bluuebunny/crossref_metadata_2025_split huggingface dataset:
Composite nanofiber mats consisting of hydroxyapatite and titania for biomedical applications
Authors: Kim Hong Mi , Chae Won‐Pyo , Chang Ki‐Whan , Chun Sungsu , Kim Sukyoung , Jeong Yongsoo , Kang Inn‐Kyu 
Published: June 2010

AbstractComposite nanofiber mats (HA/TiO2) consisting of hydroxyapatite (HA) and titania (TiO2) were fabricated via an electrospinning technique and then collagen (type I) was immobilized on the surface of the HA/TiO2composite nanofiber mat to improve tissue compatibility. The structure and morphology of the collagen‐immobilized composite nanofiber mat (HA/TiO2‐col) was investigated using an X‐ray diffractometer, electron spectroscopy for chemical analysis, and scanning electron microscope. The potential of the HA/TiO2‐col composite nanofiber mat for use as a bone scaffold was assessed by an experiment with osteoblastic cells (MC3T3‐E1) in terms of cell adhesion, proliferation, and differentiation. The results showed that the HA/TiO2‐col composite nanofiber mats possess better cell adhesion and significantly higher proliferation and differentiation than untreated HA/TiO2composite nanofiber mats. This result suggests that the HA/TiO2‐col composite nanofiber mat has a high‐potential for use in the field of bone regeneration and tissue engineering. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
Preparation, microstructures, mechanical properties, and cytocompatibility of TiMn alloys for biomedical applications
Authors: Zhang Faming , Weidmann Arne , Nebe J. Barbara , Beck Ulrich , Burkel Eberhard 
Published: June 2010

AbstractThe titanium‐manganese (TiMn) alloys have been extensively used in aerospace and hydrogen storage. In this study, the TiMn alloys with various manganese contents ranging from 2 to 12 wt % were prepared by using mechanical alloying and spark plasma sintering (SPS) techniques. The microstructures, mechanical properties including hardness, elastic modulus and ductility, cytotoxicity and cell proliferation properties of the TiMn alloys were investigated to explore their biomedical applications. The addition of manganese to the titanium reduced the α to β transformation temperature and was confirmed as a β stabilizer element. The manganese increased the relative density of the alloy and thus high density TiMn alloys with α+β structure were prepared by using SPS at 700°C. The hardness increased significantly ranging from 2.4 GPa (Ti2Mn) to 5.28 GPa (Ti12Mn) and the elastic modulus ranging from 83.3 GPa (Ti2Mn) to 122 GPa (Ti12Mn), the ductility decreased ranging from 21.3% (Ti2Mn) to 11.7% (Ti12Mn) with increasing manganese content in the Ti. Concentrations of Mn below 8 wt % in titanium reveal negligible effects on the metabolic activity and the cell proliferation of human osteoblasts. The Mn could be used in lower concentrations as an alloying element for biomedical titanium. The Ti2Mn, Ti5Mn, and Ti8Mn alloys with supervisor mechanical properties and acceptable cytocompatibility have a potential for use as bone substitutes and dental implants. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
In vitro performance assessment of new brushite‐forming Zn‐ and ZnSr‐substituted β‐TCP bone cements
Authors: Pina S. , Vieira S.I. , Torres P. M. C. , Goetz‐Neunhoeffer F. , Neubauer J. , da Cruz e Silva O. A. B. , da Cruz e Silva E. F. , Ferreira J. M. F. 
Published: June 2010

AbstractThe present study investigated the in vitro performance of brushite‐forming Zn‐ and ZnSr‐substituted β‐TCP bone cements in terms of wet mechanical strength and biological response. Quantitative phase analysis and structural refinement of the powdered samples were performed by X‐ray powder diffraction and Rietveld refinement technique. Initial and final setting times of the cement pastes, measured using Gilmore needles technique, showed that ZnSrCPC sets faster than ZnCPC. The measured values of the wet strength after 48 h of immersion in PBS solution at 37°C showed that ZnSrCPC cements are stronger than ZnCPC cements. Human osteosarcoma‐derived MG63 cell line proved the nontoxicity of the cement powders, using the resazurin metabolic assay. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
Three‐dimensional ultrasound inversion rendering technique facilitates the diagnosis of hydrosalpinx
Authors: Timor‐Tritsch Ilan E. , Monteagudo Ana , Tsymbal Tanya 
Published: June 2010

