bluuebunny/crossref_metadata_2025_split huggingface dataset:
Porous tantalum in hip and knee reconstructive surgery
Authors: Patil Nilesh , Lee Kevin , Goodman Stuart B. 
Published: October 2008

AbstractConventional porous‐coated joint prostheses used in hip and knee reconstruction have demonstrated good clinical results, however, these implants possess some inherent shortcomings such as low volumetric porosity, suboptimal frictional characteristics, and higher modulus of elasticity relative to that of bone. Porous tantalum, a novel porous biomaterial was developed to address these limitations. Extensive laboratory studies have revealed that porous tantalum has physical, mechanical and tissue in growth properties that makes it a potentially improved biomaterial particularly in complex joint reconstructions. Porous tantalum is a highly porous biomaterial with good biocompatibility, excellent corrosion resistance, and high coefficient of friction. The short term clinical results of porous tantalum in primary hip, revision hip, and knee reconstructive surgery are encouraging but further studies will be needed to determine whether the theoretical advantages of porous tantalum can provide long term biological fixation and stability. This review presents the biomaterial properties and clinical results of porous tantalum devices in hip and knee reconstructive surgeries. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Observations on an in‐vivo failure of a titanium dental implant/abutment screw system: A case report
Authors: Manda Marianthi G. , Psyllaki Pandora P. , Tsipas Dimitrios N. , Koidis Petros T. 
Published: October 2008

AbstractTitanium and its alloys are widely used in prosthetic dentistry, due to their biocompatibility, excellent mechanical and anti‐corrosion behavior. However, delayed fracture of dental prosthetics is frequently encountered. Mechanisms leading to fracture are not generic but are strongly related to the particular environmental (quality of biological fluids) and mechanical loading conditions (mastication habits, presence of prosthetic metallic/ceramic components) in the patients' oral cavity. In this study, a commercially pure titanium implant‐screw system has failed after 15 years of operation in the oral cavity of an old female. The system was retrieved in three pieces: the upper part of the implant, part of the abutment screw, and the apical part of the implant to which a part of the screw was embedded. This is considered as a rare case, where the whole dental assembly was retrieved after fracture allowing the extensive fractographic analysis of the conjugate pieces and the establishment of a thorough in‐vivo failure scenario. Scanning electron microscopy observations performed on all three retrieved parts indicated a synergistic effect of distinct mechanisms, which led to total failure under extrinsic common fatigue loading. The principal mechanism was the propagation of a main crack, which was previously initiated in the body of the implant and affected by a wedging mechanism due to Ca/P aggregates developed within the crack. Because of the strong fixation between the implant and the abutment screw, this main crack was transferred to the latter causing eventually total failure of the assembly. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
The new adhesion prophylaxis membrane A‐part®—From in vitro testing to first in vivo results
Authors: Jaenigen Bernd Martin , Weis Christine , Odermatt Erich Kurt , Hopt Ulrich Theodor , Obermaier Robert 
Published: October 2008

AbstractIntroduction: Formation of postoperative intra‐abdominal adhesions is a severe problem in surgery. Apart from standard surgical procedures, a variety of different substances is available to prevent adhesions, but no universal method has been developed so far. A membrane consisting of polyvinyl alcohol (PVA) and carboxymethylcellulose (CMC) has been demonstrated to be antiadhesive. Here, the in vitro testing and first in vivo results in a rabbit sidewall model are reported. Materials and Methods: A‐part® membrane contains a PVA/CMC mixture in a thickness of 40 μm. The composition, dissolution, tensile strength, and elasticity were examined to characterize the membrane in vitro. Experiments in vivo were carried out using a ‘rabbit sidewall model’ in which a standardized peritoneal trauma was covered with a 5 × 6 cm A‐part® membrane. Adhesion formation in A‐part®‐treated animals was compared with that in Adept® (15 mL/kg body weight) and untreated controls. Results: An 80/20 PVA/CMC mixture forms a stable, elastic, transparent membrane, which can easily be placed intraoperatively. The dissolution shows a half‐life of about 2 weeks [day 15: (45.1 ± 4.9)% SD], which affords good adhesion protection during the initial critical phase of adhesion formation. In wet conditions, the membrane follows abdominal movements without tearing (tensile strength 5.0 ± 4.2 N/cm SD; elasticity 29.5%). In a rabbit sidewall model, A‐part® membrane significantly reduced adhesion development by (83.1 ± 31.5)% SD compared with the control and the Adept group (p < 0.001). Conclusion: The properties of the A‐part® membrane suggest that it may be useful as an antiadhesive in surgery. A‐part® is effective in invivo testing as determined in a rabbit sidewall model. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Long‐term in vitro stability assessment of polycarbonate urethane micro catheters: Resistance to oxidation and stress cracking
Authors: Chandy Thomas , Van Hee Justin , Nettekoven William , Johnson Jay 
Published: October 2008

