bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of pH‐sensitive hydrogels to control the permeability anisotropy of oil reservoirs
Authors: Garcia Cordeiro Tessarolli Fernanda , Gomes De Carvalho Queirós Yure , Regina Elias Mansur Claudia 
Published: March 2014

ABSTRACTIn stratified or fractured oil reservoirs, the oil recovery efficiency tends to be low as the injected fluid flows mainly through the matrix's most permeable regions, leaving behind part of the displaceable oil in the matrix's unswept zones. Given this issue, this study aims to evaluate the potential of applying seven commercial samples, based on poly(acrylic acid), to control the anisotropic permeability profile of reservoirs. To perform this study, first, continuous and oscillatory shear tests were conducted to characterize the hydrogel's rheological and viscoelastic behavior in various subsurface conditions (salinity, temperature, and/or pH value). Second, polymer dispersion elution tests were performed in a porous medium to evaluate the matrix's permeability reduction after treatment with hydrogels. The seven commercial samples were classified as pseudoplastic fluids at pH values ranging from 1 to 10. Under typical reservoir conditions, PAAr 70 (which has intermediate molar mass and intermediate number of crosslinks) was the only sample to behave as a strong gel (G′/G″ > 10). Elution tests confirmed that the PAAr 70 hydrogel gelified inside the consolidated sandstone plugs and reduced the matrix's permeability four‐fold. Therefore, samples based on poly(acrylic acid) with high crosslink density proved to be the most promising for controlling the anisotropic permeability profile of heterogeneous oil reservoirs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40665.
Optorheological thickening under the pulsed laser photocrosslinking of a polymer
Authors: Okoniewski Stephen Richard , Wisniewski Danielle , Frazer N. Laszlo , Mu Weiqiang , Arceo Andrew , Rathi Pranjali , Ketterson J. B. 
Published: March 2014

ABSTRACTElectro‐, magneto‐, and other rheological effects can be used to externally control fluid viscosity. However, they are largely reversible and in addition subject to colloidal settling, electrostatic breakdown, or high cost. In the experiments described here the dependence of the viscosity of a polymer solution under pulsed laser photocrosslinking as a function of radiation dose is determined using the Brownian motion of colloidal polystyrene tracers that were optically confined to a one dimensional channel. The system studied was a transparent aqueous solution of poly(ethylene glycol) dimethacrylate together with a 1‐hydroxycyclohexyl phenyl ketone photoinitiator. An increase in the viscosity of the solution with the laser fluence was observed. The growth was exponential, stable between pulses, and spanned nearly three orders of magnitude. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40690.
The mechanical properties of β‐Si3N4 whiskers‐reinforced dental resin composites
Authors: Zuo Kai‐Hui , Lu Li‐Min , Zeng Yu‐Ping 
Published: March 2014

ABSTRACTThe surface‐modified β‐Si3N4 whiskers were used as inorganic fillers to reinforce dental resin (Bis‐GMA/TEGDMA) matrix with filler level ranging from 0 to 60 wt %. The experimental results indicated that the fracture strength of the composites increased from 79.85 to 139.8 MPa with increasing the whiskers loading. The compressive strength, elastic modulus, and rockwell hardness all increased monotonously with increasing filler level. Furthermore, thermal cycling did not decrease the fracture strength of the composites. Moreover, the composites showed good biocompatibility to support MG63 cells adhesion and proliferation. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40692.
Fullerene Sugar Balls: A New Class of Biologically Active Fullerene Derivatives
Authors: Nierengarten Iwona , Nierengarten Jean‐François 
Published: March 2014

AbstractAmong the large variety of bioactive C60 derivatives, fullerene derivatives substituted with sugar residues, that is, glycofullerenes, are of particular interest. The sugar residues are not only solubilizing groups; their intrinsic biological properties also provide additional appealing features to the conjugates. The most recent advances in the synthesis and the biological applications of glycofullerenes are summarized in the present review article with special emphasis on globular glycofullerenes, that is, fullerene sugar balls, constructed on a hexa‐substituted fullerene scaffold. The high local concentration of carbohydrates around the C60 core in fullerene sugar balls is perfectly suited to the binding of lectins through the “glycoside cluster effect”, and these compounds are potential anti‐adhesive agents against bacterial infection. Moreover, mannosylated fullerene sugar balls have shown antiviral activity in an Ebola pseudotyped infection model. Finally, when substituted with peripheral iminosugars, dramatic multivalent effects have been observed for glycosidase inhibition. These unexpected observations have been rationalized by the interplay of interactions involving the catalytic site of the enzyme and non‐glycone binding sites with lectin‐like abilities.
Optimization of pH values to formulate the bireagent kit for serum uric acid assay
Authors: Huang Ya , Chen Yuanxiang , Yang Xiaolan , Zhao Hua , Hu Xiaolei , Pu Jun , Liao Juan , Long Gaobo , Liao Fei 
Published: March 2014

