bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of mobile phase condition by using HCI program for extracting luteolin and apigenin from celery
Authors: Li Shengnan , Tian Minglei , Ho Row Kyung
Published: December 2010

An efficient optimization method was used to separate flavonoid compounds from celery by HCI program software. Two interfering species, tentatively considered the target compounds, were separated successfully by the HCI program with the optimum composition of mobile phase for reversed‐phase high performance liquid chromatography separation obtained. The elution profiles were calculated by the plate theory based on the linear and quadratic equations of the retention factor: lnk = lnkw + SF, k = A + B/F, lnk = L + MF + NF2, where F was the volume percentage of the organic modifier. In the binary solvents model, the calculated results of the mobile phase conditions suggested that methanol/water (60/40, v/v) or acetonitrile/water (34/66, v/v) was the optimized component, as was acetonitrile/methanol/water (10/30/60, v/v/v) when changed to a ternary solvents model. Under the experimental conditions, the agreement between the experimental elution profiles and the calculated values of the eluted concentration was relatively good. © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Improvement of photoluminescence of Cu+ ion in Li2SO4
Authors: Puppalwar S. P. , Dhoble S. J. , Kumar Animesh
Published: December 2010

The synthesis of the Li2SO4: Cu phosphor using a wet chemical method is reported here. The XRD technique showed the crystalline nature of the prepared material. The presence of Na and K in the host affected the observed photoluminescence characteristics of Li2SO4: Cu. Photoluminsecent emission spectra of Li2SO4: Cu phosphor showed a very strong prominet peak at 387 nm in the indigo region due to 3d9 4 s1 ↔ 3d10 transition of the Cu+ ion. The increase in peak intensity of the PL spectrum suggests that Cu+ acts as the luminescence center in the present matrix. Copyright © 2010 John Wiley & Sons, Ltd.
Quantification of receptor targeting aptamer binding characteristics using single‐molecule spectroscopy
Authors: Book Brittany , Chen Jiji , Irudayaraj Joseph
Published: December 2010

This experimental design presents a single molecule approach based on fluorescence correlation spectroscopy (FCS) for the quantification of outer membrane proteins which are receptors to an aptamer specifically designed to target the surface receptors of live Salmonella typhimurium. By using correlation analysis, we also show that it is possible to determine the associated binding kinetics of these aptamers on live single cells. Aptamers are specific oligonucleotides designed to recognize conserved sequences that bind to receptors with high affinity, and therefore can be integrated into selective biosensor platforms. In our experiments, aptamers were constructed to bind to outer membrane proteins of S. typhimurium and were assessed for specificity against Escherichia coli. By fluorescently labeling aptamer probes and applying FCS, we were able to study the diffusion dynamics of bound and unbound aptamers and compare them to determine the dissociation constants and receptor densities of the bacteria for each aptamer at single molecule sensitivity. The dissociation constants for these aptamer probes calculated from autocorrelation data were 0.1285 and 0.3772 nM and the respective receptor densities were 42.27 receptors per µm2 and 49.82 receptors per µm2. This study provides ample evidence that the number of surface receptors is sufficient for binding and that both aptamers have a high‐binding affinity and can therefore be used in detection processes. The methods developed here are unique and can be generalized to examine surface binding kinetics and receptor quantification in live bacteria at single molecule sensitivity levels. The impact of this study is broad because our approach can provide a methodology for biosensor construction and calculation of live single cell receptor‐ligand kinetics in a variety of environmental and biological applications. Bioeng. 2011; 108:1222–1227. © 2010 Wiley Periodicals, Inc.
Compatible Ionic liquid‐cellulases system for hydrolysis of lignocellulosic biomass
Authors: Wang Ying , Radosevich Mark , Hayes Douglas , Labbé Nicole
Published: December 2010

Ionic liquids (ILs) have been increasingly recognized as novel solvents for dissolution and pretreatment of cellulose. However, cellulases are inactivated in the presence of ILs, even when present at low concentrations. To more fully exploit the benefits of ILs it is critical to develop a compatible IL‐cellulases system in which the IL is able to effectively solubilize and activate the lignocellulosic biomass, and the cellulases possess high stability and activity. In this study, we investigated the stability and activity of a commercially available cellulases mixture in the presence of different concentrations of 1‐ethyl‐3‐methylimidazolium acetate ([Emim][OAc]). A mixture of cellulases and β‐glucosidase (Celluclast1.5L, from Trichoderma reesei, and Novozyme188, from Aspergillus niger, respectively) retained 77% and 65% of its original activity after being pre‐incubated in 15% and 20% (w/v) IL solutions, respectively, at 50°C for 3 h. The cellulases mixture also retained high activity in 15% [Emim][OAc] to hydrolyze Avicel, a model substrate for cellulose analysis, with conversion efficiency of approximately 91%. Notably, the presence of different amounts of yellow poplar lignin did not interfere significantly with the enzymatic hydrolysis of Avicel. Using this IL‐cellulase system (15% [Emim][OAc]), the saccharification of yellow poplar biomass was also significantly improved (33%) compared to the untreated control (3%) during the first hour of enzymatic hydrolysis. Together, these findings provide compelling evidence that [Emim][OAc] was compatible with the cellulase mixture, and this compatible IL‐cellulases system is promising for efficient activation and hydrolysis of native biomass to produce biofuels and co‐products from the individual biomass components. Bioeng. 2011; 108:1042–1048. © 2010 Wiley Periodicals, Inc.
Mannitol‐Guided delivery of ciprofloxacin in artificial cystic fibrosis mucus model
Authors: Yang Yan , Tsifansky Michael D. , Shin Sooyoung , Lin Qingnuo , Yeo Yoon
Published: December 2010