AbstractMicro catheter tubes were prepared from poly (carbonate urethane) (PCU, Bionate) and poly (ether urethane) (PEU, Pellethane) and their stability was investigated in vitro under applied strain. The tubes were stretched to an elongation of 200% or 300% and exposed to hydrogen peroxide/cobalt chloride (H2O2/CoCl2) solution for specific periods of time (up to 10 months). The samples were observed for surface degradation via scanning electron microscopy, the bulk erosion via the weight difference, and the changes in molecular weight using gel permeation chromatography. The 200% and 300% strained Pellethane tubes kept in H2O2/CoCl2 solution for 1 month showed substantial cracking of the surface layer with pitting and have degraded completely within 45 to 60 days (from scanning electron microscopy). Bionate tubes treated in similar conditions for a 10‐month period exhibited minute surface erosion in the depth of 0.25–1 μm and showed no evidence of major cracking or pitting. The gel permeation chromatography analysis of 300% strained catheters indicated that the degradation of Bionate tubes was negligible. The 10‐month samples had shown ∼18% reduction in their number average molecular weight (Mn) and about 8% reduction in weight average molecular weight (Mw). The Pellethane studied in similar conditions had indicated ∼72% reduction in Mn and about ∼50% reduction in Mw for 1 month. Overall, the Bionate underwent less degradation and the degradated surface layer was much thinner than Pellethane. These in vitro results are valuable in designing the in vivo studies for using Bionate tube as a long‐term implant. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
The effect of a self‐assembling peptide nanofiber scaffold (peptide) when used as a wound dressing for the treatment of deep second degree burns in rats
Authors: Meng Hui , Chen Liyan , Ye Zhaoyang , Wang Songtao , Zhao Xiaojun 
Published: October 2008

AbstractRADARADARADARADA (RADA16‐I) peptide, consisting of 16 alternating hydrophobic and hydrophilic (also alternating negative and positive charges) amino acids, forms extremely stable β‐pleated sheet structure and then self‐assembles into nanofibers to produce high‐order interwoven nanofiber scaffold hydrogel. To investigate its therapeutic effects, a burn model of partial thickness‐deep dermal injury (the deep second degree burns) was performed at the dorsal skin of female Sprague‐Dawley rats with an electrical scalding machine. The wounds treated with either RADA16‐I or control materials were carefully examined at morphological, histological and cellular levels. We found that RADA16‐I can advance the time of eschar appearance and the time of eschar disappearance both by 3–5 days, and speed up wound contraction by 20–30% compared with contrast groups (chitosan, poly(DL)‐lactic acid (PDLA), collagen I and the blank) without obvious edema. Immunohistochemical studies showed that both FGF and EGF were obviously expressed in nascent tissue such as epidermis and glands when wounds were treated with the RADA16‐I after injury. When peptide stock solution was diluted from 10 to 0.17 mg/mL, atomic force microscopy (AFM) observation showed that the shape of peptide nanofibers changed from the globular‐pieces‐clustered filaments with 4.8 ± 0.38 nm in height, 61.6 ± 6.10 nm in width and 708 ± 80.2 nm in length, to general filaments with 1.4 ± 0.36 nm, 17.5 ± 1.13 nm and 1108 ± 184 nm. The nanofiber surface porosity gradually decreased from 49–70% to 12–28%. These characteristics contribute to wound healing by offering an “ideal dressing” moist healing microenvironment and a nanofiber 3D scaffold. These results suggest that the self‐assembling peptide might be a promising wound dressing with being simple, effective, and affordable. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Control of surface free energy in titanium doped phosphate based glasses by co‐doping with zinc
Authors: Neel Ensanya Ali Abou , O'Dell Luke Austin , Chrzanowski Wojciech , Smith Mark Edmund , Knowles Jonathan Campbell 
Published: October 2008

