bluuebunny/crossref_metadata_2025_split huggingface dataset:
Micro/nanostructural porous surface on titanium and bioactivity
Authors: Gao Ling , Feng Bo , Wang Jianxin , Lu Xiong , Liu Dali , Qu Shuxin , Weng Jie 
Published: October 2008

AbstractPorous surfaces can improve both early fixation and long‐term stabilization of implants by contrast with smooth surfaces. In this study, a microporous surface on titanium was prepared by acid etching and the size of micropores ranged from 1 to 60 μm. The micro/nanostructural porous layer on this microporous surface was obtained by acid etching and anodization. In this micro/nanostructural porous layer, the diameter of nanotubes was about 100 nm. After heat treatment at 450°C for 6 h, the oxides on micro/nanostructural surface transformed into anatase crystals and the grain size of anatase was about 20 nm. The bioactivity of samples was investigated respectively in simulated body fluid and a bovine serum albumin (BSA) solution. The information of specimen surfaces was detected using scanning electron microscope, X‐ray diffractometer, and attenuated total reflection Fourier transform infrared spectroscope. The results showed that the sample with micro/nanostructural porous surface and anatase had excellent bioactivity under nonpretreatment. It had more hydroxyapatite (HA) formation and faster BSA adsorption than other samples under the same conditions. Besides, the HA coating on the micro/nanostructure surface had larger range thickness, no microcrack, and no separated interface from substrate. Therefore, this micro/nanostructural porous surface may be an ideal modification layer for preparing bioactive implants. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Sputtered iridium oxide films for neural stimulation electrodes
Authors: Cogan Stuart F. , Ehrlich Julia , Plante Timothy D. , Smirnov Anton , Shire Douglas B. , Gingerich Marcus , Rizzo Joseph F. 
Published: October 2008

AbstractSputtered iridium oxide films (SIROFs) deposited by DC reactive sputtering from an iridium metal target have been characterized in vitro for their potential as neural recording and stimulation electrodes. SIROFs were deposited over gold metallization on flexible multielectrode arrays fabricated on thin (15 μm) polyimide substrates. SIROF thickness and electrode areas of 200–1300 nm and 1960–125,600 μm2, respectively, were investigated. The charge‐injection capacities of the SIROFs were evaluated in an inorganic interstitial fluid model in response to charge‐balanced, cathodal‐first current pulses. Charge injection capacities were measured as a function of cathodal pulse width (0.2–1 ms) and potential bias in the interpulse period (0.0 to 0.7 V vs. Ag|AgCl). Depending on the pulse parameters and electrode area, charge‐injection capacities ranged from 1–9 mC/cm2, comparable with activated iridium oxide films (AIROFs) pulsed under similar conditions. Other parameters relevant to the use of SIROF on nerve electrodes, including the thickness dependence of impedance (0.05–105 Hz) and the current necessary to maintain a bias in the interpulse region were also determined. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Telomerase‐targeting antisense oligonucleotides carried by polycation liposomes enhance the growth inhibition effect on tumor cells
Authors: Chen Jin‐Liang , Hu Ying , Shuai Wu‐Ping , Chen Hai‐Liang , Liang Wen‐Quan , Gao Jian‐Qing 
Published: October 2008

AbstractIn this study, a novel nonviral gene delivery system, which could enhance the inhibition effect of antisense oligonucleotides (ASODN) against the tumor cells, was developed. The polycation liposomes (PCLs) were prepared using the film hydration method with dioleoylphosphatidylethanolamine (DOPE) and amphipathic compound polyethylenimine‐cholesterol (PEI 800‐Chol), synthesized by low‐molecular‐weight polyethylenimine (PEI, MW 800) covalent conjugation with cholesterol. The formation of PEI 800‐Chol was confirmed by IR and critical micelle concentration detection. The transfection efficiency of PCLs mediating Green Fluorescence Protein plasmid (pEGFP) in HeLa cells was evaluated and the highest gene expression was obtained by PCLs containing DOPE, which was 1.6‐fold of that induced by commercial Lipofectamine™2000, and the gene expression efficiency was influenced in the present of serum. Subsequently, human telomerase reverse transcriptase gene antisense oligonucleotides (hTERT‐ASODN) were used as therapeutic gene, and the results showed that PCLs, which demonstrated very low cytotoxicity itself, could significantly enhance the inhibition efficiency of hTERT‐ASODN in the growth of tumor cells. These results suggested that the PCLs could be widely applied for ASODN delivery. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Partially polyurethane‐covered stent for cerebral aneurysm treatment
Authors: Rangwala Hussain S. , Ionita Ciprian N. , Rudin Stephen , Baier Robert E. 
Published: October 2008

