bluuebunny/crossref_metadata_2025 huggingface dataset:
Charge‐based characterization of nanometric cationic bifunctional maghemite/silica core/shell particles by capillary zone electrophoresis
Authors: d'Orlyé Fanny , Varenne Anne , Georgelin Thomas , Siaugue Jean‐Michel , Teste Bruno , Descroix Stéphanie , Gareil Pierre
Published: July 2009

In view of employing functionalized nanoparticles (NPs) in the context of an immunodiagnostic, aminated maghemite/silica core/shell particles were synthesized so as to be further coated with an antibody or an antigen via the amino groups at their surface. Different functionalization rates were obtained by coating these maghemite/silica core/shell particles with 3‐(aminopropyl)triethoxysilane and 2‐[methoxy(polyethyleneoxy)propyl]‐trimethoxysilane at different molar ratios. Adequate analytical performances with CE coupled with UV‐visible detection were obtained through semi‐permanent capillary coating with didodecyldimethyl‐ammonium bromide, thus preventing particle adsorption. First, the influence of experimental conditions such as electric field strength, injected particle amount as well as electrolyte ionic strength and pH, was evaluated. A charge‐dependent electrophoretic mobility was evidenced and the separation selectivity was tuned according to electrolyte ionic strength and pH. The best resolutions were obtained at pH 8.0, high ionic strength (ca. 100 mM), and low total particle volume fraction (ca. 0.055%), thus eliminating interference effects between different particle populations in mixtures. A protocol derived from Kaiser's original description was performed for quantitation of the primary amino groups attached onto the NP surface. Thereafter a correlation between particle electrophoretic mobility and the density of amino groups at their surface was established. Eventually, CE proved to be an easy, fast, and reliable method for the determination of NP effective surface charge density.
Current separation and detection methods in microdialysis the drive towards sensitivity and speed
Authors: Guihen Elizabeth , O'Connor William T.
Published: July 2009

This review outlines some of the analytical challenges associated with the analysis of microdialysis (MD) samples, in particular, the minute complex sample volumes that are often encountered. In MD sampling many different low‐molecular‐weight molecules can be collected, but the research findings are often limited by the sensitivity, specificity, and reliability of the analytical technique that is coupled to the dialysis probe. Therefore it is critical that a lot of consideration is given in selecting the most suitable analytical method including the most appropriate detector. This review aims to highlight the strengths and weaknesses of a range of commonly used analytical methods employed in MD. In Section 1, a brief overview of the MD technique is described, followed by a discussion on some of the advantages and drawbacks of this sampling technique. Sections 2 and 3 examine analytical and other technical considerations regarding analysis, with special emphasis on the factors that specifically influence analytical detection. Section 4 outlines the most commonly employed analytical techniques used in MD, including HPLC coupled with various detectors. Detail is given regarding the LOD and LOQ for many applications using each detector. As MS is of such high importance in MD, a special sub‐section has been devoted to it. The importance of CE is also highlighted, with specific applications described. In addition, analytical techniques that do not appear to have found routine use in MD are discussed. Section 5 is concerned with recent innovations in chemical separation techniques, in particular MCE and ultra‐performance liquid chromatography. Specific applications of the coupling of these techniques with MD are highlighted, along with technical challenges associated with miniaturization. In the Section 6, the future outlook of MD is discussed. Techniques other than electrophoretic‐ and chromatographic based separation methods are outside the scope of this review.
CE of dsDNA in low‐molecular‐weight polyethylene oxide solutions
Authors: Pereira Fiona , Hassard Stuart , Hassard John , deMello Andrew
Published: July 2009

To realise effective size separations of nucleic acid fragments using CE, gel‐based matrices are commonly employed. The separation of label‐free dsDNA ladders and plasmid fragments in an uncross‐linked semi‐dilute poly (ethylene) oxide solution using multi‐pixel UV detection at 254 nm is reported. Improvements in the sensitivity of UV detection of dsDNA using signal averaging over multiple pixels is demonstrated. Separations performed using a diode array detector also allow the progress of the separation to be monitored as a function of time. Several polymers were examined including methyl cellulose, linear polyacrylamide, hydroxy (propyl) methylcellulose and polyethylene oxide. Operations parameters investigated included UV transparency, self‐coating capacity and separation efficiency. The results show complete resolution of all fragments under a range of conditions, including short separation lengths.
DNA migration mechanism analyses for applications in capillary and microchip electrophoresis
Authors: Forster Ryan E. , Hert Daniel G. , Chiesl Thomas N. , Fredlake Christopher P. , Barron Annelise E.
Published: July 2009

In 2009, electrophoretically driven DNA separations in slab gels and capillaries have the sepia tones of an old‐fashioned technology in the eyes of many, even while they remain ubiquitously used, fill a unique niche, and arguably have yet to reach their full potential. For comic relief, what is old becomes new again: agarose slab gel separations are used to prepare DNA samples for “next‐gen” sequencing platforms (e.g. the Illumina and 454 machines) – dsDNA molecules within a certain size range are “cut out” of a gel and recovered for subsequent “massively parallel” pyrosequencing. In this review, we give a Barron lab perspective on how our comprehension of DNA migration mechanisms in electrophoresis has evolved, since the first reports of DNA separations by CE (∼1989) until now, 20 years later. Fused‐silica capillaries and borosilicate glass and plastic microchips quietly offer increasing capacities for fast (and even “ultra‐fast”), efficient DNA separations. While the channel‐by‐channel scaling of both old and new electrophoresis platforms provides key flexibility, it requires each unique DNA sample to be prepared in its own micro or nanovolume. This Achilles' heel of electrophoresis technologies left an opening through which pooled sample, next‐gen DNA sequencing technologies rushed. We shall see, over time, whether sharpening understanding of transitions in DNA migration modes in crosslinked gels, nanogel solutions, and uncrosslinked polymer solutions will allow electrophoretic DNA analysis technologies to flower again. Microchannel electrophoresis, after a quiet period of metamorphosis, may emerge sleeker and more powerful, to claim its own important niche applications.
Component correlations in structure‐specific seismic loss estimation
Authors: Bradley Brendon A. , Lee Dominic S.
Published: July 2009