AbstractTo significantly improve the biocompatibility of titanium doped phosphate based glasses, codoping with zinc has been attempted. This study investigated the effect of doping a quaternary 15Na2O:30CaO:5TiO2:50P2O5 glass with zinc oxide (1, 3, and 5 mol %) on bulk, structural, surface, and biological properties; the results were compared with glasses free from ZnO and/or TiO2. ZnO as adjunct to TiO2 was effective in changing density, interchain bond forces, degradation behavior, and ions released from the degrading glasses. Incorporation of both TiO2 and ZnO in T5Z1, T5Z3, and T5Z5 glasses reduced the level of Zn2+ release by two to three orders of magnitude compared with glasses containing ZnO only (Z5). 31P NMR results for T5Z1, T5Z3, and T5Z5 glasses showed the presence of Q3 species suggesting that the TiO2 is acting as a network former, and the phosphate network becomes slightly more connected with increasing ZnO incorporation. Regardless of their relative lower hydrophilicity and surface reactivity compared with the control glass free from TiO2 and ZnO (T0Z0), these glasses have significantly higher surface reactivity compared with Thermanox®. This has been also reflected in the maintenance of >98% viable Osteoblasts, proliferation rate, and expression level of osteoblastic marker genes in a comparable manner to Thermanox® and T5 glasses, particularly T5Z1 and T5Z3 glasses. However, T0Z0 and Z5 glasses showed significantly reduced viability compared to Thermanox®. Therefore, it can be concluded that ZnO doped titanium phosphate glasses, T5Z1 and T5Z3 in particular, can be promising substrates for bone tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Color Doppler sonography of intrahepatic vascular shunts
Authors: Bertolotto Michele , Martinoli Carlo , Migaleddu Vincenzo , Cernic Stefano , Zappetti Roberta 
Published: October 2008

AbstractPurpose.To illustrate the sonographic and Doppler features of the different types of intrahepatic vascular shunts.Methods.Patients presenting in our department with intrahepatic vascular shunts with healthy livers or with a variety of liver pathologies underwent color Doppler interrogation and spectral analysis.Results.Intrahepatic vascular shunts may involve all liver vessels. Arterioportal and arteriosystemic venous connections can be recognized in normal and cirrhotic livers, following trauma, within tumors, and within nontumoral arteriovenous malformations. Portosystemic intrahepatic venous shunts are categorized into 4 morphologic types. Systemic‐to‐systemic shunts are more often recognized in patients with chronic hepatic venous congestion or with Budd‐Chiari syndrome. Portal‐to‐portal intrahepatic venous shunts are rare, with few cases described.Conclusion.In general, all the liver vessels can be associated with formation of arterioportal, arteriosystemic, and portosystemic venous shunts and, rarely, systemic venous shunts and portal‐to‐portal communications. Sonography allows characterization of the different intrahepatic shunts. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Two‐probe electrical measurements in transmission electron microscopes—Behavioral control of tungsten microwires
Authors: Costa Pedro M.F.J. , Fang Xiaosheng , Wang Shiliang , He Yuehui , Bando Yoshio , Mitome Masanori , Zou Jin , Huang Han , Golberg Dmitri 
Published: October 2008

AbstractTungsten microwires have been manipulated and electrically probed inside a transmission electron microscope. Using Au electrodes, the current–voltage characteristics of the W structures were extracted. These showed highly variable behaviors dependent on various factors, the most important of these being orientation and stiffness of the contact. Careful control of loading force and Au–W contact angle enabled a considerable degree of behavior tailoring from nonlinear to Ohmic responses. Microsc. Res. Tech., 2009. © 2008 Wiley‐Liss, Inc.
Synergistic neuroprotective effect via simian lentiviral vector‐mediated simultaneous gene transfer of human pigment epithelium‐derived factor and human fibroblast growth factor‐2 in rodent models of retinitis pigmentosa
Authors: Miyazaki Masanori , Ikeda Yasuhiro , Yonemitsu Yoshikazu , Goto Yoshinobu , Kohno Ri‐ichiro , Murakami Yusuke , Inoue Makoto , Ueda Yasuji , Hasegawa Mamoru , Tobimatsu Shozo , Sueishi Katsuo , Ishibashi Tatsuro 
Published: October 2008