AbstractPurpose.To test the utility of three‐dimensional (3D) ultrasound (US) inversion rendering technique in the evaluation of fluid‐distended fallopian tubes.Methods.Fifty‐two patients with fluid‐filled adnexal masses suspected of being abnormal fallopian tubes were scanned by two‐dimensional and 3D transvaginal ultrasound (TVUS). Six patients had bilateral disease. The acquired volumes were then “inverted” to display a cast‐like appearance of the fluid‐filled structures. The ipsilateral ovaries were identified in all patients. Five patients had acute tubal disease.Results.Fifty‐two of the 58 inversion renderings yielded acceptable images of hydrosalpinges. Only in four patients were the two‐dimensional images more informative than the 3D‐rendered and inverted views. In nine patients adjacent corpora lutea, ovarian cysts, and follicles within normal ovaries were also identified, but appeared separate from the fluid‐filled tubes. The tubes in the patients with acute disease were all successfully inverted.Conclusions.The 3D inversion technique is a simple and effective way to render fluid‐filled spaces, which may be tortuous and follow various directions. The rendered images increased the confidence in diagnosing hydrosalpinx. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:372‐376, 2010
Ultrasound training for medical students and internal medicine residents—A needs assessment
Authors: Kessler Chad , Bhandarkar Stephen 
Published: June 2010

AbstractPurposeWhile sonography has been a mainstay of certain medical specialties, such as obstetrics and gynecology, internal medicine has been slower to integrate this technology into practice. No standardized training in sonography exists for either medical students or internal medicine residents, and little is known about the current competency and utilization of ultrasound among these groups. The goal of this article is to examine the present state of ultrasound education among internal medicine residents and medical students at a major university hospital.MethodsThird‐year medical students from the University of Illinois at Chicago and senior medicine residents from University of Illinois at Chicago and Northwestern University were invited to complete a Likert‐type survey regarding their attitudes, competence, and interest in ultrasound, the nature of previous training, and areas where incorporation of ultrasound would be useful.ResultsOne hundred sixty‐three students and 40 residents participated (81.8% response rate). Students and residents generally felt incompetent in the use of ultrasound; objective competency in the resident group, as evaluated by an emergency physician certified by the American College of Emergency Physicians, was equally low. However, interest in additional training was high. Nearly 50% of the respondents had no prior sonography training; however, those with previous training rated it highly. Areas in which sonography was most sought‐after include central line placement, paracentesis, and thoracentesis.ConclusionsThere is a clear desire for training in sonography among the medical students and internal medicine residents surveyed. As ultrasound is further integrated into clinical practice, students and residents would strongly benefit from formal didactic and hands‐on training in the modality. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:401–408, 2010
Fast analysis of phenolic acids by electrokinetic supercharging‐nonaqueous capillary electrophoresis
Authors: Lu Yuanqi , Breadmore Michael C. 
Published: June 2010

AbstractA method was developed to analyze phenolic acids by nonaqueous CE after online concentration with electrokinetic supercharging. The EOF was reversed using a polyelectrolyte multilayer approach based on the successive adsorption of poly(diallyldimethylamonium chloride) and poly(styrenesulfonate) to reduce the analysis time. The results showed that the coatings were stable during 40 consecutive injections. Four phenolic acids were separated within 8 min using 30 mM ammonium acetate (pH* 8.0). The electrokinetic injection time and terminator length of the electrokinetic supercharging method were optimized to improve the detection sensitivity. Under the optimized conditions (electrokinetic injection of 100 s, −10 kV; terminator of 20 mM 2‐(cyclohexylamino) ethanesulfonic acid, 22 s, 0.5 psi), the sensitivity was enhanced from 300‐ to 440‐fold. The detection limits, based on three times noise, were in the range 1.0–2.5 ng/mL.
Nano and rapid resolution liquid chromatography–electrospray ionization–time of flight mass spectrometry to identify and quantify phenolic compounds in olive oil
Authors: García‐Villalba Rocío , Carrasco‐Pancorbo Alegría , Zurek Gabriela , Behrens Marina , Bäßmann Carsten , Segura‐Carretero Antonio , Fernández‐Gutiérrez Alberto 
Published: June 2010

