bluuebunny/crossref_metadata_2025 huggingface dataset:
Heterophase states and a bridging phase in (1‐x)BiScO3 − xPbTiO3
Authors: Topolov V. Yu.
Published: July 2012

Heterophase ferroelectric solid solutions of (1‐x)BiScO3 − xPbTiO3 are studied near the morphotrpic phase boundary (0.60 ≤ x ≤ 0.64). The role of non‐180° domain types of the P4mm and R3m phases in heterophase structures is studied in the context of the phase content. It is shown that the bridging Cm phase coexists with the adjacent phase (either P4mm or R3m), and different variants of an elastic matching ‘single‐domain Cm phase–polydomain P4mm phase’, ‘single‐domain Cm phase–polydomain R3m phase’ and ‘single‐domain Cm phase–near single‐domain R3m phase’ promote the complete stress relief. Based on these concepts and considering a minimum number of the domain types in the coexisting phases, we find a molar‐concentration dependence of the volume fraction of the Cm phase in the heterophase states. A correlation between the predicted volume fraction of the Cm phase and ratios of its unit‐cell parameters is first revealed. The role of the intermediate R3m phase in the phase sequence R3c − R3m − Pm\documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\overline 3$\end{document}m and in the stress relief at x = 0.60 is discussed. Good agreement between the predicted and experimental data on the phase content is reached near the morphotrpic phase boundary.
Selective Conversion of Furfural to Maleic Anhydride and Furan with VOx/Al2O3 Catalysts
Authors: Alonso‐Fagúndez Noelia , Granados Manuel López , Mariscal Rafael , Ojeda Manuel
Published: July 2012

Furfural can be converted into maleic anhydride (73 % yield) through selective gas phase oxidation at 593 K with O2 by using VOx/Al2O3 (10 atV nm−2) as solid catalysts. The use of lower temperatures and/or O2 pressures result in the additional formation of furan (maximum 9 % yield). Mechanistically, furfural (C5H4O2) is oxidized stepwise to furan (C4H4O), 2‐furanone (C4H4O2), and finally, maleic anhydride (C4H2O3). The specific structure of the supported vanadium oxides and reaction conditions (temperature and reactants pressures) all influence furfural oxidation catalysis. We have found that Al2O3‐supported polyvanadates are intrinsically more active (2.70 mmol h−1 g‐at V−1) than monovanadates (VO4) and V2O5 crystals (0.89 and 0.70 mmol h−1 g‐at V−1, respectively) in maleic anhydride and furan formation rates (553 K, 1.6 kPa furfural, 2.5 kPa O2). Our alternative approach enables the use of biomass instead of petroleum to synthesize maleic anhydride and furan from furfural. The potential variety of industrial applications is of enormous interest for the development of future biorefineries.
Nicotinamide‐Dependent Ene Reductases as Alternative Biocatalysts for the Reduction of Activated Alkenes
Authors: Durchschein Katharina , Wallner Silvia , Macheroux Peter , Schwab Wilfried , Winkler Thorsten , Kreis Wolfgang , Faber Kurt
Published: July 2012

Four NAD(P)H‐dependent non‐flavin ene reductases have been investigated for their ability to reduce activated C=C bonds in an asymmetric fashion by using 20 structurally diverse substrates. In comparison with flavin‐dependent Old Yellow Enzyme homologues, a higher degree of electronic activation was required, because the best activities were obtained with enals and nitroalkenes rather than enones and carboxylic esters. Although FaEO from Fragaria x ananassa (strawberry) and its homologue SlEO from Solanum lycopersicum (tomato) exhibited a narrow substrate spectrum, progesterone 5β‐reductase (At5β‐StR) from Arabidopsis thaliana (thale cress) and leukotriene B4 12‐hydroxydehydrogenase (LTB4DH/PGR) from Rattus norvegicus (rat) appear to be promising candidates, in particular for the asymmetric bioreduction of open‐chain enals, nitroalkenes and α,β‐unsaturated γ‐butyrolactones. Competing nitro reduction and non‐enzymatic Weitz–Scheffer epoxidation were largely suppressed.
Application of the buccal micronucleus cytome assay and analysis of PON1Gln192Arg and CYP2A6*9(−48T>G) polymorphisms in tobacco farmers
Authors: Da Silva Fernanda Rabaioli , Da Silva Juliana , Nunes Emilene , Benedetti Danieli , Kahl Vivian , Rohr Paula , Abreu Marina B. , Thiesen Flávia Valladão , Kvitko Kátia
Published: July 2012

Tobacco is a major Brazilian cash crop. Tobacco farmers apply large amounts of pesticides to control insect growth. Workers come into contact with green tobacco leaves during the tobacco harvest and absorb nicotine through the skin. In the present study, micronucleus frequency, cell death, and the frequency of basal cells were measured in tobacco farmers using the buccal micronucleus cytome assay (BMCyt), in parallel with measurement of blood butyrylcholinesterase (BChE) and nicotine levels. Polymorphisms in PONIGln192Arg and CYP2A6*9(−48T>G) were evaluated to verify the relationship between genetic susceptibility and the measured biomarkers. Peripheral blood and buccal cell samples were collected from 106 agricultural workers, at two different crop times (during pesticide application and leaf harvest), as well as 53 unexposed controls. BMCyt showed statistically significant increases in micronuclei, nuclear buds, and binucleated cells among exposed subjects in differentiated cells, and in micronuclei in basal cells. In addition, the exposed group showed higher values for condensed chromatin, karyorrhectic, pyknotic, and karyolitic cells, indicative of cell death, and an increase in the frequency of basal cells compared to the unexposed control group. A slight difference in mutagenicity using the BMCyt assay was found between the two different sampling times (pesticide application and leaf harvest), with higher micronucleus frequencies during pesticide application. Elevated cotinine levels were observed during the leaf harvest compared to the unexposed controls, while BChE level was similar among the farmers and controls. PONIGln192Arg and CYP2A6*9(−48T>G) polymorphisms were associated with DNA damage induced by pesticides and cell death. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.
Bixin and norbixin protect against DNA‐damage and alterations of redox status induced by methylmercury exposure in vivo
Authors: Barcelos Gustavo Rafael Mazzaron , Grotto Denise , Serpeloni Juliana Mara , Aissa Alexandre Ferro , Antunes Lusânia Maria Greggi , Knasmüller Siegfried , Barbosa Fernando
Published: July 2012