AbstractA new formulation of the bireagent kit for serum uric acid assay was developed based on the effects of pH on enzyme stability. At 4 °C, half‐lives of uricases from Bacillus fastidious and Arthrobacter globiforms were longer than 15 months at pH 9.2, but became shorter at pH below 8.0; half‐lives of ascorbate oxidase and peroxidase were comparable at pH 6.5 and 7.0, but became much shorter at pH higher than 7.4. In the new formulation of the bireagent kit, Reagent A contained peroxidase, 4‐aminoantipyrine, and ascorbate oxidase in 50 mM phosphate buffer at pH 6.5; Reagent B contained B. fastidious or A. globiforms uricase in 50 mM sodium borate buffer at pH 9.2; Reagents A and B were mixed at 4:1 to produce a final pH from 7.2 to 7.6 for developing a stable color. The new bireagent kit consumed smaller quantities of three enzymes for the same shelf life. With the new bireagent kit, there were linear responses of absorbance at 546 nm to uric acid up to 34 mM in reaction mixtures and a good correlation of uric acid levels in clinical sera with those by a commercial kit, but stronger resistance to ascorbate. Therefore, the new formulation was advantageous.
Interleukin‐7 receptor‐α gene mutations are not detected in adult T‐cell acute lymphoblastic leukemia
Authors: Rozovski Uri , Li Ping , Harris David , Ohanian Maro , Kantarjian Hagop , Estrov Zeev 
Published: March 2014

AbstractSomatic mutations in cancer cell genes are classified according to their functional significance. Those that provide the malignant cells with significant advantage are collectively referred to as driver mutations and those that do not, are the passenger mutations. Accordingly, analytical criteria to distinguish driver mutations from passenger mutations have been recently suggested. Recent studies revealed mutations in interleukin‐7 receptor‐α (IL7R) gene in 10% of pediatric T‐cell acute lymphoblastic leukemia (T‐ALL) patients and in only a few cases of pediatric B‐ALL. IL7R mutations are also frequently found in patients with lung cancer, but whereas in pediatric T‐ALL IL7R mutations are “drivers” (consisting of gain‐of‐function mutations within a narrow 50‐base pair interval at exon 6 that confer cytokine‐independent cell growth and promote tumor transformation), in lung cancer, mutations are substitution mutations randomly distributed across the gene and are probably only “passenger” events. Because the treatment response of adult T‐ALL is significantly poorer than that of childhood T‐ALL and because exon 6 IL7R mutations play a role in the pathogenesis of childhood T‐ALL, we sought to determine how the pattern of IL7R mutations varies between adult and childhood T‐ALL. To that end, we sequenced the 50‐base pair interval in exon 6 of the IL7R of DNA obtained from bone marrow samples of 35 randomly selected adult patients with T‐ALL. Our analysis revealed that none of these 35 samples carried an IL7R mutation in exon 6. Whether differences in the genetic makeup of adult and childhood T‐ALL explain the differential response to therapy remains to be determined.
Production of Macrocyclic Sesqui‐ and Diterpenes in Heterologous Microbial Hosts: A Systems Approach to Harness Nature’s Molecular Diversity
Authors: Brück Thomas , Kourist Robert , Loll Bernhard 
Published: March 2014

AbstractMacrocyclic sesqui‐ (C15) and diterpenes (C20) are a functionally diverse group of natural products with versatile bioactivities encompassing anticancer, antimicrobial and insecticidal agents. Structural complexity prevents economically efficient total synthesis of these higher terpenoids. Heterologous production in recombinant whole‐cell biocatalysts is an emerging alternative. Conventional cell systems (i.e., Escherichia coli and Saccharomyces cerevisiae) frequently suffer from low volumetric yields. However, recent combinations of metabolic, enzyme and process engineering in conjunction with systems biology allow significant improvements towards economically viable processes. This Review analyzes research trends in the dynamic fields of terpene‐centered microbial cell systems and enzyme engineering. An outlook is given on emerging microbial hosts, which may simplify cellular engineering towards higher product titers.
Shielding of a Microdisc Electrode Surrounded by an Adsorbing Surface
Authors: Eloul Shaltiel , Compton Richard G. 
Published: March 2014

