bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors influencing alginate gel biocompatibility
Authors: Tam Susan K. , Dusseault Julie , Bilodeau Stéphanie , Langlois Geneviève , Hallé Jean‐Pierre , Yahia L'Hocine
Published: April 2011

Alginate remains the most popular polymer used for cell encapsulation, yet its biocompatibility is inconsistent. Two commercially available alginates were compared, one with 71% guluronate (HiG), and the other with 44% (IntG). Both alginates were purified, and their purities were verified. After 2 days in the peritoneal cavity of C57BL/6J mice, barium (Ba)‐gel and calcium (Ca)‐gel beads of IntG alginate were clean, while host cells were adhered to beads of HiG alginate. IntG gel beads, however, showed fragmentation in vivo while HiG gel beads stayed firm. The physicochemical properties of the sodium alginates and their gels were thoroughly characterized. The intrinsic viscosity of IntG alginate was 2.5‐fold higher than that of HiG alginate, suggesting a greater molecular mass. X‐ray photoelectron spectroscopy indicated that both alginates were similar in elemental composition, including low levels of counterions in all gels. The wettabilities of the alginates and gels were also identical, as measured by contact angles of water on dry films. Ba‐gel beads of HiG alginate resisted swelling and degradation when immersed in water, much more than the other gel beads. These results suggest that the main factors contributing to the biocompatibility of gels of purified alginate are the mannuronate/guluronate content and/or intrinsic viscosity. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Cathepsin K‐sensitive poly(ethylene glycol) hydrogels for degradation in response to bone resorption
Authors: Hsu Chih‐Wei , Olabisi Ronke M. , Olmsted‐Davis Elizabeth A. , Davis Alan R. , West Jennifer L.
Published: April 2011

We propose a new strategy of biomaterial design to achieve selective cellular degradation by the incorporation of cathepsin K‐degradable peptide sequences into a scaffold structure so that scaffold biodegradation can be induced at the end of the bone formation process. Poly(ethylene glycol) diacrylate (PEGDA) hydrogels were used as a model biomaterial system in this study. A cathepsin K‐sensitive peptide, GGGMGPSGPWGGK (GPSG), was synthesized and modified with acryloyl‐PEG‐succinimidyl carbonate to produce a cross‐linkable cathepsin K‐sensitive polymer that can be used to form a hydrogel. Specificity of degradation of the GPSG hydrogels was tested with cathepsin K and proteinase K as a positive control, with both resulting in significant degradation compared to incubation with nonspecific collagenases over a 24‐h time period. No degradation was observed when the hydrogels were incubated with plasmin or control buffers. Cell‐induced degradation was evaluated by seeding differentiated MC3T3‐E1 osteoblasts and RAW264.7 osteoclasts on GPSG hydrogels that were also modified with the cell adhesion peptide RGDS. Resulting surface features and resorption pits were analyzed by differential interference contrast (DIC) and fluorescent images obtained with confocal microscopy. Results from both analyses demonstrated that GPSG hydrogels can be degraded specifically in response to osteoclast attachment but not in response to osteoblasts. In summary, we have demonstrated that by incorporating a cathepsin K‐sensitive peptide into a synthetic polymer structure, we can generate biomaterials that specifically respond to cues from the natural process of bone remodeling. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Exclusion of the GNAS locus in PHP-Ib patients with broad GNAS methylation changes: Evidence for an autosomal recessive form of PHP-Ib?
Authors: Fernández-Rebollo Eduardo , Pérez de Nanclares Guiomar , Lecumberri Beatriz , Turan Serap , Anda Emma , Pérez-Nanclares Gustavo , Feig Denice , Nik-Zainal Serena , Bastepe Murat , Jüppner Harald
Published: April 2011

Most patients with autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib) carry maternally inherited microdeletions upstream of GNAS that are associated with loss of methylation restricted to GNAS exon A/B. Only few AD-PHP-Ib patients carry microdeletions within GNAS that are associated with loss of all maternal methylation imprints. These epigenetic changes are often indistinguishable from those observed in patients affected by an apparently sporadic PHP-Ib form that has not yet been defined genetically. We have now investigated six female patients affected by PHP-Ib (four unrelated and two sisters) with complete or almost complete loss of GNAS methylation, whose healthy children (11 in total) showed no epigenetic changes at this locus. Analysis of several microsatellite markers throughout the 20q13 region made it unlikely that PHP-Ib is caused in these patients by large deletions involving GNAS or by paternal uniparental isodisomy or heterodisomy of chromosome 20 (patUPD20). Microsatellite and single-nucleotide variation (SNV) data revealed that the two affected sisters share their maternally inherited GNAS alleles with unaffected relatives that lack evidence for abnormal GNAS methylation, thus excluding linkage to this locus. Consistent with these findings, healthy children of two unrelated sporadic PHP-Ib patients had inherited different maternal GNAS alleles, also arguing against linkage to this locus. Based on our data, it appears plausible that some forms of PHP-Ib are caused by homozygous or compound heterozygous mutation(s) in an unknown gene involved in establishing or maintaining GNAS methylation. © 2011 American Society for Bone and Mineral Research
Influence of fetal bovine serum on cytotoxic and genotoxic effects of lectins in MCF‐7 cells
Authors: Faheina‐Martins Glaucia Veríssimo , da Silveira Alethéia Lacerda , Ramos Márcio Viana , Marques‐Santos Luís Fernando , Araujo Demetrius Antonio Machado
Published: April 2011