Abnormal airway mucus presents a significant challenge for inhalational drug delivery. Recognizing the thick and tenacious airway mucus seen in the cystic fibrosis (CF) patients as a critical barrier to effective drug delivery, both into the mucus layer itself as well as across that layer to the underlying airway epithelium, we hypothesize that mannitol or NaCl can form inhalable drug carriers, improve drug penetration into the mucus, and ultimately enhance the drug's therapeutic effect. The objective of this study is to test whether mannitol and NaCl particles, as inhalable drug carriers, improve drug delivery into and enhance a drug's activity within a mucus‐like material. Microparticles containing Ciprofloxacin (Cipro), an active ingredient, and either mannitol or NaCl were produced by spray‐drying. Cipro encapsulated in mannitol particles (Cipro–mannitol) was significantly more effective at killing Pseudomonas aeruginosa (P. aeruginosa) grown in artificial mucus (AM) than Cipro encapsulated in either NaCl particles (Cipro–NaCl) or in hydrophobic particles consisting of dipalmitoylphosphatidylcholine (DPPC), albumin, and lactose (Cipro–DAL). The relatively high antibacterial effectiveness of Cipro–mannitol was not due to the effect of mannitol on bacteria or on Cipro. Rather, the unique performance of the mannitol‐based particles in AM is attributable to its ability to increase local water content in the AM and enhance drug penetration into it. Mannitol is a promising excipient for inhalable microparticles that facilitate the drug delivery into the CF mucus. Biotechnol. Bioeng. 2011; 108:1441–1449. © 2010 Wiley Periodicals, Inc.
Biocatalytic process optimization based on mechanistic modeling of cholic acid oxidation with cofactor regeneration
Authors: Braun Michael , Link Hannes , Liu Luo , Schmid Rolf D. , Weuster‐Botz Dirk
Published: December 2010

Reduction and oxidation of steroids in the human gut are catalyzed by hydroxysteroid dehydrogenases of microorganisms. For the production of 12‐ketochenodeoxycholic acid (12‐Keto‐CDCA) from cholic acid the biocatalytic application of the 12α‐hydroxysteroid dehydrogenase of Clostridium group P, strain C 48–50 (HSDH) is an alternative to chemical synthesis. However, due to the intensive costs the necessary cofactor (NADP+) has to be regenerated. The alcohol dehydrogenase of Thermoanaerobacter ethanolicus (ADH‐TE) was applied to catalyze the reduction of acetone while regenerating NADP+. A mechanistic kinetic model was developed for the process development of cholic acid oxidation using HSDH and ADH‐TE. The process model was derived by identifying the parameters for both enzymatic models separately using progress curve measurements of batch processes over a broad range of concentrations and considering the underlying ordered bi–bi mechanism. Both independently derived kinetic models were coupled via mass balances to predict the production of 12‐Keto‐CDCA with HSDH and integrated cofactor regeneration with ADH‐TE and acetone as co‐substrate. The prediction of the derived model was suitable to describe the dynamics of the preparative 12‐Keto‐CDCA batch production with different initial reactant and enzyme concentrations. These datasets were used again for parameter identification. This led to a combined model which excellently described the reaction dynamics of biocatalytic batch processes over broad concentration ranges. Based on the identified process model batch process optimization was successfully performed in silico to minimize enzyme costs. By using 0.1 mM NADP+ the HSDH concentration can be reduced to 3–4 µM and the ADH concentration to 0.4–0.6 µM to reach the maximal possible conversion of 100 mM cholic acid within 48 h. In conclusion, the identified mechanistic model offers a powerful tool for a cost‐efficient process design. Biotechnol. Bioeng. 2011; 108:1307–1317. © 2010 Wiley Periodicals, Inc.
A unique and potent protein binding nature of liposome containing polyethylenimine and polyethylene Glycol: A nondisplaceable property
Authors: Liu Yen‐Ku , Lin Yu‐Ling , Chen Chia‐Hung , Lin Ching‐Min , Ma Kuan‐Lun , Chou Fu‐Hsuan , Tsai Jin‐Sheng , Lin Hsin‐Yu , Chen Fu‐Rong , Cheng Tian‐Lu , Chang Chia‐Ching , Liao Kuang‐Wen
Published: December 2010

