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Sample records for bone potential applications

  1. Stem cell technology for bone regeneration: current status and potential applications

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    Asatrian G

    2015-02-01

    Full Text Available Greg Asatrian,1 Dalton Pham,1,2 Winters R Hardy,3 Aaron W James,1–3 Bruno Peault3,4 1Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, 2Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, 3UCLA/Orthopaedic Hospital Department of Orthopaedic Surgery and the Orthopaedic Hospital Research Center, Los Angeles, CA, USA; 4Medical Research Council Centre for Regenerative Medicine, Edinburgh, Scotland, UK Abstract: Continued improvements in the understanding and application of mesenchymal stem cells (MSC have revolutionized tissue engineering. This is particularly true within the field of skeletal regenerative medicine. However, much remains unknown regarding the native origins of MSC, the relative advantages of different MSC populations for bone regeneration, and even the biologic safety of such unpurified, grossly characterized cells. This review will first summarize the initial discovery of MSC, as well as the current and future applications of MSC in bone tissue engineering. Next, the relative advantages and disadvantages of MSC isolated from distinct tissue origins are debated, including the MSC from adipose, bone marrow, and dental pulp, among others. The perivascular origin of MSC is next discussed. Finally, we briefly comment on pluripotent stem cell populations and their possible application in bone tissue engineering. While continually expanding, the field of MSC-based bone tissue engineering and regeneration shows potential to become a clinical reality in the not-so-distant future.Keywords: mesenchymal stem cell, pericyte, bone tissue engineering, MSC, ASC, DMSC

  2. Preclinical investigation of an innovative magnesium-based bone graft substitute for potential orthopaedic applications

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    Chen Liu

    2014-07-01

    Full Text Available Degradable or corrosive biometal is an attractive research and development (R&D area in clinical orthopaedics. This study was designed to investigate biomechanical and biological properties of magnesium (Mg and strontium (Sr with a focus on Mg-based metals, including pure Mg and Mg–xwt% Sr (x = 0.25, x = 1.0, x = 1.5, x = 2.5 alloys, as potential bone graft substitutes in respect to their mechanical strength, corrosion resistance, and cytocompatibility for further optimization and establishing indications for relevant in vivo applications. Our data showed that the tensile and compressive strength increased with addition of Sr because of the Mg17Sr2 precipitation strengthen. Compared with commercially used bone graft substitutes, the mechanical properties of Mg–Sr alloys were close to those of cortical bone, and the compressive strength could reach 300 MPa, suggesting its potential application for load-bearing bone as bone defect filler. The corrosion rates of Mg–xwt% Sr alloys were controlled in the range of 0.05–0.07 mm/y, indicating feasibility of bone grafting and the in situ bone repair process. Moreover, Mg–Sr alloys also exhibit good cytocompatibility and antibacterial properties. Our innovation presented in this work supported in vivo clinical indication-based assessment of biodegradable Mg-based metals that could be potential candidates for bone graft substitutes for future orthopaedic applications.

  3. Nano-hydroxyapatite/β-CD/chitosan nanocomposite for potential applications in bone tissue engineering.

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    Shakir, Mohammad; Jolly, Reshma; Khan, Mohd Shoeb; Rauf, Ahmar; Kazmi, Shadab

    2016-12-01

    Herein, we report the synthesis of a novel tri-component nanocomposite system incorporating β-cyclodextrin (β-CD) with nano-hydroxyapatite (n-HA) and chitosan (CS), (n-HA/β-CD/CS) at three different temperatures via co-precipitation method. The chemical interactions and surface morphology have been evaluated by TEM, SEM and AFM techniques revealing the agglomerated nanoparticles in CS/n-HA-HA binary system whereas the ternary systems produced needle shaped nanoparticles dispersed homogeneously at low temperature with more porous and rougher surface. The addition of β-CD in CS/n-HA at low temperature decreased the particle size and raised the thermal stability as compared to CS/n-HA. The comparative hemolytic, protein adsorption and platelet adhesion studies confirmed the better hemocompatibility of n-HA/β-CD/CS-(RT,HT,LT) nanocomposites relative to CS/n-HA. The cell viability has been evaluated in vitro using MG-63 cell line which revealed superior non toxicity of n-HA/β-CD/CS-LT nanocomposite in comparison to n-HA/β-CD/CS-(RT,HT) and CS/n-HA nanocomposites. Thus it may be concluded that the orchestrated organic/inorganic n-HA/β-CD/CS-(RT,HT,LT) nanocomposites exhibited relatively higher cell viability of human osteoblast cells, stimulated greater osteogenesis, controlled biodegradation, enhanced antibacterial activity with excellent in-vitro biomineralization and remarkable mechanical parameters as compared to CS/n-HA nanocomposite and thus may provide opportunities for potential use as an alternative biomaterial for Bone tissue engineering applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Poly aspartic acid peptide-linked PLGA based nanoscale particles: potential for bone-targeting drug delivery applications.

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    Jiang, Tao; Yu, Xiaohua; Carbone, Erica J; Nelson, Clarke; Kan, Ho Man; Lo, Kevin W-H

    2014-11-20

    potential for bone disease therapy in clinical applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Adjustment methodology for preliminary study on the distribution of bone tissue boron. Potential therapeutic applications

    International Nuclear Information System (INIS)

    Brandizzi, D; Dagrosa, A; Carpano, M.; Olivera, M. S.; Nievas, S; Cabrini, R.L.

    2013-01-01

    Boron is an element that has an affinity for bone tissue and represents a considered element in bone health . Other boron compounds are used in the Boron Neutron Capture Therapy (BNCT ) in the form of sodium borocaptate (BSH ) and borono phenylalanine (BPA). The results of clinical trials up to date are encouraging but not conclusive . At an experimental level , some groups have applied BNCT in osteosarcomas . We present preliminary methodological adjustments for the presence of boron in bone. (author)

  6. Review - bioactive glass implants for potential application in structural bone repair

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    Rahaman Mohamed N.

    2017-09-01

    Full Text Available Bioactive glass particles andweak scaffolds have been used to heal small contained bone defects but an unmet challenge is the development of bioactive glass implants with the requisite mechanical reliability and in vivo performance to heal structural bone defects. Inadequate mechanical strength and a brittle mechanical response have been key concerns in the use of bioactive glass scaffolds in structural bone repair. Recent research has shown the capacity to create strong porous bioactive glass scaffolds and the ability of these scaffolds to heal segmental bone defects in small and large rodents at a rate comparable to autogenous bone grafts. Loading these strong porous scaffolds with bone morphogenetic protein-2 can significantly enhance their ability to regenerate bone. Recentwork has also shown that coating the external surface of strong porous scaffolds with an adherent biodegradable polymer can dramatically improve their load-bearing capacity in flexural loading and their work of fracture (a measure of toughness. These tough and strong bioactive glass-polymer composites with an internal architecture conducive to bone infiltration could provide optimal synthetic implants for structural bone repair.

  7. Development of Novel Biocomposite Scaffold of Chitosan-Gelatin/Nanohydroxyapatite for Potential Bone Tissue Engineering Applications.

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    Dan, Yang; Liu, Ouyang; Liu, Yong; Zhang, Yuan-Yuan; Li, Shuai; Feng, Xiao-Bo; Shao, Zeng-Wu; Yang, Cao; Yang, Shu-Hua; Hong, Ji-Bo

    2016-12-01

    In this study, a three-dimensional chitosan-gelatin/nanohydroxyapatite (ChG/nHaP) scaffold was successfully fabricated and characterized in terms of swelling, degradation, cell proliferation, cell attachment, and mineralization characterizations. The ChG/nHaP scaffold was fabricated with a mean pore size of 100-180 μm. Our results showed that the physicochemical and biological properties of the scaffolds were affected by the presence of HaP. The swelling and degradation characteristics of the ChG scaffold were remarkably decreased by the addition of HaP. On the other hand, the presence of HaP remarkably improved the MC3T3-E1 cell attachment and cell growth in the scaffold membrane. The biocompatible nature of the ChG/nHaP scaffold leads to the development of finely scaled mineral deposits on the scaffold membrane. Thus, HaP played an important role in improving the biological performance of the scaffold. Therefore, the ChG/nHaP scaffold could be applied as a suitable material for bone tissue engineering applications.

  8. Hierarchical Structure of Articular Bone-Cartilage Interface and Its Potential Application for Osteochondral Tissue Engineering

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    Bian, Weiguo; Qin, Lian; Li, Dichen; Wang, Jin; Jin, Zhongmin

    2010-09-01

    The artificial biodegradable osteochondral construct is one of mostly promising lifetime substitute in the joint replacement. And the complex hierarchical structure of natural joint is important in developing the osteochondral construct. However, the architecture features of the interface between cartilage and bone, in particular those at the micro-and nano-structural level, remain poorly understood. This paper investigates these structural data of the cartilage-bone interface by micro computerized tomography (μCT) and Scanning Electron Microscope (SEM). The result of μCT shows that important bone parameters and the density of articular cartilage are all related to the position in the hierarchical structure. The conjunctions of bone and cartilage were defined by SEM. All of the study results would be useful for the design of osteochondral construct further manufactured by nano-tech. A three-dimensional model with gradient porous structure is constructed in the environment of Pro/ENGINEERING software.

  9. Morphological and mechanical characterization of chitosan-calcium phosphate composites for potential application as bone-graft substitutes

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    Guilherme Maia Mulder van de Graaf

    Full Text Available Introduction: Bone diseases, aging and traumas can cause bone loss and lead to bone defects. Treatment of bone defects is challenging, requiring chirurgical procedures. Bone grafts are widely used for bone replacement, but they are limited and expensive. Due to bone graft limitations, natural, semi-synthetic, synthetic and composite materials have been studied as potential bone-graft substitutes. Desirable characteristics of bone-graft substitutes are high osteoinductive and angiogenic potentials, biological safety, biodegradability, bone-like mechanical properties, and reasonable cost. Herein, we prepared and characterized potential bone-graft substitutes composed of calcium phosphate (CP - a component of natural bone, and chitosan (CS - a biocompatible biopolymer. Methods CP-CS composites were synthetized, molded, dried and characterized. The effect of drying temperatures (38 and 60 °C on the morphology, porosity and chemical composition of the composites was evaluated. As well, the effects of drying temperature and period of drying (3, 24, 48 and 72 hours on the mechanical properties - compressive strength, modulus of elasticity and relative deformation-of the demolded samples were investigated. Results Scanning electron microscopy and gas adsorption-desorption analyses of the CS-CP composites showed interconnected pores, indicating that the drying temperature played an important role on pores size and distribution. In addition, drying temperature have altered the color (brownish at 60 °C due to Maillard reaction and the chemical composition of the samples, confirmed by FTIR. Conclusion Particularly, prolonged period of drying have improved mechanical properties of the CS-CP composites dried at 38 °C, which can be designed according to the mechanical needs of the replaceable bone.

  10. Potential of magnetic nanofiber scaffolds with mechanical and biological properties applicable for bone regeneration.

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    Singh, Rajendra K; Patel, Kapil D; Lee, Jae Ho; Lee, Eun-Jung; Kim, Joong-Hyun; Kim, Tae-Hyun; Kim, Hae-Won

    2014-01-01

    Magnetic nanofibrous scaffolds of poly(caprolactone) (PCL) incorporating magnetic nanoparticles (MNP) were produced, and their effects on physico-chemical, mechanical and biological properties were extensively addressed to find efficacy for bone regeneration purpose. MNPs 12 nm in diameter were citrated and evenly distributed in PCL solutions up to 20% and then were electrospun into nonwoven nanofibrous webs. Incorporation of MNPs greatly improved the hydrophilicity of the nanofibers. Tensile mechanical properties of the nanofibers (tensile strength, yield strength, elastic modulus and elongation) were significantly enhanced with the addition of MNPs up to 15%. In particular, the tensile strength increase was as high as ∼25 MPa at 15% MNPs vs. ∼10 MPa in pure PCL. PCL-MNP nanofibers exhibited magnetic behaviors, with a high saturation point and hysteresis loop area, which increased gradually with MNP content. The incorporation of MNPs substantially increased the degradation of the nanofibers, with a weight loss of ∼20% in pure PCL, ∼45% in 10% MNPs and ∼60% in 20% MNPs. Apatite forming ability of the nanofibers tested in vitro in simulated body fluid confirmed the substantial improvement gained by the addition of MNPs. Osteoblastic cells favored the MNPs-incorporated nanofibers with significantly improved initial cell adhesion and subsequent penetration through the nanofibers, compared to pure PCL. Alkaline phosphatase activity and expression of genes associated with bone (collagen I, osteopontin and bone sialoprotein) were significantly up-regulated in cells cultured on PCL-MNP nanofibers than those on pure PCL. PCL-MNP nanofibers subcutaneously implanted in rats exhibited minimal adverse tissue reactions, while inducing substantial neoblood vessel formation, which however, greatly limited in pure PCL. In vivo study in radial segmental defects also signified the bone regeneration ability of the PCL-MNP nanofibrous scaffolds. The magnetic, bone

  11. Silver nanoparticle based antibacterial methacrylate hydrogels potential for bone graft applications

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    González-Sánchez, M. Isabel; Perni, Stefano; Tommasi, Giacomo; Morris, Nathanael Glyn; Hawkins, Karl; López-Cabarcos, Enrique; Prokopovich, Polina

    2015-01-01

    Infections are frequent and very undesired occurrences after orthopedic procedures; furthermore, the growing concern caused by the rise in antibiotic resistance is progressively dwindling the efficacy of such drugs. Artificial bone graft materials could solve some of the problems associated with the gold standard use of natural bone graft such as limited bone material, pain at the donor site and rejections if donor tissue is used. We have previously described new acrylate base nanocomposite hydrogels as bone graft materials. In the present paper, we describe the integration of silver nanoparticles in the polymeric mineralized biomaterial to provide non-antibiotic antibacterial activity against Staphylococcus epidermidis and Methicillin-resistant Staphylococcus aureus. Two different crosslinking degrees were tested and the silver nanoparticles were integrated into the composite matrix by means of three different methods: entrapment in the polymeric hydrogel before the mineralization; diffusion during the process of calcium phosphate crystallization and adsorption post-mineralization. The latter being generally the most effective method of encapsulation; however, the adsorption of silver nanoparticles inside the pores of the biomaterial led to a decreasing antibacterial activity for adsorption time longer than 2 days. PMID:25746278

  12. Electrospun hydroxyapatite-functionalized PLLA scaffold: potential applications in sternal bone healing.

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    Rainer, Alberto; Spadaccio, Cristiano; Sedati, Pietro; De Marco, Federico; Carotti, Simone; Lusini, Mario; Vadalà, Gianluca; Di Martino, Alberto; Morini, Sergio; Chello, Massimo; Covino, Elvio; Denaro, Vincenzo; Trombetta, Marcella

    2011-07-01

    Sternal synthesis after median sternotomy, a conventional access practice in thoracic and cardiac surgery, is at the basis of severe complications, often impairing the clinical outcome of surgical interventions. In this work, we propose the use of an acellular biomaterial scaffold, to be interposed across the fracture rime during closure operations, directly exposing the biomaterial to bone marrow, in order to expedite healing process. A rabbit model of median sternotomy was performed and an electrospun scaffold composed of a hydroxyapatite-loaded absorbable biopolymer (poly-L: -lactide), shaped into a fibrillar structure, was used. CT follow-up confirmed a complete healing in the scaffold-treated group 1 week before the control. Histological evaluation demonstrated presence of newly formed bone trabeculae among scaffold fibers showing a higher degree of maturity with respect to the control untreated group. The proposed approach is able to both guide a more rapid healing and modulate inflammatory response across the wound site, resulting in improved healing and tissue remodeling with respect to conventional closure technique.

  13. Scaffold of chitosan-sodium alginate and hydroxyapatite with application potential for bone regeneration

    International Nuclear Information System (INIS)

    Rebelo, Marcia de A.; Alves, Thais F.R.; Lopes, Francielly C.C.N; Oliveira Junior, Jose Martins de; Pontes, Katiusca S.; Fogaca, Bruna A.C.; Chaud, Marco V.

    2015-01-01

    Scaffold for organic tissue regeneration are architectural, three-dimensional, porous, biocompatible and biodegradable devices. The first challenges to be met in the development of these devices to mimic the biomechanical properties of the target tissue. The aim of this study was to develop and to characterize scaffolds composed of chitosan (Ch), sodium alginate (SA), hydroxyapatite (HA). The scaffolds were obtained by lyophilization. HA has been incorporated into the polymer dispersion in Ch-AS concentration of 20 and 60%. The mechanical properties of the scaffold were determined by tensile and compression tests. Swelling capacity was assessed in the presence of simulated saliva, purified water, HCl 0.01M, NaOH 0.01M. The calcium content was quantified using fluorescence X-rays. Analysis of the results indicates that the Qt-AS-HA-60% scaffold obtained by lyophilization meets promising properties for bone tissue regeneration. (author)

  14. Development of an injectable pseudo-bone thermo-gel for application in small bone fractures.

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    Kondiah, Pariksha J; Choonara, Yahya E; Kondiah, Pierre P D; Kumar, Pradeep; Marimuthu, Thashree; du Toit, Lisa C; Pillay, Viness

    2017-03-30

    A pseudo-bone thermo-gel was synthesized and evaluated for its physicochemical, mechanical and rheological properties, with its application to treat small bone fractures. The pseudo-bone thermo-gel was proven to have thermo-responsive properties, behaving as a solution in temperatures below 25°C, and forming a gelling technology when maintained at physiological conditions. Poly propylene fumerate (PPF), Pluronic F127 and PEG-PCL-PEG were strategically blended, obtaining a thermo-responsive delivery system, to mimic the mechanical properties of bone with sufficient matrix hardness and resilience. A Biopharmaceutics Classification System (BCS) class II drug, simvastatin, was loaded in the pseudo-bone thermo-gel, selected for its bone healing properties. In vitro release analysis was undertaken on a series of experimental formulations, with the ideal formulations obtaining its maximum controlled drug release profile up to 14days. Ex vivo studies were undertaken on an induced 4mm diameter butterfly-fractured osteoporotic human clavicle bone samples. X-ray, ultrasound as well as textural analysis, undertaken on the fractured bones before and after treatment displayed significant bone filling, matrix hardening and matrix resilience properties. These characteristics of the pseudo-bone thermo-gel thus proved significant potential for application in small bone fractures. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Engineered Hybrid Scaffolds of Poly(vinyl alcohol/Bioactive Glass for Potential Bone Engineering Applications: Synthesis, Characterization, Cytocompatibility, and Degradation

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    Hermes S. Costa

    2012-01-01

    Full Text Available The synthesis, characterization, preliminary cytocompatibility, and degradation behavior of the hybrids based on 70% Poly(vinyl alcohol and 30% bioactive glass (58SiO2–33CaO–9P2O5, BaG with macroporous tridimensional structure is reported for the first time. The effect of glutaraldehyde covalent crosslinker in the organic-inorganic nanostructures produced and, as a consequence, tailoring the hybrids properties was investigated. The PVA/BaG hybrids scaffolds are characterized by Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (SEM, X-ray diffraction (XRD, and X-ray Microcomputed tomography analysis (μCT. Cytotoxicity assessment is performed by the MTT method with VERO cell culture. Additionally, the hybrid in vitro degradation assay is conducted by measuring the mass loss by soaking in deionized water at 37°C for up to 21 days. The results have clearly shown that it is possible to modify the PVA/BaG hybrids properties and degradation behavior by engineering the structure using different concentrations of the chemical crosslinker. Moreover, these hybrid crosslinked nanostructures have presented 3D hierarchical pore size architecture varying within 10–450 μm and a suitable cytocompatibility for potential use in bone tissue engineering applications.

  16. Characterization of an Olive Flounder Bone Gelatin-Zinc Oxide Nanocomposite Film and Evaluation of Its Potential Application in Spinach Packaging.

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    Beak, Songee; Kim, Hyeri; Song, Kyung Bin

    2017-11-01

    Olive flounder bone gelatin (OBG) was used for a film base material in this study. In addition, zinc oxide nanoparticles (ZnO) were incorporated into the OBG film to prepare a nanocomposite film and to impart antimicrobial activity to it. The tensile strength of the OBG film increased by 6.62 MPa, and water vapor permeability and water solubility decreased by 0.93 × 10 -9 g/m s Pa and 13.79%, respectively, by the addition of ZnO to the OBG film. In particular, the OBG-ZnO film exhibited antimicrobial activity against Listeria monocytogenes. To investigate the applicability of the OBG-ZnO packaging film, fresh spinach was wrapped in this film and stored for a week. The results indicated that the OBG-ZnO film showed antimicrobial activity against L. monocytogenes inoculated on spinach without affecting the quality of spinach, such as vitamin C content and color. Thus, the OBG-ZnO nanocomposite film can be applied as an efficient antimicrobial food packaging material. As a base material of edible films, gelatin was extracted from olive flounder bone, which is fish processing by-product. Olive flounder bone gelatin (OBG) nanocomposite films were prepared with zinc oxide nanoparticles (ZnO). For an application to antimicrobial packaging, spinach was wrapped with the OBG-ZnO nanocomposite film. © 2017 Institute of Food Technologists®.

  17. 1, 6-diisocyanatohexane-extended poly (1, 4-butylene succinate / hydroxyl apatite nano particle scaffolds: Potential materials for bone regeneration applications

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    Kaur, Kulwinder; Singh, K. J.; Anand, Vikas; Bhatia, Gaurav; Nim, Lovedeep; Kaur, Manpreet; Arora, Daljit Singh

    2017-05-01

    Bioresorbable and bioactive scaffolds are promising materials for various biomedical applications including bone regeneration and drug delievrery. Authors present bioactive scaffolds prepared from 1, 6-diisocyanatohexane-extended poly (1, 4-butylene succinate) (PBSu-DCH) with different amount of hydroxyl apatite nanoparticles (nHAp) by solvent casting and particulate leaching techniques. Different weight ratios of nHAp (i.e. 0, 5 and 10 wt %) with fixed weight ratio (i.e. 10 wt %) of PBSu-DCH polymer have been prepared. Scaffolds have been assessed for their morphology, bioactivity, degradation, drug release and biological properties including cytotoxicity, cell attachment using MG-63 cell line and antimicrobial activity. Effectual drug release has been measured by incorporating gentamycin as an antibiotic in the scaffolds. The study is aimed at developing new biodegradable scaffolds to be used in skull, jaw and tooth socket for preserving bone mass.