Canavalia ensiformis (ConA), Canavalia brasiliensis (Conbr), and Cratylia floribunda (CFL) lectins have exhibited glucose‐mannose binding specificity. We investigated the effect of fetal bovine serum (FBS) concentrations (1, 5, 10, and 20%) on the cytotoxic effect of these lectins against breast tumor cell line MCF‐7. Cell viability was examined using the MTT reduction assay. When cells were grown in a medium supplemented with a higher serum concentration (10 or 20%), all lectins were much less toxic. When we used 1% FBS, it was possible to achieve a concentration‐dependent activity by all examined lectins, with an IC50 of 3.5, 25, and 60 µg/mL for ConA, Conbr, and CFL, respectively. All lectins incubated with 1% FBS induced apoptosis and DNA damage in MCF‐7 cells. We conclude that ConA, Conbr, and CFL lectins' cytotoxic and genotoxic effects were observed only at low concentrations of serum. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:290–296, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20388
Neither nitrite nor nitric oxide mediate toxic effects of nitroglycerin on mitochondria
Authors: Dungel Peter , Haindl Susanne , Behling Tricia , Mayer Bernd , Redl Heinz , Kozlov Andrey V.
Published: April 2011

It is commonly accepted that the major effect of nitroglycerin (NG) is realized through the release of nitric oxide (NO) catalyzed by aldehyde dehydrogenase‐2 (ALDH2). In addition, it has been shown that NG inhibits mitochondrial respiration. The aim of this study was to clarify whether NG‐mediated inhibition of mitochondrial respiration is mediated by NO. In rat liver mitochondria, NG inhibited complex‐I‐dependent respiration and induced reactive oxygen species (ROS) production, preferentially at complex I. Both effects were insensitive to chloral hydrate, an ALDH2 inhibitor. Nitrite, an NG intermediate, had no influence on either mitochondrial respiration or the production of ROS. NO inhibited preferentially complex I but did not elevate ROS production. Hemoglobin, an NO scavenger, and blue light had contrary effects on mitochondria inhibited by NO or NG. In summary, our data suggest that although NG induces vasodilatation via NO release, it causes mitochondrial dysfunction via an NO‐independent pathway. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:297–302, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20389
Gene expression profiling to examine the thyroid hormone‐disrupting activity of hydroxylated polychlorinated biphenyls in metamorphosing amphibian tadpole
Authors: Ishihara Akinori , Makita Yu , Yamauchi Kiyoshi
Published: April 2011

Hydroxylated polychlorinated biphenyls are the metabolites produced from parent compounds by the drug‐metabolizing enzyme cytochrome P450. These compounds are suspected to disrupt postembryonic neural development in the brains of mammals including humans. We studied the effects of these compounds on thyroid hormone function in the brain by using metamorphosing tadpoles of the African clawed toad (Xenopus laevis) as a model for mammalian postembryonic development. The metamorphosis assay revealed that these compounds inhibit thyroid hormone‐induced metamorphosis. Genome‐wide gene expression analysis in the brain following short‐term exposure demonstrated that delayed metamorphosis could partially be caused by disruption of thyroid hormone‐induced gene expression. Furthermore, we associated the terms of functional ontology with the genes, whose expression was disrupted by these compounds. We suggest that the use of a genome‐wide analysis coupled with bioinformatics might provide an overview of the molecular mechanism underlying thyroid‐disrupting activities in vivo. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:303–311, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20390
Ornithine decarboxylase prevents dibenzoylmethane‐induced apoptosis through repressing reactive oxygen species generation
Authors: Wu Chih‐Lung , Liao Ya‐Fan , Hung Ying‐Cheng , Lu Ko‐Hsiu , Hung Hui‐Chih , Liu Guang‐Yaw
Published: April 2011

Dibenzoylmethane (DBM) belongs to the flavonoid family and is a minor constituent of the root extract of licorice and the β‐diketone analogue of curcumin. It exhibits antimutagenic, anticancer, and chemopreventive effects. Ornithine decarboxylase (ODC), the rate‐limiting enzyme of the polyamine biosynthetic pathway, plays an important role in growth, proliferation, and transformation. Our previous studies showed ODC overexpression prevented etoposide‐, paclitaxel‐, and cisplatin‐induced apoptosis. Here, we investigated one mechanism of DBM‐induced apoptosis and the antiapoptotic effects of ODC during DBM treatment. We found that DBM induced apoptosis, promoted reactive oxygen species (ROS) generation, and disrupted the mitochondrial membrane potential (Δ ψm. N‐acetylcysteine, a ROS scavenger, reduced DBM‐induced apoptosis, which led to the loss of Δ ψm due to reduced ROS. Overexpression of ODC in parental cells had the same effects as the ROS scavenger. The results demonstrated that DBM‐induced apoptosis was a ROS‐dependent pathway and ODC overexpression blocked DBM‐induced apoptosis by inhibiting intracellular ROS production. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:312–319, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20391
Analytical strategies for assessing comparability of biosimilars
Authors: Falconer Robert J. , Jackson‐Matthews Dianne , Mahler Stephen M.
Published: April 2011