Populations in the Amazon are exposed to organic mercury via consumption of contaminated foods. These ethnic groups consume a specific plant seed “annatto” which contains certain carotenoids. The aim of this study was to find out if these compounds (bixin, BIX and norbixin, NOR), protect against DNA‐damage caused by the metal. Therefore, rats were treated orally with methylmercury (MeHg) and with the carotenoids under conditions that are relevant to humans. The animals were treated either with MeHg (30 μg/kg/bw/day), BIX (0.1–10 mg/kg/bw/day), NOR (0.01–1.0 mg/kg/bw/day) or combinations of the metal compound and the carotenoids consecutively for 45 days. Subsequently, the glutathione levels (GSH) and the activity of catalase were determined, and DNA‐damage was measured in hepatocytes and leukocytes using single cell gel electrophoresis assays. Treatment with the metal alone caused a decrease in the GSH levels (35%) and induced DNA damage, which resulted in increased DNA migration after electrophoresis in liver and blood cells, whereas no effects were seen with the carotenoids alone. When BIX or NOR were given in combination with organic mercury, the intermediate and the highest concentrations of the carotenoids (1.0 and 10.0 mg/kg/bw/day BIX and 0.1 and 1.0 mg/kg/bw/day NOR) protected against DNA‐damage. Furthermore, we found with both carotenoids, a moderate increase in the GSH levels in both metal‐treated and untreated animals, while the activities of catalase remained unchanged. Our results indicate that consumption of BIX and NOR may protect humans against the adverse health effects caused by exposure to organic mercury. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.
DSM‐IV‐Defined Anorexia Nervosa Versus Subthreshold Anorexia Nervosa (EDNOS‐AN)
Authors: Le Grange Daniel , Crosby Ross D. , Engel Scott G. , Cao Li , Ndungu Alfred , Crow Scott J. , Peterson Carol B. , Mitchell James E. , Wonderlich Stephen A.
Published: July 2012

Objectives

Eating disorder not otherwise specified (EDNOS) is the most prevalent eating disorder, yet its heterogeneity begs less reliance on this broad diagnostic category. The purpose of this study was to compare women with anorexia nervosa (AN) and EDNOS, AN type (EDNOS‐AN) from a multisite study on eating‐related and general psychopathology measures.

Methods

One hundred eighteen participants (n = 59 with DSM‐IV AN, n = 59 with EDNOS‐AN) completed structured interviews, questionnaires and a physical examination at baseline. In addition, participants carried a handheld palm pilot computer for 2 weeks to provide ecological momentary assessment (EMA) information about mood and eating disorder behaviours.

Results

No significant differences between AN and EDNOS‐AN were found on the self‐report and interview measures, or on the EMA mood assessments. The only differences to emerge were that participants with AN reported higher rates of binge eating and purging on EMA compared with those with EDNOS‐AN, whereas EDNOS‐AN reported higher rates of checking thighs and joints on EMA compared with those with AN. For the physiological parameters, AN presented with lower white blood cell counts compared with EDNOS‐AN.

Conclusions

Findings highlight the clinical significance of EDNOS‐AN and support a closer look at the definition of AN as proposed by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Factors affecting spatial variation of polycyclic aromatic hydrocarbons in surface soils in North China Plain
Authors: Wang Xilong , Zuo Qian , Duan Yonghong , Liu Wenxin , Cao Jun , Tao Shu
Published: July 2012

The spatial variation in concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in surface soils in the North China Plain and the influential factors were examined in the present study. High concentrations of the sum of 16 PAHs (∑PAH16) appeared in cities and their surrounding areas. Emissions and soil organic carbon (SOC) content significantly regulated spatial differentiation of PAH contamination in soils in the study area. Compared with emissions, concentrations of individual and total PAHs in soils were more closely controlled by the SOC content. Furthermore, concentrations of PAH species with lower molecular weight (e.g., two- or three-ring) in surface soils were more strongly correlated with the SOC content in comparison with those of higher molecular weight (e.g., five- or six-ring), mainly because of their higher saturated vapor pressure, thus higher mobility. The spatial variation of PAH species in soils in the North China Plain tended to be larger with increasing benzene ring numbers, and the difference in physicochemical properties of PAH species determined their distinct spatial distribution characteristics. The present study highlights the relative importance of emissions and SOC content in spatial variation of PAHs and the dependence of the spatial distribution characteristics of PAH species in surface soils on their physicochemical properties at a regional scale. Results of the present work are helpful for regional risk assessment of the contaminants tested. Environ. Toxicol. Chem. 2012; 31: 2246–2252. © 2012 SETAC
Quantum dot nanoparticles affect the reproductive system of Caenorhabditis elegans
Authors: Hsu Pei-Chun L. , O'Callaghan Maureen , Al-Salim Najeh , Hurst Mark R. H.
Published: July 2012