This paper addresses correlations between multiple components in structure‐specific seismic loss estimation. To date, the consideration of such correlations has been limited by methodological tractability, increased computational demand, and a paucity of data for their computation. The effect of component correlations, which arises in various forms, is however a significant factor affecting the results of structure‐specific seismic loss estimation and therefore it is prudent that adequate consideration be given to their effect. This paper provides the details of a tractable and computationally efficient seismic loss estimation methodology in which correlations can be considered. Methods to determine the necessary correlations are discussed, particularly those that can be used in the absence of sufficient empirical data, for which values are suggested based on the judgement. The effects of various assumptions regarding correlations are illustrated via application to a case‐study office structure. It is observed that certain correlation assumptions can lead to errors in excess of 50% in the lognormal standard deviation in the loss given intensity and loss hazard relationships, while full consideration of partial correlations is 50 times more computationally expensive than other assumptions. Copyright © 2009 John Wiley & Sons, Ltd.
Proton radiation therapy for primary sphenoid sinus malignancies: Treatment outcome and prognostic factors
Authors: Truong Minh Tam , Kamat Urmila R. , Liebsch Norbert J. , Curry William T. , Lin Derrick T. , Barker Fred G. , Loeffler Jay S. , Chan Annie W.
Published: July 2009

Background

The purpose of this study was to determine treatment outcome and prognostic factors in patients with locally advanced primary sphenoid sinus malignancy treated with proton radiation therapy.

Methods

Between 1991 and 2005, 20 patients with primary sphenoid sinus malignancy received proton beam to a median dose of 76 Gray equivalent.

Results

With a median follow‐up of 27 months, the 2‐year local, regional, and freedom from distant metastasis rates were 86%, 86%, and 50%, respectively. The disease‐free and overall‐survival rates at 2 years were 31% and 53%, respectively. In multivariate analysis, oropharyngeal involvement (p = .005) and anterior cranial fossa invasion (p = .02) were predictive for poor disease‐free survival rate. Brain invasion was predictive for decreased overall‐survival rate (p = .05).

Conclusions

Proton radiation therapy results in excellent local control in patients with advanced primary sphenoid sinus malignancy. Brain invasion, involvement of the oropharynx and anterior cranial fossa are important prognostic factors. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Expression of membrane type 1 matrix metalloproteinase in medullary thyroid carcinoma: Prognostic implications
Authors: Cavalheiro Beatriz Godoi , Junqueira Consuelo Rodrigues , Brandão Lenine Garcia
Published: July 2009

Background.

Clinical and pathologic examinations cannot always provide a prognosis for patients with medullary thyroid carcinoma. Membrane type 1 matrix metalloproteinase (MT1‐MMP) can act directly on carcinogenesis and takes part in 1 of the processes of metalloproteinase 2 activation, an enzyme related to prognostic impairment of patients with such tumor.

Methods.

Thirty‐five patients who were submitted to surgery were followed up for an average of 74 months. Postoperative and final medical conditions were characterized for comparison with MT1‐MMP immunostainings, performed in surgical paraffin blocks. A value of p < .05 was considered statistically significant.

Results.

Proposed index (association of proportion and intensity of immunostaining) and proportion of immunostained cells in primary specimens were correlated with cure or persistence after initial operations (p = .0216 and p = .0098, respectively).

Conclusion.

MT1‐MMP immunostaining in primary tumor specimens is a new and complementary prognostic predictor in patients with medullary thyroid carcinomas. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Oral sensation and function: A comparison of patients with innervated radial forearm free flap reconstruction to healthy matched controls
Authors: Loewen Irene J. , Boliek Carol A. , Harris Jeffrey , Seikaly Hadi , Rieger Jana M.
Published: July 2009

Background.

Limited evidence exists for the use of innervated radial forearm free flap (RFFF) reconstruction of hemiglossectomy defects. This study reports on sensation, mastication, and speech outcomes for patients with innervated RFFF reconstruction of the anterior two‐thirds of the tongue.

Methods.

Sensation, mastication, and speech intelligibility were assessed in 8 patients and age‐ and sex‐matched controls.

Results.

Sensation of intact tongue tissue after reconstruction of the hemitongue did not differ from controls. Although some sensory ability was restored to patients' reconstructed tongue, differences existed between the patient group and controls. However, whole mouth sensations resulted in similar sensory ability as controls. Whereas patients demonstrated adequate masticatory and speech ability, differences existed between patients and controls.

Conclusion.