  18. Bone Conduction Thresholds without Bone Vibrator Application Force.

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    Geal-Dor, Miriam; Chordekar, Shai; Adelman, Cahtia; Sohmer, Haim

    2015-01-01

    Osseous bone conduction (BC) stimulation involves applying the clinical bone vibrator with an application force of about 5 Newton (N) to the skin over the cranial vault of skull bone (e.g., mastoid, forehead). In nonosseous BC (also called soft tissue conduction), the bone vibrator elicits hearing when it is applied to skin sites not over the cranial vault of skull bone, such as the neck. To gain insight into the mechanisms of osseous and nonosseous BC. In general, thresholds were determined with the bone vibrator applied with about 5 N force directly to osseous sites (mastoid, forehead) on the head of the participants, as classically conducted in the clinic, and again without direct physical contact (i.e., 0 N force) achieved by coupling the bone vibrator to gel as in ultrasound diagnostic imaging, on the same or nearby skin sites (nonosseous BC). The participants were equipped with earplugs to minimize air-conducted stimulation. In the first experiment, 10 normal-hearing participants were tested with stimulation (5 and 0 N) at the forehead; in the second experiment, 10 additional normal-hearing participants were tested with stimulation at the mastoid (about 5 N) and at the nearby tragus and cavum concha of the external ear (0 N). The mean thresholds with 0 N were much better than might be expected from classical theories in response to stimulation by a bone vibrator, in the absence of any application force. The differences between the mean thresholds with the 0 N and the 5 N forces depended on condition, site, and stimulus frequency of the comparisons. The difference was 1.5 dB at 1.0 kHz on the forehead; ranged between 10 and 12.5 dB at 1.0 kHz on the cavum and tragus (versus on the mastoid) and at 2.0 and 4.0 kHz on the forehead; 17 and 19 dB at 2.0 kHz on the cavum and tragus (versus on the mastoid); reaching 32 dB only in a single condition (forehead at 0.5 kHz). As it is unlikely that threshold intensity stimulation delivered with 0 N application force could

  19. Demineralized Freeze-Dried Bovine Cortical Bone: Its Potential for Guided Bone Regeneration Membrane

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    David B. Kamadjaja

    2017-01-01

    Full Text Available Background. Bovine pericardium collagen membrane (BPCM had been widely used in guided bone regeneration (GBR whose manufacturing process usually required chemical cross-linking to prolong its biodegradation. However, cross-linking of collagen fibrils was associated with poorer tissue integration and delayed vascular invasion. Objective. This study evaluated the potential of bovine cortical bone collagen membrane for GBR by evaluating its antigenicity potential, cytotoxicity, immune and tissue response, and biodegradation behaviors. Material and Methods. Antigenicity potential of demineralized freeze-dried bovine cortical bone membrane (DFDBCBM was done with histology-based anticellularity evaluation, while cytotoxicity was analyzed using MTT Assay. Evaluation of immune response, tissue response, and biodegradation was done by randomly implanting DFDBCBM and BPCM in rat’s subcutaneous dorsum. Samples were collected at 2, 5, and 7 days and 7, 14, 21, and 28 days for biocompatibility and tissue response-biodegradation study, respectively. Result. DFDBCBM, histologically, showed no retained cells; however, it showed some level of in vitro cytotoxicity. In vivo study exhibited increased immune response to DFDBCBM in early healing phase; however, normal tissue response and degradation rate were observed up to 4 weeks after DFDBCBM implantation. Conclusion. Demineralized freeze-dried bovine cortical bone membrane showed potential for clinical application; however, it needs to be optimized in its biocompatibility to fulfill all requirements for GBR membrane.

  20. Porous hydroxyapatite for artificial bone applications

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    I. Sopyan et al

    2007-01-01

    Full Text Available Hydroxyapatite (HA has been used clinically for many years. It has good biocompatibility in bone contact as its chemical composition is similar to that of bone material. Porous HA ceramics have found enormous use in biomedical applications including bone tissue regeneration, cell proliferation, and drug delivery. In bone tissue engineering it has been applied as filling material for bone defects and augmentation, artificial bone graft material, and prosthesis revision surgery. Its high surface area leads to excellent osteoconductivity and resorbability providing fast bone ingrowth. Porous HA can be produced by a number of methods including conversion of natural bones, ceramic foaming technique, polymeric sponge method, gel casting of foams, starch consolidation, microwave processing, slip casting, and electrophoretic deposition technique. Some of these methods have been combined to fabricate porous HA with improved properties. These combination methods have yielded some promising results. This paper discusses briefly fundamental aspects of porous HA for artificial bone applications as well as various techniques used to prepare porous HA. Some of our recent results on development of porous HA will be presented as well.

  1. Pediatric applications of radionuclide bone imaging

    International Nuclear Information System (INIS)

    Summerville, D.A.; Treves, S.T.

    1988-01-01

    Applications of skeletal scintigraphy in the pediatric population differ significantly from those in the adult population. While the majority of bone scans performed in adults are to detect osseous metastases, bone scans in the pediatric population are performed for a wider variety of conditions. These include (in addition to bony metastases) evaluation of primary bone tumors (both malignant and benign), bone and joint infections, avascular necrosis (AVN), fractures, sports-related injuries, the evaluation of growth disorders (particularly involving the mandible), and a variety of benign orthopedic conditions unique to the childhood period. Thus, the physician interpreting pediatric nuclear medicine bone scans must be acquainted with a variety of disorders not common to the adult population. In this chapter, the authors discuss those aspects of bone scintigraphy that are generally confined to the younger population. In doing so, they have attempted to avoid those aspects of skeletal scintigraphy common to both pediatric and adult populations

  2. Distribution Atlas of Proliferating Bone Marrow in Non-Small Cell Lung Cancer Patients Measured by FLT-PET/CT Imaging, With Potential Applicability in Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Belinda A., E-mail: Belinda.Campbell@petermac.org [Department of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia); Callahan, Jason [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia); Bressel, Mathias [Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, East Melbourne (Australia); Simoens, Nathalie [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia); Everitt, Sarah [Radiotherapy Services, Peter MacCallum Cancer Centre, East Melbourne (Australia); Hofman, Michael S.; Hicks, Rodney J. [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia); Burbury, Kate [Department of Haematology, Peter MacCallum Cancer Centre, East Melbourne (Australia); MacManus, Michael [Department of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia)

    2015-08-01

    Purpose: Proliferating bone marrow is exquisitely sensitive to ionizing radiation. Knowledge of its distribution could improve radiation therapy planning to minimize unnecessary marrow exposure and avoid consequential prolonged myelosuppression. [18F]-Fluoro-3-deoxy-3-L-fluorothymidine (FLT)–positron emission tomography (PET) is a novel imaging modality that provides detailed quantitative images of proliferating tissues, including bone marrow. We used FLT-PET imaging in cancer patients to produce an atlas of marrow distribution with potential clinical utility. Methods and Materials: The FLT-PET and fused CT scans of eligible patients with non-small cell lung cancer (no distant metastases, no prior cytotoxic exposure, no hematologic disorders) were reviewed. The proportions of skeletal FLT activity in 10 predefined bony regions were determined and compared according to age, sex, and recent smoking status. Results: Fifty-one patients were studied: 67% male; median age 68 (range, 31-87) years; 8% never smokers; 70% no smoking in the preceding 3 months. Significant differences in marrow distribution occurred between sex and age groups. No effect was detected from smoking in the preceding 3 months. Using the mean percentages of FLT uptake per body region, we created an atlas of the distribution of functional bone marrow in 4 subgroups defined by sex and age. Conclusions: This atlas has potential utility for estimating the distribution of active marrow in adult cancer patients to guide radiation therapy planning. However, because of interindividual variation it should be used with caution when radiation therapy risks ablating large proportions of active marrow; in such cases, individual FLT-PET scans may be required.

  3. Application of Petri Nets in Bone Remodeling

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    Lingxi Li

    2009-07-01

    Full Text Available Understanding a mechanism of bone remodeling is a challenging task for both life scientists and model builders, since this highly interactive and nonlinear process can seldom be grasped by simple intuition. A set of ordinary differential equations (ODEs have been built for simulating bone formation as well as bone resorption. Although solving ODEs numerically can provide useful predictions for dynamical behaviors in a continuous time frame, an actual bone remodeling process in living tissues is driven by discrete events of molecular and cellular interactions. Thus, an event-driven tool such as Petri nets (PNs, which may dynamically and graphically mimic individual molecular collisions or cellular interactions, seems to augment the existing ODE-based systems analysis. Here, we applied PNs to expand the ODE-based approach and examined discrete, dynamical behaviors of key regulatory molecules and bone cells. PNs have been used in many engineering areas, but their application to biological systems needs to be explored. Our PN model was based on 8 ODEs that described an osteoprotegerin linked molecular pathway consisting of 4 types of bone cells. The models allowed us to conduct both qualitative and quantitative evaluations and evaluate homeostatic equilibrium states. The results support that application of PN models assists understanding of an event-driven bone remodeling mechanism using PN-specific procedures such as places, transitions, and firings.

  4. Degradation pattern of porous CaCO3 and hydroxyapatite microspheres in vitro and in vivo for potential application in bone tissue engineering.

    Science.gov (United States)

    Zhong, Qiwei; Li, Wenhua; Su, Xiuping; Li, Geng; Zhou, Ying; Kundu, Subhas C; Yao, Juming; Cai, Yurong

    2016-07-01

    Despite superior clinical handling, excellent biocompatibility, biodegradation property of calcium phosphate needs to be improved to coincide with the rate of new bone formation. In this study, spherical CaCO3 are fabricated in the presence of the silk sericin and then transformed into porous hydroxyapatite (HAP) microspheres via hydrothermal method. The degradation behavior of obtained CaCO3, HAP and their mixture is first investigated in vitro. The result demonstrates that the weight loss of HAP microspheres are almost 24.3% after immersing in pH 7.40 Tris-HCl buffer solution for 12 weeks, which is far slower than that of spherical CaCO3 (97.5%). The degradation speed of the mixtures depends on the proportion of CaCO3 and HAP. The mixture with higher content of CaCO3 possesses a quicker degradation speed. The obtained CaCO3 and HAP microspheres are injected into subcutaneous tissue of ICR mice with the assistance of sodium alginate. The result in vivo also shows an obvious difference of degradation speed between the obtained CaCO3 and HAP microspheres, implying it is feasible to modulate the degradation property of the mixture through changing the proportion of CaCO3 and HAP The good cytocompatibility of the two kinds of microspheres is proved and a mild inflammation response is observed only at early stage of implantation. The job offers a simple method to modify the degradation properties of biomaterial for potential use in bone tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Terrestrial applications of bone and muscle research in microgravity

    Science.gov (United States)

    Booth, F. W.

    1994-08-01

    Major applications to people on Earth are possible from NASA-sponsored research on bone and muscle which is conducted either in microgravity or on Earth using models mimicking microgravity. In microgravity bone and muscle mass are lost. Humans experience a similar loss under certain conditions on Earth. Bone and muscle loss exist on Earth as humans age from adulthood to senescence, during limb immobilization for healing of orthopedic injuries, during wheelchair confinement because of certain diseases, and during chronic bed rest prescribed for curing of diseases. NASA-sponsored research is dedicated to learning both what cause bone and muscle loss as well as finding out how to prevent this loss. The health ramifications of these discoveries will have major impact. Objective 1.6 of Healthy People 2000, a report from the U.S. Department of Health and Human Services, states that the performance of physical activities that improve muscular strength, muscular endurance, and flexibility is particularly important to maintaining functional independence and social integration in older adults /1/. This objective further states that these types of physical activities are important because they may protect against disability, an event which costs the U.S. economy hugh sums of money. Thus NASA research related to bone and muscle loss has potential major impact on the quality of life in the U.S. Relative to its potential health benefits, NASA and Congressional support of bone and muscle research is funded is a very low level.

  6. Vitamin D and Bone Health; Potential Mechanisms

    Directory of Open Access Journals (Sweden)

    J.J. Strain

    2010-07-01

    Full Text Available Osteoporosis is associated with increased morbidity, mortality and significant economic and health costs. Vitamin D is a secosteriod hormone essential for calcium absorption and bone mineralization which is positively associated with bone mineral density [BMD]. It is well-established that prolonged and severe vitamin D deficiency leads to rickets in children and osteomalacia in adults. Sub-optimal vitamin D status has been reported in many populations but it is a particular concern in older people; thus there is clearly a need for effective strategies to optimise bone health. A number of recent studies have suggested that the role of vitamin D in preventing fractures may be via its mediating effects on muscle function (a defect in muscle function is one of the classical signs of rickets and inflammation. Studies have demonstrated that vitamin D supplementation can improve muscle strength which in turn contributes to a decrease in incidence of falls, one of the largest contributors to fracture incidence. Osteoporosis is often considered to be an inflammatory condition and pro-inflammatory cytokines have been associated with increased bone metabolism. The immunoregulatory mechanisms of vitamin D may thus modulate the effect of these cytokines on bone health and subsequent fracture risk. Vitamin D, therefore, may influence fracture risk via a number of different mechanisms.

  7. Printing bone : the application of 3D fiber deposition for bone tissue engineering

    NARCIS (Netherlands)

    Fedorovich, N.E.

    2011-01-01

    Bone chips are used by orthopaedic surgeons for treating spinal trauma and to augment large bone defects. A potential alternative to autologous bone is regeneration of bone tissue in the lab by developing hybrid implants consisting of osteogenic (stem) cells seeded on supportive matrices.

  8. Glucocorticoid: A potential role in microgravity-induced bone loss

    Science.gov (United States)

    Yang, Jiancheng; Yang, Zhouqi; Li, Wenbin; Xue, Yanru; Xu, Huiyun; Li, Jingbao; Shang, Peng

    2017-11-01

    Exposure of animals and humans to conditions of microgravity, including actual spaceflight and simulated microgravity, results in numerous negative alterations to bone structure and mechanical properties. Although there are abundant researches on bone loss in microgravity, the explicit mechanism is not completely understood. At present, it is widely accepted that the absence of mechanical stimulus plays a predominant role in bone homeostasis disorders in conditions of weightlessness. However, aside from mechanical unloading, nonmechanical factors such as various hormones, cytokines, dietary nutrition, etc. are important as well in microgravity induced bone loss. The stress-induced increase in endogenous glucocorticoid (GC) levels is inevitable in microgravity environments. Moreover, it is well known that GCs have a detrimental effect to bone health at excess concentrations. Therefore, GC plays a potential role in microgravity-induced bone loss. This review summarizeds several studies and their prospective solutions to this hypothesis.

  9. A review of the scientific basis and practical application of a new test of utricular function - ocular vestibular - evoked myogenic potentials to bone-conducted vibration

    NARCIS (Netherlands)

    Curthoys, I. S.; Manzari, L.; Smulders, Y. E.; Burgess, A. M.

    This is a review of recently published papers showing that bone-conducted vibration of the head causes linear acceleration stimulation of both inner ears and this linear acceleration is an effective way of selectively activating otolithic afferent neurons. This simple stimulus is used in a new test

  10. Osteogenesis and angiogenesis: the potential for engineering bone.

    Science.gov (United States)

    Kanczler, J M; Oreffo, R O C

    2008-05-02

    The repair of large bone defects remains a major clinical orthopaedic challenge. Bone is a highly vascularised tissue reliant on the close spatial and temporal connection between blood vessels and bone cells to maintain skeletal integrity. Angiogenesis thus plays a pivotal role in skeletal development and bone fracture repair. Current procedures to repair bone defects and to provide structural and mechanical support include the use of grafts (autologous, allogeneic) or implants (polymeric or metallic). These approaches face significant limitations due to insufficient supply, potential disease transmission, rejection, cost and the inability to integrate with the surrounding host tissue. The engineering of bone tissue offers new therapeutic strategies to aid musculoskeletal healing. Various scaffold constructs have been employed in the development of tissue-engineered bone; however, an active blood vessel network is an essential pre-requisite for these to survive and integrate with existing host tissue. Combination therapies of stem cells and polymeric growth factor release scaffolds tailored to promote angiogenesis and osteogenesis are under evaluation and development actively to stimulate bone regeneration. An understanding of the cellular and molecular interactions of blood vessels and bone cells will enhance and aid the successful development of future vascularised bone scaffold constructs, enabling survival and integration of bioengineered bone with the host tissue. The role of angiogenic and osteogenic factors in the adaptive response and interaction of osteoblasts and endothelial cells during the multi step process of bone development and repair will be highlighted in this review, with consideration of how some of these key mechanisms can be combined with new developments in tissue engineering to enable repair and growth of skeletal fractures. Elucidation of the processes of angiogenesis, osteogenesis and tissue engineering strategies offer exciting future

  11. BONE TUMOR ENVIRONMENT AS POTENTIAL THERAPEUTIC TARGET IN EWING SARCOMA

    Directory of Open Access Journals (Sweden)

    Françoise eREDINI

    2015-12-01

    Full Text Available Ewing sarcoma is the second most common pediatric bone tumor, with three cases per million worldwide. In clinical terms, ES is an aggressive, rapidly fatal malignancy that mainly develops in osseous sites (85%, but also in extraskeletal soft tissue. It spreads naturally to the lungs, bones and bone marrow with poor prognosis in the two latter cases. Bone lesions from primary or secondary (metastases tumors are characterized by extensive bone remodeling, more often due to osteolysis. Osteoclast activation and subsequent bone resorption is responsible for the clinical features of bone tumors including pain, vertebral collapse and spinal cord compression. Based on the vicious cycle concept of tumor cells and bone resorbing cells, drugs which target osteoclasts may be promising agents as adjuvant setting for treating bone tumors, including Ewing sarcoma. There is also increasing evidence that cellular and molecular protagonists present in the bone microenvironment play a part in establishing a favorable niche for tumor initiation and progression. The purpose of this review is to discuss the potential therapeutic value of drugs targeting the bone tumor microenvironment in Ewing Sarcoma. The first part of the review will focus on targeting the bone resorbing function of osteoclasts by means of bisphosphonates (BPs or drugs blocking the pro-resorbing cytokine Receptor Activator of NF-kappa B Ligand (RANKL. Second, the role of this peculiar hypoxic microenvironment will be discussed in the context of resistance to chemotherapy, escape from the immune system, or neo-angiogenesis. Therapeutic interventions based on these specificities could be then proposed in the context of Ewing sarcoma.

  12. Characterization of membranes based on cellulose acetate butyrate/poly(caprolactone)triol/doxycycline and their potential for guided bone regeneration application.

    Science.gov (United States)

    Marques, Morgana Souza; Zepon, Karine Modolon; Petronilho, Fabrícia Cardoso; Soldi, Valdir; Kanis, Luiz Alberto

    2017-07-01

    This paper discusses the feasibility of using membranes based on cellulose acetate butyrate/poly(caprolactone)triol loaded with doxycycline for guided bone regeneration. Those membranes were obtained by solvent casting varying the cellulose acetate butyrate: poly(caprolactone)triol:doxycycline (CAB:PCL-T:DOX) mass ratios and characterized by scanning electron microscopy, differential scanning calorimetry, dynamical mechanical analysis, swelling and weight loss, drug release, in vitro antimicrobial activity and in vivo inflammatory response. Neat CAB and CAB:PCL-T:DOX membranes exhibited inner porous structure, which has a pore-size reduced with increasing of the PCL-T ratio. DSC results demonstrated that the molecular dispersion of the DOX into the CAB:PCL-T membrane was conditioned by PCL-T amount. Elastic modulus reduced noticeably with increased of the PCL-T ratio in the membrane from 2 to 3, while the strain at failure showed an increase of ca. 10-fold on the same condition. The DOX release mechanism from the membranes was found to be Fickian or quasi-Fickian diffusion. Membranes assessed immediately after the preparation, and even as the membranes immersed in synthetic saliva during 7 days, demonstrated significant inhibition in the growth of Staphylococcus aureus and Escherichia coli. Subcutaneous implant test on rat in vivo showed that the CAB:PCL-T:DOX membrane (7:3:1) did not trigger chronic inflammatory responses. These results suggest the feasibility in applying the CAB:PCL-T:DOX membrane as a barrier for guided bone regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Bone loss following knee arthroplasty: potential treatment options.

    Science.gov (United States)

    Vasso, Michele; Beaufils, Philippe; Cerciello, Simone; Schiavone Panni, Alfredo

    2014-04-01

    The management of bone loss is a crucial aspect of the revision knee arthroplasty. Bone loss can hinder the correct positioning and alignment of the prosthetic components, and can prevent the achievement of a stable bone-implant interface. There is still controversy regarding the optimal management of knee periprosthetic bone loss, especially in large defects for which structural grafts, metal or tantalum augments, tantalum cones, porous metaphyseal sleeves, and special prostheses have been advocated. The aim of this review was to analyze all possible causes of bone loss and the most advanced strategies for managing bony deficiency within the knee joint reconstruction. Most significant and recent papers about the management of bone defects during revision knee arthroplasty were carefully analyzed and reviewed to report the most common causes of bone loss and the most effective strategies to manage them. Modular metal and tantalum augmentation showed to provide more stable and durable knee revisions compared to allografts, limited by complications such as graft failure, fracture and resorption. Moreover, modular augmentation may considerably shorten operative times with a potential decrease of complications, above all infection which has been frequently associated to the use of allografts. Modular augmentation may significantly reduce the need for allografting, whose complications appear to limit the long-term success of knee revisions.

  14. Application potential of bone marrow mesenchymal stem cell (BMSCs) based tissue-engineering for spinal cord defect repair in rat fetuses with spina bifida aperta.

    Science.gov (United States)

    Li, Xiaoshuai; Yuan, Zhengwei; Wei, Xiaowei; Li, Hui; Zhao, Guifeng; Miao, Jiaoning; Wu, Di; Liu, Bo; Cao, Songying; An, Dong; Ma, Wei; Zhang, Henan; Wang, Weilin; Wang, Qiushi; Gu, Hui

    2016-04-01

    Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan-gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan-gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region.