Quantum dots (QDs) are an increasingly important class of nanoparticle, but little ecotoxicological data for QDs has been published to date. The effects of mercaptosuccinic acid (MSA)-capped QDs (QDs-MSA) and equivalent concentrations of cadmium (Cd) from cadmium chloride on growth and reproduction of the nematode Caenorhabditis elegans (Rhabditidae) were assessed in laboratory experiments. Growth from larvae to adults of C. elegans was unaffected by exposure to 1 µM fluorescent QDs-MSA, but adults produced more embryos and laid them prematurely. Furthermore, C. elegans exposed to QDs-MSA (1 µM) showed a high percentage of embryo mortality (19.2 ± 0.5, p < 0.001, percentage ± standard deviation) compared with unexposed nematodes (11.6 ± 0.4). An egg-laying defect phenotype was also observed at high frequency in response to 1 µM QDs-MSA exposure (38.3 ± 3.6%, p < 0.01; control 10.0 ± 2.2%). This resulted in a reduced mean life span (20.5 ± 1.1 d, p < 0.05) compared with the control (24.6 ± 1.0 d). Cadmium also caused reduced life span in C. elegans, but a low incidence of egg-laying defects was observed, suggesting that Cd and QDs-MSA affected C. elegans by different mechanisms. Furthermore, egg-laying defects caused by QDs-MSA responded to the addition of the anticonvulsant ethosuximide and to a lesser extent to the neurotransmitter serotonin, suggesting that QDs-MSA might have disrupted motor neurons during the reproduction process. Environ. Toxicol. Chem. 2012; 31: 2366–2374. © 2012 SETAC
Effectiveness of a recovery‐orientated psychiatric intervention package on the wellbeing of people with early dementia: a preliminary randomised controlled trial
Authors: Jha Arun , Jan Farida , Gale Tim , Newman Charmaine
Published: July 2012

Objective

To investigate whether recovery‐orientated psychiatric assessment and therapeutic intervention enhances the wellbeing of people with dementia and their family carers.

Methods

In a preliminary randomised controlled trial, 48 people with early dementia were recruited. Of 34 who completed the trial, 17 were in the recovery and 17 in the treatment as usual group. Recovery participants received a recovery‐focused pre‐diagnostic wellbeing assessment and counselling, diagnostic consultation with written feedback and post‐diagnostic support over a period of 6 months using the WHO Wellbeing Index as the primary measure, and Mini Mental State Examination, Cornell Scale for Depression in Dementia, EUROQOL and Zarit Burden Interview as secondary outcome measures.

Results

People in the recovery group showed a significant improvement in the WHO Wellbeing Index (18.3 for recovery vs 9.46 for treatment as usual; t = −2.28, p = 0.03), with trends of improvement in other outcome measures.

Conclusions

This trial shows that a recovery‐focused diagnostic consultation and post‐diagnostic support enhance the wellbeing of people with mild cognitive impairment and early dementia. Copyright © 2012 John Wiley & Sons, Ltd.
Surgical management of bilateral parotid lipomatosis in a patient with HIV
Authors: Cunningham Aileen L. , Taghi Ali S. , Singh Gurmit Kaur Jagjit , Sandison Ann , Cohen Charlotte E. , Grant William E.
Published: July 2012

Background

The long‐term use of highly active antiretroviral therapy (HAART) in patients with human immunodeficiency virus (HIV) has led to sequelae including lipodystrophy syndrome (LDS). We present the first published case of surgical management of bilateral parotid lipomatosis in a patient with HIV on long‐term HAART.

Methods

We undertook review of the case notes from the time of diagnosis with HIV and literature review of this topic.

Results

A 45‐year‐old man with HIV on HAART presented with a 4‐year history of increasing bilateral facial swelling. He was asymptomatic apart from the stigmatizing cosmetic deformity. MRI revealed the parotid glands had been replaced by fat. He elected for surgery and parotid lipomatosis was diagnosed on histopathological examination.

Conclusion

Lipohypertrophy in LDS is rare in the literature and this presentation of bilateral parotid lipomatosis secondary to HAART is only the third reported case, and the first to undergo surgical resection. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
An experimental investigation on the free convection heat transfer in a horizontal cavity consisting of flow diverters
Authors: Yousefi Tooraj , Karami Alimohammad , Ghashghaei Damoon , Veysi Farzad
Published: July 2012

The free convection heat transfer in a horizontal cavity with adiabatic vertical and isothermally horizontal walls and adiabatic diverters has been studied experimentally in this paper. The experiments have been carried out using a Mach–Zehnder interferometer. The effects of the diverter angle ranging from 0 to 90$\circ$ and Rayleigh number based on the cavity side wall length, from 6 × 103 to 1.2 × 104 on the heat transfer from the heated wall, were studied. The results indicate that, at each Rayleigh number, the maximum and the minimum heat transfer occur at a diverter angle of 30 and 90$\circ$, respectively. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21014
Heat and mass transfer in a MHD non‐Darcian micropolar fluid over an unsteady stretching sheet with non‐uniform heat source/sink and thermophoresis
Authors: Aurangzaib  , Shafie Sharidan
Published: July 2012