AbstractPartially polyurethane‐covered stent (PPCS) is proposed for the treatment of cerebral aneurysms. The PPCSs were observed to substantially modify the flow entering the aneurysm in a patient‐specific aneurysm phantom (PSAP). These stents can act as flow modulators and the polyurethane (PU) membrane can provide a smooth scaffold for restoring the structural integrity of the diseased vessel. Partial coating of the stent aids in sealing only the entrance to the aneurysm while keeping the perforators around the aneurysm open and patent. Biocompatibility of the PU membrane was monitored using contact angle measurements to show that critical surface tension (CST) values remained in the thromboresistant range of 20–30 mN/m. Stent flexibility, stiffness, and pressure–diameter relationship showed no significant change after asymmetric PU film application. No delamination of the PU membrane from the stent was observed within the working strains of the stent. The flow modulating capability of the PPCS was monitored by intentionally orienting the stent to cover either the proximal or the distal regions along the neck of the PSAP. Time density curves (TDCs) compared the relative metrics of input rate, washout rate, residence time, and influx in the aneurysm before and after the stent placement. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
The study on the degradation and mineralization mechanism of ion‐doped calcium polyphosphate in vitro
Authors: Song Wei , Tian Meng , Chen Feng , Tian Yefei , Wan Changxiu , Yu Xixun 
Published: October 2008

AbstractDoping with different trace elements can significantly change the original degradability, mineralization, and biological properties of bone repair material. According to the fundamental research on prepared calcium polyphosphate (CPP) as a bone repair material by our group, this article began further exploration on the effect of doping different trace elements (K, Na, Mg, Zn, Sr) into CPP on its degradability and mineralization soaking in simulated body fluids. The results indicated that doped elements significantly changed the lattice parameters and cell volume of crystal, resulted in different types of crystal defect and surface charge distribution, and consequently changed the original degradability and mineralization of CPP. The conclusion is that doped ions with relatively smaller ionic radius and equivalent positive charge compared with Ca2+ can greatly promote the degradability and mineralization of CPP, whereas doped ions with equivalent ionic radius and diverse positive charges compared with Ca2+ provide less contribution on promoting the degradability and mineralization or even counteract. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Micro‐computed tomographic analysis of bone healing subsequent to graft placement
Authors: Chopra Preeti M. , Johnson Maria , Nagy Tim R. , Lemons Jack E. 
Published: October 2008

AbstractA micro‐computed tomographic (μCT) analysis of bone healing subsequent to graft (tri calcium phosphate/TCP) placement in the maxillary sinus prior to dental endosteal implant placement was the focus of the current study. Ten trephined rod shaped human bone cores were obtained three months after the placement of particulate graft material. Using the μCT, samples were evaluated at 6 and 20 μm resolutions. The images exhibited regions of different grey scale (GL) magnitudes for bone and graft allowing a differentiation and quantification of the two sample regions. The GL threshold magnitudes at 20 μm resolution were determined to be less than 235 for organic and fluid, 235–450 for bone, 400–600 for bone and graft, and 600 and above for the graft material. The graft material was integrated with the bone showing the osteoconductivity of the TCP material, the mean bone volume was 25.50 (11.28) ranging from 5.66 to 37.9 and the mean graft volume was 0.42 (0.37) ranging from 0.01 to 1.17. The mean graft to bone volume ratio was 0.015 (0.01) with a range from 0.002 to 0.024. The structural data and observations from two‐ and three‐dimensional images provided a valuable assessment of the graft distribution, its relation to modeling bone and also the anatomy of the healing bone. Thus this study demonstrated the capability to uniquely evaluate the status of healing bone associated with this TCP grafting biomaterial with opportunities for subsequent correlations with histomorphometrical studies and clinical outcomes of these type implant treatments. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Potential of chemically modified hydrophilic surface characteristics to support tissue integration of titanium dental implants
Authors: Schwarz Frank , Wieland Marco , Schwartz Zvi , Zhao Ge , Rupp Frank , Geis‐Gerstorfer Jürgen , Schedle Andreas , Broggini Nina , Bornstein Michael M. , Buser Daniel , Ferguson Stephen J. , Becker Jürgen , Boyan Barbara D. , Cochran David L. 
Published: October 2008

