bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐strength poly(para‐phenylene) as an orthopedic biomaterial
Authors: Frick Carl P. , DiRienzo Amy L. , Hoyt Anthony J. , Safranski David L. , Saed Mohand , Losty Eric J. , Yakacki Christopher M. 
Published: October 2013

AbstractPoly(para‐phenylene) (PPP) exhibits exceptional mechanical strength, stiffness, toughness, and chemical inertness, although it is not currently used in any biomedical applications. The purpose of this study is to serve as a preliminary investigation into the potential of PPP as a biomaterial in orthopedic load‐bearing applications. Nuclear magnetic resonance (NMR) analysis confirmed a polymer structure composed of an aromatic backbone and side groups. Tensile PPP specimens along with samples from several other polymers often used for orthopedic applications were elongated to failure after being soaked in phosphate buffered saline (PBS) for 1 h, 1 day, 1 week, 2 weeks, 1 month, and more than 1 year. Results showed that PBS absorption of the PPP plateaued at 1 week at values of ∼0.7 wt % and remained within one standard deviation when soaked for over 1 year. PBS absorption did not affect elastic modulus (5.0 GPa), yield strength (141 MPa), fracture strength (120 MPa) and strain‐to‐failure (17%) more than one standard deviation. Zero‐to‐tension fatigue testing established an endurance limit of approximately 35 MPa, which was relatively insensitive to frequency (1–10 Hz). Eagle's minimum essential medium (MEM) elution assay with fibroblasts confirmed that the PPP was noncytotoxic. Relative to other polymers used for load‐bearing biomedical applications, PPP displays promising mechanical properties that remain stable in aqueous solution. Lastly, prototype PPP and polyetheretherketone (PEEK) bone plates were manufactured and tested, with the PPP plate showing a 38% higher maximum tensile load before failure. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3122–3129, 2014.
Undifferentiated human adipose‐derived stromal/stem cells loaded onto wet‐spun starch–polycaprolactone scaffolds enhance bone regeneration: Nude mice calvarial defect in vivo study
Authors: Carvalho Pedro P. , Leonor Isabel B. , Smith Brenda J. , Dias Isabel R. , Reis Rui L. , Gimble Jeffrey M. , Gomes Manuela E. 
Published: October 2013

AbstractThe repair of large bony defects remains challenging in the clinical setting. Human adipose‐derived stromal/stem cells (hASCs) have been reported to differentiate along different cell lineages, including the osteogenic. The objective of the present study was to assess the bone regeneration potential of undifferentiated hASCs loaded in starch‐polycaprolactone (SPCL) scaffolds, in a critical‐sized nude mice calvarial defect. Human ASCs were isolated from lipoaspirate of five female donors, cryopreserved, and pooled together. Critical‐sized (4 mm) calvarial defects were created in the parietal bone of adult male nude mice. Defects were either left empty, treated with an SPCL scaffold alone, or SPCL scaffold with human ASCs. Histological analysis and Micro‐CT imaging of the retrieved implants were performed. Improved new bone deposition and osseointegration was observed in SPCL loaded with hASC engrafted calvarial defects as compared to control groups that showed little healing. Nondifferentiated human ASCs enhance ossification of nonhealing nude mice calvarial defects, and wet‐spun SPCL confirmed its suitability for bone tissue engineering. This study supports the potential translation for ASC use in the treatment of human skeletal defects. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3102–3111, 2014.
Designing colon‐specific delivery systems for anticancer drug‐loaded nanoparticles: An evaluation of alginate carriers
Authors: Ma Yiming , Coombes Allan G. A. 
Published: October 2013