Although some sensory ability is preserved in patients who have had tongue reconstruction with an innervated RFFF, functional outcomes such as masticatory ability and speech intelligibility may be affected in some patients. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Design for usability on supply chain management systems implementation
Authors: Lin Chao‐Hsien , Hwang Sheue‐Ling , Wang Eric Min‐yang , Peng Shu‐Ling
Published: July 2009

Supply chain management (SCM) systems implementation has become a fashion due to advances in information technology and pressures of market competition. Unfortunately, successful implementation was rare. In this article, the concept of usability was extended in an explorative case study to crystallize design for usability (DFU) principles in a large‐scale SCM systems implementation project at a leading semiconductor manufacturing company in Taiwan. Proposed was a holistic usability framework to guide the analysis of DFU as well as the compilation of an evidence database composed of design documentation, post hoc evaluation, semistructured interviews, and participant observation. This research revealed a set of usability needs and coping strategies found throughout a series of systems design and redesign processes at the case company. As a result, an emergent usability framework in the form of ICOM (Input, Control, Output, and Mechanism) dimensions was proposed to guide the implementation of SCM systems. © 2009 Wiley Periodicals, Inc.
Modelling blowing snow redistribution to prairie wetlands
Authors: Fang X. , Pomeroy J. W.
Published: July 2009

Blowing snow transports and sublimates a substantial portion of the seasonal snowfall in the prairies of western Canada. Snow redistribution is an important feature of prairie hydrology as deep snowdrifts provide a source of meltwater to replenish ponds and generate streamflow in this dry region. The spatial distribution of snow water equivalent in the spring is therefore of great interest. A test of the distributed and aggregated modelling strategies for blowing snow transport and sublimation was conducted at the St. Denis National Wildlife Area in the rolling, internally drained prairie pothole region east of Saskatoon, Saskatchewan, Canada. A LiDAR‐based DEM and aerial photograph‐based vegetation cover map were available for this region. A coupled complex windflow and blowing snow model was run with 262,144 6 m × 6 m grid cells to produce spatially distributed estimates of seasonal blowing snow transport and sublimation. The calculation was then aggregated to seven landscape units that represented the major influences of surface roughness, topography and fetch on blowing snow transport and sublimation. Both the distributed and aggregated simulations predicted similar end‐of‐winter snow water equivalent with substantial redistribution of blowing snow from exposed sparsely vegetated sites across topographic drainage divides to the densely vegetated pothole wetlands. Both simulations also agreed well with snow survey observations. While the distributed calculations provide a fascinating and detailed visual image of the interaction of complex landscapes and blowing snow redistribution and sublimation, it is clear that blowing snow transport and sublimation calculations can be successfully aggregated to the spatial scale of the major landscape units in this environment. This means that meso and macroscale hydrological models can represent blowing snow redistribution successfully in the prairies. Copyright © 2009 John Wiley & Sons, Ltd.
Multiple human papillomavirus genotype infections in cervical cancer progression in the study to understand cervical cancer early endpoints and determinants
Authors: Wentzensen Nicolas , Schiffman Mark , Dunn Terence , Zuna Rosemary E. , Gold Michael A. , Allen Richard A. , Zhang Roy , Sherman Mark E. , Wacholder Sholom , Walker Joan , Wang Sophia S.
Published: July 2009

Determining the causal attribution of human papillomavirus (HPV) genotypes to cervical disease is important to estimate the effect of HPV vaccination and to establish a type spectrum for HPV‐based screening. We analyzed the prevalence of HPV infections and their attribution to cervical disease in a population of 1,670 women referred to colposcopy for abnormal cytology at the University of Oklahoma. HPV genotyping was performed from cytology specimens using the Linear Array assay that detects 37 HPV genotypes. We used different methods of type attribution to revised cervical disease categories. We found very high prevalence of multiple HPV infections with up to 14 genotypes detected in single specimens. In all disease categories except for cancers, there was a significant trend of having more infections at a younger age. We did not see type interactions in multiple genotype infections. HPV16 was the most frequent genotype at all disease categories. Based on different attribution strategies, the attribution of vaccine genotypes (6, 11, 16, 18) ranged from 50.5 to 67.3% in cancers (n = 107), from 25.6 to 74.8% in CIN3 (n = 305), from 15.2 to 52.2% in CIN2 (n = 427), and from 6.6 to 26.0% in <CIN2 (n = 708). In the HSIL cytology group (n = 651), attribution ranged from 26.1 to 64.7%. The attribution of vaccine types to HSIL was substantially higher compared to the lower cytology categories. The potential range of HPV genotype attribution is wide at the disease categories <CIN2 to CIN3. Genotyping from cervical lesions and analyzing viral oncogene expression can improve estimates of HPV genotype attribution. © 2009 UICC
Association of HLA‐DRB1, interleukin‐6 and cyclin D1 polymorphisms with cervical cancer in the Swedish population—A candidate gene approach
Authors: Castro Felipe A. , Haimila Katri , Sareneva Inna , Schmitt Markus , Lorenzo Justo , Kunkel Nelli , Kumar Rajiv , Försti Asta , Kjellberg Lennart , Hallmans Göran , Lehtinen Matti , Hemminki Kari , Pawlita Michael
Published: July 2009