AbstractIn the past, several modifications of specific surface properties such as topography, structure, chemistry, surface charge, and wettability have been investigated to predictably improve the osseointegration of titanium implants. The aim of the present review was to evaluate, based on the currently available evidence, the impact of hydrophilic surface modifications of titanium for dental implants. A surface treatment was performed to produce hydroxylated/hydrated titanium surfaces with identical microstructure to either acid‐etched, or sand‐blasted, large grit and acid‐etched substrates, but with hydrophilic character. Preliminaryin vitrostudies have indicated that the specific properties noted for hydrophilic titanium surfaces have a significant influence on cell differentiation and growth factor production. Animal experiments have pointed out that hydrophilic surfaces improve early stages of soft tissue and hard tissue integration of either nonsubmerged or submerged titanium implants. This data was also corroborated by the results from preliminary clinical studies. In conclusion, the present review has pointed to a potential of hydrophilic surface modifications to support tissue integration of titanium dental implants. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Evaluation of focal fatty infiltration of the liver using color Doppler and contrast‐enhanced sonography
Authors: Liu Li‐Ping , Dong Bao‐Wei , Yu Xiao‐Ling , Zhang Da‐Kun , Kang Chun‐Song , Zhao Xi‐Hai 
Published: October 2008

AbstractPurpose.To investigate the vascular characteristics of focal fatty infiltration (FFI) in the liver using color Doppler sonography (CDUS) and contrast‐enhanced sonography (CEUS).Methods.We prospectively examined 25 areas of FFI of the liver in 20 patients via conventional gray‐scale sonography, CDUS, and CEUS. Cadence contrast pulse sequencing and the contrast agent SonoVue were used for CEUS examination. CEUS criteria for diagnosis of FFI were isoenhancement or hypoenhancement in the arterial phase and homogeneous isoenhancement in the portal and late phases.Results.CDUS revealed a draining vein in 4 of 9 (44%) lesions in the hepatic hilum, whereas CEUS revealed a draining vein in 8 (89%) lesions. A vein was associated with the 2 lesions located at the edge of segment II on both CDUS and CEUS. Blood flow was seen on both CDUS and CEUS in the 2 lesions adjacent to the falciform ligament. In one patient, CDUS and CEUS revealed the mid‐hepatic vein coursing between 2 FFIs. In the arterial phase of CEUS, the lesions were hypoenhancing in 44% (11/25), iso‐enhancing in 44% (11/25), and hyperenhancing in 12% (3/25). In the portal phase and in the late vascular phase, all 25 lesions (100%) were iso‐enhancing. Sensitivity of combined sonography and CDUS in the diagnosis of FFI was 44%, and overall accuracy was 81%. The sensitivity of CEUS in the diagnosis of FFI was 88%, and its overall accuracy was 96%.Conclusion.FFI in the porta hepatis is correlated with aberrant venous drainage. FFI around the falciform ligament may be related to divergence of the portal vein or unusual blood supply. In the arterial phase of CEUS, FFI lesions were iso‐enhancing as often as they were hypoenhancing. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Thanatophoric dysplasia: Role of 3‐dimensional sonography
Authors: Tsai Pei‐Yin , Chang Chiung‐Hsin , Yu Chen‐Hsiang , Cheng Yueh‐Chin , Chang Fong‐Ming 
Published: October 2008

AbstractPurpose.Fetal thanatophoric dysplasia (TD) is a lethal skeletal dysplasia. Therefore, antenatal diagnosis of TD is mandatory in routine obstetrical care. However, because TD is relatively rare, prenatal detection is not an easy task. In the past, 2‐dimensional (2D) sonography had been applied as the mainstay of prenatal diagnosis of TD. In this series, we report our work of detecting TD using 3‐dimensional (3D) sonography.Methods.We reviewed our computer database of prenatal diagnosis of TD in National Cheng Kung University Hospital from May 1995 to June 2006. All the cases were scanned using 2D and 3D sonography. In total, 9 cases of fetal TD were diagnosed.Results.3D sonography can detect fetal TD and provide additional vivid illustration after various modes of reconstruction that 2D sonography cannot afford.Conclusion.3D sonography may contribute significantly to the detection of TD in utero and provide a novel visual depiction of this defect after reconstruction. Thus, 3D sonography may assist substantially in prenatal diagnosis as well as consultation. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009
Electron tomography study of isolated human centrioles
Authors: Ibrahim Rana , Messaoudi Cédric , Chichon Francisco Javier , Celati Claude , Marco Sergio 
Published: October 2008