  15. A Therapeutic Potential for Marine Skeletal Proteins in Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Bruce Milthorpe

    2013-04-01

    Full Text Available A vital ingredient for engineering bone tissue, in the culture dish, is the use of recombinant matrix and growth proteins to help accelerate the growth of cultivated tissues into clinically acceptable quantities. The skeletal organic matrices of calcifying marine invertebrates are an untouched potential source of such growth inducing proteins. They have the advantage of being ready-made and retain the native state of the original protein. Striking evidence shows that skeleton building bone morphogenic protein-2/4 (BMP and transforming growth factor beta (TGF-β exist within various marine invertebrates such as, corals. Best practice mariculture and the latest innovations in long-term marine invertebrate cell cultivation can be implemented to ensure that these proteins are produced sustainably and supplied continuously. This also guarantees that coral reef habitats are not damaged during the collection of specimens. Potential proteins for bone repair, either extracted from the skeleton or derived from cultivated tissues, can be identified, evaluated and retrieved using chromatography, cell assays and proteomic methods. Due to the current evidence for bone matrix protein analogues in marine invertebrates, together with the methods established for their production and retrieval there is a genuine prospect that they can be used to regenerate living bone for potential clinical use.

  16. Strontium borate glass: potential biomaterial for bone regeneration.

    Science.gov (United States)

    Pan, H B; Zhao, X L; Zhang, X; Zhang, K B; Li, L C; Li, Z Y; Lam, W M; Lu, W W; Wang, D P; Huang, W H; Lin, K L; Chang, J

    2010-07-06

    Boron plays important roles in many life processes including embryogenesis, bone growth and maintenance, immune function and psychomotor skills. Thus, the delivery of boron by the degradation of borate glass is of special interest in biomedical applications. However, the cytotoxicity of borate glass which arises with the rapid release of boron has to be carefully considered. In this study, it was found that the incorporation of strontium into borate glass can not only moderate the rapid release of boron, but also induce the adhesion of osteoblast-like cells, SaOS-2, thus significantly increasing the cyto-compatibility of borate glass. The formation of multilayers of apatite with porous structure indicates that complete degradation is optimistic, and the spread of SaOS-2 covered by apatite to form a sandwich structure may induce bone-like tissue formation at earlier stages. Therefore, such novel strontium-incorporated borosilicate may act as a new generation of biomaterial for bone regeneration, which not only renders boron as a nutritious element for bone health, but also delivers strontium to stimulate formation of new bones.

  17. Potential biomedical applications of ion beam technology

    Science.gov (United States)

    Banks, B. A.; Weigand, A. J.; Van Kampen, C. L.; Babbush, C. A.

    1976-01-01

    Electron bombardment ion thrusters used as ion sources have demonstrated a unique capability to vary the surface morphology of surgical implant materials. The microscopically rough surface texture produced by ion beam sputtering of these materials may result in improvements in the biological response and/or performance of implanted devices. Control of surface roughness may result in improved attachment of the implant to soft tissue, hard tissue, bone cement, or components deposited from blood. Potential biomedical applications of ion beam texturing discussed include: vascular prostheses, artificial heart pump diaphragms, pacemaker fixation, percutaneous connectors, orthopedic prosthesis fixation, and dental implants.

  18. An Update into the Application of Nanotechnology in Bone Healing.

    Science.gov (United States)

    Brannigan, K; Griffin, M

    2016-01-01

    Bone differs from other organs in that it can regenerate and remodel without scar formation. There are instances of trauma, congenital bone disorder, bone disease and bone cancer where this is not possible. Without bone grafts and implants, deformity and disability would result. Human bone grafts are limited in their management of large or non-union fractures. In response, synthetic bone grafts and implants are available to the Orthopaedic Surgeon. Unfortunately these also have their limitations and associated complications. Nanotechnology involves the research, design and manufacture of materials with a grain size less than 100nm. Nano-phase materials follow the laws of quantum physics, not classical mechanics, resulting in novel behavioural differences compared to conventional counterparts. Past, present and future nanotechnology in bone healing literature is reviewed and discussed. The article highlights concepts which are likely to be instrumental to the future of nanotechnology in bone healing. Nanotechnology in bone healing is an emerging field within Orthopaedic Surgery. There is a requirement for bone healing technologies which are biochemically and structurally similar to bone. Nanotechnology is a potential solution as the arrangement of bone includes nanoscopic collagen fibres and hydroxyapatite. This review centers on the novel field of nanotechnology in bone healing with discussion focusing on advances in bone grafts, implants, diagnostics and drug delivery. The concept of nanotechnology was first introduced in 1959. Current nanoproducts for bone healing include nano-HA-paste-ostim and nano-beta-tricalcium phosphate-Vitoss. Nanophase technologies are considered to be superior bone healing solutions. Limited safety data and issues regarding cost and mass scale production require further research into this exciting field.

  19. Osteogenic potential of a chalcone in a critical-size defect in rat calvaria bone.

    Science.gov (United States)

    Ortolan, Xana Raquel; Fenner, Bruna Proiss; Mezadri, Telmo José; Tames, David Rivero; Corrêa, Rogério; de Campos Buzzi, Fátima

    2014-07-01

    This study describes the bone formation stimulated by the application of a type of chalcone to critical-size defects in rat calvarial bone. Sixty female Wistar rats were divided into 6 groups of 10 animals per group: control (no treatment), vehicle (vaseline) and the chalcone (1-phenyl-3-(4-chlorophenyl)-2-propen-1-one) suspended in vaseline at 10%. A critical-size defect of 5 mm was prepared using a trephine in the calvarial bone, after which the treatment was applied, in a single dose, according to the experimental group. The samples were evaluated macroscopically using ImageJ software, and histologically 30 and 45 days after surgery. At 30 days after surgery, there was significant bone formation (p chalcone, compared with the other groups. Many active osteoblasts were observed adjacent to the borders of the newly formed bone tissue. 45 days after surgery in the chalcone group, the surgical defects showed complete bone closure. The results of this study suggest that chalcone has significant potential to induce the formation of new bone. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  20. Graded porous polyurethane foam: A potential scaffold for oro-maxillary bone regeneration

    International Nuclear Information System (INIS)

    Giannitelli, S.M.; Basoli, F.; Mozetic, P.; Piva, P.; Bartuli, F.N.; Luciani, F.; Arcuri, C.; Trombetta, M.; Rainer, A.; Licoccia, S.

    2015-01-01

    Bone tissue engineering applications demand for biomaterials offering a substrate for cell adhesion, migration, and proliferation, while inferring suitable mechanical properties to the construct. In the present study, polyurethane (PU) foams were synthesized to develop a graded porous material—characterized by a dense shell and a porous core—for the treatment of oro-maxillary bone defects. Foam was synthesized via a one-pot reaction starting from a polyisocyanate and a biocompatible polyester diol, using water as a foaming agent. Different foaming conditions were examined, with the aim of creating a dense/porous functional graded material that would perform at the same time as an osteoconductive scaffold for bone defect regeneration and as a membrane-barrier to gingival tissue ingrowth. The obtained PU was characterized in terms of morphological and mechanical properties. Biocompatibility assessment was performed in combination with bone-marrow-derived human mesenchymal stromal cells (hBMSCs). Our findings confirm that the material is potentially suitable for guided bone regeneration applications. - Highlights: • Graded porous polyurethane foams were synthesized via a one-pot foaming reaction. • The inner porous core might act as a scaffold for guided bone regeneration. • A dense outer shell was introduced to act as a barrier to gingival tissue ingrowth. • The synthesized foams were non-toxic and supportive of hBMSC adhesion

  1. Graded porous polyurethane foam: A potential scaffold for oro-maxillary bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Giannitelli, S.M. [Department of Engineering, Tissue Engineering Unit, Università Campus Bio-Medico di Roma, Rome (Italy); Basoli, F. [Department of Chemical Science and Technology, University of Rome “Tor Vergata”, Rome (Italy); Mozetic, P. [Department of Engineering, Tissue Engineering Unit, Università Campus Bio-Medico di Roma, Rome (Italy); Piva, P.; Bartuli, F.N.; Luciani, F. [University of Rome “Tor Vergata”, Rome (Italy); Arcuri, C. [Department of Periodontics, University of Rome “Tor Vergata”, Rome (Italy); U.O.C.C. Odontostomatology, “S. Giovanni Calibita, Fatebenefratelli” Hospital, Rome (Italy); Trombetta, M. [Department of Engineering, Tissue Engineering Unit, Università Campus Bio-Medico di Roma, Rome (Italy); Rainer, A., E-mail: a.rainer@unicampus.it [Department of Engineering, Tissue Engineering Unit, Università Campus Bio-Medico di Roma, Rome (Italy); Licoccia, S. [Department of Chemical Science and Technology, University of Rome “Tor Vergata”, Rome (Italy)

    2015-06-01

    Bone tissue engineering applications demand for biomaterials offering a substrate for cell adhesion, migration, and proliferation, while inferring suitable mechanical properties to the construct. In the present study, polyurethane (PU) foams were synthesized to develop a graded porous material—characterized by a dense shell and a porous core—for the treatment of oro-maxillary bone defects. Foam was synthesized via a one-pot reaction starting from a polyisocyanate and a biocompatible polyester diol, using water as a foaming agent. Different foaming conditions were examined, with the aim of creating a dense/porous functional graded material that would perform at the same time as an osteoconductive scaffold for bone defect regeneration and as a membrane-barrier to gingival tissue ingrowth. The obtained PU was characterized in terms of morphological and mechanical properties. Biocompatibility assessment was performed in combination with bone-marrow-derived human mesenchymal stromal cells (hBMSCs). Our findings confirm that the material is potentially suitable for guided bone regeneration applications. - Highlights: • Graded porous polyurethane foams were synthesized via a one-pot foaming reaction. • The inner porous core might act as a scaffold for guided bone regeneration. • A dense outer shell was introduced to act as a barrier to gingival tissue ingrowth. • The synthesized foams were non-toxic and supportive of hBMSC adhesion.

  2. Strontium borate glass: potential biomaterial for bone regeneration

    OpenAIRE

    Pan, H. B.; Zhao, X. L.; Zhang, X.; Zhang, K. B.; Li, L. C.; Li, Z. Y.; Lam, W. M.; Lu, W. W.; Wang, D. P.; Huang, W. H.; Lin, K. L.; Chang, J.

    2009-01-01

    Boron plays important roles in many life processes including embryogenesis, bone growth and maintenance, immune function and psychomotor skills. Thus, the delivery of boron by the degradation of borate glass is of special interest in biomedical applications. However, the cytotoxicity of borate glass which arises with the rapid release of boron has to be carefully considered. In this study, it was found that the incorporation of strontium into borate glass can not only moderate the rapid relea...

  3. Evaluation of the Healing Potential of Demineralized Dentin Matrix Fixed with Recombinant Human Bone Morphogenetic Protein-2 in Bone Grafts

    Directory of Open Access Journals (Sweden)

    Sang-Yun Kim

    2017-09-01

    Full Text Available We aimed to evaluate the efficacy of demineralized dentin matrix (DDM fixed with recombinant human bone morphogenetic protein-2 (rhBMP-2 through an experimental and a clinical study. Unilateral upper second and third premolars of eight beagles were extracted. A mucoperiosteal flap was elevated around the extraction socket, and a bone defect was made using a surgical drill. Each DDM was fixed with rhBMP-2, and autogenous bone was grafted at the bone defect area with a collagenous membrane. The beagles were euthanized at two, four, eight, and 12 weeks after receiving the bone graft. Block specimens involving grafted bone and surrounding natural bone were extracted. A total of 23 patients who received bone grafts using human DDM fixed with rhBMP-2 (AutoBT BMP with implant placements (36 implants; maxilla: 14, mandible: 22 were selected. The implant stability, marginal bone loss, and clinical outcome were evaluated. Three trephine cores were harvested fourmonths after bone grafting, and histologic examination was performed. In the histological evaluation performed four weeks after the bone graft, autogenous bone showed 52% new bone formation and DDM fixed with rhBMP-2 showed 33% new bone formation. Twelve weeks after the bone graft, autogenous bone showed 75% new bone formation and DDM fixed with rhBMP-2 showed 48% new bone formation. In the clinical study, favorable osseointegration was obtained in 35 out of 36 implant sites (one case of osseointegration failure. In all cases, severe complications were not observed. Histomorphometrically, new bone formation was observed in 14.98% of the cases. The residual DDM particles were 6.22%. AutoBT BMP provides good osteoinductive and osteoconductive potential and clinical efficacy.

  4. Rapid prototyping technology and its application in bone tissue engineering.

    Science.gov (United States)

    Yuan, Bo; Zhou, Sheng-Yuan; Chen, Xiong-Sheng

    Bone defects arising from a variety of reasons cannot be treated effectively without bone tissue reconstruction. Autografts and allografts have been used in clinical application for some time, but they have disadvantages. With the inherent drawback in the precision and reproducibility of conventional scaffold fabrication techniques, the results of bone surgery may not be ideal. This is despite the introduction of bone tissue engineering which provides a powerful approach for bone repair. Rapid prototyping technologies have emerged as an alternative and have been widely used in bone tissue engineering, enhancing bone tissue regeneration in terms of mechanical strength, pore geometry, and bioactive factors, and overcoming some of the disadvantages of conventional technologies. This review focuses on the basic principles and characteristics of various fabrication technologies, such as stereolithography, selective laser sintering, and fused deposition modeling, and reviews the application of rapid prototyping techniques to scaffolds for bone tissue engineering. In the near future, the use of scaffolds for bone tissue engineering prepared by rapid prototyping technology might be an effective therapeutic strategy for bone defects.

  5. Changes of Surface Electric Potential of Bones Depending on Their Age

    OpenAIRE

    Freimanis, E; Dehtjars, J; Vendiņa, V

    2014-01-01

    The aim of this research was to determine how surface electric potential of bones changes with their age and how it correlates with mechanical properties of bones. Surface electric potential was measured in 6 cross-sectional zones of the tibia. Changes of bones surface electric potential with age were determined and correlations between surface electric potential and mechanical properties were derived.

  6. Interleukin-10 Inhibits Bone Resorption: A Potential Therapeutic Strategy in Periodontitis and Other Bone Loss Diseases

    OpenAIRE

    Zhang, Qian; Chen, Bin; Yan, Fuhua; Guo, Jianbin; Zhu, Xiaofeng; Ma, Shouzhi; Yang, Wenrong

    2014-01-01

    Periodontitis and other bone loss diseases, decreasing bone volume and strength, have a significant impact on millions of people with the risk of tooth loss and bone fracture. The integrity and strength of bone are maintained through the balance between bone resorption and bone formation by osteoclasts and osteoblasts, respectively, so the loss of bone results from the disruption of such balance due to increased resorption or/and decreased formation of bone. The goal of therapies for diseases...

  7. 3D-Printing Composite Polycaprolactone-Decellularized Bone Matrix Scaffolds for Bone Tissue Engineering Applications.

    Science.gov (United States)

    Rindone, Alexandra N; Nyberg, Ethan; Grayson, Warren L

    2017-05-11

    Millions of patients worldwide require bone grafts for treatment of large, critically sized bone defects from conditions such as trauma, cancer, and congenital defects. Tissue engineered (TE) bone grafts have the potential to provide a more effective treatment than current bone grafts since they would restore fully functional bone tissue in large defects. Most bone TE approaches involve a combination of stem cells with porous, biodegradable scaffolds that provide mechanical support and degrade gradually as bone tissue is regenerated by stem cells. 3D-printing is a key technique in bone TE that can be used to fabricate functionalized scaffolds with patient-specific geometry. Using 3D-printing, composite polycaprolactone (PCL) and decellularized bone matrix (DCB) scaffolds can be produced to have the desired mechanical properties, geometry, and osteoinductivity needed for a TE bone graft. This book chapter will describe the protocols for fabricating and characterizing 3D-printed PCL:DCB scaffolds. Moreover, procedures for culturing adipose-derived stem cells (ASCs) in these scaffolds in vitro will be described to demonstrate the osteoinductivity of the scaffolds.

  8. Methods and application of bone densitometry in clinical diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Wahner, H.W.; Riggs, B.L.

    1986-01-01

    With the awareness of osteoporosis as a major health problem for an aging population, there is great interest in early recognition and treatment of abnormal bone loss. Effective prevention of bone loss has to occur prior to the occurrence of irreparable damage. Standard radiographic procedures are not sensitive enough for the task. Therefore, a number of alternative procedures to estimate bone loss have been developed over the years, ranging from efforts to quantitate information obtained from radiographic images to sophisticated procedures such as neutron activation analysis or procedures based on the Compton scatter phenomenon. Only two procedures, photon absorptiometry and computed tomography (CT), have emerged as applicable for routine clinical use. In photon absorptiometry the entire bone mineral (cortical and trabecular bone) of a specific skeletal site is measured. CT allows measuring of bone mineral of trabecular or cortical bone alone. Normally, bone mass reaches a maximum in the third decade and then continuously declines. This age-related bone loss is greater in women in whom an accelerated rate of loss occurs at the menopause. When bone density reaches a critical fracture threshold, skeletal fractures occur (spine, hip, and distal long bones). The age at which this critical fracture threshold is reached depends on the maximal bone mass achieved in early adulthood and the rate of loss with increasing age. With the exception of NaF, present-day therapeutic efforts only retard or prevent bone loss but do not significantly add bone mineral to the skeleton. Recognition of high-risk groups and early treatment are therefore required. 79 references.

  9. Graded porous polyurethane foam: a potential scaffold for oro-maxillary bone regeneration.

    Science.gov (United States)

    Giannitelli, S M; Basoli, F; Mozetic, P; Piva, P; Bartuli, F N; Luciani, F; Arcuri, C; Trombetta, M; Rainer, A; Licoccia, S

    2015-06-01

    Bone tissue engineering applications demand for biomaterials offering a substrate for cell adhesion, migration, and proliferation, while inferring suitable mechanical properties to the construct. In the present study, polyurethane (PU) foams were synthesized to develop a graded porous material-characterized by a dense shell and a porous core-for the treatment of oro-maxillary bone defects. Foam was synthesized via a one-pot reaction starting from a polyisocyanate and a biocompatible polyester diol, using water as a foaming agent. Different foaming conditions were examined, with the aim of creating a dense/porous functional graded material that would perform at the same time as an osteoconductive scaffold for bone defect regeneration and as a membrane-barrier to gingival tissue ingrowth. The obtained PU was characterized in terms of morphological and mechanical properties. Biocompatibility assessment was performed in combination with bone-marrow-derived human mesenchymal stromal cells (hBMSCs). Our findings confirm that the material is potentially suitable for guided bone regeneration applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Macroporous synthetic hydroxyapatite bioceramics for bone substitute applications

    CSIR Research Space (South Africa)

    Thomas, ME

    1999-08-01

    Full Text Available An improved strategy is described for the manufacture of macroporous hydroxyapatite bioceramics for bone substitute applications. This is based on a modified fugitive phase technique, which allows production of relatively open, high-strength devices...

  11. Digital image processing of bone - Problems and potentials

    Science.gov (United States)

    Morey, E. R.; Wronski, T. J.

    1980-01-01

    The development of a digital image processing system for bone histomorphometry and fluorescent marker monitoring is discussed. The system in question is capable of making measurements of UV or light microscope features on a video screen with either video or computer-generated images, and comprises a microscope, low-light-level video camera, video digitizer and display terminal, color monitor, and PDP 11/34 computer. Capabilities demonstrated in the analysis of an undecalcified rat tibia include the measurement of perimeter and total bone area, and the generation of microscope images, false color images, digitized images and contoured images for further analysis. Software development will be based on an existing software library, specifically the mini-VICAR system developed at JPL. It is noted that the potentials of the system in terms of speed and reliability far exceed any problems associated with hardware and software development.

  12. Potential Applications of Manual Games,

    Science.gov (United States)

    1984-02-01

    34 just because some electronic equipment is used to keep track of logistics, combat results, and force status. Even a highly computerized game like...D-A152 541 POTENTIAL APPLICATIONS OF MANUAL GAMES (U) RAND CORP ii SANTA MONICA CA T A BROW~N FEB 84 RAND/P-6957 UNCLASI7FIED F/G 12/2 N El..I 111 1...128 112.5 111 m; * _ 1.8 I1111 ’I’ll MICROCOPY RESOLUTION TEST CHART NATI NAl fii~ t1 RI 1A L4k, I POTENTIAL APPLICATIONS OF MANUJAL GAMES Lfl N Lfl

  13. Diatomic interaction potential theory applications

    CERN Document Server

    Goodisman, Jerry

    2013-01-01

    Diatomic Interaction Potential Theory, Volume 2: Applications discusses the variety of applicable theoretical material and approaches in the calculations for diatomic systems in their ground states. The volume covers the descriptions and illustrations of modern calculations. Chapter I discusses the calculation of the interaction potential for large and small values of the internuclear distance R (separated and united atom limits). Chapter II covers the methods used for intermediate values of R, which in principle means any values of R. The Hartree-Fock and configuration interaction schemes des

  14. Operculum bone carp (cyprinus carprio sp.) scaffold is a new potential xenograft material: a preliminary study

    Science.gov (United States)

    Kartiwa, A.; Abbas, B.; Pandansari, P.; Prahasta, A.; Nandini, M.; Fadhlillah, M.; Subroto, T.; Panigoro, R.

    2017-02-01

    Orbital floor fracture with extensive bone loss, would cause herniation of the orbital tissue into the maxillary sinus. Graft implantation should be done on the orbital fracture with extensive bone loss. Different types of grafts have their own characteristics and advantages. Xenograft has been widely studied for use in bone defects. This study was to investigate cyprinus carprio sp. opercula bone as a potential xenograft. The aim of this study was to investigate based on EDS chemical analysis using a ZAF Standardless Method of Quantitative Analysis (Oxide) and SEM examination conducted in the laboratory of Mathematics, Institute of Technology Bandung. Particularly the mass ratio of Ca and P (5.8/3:47), the result is 1.67. This is equivalent to the stoichiometric Hydroxyapatite (HA) (Aoki H, 1991, Science and medical applications of hydroxyapatite, Tokyo: Institute for Medical and Engineering, Tokyo Medical and Dental University). C N O that there is an element of protein/amino acid collagen compound, serves as a matrix together with HA. As shown in the SEM analysis that the matrix is a porous sheet-shaped (oval) that interconnect with each other, which is good scaffold. The pore is composed of large pores >200 microns and smaller pores between the large pores with a size smaller or equal to 10 microns that can serve for the attachment of osteoblast cell. In conclusion, Opercula bone carp (cyprinus carprio sp.) scaffold could be a new potential xenograft material.