High‐risk human papillomavirus (hrHPV) infection is the major risk factor for cervical cancer (CxCa). The role of genetic susceptibility in the disease has been suggested, but the existing data lack consistency. We conducted a nested case‐control study on 973 CxCa cases and 1,763 matched controls, from two Swedish population‐based cohorts to examine the association of common genetic variants with CxCa risk. Human leukocyte antigen (HLA) alleles and 24 other polymorphisms in 14 genes were selected on the basis of reported association or mechanistic plausibility with an HPV infection or cervical cancer development. Genotyping was conducted using multiplex PCR and Luminex technology. A significant association of CxCa with various polymorphisms was observed: rs1800797 in the IL‐6 gene (odds ratio [OR] = 0.88, 95% confidence intervals [CI]: 0.79–0.99); rs1041981 in the LTA gene (OR = 0.87, 95% CI: 0.78–0.98), and rs9344 in the CCND1 gene (OR = 1.14, 95% CI: 1.02–1.27), for those individuals carrying the rare allele. Additionally, the alleles 0401 and 1501 of the HLA class II DRB1 locus were associated with an increased risk (OR = 1.23, 95% CI: 1.04–1.45 and OR = 1.29, 95% CI: 1.11–1.50, respectively), and allele 1301 was associated with decreased risk (OR = 0.59, 95% CI: 0.47–0.73). The effects of CCND1 and the HLA*DRB1 alleles were independent of the effect of smoking. We did not find any association of risk with polymorphisms in genes related to the innate immune system. In conclusion, our study provides evidence for genetic susceptibility to CxCa due to variations in genes involved in the immune system and in cell cycle. © 2009 UICC
Biological effects induced by insulin‐like growth factor binding protein 3 (IGFBP‐3) in malignant melanoma
Authors: Øy Geir Frode , Slipicevic Ana , Davidson Ben , Solberg Faye Ragnar , M. Mælandsmo Gunhild , Flørenes Vivi Ann
Published: July 2009

The insulin like growth factor (IGF) signaling pathway has been shown to contribute to melanoma progression, but little is known about the role of the IGF binding protein 3 (IGFBP‐3) in melanoma biology. The aim of the present study was to characterize expression, function and regulation of IGFBP‐3 in malignant melanomas and study its potential as a biomarker. The expression of IGFBP‐3 varied between different human melanoma cell lines and reintroduction of the protein in non‐expressing cells led to induction of apoptosis. Interestingly, in cell lines expressing endogenous IGFBP‐3, siRNA silencing of the protein led to a cell line‐dependent decrease in proliferation, but had no effect on apoptosis and invasion. Examination of patient material showed that IGFBP‐3 is unexpressed in benign nevi while a slight increase in protein expression was seen in primary and metastatic melanoma. However, expression of the protein was low and no correlation was found with circulating levels of IGFBP‐3 in serum, suggesting that IGFBP‐3 has limited potential as a predictive marker in malignant melanoma. We showed that promoter methylation of IGFBP‐3 occurred in both melanoma cell lines and patient material, implicating epigenetic silencing as a regulation mechanism. Furthermore, expression of the protein was shown to be regulated by the PI3‐kinase/AKT and MAPK/ERK1/2 pathways. In summary, our findings suggest that IGFBP‐3 can exert dual functional effects influencing both apoptosis and proliferation. Development of resistance to the antiproliferative effects of IGFBP‐3 may be an important step in progression of malignant melanomas.
Fluorescence lifetime imaging microscopy of chemotherapy‐induced apoptosis resistance in a syngenic mouse tumor model
Authors: Keese M. , Yagublu V. , Schwenke K. , Post S. , Bastiaens P.
Published: July 2009

During cancer therapy with DNA‐damaging drug‐agents, the development of secondary resistance to apoptosis can be observed. In the search for novel therapeutic approaches that can be used in these cases, we monitored chemotherapy‐induced apoptosis resistance in a syngenic mouse tumor model. For this, syngenic murine colorectal carcinoma cells, which stably expressed a FRET‐based caspase‐3 activity sensor, were introduced into animals to induce peritoneal carcinomatosis or disseminated hepatic metastases. This syngenic system allowed in vitro, in vivo and ex vivo analysis of chemotherapy induced apoptosis induction by optically monitoring the caspase‐3 sensor state in the tumor cells. Tumor tissue analysis of 5‐FU treated mice showed the selection of 5‐FU‐induced apoptosis resistant tumor cells. These and chemo‐naive fluorescent tumor cells could be re‐isolated from treated and untreated mice and propagated in cell culture. Re‐exposure to 5‐FU and second line treatment modalities in this ex‐vivo setting showed that 5‐FU induced apoptosis resistance could be alleviated by imatinib mesylate (Gleevec). We thus show that syngenic mouse systems that stably express a FRET‐based caspase‐3 sensor can be employed to analyse the therapeutic efficiency of apoptosis inducing chemotherapy.
Probabilistic fuzzy systems in value‐at‐risk estimation
Authors: Almeida R. J. , Kaymak U.
Published: July 2009

Value‐at‐risk (VaR) is a popular measure for quantifying the market risk that a financial institution faces into a single number. Owing to the complexity of financial markets, the risks associated with a portfolio varies over time. Consequently, advanced methods of VaR estimation use parametric conditional models of portfolio volatility (e.g. generalized autoregressive heteroscedasticity (GARCH) models) to adapt risk estimation to changing market conditions. However, more flexible semi‐parametric methods that adapt to the highly flexible underlying data distribution are better suited for accurate VaR estimation. In this paper, we consider VaR estimation by using probabilistic fuzzy systems (PFSs). A PFS is a semi‐parametric method that combines a linguistic description of the system behaviour with statistical properties of the data. Therefore, they provide the potential to adapt estimations of probability density to the linguistic framework of the modeller. We study two approaches to designing probabilistic fuzzy VaR models and compare their performances with the performance of a GARCH model. It is found that statistical back testing always accepts PFS models after tuning, whereas GARCH models may be rejected. Copyright © 2009 John Wiley & Sons, Ltd.
Evolving fuzzy modelling in risk analysis
Authors: Ballini R. , Mendonça A. R. R. , Gomide F.
Published: July 2009