Most of the currently available targeting vectors are produced via the linkage of targeting molecules. However, the coupling process is complicated, and the covalent linkage may attenuate the activity of certain targeting molecules. In this study, we have developed a cationic liposome complexed with polyethylenimine and polyethylene glycol polymers (LPPC) that can capture various proteins without covalent conjugation. Characterizations of prepared LPPC revealed that the maximal‐binding capacity was about 170 µg of bovine serum albumin to 40 µg of sphere‐shaped LPPC (180 nm). The proteins were essentially located at or near the surface when analyzed by atomic force or transmission electron microscopy. We demonstrate that polyethylenimine was an essential component to bind the proteins. Upon the saturation of captured proteins, a given protein could not be displaced by other additional proteins and still retained its biological activity. Using a variety of functional proteins, we show some typical examples of the utility of incorporated beta‐glucuronidase and antibodies onto the LPPC. The beta‐glucuronidase can be used for the study of antigen–antibody interactions, whereas in studies with the antibody complex, we used anti‐CD3 as an agonist to stimulate the proliferation of peripheral blood mononuclear cells via a receptor‐mediated mechanism and anti‐VEGFR for cell staining. In conclusion, the prepared LPPC can provide a platform to capture biologically and biochemically functional proteins on its surface for various applications, such as cell signaling, cell profiling, noncovalent enzyme‐linked immunoassays, and others not mentioned. Biotechnol. Bioeng. 2011; 108:1318–1327. © 2010 Wiley Periodicals, Inc.
Preliminary approach of real‐time monitoring in vitro matrix mineralization based on surface plasmon resonance detection
Authors: Kim Shin Ae , Das Sumit , Lee Howon , Kim Junghoon , Song Yun Mi , Kim In Sook , Byun Kyung Min , Hwang Soon Jung , Kim Sung June
Published: December 2010

Matrix mineralization is a terminal process in osteoblast differentiation, and several approaches have been introduced to characterize the process in tissues or cultured cells. However, an analytical technique that quantitates in vitro matrix mineralization of live cells without any labeling or complex treatments is still lacking. In this study, we investigate a simple and enhanced optical method based on surface plasmon resonance (SPR) detection that can monitor the surface‐limited refractive index change in real‐time. During monitoring MC3T3‐E1 cells in vitro culture every 2 days for over 4 weeks, the SPR angle is shifted with a greater resonance change in cells cultured with osteogenic reagents than those without the reagents. In addition, the SPR results obtained have a close relevance with the tendency of conventional mineralization staining and an inductively coupled plasma‐based calcium content measure. These results suggest a new approach of a real‐time SPR monitoring in vitro matrix mineralization of cultured cells. Biotechnol. Bioeng. 2011; 108:1473–1478. © 2010 Wiley Periodicals, Inc.
Comparative study of CAD–CAE programs taking account of the opinions of students and teachers
Authors: Díaz Lantada Andrés , Lafont Morgado Pilar , Munoz‐Guijosa Juan Manuel , Echávarri Otero Javier , Muñoz Sanz José Luis
Published: December 2010

Computer‐aided design or simulation courses are usually focused on the use of a single CAD–CAE package, chosen according to specific criteria or final application. However, on the “Expert in CAD–CAE Technologies” course, taught annually at the Machine Engineering Division of the Universidad Politécnica de Madrid, we have chosen a multidisciplinary approach based on the use of three different CAD–CAE software packages, as the following paragraph will describe. This work details the results of a comparison between the CAD–CAE programs taught on that course (NX‐6, Catia v.5 r.17 and Solid Edge v.20). The work has been conducted taking into account the opinions of students and teachers on important technical and practical aspects concerning the different design, simulation and calculation modules. With this comparison, it is hoped to attain a progressive increase in teaching quality by bearing in mind students' satisfaction with their own learning as a relevant factor, in accordance with the guidelines set by the Bologna Declaration regarding the implementation of the European Higher Education Area and the new quality assessment trends in teaching. Studies similar to this one may be highly useful when assessing whether the use of different software will be sufficient, as well as in situations where a choice needs to be made from among several programs in order to promote some particularly important aspect or activity. The opinions of teachers as well as students are important, particularly when students are seeking a job in Industry, as it is possible to take some urgent and very necessary steps that will meet the requirements demanded in job interviews. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 641–656, 2013
Learning hydraulic turbomachinery with computational fluid dynamics (CFD) codes
Authors: Pujol T. , Montoro L. , Pelegrí M. , González J. R.
Published: December 2010

In fluid mechanics courses of engineering curricula, theoretical performance curves of hydraulic turbines are obtained by means of simple analytical expressions that tend to overestimate experimental data. As we show here in the analysis of a laboratory‐scale Pelton wheel, a much deeper physical insight can be achieved by means of general‐purpose commercial computational fluid dynamics (CFD) software programs, becoming a suitable tool for academic activities. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 684–690, 2013
An educational laboratory virtual EES for encouraging the use of computer programming in thermal engineering problems
Authors: Zueco Joaquín
Published: December 2010

General computational software systems (such as Mathcad, Matlab, Techplot, LabView, Fluent, EES (Engineering Equation Solver), and Mathematica) with great flexibility are available for use on personal computers. This paper examines the application of one of these systems, EES, to a number of preliminary thermal sciences calculations, being a generalized EES. This software is a powerful equation solver with built‐in functions and property tables for thermodynamics and transport properties as well as automatic unit checking capability. Application examples include close system of mix adiabatic of ideals gases and simple and generalized counter‐flow cooling tower system. This program has demonstrated to be a useful tool that offers great flexibility and generality as well as congruence with problem formulation. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 691–697, 2013
A Modified Epigenetics Toolbox to Study Histone Modifications on the Nucleosome Core
Authors: Frederiks Floor , Stulemeijer Iris J. E. , Ovaa Huib , van Leeuwen Fred
Published: December 2010