  15. MicroRNA Regulation in Osteogenic and Adipogenic Differentiation of Bone Mesenchymal Stem Cells and its Application in Bone Regeneration.

    Science.gov (United States)

    Li, Binbin

    2018-01-01

    Bone mesenchymal stem cells (BMSCs) are multipotent stromal cells providing a useful cell source for treating bone diseases and metabolic disorders. BMSCs fate determination and lineage progression are controlled by multiple cytokines, transcriptional factors, signaling pathways, and microRNAs (miRNAs). MiRNAs are small non-coding RNAs that inhibit the posttranscriptional gene expression or degrade their targets. They are closely involved in controlling the key steps of osteogenesis and adipogenesis of BMSCs. We aim to summarize the roles of miRNAs and their pathways in regulating osteogenic and adipogenic differentiation of BMSCs, and sketch its preliminary applications in bone regeneration. We reviewed the published literature about the microRNA regulation in osteogenic and adipogenic differentiation of BMSCs. Most of miRNAs are expressed in BMSCs, perform as negative regulators of osteogenesis and have bidirectional effects on adipogenesis. Runx2 and PPARγ are two key transcriptional factors in osteogenesis and adipogenesis, respectively. Anti-miRNAs or miRNA mimics is potential therapeutic strategy to repress pathological miRNAs for cellular therapies to bone diseases. The preliminary applications of miRNAs in BMSCs strongly suggested their bright future in bone regeneration. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Potential therapeutic applications of biosurfactants.

    Science.gov (United States)

    Gudiña, Eduardo J; Rangarajan, Vivek; Sen, Ramkrishna; Rodrigues, Lígia R

    2013-12-01

    Biosurfactants have recently emerged as promising molecules for their structural novelty, versatility, and diverse properties that are potentially useful for many therapeutic applications. Mainly due to their surface activity, these molecules interact with cell membranes of several organisms and/or with the surrounding environments, and thus can be viewed as potential cancer therapeutics or as constituents of drug delivery systems. Some types of microbial surfactants, such as lipopeptides and glycolipids, have been shown to selectively inhibit the proliferation of cancer cells and to disrupt cell membranes causing their lysis through apoptosis pathways. Moreover, biosurfactants as drug delivery vehicles offer commercially attractive and scientifically novel applications. This review covers the current state-of-the-art in biosurfactant research for therapeutic purposes, providing new directions towards the discovery and development of molecules with novel structures and diverse functions for advanced applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Hydroxyapatite nanoparticles: preparation, characterization, and evaluation of their potential use in bone targeting: an animal study.

    Science.gov (United States)

    Maia, Ana Luiza C; Cavalcante, Carolina H; Souza, Marina G F de; Ferreira, Carolina de A; Rubello, Domenico; Chondrogiannis, Sotirios; Cardoso, Valbert N; Ramaldes, Gilson A; Barros, André L B de; Soares, Daniel C F

    2016-07-01

    Hydroxyapatite is used as a drug-delivery system for bone therapy applications because of its biocompatibility, bioactivity, and osteoconductive properties. In addition, hydroxyapatite nanoparticles (HApN) might be used as a theranostic probe. The aim of this study was to prepare and characterize hydroxyapatite mesoporous nanoparticles, and radiolabel these nanoparticles with technetium-99m (Tc). Moreover, biodistribution studies were carried out in healthy mice. HApN were synthesized and characterized. Tc-HApN was prepared by adding Tc-pertechnetate to a dispersion of HApN in the presence of stannous chloride. Radiochemical purity and in-vitro stability were determined. The circulation time of Tc-HApN was determined by measuring blood radioactivity in healthy mice. In addition, biodistribution studies were carried out in healthy mice at 1 and 4 h after injection. Tc-HApN showed high radiochemical purity (98.7±0.2%) and in-vitro stability until 24 h. Tc-HApN levels in blood decreased in a biphasic manner, with an α half-life of 1.8 min and a β half-life of 126.9 min. High uptake was achieved in the liver and spleen because of the macrophage uptake. Furthermore, bone uptake was higher than that of the surrounding muscle, resulting in high bone-to-muscle ratios. HApN were synthesized successfully with suitable characteristics for in-vivo applications. Tc-HApN was prepared and showed high stability. Tc-HApN presented increasing bone uptake over time, showing a higher affinity to bone tissues in contrast to surrounding muscle. The present results, together with further studies, may indicate a potential application of HApN as a nanocarrier for bone diseases.

  18. Interleukin-10 Inhibits Bone Resorption: A Potential Therapeutic Strategy in Periodontitis and Other Bone Loss Diseases

    Directory of Open Access Journals (Sweden)

    Qian Zhang

    2014-01-01

    Full Text Available Periodontitis and other bone loss diseases, decreasing bone volume and strength, have a significant impact on millions of people with the risk of tooth loss and bone fracture. The integrity and strength of bone are maintained through the balance between bone resorption and bone formation by osteoclasts and osteoblasts, respectively, so the loss of bone results from the disruption of such balance due to increased resorption or/and decreased formation of bone. The goal of therapies for diseases of bone loss is to reduce bone loss, improve bone formation, and then keep healthy bone density. Current therapies have mostly relied on long-term medication, exercise, anti-inflammatory therapies, and changing of the life style. However there are some limitations for some patients in the effective treatments for bone loss diseases because of the complexity of bone loss. Interleukin-10 (IL-10 is a potent anti-inflammatory cytokine, and recent studies have indicated that IL-10 can contribute to the maintenance of bone mass through inhibition of osteoclastic bone resorption and regulation of osteoblastic bone formation. This paper will provide a brief overview of the role of IL-10 in bone loss diseases and discuss the possibility of IL-10 adoption in therapy of bone loss diseases therapy.

  19. Interleukin-10 inhibits bone resorption: a potential therapeutic strategy in periodontitis and other bone loss diseases.

    Science.gov (United States)

    Zhang, Qian; Chen, Bin; Yan, Fuhua; Guo, Jianbin; Zhu, Xiaofeng; Ma, Shouzhi; Yang, Wenrong

    2014-01-01

    Periodontitis and other bone loss diseases, decreasing bone volume and strength, have a significant impact on millions of people with the risk of tooth loss and bone fracture. The integrity and strength of bone are maintained through the balance between bone resorption and bone formation by osteoclasts and osteoblasts, respectively, so the loss of bone results from the disruption of such balance due to increased resorption or/and decreased formation of bone. The goal of therapies for diseases of bone loss is to reduce bone loss, improve bone formation, and then keep healthy bone density. Current therapies have mostly relied on long-term medication, exercise, anti-inflammatory therapies, and changing of the life style. However there are some limitations for some patients in the effective treatments for bone loss diseases because of the complexity of bone loss. Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine, and recent studies have indicated that IL-10 can contribute to the maintenance of bone mass through inhibition of osteoclastic bone resorption and regulation of osteoblastic bone formation. This paper will provide a brief overview of the role of IL-10 in bone loss diseases and discuss the possibility of IL-10 adoption in therapy of bone loss diseases therapy.

  20. 3D Tissue Scaffold Printing On Custom Artificial Bone Applications

    Directory of Open Access Journals (Sweden)

    Betül ALDEMİR

    2015-01-01

    Full Text Available Production of defect-matching scaffolds is the most critical step in custom artificial bone applications. Three dimensional printing (3DP is one of the best techniques particularly for custom designs on artificial bone applications because of the high controllability and design independency. Our long-term aim is to implant an artificial custom bone that is cultured with patient's own mesenchymal stem cells after determining defect architecture on patient's bone by using CT-scan and printing that defect-matching 3D scaffold with appropriate nontoxic materials. In this study, preliminary results of strength and cytotoxicity measurements of 3D printed scaffolds with modified calcium sulfate compositepowder (MCSCP were presented. CAD designs were created and MCSCP were printed by a 3D printer (3DS, Visijet, PXL Core. Some samples were covered with salt solution in order to harden the samples. MCSCP and salt coated MCSCP were the two experimental groups in this study. Cytotoxicity and mechanical experiments were performed after surface examination withscanning electron microscope (SEM and light microscope. Tension tests were performed for MCSCP and salt coated MCSCP samples. The 3D scaffolds were sterilized with ethylene oxide gas sterilizer, ventilated and conditioned with DMEM (10% FBS. L929 mouse fibroblast cells were cultured on scaffolds (3 repetitive and cell viability was determined using MTT analysis. According to the mechanical results, the MCSCP group stands until average 71,305 N, while salt coated MCSCP group stands until 21,328N. Although the strength difference between two groups is statistically significant (p=0.001, Mann-Whitney U, elastic modulus is not (MCSCP=1,186Pa, salt coated MCSCP=1,169Pa, p=0.445. Cell viability (MTT analysis results on day 1, 3, and 5 demonstrated thatscaffolds hadno toxic effect to the L929 mouse fibroblast cells. Consequently, 3D printed samples with MCSCP could potentially be a strong alternative

  1. Cobalt doped proangiogenic hydroxyapatite for bone tissue engineering application.

    Science.gov (United States)

    Kulanthaivel, Senthilguru; Roy, Bibhas; Agarwal, Tarun; Giri, Supratim; Pramanik, Krishna; Pal, Kunal; Ray, Sirsendu S; Maiti, Tapas K; Banerjee, Indranil

    2016-01-01

    The present study delineates the synthesis and characterization of cobalt doped proangiogenic-osteogenic hydroxyapatite. Hydroxyapatite samples, doped with varying concentrations of bivalent cobalt (Co(2+)) were prepared by the ammoniacal precipitation method and the extent of doping was measured by ICP-OES. The crystalline structure of the doped hydroxyapatite samples was confirmed by XRD and FTIR studies. Analysis pertaining to the effect of doped hydroxyapatite on cell cycle progression and proliferation of MG-63 cells revealed that the doping of cobalt supported the cell viability and proliferation up to a threshold limit. Furthermore, such level of doping also induced differentiation of the bone cells, which was evident from the higher expression of differentiation markers (Runx2 and Osterix) and better nodule formation (SEM study). Western blot analysis in conjugation with ELISA study confirmed that the doped HAp samples significantly increased the expression of HIF-1α and VEGF in MG-63 cells. The analysis described here confirms the proangiogenic-osteogenic properties of the cobalt doped hydroxyapatite and indicates its potential application in bone tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Applications of carbon nanomaterials in bone tissue engineering.

    Science.gov (United States)

    Venkatesan, Jayachandran; Pallela, Ramjee; Kim, Se-Kwon

    2014-10-01

    In the biomedical field, remarkable advancements have been made in artificial biomaterials for treating bone loss or defects. A variety of synthetic polymers, natural polymers and bioceramics are being used to develop artificial bones. Many natural and synthetic biomaterials, which are being investigated for their physiochemical role in vivo, are currently in the clinical trial stage. Carbon-based prostheses are promising materials that mimic the natural function of bone, e.g., mechanical strength. Recently, carbon-based bone materials, such as carbon nanotubes and graphene, have been widely investigated as potential solutions to several biomedical problems. This review summarizes the biophysicochemical and biomedical properties of carbon nanomaterials composed of polymer and ceramic structures and discusses their functionality in bone tissue engineering.

  3. Biological Evaluation of Flexible Polyurethane/Poly l-Lactic Acid Composite Scaffold as a Potential Filler for Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Yuk Fai Lui

    2017-09-01

    Full Text Available Degradable bone graft substitute for large-volume bone defects is a continuously developing field in orthopedics. With the advance in biomaterial in past decades, a wide range of new materials has been investigated for their potential in this application. When compared to common biopolymers within the field such as PLA or PCL, elastomers such as polyurethane offer some unique advantages in terms of flexibility. In cases of bone defect treatments, a flexible soft filler can help to establish an intimate contact with surrounding bones to provide a stable bone-material interface for cell proliferation and ingrowth of tissue. In this study, a porous filler based on segmented polyurethane incorporated with poly l-lactic acid was synthesized by a phase inverse salt leaching method. The filler was put through in vitro and in vivo tests to evaluate its potential in acting as a bone graft substitute for critical-sized bone defects. In vitro results indicated there was a major improvement in biological response, including cell attachment, proliferation and alkaline phosphatase expression for osteoblast-like cells when seeded on the composite material compared to unmodified polyurethane. In vivo evaluation on a critical-sized defect model of New Zealand White (NZW rabbit indicated there was bone ingrowth along the defect area with the introduction of the new filler. A tight interface formed between bone and filler, with osteogenic cells proliferating on the surface. The result suggested polyurethane/poly l-lactic acid composite is a material with the potential to act as a bone graft substitute for orthopedics application.

  4. Preparation and characterization of an iron oxide-hydroxyapatite nanocomposite for potential bone cancer therapy.

    Science.gov (United States)

    Sneha, Murugesan; Sundaram, Nachiappan Meenakshi

    2015-01-01

    Recently, multifunctional magnetic nanostructures have been found to have potential applications in biomedical and tissue engineering. Iron oxide nanoparticles are biocompatible and have distinctive magnetic properties that allow their use in vivo for drug delivery and hyperthermia, and as T2 contrast agents for magnetic resonance imaging. Hydroxyapatite is used frequently due to its well-known biocompatibility, bioactivity, and lack of toxicity, so a combination of iron oxide and hydroxyapatite materials could be useful because hydroxyapatite has better bone-bonding ability. In this study, we prepared nanocomposites of iron oxide and hydroxyapatite and analyzed their physicochemical properties. The results suggest that these composites have superparamagnetic as well as biocompatible properties. This type of material architecture would be well suited for bone cancer therapy and other biomedical applications.

  5. Molecular mechanism and potential targets for bone metastasis

    International Nuclear Information System (INIS)

    Iguchi, Haruo

    2007-01-01

    The incidence of bone metastasis has been increasing in all cancers in recent years. Bone metastasis is associated with substantial morbidity, including bone pain, pathological fracture, neurological deficit and/or hypercalcemia. Thus, the management of bone metastasis in patients is a clinically significant issue. In the process of bone metastasis, the primary mechanism responsible for bone destruction is cancer cell-mediated stimulation of osteoclastic bone resorption, which results in osteolysis and release of various growth factors from the bone matrix. These growth factors are prerequisites for successful colonization and subsequent invasive growth of cancer cells in bone, which is called a 'vicious cycle.' Thus, it is important to elucidate what molecules are involved in this step of bone destruction, and the understanding of these molecular mechanisms could lead to develop molecular-target therapies for bone metastasis. Bisphosphonates introduced in the treatment for bone metastasis have been shown to reduce skeletal morbidity. In Japan, the most potent bisphosphonate, zoledronate (ZOMETA), was introduced in this past April, and a phase III clinical trial of humanized anti-receptor activator of NF-κB ligand (RANKL) monoclonal antibody (Denosumab) against bone metastasis is under way as a global study. These new agents, which are targeted to osteoclasts, are considered to be standard management in the care of bone metastasis patients in combination with chemotherapy and/or hormone therapy. (author)

  6. In vitro osteoinductive potential of porous monetite for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Bernadine Idowu

    2014-05-01

    Full Text Available Tissue engineering–based bone grafts are emerging as a viable alternative treatment modality to repair and regenerate tissues damaged as a result of disease or injury. The choice of the biomaterial component is a critical determinant of the success of the graft or scaffold; essentially, it must induce and allow native tissue integration, and most importantly mimic the hierarchical structure of the native bone. Calcium phosphate bioceramics are widely used in orthopaedics and dentistry applications due to their similarity to bone mineral and their ability to induce a favourable biological response. One such material is monetite, which is biocompatible, osteoconductive and has the ability to be resorbed under physiological conditions. The osteoinductive properties of monetite in vivo are known; however, little is known of the direct effect on osteoinduction of human mesenchymal stem cells in vitro. In this study, we evaluated the potential of monetite to induce and sustain human mesenchymal stem cells towards osteogenic differentiation. Human mesenchymal stem cells were seeded on the monetite scaffold in the absence of differentiating factors for up to 28 days. The gene expression profile of bone-specific markers in cells on monetite scaffold was compared to the control material hydroxyapatite. At day 14, we observed a marked increase in alkaline phosphatase, osteocalcin and osteonectin expressions. This study provides evidence of a suitable material that has potential properties to be used as a tissue engineering scaffold.

  7. In vitro osteoinductive potential of porous monetite for bone tissue engineering

    Science.gov (United States)

    Idowu, Bernadine; Cama, Giuseppe; Deb, Sanjukta

    2014-01-01

    Tissue engineering–based bone grafts are emerging as a viable alternative treatment modality to repair and regenerate tissues damaged as a result of disease or injury. The choice of the biomaterial component is a critical determinant of the success of the graft or scaffold; essentially, it must induce and allow native tissue integration, and most importantly mimic the hierarchical structure of the native bone. Calcium phosphate bioceramics are widely used in orthopaedics and dentistry applications due to their similarity to bone mineral and their ability to induce a favourable biological response. One such material is monetite, which is biocompatible, osteoconductive and has the ability to be resorbed under physiological conditions. The osteoinductive properties of monetite in vivo are known; however, little is known of the direct effect on osteoinduction of human mesenchymal stem cells in vitro. In this study, we evaluated the potential of monetite to induce and sustain human mesenchymal stem cells towards osteogenic differentiation. Human mesenchymal stem cells were seeded on the monetite scaffold in the absence of differentiating factors for up to 28 days. The gene expression profile of bone-specific markers in cells on monetite scaffold was compared to the control material hydroxyapatite. At day 14, we observed a marked increase in alkaline phosphatase, osteocalcin and osteonectin expressions. This study provides evidence of a suitable material that has potential properties to be used as a tissue engineering scaffold. PMID:24904727

  8. Bone Alkaline Phosphatase and Tartrate-Resistant Acid Phosphatase: Potential Co-regulators of Bone Mineralization.

    Science.gov (United States)

    Halling Linder, Cecilia; Ek-Rylander, Barbro; Krumpel, Michael; Norgård, Maria; Narisawa, Sonoko; Millán, José Luis; Andersson, Göran; Magnusson, Per

    2017-07-01

    Phosphorylated osteopontin (OPN) inhibits hydroxyapatite crystal formation and growth, and bone alkaline phosphatase (BALP) promotes extracellular mineralization via the release of inorganic phosphate from the mineralization inhibitor inorganic pyrophosphate (PPi). Tartrate-resistant acid phosphatase (TRAP), produced by osteoclasts, osteoblasts, and osteocytes, exhibits potent phosphatase activity towards OPN; however, its potential capacity as a regulator of mineralization has not previously been addressed. We compared the efficiency of BALP and TRAP towards the endogenous substrates for BALP, i.e., PPi and pyridoxal 5'-phosphate (PLP), and their impact on mineralization in vitro via dephosphorylation of bovine milk OPN. TRAP showed higher phosphatase activity towards phosphorylated OPN and PPi compared to BALP, whereas the activity of TRAP and BALP towards PLP was comparable. Bovine milk OPN could be completely dephosphorylated by TRAP, liberating all its 28 phosphates, whereas BALP dephosphorylated at most 10 phosphates. OPN, dephosphorylated by either BALP or TRAP, showed a partially or completely attenuated phosphorylation-dependent inhibitory capacity, respectively, compared to native OPN on the formation of mineralized nodules. Thus, there are phosphorylations in OPN important for inhibition of mineralization that are removed by TRAP but not by BALP. In conclusion, our data indicate that both BALP and TRAP can alleviate the inhibitory effect of OPN on mineralization, suggesting a potential role for TRAP in skeletal mineralization. Further studies are warranted to explore the possible physiological relevance of TRAP in bone mineralization.

  9. The potential of isotopically enriched magnesium to study bone implant degradation in vivo.

    Science.gov (United States)

    Draxler, Johannes; Martinelli, Elisabeth; Weinberg, Annelie M; Zitek, Andreas; Irrgeher, Johanna; Meischel, Martin; Stanzl-Tschegg, Stefanie E; Mingler, Bernhard; Prohaska, Thomas

    2017-03-15

    This pilot study highlights the substantial potential of using isotopically enriched (non-radioactive) metals to study the fate of biodegradable metal implants. It was possible to show that magnesium (Mg) release can be observed by combining isotopic mass spectrometry and isotopic pattern deconvolution for data reduction, even at low amounts of Mg released a from slowly degrading 26 Mg enriched (>99%) Mg metal. Following implantation into rats, structural in vivo changes were monitored by μCT. Results showed that the applied Mg had an average degradation rate of 16±5μmyear -1 , which corresponds with the degradation rate of pure Mg. Bone and tissue extraction was performed 4, 24, and 52weeks after implantation. Bone cross sections were analyzed by laser ablation inductively coupled plasma mass spectrometry (ICP-MS) to determine the lateral 26 Mg distribution. The 26 Mg/ 24 Mg ratios in digested tissue and excretion samples were analyzed by multi collector ICP-MS. Isotope pattern deconvolution in combination with ICP-MS enabled detection of Mg pin material in amounts as low as 200ppm in bone tissues and 20ppm in tissues up to two fold increased Mg levels with a contribution of pin-derived Mg of up to 75% (4weeks) and 30% (24weeks) were found adjacent to the implant. After complete degradation, no visual bone disturbance or residual pin-Mg could be detected in cortical bone. In organs, increased Δ 26 Mg/ 24 Mg values up to 16‰ were determined compared to control samples. Increased Δ 26 Mg/ 24 Mg values were detected in serum samples at a constant total Mg level. In contrast to urine, feces did not show a shift in the 26 Mg/ 24 Mg ratios. This investigation showed that the organism is capable of handling excess Mg well and that bones fully recover after degradation. Magnesium alloys as bone implants have faced increasing attention over the past years. In vivo degradation and metabolism studies of these implant materials have shown the promising application in

  10. Climbing exercise increases bone mass and trabecular bone turnover through transient regulation of marrow osteogenic and osteoclastogenic potentials in mice.