The effect of heat and mass transfer in a MHD non‐Darcian flow of a micropolar fluid over an unsteady stretching sheet with thermophoresis and non‐uniform heat source/sink is discussed. The fluid is electrically conducting in the presence of a uniform applied magnetic field. The arising nonlinear problem is solved by the Keller box method. The effects of various physical parameters on skin friction, local Nusselt number, and Sherwood number are presented graphically and in tabular form. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21018
Mixed convection of a permeable fluid in a vertical channel with boundary conditions of a third kind
Authors: Umavathi J.C. , Veershetty Santosh
Published: July 2012

Numerical investigation of a steady mixed convective flow through a fluid‐saturated porous media in a vertical channel with boundary conditions of the third kind including the effects of viscous dissipation and Darcy dissipation has been studied. The plates exchange heat with an external fluid. Both conditions of equal and of different reference temperatures of the external fluid are considered. First, the simpler cases of either negligible Brinkman number or negligible Grashof number are addressed with the help of analytical solutions. The combined effects of buoyancy forces and viscous dissipation are analyzed by a perturbation series method valid for small values of perturbation parameter. To relax the conditions on the perturbation parameter, the governing equations are also evaluated numerically by a shooting technique that uses the classical explicit Runge–Kutta method of four slopes as an integration scheme and the Newton–Raphson method as a correction scheme. The problem is analyzed for different values of mixed convection parameters, porous parameter for equal and unequal Biot numbers, keeping the wall temperatures symmetric or asymmetric. The graphical results illustrating the effects of various parameters on the flow as well as average velocity and Nusselt numbers are presented. Further the analytical and numerical solutions agree very well for small values of the perturbation parameter. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21019
Mixed convective heat and mass transfer on a peristaltic flow of a non‐Newtonian fluid in a vertical asymmetric channel
Authors: Akram Safia , Ghafoor Abdul , Nadeem S.
Published: July 2012

In the present analysis we discuss the effects of mixed convective heat and mass transfer on the peristaltic flow of a non‐Newtonian fluid in a vertical asymmetric channel. The flow is investigated in a wave frame of reference moving with the velocitycaway from the fixed frame. The governing equations for the present flow problem are first modeled and then discussed. The analytical solution of the present flow problem is discussed using regular perturbation technique. The graphical results are discussed to see the effects of various physical parameters of interest. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21020
Neurocognitive and mood effects of alcohol in a naturalistic setting
Authors: Scholey AB , Benson S , Neale C , Owen L , Tiplady B
Published: July 2012

Objective

The current pilot study aimed to assess the effects of drinking alcohol in a naturalistic setting on aspects of performance.

Methods

Thirty individuals were approached and tested individually in a university campus bar. They provided details regarding alcoholic drinks consumption. Each was breathalysed before and after completion of a computerised test battery administered on a handheld device. The battery consisted of visual analogue mood scales, a series of alcohol‐sensitive psychomotor and cognitive tests.

Results

There were highly significant correlations between measured blood alcohol concentrations, estimated units of alcohol consumed and scores on a ‘sober‐drunk’ VAS (p < 0.001 in all cases). For performance, there was a characteristic alcohol‐associated shift in the speed/accuracy trade‐off (SATO), which was reflected as significantly more errors with less effect on speed across several measures (including maze performance and Serial Sevens). Individuals who were more intoxicated were also significantly less alert.

Conclusions

The data suggest that controlled laboratory tests into the effects of alcohol intoxication may have ecological validity, with SATO shifts amongst the characteristic impairments seen in both controlled and naturalistic settings. Copyright © 2012 John Wiley & Sons, Ltd.
Photodynamic Therapy–Induced Angiogenic Signaling: Consequences and Solutions to Improve Therapeutic Response
Authors: Gallagher‐Colombo Shannon M. , Maas Amanda L. , Yuan Min , Busch Theresa M.
Published: July 2012

Photodynamic therapy (PDT) can be a highly effective treatment for diseases ranging from actinic keratosis to cancer. While use of this therapy shows great promise in preclinical and clinical studies, understanding the molecular consequences of PDT is critical to designing better treatment protocols. A number of publications have documented alteration in angiogenic factors and growth factor receptors following PDT, which could abrogate treatment effect by inducing angiogenesis and reestablishment of the tumor vasculature. In response to these findings, work over the past decade has examined the efficacy of combining PDT with molecular targeting drugs, such as anti‐angiogenic compounds, in an effort to combat these PDT‐induced molecular changes. These combinatorial approaches increase rates of apoptosis, impair pro‐tumorigenic signaling, and enhance tumor response. This report will examine the current understanding of PDT‐induced angiogenic signaling and address molecular‐based approaches to abrogate this signaling or its consequences thereby enhancing PDT efficacy.
Electrical stimuli to increase cell proliferation on carbon nanotubes/mesoporous silica composites for drug delivery
Authors: Vila M. , Cicuéndez M. , Sánchez‐Marcos J. , Fal‐Miyar V. , Manzano M. , Prieto C. , Vallet‐Regi M.
Published: July 2012