In the eukaryotic cell nucleus, the DNA is packaged in a structure called chromatin. The fundamental building block of chromatin is the nucleosome, which is composed of DNA wrapped around an octamer of four distinct histone proteins. Post‐translational modifications (PTMs) of histone proteins can affect chromatin structure and function and thereby play critical roles in regulating gene expression. Most histone PTMs are found in unstructured histone tails that protrude from the nucleosome core. As a consequence, (synthetic) peptide truncations of these tails provide convenient substrates for the analysis of histone binding proteins and modifying enzymes. Modifications located on residues that reside in the nucleosome core are more difficult to study because short peptides do not recapitulate this defined structured state well. Methylation of histone H3 on Lys79 (H3K79), mediated by the Dot1 enzyme, is an example of such a core PTM. This modification, which is highly conserved, is linked to human leukemia, and pharmacological modulation of Dot1 activity could be a strategy to treat leukemia. Here we review the available and emerging genetic, biochemical, and chemical methods that together are starting to reveal the function and regulation of this and other histone modifications on the nucleosome core.
Experimental Results and Model for N‐Gas Compound Production in Pure Steam Gasification for Wastewater Sewage Sludge
Authors: Ferrasse J.‐H. , Dumas C. , Roche N.
Published: December 2010

Sewage sludge produced in wastewater treatment plants represent a significant portion of waste resulting from human activity and it is important to offer new ways of treatment. Thermal gasification of sludge is a promising thermal treatment, particularly because it can lead to a recovery of energy and a drastic reduction in the initial waste volume. However, it is a subject that has rarely been treated in the literature for sewage sludge. In particular, the nitrogen compounds present in significant quantities in the sewage sludge and their reactions during a thermal gasification step, must necessarily be taken into account. In order to study nitrogen behavior, this paper presents experimental results that are included in a model to predict NH3 emission.
Adaptive Robust Generic Model Control of High‐Purity Internal Thermally Coupled Distillation Column
Authors: Liu X. , Wang C. , Cong L.
Published: December 2010

The internal thermally coupled distillation column (ITCDIC) is a frontier in energy‐saving distillation research. The process inside a high‐purity ITCDIC is of great nonlinear dynamics, which trouble the conventional control schemes. A multivariable adaptive robust generic model control (ARGMC) is presented to solve the difficulties, where an ARX model is derived and a recursive least squares estimation (RLSE) method is introduced. The benzene/toluene system is studied as an illustrative example. The results of ARGMC are compared with the robust generic model control (RGMC) and traditional PID control in detail. The performances in both servo control and regulatory control confirm the accuracy and validity of ARGMC for the high‐purity ITCDIC process.
Transmission of Alkali Aerosols through Sampling Systems
Authors: Kowalski T. , Judex J. , Schildhauer T. J. , Ludwig C.
Published: December 2010

In biomass gasification, particles such as condensed alkali salts pose a threat on equipment. Due to high loads of condensable tars in the gases, sampling of these particles to liquids and subsequent analysis of the liquid is frequently the method of choice for measuring the alkali concentration in the gas. However, little is known about the collection efficiency of liquid sampling devices. By measuring the aerosol transmission using a surface ionization detector, two continuous sampling systems are compared with conventional impinger bottles. A low collection efficiency for the latter was found, but down to nearly zero transmission for the continuous sampling systems. The main mechanisms for mass transfer from gas to liquid are discussed with emphasis on particle removal in gas slugs in two‐phase flow inside tubes of the sampling system.
Variation in likelihood ratios for forensic evidence evaluation of XTC tablets comparison
Authors: Bolck Annabel , Alberink Ivo
Published: December 2010

In forensic comparison casework, where it is investigated whether items are from the same source, the likelihood ratio (LR) is a measure for evaluating the strength of evidence of the observed (dis)similarity between these items. The paper concentrates on evaluation of various LR models for comparison of XTC tablets from different production batches. Starting from a two‐level random effect model, where means are considered random, the distribution of these means may be assumed normal or approximated by kernel density estimations (KDEs), and variation in the data may or may not be allowed to differ per batch. It is investigated what effect the corresponding model and estimation choices have on the distribution of LRs for same‐ and different‐batch comparisons. Copyright © 2010 John Wiley & Sons, Ltd.
Screening design for computer experiments: metamodelling of a deterministic mathematical model of the mammalian circadian clock
Authors: Tøndel Kristin , Gjuvsland Arne B. , Måge Ingrid , Martens Harald
Published: December 2010