    Science.gov (United States)

    Mori, Toshiharu; Okimoto, Nobukazu; Sakai, Akinori; Okazaki, Yuichi; Nakura, Nariaki; Notomi, Takuya; Nakamura, Toshitaka

    2003-11-01

    To investigate the relationship between the effects of bone turnover and bone marrow cell development in bone cells, we developed a mouse voluntary climbing exercise model. Climbing exercise increased bone volume and transient osteogenic potential of bone marrow. This model would be suitable for investigating the mechanistic roles of mechanical loading. The relationship between bone mass gain and local bone formation and resorption in mechanically loaded bone is not well understood. Sixty-five C57BL/6J mice, 8 weeks of age, were assigned to five groups: a baseline control and two groups each of ground control and climbing exercise mice for 2 and 4 weeks. Mice were housed in a 100-cm tower and had to climb toward a bottle placed at the top to drink water. Compared with the ground control, bone mineral density of the left femur increased in the climbing mice at 4 weeks. At 2 and 4 weeks, bone formation rate (BFR/BS) of periosteal surface, the cross-sectional area, and moment of inertia were increased in the climbing mice, whereas BFR/BS and eroded surface (ES/BS) of endosteal surface did not differ. The trabecular bone volume (BV/TV) of the proximal tibia increased in climbing mice, and osteoclast surface (Oc.S/BS) and osteoclast number decreased at 2 weeks. At 4 weeks, there were increases in BV/TV and parameters of bone formation, including mineralized surface, mineral apposition rate, and bone formation rate. In marrow cell cultures from the tibia, the number of alkaline phosphatase+ colony forming units-fibroblastic and the area of mineralized nodule formation in climbing mice were increased, and the number of osteoclast-like TRACP+ multinucleated cells was lower at 2 weeks. At 4 weeks, these parameters recovered to the levels of the ground controls. Our results indicate that climbing increased trabecular bone volume and reduced bone resorption, with a subsequent increase in bone formation. Intermittent climbing downregulates marrow osteoclastogenic cells and

  11. Effect of anisotropy on stress-induced electrical potentials in bovine bone using ultrasound irradiation

    Science.gov (United States)

    Matsukawa, S.; Makino, T.; Mori, S.; Koyama, D.; Takayanagi, S.; Mizuno, K.; Yanagitani, T.; Matsukawa, M.

    2017-04-01

    The bone fracture healing mechanism of the low-intensity pulsed ultrasound technique is not yet clearly understood. In our previous study, the electrical potentials induced in bone were successfully measured by focusing on piezoelectricity in the MHz range. Bone is composed of collagen and hydroxyapatite and has strong anisotropy. The purpose of this study is to investigate the effects of bone anisotropy on the electrical potentials induced by ultrasound irradiation. For this study, ultrasound bone transducers were fabricated using cortical bovine bone plates as piezoelectric devices. An ultrasound of 7.4 kPapeak-peak (i.e., the peak-to-peak pressure value) was used to irradiate the side surface of each bone plate. Electrical potentials induced in the bone plate were then measured by varying the wave propagation direction in the plate. The peak-to-peak values of these ultrasonically induced electrical potentials were found to vary with changes in the ultrasound propagation direction in the bone sample. The potential was maximized at an inclination of approximately 45° to the bone axis but was minimized around the three orthogonal directions. These maxima and minima ranged from 28 to 33 μVpeak-peak and from 5 to 12 μVpeak-peak, respectively. Additionally, our ultrasound results indicated a change in polarity due to bone anisotropy in the MHz range.

  12. Cobalt doped proangiogenic hydroxyapatite for bone tissue engineering application

    Energy Technology Data Exchange (ETDEWEB)

    Kulanthaivel, Senthilguru [Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India); Roy, Bibhas [Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 (India); Agarwal, Tarun [Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India); Giri, Supratim [Department of Chemistry, National Institute of Technology, Rourkela, Odisha 769008 (India); Pramanik, Krishna; Pal, Kunal; Ray, Sirsendu S. [Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India); Maiti, Tapas K. [Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 (India); Banerjee, Indranil, E-mail: indraniliit@gmail.com [Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India)

    2016-01-01

    ABSTRACT: The present study delineates the synthesis and characterization of cobalt doped proangiogenic–osteogenic hydroxyapatite. Hydroxyapatite samples, doped with varying concentrations of bivalent cobalt (Co{sup 2+}) were prepared by the ammoniacal precipitation method and the extent of doping was measured by ICP–OES. The crystalline structure of the doped hydroxyapatite samples was confirmed by XRD and FTIR studies. Analysis pertaining to the effect of doped hydroxyapatite on cell cycle progression and proliferation of MG-63 cells revealed that the doping of cobalt supported the cell viability and proliferation up to a threshold limit. Furthermore, such level of doping also induced differentiation of the bone cells, which was evident from the higher expression of differentiation markers (Runx2 and Osterix) and better nodule formation (SEM study). Western blot analysis in conjugation with ELISA study confirmed that the doped HAp samples significantly increased the expression of HIF-1α and VEGF in MG-63 cells. The analysis described here confirms the proangiogenic–osteogenic properties of the cobalt doped hydroxyapatite and indicates its potential application in bone tissue engineering. - Highlights: • Cobalt (Co{sup +2}) doped hydroxyapatite (Co-HAp) can be prepared by the wet chemical method. • The concentration of Co{sup +2} influences the physico-chemical properties of HAp. • Co-HAp was found to be biocompatible and osteogenic. • Co-HAp enhanced cellular VEGF secretion through HIF-1α stabilization. • The optimum biological performance of Co-HAp was achieved for 0.33% (w/w) Co{sup +2} doping.

  13. Bone--bone marrow interface (endosteum) potential relationship of microenvironments in the regulation of response to internal emitters

    International Nuclear Information System (INIS)

    Wilson, F.D.; Pool, R.R.; Stitzel, K.; Momeni, M.H.

    1976-01-01

    The interface between bone and bone marrow is examined in relation to radiation effects, with attention to new concepts of hematopoiesis. Such concepts propose a functional role of stroma in regulating the commitment of pluripotent stem cells as well as in the production of colony stimulating activity (CSA) including candidate granulopoietin(s). Morphologic examples are included, underlining the concept that stroma (including bone) and hematopoietic elements respond as a functional unit to injury to marrow elements. The methylcellulose bone marrow culture system is reviewed as it may relate to a method for quantitation of hematopoietic colonies (CFU-C), humoral regulators for granulopoiesis (CSA), and potentially as a method of quantitating mesenchymal progenitor populations (PFU-C). Based on these and other observations cited, a model depicting a tentative positioning of cells at risk relative to bone-seeking radionuclides is presented

  14. Application of direct digital radiography of nasal bone

    International Nuclear Information System (INIS)

    Gao Dengfa; Wang Haijun; Zhang Ailian; Wang Yulin

    2005-01-01

    Objective: To research the application value of direct digital radiograph (DDR ) in nasal bone imaging. Methods: One hundred cases were examined by DDR, 30 cases of them were examined by two methods both DDR and conventional radiography. All digital images were post-processed with 'MUSICA' (Multi-Scale Image Contrast Amplification), incision and largamente, analyzed and diagnosed by experienced two radiologists and two technicians. Results: One hundred cases of nasal bone, soft tissue of nose were showed excellent in DDR, and satisfactory cases were 95 and 92, respectively. Forty-six cases of nasal bone fractures were found. Thirty cases were examined by both DDR and conventional radiography, images of nasal bone, soft tissue of nose were showed, satisfactory cases were 28 in DDR; and satisfactory cases were 6 (χ 2 =20.05, P 2 =15.06, P 2 =5.14, P<0.05) in conventional and digital radiography, respectively. Conclusion: DDR images of nasal bone, soft tissue of nose was excellent, more fractures were discovered than conventional radiography. Image quality of DDR is better than conventional radiography in nasal bone imaging. (authors)

  15. Potential Therapeutic Use of Relaxin in Healing Cranial Bone Defects

    Science.gov (United States)

    2016-08-01

    incorporation of bone marrow-derived angio- and osteogenic progenitor cells into the lesion. This hormone / growth factor has numerous biological...and bone marrow progenitor cells at the lesion site by immunofluorescence. In addition, we quantitate bone growth and blood vessel density by...contributing Co-Is and Staff; animal husbandry; transport of mice to the various laboratories for procedures; coordination with Veterinary Staff for

  16. Vestibular Evoked Myogenic Potential Produced by Bone-Conducted Stimuli: A Study on its Basics and Clinical Applications in Patients With Conductive and Sensorineural Hearing Loss and a Group With Vestibular Schawannoma

    Directory of Open Access Journals (Sweden)

    Parvane Mahdi

    2013-06-01

    Full Text Available Introduction: Vestibular evoked myogenic potential (VEMP has recently been broadly studied in vestibular disorders. As it is evoked by loud sound stimulation, even mild conductive hearing loss may affect VEMP results. Bone-conducted (BC stimulus is an alternative stimulation for evoking this response. This study aims to assess the characteristics of BC-VEMP in different groups of patients.   Materials and Methods: We performed a cross sectional analysis on 20 healthy volunteers with normal pure-tone audiometry as a control group; and on a group of patients consisted of 20 participants with conductive hearing loss, five with bilateral sensorineural hearing loss and four with vestibular schawannoma. AC and BC-VEMP were performed in all participants.   Results: In control group the VEMP responses to both kinds of stimuli had an acceptable morphology and consisted of p13 and n23 waves. Latency value of these main components in each type of stimulus was not significantly different (P>0.05. However, the mean amplitude was larger in BC modality than AC stimulation (P=0.025. In the group with conductive hearing loss, the VEMP response was absent in fifteen (46.87% of the 32 ears using the AC method, whereas all (100% displayed positive elicitability of VEMP by BC method. Normal VEMP responses in both stimuli were evoked in all patients with sensorineural hearing loss. In patients with unilateral vestibular schwannomas (VS, 2 (50.00% had neither AC-VEMP nor BC-VEMP. Conclusion:  Auditory stimuli delivered by bone conduction can evoke VEMP response. These responses are of vestibular origin and can be used in vestibular evaluation of patients with conductive hearing loss.

  17. Vestibular Evoked Myogenic Potential Produced by Bone-Conducted Stimuli: A Study on its Basics and Clinical Applications in Patients with Conductive and Sensorineural Hearing Loss and a Group with Vestibular Schawannoma.

    Science.gov (United States)

    Mahdi, Parvane; Amali, Amin; Pourbakht, Akram; Karimi Yazdi, Alireza; Bassam, Ali

    2013-06-01

    Vestibular evoked myogenic potential (VEMP) has recently been broadly studied in vestibular disorders. As it is evoked by loud sound stimulation, even mild conductive hearing loss may affect VEMP results. Bone-conducted (BC) stimulus is an alternative stimulation for evoking this response. This study aims to assess the characteristics of BC-VEMP in different groups of patients. We performed a cross sectional analysis on 20 healthy volunteers with normal pure-tone audiometry as a control group; and on a group of patients consisted of 20 participants with conductive hearing loss, five with bilateral sensorineural hearing loss and four with vestibular schawannoma. AC and BC-VEMP were performed in all participants. In control group the VEMP responses to both kinds of stimuli had an acceptable morphology and consisted of p13 and n23 waves. Latency value of these main components in each type of stimulus was not significantly different (P>0.05). However, the mean amplitude was larger in BC modality than AC stimulation (P=0.025). In the group with conductive hearing loss, the VEMP response was absent in fifteen (46.87%) of the 32 ears using the AC method, whereas all (100%) displayed positive elicitability of VEMP by BC method. Normal VEMP responses in both stimuli were evoked in all patients with sensorineural hearing loss. In patients with unilateral vestibular schwannomas (VS), 2 (50.00%) had neither AC-VEMP nor BC-VEMP. Auditory stimuli delivered by bone conduction can evoke VEMP response. These responses are of vestibular origin and can be used in vestibular evaluation of patients with conductive hearing loss.

  18. Bone regeneration potential of sub-microfibrous membranes with ...

    African Journals Online (AJOL)

    Conclusion: The results indicate that biodegradable PCL sub-microfibrous membrane produced by electrospinning process seems to have excellent biocompatibility, and may be used as a scaffold for bone tissue engineering. Keywords: Biocompatibility, Hard tissue, Biomaterial availability, Bone remodeling, Polylactic acid, ...

  19. Application of VEGFA and FGF-9 Enhances Angiogenesis, Osteogenesis and Bone Remodeling in Type 2 Diabetic Long Bone Regeneration

    Science.gov (United States)

    Wallner, Christoph; Schira, Jessica; Wagner, Johannes Maximilian; Schulte, Matthias; Fischer, Sebastian; Hirsch, Tobias; Richter, Wiltrud; Abraham, Stephanie; Kneser, Ulrich; Lehnhardt, Marcus; Behr, Björn

    2015-01-01

    Although bone regeneration is typically a reliable process, type 2 diabetes is associated with impaired or delayed healing processes. In addition, angiogenesis, a crucial step in bone regeneration, is often altered in the diabetic state. In this study, different stages of bone regeneration were characterized in an unicortical bone defect model comparing transgenic type 2 diabetic (db-/db-) and wild type (WT) mice in vivo. We investigated angiogenesis, callus formation and bone remodeling at early, intermediate and late time points by means of histomorphometry as well as protein level analyses. In order to enhance bone regeneration, defects were locally treated with recombinant FGF-9 or VEGFA. Histomorphometry of aniline blue stained sections indicated that bone regeneration is significantly decreased in db-/db- as opposed to WT mice at intermediate (5 days post operation) and late stages (7 days post operation) of bone regeneration. Moreover, immunohistochemical analysis revealed significantly decreased levels of RUNX-2, PCNA, Osteocalcin and PECAM-1 in db-/db- defects. In addition, osteoclastogenesis is impaired in db-/db- indicating altered bone remodeling. These results indicate significant impairments in angiogenesis and osteogenesis in type 2 diabetic bones. Importantly, angiogenesis, osteogenesis and bone remodeling could be reconstituted by application of recombinant FGF-9 and, in part, by VEGFA application. In conclusion, our study demonstrates that type 2 diabetes affects angiogenesis, osteogenesis and subsequently bone remodeling, which in turn leads to decreased bone regeneration. These effects could be reversed by local application of FGF-9 and to a lesser degree VEGFA. These data could serve as a basis for future therapeutic applications aiming at improving bone regeneration in the type 2 diabetic patient population. PMID:25742620

  20. Application of AMOR in craniofacial rabbit bone bioengineering.

    Science.gov (United States)

    Freire, Marcelo; Choi, Jeong-Ho; Nguyen, Anthony; Chee, Young Deok; Kook, Joong-Ki; You, Hyung-Keun; Zadeh, Homayoun H

    2015-01-01

    Endogenous molecular and cellular mediators modulate tissue repair and regeneration. We have recently described antibody mediated osseous regeneration (AMOR) as a novel strategy for bioengineering bone in rat calvarial defect. This entails application of anti-BMP-2 antibodies capable of in vivo capturing of endogenous osteogenic BMPs (BMP-2, BMP-4, and BMP-7). The present study sought to investigate the feasibility of AMOR in other animal models. To that end, we examined the efficacy of a panel of anti-BMP-2 monoclonal antibodies (mAbs) and a polyclonal Ab immobilized on absorbable collagen sponge (ACS) to mediate bone regeneration within rabbit calvarial critical size defects. After 6 weeks, de novo bone formation was demonstrated by micro-CT imaging, histology, and histomorphometric analysis. Only certain anti-BMP-2 mAb clones mediated significant in vivo bone regeneration, suggesting that the epitopes with which anti-BMP-2 mAbs react are critical to AMOR. Increased localization of BMP-2 protein and expression of osteocalcin were observed within defects, suggesting accumulation of endogenous BMP-2 and/or increased de novo expression of BMP-2 protein within sites undergoing bone repair by AMOR. Considering the ultimate objective of translation of this therapeutic strategy in humans, preclinical studies will be necessary to demonstrate the feasibility of AMOR in progressively larger animal models.

  1. Conotoxins: Therapeutic Potential and Application

    Directory of Open Access Journals (Sweden)

    Richard T. Layer

    2006-04-01

    Full Text Available The pharmacological variety of conotoxins, diverse peptides found in the venoms of marine cone snails, is well recognized. Venoms from each of the estimated 500 species of cone snails contain 50 to 200 distinct biologically active peptides. Most conotoxins characterized to date target receptors and ion channels of excitable tissues, such as ligandgated nicotinic acetylcholine, N-methyl-D-aspartate, and type 3 serotonin receptors, as well as voltage-gated calcium, sodium, and potassium channels, and G-protein-coupled receptors including α-adrenergic, neurotensin, and vasopressin receptors, and the norepinephrine transporter. Several conotoxins have shown promise in preclinical models of pain, convulsive disorders, stroke, neuromuscular block, and cardioprotection. The pharmacological selectivity of the conotoxins, coupled with the safety and efficacy demonstrated in preclinical models, has led to their investigation as human therapeutic agents. In the following review, we will survey the pharmacology and therapeutic rationale of those conotoxins with potential clinical application, and discuss the unique challenges that each will face in the course of their transition from venom component to human therapeutic.

  2. Diffusion of Protease into Meat & Bone Meal for Solubility Improvement and Potential Inactivation of the BSE Prion

    OpenAIRE

    Coll, Brian A.; Garcia, Rafael A.; Marmer, William N.

    2007-01-01

    Background Government-imposed feed bans have created a need for new applications for meat & bone meal (MBM). Many potential new applications require MBM protein to be both soluble and free of infectious prion. Treatment with protease is generally effective in reducing insoluble, thermally-denatured proteins to soluble peptides. It has been reported in the literature that certain proteases, including Versazyme™, are able to degrade infectious prions in a system where the prions are readily acc...

  3. Multimodal imaging of bone metastases: From preclinical to clinical applications

    Directory of Open Access Journals (Sweden)

    Stephan Ellmann

    2015-10-01

    Full Text Available Metastases to the skeletal system are commonly observed in cancer patients, highly affecting the patients' quality of life. Imaging plays a major role in detection, follow-up, and molecular characterisation of metastatic disease. Thus, imaging techniques have been optimised and combined in a multimodal and multiparametric manner for assessment of complementary aspects in osseous metastases. This review summarises both application of the most relevant imaging techniques for bone metastasis in preclinical models and the clinical setting.

  4. Design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite as a potential bone graft substitute material

    Science.gov (United States)

    Florschutz, Anthony Vatroslav

    Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were

  5. The potential application of stem cell in dentistry

    Directory of Open Access Journals (Sweden)

    Ketut Suardita

    2006-12-01

    Full Text Available Stem cells are generally defined as cells that have the capacity to self-renewal and differentiate to specialize cell. There are two kinds of stem cell, embryonic stem cell and adult stem cells. Stem cell therapy has been used to treat diseases including Parkinson’s and Alzheimer’s diseases, spinal cord injury, stroke, burns, heart diseases, diabetes, osteoarthritis, and rheumatoid arthritis. Stem cells were found in dental pulp, periodontal ligament, and alveolar bone marrow. Because of their potential in medical therapy, stem cells were used to regenerate lost or damage teeth and periodontal structures. This article discusses the potential application of stem cells for dental field.

  6. [Progress of in vivo study on degradable magnesium alloys application as bone-implant materials].

    Science.gov (United States)

    Qi, Zhengrong; Zhang, Qiang; Yin, Yi; Wang, Yan

    2012-11-01

    To review the progress of in vivo study on degradable magnesium alloys application as bone-implant materials. Recent literature was extensively reviewed and summarized, concerning the in vivo study on degradable magnesium alloys as orthopaedic implants. Magnesium alloys possess a natural ability to degrade via corrosion in vivo, which is promising candidate material for orthopaedic medical device applications. A great progress has been made to improve in vivo performance and integration with bone tissue. However, the degradation mechanism of magnesium-based materials in the physiological environment and long-term effect on body are not available. The modulation of the corrosion rate of magnesium alloys must also be accomplished. Magnesium alloys have the potential to serve as degradable implants for orthopaedic applications, but a great deal of further investigation is still necessary.

  7. Estimates of Green potentials. Applications

    International Nuclear Information System (INIS)

    Danchenko, V I

    2003-01-01

    Optimal Cartan-type covers by hyperbolic discs of carriers of Green α-potentials are obtained in a simply connected domain in the complex plane and estimates of the potentials outside the carriers are presented. These results are applied to problems on the separation of singularities of analytic and harmonic functions. For instance, uniform and integral estimates in terms of Green capacities of components of meromorphic functions are obtained

  8. Tricalcium phosphate/hydroxyapatite (TCP-HA) bone scaffold as potential candidate for the formation of tissue engineered bone.

    Science.gov (United States)

    Sulaiman, Shamsul Bin; Keong, Tan Kok; Cheng, Chen Hui; Saim, Aminuddin Bin; Idrus, Ruszymah Bt Hj

    2013-06-01

    Various materials have been used as scaffolds to suit different demands in tissue engineering. One of the most important criteria is that the scaffold must be biocompatible. This study was carried out to investigate the potential of HA or TCP/HA scaffold seeded with osteogenic induced sheep marrow cells (SMCs) for bone tissue engineering. HA-SMC and TCP/HA-SMC constructs were induced in the osteogenic medium for three weeks prior to implantation in nude mice. The HA-SMC and TCP/HA-SMC constructs were implanted subcutaneously on the dorsum of nude mice on each side of the midline. These constructs were harvested after 8 wk of implantation. Constructs before and after implantation were analyzed through histological staining, scanning electron microscope (SEM) and gene expression analysis. The HA-SMC constructs demonstrated minimal bone formation. TCP/HA-SMC construct showed bone formation eight weeks after implantation. The bone formation started on the surface of the ceramic and proceeded to the centre of the pores. H&E and Alizarin Red staining demonstrated new bone tissue. Gene expression of collagen type 1 increased significantly for both constructs, but more superior for TCP/HA-SMC. SEM results showed the formation of thick collagen fibers encapsulating TCP/HA-SMC more than HA-SMC. Cells attached to both constructs surface proliferated and secreted collagen fibers. The findings suggest that TCP/HA-SMC constructs with better osteogenic potential compared to HA-SMC constructs can be a potential candidate for the formation of tissue engineered bone.