AbstractBackgroundWe previously demonstrated that a new lentiviral vector derived from nonpathogenic simian immunodeficiency virus (SIVagm) was efficient and safe for long‐lasting retinal gene transfer, and that it provided the significant therapeutic effect of expressing human pigment epithelium‐derived factor (hPEDF) in Royal College of Surgeons (RCS) rats. In the present study, to obtain a more pronounced outcome, we assessed the potential synergistic effect of the simultaneous gene transfer of hPEDF and human fibroblast growth factor‐2 (hFGF‐2) by improved third‐generation SIV on RCS rats and retinal degeneration slow (rds) mice, because the former targets the primary neurons, including photoreceptor cells (PCs), whereas the latter is effective for targeting secondary neural cells, including Muller cells.MethodsVector solution (SIV‐hPEDF, SIV‐hFGF‐2, a 1 : 1 mixture of SIV‐hPEDF and SIV‐hFGF‐2, or SIV‐enhanced green fluorescent protein) was injected into the peripheral subretinal space of 3‐week‐old RCS rats or rds mice. Histopathological and electroretinographic assessments were made at several points after gene transfer.ResultsAdministration of SIV‐hPEDF or SIV‐hFGF‐2 significantly delayed the histological PC degeneration and electrical deficit in RCS rats, and these delays were synergistically and significantly pronounced by SIV‐hPEDF + SIV‐hFGF‐2 (1 : 1 mixture). In rds mice, functional therapeutic effects were observed even by SIV‐PEDF, or SIV‐FGF‐2 alone and, moreover, both SIV‐PEDF and SIV‐FGF‐2 showed higher therapeutic effects.ConclusionsThese synergistic rescues of retinitis pigmentosa (RP) model animals are the ‘proof concept’ that the ‘dual’ expression of hPEDF and hFGF‐2 dramatically improved therapeutic efficacy by keeping lower titers. This strategy may contribute to safer and more effective gene therapy for RP. Copyright © 2008 John Wiley & Sons, Ltd.
Contractors and connectors of graph algebras
Authors: Lovász László , Szegedy Balázs 
Published: October 2008

AbstractWe study generalizations of the “contraction‐deletion” relation of the Tutte polynomial, and other similar simple operations, to other graph parameters. The question can be set in the framework of graph algebras introduced by Freedman at al [Reflection positivity, rank connectivity, and homomorphisms of graphs, J. Amer. Math. Soc. 20 (2007), 37–51.] Graph algebras are defined by a graph parameter, and they were introduced in order to study and characterize homomorphism functions. We prove that for homomorphism functions, these graph algebras have special elements called “contractors” and “connectors”. This gives a new characterization of homomorphism functions. © 2008 Wiley Periodicals, Inc. J Graph Theory 60: 11–30, 2009
Small‐scale farmer participation in new agri‐food supply chains: Case of the supermarket supply chain for fruit and vegetables in Honduras
Authors: Blandon Jose , Henson Spencer , Cranfield John 
Published: October 2008

AbstractThis paper explores the role of transaction costs and collective action in shaping small‐scale farmer participation in the fresh fruit and vegetable (FFV) supply chain to supermarkets (SSC) in Honduras. Transaction costs and collective action are found to be significant in determining farmer participation in the SSC. Contrary to the findings of other studies, human capital and farm characteristic variables are not significant, suggesting that small‐scale farmers can be included in new supply chains under certain conditions, especially if incentives to farmers, trust‐based relationships between buyers and sellers, risk reduction practices and new forms of collective action are put in place. Copyright © 2008 John Wiley & Sons, Ltd.
How does economic empowerment affect women's risk of intimate partner violence in low and middle income countries? A systematic review of published evidence
Authors: Vyas Seema , Watts Charlotte 
Published: October 2008

AbstractObjectivesTo identify whether individual and household economic empowerment is associated with lower intimate partner violence in low and middle income country settings.MethodsSystematic PubMed and internet searches.ResultsPublished data from 41 sites were reviewed. Household assets and women's higher education were generally protective. Evidence about women's involvement in income generation and experience of past year violence was mixed, with five finding a protective association and six documenting a risk association.ConclusionAt an individual and household level, economic development and poverty reduction may have protective impacts on IPV. Context specific factors influence whether financial autonomy is protective or associated with increased risk. Copyright © 2008 John Wiley & Sons, Ltd.This article was published online on 6 October 2008. Errors were subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected [17 April 2009].
Why do the poor pay more? Exploring the poverty penalty concept
Authors: Mendoza Ronald U. 
Published: October 2008