Biosimilar products are required by regulatory authorities to have appropriate and comparable quality, safety and efficacy with a reference biologic product. The analytical techniques that are available to manufacturers of biosimilar medicines are well advanced and present a range of options to characterize the products and compare them with the relevant marketed reference product. This variety of analytical methods can be used to investigate the attributes of a candidate biosimilar and a reference biologic, and ensures that orthogonal methods can be deployed to characterize a single attribute, facilitating rigorous structural characterization and physicochemical evaluation. These analytical methodologies not only enable evidence for bio‐comparability to be amassed but also enable a developer of biosimilars to incorporate risk mitigation into the development strategy. This review discusses the analytical techniques available to support comparability testing, the handling of reference material and the strategic aspects to commercializing biosimilar or follow‐on biological medicinal products. Copyright © 2011 Society of Chemical Industry
Improvement of heat removal in solid‐state fermentation tray bioreactors by forced air convection
Authors: Figueroa‐Montero Arturo , Esparza‐Isunza Tristán , Saucedo‐Castañeda Gerardo , Huerta‐Ochoa Sergio , Gutiérrez‐Rojas Mariano , Favela‐Torres Ernesto
Published: April 2011

BACKGROUND: Heat removal is one of the major constraints in large‐scale solid‐state fermentation (SSF) processes. The effect of internal air circulation by forced convection on heat and water transfer has not been studied in SSF tray bioreactors. Formulation of a mathematical model for SSF requires a good estimation of the mass and heat transfer coefficients.

RESULTS: A stainless steel tray bioreactor (80.6 L capacity) was used. Aspergillus niger C28B25 was cultivated under SSF conditions on an inert support. Temperature, moisture content, biomass and substrate concentrations were measured. Water and energy integral balances were used to estimate the heat and mass transfer coefficients involved in the process. The Reynolds number (NRe) in the headspace of the tray bioreactor ranged from 2.5 to 2839, which increased the global heat transfer coefficient from 4.2 to 6.9 (W m−2 K−1) and the mass transfer coefficient from 1.0 to 2.1 (g m−2 s−1). Mathematical model predictions of the temperature and moisture content of the fermentation bed showed a high goodness‐of‐fit with the experimental results.

CONCLUSIONS: This is the first report describing the effect of NRe of air in the headspace of a SSF tray bioreactor on the heat and mass transfer coefficients and temperature regulation in SSF. Copyright © 2011 Society of Chemical Industry
Linkage for the diamond and the path with four vertices
Authors: Ellingham M. N. , Plummer Michael D. , Yu Gexin
Published: April 2011

Given graphs G and H, we say G is H‐linked if for every injective mapping ℓ: V(H)→V(G), we can find a subgraph H′ of G that is a subdivision of H with ℓ(v) being the vertex of H′ corresponding to each vertex v of H. In this article, we prove two results on H‐linkage for 4‐vertex graphs H. Goddard showed that 4‐connected planar triangulations are 4‐ordered, or in other words C4‐linked. We strengthen this by showing that 4‐connected planar triangulations are (K4−e)‐linked. X. Yu characterized certain graphs related to P4‐linkage. We use his characterization to show that every 7‐connected graph is P4‐linked, and to construct 6‐connected graphs that are not P4‐linked. © 2011 Wiley Periodicals, Inc. J Graph Theory
Synthetic route to isotopically labelled‐oxamate
Authors: Siwek Agata , Trotsko Nazar , Wujec Monika , Kamiński Rafał , Paneth Piotr
Published: April 2011

Since none of the available methods was suitable for the synthesis of isotopically labelled oxamate, a new procedure has been developed in our laboratory, based on the known procedures, but with substantial modifications. The method is convenient and gives reproducibly 17% yield based on KCN used. The strategy is considered suitable for labelling oxamate with 15N and 13C or 14C when starting with labelled KCN and can be easily modified for the synthesis of 18O‐carbonyl‐labelled oxamate. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis of deuterium‐labelled etravirine
Authors: Wang Wei , Wu Wenchao , Shen Zucheng , Chen Liqin
Published: April 2011

This study describes the synthesis of deuterium‐labelled etravirine. Etravirine labelled with six deuteriums was prepared in eight steps starting from phenol with excellent chemical purity and isotopic enrichment. It provides important internal standard for the clinical studies of etravirine. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis of sequentially deuterated 1‐n‐Butyl‐3‐methylimidazolium ionic liquids
Authors: Khrizman Alexander , Cheng Hiu Yan , Moyna Guillermo
Published: April 2011

Deuterium isotopologues of the ionic liquid (IL) 1–n‐butyl‐3‐methylimidazolium chloride ([C4mim]Cl) sequentially labeled on the C‐1″, C‐1′, C‐2′, C‐3′, and C‐4′ positions of the N‐alkyl groups were prepared following a strategy that minimizes the number of distinct reactions through the use of analogous synthetic routes. In several cases, good yields after the initial deuterium incorporation reaction were achieved by combining well‐established chemical transformations into efficient single‐step processes. Copyright © 2011 John Wiley & Sons, Ltd.
A modified approach to C‐14‐labeled 2‐(3,4‐difluorophenoxy)‐5‐fluoronicotinic acid and other halogen‐substituted analogs
Authors: Zhang Yinsheng , Jian Zhigang , Stolle Wayne T.
Published: April 2011