  9. Ethylene oxide gas sterilization does not reduce the osteoinductive potential of demineralized bone in rats

    DEFF Research Database (Denmark)

    Solheim, E; Pinholt, E M; Bang, G

    1995-01-01

    It has been shown that different sterilization procedures of demineralized bone may influence its osteoinductive properties. The aim of this study was to evaluate the effect of ethylene oxide sterilization for 1, 3, and 6 hours on the osteoinductive potential of allogeneic demineralized bone...... without prior sterilization of the material, whereas the demineralized bone implanted in Groups B, C, and D had been sterilized in ethylene oxide gas for 1, 3, or 6 hours, respectively, and aerated for 48 hours. At 4 weeks postoperatively, bone formation was evaluated quantitatively by strontium 85 uptake...

  10. [Application status of rapid prototyping technology in artificial bone based on reverse engineering].

    Science.gov (United States)

    Fang, Ao; Zheng, Min; Fan, Ding

    2015-02-01

    Artificial bone replacement has made an important contribution to safeguard human health and improve the quality of life. The application requirements of rapid prototyping technology based on reverse engineering in individualized artificial bone with individual differences are particularly urgent. This paper reviewed the current research and applications of rapid prototyping and reverse engineering in artificial bone. The research developments and the outlook of bone kinematics and dynamics simulation are also introduced.

  11. Perivascular cells and tissue engineering: Current applications and untapped potential.

    Science.gov (United States)

    Avolio, Elisa; Alvino, Valeria V; Ghorbel, Mohamed T; Campagnolo, Paola

    2017-03-01

    The recent development of tissue engineering provides exciting new perspectives for the replacement of failing organs and the repair of damaged tissues. Perivascular cells, including vascular smooth muscle cells, pericytes and other tissue specific populations residing around blood vessels, have been isolated from many organs and are known to participate to the in situ repair process and angiogenesis. Their potential has been harnessed for cell therapy of numerous pathologies; however, in this Review we will discuss the potential of perivascular cells in the development of tissue engineering solutions for healthcare. We will examine their application in the engineering of vascular grafts, cardiac patches and bone substitutes as well as other tissue engineering applications and we will focus on their extensive use in the vascularization of engineered constructs. Additionally, we will discuss the emerging potential of human pericytes for the development of efficient, vascularized and non-immunogenic engineered constructs. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Bone marrow concentrate for autologous transplantation in minipigs. Characterization and osteogenic potential of mesenchymal stem cells.

    Science.gov (United States)

    Herten, M; Grassmann, J P; Sager, M; Benga, L; Fischer, J C; Jäger, M; Betsch, M; Wild, M; Hakimi, M; Jungbluth, P

    2013-01-01

    Autologous bone marrow plays an increasing role in the treatment of bone, cartilage and tendon healing disorders. Cell-based therapies display promising results in the support of local regeneration, especially therapies using intra-operative one-step treatments with autologous progenitor cells. In the present study, bone marrow-derived cells were concentrated in a point-of-care device and investigated for their mesenchymal stem cell (MSC) characteristics and their osteogenic potential. Bone marrow was harvested from the iliac crest of 16 minipigs. The mononucleated cells (MNC) were concentrated by gradient density centrifugation, cultivated, characterized by flow cytometry and stimulated into osteoblasts, adipocytes, and chondrocytes. Cell differentiation was investigated by histological and immunohistological staining of relevant lineage markers. The proliferation capacity was determined via colony forming units of fibroblast and of osteogenic alkaline-phosphatase-positive-cells. The MNC could be enriched 3.5-fold in nucleated cell concentrate in comparison to bone marrow. Flow cytometry analysis revealed a positive signal for the MSC markers. Cells could be differentiated into the three lines confirming the MSC character. The cellular osteogenic potential correlated significantly with the percentage of newly formed bone in vivo in a porcine metaphyseal long-bone defect model. This study demonstrates that bone marrow concentrate from minipigs display cells with MSC character and their osteogenic differentiation potential can be used for osseous defect repair in autologous transplantations.

  13. Collagen type I from bovine bone. Effect of animal age, bone anatomy and drying methodology on extraction yield, self-assembly, thermal behaviour and electrokinetic potential.

    Science.gov (United States)

    Ferraro, Vincenza; Gaillard-Martinie, Brigitte; Sayd, Thierry; Chambon, Christophe; Anton, Marc; Santé-Lhoutellier, Véronique

    2017-04-01

    Natural collagen is easily available from animal tissues such as bones. Main limitations reported in the use of natural collagen are heterogeneity and loss of integrity during recovery. However, its natural complexity, functionality and bioactivity still remain to be achieved through synthetic and recombinant ways. Variability of physicochemical properties of collagen extracted from bovine bone by acetic acid was then investigated taking into account endogenous and exogenous factors. Endogenous: bovine's bones age (4 and 7 years) and anatomy (femur and tibia); exogenous: thermal treatments (spray-drying and lyophilisation). Scanning electron microscopy, spectroscopy (EDS, FTIR, UV/Vis and CD), differential scanning calorimetry (DSC), centesimal composition, mass spectrometry, amino acids and zeta-potential analysis were used for the purpose. Age correlated negatively with yield of recovery and positively with minerals and proteoglycans content. Comparing the anatomy, higher yields were found for tibias, and higher stability of tibias collagen in solution was noticed. Whatever the age and the anatomy, collagens were able to renature and to self-assemble into tri-dimensional structures. Nonetheless thermal stability and kinetics of renaturation were different. Variability of natural collagen with bone age and anatomy, and drying methodology, may be a crucial advantage to conceive tailor-made applications in either the biological or technical sector. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. A new biphasic osteoinductive calcium composite material with a negative Zeta potential for bone augmentation

    Directory of Open Access Journals (Sweden)

    Maciejewski Oliver

    2009-06-01

    Full Text Available Abstract The aim of the present study was to analyze the osteogenic potential of a biphasic calcium composite material (BCC with a negative surface charge for maxillary sinus floor augmentation. In a 61 year old patient, the BCC material was used in a bilateral sinus floor augmentation procedure. Six months postoperative, a bone sample was taken from the augmented regions before two titanium implants were inserted at each side. We analyzed bone neoformation by histology, bone density by computed tomography, and measured the activity of voltage-activated calcium currents of osteoblasts and surface charge effects. Control orthopantomograms were carried out five months after implant insertion. The BCC was biocompatible and replaced by new mineralized bone after being resorbed completely. The material demonstrated a negative surface charge (negative Zeta potential which was found to be favorable for bone regeneration and osseointegration of dental implants.

  15. Stippled ribs - A potential pitfall in bone scan interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Fink-Bennett, D.; Johnson, J.

    1985-05-01

    A retrospective evaluation of 100 consecutive bone scans were performed to determine the incidence and clinical importance, if any, of increased uptake at the insertion of the iliocostalis thoracis portion of the erector spinae muscle group (rib stippling). The scans were performed two-three hours after the intravenous injection of 15 mCi of technetium-99m methylene diphosphonate. (Tc-99m MDP). Each patient had a standard whole body scan (scintillation camera with whole body imaging table) or a whole body tomographic scan (PhoCon). Rib stippling was deemed present if a focal area of increased Tc-99m MDP was identified within the posterior angle of three or more consecutive ribs. Seven of 100 (3 bilateral, 4 unilateral) patients demonstrated rib stippling. Foci intensity was less than the scapular tips, but greater than the adjacent ribs. No patient had a history of chest traumapain and/or an abnormal radiograph. Even though increased uptake within the posterior angle of the ribs is an uncommon finding (7%), its recognition as a normal bone scan finding is important to prevent bone scan misinterpretations. Its characteristic scintigraphic appearance and location should serve to differentiate it from the increased uptake of trauma and/or tumor.

  16. Development of an angiogenesis-promoting microvesicle-alginate-polycaprolactone composite graft for bone tissue engineering applications

    Directory of Open Access Journals (Sweden)

    Hui Xie

    2016-05-01

    Full Text Available One of the major challenges of bone tissue engineering applications is to construct a fully vascularized implant that can adapt to hypoxic environments in vivo. The incorporation of proangiogenic factors into scaffolds is a widely accepted method of achieving this goal. Recently, the proangiogenic potential of mesenchymal stem cell-derived microvesicles (MSC-MVs has been confirmed in several studies. In the present study, we incorporated MSC-MVs into alginate-polycaprolactone (PCL constructs that had previously been developed for bone tissue engineering applications, with the aim of promoting angiogenesis and bone regeneration. MSC-MVs were first isolated from the supernatant of rat bone marrow-derived MSCs and characterized by scanning electron microscopic, confocal microscopic, and flow cytometric analyses. The proangiogenic potential of MSC-MVs was demonstrated by the stimulation of tube formation of human umbilical vein endothelial cells in vitro. MSC-MVs and osteodifferentiated MSCs were then encapsulated with alginate and seeded onto porous three-dimensional printed PCL scaffolds. When combined with osteodifferentiated MSCs, the MV-alginate-PCL constructs enhanced vessel formation and tissue-engineered bone regeneration in a nude mouse subcutaneous bone formation model, as demonstrated by micro-computed tomographic, histological, and immunohistochemical analyses. This MV-alginate-PCL construct may offer a novel, proangiogenic, and cost-effective option for bone tissue engineering.

  17. Synthesis and Characterization of Protein-Conjugated Silver Nanoparticles/Silver Salt Loaded Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) Film for Prevention of Bacterial Infections and Potential Use in Bone Tissue Engineering Applications

    Science.gov (United States)

    Bakare, Rotimi Ayotunde

    Failure of orthopedic implants due to bacterial infection has been a major concern in bone tissue engineering. To this end, we have formulated a potential orthopedic implant made of naturally occurring biodegradable polymer, i.e. poly (3-hydroxylbutyrate-co-3-hydroxylvalerate) (PHBV), modified with BSA conjugated silver nanoparticles and or silver chloride. Upon release of Ag NPs and or Ag+ in the implant region, can promote aseptic environment by inhibition of bacteria growth and also support/maintain bone cell adhesion, growth, and proliferation. For formulating nanoparticles loaded PHBV scaffold, we exploit specific interaction between bovine serum albumin (BSA) of BSA capped silver nanoparticles and collagen of collagen immobilized PHBV scaffold. Therefore, the first part of this study dealt with synthesis and characterization of collagen immobilized PHBV film for loading of BSA stabilized silver (Ag/BSA) nanoparticles. Two different approaches were used to immobilize collagen on macroporous PHBV film. First approach uses thermal radical copolymerization with 2-hydroxyethylmethacrylate (HEMA), while the second approach uses aminolysis to functionalize macroporous PHBV film. Using collagen crosslinker, type I collagen was covalently grafted to formulate collagen immobilized PHEMA-g-PHBV and collagen immobilized NH2-PHBV films, respectively. Spectroscopic (FTIR, XPS), physical (SEM), and thermal (TGA) techniques were used to characterize the functionalized PHBV films. The Ag/BSA nanoparticles were then loaded on collagen immobilized PHBV films and untreated PHBV films. The concentration of nanoparticles loaded on PHBV film was determined by atomic absorption spectrometry and fluorescence spectroscopy. The amount of nanoparticles loaded on collagen immobilized PHBV film was found to be significantly greater than that on untreated PHBV film. The amount of Ag/BSA nanoparticles loaded on collagen immobilized PHBV film was found to depend on the concentration of Ag

  18. Application and Effect of Mobiletype-Bone Health Intervention in Korean Young Adult Women with Low Bone Mass: A Randomized Control Trial

    Directory of Open Access Journals (Sweden)

    Young-Joo Park, PhD, RN

    2017-03-01

    Conclusion: Although both experimental groups exhibited positive outcomes in regards to the promotion of bone health, this study did not show an additional effect of the mobile application on self-management ability for the promotion of bone health. Nonetheless, the SbFb application is very meaningful as it is the first application developed with the aim of improving women's bone health.

  19. Different methods of dentin processing for application in bone tissue engineering: A systematic review.

    Science.gov (United States)

    Tabatabaei, Fahimeh Sadat; Tatari, Saeed; Samadi, Ramin; Moharamzadeh, Keyvan

    2016-10-01

    Dentin has become an interesting potential biomaterial for tissue engineering of oral hard tissues. It can be used as a scaffold or as a source of growth factors in bone tissue engineering. Different forms of dentin have been studied for their potential use as bone substitutes. Here, we systematically review different methods of dentin preparation and the efficacy of processed dentin in bone tissue engineering. An electronic search was carried out in PubMed and Scopus databases for articles published from 2000 to 2016. Studies on dentin preparation for application in bone tissue engineering were selected. The initial search yielded a total of 1045 articles, of which 37 were finally selected. Review of studies showed that demineralization was the most commonly used dentin preparation process for use in tissue engineering. Dentin extract, dentin particles (tooth ash), freeze-dried dentin, and denatured dentin are others method of dentin preparation. Based on our literature review, we can conclude that preparation procedure and the size and shape of dentin particles play an important role in its osteoinductive and osteoconductive properties. Standardization of these methods is important to draw a conclusion in this regard. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2616-2627, 2016. © 2016 Wiley Periodicals, Inc.

  20. Ionization potentials some variations, implications and applications

    CERN Document Server

    Ahrens, L H

    1983-01-01

    Ionization Potentials: Some Variations, Implications and Applications covers several aspects of ionization potential that is a highly significant parameter in controlling the properties of electric discharge. Comprised of 17 chapters, the book covers topic relevant to ionization potentials, such as properties, concepts, and applications, in order to understand and fully comprehend all aspects of ionization potential. The opening chapter is a review of ionization potentials and a discussion of trends and features. The succeeding chapters then tackle complex topics such as the s and p electrons;

  1. [Clinical application of biological bone carrier in repair of long bone defect of femur].

    Science.gov (United States)

    Yao, L; Chen, J; Hu, X

    1997-05-01

    It is difficult to repair long defect of bone. Biological bone carrier (BBC) was one of the artifical bone substitutes. It was obtained from human or swine bone after a series of biochemical treatment. It had good histocompatibility. It had the same components and structure of bone, and its biological strength was samiliar to bone. In clinic, BBC was applied to repair of long defect of bone in two cases. The lengths of defect were 13 cm and 11 cm, respectively. After followed up for 2 to 3 years, it was found that the implanted BBC had been combined with the femur with new bone. It had the same metabolism and density as that of the normal bone.

  2. Fabrication and characterization of a novel carbon fiber-reinforced calcium phosphate silicate bone cement with potential osteo-inductivity

    International Nuclear Information System (INIS)

    Zheng, Jiangjiang; Xiao, Yu; Bao, Chongyun; Gong, Tianxing; Zhou, Shuxin; Troczynski, Tom; Yang, Quanzu; Xu, Xiaoming

    2016-01-01

    The repair of bone defects is still a pressing challenge in clinics. Injectable bone cement is regarded as a promising material to solve this problem because of its special self-setting property. Unfortunately, its poor mechanical conformability, unfavorable osteo-genesis ability and insufficient osteo-inductivity seriously limit its clinical application. In this study, novel experimental calcium phosphate silicate bone cement reinforced by carbon fibers (CCPSC) was fabricated and characterized. First, a compressive strength test and cell culture study were carried out. Then, the material was implanted into the femoral epiphysis of beagle dogs to further assess its osteo-conductivity using a micro-computed tomography scan and histological analysis. In addition, we implanted CCPSC into the beagles’ intramuscular pouches to perform an elementary investigation of its osteo-inductivity. The results showed that incorporation of carbon fibers significantly improved its mechanical properties. Meanwhile, CCPSC had better biocompatibility to activate cell adhesion as well as proliferation than poly-methyl methacrylate bone cement based on the cell culture study. Moreover, pronounced biodegradability and improved osteo-conductivity of CCPSC could be observed through the in vivo animal study. Finally, a small amount of osteoid was found at the heterotopic site one month after implantation which indicated potential osteo-inductivity of CCPSC. In conclusion, the novel CCPSC shows promise as a bioactive bone substitute in certain load-bearing circumstances. (paper)

  3. Corals and Their Potential Applications to Integrative Medicine

    Directory of Open Access Journals (Sweden)

    Edwin L. Cooper

    2014-01-01

    Full Text Available Over the last few years, we have pursued the use and exploitation of invertebrate immune systems, most notably their humoral products, to determine what effects their complex molecules might exert on humans, specifically their potential for therapeutic applications. This endeavor, called “bioprospecting,” is an emerging necessity for biomedical research. In order to treat the currently “untreatable,” or to discover more efficient treatment modalities, all options and potential sources must be exhausted so that we can provide the best care to patients, that is, proceed from forest and ocean ecosystems through the laboratory to the bedside. Here, we review current research findings that have yielded therapeutic benefits, particularly as derived from soft and hard corals. Several applications have already been demonstrated, including anti-inflammatory properties, anticancer properties, bone repair, and neurological benefits.

  4. Minerals and vitamins in bone health: the potential value of dietary enhancement.

    Science.gov (United States)

    Bonjour, Jean-Philippe; Guéguen, Léon; Palacios, Cristina; Shearer, Martin J; Weaver, Connie M

    2009-06-01

    Nutrition is important to bone health, and a number of minerals and vitamins have been identified as playing a potential role in the prevention of bone diseases, particularly osteoporosis. Despite this, there is currently no consensus on maximum levels to allow in food or as dietary supplements. The benefits of supplementation of populations at risk of osteoporosis with Ca and vitamin D are well established. Prolonged supplementation of Ca and vitamin D in elderly has been shown to prevent bone loss, and in some intervention studies to prevent fragility fractures. Although P is essential to bone health, the average intake is considered to be more than sufficient and supplementation could raise intake to adverse levels. The role of vitamin K in bone health is less well defined, though it may enhance the actions of Ca and vitamin D. Sr administered in pharmacological doses as the ranelate salt was shown to prevent fragility fractures in postmenopausal osteoporosis. However, there is no hard evidence that supplementation with Sr salts would be beneficial in the general population. Mg is a nutrient implicated in bone quality, but the benefit of supplementation via foodstuffs remains to be established. A consensus on dietary supplementation for bone health should balance the risks, for example, exposure of vulnerable populations to values close to maximal tolerated doses, against evidence for benefits from randomised clinical trials, such as those for Ca and vitamin D. Feedback from community studies should direct further investigations and help formulate a consensus on dietary supplementation for bone health.

  5. Bone cells in cultures on nanocarbon-based materials for potential bone tissue engineering: A review

    Czech Academy of Sciences Publication Activity Database

    Bačáková, Lucie; Kopová, Ivana; Staňková, Ľubica; Lišková, Jana; Vacík, Jiří; Lavrentiev, Vasyl; Kromka, Alexander; Potocký, Štěpán; Stránská, D.

    2014-01-01

    Roč. 211, č. 12 (2014), s. 2688-2702 ISSN 1862-6300 R&D Projects: GA ČR(CZ) GAP108/12/1168; GA ČR(CZ) GA14-04790S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) EE2.3.30.0025 Institutional support: RVO:67985823 ; RVO:68378271 ; RVO:61389005 Keywords : biocompatibility * bone implants * carbon * nanoparticles Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.616, year: 2014

  6. Bioactive glasses beyond bone and teeth: emerging applications in contact with soft tissues.

    Science.gov (United States)

    Miguez-Pacheco, Valentina; Hench, Larry L; Boccaccini, Aldo R

    2015-02-01

    The applications of bioactive glasses (BGs) have to a great extent been related to the replacement, regeneration and repair of hard tissues, such as bone and teeth, and there is an extensive bibliography documenting the role of BGs as bone replacement materials and in bone tissue engineering applications. Interestingly, many of the biochemical reactions arising from the contact of BGs with bodily fluids, in particular the local increase in concentration of various ions at the glass-tissue interface, are also relevant to mechanisms involved in soft tissue regeneration. An increasing number of studies report on the application of BGs in contact with soft tissues, aiming at exploiting the well-known bioactive properties of BGs in soft tissue regeneration and wound healing. This review focuses on research, sometimes involving preliminary in vitro studies but also in vivo evidence, that demonstrates the suitability of BGs in contact with tissues outside the skeletal system, which includes studies investigating vascularization, wound healing and cardiac, lung, nerve, gastrointestinal, urinary tract and laryngeal tissue repair using BGs in various forms of particulates, fibers and nanoparticles with and without polymer components. Potentially active mechanisms of interaction of BGs and soft tissues based on the surface bioreactivity of BGs and on biomechanical stimuli affecting the soft tissue-BG collagenous bonding are discussed based on results in the literature. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  7. Application of human amniotic mesenchymal cells as an allogeneic transplantation cell source in bone regenerative therapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsuno, Hiroaki [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Yoshida, Toshiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nogami, Makiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Orthopedic Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Koike, Chika; Okabe, Motonori [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Noto, Zenko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Arai, Naoya; Noguchi, Makoto [Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nikaido, Toshio, E-mail: tnikaido@med.u-toyama.ac.jp [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan)

    2012-12-01

    Autogenous mesenchymal stem cells (MSCs) have therapeutic applications in bone regenerative therapy due to their pluripotency. However, the ability of MSCs to proliferate and differentiate varies between donors. Furthermore, alternative sources of MSCs are required for patients with contraindications to autogenous cell therapy. The aim of this study was to evaluate the potential of mesenchymal cells from the human amniotic membrane (HAM) as a source of cells for allogeneic transplantation in bone regenerative therapy. Cells that retained a proliferative capacity of more than 50 population doubling level were distinguished from other HAM cells as HAM{alpha} cells and induced to osteogenic status-their in vivo osteogenesis was subsequently investigated in rats. It was found that HAM{alpha} cells were spindle shaped and were positive for MSC markers and negative for hematopoietic stem cell markers. Alkaline phosphatase activity and calcium deposition increased with osteogenic status of HAM{alpha} cells. The expression of osteocalcin mRNA was increased in HAM{alpha} cells cultured on calcium phosphate scaffolds. Moreover, xenografted HAM{alpha} cells remained viable and produced extracellular matrix for several weeks. Thus, this study suggests that human amniotic mesenchymal cells possess osteogenic differentiation potential and could be applied to allogeneic transplantation in bone regenerative therapy. - Highlights: Black-Right-Pointing-Pointer Human amniotic mesenchymal cells include cells (HAM{alpha} cells) that have the properties of MSCs. Black-Right-Pointing-Pointer HAM{alpha} cells have excellent osteogenic differentiation potential. Black-Right-Pointing-Pointer Osteogenic differentiation ability of HAM{alpha} was amplified by calcium phosphate scaffolds. Black-Right-Pointing-Pointer HAM{alpha} cells can be applicable to allogeneic cell transplantation in bone regenerative therapy.