AbstractCentrioles are components of the centrosome, which is present in most eukaryotic cells (from protozoa to mammals). They organize the microtubule skeleton during interphase and the mitotic spindle during cell division. In ciliate cells, centrioles form basal bodies that are involved in cellular motility. Despite their important roles in biology, the detailed structure of centrioles remains obscure. This work contributes to a more complete model of centriole structure. The authors used electron tomography of isolated centrosomes from the human lymphoblast KE37 to explore the details of subdistal appendages and centriole lumen organization in mother centrioles. Their results reveal that each of the nine subdistal appendages is composed of two halves (20 nm diameter each) fused in a 40 nm tip that extends 100 nm from where it anchors to microtubules. The centriole lumen is filled at the distal domain by a 45 nm periodic stack of rings. Each ring has a 30 nm diameter, is 15 nm thick, and appears to be tilted at 53° perpendicular to the centriole axis. The rings are anchored to microtubules by arms. Based on their results, the authors propose a model of the mother centriole distal structure. Microsc. Res. Tech., 2009. © 2008 Wiley‐Liss, Inc.
Quantitative X‐ray microanalysis of hydrogen peroxide within plant cells
Authors: Chen Shaoliang , Olbrich Andrea , Langenfeld‐Heyser Rosemarie , Fritz Eberhard , Polle Andrea 
Published: October 2008

AbstractUsing quantitative X‐ray microanalysis in combination with CeCl3‐based cytochemical staining of hydrogen peroxide (H2O2) we have developed a new solution for quantification of H2O2 at the subcellular level. Quantitative X‐ray microanalysis of plastic‐embedded leaves of Populus euphratica Oliv. showed that the obtained cerium precipitates by CeCl3 staining were the mixture of cerium perhydroxides and cerium phosphate, in which the fractions of CePO4 were: (1) 52–74% in cell walls of fresh leaf segments, and (2) 34–70% in the cytoplasm in 10 mM H2O2‐treated leaf segments that were previously freeze‐dried. Taking the concentration of cerium phosphate as staining background, we reached the cellular concentration of cerium perhydroxides and the corresponding concentration of H2O2. Results showed that H2O2 was present in the cytoplasm of rehydrated leaf segments (29–58 mM), but in fresh leaves, H2O2 was observed in the walls of all measured cell types (17–74 mM). Microsc. Res. Tech., 2009. © 2008 Wiley‐Liss, Inc.
Morphometric characteristics of choroid plexus epithelial cells in cases with significantly different psammoma bodies' presence
Authors: Jovanović Ivan , Ugrenović Sladjana , Vasović Ljiljana , Čukuranović Rade , Stoiljković Nenad 
Published: October 2008

AbstractObjectives: Taking into the consideration the fact that psammoma bodies have never been observed in stroma of any other organ as aging change, the aim of our research was to prove some structural similarities of choroids plexus and tumors psammoma bodies, and their possible connection with choroids plexus epithelial cells atrophy. Materials and Methods: We used 30 cadavers' right lateral ventricle central parts of choroid plexus as material. Tissue samples were routinely processed for the applied histochemical and immunohistochemical stainings. ImageJ software was used for morphometric analysis. Results: Cluster analysis showed the presence of two significantly different groups. The first group included the cases with sparse psammoma bodies and milder epithlelial atrophy with dome cells and vacuoles presence in older cases. The second group included the cases with numerous psammoma bodies and more severe epithelial atrophy, significant cystic formations and epithelial flattening presence, even in younger cases. Immunohistochemical analysis showed positive reaction of psammoma bodies and choroid plexus stroma on S100 protein. Application of S100 A8/A9 marker showed partial positive psammoma bodies' reaction and significant presence of S100 A8/A9 positive cells in choroid plexus blood vessels and stroma, especially, in cases with psammoma bodies' positive reaction on this marker. Conclusions: So, presence of more numerous psammoma bodies' might be associated with more severe choroids plexus epithelial cells atrophy. Immunohistochemical analysis showed psammoma bodies' positive reaction on S100 protein and the presence of S100 A8/A9 positive cells in stroma of cases with psammoma bodies' positive reaction on this marker. Microsc. Res. Tech., 2009. © 2008 Wiley‐Liss, Inc.
Well‐ordered structure of methylene blue monolayers on Au(111) surface: Electrochemical scanning tunneling microscopy studies
Authors: Song Yonghai , Wang Li 
Published: October 2008