The development of smart materials as bone implants is nowadays a challenging task to optimize their fast osteointegration. Nevertheless, no attempts have been done in joining the possibility of using electrical stimulation and drug delivery together in a material intended for bone tissue engineering. Moreover, the use of this synergy to induce bone healing is still limited until novel drug reservoirs material formulations allow an efficient applicability of the electrical stimuli. Herein, we present the biological response of osteoblasts cells, cultured over carbon nanotubes–mesoporous silica composites while exposed to external electrical stimulus. Moreover, its ability to function as drug delivery systems is also demonstrated. Bone cell metabolism was stimulated and mitochondrial activity was increased up to seven times in the presence of these composites under electrical stimulus, suggesting their potential application in bone regeneration processes. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A:213–221, 2013.
Evaluation of nanoarchitectured collagen type II molecules on cartilage engineering
Authors: Kuo Shyh Ming , Chiang Ming Yu , Lan Cheng Wen , Niu Gregory Cheng‐Chie , Chang Shwu Jen
Published: July 2012

Scaffold architecture, including the geometry and dimension of scaffolds, is an important parameter in cell adhesion, migration, proliferation, and differentiation. Following the characterization of collagen type II nanoarchitectured molecules, collagen fibrils (CNFs) and collagen spheres (CNPs) prepared using a high‐voltage electric field in our laboratory, we proposed to use these nanoarchitectured molecules to assess their influence on the culturing of chondrocytes in stirred bioreactors. The results demonstrate that chondrocytes rapidly formed more and larger chondrocyte pellets (spheroids) after the addition of nanoarchitectured molecules into the culture medium. The maintenance of chondrocytes with round morphology and increased glycosaminoglycan secretion indicated that these spheroids contained viable and un‐dedifferentiated chondrocytes. No significant increases in DNA content were detected. These results show that the introduction of these molecules did not affect chondrocyte proliferation during a 3‐day culture period. After the addition of CNPs and CNFs into the culture medium, the expression levels of collagen type II and aggrecan genes in chondrocytes increased significantly as demonstrated by real‐time PCR analysis. Interestingly, chondrocytes exhibited distinct collagen type II and aggrecan gene expression profiles in culture with CNPs and CNFs. The aggrecan gene expression level of the chondrocytes was 2.5‐fold greater following CFN addition than following the addition of CNPs. In contrast, the collagen type II expression level of the chondrocytes was 2.2‐fold greater following the addition of CNPs than following the addition of CNFs. The chondrocyte pellets rapidly restored defects in articular cartilage during a 1‐month implantation period in a rabbit model. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Bone healing response to a synthetic calcium sulfate/β‐tricalcium phosphate graft material in a sheep vertebral body defect model
Authors: Yang H. L. , Zhu X. S. , Chen L. , Chen C. M. , Mangham D. C. , Coulton L. A. , Aiken S. S.
Published: July 2012

The introduction of a material able to promote osteogenesis and remodelling activity in a clinically relevant time frame in vertebroplasty and kyphoplasty procedures may have patient benefit. We report thein‐vivoperformance of a biphasic synthetic bone graft material (Genex Paste, Biocomposites, UK) [test material], composed of calcium sulfate and β‐tricalcium phosphate, implanted into a sheep vertebral defect model. Cavities drilled into 4 adjacent vertebrae (L2 to L5) of 24 skeletally mature sheep were; (1) filled with the test material; (2) filled with commercially available polymethylmethacrylate [PMMA] cement; (3) remained empty [sham]. Analysis was performed immediately after implantation and at 8, 16, and 36 weeks post implantation. Sites were evaluated for bone growth with microCT analysis, histological examination, and mechanical testing under compression. The test material exhibited an improved tissue response over the PMMA, indicating a superior biological tolerance. MicroCT and histology indicated marked osteoregenerative capacity of the test material when compared with sham and the PMMA. The percentage of new bone formation was higher for the test material than sham at 16 and 36 weeks post implantation, with bone regeneration almost complete at 36 weeks in this group. Resorption of test material and the integration into new bone tissue were demonstrated. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Surface chemical and physical modification in stent technology for the treatment of coronary artery disease
Authors: Nazneen Feroze , Herzog Grégoire , Arrigan Damien W.M. , Caplice Noel , Benvenuto Pasquale , Galvin Paul , Thompson Michael
Published: July 2012

Coronary artery disease (CAD) kills millions of people every year. It results from a narrowing of the arteries (stenosis) supplying blood to the heart. This review discusses the merits and limitations of balloon angioplasty and stent implantation, the most common treatment options for CAD, and the pathophysiology associated with these treatments. The focus of the review is heavily placed on research efforts geared toward the modification of stent surfaces for the improvement of stent‐vascular compatibility and the reduction in the occurrence of related pathophysiologies. Such modifications may be chemical or physical, both of which are surveyed here. Chemical modifications may be passive or active, while physical modification of stent surfaces can also provide suitable substrates to manipulate the responses of vascular cells (endothelial, smooth muscle, and fibroblast). The influence of micro‐ and nanostructured surfaces on the in vitro cell response is discussed. Finally, future perspectives on the combination of chemical and physical modifications of stent surfaces are also presented. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Spinal duraplasty with two novel substitutes restored locomotor function after acute laceration spinal cord injury in rats
Authors: Liang Hongsheng , Li Changyu , Gao Aili , Liang Peng , Shao Yongxiang , Lin Tie , Zhang Xiangtong
Published: July 2012