AbstractIncorporation of drug‐loaded nanoparticles (NPs) in colon‐specific delivery systems shows potential for raising local drug concentrations, tumor targeting and improving chemotherapy. Alginate microcapsules (15–80 µm diameter) containing insoluble Eudragit® RS NPs as models were characterized precisely in terms of NP loading and release kinetics. High NP loading (22%, w/w of the dried microcapsules) combined with negligible release in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) suggested that high concentrations of NPs could be transported to the colon. However, NP aggregation was confirmed at extremely low concentration (0.0003%, w/v) in alginate solution (0.007%, w/v) and after release from alginate microcapsules. Indomethacin, a model anticolorectal cancer drug, was encapsulated in pH‐responsive Eudragit® S100 NPs (116 nm, 5%, w/w drug loading) using the nanoprecipitation method. Approximately 90% of the drug load was released from the NPs in SGF and SIF before transfer to simulated colon fluid (SCF). However, incorporation of NPs in 2 mm alginate pellets resulted in a significantly higher fraction of the drug load (around 60%) being available for release in SCF. Delivery of isolated NPs to the colon for interaction with and uptake by cancer cells requires elimination of NP‐excipient interactions that promote NP aggregation. NP‐loaded alginate carriers, meanwhile, offer a promising strategy for delivery of anticancer drugs to tumor sites in the colon and reducing systemic side effects. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3167–3176, 2014.
Bonding between oxide ceramics and adhesive cement systems: A systematic review
Authors: Papia Evaggelia , Larsson Christel , du Toit Madeleine , von Steyern Per Vult 
Published: October 2013

AbstractThe following aims were set for this systematic literature review: (a) to make an inventory of existing methods to achieve bondable surfaces on oxide ceramics and (b) to evaluate which methods might provide sufficient bond strength. Current literature of in vitro studies regarding bond strength achieved using different surface treatments on oxide ceramics in combination with adhesive cement systems was selected from PubMed and systematically analyzed and completed with reference tracking. The total number of publications included for aim a was 127 studies, 23 of which were used for aim b. The surface treatments are divided into seven main groups: as‐produced, grinding/polishing, airborne particle abrasion, surface coating, laser treatment, acid treatment, and primer treatment. There are large variations, making comparison of the studies difficult. An as‐produced surface of oxide ceramic needs to be surface treated to achieve durable bond strength. Abrasive surface treatment and/or silica‐coating treatment with the use of primer treatment can provide sufficient bond strength for bonding oxide ceramics. This conclusion, however, needs to be confirmed by clinical studies. There is no universal surface treatment. Consideration should be given to the specific materials to be cemented and to the adhesive cement system to be used. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 395–413, 2014.
The development of an in vitro test method for predicting the abrasion resistance of textile and metal components of endovascular stent grafts
Authors: Yao Tong , Choules Brian D. , Rust Jon P. , King Martin W. 
Published: October 2013

ABSTRACTImplantable endovascular stent grafts have become a frequent option for the treatment of abdominal and thoracic aneurysms. Given that such devices are permanent implants, the question of long‐term biostability needs to be addressed. This article describes the development of an in vitro stent graft abrasion test method between the graft fabric and metal stent of an endovascular device. Three endpoints were established to determine the abrasion resistance between the fabric and stent surfaces after a predetermined number of abrasion cycles. During initial testing, two types of graft fabric materials, multifilament woven polyester fabric and monofilament woven polyester fabric, and two types of stent materials, laser cut nitinol stents and regular nitinol stent wire, were evaluated under dry and wet conditions. The results have shown that this test method is viable for testing the relative abrasion resistance of the components of endovascular stent grafts. The abrasion resistance of both fabrics was lower in a wet environment compared to being tested dry. Additionally, the multifilament polyester fabric had better abrasion resistance than the monofilament polyester fabric. The laser cut nitinol stent was more aggressive in creating holes and breaking yarns, while the regular nitinol stent wire caused a greater loss in fabric strength. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 488–499, 2014.
Tailoring of antibacterial Ag nanostructures on TiO2 nanotube layers by magnetron sputtering
Authors: Uhm Soo‐Hyuk , Song Doo‐Hoon , Kwon Jae‐Sung , Lee Sang‐Bae , Han Jeon‐Geon , Kim Kyoung‐Nam 
Published: October 2013