AbstractThe applicability of nanoLC‐ESI‐TOF MS for the analysis of phenolic compounds in olive oil was studied and compared with a HPLC method. After the injection, the compounds were focused on a short capillary trapping column (100 μm id, effective length 20 mm, 5 μm particle size) and then nanoLC analysis was carried out in a fused silica capillary column (75 μm id, effective length 10 μm, 3 μm particle size) packed with C18 stationary phase. The mobile phase was a mixture of water + 0.5% acetic acid and ACN eluting at 300 nL/min in a gradient mode. Phenolic compounds from different families were identified and quantified. The quality parameters of the nanoLC method (linearity, LODs and LOQs, repeatability) were evaluated and compared with those obtained with HPLC. The new methodology presents better sensitivity (reaching LOD values below 1 ppb) with less consumption of mobile phases, but worse repeatability, especially inter‐day repeatability, resulting in more difficulties to get highly accurate quantification. The results described in this article open up the application fields of this technique to cover a larger variety of compounds and its advantages will make it especially useful for the analysis of samples containing low concentration of phenolic compounds, as for instance, in biological samples.
The analytical resolution of parallel first‐ and second‐order reaction mechanisms
Authors: Caballero N. B. , Croce A. E. , Pensa E. , Irrazábal C. Vicente 
Published: June 2010

AbstractGiven the species A1 and A2, the competition among the three different elementary processes

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is frequently found in thermal and photochemical reaction systems. In the present paper, an analytical resolution of the system (1)–(3), performed under plausible contour conditions, namely, finite initial molar concentrations for both reactants, [A2]0 and [A1]0, and nonzero reaction rate coefficients k1, k2, and k3, leads to the equation [A1] = ((δ[A2]γ − [A2])/β) − α, where α = k1/2k3, γ = β + 1 = 2k3/k2, and δ = ([A2]0 + β[A1]0 + β α))/[A2]0γ.The comparison with a numerical integration employing the fourth‐order Runge–Kutta algorithm for the well‐known case of the oxidation of organic compounds by ferrate ion is performed. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 562–566, 2010
The real danger of lamivudine-resistant hepatitis B virus infection in the immunocompromised host
Authors: Vargas Hugo E. 
Published: June 2010

AbstractBackground:In many transplant centres lamivudine is an important component of prophylaxis against, and treatment of, hepatitis B virus (HBV) graft infection. Drug resistant HBV species with specific polymerase mutations may emerge during lamivudine treatment.Aims:To examine the clinical consequences of graft infection by lamivudine resistant virus.Methods:The clinical course of four liver transplant patients who developed graft infection with lamivudine resistant virus was reviewed. The response of HBV infection to reduction of immunosuppression and to manipulation of antiviral therapy was assessed. For each patient, serum viral titre was measured and the viral polymerase gene was sequenced at multiple time points.Results:High serum titres were observed following emergence of the lamivudine resistant species. Wild type HBV re-emerged as the dominant serum species after lamivudine withdrawal. All patients developed liver failure, and onset of liver dysfunction was observed when resistant virus was the dominant serum species. In three patients, liver recovery was observed when immunosuppression was stopped and when alternative antivirals were given. Wild type virus appeared to respond to ganciclovir, and to reintroduction of lamivudine. For one patient, introduction of famciclovir was associated with clinical, virological, and histological response.Conclusions:Failure of lamivudine prophylaxis may identify patients at special risk for the development of severe graft infection. Treatment of graft reinfection should include reduction of immunosuppression, and systematic exposure to alternative antivirals. Viral quantitation and genetic sequencing are essential components of therapeutic monitoring.
Around the world with the model for end-stage liver disease
Authors: Freeman Richard B. 
Published: June 2010

Abstract

Background:
Indices for predicting survival are essential for assessing prognosis and assigning priority for liver transplantation in patients with liver cirrhosis. The model for end stage liver disease (MELD) has been proposed as a tool to predict mortality risk in cirrhotic patients. However, this model has not been validated beyond its original setting.

Aim:
To evaluate the short and medium term survival prognosis of a European series of cirrhotic patients by means of MELD compared with the Child-Pugh score. We also assessed correlations between the MELD scoring system and the degree of impairment of liver function, as evaluated by the monoethylglycinexylidide (MEGX) test.