AbstractWell‐ordered structure of methylene blue (MB) monolayers on Au(111) surface has been successfully obtained by controlling the substrate potential. Electrochemical scanning tunneling microscopy (ECSTM) examined the monolayers of MB on Au(111) in 0.1 M HClO4 and showed long‐range ordered, interweaved arrays of MB with quadratic symmetry on the substrate in the potential range of double‐layer charging. High‐resolution ECSTM image further revealed the details of the MB monolayers structure of c(5 × 5√3)rect and the flat‐lying orientation of ad‐molecules. The dependence of molecular organization on the substrate potential and the formation mechanism of well‐ordered structure on Au(111) surface were investigated in detail. The obtained well‐ordered structure at the interface between a metal and an aqueous electrolyte might possibly be used as high‐density device for signal memory and templates for the advanced nanopatterning of surfaces. Microsc. Res. Tech., 2009. © 2008 Wiley‐Liss, Inc.
Reductive amination as a strategy to reduce adenovirus vector promiscuity by chemical capsid modification with large polysaccharides
Authors: Espenlaub Sigrid , Wortmann Andreas , Engler Tatjana , Corjon Stéphanie , Kochanek Stefan , Kreppel Florian 
Published: October 2008

AbstractBackgroundChemical capsid modification of adenovirus vectors with synthetic polymers has been shown to aid in overcoming typical barriers for adenovirus vector‐mediated gene transfer. Carbohydrate‐based polymers for covalent modification of adenovirus vectors have been largely neglected so far. We utilized a reductive amination strategy to generate a novel class of adenovirus‐based glycovectors with a mannan derivative.MethodsReductive amination to covalently couple polysaccharides to the capsid surface of adenovirus serotype 5‐based vectors was investigated utilizing an oxidized derivative of mannan. After biochemical and physical characterization of mannanylated vectors, their performance was analysed in vitro in cell lines and primary human cells, and in vivo in mice after local and systemic vector injection.ResultsWe describe the successful modification of adenovirus vectors with large polysaccharides by reductive amination. The particles were efficiently modified, physically intact and, importantly, detargeted from the natural Coxsackie and adenovirus receptor/integrin pathway in vitro. In addition, they exhibited significantly decreased transduction of muscle after local delivery and of liver after systemic delivery in mice. However, despite the modification of 60% of capsid surface amino groups, mannanylated particles were unable to evade neutralizing anti‐Ad5 antibodies.ConclusionsMannanylated vectors are a paradigm for a novel class of glycoviruses modified with large polysaccharides. Vector promiscuity as one of the important hurdles for Ad‐mediated gene transfer could be significantly decreased in vivo, whereas mannanylated vectors were unable to escape from anti‐adenovirus antibodies. Our studies provide a detailed analysis of mannan‐modified Ad vectors and suggest further improvements for this novel class of glycovectors. Copyright © 2008 John Wiley & Sons, Ltd.
A reversal of educational fortune? Educational gender gaps in Bangladesh
Authors: Shafiq M. Najeeb 
Published: October 2008

AbstractHistorically, educational gender gaps in Bangladesh persisted as households invested more in the education of boys than girls. Recent anecdotal and descriptive reports, however, claim that Bangladesh has achieved gender parity in education. Using advanced empirical methods and nationally representative data, this study finds that urban and rural boys (relative to urban and rural girls) have a 7.4–27.4% lower likelihood of being enrolled in school, 0.4–1.5 fewer years of educational attainment and 9.7–30.8% lower likelihood of being literate. These findings draw attention to the causes of the reversal in the educational gender gap in Bangladesh. Copyright © 2008 John Wiley & Sons, Ltd.
Governance and foreign aid in Pacific Island countries
Authors: Gani Azmat 
Published: October 2008

AbstractThis paper examines the relationship between indicators of governance and per capita foreign aid in a cross‐section of seven PICs. Controlling for poor economic growth, foreign exchange shortage and small size, a fixed‐effects model correcting for AR (1) errors is tested for the period 1996–2004 that incorporates five measures of governance. The findings here confirm that voice and accountability, rule of law and corruption are negatively correlated with per capita foreign aid. However, regulatory quality and government effectiveness are positively associated with per capita foreign aid. Some policy implications are drawn. Copyright © 2008 John Wiley & Sons, Ltd.