A dural tear is a common complication after acute laceration spinal cord injury (ALSCI). An unrepaired dural tear is associated with poor locomotor functional recovery. Spinal duraplasty with biomaterials may promote functional recovery in ALSCI. However, an ideal dural substitute has not yet been found. In this work, we investigated the possibility of using a denuded human amniotic membrane (DHAM) or DHAM seeded on bone marrow stromal cells (DHAM–BMSCs) as duraplasty biomaterials. We patched broken dura with the two novel substitutes in an ALSCI rat model. At the end of the eighth week, we observed that the neural motor function was recovered according to the Basso–Beattie–Bresnahan scale, and the neural loop was successfully reestablished between the ends of the lesions by motor‐evoked potentials in the duraplasty groups. Moreover, the DHAM–BMSCs repaired the dura and resulted in a significant reduction in the total lesion and cystic volumes by nearly 10‐fold versus the control group (p< 0.01). The levels of neurotrophic factors and NF‐200‐positive fibers were also improved in the duraplasty groups, compared to the control group. Our data suggest that the two novel substitutes may be promising grafts for patching dural defects to improve locomotor function after ALSCI. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Evaluation of liver fibrosis by investigation of hepatic parenchymal perfusion using contrast‐enhanced ultrasound: An animal study
Authors: Ying Michael , Leung Gina , Lau Thomas Y.H. , Tipoe George L. , Lee Esther S.T. , Yuen Queeny W.H. , Huang Yan‐Ping , Zheng Yong‐Ping
Published: July 2012

Purpose:

To investigate the value of assessing the hepatic parenchymal perfusion in contrast‐enhanced ultrasound (CEUS) for evaluating liver fibrosis, using an animal model.

Methods:

Seventy Sprague–Dawley rats were divided into experimental (n = 35) and control (n = 35) groups. In the experimental group, liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride. CEUS of the liver was performed at a 2‐week interval for 14 weeks. Signal intensity of liver parenchyma was analyzed with time‐intensity curves. Histologic examination of liver specimens of the animals was performed to assess the fibrosis stage.

Results:

The peak signal intensity of hepatic parenchymal perfusion in stage 2–3 fibrosis was significantly lower than that in stage 0–1. The time to peak intensity of hepatic parenchymal perfusion was significantly longer in the experimental group than the control group, and in the stage 3 fibrosis than in stages 0–2 fibrosis. Using time to peak intensity of hepatic parenchymal perfusion to distinguish stage 3 fibrosis and stages 0–2 fibrosis, the optimum cutoff was 75,000 milliseconds with the sensitivity and specificity of 67% and 78%, respectively.

Conclusions:

This animal study showed that CEUS has the potential to be a complementary imaging tool in the evaluation of liver fibrosis. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound 40:462–470, 2012
Maximizing H‐Colorings of a Regular Graph
Authors: Galvin David
Published: July 2012

For graphs G and H, a homomorphism from G to H, or H‐coloring of G, is an adjacency preserving map from the vertex set of G to the vertex set of H. Our concern in this article is the maximum number of H‐colorings admitted by an n‐vertex, d‐regular graph, for each H. Specifically, writing for the number of H‐colorings admitted by G, we conjecture that for any simple finite graph H (perhaps with loops) and any simple finite n‐vertex, d‐regular, loopless graph G, we have

urn:x-wiley:03649024:jgt21658:equation:jgt21658-math-0002where is the complete bipartite graph with d vertices in each partition class, and is the complete graph on vertices.Results of Zhao confirm this conjecture for some choices of H for which the maximum is achieved by . Here, we exhibit for the first time infinitely many nontrivial triples for which the conjecture is true and for which the maximum is achieved by .We also give sharp estimates for and in terms of some structural parameters of H. This allows us to characterize those H for which is eventually (for all sufficiently large d) larger than and those for which it is eventually smaller, and to show that this dichotomy covers all nontrivial H. Our estimates also allow us to obtain asymptotic evidence for the conjecture in the following form. For fixed H, for all d‐regular G, we have

urn:x-wiley:03649024:jgt21658:equation:jgt21658-math-0013where as . More precise results are obtained in some special cases.
Plane Graphs with Maximum Degree Are Entirely ‐Colorable
Authors: Wang Yingqian , Mao Xianghua , Miao Zhengke
Published: July 2012

Let be a plane graph with the sets of vertices, edges, and faces V, E, and F, respectively. If one can color all elements in using k colors so that any two adjacent or incident elements receive distinct colors, then G is said to be entirely k‐colorable. Kronk and Mitchem [Discrete Math 5 (1973) 253‐260] conjectured that every plane graph with maximum degree Δ is entirely ‐colorable. This conjecture has now been settled in Wang and Zhu (J Combin Theory Ser B 101 (2011) 490–501), where the authors asked: is every simple plane graph entirely ‐colorable? In this article, we prove that every simple plane graph with is entirely ‐colorable, and conjecture that every simple plane graph, except the tetrahedron, is entirely ‐colorable.
On the Roots of Expected Independence Polynomials
Authors: Brown Jason I. , Dilcher Karl , Manna Dante V.
Published: July 2012

The independence polynomial of a (finite) graph is the generating function for the number of independent sets of each cardinality. Assuming that each possible edge of a complete graph of order n is independently operational with probability p, we consider the expected independence polynomial. We show here that for all fixed , the expected independence polynomials of complete graphs have all real, simple roots.
Altered balance between excitatory and inhibitory inputs onto CA1 pyramidal neurons from SV2A‐deficient but not SV2B‐deficient mice
Authors: Venkatesan Kumar , Alix Philippe , Marquet Alice , Doupagne Melissa , Niespodziany Isabelle , Rogister Bernard , Seutin Vincent
Published: July 2012