Computer simulations are faster and cheaper than physical experiments. Still, if the system has many factors to be manipulated, experimental designs may be needed in order to make computer experiments more cost‐effective. Determining the relevant parameter ranges within which to set up a factorial experimental design is a critical and difficult step in the practical use of any formal statistical experimental planning, be it for screening or optimisation purposes. Here we show how a sparse initial range finding design based on a reduced multi‐factor multi‐level design method—the multi‐level binary replacement (MBR) design—can reveal the region of relevant system behaviour. The MBR design is presently optimised by generating a number of different confounding patterns and choosing the one giving the highest score with respect to a space‐spanning criterion. The usefulness of this optimised MBR (OMBR) design is demonstrated in an example from systems biology: A multivariate metamodel, emulating a deterministic, nonlinear dynamic model of the mammalian circadian clock, is developed based on data from a designed computer experiment. In order to allow the statistical metamodel to represent all aspects of the biologically relevant model behaviour, the relevant parameter ranges have to be spanned. The use of an initial OMBR design for finding the widest possible parameter ranges resulting in a stable limit cycle for the mammalian circadian clock model is demonstrated. The same OMBR design is subsequently applied within the selected, relevant sub‐region of the parameter space to develop a functional metamodel based on PLS regression. Copyright © 2010 John Wiley & Sons, Ltd.
Multi‐level binary replacement (MBR) design for computer experiments in high‐dimensional nonlinear systems
Authors: Martens Harald , Måge Ingrid , Tøndel Kristin , Isaeva Julia , Høy Martin , Sæbø Solve
Published: December 2010

Computer experiments are useful for studying a complex system, e.g. a high‐dimensional nonlinear mathematical model of a biological or physical system. Based on the simulation results, an empirical “metamodel” may then be developed, emulating the behavior of the model in a way that is faster to compute and easier to understand. In modelometrics, the model phenome of a computer model is recorded, once and for all, by structured simulations according to a factorial design in the model inputs, and with high‐dimensional profiling of its simulation outputs. A multivariate metamodel is then developed, by multivariate analysis of the input–output data, akin to how high‐dimensional data are analyzed in chemometrics. To reveal strongly nonlinear input–output relationships, the factorial design must probe the design space at many different levels for each of the many input factors. A reduced factorial design method may be required if combinatorial explosion is to be avoided. In the multi‐level binary replacement (MBR) design the levels of each input factor are represented as binary numbers, and all the individual binary factor bits are then combined in a fractional factorial (FF) design. The experiment size can thereby be greatly reduced at the price of some binary confounding. The MBR method is here described and then illustrated for the optimization of a nonlinear model of a microbiological growth curve with five design factors, for finding the relevant region in the design space, and subsequently for estimating the optimal design points in that space. Copyright © 2010 John Wiley & Sons, Ltd.
Remodelling and pathology development associated with aneurysmal ascending aortic tissues
Authors: Tremblay Dominique , Leask Richard L.
Published: December 2010

The human ascending aorta (AA) is exposed to very high shear and pressure stresses exerted by the blood flow ejected from the left ventricle outflow tract. This vessel has a unique structural behaviour which adequately redistributes the energy captured from the blood flow ejection to sustain a more continuous blood flow through the entire vascular system. Unfortunately, this vessel is prone to a pathological dilation process involving significant structural changes that can lead to fundamental modification of its mechanical behaviour and functions. Genetic and/or environmental factors have been implicated in the disease process. It is believed that in particular the forces created by blood flow (hemodynamics) can be a stimulus for vessel remodelling. For patients suffering from this deadly condition, surgical replacement or repair is the best solution to increase life expectancy. However, the replacement materials available as a treatment have a significant impact on the blood flow, the biomechanics of the aortic arch, and the entire vascular system. In this review we summarise the current understanding of the pathogenesis mechanisms involved in the dilation of the AA from a mechanical and biochemical point of view. We will also underline the needs for better replacement materials in surgical repair to improve graft patency.
Density functional modelling in multiphase compositional hydrodynamics
Authors: Demianov Alexander , Dinariev Oleg , Evseev Nikolay
Published: December 2010

This work is essentially a review of a density functional approach in multiphase hydrodynamics developed by the authors during the last 15 years [Dinariev, J Appl Math Mech 1995;59(5):745–752; Dinariev, J Appl Math Mech 1998;62(3):397–405; Demyanov and Dinariev, Fluid Dynam 2004;39(6):933–944; Demianov et al., “Basics of the Density Functional Theory in Hydrodynamics,” Fizmatlit, Moscow; 2009 (in Russian); Dinariev and Evseev, Fluid Dynam 2010;45(1):85–95]. The basic assumption is a representation of the entropy or the Helmholtz energy of the mixture as a functional that is dependent upon chemical component densities. The hydrodynamic system of equations (local conservation laws for chemical components, momentum, and energy) is used to describe multiphase processes, and the constitutive relations (expressions for stresses, diffusion, and heat fluxes) are derived from entropy growth requirement. The authors present the results of numerical simulations describing static and dynamic multiphase systems.
In vitro biomedical applications of functionalized iron oxide nanoparticles, including those not related to magnetic properties
Authors: Burtea Carmen , Laurent Sophie , Mahieu Isabelle , Larbanoix Lionel , Roch Alain , Port Marc , Rousseaux Olivier , Ballet Sébastien , Murariu Oltea , Toubeau Gérard , Corot Claire , Vander Elst Luce , Muller Robert N.
Published: December 2010