Traditionally, forecast methodologies emphasize precise point‐forecasts of stationary data. Risk analysis demands forecasts that, in practice, must be developed using imprecise and nonstationary data. Currently, value‐at‐risk (VaR) is widely employed in risk analysis. VaR requires a form of interval forecasts. Generalized autoregressive conditional heteroskedasticity (GARCH) models are stochastic recursive systems commonly adopted in financial prediction. This paper addresses a new approach to handle imprecise and nonstationary data using evolving fuzzy modelling translated into a recursive, adaptive forecasting procedure. VaR analysis is conducted to compare the performance and robustness of evolving fuzzy forecasting against GARCH using São Paulo Stock Exchange data. Copyright © 2009 John Wiley & Sons, Ltd.
Poly‐ϵ‐caprolactone/gel hybrid scaffolds for cartilage tissue engineering
Authors: Schagemann J. C. , Chung H. W. , Mrosek E.H. , Stone J.J. , Fitzsimmons J.S. , O'Driscoll S. W. , Reinholz G. G.
Published: July 2009

The aim of this study was to determine the suitability of hybrid scaffolds composed of naturally derived biopolymer gels and macroporous poly‐ϵ‐caprolactone (PCL) scaffolds for neocartilage formation in vitro. Rabbit articular chondrocytes were seeded into PCL/HA (1 wt % hyaluronan), PCL/CS (0.5 wt % chitosan), PCL/F (1:3 fibrin sealant plus aprotinin), and PCL/COL1 (0.24% type I collagen) hybrids and cultured statically for up to 50 days. Growth characteristics were evaluated by histological analysis, scanning electron microscopy, and confocal laser scanning microscopy. Neocartilage was quantified using a dimethyl‐methylene blue assay for sulfated glycosaminoglycans (sGAG) and an enzyme‐linked immunosorbent assay for type II collagen (COL2), normalized to dsDNA content by fluorescent PicoGreen assay. Chondrocytes were homogenously distributed throughout the entire scaffold and exhibited a predominantly spheroidal shape 1 h after being seeded into scaffolds. Immunofluorescence depicted expanding proteoglycan deposition with time. The sGAG per dsDNA increased in all hybrids between days 25 and 50. PCL/HA scaffolds consistently promoted highest yields. In contrast, total sGAG and total COL2 decreased in all hybrids except PCL/CS, which favored increasing values and a significantly higher total COL2 at day 50. Overall, dsDNA content decreased significantly with time, and particularly between days 3 and 6. The PCL/HA hybrid displayed two proliferation peaks at days 3 and 25, and PCL/COL1 displayed one proliferation peak at day 12. The developed hybrids provided distinct short‐term environments for implanted chondrocytes, with not all of them being explicitly beneficial (PCL/F, PCL/COL1). The PCL/HA and PCL/CS hybrids, however, promoted specific neocartilage formation and initial cell retention and are thus promising for cartilage tissue engineering. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res 2010
Antibacterial effects and dissolution behavior of six bioactive glasses
Authors: Zhang Di , Leppäranta Outi , Munukka Eveliina , Ylänen Heimo , Viljanen Matti K. , Eerola Erkki , Hupa Mikko , Hupa Leena
Published: July 2009

Dissolution behavior of six bioactive glasses was correlated with the antibacterial effects of the same glasses against sixteen clinically important bacterial species. Powdered glasses (<45 μm) were immersed in simulated body fluid (SBF) for 48 h. The pH in the solution inside the glass powder was measured in situ with a microelectrode. After 2, 4, 27, and 48 h, the pH and concentration of ions after removing the particles and mixing the SBF were measured with a normal glass pH electrode and ICP‐OES. The bacteria were cultured in broth with the glass powder for up to 4 days, after which the viability of the bacteria was determined. The antibacterial effect of the glasses increased with increasing pH and concentration of alkali ions and thus with increased dissolution tendency of the glasses, but it also depended on the bacterium type. The changes in the concentrations of Si, Ca, Mg, P, and B ions in SBF did not show statistically significant influence on the antibacterial property. Bioactive glasses showed strong antibacterial effects for a wide selection of aerobic bacteria at a high sample concentration (100 mg/mL). The antibacterial effects increased with glass concentration and a concentration of 50 mg/mL (SA/V 185 cm−1) was required to generate the bactericidal effects. Understanding the dissolution mechanisms of bioactive glasses is essential when assessing their antibacterial effects. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res 2010
Facilitating tissue infiltration and angiogenesis in a tubular collagen scaffold
Authors: Gérard Catherine , Doillon Charles J.
Published: July 2009

