the 1D2 level. When the excitation is performed in the 1G4 state a higher stability of the red luminescence was found to occur in fibres than in the polyphasic powder. Constant 1G4 → 3H6 integrated intensity was observed in the fibres, while a decrease of the red luminescence efficiency occurs with temperature for the polyphasic powder. The suppression of the nonradiative paths which compete with the radiative transition could be attained by using thulium doped yttria stabilized CS powders.
Modelling escape and capture processes in GaInNAs quantum well solar cells
Authors: Kengradomying O. , Jiang S. , Wang Q. , Vogiatzis N. , Rorison J. M. 
Published: March 2013

AbstractCarrier escape and capture processes in a GaInA/GaAs quantum well (QW) and a GaInNAs/GaAs QW are compared through modelling using a rate equation approach. QW compositions corresponding to bandgaps of 0.983 eV, 1.000 eV and 1.100 eV are considered for applications in solar cells. For GaInAs a standard alloy model is used, including strain effects, while for GaInNAs the Band Anticrossing (BAC) model is used. The roles of 1. the conduction band QW barrier height and 2. the corresponding effective mass in affecting the electron escape and capture in the QW are considered in detail. The contribution of photogenerated currents from the barrier and QW are considered. The effect of QW depth is found to be larger than changes in the electron effective mass. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nitrogen incorporation into GaAsN and InGaAsN layers grown by liquid‐phase epitaxy
Authors: Milanova Malina , Vitanov Petko , Terziyska Penka , Koleva Greta , Popov Georgy 
Published: March 2013

AbstractThis paper presents the comparison of nitrogen incorporation in GaAsN and InGaAsN layers grown on GaAs substrate from Ga‐ and In‐rich solution, respectively, by liquid‐phase epitaxy. Polycrystalline GaN has been used as a source of nitrogen in two cases. The initial epitaxy temperature has been varied in the temperature range 600‐550 °C. Nitrogen content in Ga1‐xAsNx grown layers has been determined to be in the range 0.1‐0.5%. Higher nitrogen incorporation efficiency has been found for quaternary InGaAsN layers grown under carefully chosen lattice matched conditions. The incorporation of nitrogen into GaAsN and InGaAsN layers has been study by vibrational mode absorption spectroscopy. Nitrogen‐induced vibration mode near 472 cm‐1 has been registered in GaAsN samples. Preferential In‐N bonds and the formation of N‐centred In3Ga1 clusters have been identified for lattice matched to GaAs epitaxial InGaAsN layers. Electrical properties of the samples have been characterized by temperature‐dependent Hall effect measurements. Nominally undoped GaAsN and InGaAsN grown layers are n‐type with Hall concentration about one order of magnitude higher in comparison to layers not containing nitrogen. Thermally activated increase in the free carrier concentration at temperatures higher than 150 K is observed which indicates the presence of N‐related deep donor levels below dilute nitride conduction band edge. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improved control of the phosphorous surface concentration during in‐line diffusion of c‐Si solar cells by APCVD
Authors: Davis Kristopher O. , Jiang Kaiyun , Demberger Carsten , Zunft Heiko , Haverkamp Helge , Habermann Dirk , Schoenfeld Winston V. 
Published: March 2013

AbstractEmitter formation for industrial crystalline silicon (c‐Si) solar cells is demonstrated by the deposition of phosphorous‐doped silicate glasses (PSG) on p‐type monocrystalline silicon wafers via in‐line atmospheric pressure chemical vapor deposition (APCVD) and subsequent thermal diffusion. Processed wafers with and without the PSG layers have been analysed by SIMS measurements to investigate the depth profiles of the resultant phosphorous emitters. Subsequently, complete solar cells were fabricated using the phosphorous emitters formed by doped silicate glasses to determine the impact of this high‐throughput doping method on cell performance. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)