AbstractTo reduce the incidence of postsurgical bacterial infection that may cause implantation failure at the implant–bone interface, surface treatment of titanium implants with antibiotic materials such as silver (Ag) has been proposed. The purpose of this work was to create TiO2 nanotubes using plasma electrolytic oxidation (PEO), followed by formation of an antibacterial Ag nanostructure coating on the TiO2 nanotube layer using a magnetron sputtering system. PEO was performed on commercially pure Ti sheets. The Ag nanostructure was added onto the resulting TiO2 nanotube using magnetron sputtering at varying deposition rates. Field emission scanning electron microscopy and transmission electron microscopy were used to characterize the surface, and Ag content on the TiO2 nanotube layer was analyzed by X‐ray diffraction and X‐ray photoelectron spectroscopy. Scanning probe microscopy for surface roughness and contact angle measurement were used to indirectly confirm enhanced TiO2 nanotube hydrophilicity. Antibacterial activity of Ag ions in solution was determined by inductively coupled plasma mass spectrometry and antibacterial testing against Staphylococcus aureus (S. aureus). In vitro, TiO2 nanotubes coated with sputtered Ag resulted in significantly reduced S. aureus. Cell viability assays showed no toxicity for the lowest sputtering time group in the osteoblastic cell line MC3T3‐E1. These results suggest that a multinanostructured layer with a biocompatible TiO2 nanotube and antimicrobial Ag coating is a promising biomaterial that can be tailored with magnetron sputtering for optimal performance. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 592–603, 2014.
Vitamin D3 Dose Requirement to Raise 25-Hydroxyvitamin D to Desirable Levels in Adolescents: Results from a Randomized Controlled Trial
Authors: Al-Shaar Laila , Mneimneh Rania , Mona Nabulsi  , Maalouf Joyce , Fuleihan Ghada El-Hajj 
Published: October 2013

ABSTRACT

Several organizations issued recommendations on desirable serum 25-hydroxy vitamin D [25(OH)D] levels and doses of vitamin D needed to achieve them. Trials allowing the formulation of evidence-based recommendations in adolescents are scarce. We investigated the ability of two doses of vitamin D3 in achieving recommended vitamin D levels in this age group. Post hoc analyses on data from a 1-year double-blind trial that randomized 336 Lebanese adolescents, aged 13 ± 2 years, to placebo, vitamin D3 at 200 IU/day (low dose), or 2000 IU/day (high dose). Serum 25(OH)D level and proportions of children achieving levels ≥20 ng/mL and 30 ng/mL were determined. At baseline, mean 25(OH)D was 15 ± 7 ng/mL, 16.4 ± 7 ng/mL in boys, and 14 ± 8 ng/mL in girls, p = 0.003, with a level ≥20 ng/mL in 18% and ≥30 ng/mL in 5% of subjects. At 1 year, mean levels were 18.6 ± 6.6 ng/mL in the low-dose group, 17.1 ± 6 ng/mL in girls, and 20.2 ± 7 ng/mL in boys, p = 0.01, and 36.3 ± 22.3 ng/mL in the high-dose group, with no sex differences. 25(OH)D increased to ≥20 ng/mL in 34% of children in the low-dose and 96% in the high-dose group, being higher in boys in the low-dose arm only; it remained ≥30 ng/mL in 4% of children in the low-dose arm but increased to 64% in the high-dose arm. Baseline 25(OH)D level, body mass index (BMI), and vitamin D dose assigned were the most significant predictors for reaching a 25(OH)D level ≥20 ng/mL and 30 ng/mL. A daily dose of 2000 IU raised 25(OH)D level ≥20 ng/mL in 96% of adolescents (98% boys versus 93% girls). Dose-response studies are needed to determine in a definitive manner the daily allowance of vitamin D for Middle Eastern adolescents with a similar profile. © 2014 American Society for Bone and Mineral Research.
Nanotopographical Effects on Mesenchymal Stem Cell Morphology and Phenotype
Authors: Tsimbouri Penelope , Gadegaard Nikolaj , Burgess Karl , White Kate , Reynolds Paul , Herzyk Pawel , Oreffo Richard , Dalby Matthew J. 
Published: October 2013