Among different strategies to provide blood supply to tissue‐engineered devices and implants, the use of arteriovenous loops and bundles has been proposed. The aim of this study was to compare the vascularization and healing processes that took place in a one‐end closed tubular collagen‐based scaffold at different implantation sites in mice. These conditions were in the presence or absence of heparin and/or bone marrow cells. By 30 days, very few cell infiltrations were observed in the dorsal subcutaneous and peritoneal implants at any conditions; however, the presence of heparin and bone marrow cells improved cell infiltration toward an inflammatory reaction. The insertion of an arteriovenous bundle into the central cavity of the scaffold resulted in partial wound tissue infiltration in the control scaffolds implanted subcutaneously in the hind limb. In similar conditions, the presence of bone marrow cells and heparin resulted in dense wound tissue with numerous capillaries and a significant amount of newly deposited collagen fibers. The design of a central cavity in a porous scaffold with one closed end may facilitate invasion from the central part of the implant toward the implant wall. In addition, the presence of both a vascular component and stem/progenitor cells may lead to a vascularized implant while limiting the inflammatory reaction. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Adsorption and release of BMP‐2 on nanocrystalline apatite‐coated and uncoated hydroxyapatite/β‐tricalcium phosphate porous ceramics
Authors: Autefage Hélène , Briand‐Mésange Fabienne , Cazalbou Sophie , Drouet Christophe , Fourmy Daniel , Gonçalvès Stéphane , Salles Jean‐Pierre , Combes Christèle , Swider Pascal , Rey Christian
Published: July 2009

The association of bone morphogenetic proteins (BMPs) with calcium phosphate bioceramics is known to confer them osteoinductive properties. The aim of this study was to evaluate the surface properties, especially regarding recombinant human BMP‐2 (rhBMP‐2) adsorption and release, of commercial sintered biphasic calcium phosphate ceramics after coating with biomimetic nanocrystalline apatite. The raw and coated ceramics exhibited similar macroporous structures but different nanometer‐sized pores contents. Both types of ceramics showed Langmuir‐type adsorption isotherms of rhBMP‐2. The coating noticeably increased the rate of adsorption and the total amount of growth factor taken up, but the maximum coverage per surface area unit as well as the affinity constant appeared lower for coated ceramics compared with raw ceramic surfaces. The limited advantage gained by coating the ceramics can be assigned to a lower accessibility of the surface adsorption sites compared with the raw ceramics. The quantity of rhBMP‐2 spontaneously released in cell culture medium during the first weeks was lower for coated samples than for uncoated ceramics and represented a minor fraction of the total adsorbed amount. In conclusion, the nanocrystalline apatite coating was found to favor the adsorption of rhBMP‐2 while providing a mean to fine tune the release of the growth factor. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Development of an in vitro model on cellular adhesion on granular natural bone mineral under dynamic seeding conditions—A pilot study
Authors: Rameis Marie‐Therese , Cei Silvia , Bernardi Johannes , Watzek Georg , Gruber Reinhard
Published: July 2009

Adhesion of osteogenic cells on biomaterials can be studied with static in vitro models, whereas models representing dynamic seeding conditions are rare. Herein, we present an in vitro model to study cell adhesion on granular biomaterials under dynamic seeding conditions. Radiolabeled osteogenic MC3T3‐E1 cells were allowed to adhere to granules of natural bovine bone mineral (NBM) under constant rotation. Adhesion of MC3T3‐E1 cells was determined by liquid scintillation counting, and cell morphology was visualized by scanning electron microscopy. Cell viability was determined by MTT assay under static and dynamic conditions, at room and body temperature, and in the presence or absence of serum. We show here that MC3T3‐E1 cells rapidly adhere to NBM, reaching a peak 3 h after seeding. Attached cells display characteristic signs of spreading. Five to ten percent of total radioactivity remained on NBM after the removal of nonadherent cells. Viability is maintained at room temperature and under rotation for upto 3 h. This data suggests that the dynamic in vitro model presented here provides a tool to study cell adhesion on granular biomaterials. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Histomorphologic analysis of 30 plateau root form implants retrieved after 8 to 13 years in function. A human retrieval study
Authors: Coelho Paulo G. , Marin Charles , Granato Rodrigo , Suzuki Marcelo
Published: July 2009

The objective of this study was to evaluate the morphology and integration status of 30 human retrieved plateau root form implants. Thirty plateau design root form implants that were in function from 8 to 13 years were retrieved from patients due to prosthetic reasons. Following surgical removal, the samples remained in 10% buffered formaline for 7 days. Bone morphology was evaluated by transmitted and polarized light microscopy, and bone‐to‐implant contact (BIC) histomorphometric assessment was determined through computer software. Irrespective of time in vivo, lamellar bone was observed in close contact with the implant surface and between plateaus. BIC ranged from ∼20 to ∼80%. Polarized light microscopy showed a highly directional osteonic morphology between plateaus for most implants. A haversian‐like microstructure running perpendicular to and along with the implants' long axis (between plateaus) was observed in regions of cortical and trabecular bone, revealing a unique bone microstructural evolution over time around functionally loaded plateau root form implants. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Effects of protein A immunoadsorption in patients with advanced chronic dilated cardiomyopathy
Authors: Doesch Andreas O. , Konstandin Mathias , Celik Sultan , Kristen Arnt , Frankenstein Lutz , Hardt Stefan , Goeser Stefan , Kaya Ziya , Katus Hugo A. , Dengler Thomas J.
Published: July 2009

Objectives:

The objective of this study was to investigate functional effects of immunoadsorption (IA) in severely limited study patients with chronic nonfamilial dilated cardiomyopathy (DCM), and to analyze the prevalence of Troponin I (TNI) autoantibodies.