AbstractMicrodisc electrodes are usually made by surrounding a metal wire with a diameter of a few microns in a flat insulating sheath made of glass or another insulating material. The sheath is generally assumed to play no role in the voltammetry at the microdisc electrode. However, in some cases, and especially for experiments with nanoparticles, significant adsorption can occur onto the sheath, perturbing the current response measured at the disc. We report theoretical calculations of the effect of shielding by the insulating sheath of microelectrodes and show that it can significantly influence the magnitude of the current, even for relatively small levels of adsorption, not least because of the typically very large area of the insulation relative to the electrode size. Working curves are provided to permit the analysis of experimental data.
Regiospecific Coordination of Re3 Clusters with the Sumanene‐Type Hexagons on Endohedral Metallofullerenes and Higher Fullerenes That Provides an Efficient Separation Method
Authors: Chen Chia‐Hsiang , Lin Dong‐Yui , Yeh Wen‐Yann 
Published: March 2014

AbstractThe reactions of [(μ‐H)3Re3(CO)11(NCMe)] with Sc2@C82‐C3v(8), Sc2C2@C80‐C2v(5), Sc2O@C82‐Cs(6), C86‐C2(17), and C86‐Cs(16) have been carried out to produce face‐capping cluster complexes. The Re3 triangles are found to bind to the sumanene‐type hexagons on the fullerene surface regiospecifically. In contrast, Sc3N@C78‐D3h(5) and Sc3N@C80‐Ih show no reactivity toward [(μ‐H)3Re3(CO)11(NCMe)], probably due to electronic and steric factors. These complexes can be easily purified by using HPLC. Carbonylation of each complex releases the corresponding higher fullerene or endohedral metallofullerene in pure form. Remarkably, the C86‐C2(17) and C86‐Cs(16) isomers were successively separated through Re3 cluster complexation/decomplexation. This unique bonding feature may provide an attractive general strategy to purify as yet unresolved fullerene mixtures.
TiO2 Nanospheres: A Facile Size‐Tunable Synthesis and Effective Light‐Harvesting Layer for Dye‐Sensitized Solar Cells
Authors: Wang Shuan , Ding Yong , Xu Sichao , Zhang Yunxia , Li Guanghai , Hu Linhua , Dai Songyuan 
Published: March 2014

AbstractA facile route to synthesize amorphous TiO2 nanospheres by a controlled oxidation and hydrolysis process without any structure‐directing agents or templates is presented. The size of the amorphous TiO2 nanospheres can be easily turned from 20 to 1500 nm by adjusting either the Ti species or ethanol content in the reaction solution. The phase structure of nanospheres can be controlled by hydrothermal treatment. The TiO2 nanospheres show excellent size‐dependent light‐scattering effects and can be structured into a light‐harvesting layer for dye‐sensitized solar cells with a quite high power conversion efficiency of 9.25 %.
Selenoquinones Stabilized by Ruthenium(II) Arene Complexes: Synthesis, Structure, and Cytotoxicity
Authors: Dubarle‐Offner Julien , Clavel Catherine M. , Gontard Geoffrey , Dyson Paul J. , Amouri Hani 
Published: March 2014

AbstractA new series of monoselenoquinone and diselenoquinone π complexes, [(η6‐p‐cymene)Ru(η4‐C6R4SeE)] (R=H, E=Se (6); R=CH3, E=Se (7); R=H, E=O (8)), as well as selenolate π complexes [(η6‐p‐cymene)Ru(η5‐C6H3R2Se)][SbF6] (R=H (9); R=CH3 (10)), stabilized by arene ruthenium moieties were prepared in good yields through nucleophilic substitution reactions from dichlorinated‐arene and hydroxymonochlorinated‐arene ruthenium complexes [(η6‐p‐cymene)Ru(C6R4XCl)][SbF6]2 (R=H, X=Cl (1); R=CH3, X=Cl (2); R=H, X=OH (3)) as well as the monochlorinated π complexes [(η6‐p‐cymene)Ru(η5‐C6H3R2Cl)][SbF6]2 (R=H (4); R=CH3 (5)). The X‐ray crystallographic structures of two of the compounds, [(η6‐p‐cymene)Ru(η4‐C6Me4Se2)] (7) and [(η6‐p‐cymene)Ru(η4‐C6H4SeO)] (8), were determined. The structures confirm the identity of the target compounds and ascertain the coordination mode of these unprecedented ruthenium π complexes of selenoquinones. Furthermore, these new compounds display relevant cytotoxic properties towards human ovarian cancer cells.
Rhodium‐Catalyzed Direct Amination of Arenes with Nitrosobenzenes: A New Route to Diarylamines
Authors: Du Juanjuan , Yang Yaxi , Feng Huijin , Li Yuanchao , Zhou Bing 
Published: March 2014