A modified approach to a carbon‐14‐labeled pyridine ring system was developed based on the electrocyclic ring‐closure of 1,4,4‐trisubstituted butadiene. The new method was applied to prepare 2‐(3,4‐difluorophenoxy)‐5‐fluoro‐[2‐14C] nicotinic acid and other halogen‐substituted analogs. The targeted compound was isolated with a radiochemical purity of >98% and a specific activity of 53 mCi/mmol from four radiochemical steps, starting from ethyl [1‐14C] cyanoacetate in an overall radiochemical yield of 39%. Copyright © 2011 John Wiley & Sons, Ltd.
Introduction to the special issue: Terrorism, disaster, and organizational science
Authors: James Keith
Published: April 2011

Here, the editor introduces the special issue on organizations' preparation for and response to disaster and terrorism. The topic and meta‐constructs within it are defined. The papers included in the special issue are outlined. The methodological and conceptual variety and strengths of the new empirical papers are summarized, as are some major gaps in current knowledge and paradigms that became clear from the full set of submissions to the special issue—those that were rejected, as well as those accepted. Together, the papers in this special issue set the stage for potential important future advances in the science of disaster/terrorism preparation and response by organizations. Copyright © 2011 John Wiley & Sons, Ltd.
The psychological contract: What is missing? What is next?
Authors: Joseph Taylere M.
Published: April 2011

Psychological contracts have been linked within organizational behavior literature to employee motivation and productivity. Classically, a psychological contract is defined as “individual beliefs, shaped by the organization, regarding terms of exchange agreement between individuals and their organizational goals” (Rousseau, 2001, p. 2). Recently, psychological contract violations have been identified in the research literature as correlated to employee resistance in system‐wide organizational change, putting change initiatives at risk. Understanding the complex ways that psychological contract violations can induce change resistance highlights the need for organizations to manage the psychological contracts between leadership and employees. Organizations need not only recognize how psychological contracts are formed, but also should heed the need for psychological contracts to be managed. This article reviews what is missing in psychological contract and change management. It then proposes that consultants who are trained in both organizational and individual psychology implement psychological contract management services into their practice.
If I belong, do I believe? An integrative framework for culture and identification
Authors: Bligh Michelle C. , Hatch Mary Jo
Published: April 2011

Organizational culture has become firmly entrenched in the fields of organizational behavior and theory, yet remains a conceptual and methodological challenge for researchers. Because culture involves the processes of sense making, interpretation, and social construction, while identification is more clearly linked theoretically and empirically to attitudes and behavior, bringing these two concepts together helps to address the limits of both. In this article, we develop a multidimensional framework to introduce identification into the discussion of culture, illustrating how tensions of generality–contextuality and unity–multiplicity highlight identification as an important mediator between macrolevel cultural meanings and individual‐level behavioral outcomes. We subsequently explore the framework's potential for integrating disparate approaches and encouraging meso‐level organizational research, arguing that the dual consideration of these concepts may help to elucidate some of the complexities inherent in organizations, as well as focusing attention on the complex influences of both culture and identification in determining organizational outcomes.
Intrinsic and extrinsic motivation and organizational citizenship behavior: A functional approach to organizational citizenship behavior
Authors: Finkelstein Marcia A.
Published: April 2011

This study was the first to link a functional view of organizational citizenship behavior (OCB) to intrinsic and extrinsic motivation. Citizenship behavior and motives were assessed along with motivational orientation and prosocial personality. The results suggest that motives, and the types of OCB they foster, derive in part from individual differences in motivational orientation. Intrinsically motivated individuals manifested internal, other‐oriented motives for OCB, while those with extrinsic orientations were driven largely by external, self‐focused objectives. Mediation analyses implicated motivational orientation as a causal factor in determining specific motives. Citizenship activities directed at coworkers also showed a strong relationship with prosocial personality. A strong, positive correlation between intrinsic and extrinsic motivation suggested the usefulness of viewing them as complementary rather than competing tendencies, working together to help individuals accomplish a goal. The data further highlight the efficacy of a functional approach to understanding a broad spectrum of prosocial actions.
Transformation, emotional intelligence, and brain science
Authors: Hernez‐Broome Gina
Published: April 2011

Mindsight: The New Science of Personal Transformation

By Daniel J. Siegel

New York: Bantam Books, 2010. 316 pp. ISBN: 978‐0‐553‐80470‐6. $24.99
The relationship between posttraumatic stress disorder and smoking outcome expectancies among U.S. military veterans who served since September 11, 2001
Authors: Calhoun Patrick S. , Levin Holly F. , Dedert Eric A. , Johnson Yashika ,   The VA Mid‐Atlantic Mental Illness Research, Education, Clinical Center Registry Workgroup, Beckham Jean C.
Published: April 2011