Patients and methods:
We retrospectively evaluated survival of a cohort of 129 cirrhotic patients with a follow up period of at least one year. The Child-Pugh score was calculated and the MELD score was computed according to the original formula for each patient. All patients had undergone a MEGX test. Multivariate analysis was performed on all variables to identify the parameters independently associated with one year and six month survival. MELD values were correlated with both Child-Pugh scores and MEGX test results.

Results:
Thirty one patients died within the first year of follow up. Child-Pugh and MELD scores, and MEGX serum levels were significantly different among patients who survived and those who died. Serum creatinine, international normalized ratio, and MEGX60 were independently associated with six month mortality while the same variables and the presence of ascites were associated with one year mortality. MELD scores showed significant correlations with both MEGX values and Child-Pugh scores.

Conclusions:
In a European series of cirrhotic patients the MELD score is an excellent predictor of both short and medium term survival, and performs at least as well as the Child-Pugh score. An increase in MELD score is associated with a decrease in residual liver function.
A Simple Method for Cell Sheet Fabrication Using Mica Surfaces Grafted with Peptide Detergent A6K
Authors: Qiu Feng , Chen Yongzhu , Cheng Jingqiu , Wang Chen , Xu Hongyan , Zhao Xiaojun 
Published: June 2010

AbstractCell sheet technology is a very important strategy for scaffold‐free tissue engineering. In order to fabricate cell sheets by a simple method, peptide detergent A6K was grafted on mica surfaces by dropping its aqueous solution at different concentrations on the surface. As revealed by surface topographical observation and water contact angle measurement, the most hydrophobic surface was obtained using peptide solution at the concentration of 0.2 mg · mL−1. The peptide‐grafted mica surface was used to culture mouse preosteoblast cell MC3T3‐E1. After the cells reached confluence and the peptide was biodegraded, an intact cell sheet was peeled from the mica. This simple method does not need any non‐biological reagents or complicated procedures, and may have great potential in tissue engineering based on cell sheet technology.magnified image
Microparticles for Drug Delivery Based on Functional Polycaprolactones with Enhanced Degradability: Loading of Hydrophilic and Hydrophobic Active Compounds
Authors: Vaida Cristian , Mela Petra , Kunna Katharina , Sternberg Katrin , Keul Helmut , Möller Martin 
Published: June 2010

AbstractMicroparticle drug carriers made of biodegradable functional polyesters were produced. The polyesters consist of a poly(ε‐caprolactone) backbone bearing pendant acryloyloxy and methacryloyloxy groups. Stable microparticles were prepared via an oil/water emulsion‐solvent evaporation technique eventually combined with a simultaneous crosslinking procedure. Crosslinked particles were obtained via photo‐crosslinking and Michael type addition using diamines as crosslinking agents. Encapsulation of a hydrophobic fluorescent dye and a hydrophilic protein, as model drugs, were performed and confirmed by optical microscopy and Raman spectroscopy. The presence of the functional groups allow for not only the tuning of the degradation rate, but also for further processing and (bio)functionalization.magnified image
The Softer and More Hydrophobic the Better: Influence of the Side Chain of Polymethacrylate Nanoparticles for Cellular Uptake
Authors: Lorenz Steffen , Hauser Christoph P. , Autenrieth Benjamin , Weiss Clemens K. , Landfester Katharina , Mailänder Volker 
Published: June 2010

AbstractIntracellular uptake of nanoparticles is highly interesting for labeling of cells, drug delivery, or non‐viral gene delivery. In this study we have synthesized a wide variety of poly(alkyl methacrylate) nanoparticles with the same size and investigated their uptake into cells. The nanoparticles were prepared from alkylmethacrylates with different linear and branched ester chains as well as from benzylmethacrylate using the miniemulsion polymerizaiton technique. By adding a fluorescent dye as a marker, the internalization of the nanoparticles could be investigated quantitatively with flow cytometry and qualitatively with confocal laser scanning microscopy. With increasing side chain of the ester and therefore increasing hydrophobicity and at glass transition temperature (Tg), below the incubation temperature of 37 °C the uptake of the nanoparticles into cells is favored.
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Bioresorbable Electrospun Fibers for Immobilization of Thiol‐Containing Compounds
Authors: Lösel Robert , Grafahrend Dirk , Möller Martin , Klee Doris 
Published: June 2010