Superparamagnetic iron oxide nanoparticles (SPION) are very promising contrast media, especially for molecular imaging, due to their superior NMR efficacy. They even have wider biomedical applications such as in drug and gene delivery, tissue engineering and bioseparation, or as sensitive biological nanosensors. By coupling them to affinity ligands, SPION can bind to drugs, proteins, enzymes, antibodies or nucleotides. For in vitro biomedical applications, the detection of molecular interaction is possible by using a diversity of systems capable of sensing the magnetic properties of these materials. The goal of the present work was to develop and validate various in vitro biomedical applications of ultrasmall superparamagnetic particles of iron oxide (USPIO), including some that are not related to their magnetic properties. USPIO coated with dextran, starch or bisphosphonate exposing carboxylate groups were synthesized and some of them were functionalized by conjugating various biomolecules, such as biotin, streptavidin and apoptosis, or VCAM‐1 specific peptides. The in vitro biomedical applications assessed in the present work included: (1) the relaxometric measurement of antibody concentration, cell receptor expression, molecular interaction, and enzymatic activity in aqueous suspensions; (2) MRI visualization of cells and detection of molecular interaction in an ELISA system; (3) ELISA applications of USPIO derivatives; and (4) detection of specific biomolecules by histochemistry. Our results confirm that rapid and simple in vitro detection of a diversity of functionalized SPION with relevance in medicine is possible by the existing NMR techniques and by chemical staining reactions. The protocols can be applied to minimally prepared biological samples (e.g. whole blood, blood plasma or serum, cell suspensions, biopsies, histological preparations, etc.), and often do not need complicated systems of signal amplification. The use of SPION labeled compounds could furthermore contribute to cost reductions in the diagnosis and in patient care. Copyright © 2010 John Wiley & Sons, Ltd.
Ixabepilone, mitoxantrone, and prednisone for metastatic castration‐resistant prostate cancer after docetaxel‐based therapy
Authors: Harzstark Andrea L. , Rosenberg Jonathan E. , Weinberg Vivian K. , Sharib Jeremy , Ryan Charles J. , Smith David C. , Pagliaro Lance C. , Beer Tomasz M. , Liu Glenn , Small Eric J.
Published: December 2010

BACKGROUND:

Mitoxantrone plus prednisone and ixabepilone each have modest activity as monotherapy for second‐line chemotherapy in patients with docetaxel‐refractory castration‐resistant prostate cancer. Clinical noncross‐ resistance was previously observed. Phase 1 testing determined the maximum tolerated dose and dose‐limiting toxicities with the combination regimen; a phase 2 study was conducted to evaluate the activity of the combination.

METHODS:

Patients with metastatic progressive castration‐resistant prostate cancer during or after 3 or more cycles of taxane‐based chemotherapy enrolled in a phase 2 multicenter study of ixabepilone 35 mg/m2 and mitoxantrone 12 mg/m2 administered on Day 1 every 21 days with pegfilgrastim support, along with prednisone 5 mg twice daily. Patients were evaluated for disease response and toxicity.

RESULTS:

Results are reported for the 56 evaluable patients. Twenty‐five (45%; 95% confidence interval [CI], 31%‐59%) experienced confirmed ≥50% prostate‐specific antigen (PSA) declines, 33 (59%; 95% CI, 45%‐72%) experienced confirmed ≥30% PSA declines, and 8 of 36 patients (22%; 95% CI, 10%‐39%) with measurable disease experienced objective responses. Median time to PSA or objective progression was 4.4 months (95% CI, 3.5‐5.6), and median progression‐free survival was also 4.4 months (95% CI, 3.0‐6.0). Median overall survival was 12.5 months (95% CI, 10.2‐15.9). Thirty‐two percent of patients experienced grade 3 of 4 neutropenia, and 11% experienced grade 3 or higher neutropenic infections, including 1 treatment‐related death. Grade 2 and 3 neuropathy occurred in 11% and 12.5% of patients, respectively.

CONCLUSIONS:

These results suggest that the combination of ixabepilone and mitoxantrone is both feasible and active in castration‐resistant prostate cancer and requires dosing with pegfilgrastim. Cancer 2011;. © 2010 American Cancer Society.
Satisfaction with ovarian carcinoma risk‐reduction strategies among women at high risk for breast and ovarian carcinoma
Authors: Westin Shannon N. , Sun Charlotte C. , Lu Karen H. , Schmeler Kathleen M. , Soliman Pamela T. , Lacour Robin A. , Johnson Kristin G. , Daniels Molly S. , Arun Banu K. , Peterson Susan K. , Bodurka Diane C.
Published: December 2010

BACKGROUND:

Women who are at high risk for breast and ovarian cancer have 2 major management options to reduce their risk of ovarian cancer: periodic screening (PS) or risk‐reducing salpingo‐oophorectomy (RRSO). Little is known regarding patient satisfaction levels with risk‐reduction strategies. Thus, the authors sought to determine levels of patient satisfaction with PS versus RRSO and to identify factors that may influence satisfaction.

METHODS:

As part of a larger study, women who received testing for the breast cancer genes BRCA1 and BRCA2 were sent a follow‐up questionnaire packet to explore issues related to cancer risk reduction. The authors report on the results from a variety of validated instruments, including the Satisfaction With Decision (SWD) scale, focused on the choice between PS and RRSO.