Posttraumatic stress disorder (PTSD) is associated with increased rates of smoking although little is known regarding the mechanisms underlying this relationship. The current study examined expectations about smoking outcomes among smokers with and without PTSD. The sample included 96 veterans (mean age of 34 years) and included 17% women and 50% racial minorities. Smoking expectancies were measured with the Smoking Consequences Questionnaire‐Adult (Copeland, Brandon, & Quinn, 1995). Consistent with previous work suggesting that smokers with PTSD smoke in an effort to reduce negative affect, unadjusted analyses indicated that smokers with PTSD (n = 38) had higher expectations that smoking reduces negative affect than smokers without PTSD (d = 0.61). Smokers with PTSD also had increased expectancies associated with boredom reduction (d = 0.48), stimulation (d = 0.61), taste/sensorimotor manipulation aspects of smoking (d = 0.73), and social facilitation (d = 0.61). Results of hierarchical linear regression analyses indicated that PTSD symptom severity was uniquely associated with these expectancies beyond the effects of gender and nicotine dependence. More positive beliefs about the consequences of smoking may increase risk of continued smoking among those with PTSD who smoke. Further understanding of smoking expectancies in this group may help in developing interventions tailored for this vulnerable population.
The bipedicled anterior septal flap
Authors: Bleier Benjamin S. , Curry William T. , Wang Eric W. , Schlosser Rodney J.
Published: April 2011

Objectives/Hypothesis:

Pedicled mucosal flaps are the preferred method of endoscopic skull base reconstruction. Vascularized coverage of the anterior and posterior frontal tables remains a challenge given the lack of large caliber vessels supplying the anterior septum. The objective of this study was to define a novel bipedicled anterior septal (BAS) flap that is hypothesized to be capable of providing reproducible coverage of these difficult areas.

Study Design:

Radioanatomic and cadaveric study.

Methods:

The flap outline was superimposed over nine midline sagittal computed tomography images. The pedicles are comprised of the septal branch of the superior labial artery and the nasopalatine artery. The flap length subtended the distance from the incisive canal to the sphenoid face at the level of the choanal arch. Radiometric analysis of the flap length to base ratio and anterior/posterior frontal table coverage were calculated. These projected values were confirmed in four cadaveric dissection specimens.

Results:

The mean flap length was 39.64 ± 4.26 mm with a mean length:base ratio of 3.29 ± 0.70 and a total surface area of 916.46 ± 262.66 mm2. The flap was estimated to provide coverage of 100.31± 21.34% of the frontal beak and 50.74 ± 32.54% of the posterior frontal table. In all cadaveric specimens the flap extended beyond the superior aspect of the frontal beak and at least 50% of the posterior table.

Conclusions:

The BAS flap represents a novel septal mucosal flap based on two well‐defined arterial inputs. This flap is capable of providing reliable vascularized coverage of the posterior frontal table and the frontal beak following frontal drillout.
Systematic review and meta‐analyses of randomized controlled trials examining tinnitus management
Authors: Hoare Derek J. , Kowalkowski Victoria L. , Kang Sujin , Hall Deborah A.
Published: April 2011

Objectives/Hypothesis:

To evaluate the existing level of evidence for tinnitus management strategies identified in the UK Department of Health's Good Practice Guideline.

Study Design:

Systematic review of peer‐reviewed literature and meta‐analyses.

Methods:

Searches were conducted in PubMed, Cambridge Scientific Abstracts, Web of Science, and EMBASE (earliest to August 2010), supplemented by hand searches in October 2010. Only randomized controlled trials that used validated questionnaire measures of symptoms (i.e., measures of tinnitus distress, anxiety, depression) were included.

Results:

Twenty‐eight randomized controlled trials met our inclusion criteria, most of which provide moderate levels of evidence for the effects they reported. Levels of evidence were generally limited by the lack of blinding, lack of power calculations, and incomplete data reporting in these studies. Only studies examining cognitive behavioral therapy were numerous and similar enough to perform meta‐analysis, from which the efficacy of cognitive behavioral therapy (moderate effect size) appears to be reasonably established. Antidepressants were the only drug class to show any evidence of potential benefit.

Conclusions:

The efficacy of most interventions for tinnitus benefit remains to be demonstrated conclusively. In particular, high‐level assessment of the benefit derived from those interventions most commonly used in practice, namely hearing aids, maskers, and tinnitus retraining therapy needs to be performed.
New Method for Real‐time Monitoring of Photopolymerization by UV–Vis Spectroscopy
Authors: Schmitt Michael
Published: April 2011

A new technology to measure the kinetics of bulk radical polymerization is presented. This technology is easy to connect with all systems using irradiation light, including Raman and IR measurement setups. The curing kinetics of commercially available offset printing dyes (acrylic esters) with initiators have been studied in situ in real‐time by light transmission. The setup consists of a slightly modified diode array UV–Vis spectrometer with a dual purpose xenon arc flash lamp light source. The lateral dependency (irradiation dosage) of the change in the transmitted light has the potential to be interesting for scientific and industrial applications. In addition, options for kinetics studies and quantum efficiencies are introduced to expand the possibilities of studying the polymerization processes.