Synaptic vesicle protein 2 (SV2) is a glycoprotein that exists in three isoforms, SV2A, SV2B, and SV2C. SV2A knockout (KO) mice and SV2A/SV2B double KO (DKO) mice, but not SV2B KO animals, start to experience severe seizures and weight loss 7 days after birth and die at about postnatal day (P)14–P23. Because excitatory and inhibitory inputs play a major role in controlling neuronal excitability in the hippocampus, we examined the effects of SV2A and/or SV2B deletions on glutamatergic and GABAA neurotransmission in hippocampal CA1 pyramidal neurons. Spontaneous and miniature excitatory and inhibitory postsynaptic currents (sEPSCs, mEPSCs, sIPSCs, and mIPSCs, respectively) were recorded using the whole‐cell patch‐clamp technique in slices from P6–P14 mice. The frequency of sEPSCs was increased in SV2A KO and SV2A/SV2B DKO mice, but their amplitude was unchanged. Such changes were not observed in SV2B KOs. On the contrary, the frequency and amplitude of sIPSCs were decreased in SV2A KO and SV2A/SV2B DKO mice but not in SV2B KO animals, as reported previously for the CA3 region. Kinetic parameters of sIPSCs and sEPSCs were unchanged. Importantly, no changes were observed in any genotype when examining mEPSCs and mIPSCs. We conclude that action potential‐ and Ca2+‐dependent glutamatergic and GABAergic synaptic transmission are differentially altered in the hippocampus of SV2A‐deficient mice, whereas the mechanism of exocytosis itself is not changed. The altered balance between these major excitatory and inhibitory inputs is probably a contributing factor to seizures in SV2A KO and SV2A/SV2B DKO mice. © 2012 Wiley Periodicals, Inc.
Selective and non‐selective cyclooxygenase inhibitors delay stress fracture healing in the rat ulna
Authors: Kidd Lisa J. , Cowling Nick R. , Wu Andy C. , Kelly Wendy L. , Forwood Mark R.
Published: July 2012

Anti‐inflammatory drugs are widely used to manage pain associated with stress fractures (SFxs), but little is known about their effects on healing of those injuries. We hypothesized that selective and non‐selective anti‐inflammatory treatments would retard the healing of SFx in the rat ulna. SFxs were created by cyclic loading of the ulna in Wistar rats. Ulnae were harvested 2, 4 or 6 weeks following loading. Rats were treated with non‐selective NSAID, ibuprofen (30 mg/kg/day); selective COX‐2 inhibition, [5,5‐dimethyl‐3‐3 (3 fluorophenyl)‐4‐(4 methylsulfonal) phenyl‐2 (5H)‐furanone] (DFU) (2.0 mg/kg/day); or the novel c5a anatagonist PMX53 (10 mg/kg/day, 4 and 6 weeks only); with appropriate vehicle as control. Quantitative histomorphometric measurements of SFx healing were undertaken. Treatment with the selective COX‐2 inhibitor, DFU, reduced the area of resorption along the fracture line at 2 weeks, without affecting bone formation at later stages. Treatment with the non‐selective, NSAID, ibuprofen decreased both bone resorption and bone formation so that there was significantly reduced length and area of remodeling and lamellar bone formation within the remodeling unit at 6 weeks after fracture. The C5a receptor antagonist PMX53 had no effect on SFx healing at 4 or 6 weeks after loading, suggesting that PMX53 would not delay SFx healing. Both selective COX‐2 inhibitors and non‐selective NSAIDs have the potential to compromise SFx healing, and should be used with caution when SFx is diagnosed or suspected. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 235–242, 2013
Survival and reproduction of adult snowy owls tracked by satellite
Authors: Therrien Jean‐François , Gauthier Gilles , Bêty Joël
Published: July 2012

Satellite telemetry can provide valuable information on spatial ecology of animals, especially in species inhabiting remote areas such as the Arctic. However, caution is always needed when selecting transmitter size and attachment methods because of the potential negative impact of the device itself on individuals. We determined survival and reproductive performance of adult female snowy owls (Bubo scandiacus) tracked by satellite to evaluate potential adverse effects of transmitters. In summer 2007, we captured 12 adult females on their nest in the Canadian Arctic, marked them with 30‐g harness‐mounted transmitters, and tracked their movement for up to 3 years. All marked birds resumed normal activities shortly (<60 min) after release and none deserted their nest. We had 2 known deaths and 2 transmitters that stopped moving over 3 years, yielding an annual survival rate between 85.2 ± 7.0% and 92.3 ± 5.7%. Moreover, summer movement patterns, combined with ground checks in several cases, suggested that all successfully tracked birds initiated a nest every year after marking. Finally, laying date and clutch size of individuals did not differ before and after marking. Overall, our data indicate that life history traits of adult female snowy owls were not affected by satellite transmitters. © 2012 The Wildlife Society.
Temporary vocal fold immobility after chemocauterization of the pyriform sinus fistula opening with trichloroacetic acid
Authors: Park Joo Hyun , Jung Young Ho , Sung Myung‐Whun , Kim Kwang Hyun
Published: July 2012

Pyriform sinus fistula (PSF) is a rare branchial pouch anomaly. Circumferential chemocauterization of the opening with trichloroacetic acid (TCA) is a simple, reliable treatment of choice with little morbidity. However, we experienced two cases of vocal fold immobility after chemocauterization of the PSF opening with TCA. Vocal fold mobility recovered spontaneously within 8 weeks in both cases. Herein, we report these cases in addition to a review of the literature.
Juvenile recurrent respiratory papilloma: Variable intersurgical intervals
Authors: Ongkasuwan Julina , Friedman Ellen M.
Published: July 2012

Objectives/Hypothesis:

To analyze the patterns of surgical frequency in pediatric patients undergoing surgery with CO2 laser ablation for juvenile onset recurrent respiratory papillomatosis (JORRP). The hypothesis is that over time there is a high variability in surgical frequency independent of the use of an adjuvant therapy.