AbstractFor the reconstruction of functional tissue, biodegradable scaffolds providing specific surface functionality and a three‐dimensional structure matching that of the damaged tissue are needed. Fibers capable of controlling cell‐fiber interaction were produced by electrospinning of PDLLA‐block‐PEG with thiol‐reactive end groups from a solvent mixture. The hydrophilic fibers uniquely combine minimized non‐specific protein adsorption and well‐defined surface reactivity allowing controlled immobilization of peptides and proteins. Human dermal fibroblasts show adherence and proliferation on the surface of RGDC‐functionalized electrospun PDLLA‐block‐PEG fibers.magnified image
Enhanced Stereocomplexation by Enantiomer Adjustment for Stereo Diblock Polylactides with Non‐Equivalent D/L Ratios
Authors: Hirata Masayuki , Kobayashi Kaori , Kimura Yoshiharu 
Published: June 2010

AbstractA stereo diblock polylactide di‐sb‐PLA consisting of PDLA and PLLA in a block ratio of 2:8 was prepared and mixed with PDLA to investigate the effect of enantiomer adjustment on the sc crystallinity. Each of these polymer blends was found to have improved stereocomplexibility which was changed with the PDLA compositions in the di‐sb‐PLA/PDLA blend systems. It was also revealed that melt blending is more highly efficient than solution blending in terms of enhancing the sc crystallinity. The blend samples prepared by the former process were found to retain high loss modulus above Tg as well as heat‐stability up to Tm (215 °C) of di‐sb‐PLA. These data hold promise for interesting applications of di‐sb‐PLA and its polymer blends as high‐performance bio‐based materials.magnified image
Characterization and Properties of Poly[N‐(2‐cyanoethyl)pyrrole]
Authors: Aradilla David , Estrany Francesc , Armelin Elaine , Oliver Ramon , Iribarren José I. , Alemán Carlos 
Published: June 2010

AbstractPNCPy was prepared by anodic polymerization and its properties in both doped and undoped state were characterized. The doping level of the oxidized material has been found to be larger than that of other conducting polymers; the more relevant electrochemical properties of the doped material were retained after undoping. SEM and AFM data are consistent with a lumpy surface and a multidirectional growing of the polymer chains. Finally, PNCPy has been combined with PEDOT to prepare three‐layer systems with enhanced electroactivity and electrostability. Results suggest that PNCPy is a potential candidate for the fabrication of electric circuit components that are able to block the current flow below a given potential.magnified image
Relaxation Processes of Poly(tert‐butyl acrylate) Chemically Confined via Hydrogen Bonds
Authors: Schwabe Moritz , Rotzoll Robert , Küchemann Stefan , Nadimpalli Karthik , Vana Philipp , Samwer Konrad 
Published: June 2010

AbstractIn this work, tailored copolymers of tert‐butyl acrylate and acrylic acid (AA) with an ABA type structure were systematically analyzed via dynamic‐mechanical analysis with regard to their relaxations, in which the main focus was put on a chemical confinement (cc) mode caused by hydrogen bonds. Four different relaxation modes were detected, whereupon two modes seem to depend on the length of the inner B‐block and one on the length of the outer A‐blocks. One mode below room temperature could be identified as a secondary relaxation which belongs to the B‐block and is most likely induced by a cc. A softening of the polymer corresponding to the glass transition is found near to room temperature and surprisingly shifts to lower temperatures with increasing chain length of the B‐block. A second softening of the ABA type copolymers is caused by the AA containing A‐blocks and was found at higher temperatures.magnified image
Nanoporous Films with Low Refractive Index for Large‐Surface Broad‐Band Anti‐Reflection Coatings
Authors: Wicht Gaëtan , Ferrini Rolando , Schüttel Stefan , Zuppiroli Libero 
Published: June 2010

AbstractNowadays, nanoporous films are widely employed in biochemical applications or in opto‐photonic devices such as displays, solar cells, or light‐guiding systems. In particular, the technological feasibility of nanoporous layers with low refractive indices has recently enabled the development of high‐efficiency anti‐reflection coatings. In this paper, we report on hybrid polymer nanoporous films that can be fabricated in a single coating step with an industrial aqueous‐based method on very large surfaces. Both high transparency and low refractive index are simultaneously achieved over the entire visible spectrum. We eventually demonstrate the potential of such films for broadband AR applications by combining them in a graded‐index multilayer that reduces the surface reflectivity of a polymer substrate from 10% to few ‰.magnified image