  8. Physicochemical characterization of porcine bone-derived grafting material and comparison with bovine xenografts for dental applications.

    Science.gov (United States)

    Lee, Jung Heon; Yi, Gyu Sung; Lee, Jin Woong; Kim, Deug Joong

    2017-12-01

    The physicochemical properties of a xenograft are very important because they strongly influence the bone regeneration capabilities of the graft material. Even though porcine xenografts have many advantages, only a few porcine xenografts are commercially available, and most of their physicochemical characteristics have yet to be reported. Thus, in this work we aimed to investigate the physicochemical characteristics of a porcine bone grafting material and compare them with those of 2 commercially available bovine xenografts to assess the potential of xenogenic porcine bone graft materials for dental applications. We used various characterization techniques, such as scanning electron microscopy, the Brunauer-Emmett-Teller adsorption method, atomic force microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and others, to compare the physicochemical properties of xenografts of different origins. The porcine bone grafting material had relatively high porosity (78.4%) and a large average specific surface area (SSA; 69.9 m 2 /g), with high surface roughness (10-point average roughness, 4.47 µm) and sub-100-nm hydroxyapatite crystals on the surface. Moreover, this material presented a significant fraction of sub-100-nm pores, with negligible amounts of residual organic substances. Apart from some minor differences, the overall characteristics of the porcine bone grafting material were very similar to those of one of the bovine bone grafting material. However, many of these morphostructural properties were significantly different from the other bovine bone grafting material, which exhibited relatively smooth surface morphology with a porosity of 62.0% and an average SSA of 0.5 m 2 /g. Considering that both bovine bone grafting materials have been successfully used in oral surgery applications in the last few decades, this work shows that the porcine-derived grafting material possesses most of the key physiochemical characteristics required for its

  9. [Application of small freeze-drying allogeneic bone plots mixed with autologous bone graft in spinal fusion].

    Science.gov (United States)

    Tian, Changqing; Li, Zhenyu; Zhou, Wenyu; Zeng, Tenghui; Sun, Shiquan; Li, Baoxing

    2009-05-01

    To investigate the osteoblasts effect, complications and influencing factors in the application of small freeze-drying allogeneic bone plots mixed autologous bone fragments in spinal surgery, and to compare with autogenous bone graft. From January 2003 to January 2007, 515 cases of spinal injuries were treated. A total of 324 cases were treated with small freeze-drying allogeneic bone plots mixed with autologous bone grafts (group A), including 211 males and 113 females with an average age of 36 years (18-83 years). There were 182 cases of thoracolumbar vertebra fracture, 68 cases of lumbar spondylolisthesis, 47 cases of lumbar vertebral canal stenosis, 17 cases of cervical disc herniation, 5 cases of cervical spine fracture-dislocation and 5 cases of thoracolumbar vertebra tumor. The weight of bone graft was 10-60 g (mean 30 g). A total of 191 cases were treated with autogenous bone grafting (group B), including 135 males and 56 females with an average age of 32 years (23-78 years). There were 109 cases of thoracolumbar vertebra fracture, 23 cases of lumbar spondylolisthesis, 17 cases of lumbar vertebral canal stenosis, 19 cases of cervical disc herniation, and 23 cases of cervical spine fracture-dislocation. The weight of bone graft was 10-50 g (mean 25 g). In group A, effusion of wound increased in 4 cases and the result of bacterial culture was negative; effusion was absorbed after 2 weeks of local irrigation, drainage and cortin management. In group B, no obvious effusion was observed. The follow-up time was 10-36 months (mean 17.4 months) in group A and 8-36 months (mean 16.8 months) in group B. The bone healing was achieved in 308 cases within 4-10 months (mean 8.1 months) and in 184 cases within 4-10 months (mean 5.8 months), and the bone fusion rates were 95.06% and 96.34% in groups A and B, respectively. There was no significant difference in bone fusion rate between groups (P > 0.05). According to Mankin and Komender evaluation standard, the response

  10. Ethylene oxide gas sterilization does not reduce the osteoinductive potential of demineralized bone in rats

    DEFF Research Database (Denmark)

    Solheim, E; Pinholt, E M; Bang, G

    1995-01-01

    It has been shown that different sterilization procedures of demineralized bone may influence its osteoinductive properties. The aim of this study was to evaluate the effect of ethylene oxide sterilization for 1, 3, and 6 hours on the osteoinductive potential of allogeneic demineralized bone...... and qualitatively by light microscopy of histological sections. One-way analyses of variance at the 0.05 level revealed no significant difference in strontium 85 uptake of the different groups, and no qualitative differences in osteoinduction could be detected by light microscopy. Ossicles consisting of bone...

  11. Potential applications of high temperature helium

    International Nuclear Information System (INIS)

    Schleicher, R.W. Jr.; Kennedy, A.J.

    1992-09-01

    This paper discusses the DOE MHTGR-SC program's recent activity to improve the economics of the MHTGR without sacrificing safety performance and two potential applications of high temperature helium, the MHTGR gas turbine plant and a process heat application for methanol production from coal

  12. Processing and characterization of diatom nanoparticles and microparticles as potential source of silicon for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Le, Thi Duy Hanh [Department of Industrial Engineering, University of Trento, Trento (Italy); BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Trento (Italy); Bonani, Walter [Department of Industrial Engineering, University of Trento, Trento (Italy); BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Trento (Italy); Interuniversity Consortium for Science and Technology of Materials, Trento Research Unit, Trento (Italy); Speranza, Giorgio [Center for Materials and Microsystems, PAM-SE, Fondazione Bruno Kessler, Trento (Italy); Sglavo, Vincenzo; Ceccato, Riccardo [Department of Industrial Engineering, University of Trento, Trento (Italy); Maniglio, Devid; Motta, Antonella [Department of Industrial Engineering, University of Trento, Trento (Italy); BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Trento (Italy); Interuniversity Consortium for Science and Technology of Materials, Trento Research Unit, Trento (Italy); Migliaresi, Claudio, E-mail: claudio.migliaresi@unitn.it [Department of Industrial Engineering, University of Trento, Trento (Italy); BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Trento (Italy); Interuniversity Consortium for Science and Technology of Materials, Trento Research Unit, Trento (Italy)

    2016-02-01

    Silicon plays an important role in bone formation and maintenance, improving osteoblast cell function and inducing mineralization. Often, bone deformation and long bone abnormalities have been associated with silica/silicon deficiency. Diatomite, a natural deposit of diatom skeleton, is a cheap and abundant source of biogenic silica. The aim of the present study is to validate the potential of diatom particles derived from diatom skeletons as silicon-donor materials for bone tissue engineering applications. Raw diatomite (RD) and calcined diatomite (CD) powders were purified by acid treatments, and diatom microparticles (MPs) and nanoparticles (NPs) were produced by fragmentation of purified diatoms under alkaline conditions. The influence of processing on the surface chemical composition of purified diatomites was evaluated by X-ray photoelectron spectroscopy (XPS). Diatoms NPs were also characterized in terms of morphology and size distribution by transmission electron microscopy (TEM) and Dynamic light scattering (DLS), while diatom MPs morphology was analyzed by scanning electron microscopy (SEM). Surface area and microporosity of the diatom particles were evaluated by nitrogen physisorption methods. Release of silicon ions from diatom-derived particles was demonstrated using inductively coupled plasma optical emission spectrometry (ICP/OES); furthermore, silicon release kinetic was found to be influenced by diatomite purification method and particle size. Diatom-derived microparticles (MPs) and nanoparticles (NPs) showed limited or no cytotoxic effect in vitro depending on the administration conditions. - Highlights: • Diatomite is a natural source of silica and has a potential as silicon-donor for bone regenerative applications. • Diatom particles derived from purified diatom skeletons were prepared by fragmentation under extreme alkaline condition. • Dissolution of diatom particles derived from diatom skeletons in DI water depend on purification method

  13. Processing and characterization of diatom nanoparticles and microparticles as potential source of silicon for bone tissue engineering

    International Nuclear Information System (INIS)

    Le, Thi Duy Hanh; Bonani, Walter; Speranza, Giorgio; Sglavo, Vincenzo; Ceccato, Riccardo; Maniglio, Devid; Motta, Antonella; Migliaresi, Claudio

    2016-01-01

    Silicon plays an important role in bone formation and maintenance, improving osteoblast cell function and inducing mineralization. Often, bone deformation and long bone abnormalities have been associated with silica/silicon deficiency. Diatomite, a natural deposit of diatom skeleton, is a cheap and abundant source of biogenic silica. The aim of the present study is to validate the potential of diatom particles derived from diatom skeletons as silicon-donor materials for bone tissue engineering applications. Raw diatomite (RD) and calcined diatomite (CD) powders were purified by acid treatments, and diatom microparticles (MPs) and nanoparticles (NPs) were produced by fragmentation of purified diatoms under alkaline conditions. The influence of processing on the surface chemical composition of purified diatomites was evaluated by X-ray photoelectron spectroscopy (XPS). Diatoms NPs were also characterized in terms of morphology and size distribution by transmission electron microscopy (TEM) and Dynamic light scattering (DLS), while diatom MPs morphology was analyzed by scanning electron microscopy (SEM). Surface area and microporosity of the diatom particles were evaluated by nitrogen physisorption methods. Release of silicon ions from diatom-derived particles was demonstrated using inductively coupled plasma optical emission spectrometry (ICP/OES); furthermore, silicon release kinetic was found to be influenced by diatomite purification method and particle size. Diatom-derived microparticles (MPs) and nanoparticles (NPs) showed limited or no cytotoxic effect in vitro depending on the administration conditions. - Highlights: • Diatomite is a natural source of silica and has a potential as silicon-donor for bone regenerative applications. • Diatom particles derived from purified diatom skeletons were prepared by fragmentation under extreme alkaline condition. • Dissolution of diatom particles derived from diatom skeletons in DI water depend on purification method

  14. Bone Degeneration, Inflammation and Secondary Complications of Arthritis: Potential Targets and their Natural Inhibitors.

    Science.gov (United States)

    Hemshekhar, Mahadevappa; Thushara, Ram M; Kumar, Somanathapura K Naveen; Paul, Manoj; Sundaram, Mahalingam S; Kemparaju, Kempaiah; Girish, Kesturu S

    2018-01-01

    Arthritis is marked by joint deterioration that affects articular cartilage and subchondral bone. Though cartilage degradation does the major damage during arthritis, subsequent bone degeneration cannot be neglected. Recent progress in arthritis research has identified the clinical importance of bone erosion in destructive arthritis. Studies have showed the key role played by osteoclasts and receptor activator of nuclear factor kappaB ligand (RANKL) signaling in bone erosion. Cathepsins and tartrate resistant acid phosphatase (TRAP) are considered key enzymatic factors contributing to bone erosion. Further, reactive oxygen species (ROS) formed at the ruffled border of osteoclasts also causes bone resorption and matrix degradation. Besides, severe inflammation during arthritis induces bone erosion by aiding in Ca2+ removal and activating osteoclastogenesis. The inflammatory cytokines and ROS influence osteoclast differentiation by regulating osteoclast-lineage cells or by acting on other cells to regulate the expression of RANKL and osteoprotegerin (OPG). The enhanced production of pro-inflammatory cytokines and ROS in arthritis stimulates tissue injury by means of oxidative damage leading to vital organ damage and synovial and circulatory cell apoptosis. Thus, blocking enzymatic and non-enzymatic factors responsible for bone erosion and inflammation is considered a prime strategy in the management of arthritis. In this review we provide an overview of the mechanisms of bone erosion, inflammation and associated oxidative stress/damage during arthritis perpetuation along with shedding light on potential targets. The article also describes the possible natural therapeutic agents that could prevent bone loss and inflammation, and related secondary complications of arthritis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Scaffold of chitosan-sodium alginate and hydroxyapatite with application potential for bone regeneration; Scaffold de quitosana-alginato de sodio e hidroxiapatita com potencial de aplicacao para regeneracao ossea

    Energy Technology Data Exchange (ETDEWEB)

    Rebelo, Marcia de A.; Alves, Thais F.R.; Lopes, Francielly C.C.N; Oliveira Junior, Jose Martins de; Pontes, Katiusca S.; Fogaca, Bruna A.C.; Chaud, Marco V., E-mail: marco.chaud@prof.uniso.br [Universidade de Sorocaba (LABNUS/UNISO), Sorocaba, SP (Brazil). Laboratorio de Biomateriais e Nanotecnologia

    2015-07-01

    Scaffold for organic tissue regeneration are architectural, three-dimensional, porous, biocompatible and biodegradable devices. The first challenges to be met in the development of these devices to mimic the biomechanical properties of the target tissue. The aim of this study was to develop and to characterize scaffolds composed of chitosan (Ch), sodium alginate (SA), hydroxyapatite (HA). The scaffolds were obtained by lyophilization. HA has been incorporated into the polymer dispersion in Ch-AS concentration of 20 and 60%. The mechanical properties of the scaffold were determined by tensile and compression tests. Swelling capacity was assessed in the presence of simulated saliva, purified water, HCl 0.01M, NaOH 0.01M. The calcium content was quantified using fluorescence X-rays. Analysis of the results indicates that the Qt-AS-HA-60% scaffold obtained by lyophilization meets promising properties for bone tissue regeneration. (author)

  16. Osteoinductive potential of a novel biphasic calcium phosphate bone graft in comparison with autographs, xenografts, and DFDBA.

    Science.gov (United States)

    Miron, Richard J; Sculean, Anton; Shuang, Yang; Bosshardt, Dieter D; Gruber, Reinhard; Buser, Daniel; Chandad, Fatiha; Zhang, Yufeng

    2016-06-01

    Since the original description of osteoinduction in the early 20th century, the study and development of innovative biomaterials has emerged. Recently, novel synthetic bone grafts have been reported with potential to form ectopic bone in vivo. However, their full characterization in comparison with other leading bone grafts has not been investigated. The aim of this study was to determine the osteoinductive potential of bone grafts by comparing autogenous bone grafts, demineralized freeze-dried bone allografts (DFDBA), a commonly utilized natural bone mineral (NBM) from bovine origin (Bio-Oss), and a newly developed biphasic calcium phosphate (BCP). Grafts were compared in vitro for their ability to stimulate bone marrow stromal cell (BMSC) migration, proliferation, and differentiation as assessed by quantitative real-time PCR for genes coding for bone markers including Runx2, collagen I, and osteocalcin. Furthermore, bone grafts were implanted in the calf muscle of 12 beagle dogs to determine their potential to form ectopic bone in vivo. The in vitro results demonstrate that both autografts and DFDBA show potential for cell recruitment, whereas only autografts and BCP demonstrated the ability to differentiate BMSCs toward the osteoblast lineage. The in vivo ectopic bone model demonstrated that while NBM particles were not osteoinductive and autogenous bone grafts were resorbed quickly in vivo, ectopic bone formation was reported in DFDBA and in synthetic BCP grafts. The modifications in nanotopography and chemical composition of the newly developed BCP bone grafts significantly promoted ectopic bone formation confirming their osteoinductive potential. In conclusion, the results from this study provide evidence that synthetic bone grafts not only serve as a three-dimensional scaffold but are also able to promote osteoinduction. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. [Development and application of bone-anchored hearing aid].

    Science.gov (United States)

    Liu, Yupeng; Yang, Jun

    2013-01-01

    Bone-anchored hearing aid is a hearing assisting technology that raise the hearing level via bone conduct and is also the only implantable hearing assisting device working by bone conduct. Because of the superior performance and simple process of implantation, it brings gospel to the patients who are not fitting the air conducting hearing devices. This article is a review of bone-anchored hearing aid from 6 aspects, including history, principle, indication, consulting, surgery and complication.

  18. Osteogenic potential of the human bone morphogenetic protein 2 gene activated nanobone putty.

    Science.gov (United States)

    Tian, Xiao-bin; Sun, Li; Yang, Shu-hua; Zhang, Yu-kun; Hu, Ru-yin; Fu, De-hao

    2008-04-20

    Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 (hBMP2) gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects. Twenty four Kunming mice were randomly divided into two groups. The nanobone putty + hBMP2 plasmid was injected into the right thigh muscle pouches of the mice (experiment side). The nanobone putty + blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 (control side 1) or group 2 (control side 2), respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups: Group A, nanobone putty + hBMP2 plasmid; Group B, putty + blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation. The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The new bone

  19. Fluorescent Bisphosphonate and Carboxyphosphonate Probes: A Versatile Imaging Toolkit for Applications in Bone Biology and Biomedicine.

    Science.gov (United States)

    Sun, Shuting; Błażewska, Katarzyna M; Kadina, Anastasia P; Kashemirov, Boris A; Duan, Xuchen; Triffitt, James T; Dunford, James E; Russell, R Graham G; Ebetino, Frank H; Roelofs, Anke J; Coxon, Fraser P; Lundy, Mark W; McKenna, Charles E

    2016-02-17

    A bone imaging toolkit of 21 fluorescent probes with variable spectroscopic properties, bone mineral binding affinities, and antiprenylation activities has been created, including a novel linking strategy. The linking chemistry allows attachment of a diverse selection of dyes fluorescent in the visible to near-infrared range to any of the three clinically important heterocyclic bisphosphonate bone drugs (risedronate, zoledronate, and minodronate or their analogues). The resultant suite of conjugates offers multiple options to "mix and match" parent drug structure, fluorescence emission wavelength, relative bone affinity, and presence or absence of antiprenylation activity, for bone-related imaging applications.

  20. Application of extracorporeal shock wave on bone: preliminary report.

    Science.gov (United States)

    Ikeda, K; Tomita, K; Takayama, K

    1999-11-01

    We have studied the effect of extracorporeal shock waves (ESW) on bone. ESW emitted by the new powerful generator provides three to six times greater energy than a common lithotriptor. Because the ESW causes fracture of rabbit femurs and induces new bone formation, we have called this treatment as ESWIB (ESW-induced bone formation). The purpose of this study is to confirm the effect of ESWIB on a canine model, which is more similar to clinical cases, and to apply ESWIB on nonunion of clinical cases. In our basic research, ESWIB was applied on six canine femurs as follows: group I with 100, 500, 1,000 shots and group II with 100, 500, 1,000 shots. A femur was extracted immediately after ESWIB in group I and 2 months after ESWIB in group II. Blood tests, including blood cell counts and blood chemistry studies, were performed before and after ESWIB in group II. In our clinical research, we applied ESWIB to six patients of delayed or nonunion of the fracture. The sites of the ESWIB application were three tibiae, one radius, one femur, and one humerus. Average age of the patients, the period from the previous surgery, and the period until fusion was achieved were 38.6 years, 14.0 months, and 4.3 months, respectively. In our basic research, group I, 500 or more shots caused periosteum detachment. In addition, small fractures of the inner surface of the cortex were observed. However, gross fracture with displacement was not observed. In group II, 500 or more shots caused callus formation beneath the detached periosteum. Subcutaneous hemorrhage was seen in all dogs, and the degree of bleeding was directly proportional to the number of the shots. The blood was absorbed within a week. The level of serum creatine kinase was significantly high 2 days after ESWIB, but it recovered in a week. In our clinical research, four of the patients achieved union without any complications except mild subcutaneous bleeding. We predict that ESWIB will be one of the tactics for treatment of

  1. Application of Computer-Assisted Design and Manufacturing-Fabricated Artificial Bone in the Reconstruction of Craniofacial Bone Defects.