RESULTS:

In total, 544 surveys were mailed, and 313 responses were received (58%). The overall satisfaction rate among respondents was high. The median SWD score was significantly higher in the RRSO group compared with the PS group (P < .001). BRCA mutation carriers had higher median SWD scores regardless of management type (P = .01). Low satisfaction scores were associated with high levels of uncertainty and the perception that the decision between PS and RRSO was difficult to make (P = .001). Satisfaction was unrelated to demographics, clinical factors, or concerns of cancer risk.

CONCLUSIONS:

In the current study, the majority of women who were at high risk for breast and ovarian cancer were satisfied with their choice of risk‐reduction strategy. Difficulty with decision making was associated with lower satisfaction levels. Improved education and support through the decision‐making process may enhance overall levels of satisfaction. Cancer 2011. © 2010 American Cancer Society.
A note from history: Landmarks in history of cancer, part 2
Authors: Hajdu Steven I.
Published: December 2010

Events that took place in medicine during the 15th, 16th, and 17th centuries signaled the end of the Dark Ages. The Renaissance movement, spreading from Italy across Europe, ended the religious and public prohibitions that had prevented progress in medicine. Pioneer physicians and surgeons who gave their attention to discoveries in anatomy, physiology, and chemistry established the foundations for tumor pathology, surgical oncology, and medical oncology. This review is a summary of their accomplishments. Cancer 2011. © 2010 American Cancer Society.
FRET in Cell Biology: Still Shining in the Age of Super‐Resolution?
Authors: Grecco Hernán E. , Verveer Peter J.
Published: December 2010

Interest in imaging of Förster resonance energy transfer (FRET) in biological systems has been steadily increasing in the last 30 years. The ability to transduce a near‐field interaction into a far‐field signal has provided a unique optical tool to assess biological phenomena well below the resolution of standard optical microscopy. In recent years, sub‐diffraction microscopy techniques have achieved maturation and are increasingly used in biological applications. As the resolution of these methods increases they will slowly encroach on the domains where FRET is now dominant. Herein we review the major applications in biological FRET imaging and we discuss the possibilities and challenges in the super‐resolution era.
Surface‐Directed Spinodal Decomposition of Solvent‐Quenched Organic Transistor Blends
Authors: Michels Jasper J.
Published: December 2010

This paper describes the first example of the application of a combination of the Flory–Huggins and Cahn–Hilliard theories to model and simulate microstructure evolution in solution‐processed functional blend layers of organic semiconductors, as used in organic electronics devices. Specifically, the work considers phase separation of the active blend components of organic transistors based on triisopropylsilylpentacene (TIPS‐pentacene) and poly(α‐methylstyrene) (PαMS). By calculation and estimation of relevant physical parameters, it is shown that the vertically phase‐separated structure observed in as‐cast blend layers containing PαMS of a sufficiently high molecular weight (of the order of 102 kDa) evolves via surface‐directed spinodal decomposition. The surface‐directed effect can already be triggered by small differences in substrate– and/or air–interface interaction energies of the separating phases. During phase separation, which commences at the interfaces, bulk features of the TIPS‐enriched phase formed by thermal noise collapse to give the experimentally observed trilayer structure of TIPS–PαMS–TIPS. The reported near absence of solution‐state phase separation of as‐cast blend layers containing a low molecular weight PαMS (of the order of 1 kDa) is also reproduced.
The Visible Intensified Cameras for Plasma Imaging in the TJ‐II Stellarator
Authors: de la Cal E. , Carralero D. , de Pablos J. L. , Alonso A. , Rios L. , García Sánchez P. , Hidalgo C.
Published: December 2010

Visible cameras are widely used in fusion experiments for diagnosis and for machine safety issues. They are generally used to monitor the plasma emission, but are also sensible to surface Blackbody radiation and Bremsstrahlung. Fast or high speed cameras capable of operating in the 105frames per second speed range are today commercially available and offer the opportunity to plasma fusion researchers of two‐dimensional (2D) imaging of fast phenomena such as turbulence, ELMs, disruptions, dust, etc. The tracking of these fast phenomena requires short exposure times down to theμs range and the light intensity can be often near the signal to noise ratio limit especially in low plasma emission regions such as the far SOL Additionally, when using interference filters to monitor, e.g. impurity line emission, the photon flux is strongly reduced and the emission cannot be imaged at high speed. Therefore, the use of image intensifiers that amplify the light intensity onto the camera sensor can be of great help. The present work describes the use of intensifiers in the visible fast cameras of TJ‐II stellarator. We have achieved spectroscopic plasma imaging of filtered impurity atomic line emission at short exposure times down to the 10μs range depending on atomic line and concentration. Additionally, plasma movies at velocities of 2x105frames per second near the camera operation limit can be recorded with exposure times well below 1μs with sufficient signal to noise ratio. Although an increasing degradation of the image quality appears when raising the light amplification, an effective gain of up to two orders of magnitude of the light intensity is feasible for many applications (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wave Instabilities of a Collisionless Plasma in Fluid Approximation
Authors: Dzhalilov N. S. , Kuznetsov V. D. , Staude Jürgen
Published: December 2010