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Fluorescent Vesicles Consisting of Galactose‐based Amphiphilic Copolymers with a π‐Conjugated Sequence Self‐assembled in Water
Authors: Aissou Karim , Pfaff André , Giacomelli Cristiano , Travelet Christophe , Müller Axel H.E. , Borsali Redouane
Published: April 2011

Fluorescent vesicles considered as a mimic of natural primitive cells are prepared from poly(3‐hexylthiophene)‐block‐poly(3‐O‐methacryloyl‐D‐galactopyranose) P3HT‐b‐PMAGP copolymers. The unique characteristic of such vesicular nanostructures is their architecture, which comprises a hydrophobic π‐conjugated P3HT wall stabilized by a hydrophilic PMAGP interface featuring glucose units. The results of this work offer a very efficient and straightforward method for engineering well‐controlled fluorescent nanoparticles (without the addition of dyes), which provide an excellent support to the study of carbohydrate‐protein interactions.

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Direct Synthesis of Biodegradable Polysaccharide Derivative Hydrogels Through Aqueous Diels‐Alder Chemistry
Authors: Tan Huaping , Rubin J. Peter , Marra Kacey G.
Published: April 2011

A robust synthetic strategy where polysaccharide derivative precursors react through aqueous Diels–Alder chemistry without the involvement of catalysts and coupling reagents, allowing for the direct encapsulation of positive and negative proteins within biodegradable hydrogels. The results demonstrated that the aqueous Diels–Alder chemistry provides an extremely selective reaction and proceeds with high efficiency for polysaccharide bioconjugation. This synthetic approach uniquely allows for the direct fabrication of biologically functionalized gels with ideal structures, which provides a competitive alternative to conventional conjugation techniques such as click chemistry.

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Appetitive motivational deficits in individuals with Parkinson's Disease
Authors: Shore Danielle M. , Rafal Robert , Parkinson John A.
Published: April 2011

Parkinson's disease is known for its effects on sensorimotor coordination caused by degeneration of the nigrostriatal dopamine pathway. Dopamine‐innervated areas of the ventral striatum also become compromised in Parkinson's disease, and little is known about the potential impact of this pathology on motivational processes mediated by the mesolimbic dopamine system. The current study tested the hypothesis that patients with Parkinson's disease would show a deficit in appetitive motivational arousal. Patients with Parkinson's disease and age‐matched healthy controls completed a visual discrimination task in which control and appetitive food images (incidental to the task) were presented in the background. Response rate changes indicated appetitive motivational arousal. The healthy controls showed an increase in response rate on the task when appetitive food cues were present compared with control stimuli. In contrast, the Parkinson's disease group showed an inverse pattern to the healthy controls. The reduction in appetitive motivation correlated with an individual's Parkinsonian symptomology. Patients with Parkinson's disease demonstrated an impairment in appetitive motivational arousal consistent with the progression of dopaminergic degeneration across the course of the disease. Dysfunction of this system affects quality of life in Parkinson's disease, and a blunting of the anticipatory motivation may contribute to the high prevalence of depression in Parkinson's disease. © 2011 Movement Disorder Society
Nerve sparing‐distally based sural flap
Authors: Aydin Osman E. , Tan Onder , Kuduban Selma D. , Barin Ensar Z.
Published: April 2011

The management of soft‐tissue defects in the ankle and foot area is a challenging task. Distally based sural flap is widely used, however it leaves donor area paresthesia. For this purpose, the sural nerve was dissected and preserved in the distally based sural flap in five cases of ankle and foot soft tissue reconstruction. This modification did not cause any compromise in flap circulation. All flaps survived with one partial distal necrosis. We suggest that, the distally based nerve sparing sural flap can be securely elevated with only a 3–4 cm wide subcutaneous pedicle without any compromise in flap circulation. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
High‐pressure treatment reduces the immunoreactivity of the major allergens in apple and celeriac
Authors: Husband Fiona A. , Aldick Thomas , Van der Plancken Iesel , Grauwet Tara , Hendrickx Marc , Skypala Isabel , Mackie Alan R.
Published: April 2011

Scope: The impact of thermal and high pressure (HP) processing on the immunoreactivity of the allergens Mal d 1, Mal d 3 and Api g 1 has been investigated in apple and celeriac tissue, respectively.

Methods and results: The extracted proteins were assessed using SDS‐PAGE and Western blot. The results showed that Mal d 1 was subject to loss of immunoreactivity as soon as the apple tissue was disrupted although it was remarkably resistant to both thermal and HP processing. This is in contrast to the Mal d 1 structural homolog from celeriac, Api g 1, that was susceptible to thermal processing. The other major allergen in apple, Mal d 3, was found to be resistant to chemical modification and thermal processing in apple, which is in contrast to behavior in solution. However, the combination of pressure and temperature significantly reduced its immunoreactivity. Pectin was found to protect Mal d 3 from thermal denaturation in solution and is a possible candidate for the protective effect of the fruit.

Conclusion: The conclusion to be drawn from these results is that the combination of HP and thermal processing is an effective method to reduce the allergenicity of both apple and celeriac.
Resveratrol (trans‐3,5,4′‐trihydroxystilbene) suppresses EL4 tumor growth by induction of apoptosis involving reciprocal regulation of SIRT1 and NF‐κB
Authors: Singh Narendra P. , Singh Udai P. , Hegde Venkatesh L. , Guan Hongbing , Hofseth Lorne , Nagarkatti Mitzi , Nagarkatti Prakash S.
Published: April 2011

Scope: Understanding the molecular mechanisms through which natural products and dietary supplements exhibit anticancer properties is crucial and can lead to drug discovery and chemoprevention. The current study sheds new light on the mode of action of resveratrol (RES), a plant‐derived polyphenolic compound, against EL‐4 lymphoma growth.