AbstractA RhIII‐catalyzed addition of aryl CH bonds to nitrosobenzenes, followed by cleavage of the resulting hydroxylamines in situ, has been reported. Different directing groups, such as N‐based heterocycles and ketoximes, can be used in this CH amination process, providing valuable diarylamines in excellent yields. Most importantly, this process provides a new method for attaching arylamine groups to aromatic rings.
Long Noncoding RNAs: Emerging Stars in Gene Regulation, Epigenetics and Human Disease
Authors: Bhan Arunoday , Mandal Subhrangsu S. 
Published: March 2014

AbstractNoncoding RNAs (ncRNAs) are classes of transcripts that are encoded by the genome and transcribed but never get translated into proteins. Though not translated into proteins, ncRNAs play pivotal roles in a variety of cellular functions. Here, we review the functions of long noncoding RNAs (lncRNAs) and their implications in various human diseases. Increasing numbers of studies demonstrate that lncRNAs play critical roles in regulation of protein‐coding genes, maintenance of genomic integrity, dosage compensation, genomic imprinting, mRNA processing, cell differentiation, and development. Misregulation of lncRNAs is associated with a variety of human diseases, including cancer, immune and neurological disorders. Different classes of lncRNAs, their functions, mechanisms of action, and associations with different human diseases are summarized in detail, highlighting their as yet untapped potential in therapy.
1‐(1H‐Indol‐3‐yl)ethanamine Derivatives as Potent Staphylococcus aureus NorA Efflux Pump Inhibitors
Authors: Hequet Arnaud , Burchak Olga N. , Jeanty Matthieu , Guinchard Xavier , Le Pihive Emmanuelle , Maigre Laure , Bouhours Pascale , Schneider Dominique , Maurin Max , Paris Jean‐Marc , Denis Jean‐Noël , Jolivalt Claude 
Published: March 2014

AbstractThe synthesis of 37 1‐(1H‐indol‐3‐yl)ethanamine derivatives, including 12 new compounds, was achieved through a series of simple and efficient chemical modifications. These indole derivatives displayed modest or no intrinsic anti‐staphylococcal activity. By contrast, several of the compounds restored, in a concentration‐dependent manner, the antibacterial activity of ciprofloxacin against Staphylococcus aureus strains that were resistant to fluoroquinolones due to overexpression of the NorA efflux pump. Structure–activity relationships studies revealed that the indolic aldonitrones halogenated at position 5 of the indole core were the most efficient inhibitors of the S. aureus NorA efflux pump. Among the compounds, (Z)‐N‐benzylidene‐2‐(tert‐butoxycarbonylamino)‐1‐(5‐iodo‐1H‐indol‐3‐yl)ethanamine oxide led to a fourfold decrease of the ciprofloxacin minimum inhibitory concentration against the SA‐1199B strain when used at a concentration of 0.5 mg L−1. To the best of our knowledge, this activity is the highest reported to date for an indolic NorA inhibitor. In addition, a new antibacterial compound, tert‐butyl (2‐(3‐hydroxyureido)‐2‐(1H‐indol‐3‐yl)ethyl)carbamate, which is not toxic for human cells, was also found.
A randomized, open‐label clinical trial of tasisulam sodium versus paclitaxel as second‐line treatment in patients with metastatic melanoma
Authors: Hamid Omid , Ilaria Robert , Garbe Claus , Wolter Pascal , Maio Michele , Hutson Thomas E. , Arance Ana , Lorigan Paul , Lee Jeeyun , Hauschild Axel , Mohr Peter , Hahka‐Kemppinen Marjo , Kaiser Christopher , Turner P. Kellie , Conti Ilaria , Grob Jean‐Jacques 
Published: March 2014