AbstractThere is a rapidly growing body of literature on the effects of topography and critically, nanotopography on cell adhesion, apoptosis and differentiation. Understanding the effects of nanotopography on cell adhesion and morphology and the consequences of cell shape changes in the nucleus, and consequently, gene expression offers new approaches to the elucidation and potential control of stem cell differentiation. In the current study we have used molecular approaches in combination with immunohistology and transcript analysis to understand the role of nanotopography on mesenchymal stem cell morphology and phenotype. Results demonstrate large changes in cell adhesion, nucleus and lamin morphologies in response to the different nanotopographies. Furthermore, these changes relate to alterations in packing of chromosome territories within the interphase nucleus. This, in turn, leads to changes in transcription factor activity and functional (phenotypical) signalling including cell metabolism. Nanotopography provides a useful, non‐invasive tool for studying cellular mechanotransduction, gene and protein expression patterns, through effects on cell morphology. The different nanotopographies examined, result in different morphological changes in the cyto‐ and nucleo‐skeleton. We propose that both indirect (biochemical) and direct (mechanical) signalling are important in these early stages of regulating stem cell fate as a consequence of altered metabolic changes and altered phenotype. The current studies provide new insight on cell–surface interactions and enhance our understanding of the modulation of stem cell differentiation with significant potential application in regenerative medicine. J. Cell. Biochem. 115: 380–390, 2014. © 2013 The Authors. Journal of Cellular Biochemistry published by Wiley Periodicals, Inc.
Specific In Situ Detection of Murine Indoleamine 2, 3‐Dioxygenase
Authors: Thomas Sunil , DuHadaway James , Prendergast George C. , Laury‐Kleintop Lisa 
Published: October 2013

ABSTRACTIndoleamine 2,3‐dioxygenase‐1 (IDO1) catabolizes the essential amino acid tryptophan, acting as a modifier of inflammation and immune tolerance. Recent work has implicated IDO1 in many human diseases, including in cancer, chronic infection, autoimmune disorders, and neurodegenerative disease, stimulating a major surge in preclinical and clinical studies of its pathogenic functions. In the mouse, IDO1 is expressed widely but in situ detection of the enzyme in murine tissues has been unreliable due to the lack of specific antibodies that do not also react with tissues from animals that are genetically deficient in IDO1. Such probes are crucial to establish cellular mechanisms since IDO1 appears to act in different cell types depending on disease context, but reliable probes have been elusive in the field. In this report, we address this issue with the development of IDO1 monoclonal antibody 4B7 which specifically recognizes the murine enzyme in tissue sections, offering a reliable tool for immunohistology in preclinical disease models. J. Cell. Biochem. 115: 391–396, 2014. © 2013 Wiley Periodicals, Inc.
Expression, Functionality, and Localization of Apurinic/Apyrimidinic Endonucleases in Replicative and Non‐Replicative Forms of Trypanosoma cruzi
Authors: Sepúlveda S. , Valenzuela L. , Ponce I. , Sierra S. , Bahamondes P. , Ramirez S. , Rojas V. , Kemmerling U. , Galanti N. , Cabrera G. 
Published: October 2013

ABSTRACTTrypanosoma cruzi is the etiological agent of Chagas disease. The parasite has to overcome oxidative damage by ROS/RNS all along its life cycle to survive and to establish a chronic infection. We propose that T. cruzi is able to survive, among other mechanisms of detoxification, by repair of its damaged DNA through activation of the DNA base excision repair (BER) pathway. BER is highly conserved in eukaryotes with apurinic/apirimidinic endonucleases (APEs) playing a fundamental role. Previous results showed that T. cruzi exposed to hydrogen peroxide and peroxinitrite significantly decreases its viability when co‐incubated with methoxyamine, an AP endonuclease inhibitor. In this work the localization, expression and functionality of two T. cruzi APEs (TcAP1, Homo sapiens APE1 orthologous and TcAP2, orthologous to Homo sapiens APE2 and to Schizosaccaromyces pombe Apn2p) were determined. These enzymes are present and active in the two replicative parasite forms (epimastigotes and amastigotes) as well as in the non‐replicative, infective trypomastigotes. TcAP1 and TcAP2 are located in the nucleus of epimastigotes and their expression is constitutive. Epimastigote AP endonucleases as well as recombinant TcAP1 and TcAP2 are inhibited by methoxyamine. Overexpression of TcAP1 increases epimastigotes viability when they are exposed to acute ROS/RNS attack. This protective effect is more evident when parasites are submitted to persistent ROS/RNS exposition, mimicking nature conditions. Our results confirm that the BER pathway is involved in T. cruzi resistance to DNA oxidative damage and points to the participation of DNA AP endonucleases in parasite survival. J. Cell. Biochem. 115: 397–409, 2014. © 2013 Wiley Periodicals, Inc.
The Many Faces of Asthma in Obesity
Authors: Sideleva O. , Dixon A.E. 
Published: October 2013