Methods and results: Immuno‐compromised NOD/SCID mice injected with EL‐4 tumor cells and treated with RES (100 mg/kg body weight) showed delayed development and progression of tumor growth and increased mean survival time. RES caused apoptosis in EL4 cells through activation of aryl hydrocarbon receptor (AhR) and upregulation of Fas and FasL expression in vitro. Blocking of RES‐induced apoptosis in EL4 cells by FasL mAb, cleavage of caspases and PARP, and release of cytochorme c, demonstrated the participation of both extrinsic and intrinsic pathways of apoptosis. RES also induced upregulation of silent mating type information regulation 2 homolog, 1 (SIRT1) and downregulation of nuclear factor kappa B (NF‐κB) in EL4 cells. siRNA‐mediated downregulation of SIRT1 in EL4 cells increased the activation of NF‐κB but decreased RES‐mediated apoptosis, indicating the critical role of SIRT1 in apoptosis via blocking activation of NF‐κB.

Conclusion: These data suggest that RES‐induced SIRT1 upregulation promotes tumor cell apoptosis through negative regulation of NF‐κB, leading to suppression of tumor growth.
Effect of supplementation with vitamin D3 on glucose production pathways in human subjects
Authors: O'Sullivan Aifric , Balducci Daniele , Paradisi Francesca , Cashman Kevin D. , Gibney Michael J. , Brennan Lorraine
Published: April 2011

Scope: Research reports suggest that vitamin D affects glucose and insulin metabolism; however, the exact mechanisms are unclear. 2H NMR analysis of monoacetone glucose (MAG) after tracer administration provides a non‐invasive method of profiling hepatic glucose metabolism. This study examined the effects of supplementation with vitamin D3 on contribution of glycogenolysis to glucose production.

Methods and results: Tracer administration and biofluid collections were performed with eight healthy females before and following a 4‐wk vitamin D3 administration period. Following an overnight fast subjects ingested deuterated water and acetaminophen. Full void urine samples were collected after 4 h. 2H NMR spectra of urinary monoacetone glucose were acquired to determine the contribution of glycogenolysis to glucose production. The mean contribution of glycogenolysis to glucose production was 60±13%. Supplementation with vitamin D3 had no effect on hepatic glucose production. Regression analysis revealed a significant relationship between carbohydrate intake and the contribution of glycogenolysis (β=0.914, p=0.004).

Conclusion: In conclusion, we saw no changes in the percentage contribution of glycogenolysis following supplementation with vitamin D3. The reproducibility of our results and the non‐invasive nature of the method highlight the potential for this method in assessing mechanistic modes of action in future nutritional interventions.
Tutorial on physiologically based kinetic modeling in molecular nutrition and food research
Authors: Rietjens Ivonne M. C. M. , Louisse Jochem , Punt Ans
Published: April 2011

Studies in the field of molecular nutrition and food research often aim at identifying effects of bioactive ingredients on living organisms. When data from human studies are difficult to obtain, effects are often studied in relevant animal or cellular in vitro models. This poses the need for adequate extrapolation from the in vitro to the in vivo situation, from high‐dose levels to realistic low‐dose levels and from experimental animals to humans. Furthermore, effects of genetic polymorphisms or lifestyle factors may have to be taken into account. Physiologically based kinetic (PBK) modeling provides a means to support these kinds of extrapolations. The present paper illustrates the basic concepts of PBK modeling. PBK modeling includes six steps: (i) definition of the conceptual model, (ii) translation into a mathematical model, (iii) defining parameter values, (iv) solving the equations, (v) evaluation of model performance and (vi) making predictions. The paper provides an overview of these basic steps and presents examples to illustrate how PBK modeling can be applied. This reveals that PBK modeling provides an important tool in the field of the 3Rs aiming at Replacement, Reduction and Refinement of animal studies and may also be a useful tool for risk assessment.
Combined use of T2‐weighted MRI and T1‐weighted dynamic contrast–enhanced MRI in the automated analysis of breast lesions
Authors: Bhooshan Neha , Giger Maryellen , Lan Li , Li Hui , Marquez Angelica , Shimauchi Akiko , Newstead Gillian M.
Published: April 2011

A multiparametric computer‐aided diagnosis scheme that combines information from T1‐weighted dynamic contrast–enhanced (DCE)‐MRI and T2‐weighted MRI was investigated using a database of 110 malignant and 86 benign breast lesions. Automatic lesion segmentation was performed, and three categories of lesion features (geometric, T1‐weighted DCE, and T2‐weighted) were automatically extracted. Stepwise feature selection was performed considering only geometric features, only T1‐weighted DCE features, only T2‐weighted features, and all features. Features were merged with Bayesian artificial neural networks, and diagnostic performance was evaluated by ROC analysis. With leave‐one‐lesion‐out cross‐validation, an area under the ROC curve value of 0.77 ± 0.03 was achieved with T2‐weighted‐only features, indicating high diagnostic value of information in T2‐weighted images. Area under the ROC curve values of 0.79 ± 0.03 and 0.80 ± 0.03 were obtained for geometric‐only features and T1‐weighted DCE‐only features, respectively. When all features were considered, an area under the ROC curve value of 0.85 ± 0.03 was achieved. We observed P values of 0.006, 0.023, and 0.0014 between the geometric‐only, T1‐weighted DCE‐only, and T2‐weighted‐only features and all features conditions, respectively. When ranked, the P values satisfied the Holm–Bonferroni multiple‐comparison test; thus, the improvement of multiparametric computer‐aided diagnosis was statistically significant. A computer‐aided diagnosis scheme that combines information from T1‐weighted DCE and T2‐weighted MRI may be advantageous over conventional T1‐weighted DCE‐MRI computer‐aided diagnosis. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Signal‐to‐noise ratio for hyperpolarized 3He MR imaging of human lungs: A 1.5 T and 3 T comparison
Authors: Dominguez‐Viqueira William , Ouriadov Alexei , O'Halloran Rafael , Fain Sean B. , Santyr Giles E.
Published: April 2011