Background:

Immunoadsorption (IA) has been shown to induce early hemodynamic improvement in patients with nonfamilial DCM.

Methods:

We performed IA using Immunosorba columns on five consecutive days in 27 patients with chronic DCM, congestive heart failure of NYHA class ≥II, left ventricular ejection fraction below 40%, and mean time since initial diagnosis of 7.2 ± 6.8 years.

Results:

Immediately after IA, IgG decreased by 87.7% and IgG3 by 58.5%. Median NT‐pro BNP was reduced from 1740.0 ng/L at baseline to 1504.0 ng/L after 6 months (P = 0.004). Mean left ventricular ejection fraction (LVEF) was not significantly improved overall (24.1 ± 7.8% to 25.4 ± 10.4% after 6 months, P = 0.38), but LVEF improved ≥5% (absolute) in 9 of 27 (33%) patients. Bicycle spiroergometry showed a significant increase in exercise capacity from 73.7 ± 29.4 Watts to 88.8 ± 31.1 Watts (P = 0.003) after 6 months while VO2max rose from 13.7 ± 3.8 to 14.9 ± 3.0 mL/min kg after 6 months (P = 0.09). Subgroup analysis revealed a higher NT‐pro BNP reduction in patients with shorter disease duration (P = 0.03) and without TNI autoantibodies at baseline (P = 0.05). All 9 patients with an absolute increase of LVEF of ≥5.0% were diabetic (P = 0.0001).

Conclusions:

In this study, on severely limited heart failure patients with nonfamilial DCM, IA therapy moderately improved markers of heart failure severity in a limited subgroup of patients. This may be due to the selected study population with end‐stage heart failure patients and the lower reduction of IgG3 compared to previous studies. Future blinded multicenter studies are necessary to identify those patients that benefit most. J. Clin. Apheresis 2009. © 2009 Wiley‐Liss, Inc.
Decision support—Do you have it?
Authors: Hatch Toby , Stratton William , Lawson Raef A. , Desroches Denis
Published: July 2009

Many organizations want to be able to make better decisions using their cost and profitability system, yet are thwarted from doing so for a variety of reasons. This article shows how organizations can improve their current systems. It discusses some unachieved goals, and also demonstrates how you can successfully support business decisions using a cost and profitability system. © 2009 Wiley Periodicals, Inc.
Protein cytoskeleton and overexpression of Na+,K+‐ATPase in opossum kidney cells
Authors: Silva Elisabete , Soares‐da‐Silva Patrício
Published: July 2009

Previous studies have shown that over time in culture opossum kidney (OK) cells are endowed with increased Na+,K+‐ATPase activity and expression (Silva et al., , J Membr Biol 212:163–175; Silva and Soares‐da‐Silva, , Am J Physiol Regul Integr Comp Physiol 293:R1764–R1770). The present work evaluated the cytoskeleton reorganization in OK cells at passages 40 and 80 in culture and its possible relationship with membrane transport proteins and cell morphology. It is shown that OK cells with 80 passages in culture have increased size, internal complexity, and total protein expression. In OK cells with 80 passages in culture the use of in‐cell western showed that ezrin/radixin/moesin complex was increased by 20%. The most abundant ankyrin‐G isoform in OK cells with 40 passages was the ∼200/220 kDa isoform, whereas in OK cells with 80 passages the most abundant isoform was the ∼170 kDa isoform. The spectrin‐βII ∼240 kDa isoform, the predominant isoform in OK cells with 40 passages, was marginally detected in OK cells with 80 passages. Besides Na+,K+‐ATPase, GLUT2, and NHE3 expression was also significantly increased in OK cells with 80 passages. It is concluded that the prolonged cell passaging of OK cells results in an interesting and valuable experimental model to analyze the reorganization of the renal cell cytoskeleton proteins and its relationship with transporter and signaling membrane proteins. J. Cell. Physiol. 221: 318–324, 2009. © 2009 Wiley‐Liss, Inc.
New methods for chicken embryo manipulations
Authors: El‐Ghali Nissrine , Rabadi Maes , Ezin Akouavi M. , De Bellard Maria Elena
Published: July 2009

The capacity to image a growing embryo while simultaneously studying the developmental function of specific molecules provides invaluable information on embryogenesis. However, until recently, this approach was accomplished with difficulty both because of the advanced technology needed and because an easy method of minimizing damage to the embryo was unavailable. Here, we present a novel way of adapting the well‐known EC culture of whole chick embryos to time‐lapse imaging and to functional molecular studies using blocking agents. The novelty of our method stems from the ability to apply blocking agents ex ovo as well as in ovo. We were able to study the function of a set of molecules by culturing developing embryos ex ovo in tissue culture media containing these molecules or by injecting them underneath the live embryo in ovo. The in ovo preparation is particularly valuable, because it extends the period of time during which the developmental function of the molecule can be studied and it provides an easy, reproducible method for screening a batch of molecules. These new techniques will prove very helpful in visualizing and understanding the role of specific molecules during embryonic morphogenesis, including blood vessel formation. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Whole body regeneration in a colonial ascidian, Botrylloides violaceus
Authors: Brown Federico D. , Keeling Elena L. , Le Anna D. , Swalla Billie J.
Published: July 2009