AbstractThe poverty penalty refers to the relatively higher cost shouldered by the poor, when compared to the non‐poor, in their participation in certain markets. By trying to further develop this concept, this paper clarifies some of the subtle and more direct ways through which the poor could be marginalised in the market system. A brief review of the business and economics literature suggests that there are different possible causes behind various forms of the poverty penalty, and hence distinct ways to address them, depending on its form, the nature of the market under analysis, the specific country context, the characteristics of the poor themselves and the prevalence of market failures among other factors. Copyright © 2008 John Wiley & Sons, Ltd.
Oxidoreductase activities of polyclonal IgGs from the sera of Wistar rats are better activated by combinations of different metal ions
Authors: Tolmacheva Anna S. , Zaksas Nataliya P. , Buneva Valentina N. , Vasilenko Nataliya L. , Nevinsky Georgy A. 
Published: October 2008

AbstractIt was shown that IgGs purified from the sera of healthy Wistar rats contain several different bound Me2+ ions and oxidize 3,3′‐diaminobenzidine through a H2O2‐dependent peroxidase and H2O2‐independent oxidoreductase activity. IgGs have lost these activities after removing the internal metal ions by dialysis against EDTA. External Cu2+ or Fe2+ activated significantly both activities of non‐dialysed IgGs containing different internal metals (Fe ≥ Pb ≥ Zn ≥ Cu ≥ Al ≥ Ca ≥ Ni ≥ Mn > Co ≥ Mg) showing pronounced biphasic dependencies corresponding to ∼0.1–2 and ∼2–5 mM of Me2+, while the curves for Mn2+ were nearly linear. Cu2+ alone significantly stimulated both the peroxidase and oxidoreductase activities of dialysed IgGs only at high concentration (≥ 2 mM), while Mn2+ weakly activated peroxidase activity at concentration >3 mM but was active in the oxidoreductase oxidation at a low concentration (<1 mM). Fe2+‐dependent peroxidase activity of dialysed IgGs was observed at 0.1–5 mM, but Fe2+ was completely inactive in the oxidoreductase reaction. Mg2+, Ca2+, Zn2+, Al2+ and especially Co2+ and Ni2+ were not able to activate dialysed IgGs, but slightly activated non‐dialysed IgGs. The use of the combinations of Cu2+ + Mn2+, Cu2+ + Zn2+, Fe2+ + Mn2+, Fe2+ + Zn2+ led to a conversion of the biphasic curves to hyperbolic ones and in parallel to a significant increase in the activity as compared with Cu2+, Fe2+ or Mn2+ ions taken separately; the rates of the oxidation reactions, catalysed by non‐dialysed and dialysed IgGs, became comparable. Mg2+, Co2+ and Ni2+ markedly activated the Cu2+‐dependent oxidation reactions catalysed by dialysed IgGs, while Ca2+ inhibited these reactions. A possible role of the second metal in the oxidation reactions is discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Protein profile and malt activity during sorghum germination
Authors: Correia Isabel , Nunes Alexandra , Barros António S , Delgadillo Ivonne 
Published: October 2008

AbstractBACKGROUND: The effect of germination time on major sorghum macromolecules was followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy. Sorghum flour was also incubated with sorghum malt to evaluate amylase and protease activities.RESULTS: The SDS‐PAGE results showed that levels of high‐molecular‐weight aggregates, β monomer and γ and α monomers increased by 120.5, 20.3 and 12.7% respectively during the first few days of germination. This behaviour shows the enhancement of prolamin extractability and concentration in sorghum as a result of starch degradation. After the third day, proteins suffered degradation by intrinsic proteases. FTIR spectroscopy showed a gradual decrease in lipid and protein levels and starch structural changes during the germination period. These modifications are due to intrinsic lipases, proteases and amylases. Sorghum flour was incubated with different malt samples resulting from 0–7 days of germination. It was found that a 5 day malt led to a sixfold increase in carbohydrate digestibility and a fourfold increase in free amino acid content.CONCLUSION: A 5 day sorghum malt is the best inoculum for porridge preparation, representing an inexpensive, effortless and culturally acceptable way to prepare weaning foods at domestic and industrial levels. Copyright © 2008 Society of Chemical Industry