BACKGROUNDTasisulam sodium (hereafter referred to as tasisulam) is a novel, highly albumin‐bound agent that demonstrated activity in a phase 2 melanoma study.METHODSIn this open‐label phase 3 study, patients with AJCC stage IV melanoma received tasisulam (targeting an albumin‐corrected exposure of 1200‐6400 h (hour).μg/mL on day 1) or paclitaxel (80 mg/m2 on days 1, 8, and 15) every 28 days as second‐line treatment.RESULTSThe study was placed on clinical hold after randomization of 336 patients when a safety review indicated an imbalance of possibly drug‐related deaths in the tasisulam arm. Efficacy results for tasisulam versus paclitaxel revealed a response rate of 3.0% versus 4.8%, a median progression‐free survival of 1.94 months versus 2.14 months (P = .048), and a median overall survival of 6.77 months versus 9.36 months (P = .121). The most common drug‐related grade ≥3 laboratory toxicities (graded according to Common Terminology for Adverse Events [version 3.0]) were thrombocytopenia (18.9%) for patients treated with tasisulam and neutropenia/leukopenia (8.7%) among those receiving paclitaxel. There were 13 possibly related deaths reported to occur on the study, with the majority occurring during cycle 2 in the setting of grade 4 myelosuppression, all in the tasisulam arm. Investigation of the unexpectedly high rate of hematologic toxicity revealed a subset of patients with low tasisulam clearance, leading to drug accumulation and high albumin‐corrected exposure in cycle 2.CONCLUSIONSAlthough the study was stopped early because of safety issues in the tasisulam arm, tasisulam was considered unlikely to be superior to paclitaxel, and paclitaxel activity in the second‐line treatment of melanoma was much lower than expected. The toxicity imbalance was attributed to an unexpectedly low tasisulam clearance in a subset of patients, underscoring the importance of pharmacokinetic monitoring of compounds with complex dosing, even in late‐phase studies. Cancer 2014;120:2016–2024. © 2014 American Cancer Society.
Effect of adjuvant/neoadjuvant trastuzumab on clinical outcomes in patients with HER2‐positive metastatic breast cancer
Authors: Murthy Rashmi K. , Varma Ankur , Mishra Priyankana , Hess Kenneth R. , Young Elliana , Murray James L. , Koenig Kimberly H. , Moulder Stacy L. , Melhem‐Bertrandt Amal , Giordano Sharon H. , Booser Daniel , Valero Vicente , Hortobagyi Gabriel N. , Esteva Francisco J. 
Published: March 2014

BACKGROUNDThe purpose of the current study was to describe the outcomes of patients with human epidermal growth factor receptor 2 (HER2)‐overexpressed/amplified (HER2+) early breast cancer who received adjuvant or neoadjuvant trastuzumab‐based therapy and were subsequently retreated with trastuzumab for metastatic disease.METHODSA total of 353 patients with metastatic HER2+ breast cancer who were treated with trastuzumab as part of their first‐line treatment for metastatic disease were identified. A total of 75 patients had received adjuvant or neoadjuvant trastuzumab‐based therapy for early breast cancer, and 278 had not. Clinical outcomes of patients who had or had not received prior trastuzumab were compared using Cox proportional hazards regression and logistic regression analyses. Survival was estimated using the Kaplan‐Meier method.RESULTSThe clinical benefit (complete response, partial response, or stable disease of ≥ 6 months) rates were 71% in the group who did not receive prior trastuzumab and 39% in the group previously treated with trastuzumab. The adjusted odds ratios were 0.28 (95% confidence interval [95% CI], 0.13‐0.59; P = .0009) for clinical benefit rates and 0.39 (95% CI, 0.18‐0.82; P = .038) for objective (complete or partial) response rates. In the univariate analysis, the median overall survival rate was longer in the group who did not receive prior trastuzumab (36 months vs 28 months) (hazards ratio, 1.47; 95% CI, 1.07‐2.01 [P = .022]). The multivariate analysis found no significant difference in overall survival.CONCLUSIONSWhen treated with trastuzumab for metastatic disease, patients with HER2+ breast cancer without prior exposure to trastuzumab were found to have superior clinical outcomes to those with prior exposure. Prior trastuzumab exposure should be considered in treatment algorithms and in HER2‐targeted clinical trial enrollment for metastatic disease. Cancer 2014;120:1932–1938. © 2014 American Cancer Society.
Macroscopic Control of Helix Orientation in Films Dried from Cholesteric Liquid‐Crystalline Cellulose Nanocrystal Suspensions
Authors: Park Ji Hyun , Noh JungHyun , Schütz Christina , Salazar‐Alvarez German , Scalia Giusy , Bergström Lennart , Lagerwall Jan P. F. 
Published: March 2014

AbstractThe intrinsic ability of cellulose nanocrystals (CNCs) to self‐organize into films and bulk materials with helical order in a cholesteric liquid crystal is scientifically intriguing and potentially important for the production of renewable multifunctional materials with attractive optical properties. A major obstacle, however, has been the lack of control of helix direction, which results in a defect‐rich, mosaic‐like domain structure. Herein, a method for guiding the helix during film formation is introduced, which yields dramatically improved uniformity, as confirmed by using polarizing optical and scanning electron microscopy. By raising the CNC concentration in the initial suspension to the fully liquid crystalline range, a vertical helix orientation is promoted, as directed by the macroscopic phase boundaries. Further control of the helix orientation is achieved by subjecting the suspension to a circular shear flow during drying.