Colonial ascidians are the only chordates to undergo whole body regeneration (WBR), the ability to form an entirely new individual from the peripheral vasculature. Here we describe WBR in Botrylloides violaceus, a colonial ascidian that reliably regenerates after ablation of all zooids and buds of young colonies. During early regeneration several buds develop within the tunic vasculature, but only one continues development into a complete zooid. We describe some of the first events of vascular budding leading to the vesicle stage with phase contrast microscopy, time‐lapse video recording and detailed histological studies of regenerating colonies. The first conspicuous stage of vascular budding is when a single‐layered sphere of cells becomes enclosed by vascular epithelium. We report the appearance of Piwi‐positive cells in hemocytes surrounding the regenerates. We observed an increase of proliferating cell nuclear antigen (PCNA)‐positive cells in circulatory hemocytes in late regenerates, and found double‐labeled nuclear expression with Piwi in a subset of large circulatory cells. We rarely found Piwi or PCNA in differentiating tissues during vascular budding, suggesting that cells that form the epithelial tissues during budding and WBR originate mostly from circulatory hemocyte precursors. We propose that multiple stem cell types are circulating within B. violaceus and that they undergo proliferation in the peripheral vasculature before differentiating into epithelial tissues for all three germ layers during WBR. J. Exp. Zool. (Mol. Dev. Evol.) 312B:885–900, 2009. © 2009 Wiley‐Liss, Inc.
Synthesis and characteristic of 5,6‐dinitro and 5,6‐diaminobenzimidazolone‐2
Authors: Yang Zehui , Wang Jiarong , Li Linglan , Ye Chuping , Liu Hui
Published: July 2009

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5,6‐Dinitro and 5,6‐diaminobenzimidazolone‐2 can be synthesized at a sufficiently high purity and yield to permit its large scale production in an economically feasible manner. The results of our studies derived optimum conditions for the nitration process necessary to obtain pure 5,6‐dinitriobenzimidazolone‐2. J. Heterocyclic Chem. (2009).
Formation of an unusual product in the reaction of a 1,2,5‐thiadiazolidine 1,1‐dioxide‐derived thioether with sulfuryl chloride
Authors: Dou Dengfeng , Talaty Erach R. , Moore Curtis E. , Bullinger John C. , Eichhorn David M. , Groutas William C.
Published: July 2009

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The treatment of a 1,2,5‐thiadiazolidine 1,1‐dioxide‐derived phenylthiomethyl ether with sulfuryl chloride yielded an unexpected dimeric product whose structure was determined using X‐ray crystallography. A plausible mechanism for the formation of this product is proposed. J. Heterocyclic Chem. (2009).
Substituent‐dependence of photophysical properties of trans‐2‐styrylpyridazin‐3(2H)‐ones
Authors: Kim Bo Ram , Cho Su‐Dong , Lee Hyung‐Geun , Yim Heung‐Seop , Kim Min‐Jung , Hwang Jaeyoung , Park Song‐Eun , Kim Jeum‐Jong , Jung Kwang‐Ju , Yoon Yong‐Jin
Published: July 2009

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The photophysical behavior of trans‐2‐styrylpyridazin‐3(2H)‐ones 3 strongly depend on the number and the position of substituents in the phenyl ring in THF, methylene chloride, acetonitrile and methanol. The absorption spectra of 3 containing the electron‐donating substituents at the para‐position show the red‐shift, whereas the spectra of 3 containing the electron‐withdrawing substituents show the blue‐shift. For the trans‐2‐(p‐substituted‐styryl)pyridazin‐3(2H)‐ones 3b, 3c, 3d, 3e, 3f, 3g, 3h and 3k, 3l, 3m, 3n, 3o, the magnitude of the solvatochromic shifts and the shape of the fluorescence spectra depend on the number and/or the position of substituents in benzene ring. The emission maximum of trans‐2‐styrylpyridazin‐3(2H)‐ones involving the electron‐donating group is larger than one of trans‐2‐styrylpyridazin‐3(2H)‐ones involving the electron‐withdrawing group in the phenyl ring. The magnitude of the emission maximum is roughly parallel to the relative electron‐withdrawing ability of the substituents of the phenyl ring. J. Heterocyclic Chem., (2009).
Evaluation of local MCP‐1 and IL‐12 nanocoatings for infection prevention in open fractures
Authors: Li Bingyun , Jiang Bingbing , Dietz Matthew J. , Smith E. Suzanne , Clovis Nina B. , Rao K. Murali Krishna
Published: July 2009

The increasing incidence of bacterial infection and the appearance of Staphylococcus aureus (S. aureus) strains that are resistant to commonly used antibiotics has made it important to develop non‐antibiotic approaches for infection prevention. The aim of this study was to develop local monocyte chemoattractant protein‐1 (MCP‐1) and interleukin‐12 p70 (IL‐12 p70) therapies to prevent S. aureus infection by enhancing the recruitment and activation of macrophages, which are believed to play an important role in infection prevention as the first line of defense against invading pathogens. Nanocoating systems for MCP‐1 and IL‐12 p70 deliveries were prepared, and their release characteristics desirable for infection prevention in open fractures were explored. Local MCP‐1 therapy reduced S. aureus infection and influenced white blood cell populations, and local IL‐12 p70 treatment had a more profound effect on preventing S. aureus infection. No synergistic relationship in decreasing S. aureus infection was observed when MCP‐1 and IL‐12 p70 treatments were combined. This reported new approach may reduce antibiotic use and antibiotic resistance. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:48–54, 2010