The signal‐to‐noise ratio in hyperpolarized noble gas MR imaging is expected to be independent of field strength at frequencies typical of clinical systems (e.g., 1.5 T), where body noise dominates over coil noise. Furthermore, at higher fields (e.g., 3 T), the SNR of lung images may decline due to decreases in T2* originating from increases in susceptibility‐induced field gradients at the air‐tissue interface. In this work, the SNR of hyperpolarized 3He lung imaging at two commonly used clinical field strengths (1.5 T and 3 T) were compared in the same volunteers. Thermally polarized and hyperpolarized 3He phantoms were used to account for differences in MR imaging system and 3He polarizer performance, respectively, at the two field strengths. After correcting for T2* values measured at 1.5 T (16 ± 2 ms) and 3 T (7 ± 1 ms), no significant difference in image SNR between the two field strengths was observed, consistent with theory. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Use of respiratory biofeedback and CLAWS for increased navigator efficiency for imaging the thoracic aorta
Authors: Jhooti P. , Haas T. , Kawel N. , Bremerich J. , Keegan J. , Scheffler K.
Published: April 2011

A novel technique to guide a subjects' breathing pattern using a respiratory biofeedback (rBF) “game” to improve respiratory efficiency is presented. The continuously adaptive windowing strategy, a fully automatic and highly efficient free‐breathing navigator gated technique, is used to acquire the data as it ensures that all potential navigator acceptance windows are possible. This enables the rBF to be fully adaptable to a subject's respiratory pattern. Images of the thoracic aorta acquired using balanced steady‐state free precession with continuously adaptive windowing strategy respiratory motion control, with and without rBF, were compared in 10 healthy subjects. Total scan time was reduced by using rBF. The mean scan time was reduced from 7 min 44 s (463 cardiac cycles, ±127cc) without rBF to 5 min 43 s (380 cardiac cycles, ±118cc) with the use of rBF (P < 0.05). Respiratory efficiency was increased from 45% without rBF to 56% with rBF (P < 0.01). Image quality was the same for both techniques (P = ns). In conclusion, rBF significantly improved respiratory efficiency and reduced acquisition duration without affecting image quality. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Improved temporal resolution in cardiac imaging using through‐time spiral GRAPPA
Authors: Seiberlich Nicole , Lee Gregory , Ehses Philipp , Duerk Jeffrey L. , Gilkeson Robert , Griswold Mark
Published: April 2011

Previous work has shown that the use of radial GRAPPA for the reconstruction of undersampled real‐time free‐breathing cardiac data allows for frame rates of up to 30 images/s. It is well known that the spiral trajectory offers a higher scan efficiency compared to radial trajectories. For this reason, we have developed a novel through‐time spiral GRAPPA method and demonstrate its application to real‐time cardiac imaging. By moving from the radial trajectory to the spiral trajectory, the temporal resolution can be further improved at lower acceleration factors compared to radial GRAPPA. In addition, the image quality is improved compared to those generated using the radial trajectory due to the lower acceleration factor. Here, we show that 2D frame rates of up to 56 images/s can be achieved using this parallel imaging method with the spiral trajectory. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Sensitivity calibration with a uniform magnetization image to improve arterial spin labeling perfusion quantification
Authors: Dai Weiying , Robson Philip M. , Shankaranarayanan Ajit , Alsop David C.
Published: April 2011

Quantification of perfusion with arterial spin labeling MRI requires a calibration of the imaging sensitivity to water throughout the imaged volume. Since this sensitivity is affected by coil loading and other interactions between the subject and the scanner, the sensitivity must be calibrated in the subject at the time of scan. Conventional arterial spin labeling perfusion quantification assumes a uniform proton density and acquires a proton density reference image to serve as the calibration. This assumption, in the form of an assumed constant brain‐blood partition coefficient, incorrectly adds inverse proton density weighting to the perfusion image. Here, a sensitivity calibration is proposed by generating a uniform magnetization image whose intensity is highly independent of brain tissue type. It is shown that such a uniform magnetization image can be achieved, and brain tissue perfusion values quantified with the sensitivity calibration agree with those quantified with a proton density image when segmentation of brain tissues is performed and appropriate partition coefficients are assumed. Quantification of brain tissue water density is also demonstrated using this sensitivity calibration. This approach can improve and simplify quantification of arterial spin labeling perfusion and may have broader applications to measurement of edema and sensitivity calibration for parallel imaging. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.