Study Design:

Retrospective case review.

Methods:

All pediatric patients treated surgically with the CO2 laser for JORRP by two senior surgeons at a tertiary pediatric hospital over an 11‐year period were evaluated. Regression analysis was performed. An online survey was conducted of the American Academy of Pediatric Otolaryngology membership on their practice patterns regarding JORRP.

Results:

Twenty‐nine patients were identified, and of those, 20 were included in regression analysis. Several distinct patterns were noted. Only five of the 20 patients (25%) had a constant rate of procedures throughout the observation period. Three (15%) of the patients had continual decrease and one (5%) of the patients had a continual increase in the surgical rate throughout the study period. Eleven (55%) had a fluctuation in the pattern of their recurrences. When queried on how they approach when to repeat intervention for JORRP patients, more than 16 responses were given, and the most common determinants included standard set interval, previous operative findings, and previous interval.

Conclusions:

The natural fluctuation in intersurgical intervals without the use of any adjuvant therapy confounds the use of intersurgical interval as an outcome measure for the success of adjuvant therapy. Accelerations and decelerations were noted but cannot be explained.
Renal dysfunction in liver transplant recipients: Evaluation of the critical issues
Authors: Weber Marc L. , Ibrahim Hassan N. , Lake John R.
Published: July 2012

Major progress has been made in the field of liver transplantation since the first procedure was performed nearly 50 years ago. Despite these improvements, renal dysfunction before and after liver transplantation remains a major complicating factor associated with increased health care costs, morbidity, and mortality. Creatinine-based estimates of renal function are inaccurate in the setting of end-stage liver disease and often lead to underdiagnosis and late intervention. This issue is critical in that it is important to understand both the etiology and chronicity of renal dysfunction before liver transplantation because the treatment clearly varies, especially with respect to simultaneous liver-kidney (SLK) transplantation. Because of the scarcity of available grafts, identifying appropriate candidates for SLK transplantation is crucial. Hepatorenal syndrome is common in liver transplant candidates; however, other etiologies of renal dysfunction need to be considered. Renal dysfunction after liver transplantation is common and may have an acute or chronic presentation. Although calcineurin inhibitors (CNIs) have been associated with post–liver transplant nephrotoxicity, their role may be overestimated, and other contributing etiologies should remain in a clinician's differential diagnosis. Alternatives to CNIs have been evaluated; however, a safe immunosuppressive regimen that achieves the preservation of renal function in liver transplant recipients remains to be established. In this review of the literature, renal dysfunction in the setting of liver transplantation is evaluated, and the critical issues that are barriers to improved outcomes are highlighted. Liver Transpl, 2012. © 2012 AASLD.
Mechanical and Biological Performances of New Scaffolds Made of Collagen Hydrogels and Fibroin Microfibers for Vascular Tissue Engineering
Authors: de Moraes Mariana Agostini , Paternotte Estelle , Mantovani Diego , Beppu Marisa Masumi
Published: July 2012

A microstructured composite material made of collagen hydrogel (matrix) and silk fibroin microfibers (randomly oriented reinforcing fibers) is investigated in order to conjugate the mechanical resistance of fibroin with the suitable biological performance of collagen to design new scaffolds for vascular tissue engineering. Results show that fibroin microfibers and collagen fibrils have suitable interfacial adhesion, and the scaffold exhibits improved mechanical properties if compared with a pure collagen hydrogel. Furthermore, the overall biological performance is improved.

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Novel Biopolymer Matrices for Microencapsulation of Phages: Enhanced Protection Against Acidity and Protease Activity
Authors: Dini Cecilia , Islan Germán A. , de Urraza Patricio J. , Castro Guillermo R.
Published: July 2012

Phage therapy by oral administration requires enhanced resistance of phages to the harsh gastric conditions. The aim of this work is the microencapsulation of phages in natural biopolymeric matrices as a protective barrier against the gastric environment. Alginate and pectin are used as base polymers. Further emulsification with oleic acid or coating with a different biopolymer is also studied. Emulsified pectin shows the maximum encapsulation efficiency and the highest protection against acidity, leaving more than 103 active phages after 30 min exposure at pH = 1.6, and protects phage from pepsin activity (4.2 mg mL−1). Non‐encapsulated phages are fully inactivated at pH = 1.6 or with pepsin (0.5 mg mL−1) after 10 min.

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Fabrication of Nanofiber Scaffolds With Gradations in Fiber Organization and Their Potential Applications
Authors: Xie Jingwei , Ma Bing , Michael Praveesuda Lorwattanapongsa , Shuler Franklin D.
Published: July 2012

A new and simple method for fabrication of nanofiber scaffolds with gradations in fiber organization is reported. The nanofiber organization, achieved by deposition of random fibers on the uniaxially aligned nanofiber mat in a gradient manner, directed morphological changes of applied adipose‐derived stem cells. These morphological changes and resultant biochemical changes can help mimic the structural orientation of complex biomechanical structures like the collagen fiber structure at the tendon‐to‐bone insertion site. In addition, chemical gradients can be established through nanoencapsulation in this novel scaffold allowing for enhanced biomedical applications.

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