ABSTRACTObesity is a major risk factor for the development of asthma, and causes severe, uncontrolled disease that responds poorly to therapy. The obese state alters early onset allergic asthma, and leads to the development of a novel form of late onset asthma secondary to obesity. The presentation of early onset allergic asthma is altered through effects on immune function. Factors such as mechanical loading, effects of adipokines on airways, altered diet, insulin resistance and altered metabolism of nitric oxide likely all contribute to increased airway reactivity in obesity, causing late onset asthma in obesity. Obesity also alters responses to environmental factors such as ozone and particulate matter. Focused studies to understand the importance of these factors in the pathogenesis of airway disease in obesity will be essential to develop therapies to intervene in this new epidemic of airway disease. J. Cell. Biochem. 115: 421–426, 2014. © 2013 Wiley Periodicals, Inc.
Nuclear Structures Surrounding Internal Lamin Invaginations
Authors: Legartová Soňa , Stixová Lenka , Laur Oskar , Kozubek Stanislav , Sehnalová Petra , Bártová Eva 
Published: October 2013

ABSTRACTA‐ and C‐type lamins are intermediate filament proteins responsible for the maintenance of nuclear shape and most likely nuclear architecture. Here, we propose that pronounced invaginations of A/C‐type lamins into the nuclear interior represent channels for the transport of regulatory molecules to and from nuclear and nucleolar regions. Using fluorescent protein technology and immunofluorescence, we show that A‐type lamin channels interact with several nuclear components, including fibrillarin‐ and UBF‐positive regions of nucleoli, foci of heterochromatin protein 1 β, polycomb group bodies, and genomic regions associated with DNA repair. Similar associations were observed between A/C‐type lamin channels and nuclear pores, lamin‐associated protein LAP2α, and promyelocytic leukemia nuclear bodies. Interestingly, regions with high levels of A/C‐type lamins had low levels of B‐type lamins, and vice versa. These characteristics were observed in primary and immortalized mouse embryonic fibroblasts as well as human and mouse embryonic stem cell colonies exhibiting stem cell‐specific lamin positivity. Our findings indicate that internal channels formed by nuclear lamins likely contribute to normal cellular processes through association with various nuclear and nucleolar structures. J. Cell. Biochem. 115: 476–487, 2014. © 2013 Wiley Periodicals, Inc.
Transplantation of iPSc Ameliorates Neural Remodeling and Reduces Ventricular Arrhythmias in a Post‐Infarcted Swine Model
Authors: Zhang Fengxiang , Song Guixian , Li Xiaorong , Gu Weijuan , Shen Yahui , Chen Minglong , Yang Bing , Qian Lingmei , Cao Kejiang 
Published: October 2013

ABSTRACTNeural remodeling after myocardial infarction (MI) may cause malignant ventricular arrhythmia, which is the main cause of sudden cardiac death following MI. Herein, we aimed to examine whether induced pluripotent stem cells (iPSc) transplantation can ameliorate neural remodeling and reduce ventricular arrhythmias (VA) in a post‐infarcted swine model. Left anterior descending coronary arteries were balloon‐occluded to generate MI. Animals were then divided into Sham, PBS control, and iPS groups. Dynamic electrocardiography programmed electric stimulation were performed to evaluate VA. The spatial distribution of vascularization, Cx43 and autonomic nerve regeneration were evaluated by immunofluorescence staining. Associated protein expression was detected by Western blotting. Likewise, we measured the enzymatic activities of superoxide dismutase and content of malondialdehyde. Six weeks later, the number of blood vessels increased significantly in the iPSc group. The expression of vascular endothelial growth factor and connexin 43 in the iPS group was significantly higher than the PBS group; however, the levels of nerve growth factor and tyrosine hydroxylase were lower. The oxidative stress was ameliorated by iPSc transplantation. Moreover, the number of sympathetic nerves in the iPSc group was reduced, while the parasympathetic nerve fibers had no obvious change. The transplantation of iPSc also significantly decreased the low‐/high‐frequency ratio and arrhythmia score of programmed electric stimulation‐induced VA. In conclusion, iPSc intramyocardial transplantation reduces vulnerability to VAs, and the mechanism was related to the remodeling amelioration of autonomic nerves and gap junctions. Moreover, possible mechanisms of iPSc transplantation in improving neural remodeling may be related to attenuated oxidative stress and inflammatory response. J. Cell. Biochem. 115: 531–539, 2014. © 2013 Wiley Periodicals, Inc.