Wave properties and instabilities in a magnetized, anisotropic, collisionless, rarefied hot plasma in fluid approx‐imation are studied, using the 16‐moments set of the transport equations obtained from the Vlasov equations. These equations differ from the CGL‐MHD fluid model (single fluid equations by Chew, Goldberger, and Low [5,9]) by including two anisotropic heat flux evolution equations, where the fluxes invalidate the double polytropic CGL laws. We derived the general dispersion relation for linear compressible wave modes. Besides the classic incompressible fire hose modes there appear four types of compressible wave modes: two fast and slow mirror modes – strongly modified compared to the CGL model – and two thermal modes. In the presence of initial heat fluxes along the magnetic field the wave properties become different for the waves running forward and backward with respect to the magnetic field. The well known discrepancies between the results of the CGL‐MHD fluid model and the kinetic theory are now removed: i) The mirror slow mode instability criterion is now the same as that in the kinetic theory. ii) Similarly, in kinetic studies there appear two kinds of fire hose instabilities ‐ incompressible and compressible ones. These two instabilities can arise for the same plasma parameters, and the instability of the new compressible oblique fire hose modes can become dominant. The compressible fire hose instability is the result of the resonance coupling of three retrograde modes ‐ two thermal modes and a fast mirror mode. The results can be applied to the theory of solar and stellar coronal and wind models (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum Theory of Solid State Plasma Dielectric Response
Authors: Morgenstern Horing N. J.
Published: December 2010

We review the quantum mechanical derivation of the random phase approximation (RPA) for solid state plasmas, starting from the Hamilton equations for canonically paired “second quantized” creation and annhilation field operators of interacting quantum many‐body systems. Discussing variational differentiation, the coupled equations of motion for the quantum field operators are derived. The concept of Green's functions is reviewed and interpreted, first for retarded Green's functions, and their equations of motion are developed from the equations of motion for the field operators. Thermodynamic Green's functions are discussed, and their periodicity/antiperiodicity properties in imaginary time are carefully examined with discussion of Matsubara Fourier series and representation in terms of a spectral weight function. The analytic continuation from imaginary time to real time is treated. Finally, we define nonequilibrium Green's functions and discuss the linearized timedependent Hartree approximation leading to the random phase approximation. An interesting application to the case of Graphene in a perpendicular magnetic field is discussed in detail, along with applications to normal systems, in terms of attendant phenomenology involving electron‐hole pair excitations and plasmons (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Appropriate Bmp7 levels are required for the differentiation of midline guidepost cells involved in corpus callosum formation
Authors: Sánchez‐Camacho Cristina , Ortega Juan Alberto , Ocaña Inmaculada , Alcántara Soledad , Bovolenta Paola
Published: December 2010

Guidepost cells are essential structures for the establishment of major axonal tracts. How these structures are specified and acquire their axon guidance properties is still poorly understood. Here, we show that in mouse embryos appropriate levels of Bone Morphogenetic Protein 7 (Bmp7), a member of the TGF‐β superfamily of secreted proteins, are required for the correct development of the glial wedge, the indusium griseum, and the subcallosal sling, three groups of cells that act as guidepost cells for growing callosal axons. Bmp7 is expressed in the region occupied by these structures and its genetic inactivation in mouse embryos caused a marked reduction and disorganization of these cell populations. On the contrary, infusion of recombinant Bmp7 in the developing forebrain induced their premature differentiation. In both cases, changes were associated with the disruption of callosal axon growth and, in most animals fibers did not cross the midline forming typical Probst bundles. Addition of Bmp7 to cortical explants did not modify the extent of their outgrowth nor their directionality, when explants were exposed to a focalized source of the protein. Together, these results indicate that Bmp7 is indirectly required for corpus callosum formation by controlling the timely differentiation of its guidepost cells. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 337–350, 2011
Stability‐indicating spectrophotometric and spectrodensitometric methods for the determination of diacerein in the presence of its degradation product
Authors: Nebsen Marianne , Abd El‐Rahman Mohamed K. , Salem Maissa Y. , El‐Kosasy Amira M. , El‐Bardicy Mohamed G.
Published: December 2010

Three sensitive, selective, and precise stability‐indicating methods for the determination of the novel osteoarthritis drug, diacerein (DIA) in the presence of its alkaline degradation product (active metabolite, rhein) and in pharmaceutical formulation were developed and validated. The first method is a first derivative (D1) spectrophotometric one, which allows the determination of DIA in the presence of its degradate at 322 nm (corresponding to zero crossing of the degradate) over a concentration range of 4–40 µg/mL with mean percentage recovery 100.21 ± 0.833. The second method is the first derivative of the ratio spectra (DD1) by measuring the peak amplitude at 352 nm over the same concentration range as (D1) spectrophotometric method, with mean percentage recovery 100.09 ± 0.912. The third method is a TLC‐densitometric one, where DIA was separated from its degradate on silica gel plates using ethyl acetate:methanol:chloroform (8:1.5:0.5 v:v:v) as a developing system. This method depends on quantitative densitometric evaluation of thin layer chromatogram of DIA at 340 nm over a concentration range of 1–10 µg/spot, with mean percentage recovery 100.24 ± 1.412. The selectivity of the proposed methods was tested using laboratory‐prepared mixtures. The proposed methods have been successfully applied to the analysis of DIA in pharmaceutical dosage forms without interference from other dosage form additives and the results were statistically compared with reference method. Copyright © 2010 John Wiley & Sons, Ltd.