    Science.gov (United States)

    Liang, Weiqiang; Yao, Yuanyuan; Huang, Zixian; Chen, Yuhong; Ji, Chenyang; Zhang, Jinming

    2016-07-01

    The purpose of this study was to evaluate the clinical application of individual craniofacial bone fabrications using computer-assisted design (CAD)-computer-assisted manufacturing technology for the reconstruction of craniofacial bone defects. A total of 8 patients diagnosed with craniofacial bone defects were enrolled in this study between May 2007 and August 2010. After computed tomography scans were obtained, the patients were fitted with artificial bone that was created using CAD software, rapid prototyping technology, and epoxy-methyl acrylate resin and hydroxyapatite materials. The fabrication was fixed to the defect area with titanium screws, and soft tissue defects were repaired if necessary. The fabrications were precisely fixed to the defect areas, and all wounds healed well without any serious complications except for 1 case with intraoral incision dehiscence, which required further treatment. Postoperative curative effects were retrospectively observed after 6 to 48 months, acceptable anatomic and cosmetic outcomes were obtained, and no rejections or other complications occurred. The use of CAD-computer-assisted manufacturing technology-assisted epoxy-methyl acrylate resin and hydroxyapatite composite artificial bone to treat patients with craniofacial bone defects could enable the precise reconstruction of these defects and obtain good anatomic and cosmetic outcomes. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Osteoblasts and their applications in bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Rupani A

    2012-05-01

    Full Text Available Asha Rupani1, Richard Balint2, Sarah H Cartmell1,21Institute of Science and Technology in Medicine, Keele University, Hartshill, Stoke-on-Trent, UK; 2Materials Science Centre, The University of Manchester, Manchester, UKAbstract: Tissue engineering is an emerging therapy that offers a new solution to patients suffering from bone loss. It utilizes cells derived from such sources as a patient's own bone or bone marrow, which are laboratory-isolated, grown (so they multiply in number, and placed onto a degradable material, or scaffold, that has mechanical/chemical properties appropriate to the bone section that it is replacing. The cells plus the scaffold are then grown in a container, or bioreactor, which is necessary as it provides the correct environment required for the cells to proliferate, differentiate, and to produce extracellular matrix. The following review focuses on the use of osteoblasts for bone tissue engineering.Keywords: osteoblast, bone, tissue engineering, regenerative medicine, orthopaedic

  3. Potential biomedical applications of marine algae.

    Science.gov (United States)

    Wang, Hui-Min David; Li, Xiao-Chun; Lee, Duu-Jong; Chang, Jo-Shu

    2017-11-01

    Functional components extracted from algal biomass are widely used as dietary and health supplements with a variety of applications in food science and technology. In contrast, the applications of algae in dermal-related products have received much less attention, despite that algae also possess high potential for the uses in anti-infection, anti-aging, skin-whitening, and skin tumor treatments. This review, therefore, focuses on integrating studies on algae pertinent to human skin care, health and therapy. The active compounds in algae related to human skin treatments are mentioned and the possible mechanisms involved are described. The main purpose of this review is to identify serviceable algae functions in skin treatments to facilitate practical applications in this high-potential area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Chondrogenic potential of bone marrow–derived mesenchymal stem cells on a novel, auricular-shaped, nanocomposite scaffold

    Directory of Open Access Journals (Sweden)

    Kavi H Patel

    2013-12-01

    Full Text Available Reconstruction of the human auricle remains a challenge to plastic surgeons, and current approaches are not ideal. Tissue engineering provides a promising alternative. This study aims to evaluate the chondrogenic potential of bone marrow–derived mesenchymal stem cells on a novel, auricular-shaped polymer. The proposed polyhedral oligomeric silsesquioxane-modified poly(hexanolactone/carbonateurethane/urea nanocomposite polymer has already been transplanted in patients as the world’s first synthetic trachea, tear duct and vascular bypass graft. The nanocomposite scaffold was fabricated via a coagulation/salt-leaching method and shaped into an auricle. Adult bone marrow–derived mesenchymal stem cells were isolated, cultured and seeded onto the scaffold. On day 21, samples were sent for scanning electron microscopy, histology and immunofluorescence to assess for neocartilage formation. Cell viability assay confirmed cytocompatability and normal patterns of cellular growth at 7, 14 and 21 days after culture. This study demonstrates the potential of a novel polyhedral oligomeric silsesquioxane-modified poly(hexanolactone/carbonateurethane/urea scaffold for culturing bone marrow–derived mesenchymal stem cells in chondrogenic medium to produce an auricular-shaped construct. This is supported by scanning electron microscopy, histological and immunofluorescence analysis revealing markers of chondrogenesis including collagen type II, SOX-9, glycosaminoglycan and elastin. To the best of our knowledge, this is the first report of stem cell application on an auricular-shaped scaffold for tissue engineering purposes. Although many obstacles remain in producing a functional auricle, this is a promising step forward.

  5. Bone substitute biomaterials

    CERN Document Server

    Mallick, K

    2014-01-01

    Bone substitute biomaterials are fundamental to the biomedical sector, and have recently benefitted from extensive research and technological advances aimed at minimizing failure rates and reducing the need for further surgery. This book reviews these developments, with a particular focus on the desirable properties for bone substitute materials and their potential to encourage bone repair and regeneration. Part I covers the principles of bone substitute biomaterials for medical applications. One chapter reviews the quantification of bone mechanics at the whole-bone, micro-scale, and non-scale levels, while others discuss biomineralization, osteoductivization, materials to fill bone defects, and bioresorbable materials. Part II focuses on biomaterials as scaffolds and implants, including multi-functional scaffolds, bioceramics, and titanium-based foams. Finally, Part III reviews further materials with the potential to encourage bone repair and regeneration, including cartilage grafts, chitosan, inorganic poly...

  6. Advanced bredigite-containing magnesium-matrix composites for biodegradable bone implant applications.

    Science.gov (United States)

    Dezfuli, Sina Naddaf; Huan, Zhiguang; Mol, Arjan; Leeflang, Sander; Chang, Jiang; Zhou, Jie

    2017-10-01

    The present research was aimed at developing magnesium-matrix composites that could allow effective control over their physiochemical and mechanical responses when in contact with physiological solutions. A biodegradable, bioactive ceramic - bredigite was chosen as the reinforcing phase in the composites, based on the hypothesis that the silicon- and magnesium-containing ceramic could protect magnesium from fast corrosion and at the same time stimulate cell proliferation. Methods to prepare composites with integrated microstructures - a prerequisite to achieve controlled biodegradation were developed. A systematic experimental approach was taken in order to elucidate the in vitro biodegradation mechanisms and kinetics of the composites. It was found that the composites with 20-40% homogenously dispersed bredigite particles, prepared from powders, could indeed significantly decrease the degradation rate of magnesium by up to 24 times. Slow degradation of the composites resulted in the retention of the mechanical integrity of the composites within the strength range of cortical bone after 12days of immersion in a cell culture medium. Cell attachment, cytotoxicity and bioactivity tests confirmed the stimulatory effects of bredigite embedded in the composites on the attachment, viability and differentiation of bone marrow stromal cells. Thus, the multiple benefits of adding bredigite to magnesium in enhancing degradation behavior, mechanical properties, biocompatibility and bioactivity were obtained. The results from this research showed the excellent potential of the bredigite-containing composites for bone implant applications, thus warranting further in vitro and in vivo research. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Properties and potential of bone marrow mesenchymal stromal cells from children with hematologic diseases.

    Science.gov (United States)

    Dimitriou, H; Linardakis, E; Martimianaki, G; Stiakaki, E; Perdikogianni, C H; Charbord, P; Kalmanti, M

    2008-01-01

    Mesenchymal stromal cells (MSC) have become the focus of cellular therapeutics but little is known regarding bone marrow (BM) MSC derived from children. As MSC constitute part of BM stroma, we examined their properties in children with hematologic diseases. BM MSC from children with non-malignant hematologic disorders and acute lymphoblastic leukemia (ALL) were isolated and expanded. MSC were immunophenotypically characterized and their functional characteristics were assessed by CFU-F assay and cell doubling time calculation. Their ability for trilineage differentiation was verified by molecular and histochemical methods. Apoptosis was evaluated and clonal analysis was performed. MSC were isolated from BM of all groups. They acquired the mesenchymal-related markers from the first passage, with a simultaneous decrease of hematopoietic markers. A very low percentage of apoptotic cells was detected in all passages. The proliferative and clonogenic capacity did not differ among groups, with the exception of ALL at diagnosis, in which they were defective. Histochemical and molecular analysis of differentiated MSC yielded characteristics for adipocytes, osteoblasts and chondrocytes. Clonal analysis in a number of BM samples revealed a highly heterogeneous population of cells within each clone. MSC from BM of children with hematologic disorders, with the exception of ALL at diagnosis, can be isolated in sufficient number and quality to serve as a potential source for clinical applications.

  8. Biocomposites from (Anadara granosa) shells waste for bone material applications

    Science.gov (United States)

    Saharudin, S. H.; Shariffuddin, J. H.; Nordin, N. I. A. A.

    2017-10-01

    The overall objective for this study is to determine the effect of biopolymer types and ratio on producing biocomposites derived from cockle (Anadara granosa) shells waste. In this study, two types of biopolymer were used i.e. sodium alginate and carboxymethyl cellulose. These biocomposites are meant for bone material applications. The processes involved in producing the biocomposites were pre-treatment of the cockle shells, formation of CaCO3 in aragonite form and finally the synthesis of biocomposites. All samples have undergone physicochemical and mechanical analyses to determine their crystallinity, purity, functional group, surface morphology, elemental compounds and compressive strength using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Electron Dispersive X-ray Analysis (EDX) and Universal testing machine (UTM). The CaCO3-biocomposites have been prepared using different ratio of biopolymer and different types of biopolymers. The physicochemical properties of the biocomposites are not affected by the ratio and types of biopolymers. Yet, the ratio and types of biopolymers have influenced the mechanical properties of biocomposites. The biocomposite with lesser amount of biopolymer has denser structure and greater mechanical strength. Comparison between types of polymers revealed that biocomposite with carboxymethyl cellulose has greater mechanical strength compared to biocomposite with sodium alginate.

  9. Dry bone histology : technicalities, diagnostic value and new applications

    NARCIS (Netherlands)

    Boer, Hans Henk de

    2014-01-01

    This thesis presents an easy, rapid and inexpensive supplement to the well-known method of Maat et al. (2001). This new method allows for the histochemical staining of dry bone material, enhancing the visibility of important hallmarks of dry bone histomorphology. In addition, this thesis provides a

  10. Criteria for palliation of bone metastases - Clinical applications

    International Nuclear Information System (INIS)

    2008-02-01

    Bone metastases are a frequent complication of cancer. It is estimated that they arise in 14-70% of all tumour patients, while it was reported that they occur in 70-85% patients in autopsy material. Although they may arise from any primary malignant tumour, certain tumours such as breast, prostate, lung, thyroid, kidney and myeloma have a predilection for a spread to bone. Bone metastases frequently cause pain, but there are also clinical situations with bone metastases causing no pain at all. The overall importance of the problem of bone metastases is well recognized by the fact that each year hundreds of thousands of cancer patients develop bone metastases. For example, more than 100 000 new patients develop this condition in the United States of America, although the prevalence is estimated to be double the number of new cases. While it is virtually unknown how many cancer patients in the developing countries develop bone metastases, it is not unrealistic to expect that these figures largely surpass those coming from the developed countries. The reason is simply that more patients in the developing countries are diagnosed as having locally advanced or metastatic cancer that will eventually widely disseminate, including bone metastasis as well. Furthermore, at least some of the cancer patients may survive prolonged periods of time. They can also develop earlier and more severe symptoms than patients harbouring other types (locations) of metastases, emphasizing the importance of the overall problem of painful bone metastases. In addition, there is a big socioeconomic problem of bone metastasis, burdening health care systems worldwide, while having continuous adverse psychological effect on both patients and their families. The management of patients with metastatic bone pain must be a multidisciplinary approach and includes the use of analgesia, radiotherapy, surgery, chemotherapy, hormone treatment, radioisotopes and bisphosphonates. Analgesia, with non

  11. Criteria for palliation of bone metastases - Clinical applications

    International Nuclear Information System (INIS)

    2007-04-01

    Bone metastases are a frequent complication of cancer. It is estimated that they arise in 14-70% of all tumour patients, while it was reported that they occur in 70-85% patients in autopsy material. Although they may arise from any primary malignant tumour, certain tumours such as breast, prostate, lung, thyroid, kidney and myeloma have a predilection for a spread to bone. Bone metastases frequently cause pain, but there are also clinical situations with bone metastases causing no pain at all. The overall importance of the problem of bone metastases is well recognized by the fact that each year hundreds of thousands of cancer patients develop bone metastases. For example, more than 100 000 new patients develop this condition in the United States of America, although the prevalence is estimated to be double the number of new cases. While it is virtually unknown how many cancer patients in the developing countries develop bone metastases, it is not unrealistic to expect that these figures largely surpass those coming from the developed countries. The reason is simply that more patients in the developing countries are diagnosed as having locally advanced or metastatic cancer that will eventually widely disseminate, including bone metastasis as well. Furthermore, at least some of the cancer patients may survive prolonged periods of time. They can also develop earlier and more severe symptoms than patients harbouring other types (locations) of metastases, emphasizing the importance of the overall problem of painful bone metastases. In addition, there is a big socioeconomic problem of bone metastasis, burdening health care systems worldwide, while having continuous adverse psychological effect on both patients and their families. The management of patients with metastatic bone pain must be a multidisciplinary approach and includes the use of analgesia, radiotherapy, surgery, chemotherapy, hormone treatment, radioisotopes and bisphosphonates. Analgesia, with non

  12. Reduction of Dietary Acid Load as a Potential Countermeasure for Bone Loss Associated with Spaceflight

    Science.gov (United States)

    Zwart, S. R.; Watts, S. M.; Sams, C. F.; Whitson, P. A.; Smith, S. M.

    2006-01-01

    In several studies we tested the concepts that diet can alter acid-base balance and that reducing the dietary acid load has a positive effect on maintenance of bone. In study 1, (n = 11, 60-90 d bed rest), the renal acid load of the diet was estimated from its chemical composition, and was positively correlated with urinary markers of bone resorption (P less than 0.05); that is, the greater the acid load, the greater the excretion of bone resorption markers. In study 2, in males (n = 8, 30 d bed rest), an estimate of the ratio of nonvolatile acid precursors to base precursors in the diet was positively correlated (P less than 0.05) with markers of bone resorption. In study 3, for 28 d subjects received either a placebo (n = 6) or an essential amino acid supplement (n = 7) that included methionine, a known acid precursor. During bed rest (28 d), urinary calcium was greater than baseline levels in the supplemented group but not the control group (P less than 0.05), and in the supplemented group, urinary pH decreased (P less than 0.05). In study 4, less bone resorption occurred in space crew members who received potassium citrate (n = 6) during spaceflight of 4-6 months than in crew members who received placebo or were not in the study (n = 8) (P less than 0.05). Reducing acid load has the potential to mitigate increased bone resorption during spaceflight, and may serve as a bone loss countermeasure.

  13. Crosstalk between bone niche and immune system: osteoimmunology signaling as a potential target for cancer treatment.

    Science.gov (United States)

    Criscitiello, Carmen; Viale, Giulia; Gelao, Lucia; Esposito, Angela; De Laurentiis, Michele; De Placido, Sabino; Santangelo, Michele; Goldhirsch, Aron; Curigliano, Giuseppe

    2015-02-01

    There is a well recognized link between the bone and the immune system and in recent years there has been a major effort to elucidate the multiple functions of the molecules expressed in both bone and immune cells. Several molecules that were initially identified and studied in the immune system have been shown to have essential functions also in the bone. An interdisciplinary field embracing immune and bone biology has been brought together and called "osteoimmunology". The co-regulation of the skeletal and immune systems strikingly exemplifies the extreme complexity of such an interaction. Their interdependency must be considered in designing therapeutic approaches for either of the two systems. In other words, it is necessary to think of the osteoimmune system as a complex physiological unit. Denosumab was originally introduced to specifically target bone resorption, but it is now under evaluation for its effect on the long term immune response. Similarly, our current and still growing knowledge of the intimate link between the immune system and bone will be beneficial for the safety of drugs targeting either of these integrated systems. Given the large number of molecules exerting functions on both the skeletal and immune systems, osteoimmunological understanding is becoming increasingly important. Both bone and immune systems are frequently disrupted in cancer; and they may be crucial in regulating tumor growth and progression. Some therapies - such as bisphosphonates and receptor activator of NF-κB ligand (RANKL) targeted drugs - that aim at reducing pathologic osteolysis in cancer may interact with the immune system, thus providing potential favorable effects on survival. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Diffusion of protease into meat & bone meal for solubility improvement and potential inactivation of the BSE prion.

    Directory of Open Access Journals (Sweden)

    Brian A Coll

    2007-02-01

    Full Text Available Government-imposed feed bans have created a need for new applications for meat & bone meal (MBM. Many potential new applications require MBM protein to be both soluble and free of infectious prion. Treatment with protease is generally effective in reducing insoluble, thermally-denatured proteins to soluble peptides. It has been reported in the literature that certain proteases, including Versazyme, are able to degrade infectious prions in a system where the prions are readily accessible to proteolytic attack. Prions distributed within MBM, however, may conceivably be protected from proteases.The overall rate of proteolytic MBM digestion depends greatly on whether the protease can penetrate deep within individual particles, or if the protease can only act near the surface of the particle. This research examined the barriers to the diffusion of Versazyme into particles of MBM. Confocal microscopy demonstrated differences in the density distributions between the bone and the soft tissue particles of MBM. By tracking the diffusion of fluorescently labeled Versazyme through individual particles, it was found that bone particles show full Versazyme penetration within 30 minutes, while penetration of soft tissue particles can take up to four hours, depending on the particle's diameter. From the variety of normal proteins comprising MBM, a specific protein was chosen to serve as a prion surrogate based on characteristics including size, solubility, distribution and abundance. This surrogate was used to measure the effect of several factors on Versazyme diffusion.Results showed that surrogate distributed in bone particles was more susceptible to degradation than that in soft tissue particles. Three factors controllable by unit operations in an industrial-scale process were also tested. It was found that removing the lipid content and hydrating MBM prior to incubation both significantly increased the rate of surrogate degradation. In a test of particle

  15. Physical-chemical characterization of bovine bone ash for evaluating its potential agricultural use

    Directory of Open Access Journals (Sweden)

    Eduardo Pacca Luna Mattar

    2014-03-01

    Full Text Available The manufacturing of bovine bone ash is a low cost and easy production process which can be adopted for making good use of animal residues, in locations without infrastructure, such as the family production units. This study aimed at describing the manufacturing process of bone ash and characterizing the physical and chemical parameters of the resulting material for organic fertilization. The experiment was performed with three replications, being evaluated the bovine bone ash manufacturing process yield, as well as its density, water retention capacity, pH of the resulting material after burning and contents of total calcium, calcium soluble in water, total phosphorus and phosphorus soluble in citric acid and in ammonium citrate. The process resulted in an average yield of 24.4% and the bovine bone ash presented 33.07% of total calcium, 15.6% of total phosphorus, 10.4% of phosphorus soluble in citric acid, pH of 9.94, density of 0.89 g cm-3 and water retention capacity of 73.3%. The bovine bone ash showed promising characteristics, with potential for being used as source of phosphorus and calcium in the organic fertilization process.

  16. The relationship between Computed Tomography and DXA results: A potential bias in Bone Mineral Density assessment

    Directory of Open Access Journals (Sweden)

    Andrey Bokov

    2017-06-01

    Full Text Available Background It has been reported that the results of the lumbar spine bone mineral density assessment can be strongly biased by degenerative changes. However, the reported data remains controversial and a potential bias has not been assessed. Aims To evaluate the relationships between the results of DXA and CT with the assessment of potential bias related to the influence of different structures. Methods This is a cross-sectional study and 25 patients were enrolled. Using DXA scan, Bone Mineral density (BMD (g/cm2 was calculated from 100 vertebra from the lumbar spine. Out of all the CT measurements, a mean radiodensity in HU (Hounsfield Units for cancellous bone and total vertebra body, a mean square and radiodensity of vertebra pedicles and facet were calculated. Results Linear regression analysis demonstrated a strong correlation between BMD measured by DXA and CT data. Multiple correlation coefficient of model accounts for 0.8093, r2=0.6550, p<0.0001. Parameters that have significant relationships with the results of DXA were: a product of facet joints radiodensity and mean square on axial images (B= 0.000003379, p<0.0001 and total vertebral body radiodensity B=0.0016395253, p=0.0201. Beta coefficients for those variables accounted for 0.6729 and 0.3037 respectively. Conclusion The results of the bone mineral density assessment of the lumbar spine using DXA, can be strongly influenced by facet joints condition, especially in cases of degenerative changes. The results of BMD, provided by DXA, are partly relevant to vertebral body bone quality assessment and irrelevant to the characteristics of bone in pedicles. This means that the prognostic value of the DXA measurement results might be limited in relation to predicting low energy vertebra fracture and implant stability.

  17. Potential of Starch Nanocomposites for Biomedical Applications

    Science.gov (United States)

    Zakaria, N. H.; Muhammad, N.; Abdullah, M. M. A. B.

    2017-06-01

    In recent years, the development of biodegradable materials from renewable sources based on polymeric biomaterials have grown rapidly due to increase environmental concerns and the shortage of petroleum sources. In this regard, naturally renewable polymers such as starch has shown great potential as environmental friendly materials. Besides, the unique properties of starch such as biodegradable and non-toxic, biocompatible and solubility make them useful for a various biomedical applications. Regardless of their unique properties, starch materials are known to have limitations in term of poor processability, low mechanical properties, poor long term stability and high water sensitivity. In order to overcome these limitations, the incorporation of nano size fillers into starch materials (nanocomposites) has been introduced. This review aims to give an overview about structure and characteristics of starch, modification of starch by nanocomposites and their potential for biomedical applications.

  18. Extremozymes: A Potential Source for Industrial Applications.

    Science.gov (United States)

    Dumorné, Kelly; Córdova, David Camacho; Astorga-Eló, Marcia; Renganathan, Prabhaharan

    2017-04-28

    Extremophilic microorganisms have established a diversity of molecular strategies in order to survive in extreme conditions. Biocatalysts isolated by these organisms are termed extremozymes, and possess extraordinary properties of salt allowance, thermostability, and cold adaptivity. Extremozymes are very resistant to extreme conditions owing to their great solidity, and they pose new opportunities for biocatalysis and biotransformations, as well as for the development of the economy and new line of research, through their application. Thermophilic proteins, piezophilic proteins, acidophilic proteins, and halophilic proteins have been studied during the last few years. Amylases, proteases, lipases, pullulanases, cellulases, chitinases, xylanases, pectinases, isomerases, esterases, and dehydrogenases have great potential application for biotechnology, such as in agricultural, chemical, biomedical, and biotechnological processes. The study of extremozymes and their main applications have emerged during recent years.

  19. Comparison of the osteogenic potentials of autologous cultured osteoblasts and mesenchymal stem cells loaded onto allogeneic cancellous bone granules.

    Science.gov (United States)

    Kim, Seok-Jung; Chung, Yang-Guk; Lee, Yun-Kyoung; Oh, Il-Whan; Kim, Yong-Sik; Moon, Young-Seok

    2012-02-01

    We compared the bone regeneration potentials of autologous cultured osteoblasts and of bone-marrow-derived autologous MSCs in combination with allogeneic cancellous bone granules in a rabbit radial defect model. Radial shaft defects over 15 mm were made in 26 New Zealand white rabbits. The animals underwent insertion of allogeneic cancellous bone granules containing autologous osteoblasts into right-side defects (the experimental group) and of allogeneic cancellous bone granules with autologous MSCs into left-side defects (the control group). To quantitatively assess bone regeneration, radiographic evaluations as well as BMD and BMC measurements were performed 3, 6, 9 and 12 weeks post-implantation and histology as well as micro-CT image analysis were performed at 6 and 12 weeks. Radiographic evaluations 3 weeks post-implantation showed that the experimental group had a higher mean bone quantity index (p bone volume and surface area than the control sides (p bone formation in the experimental group. This in vivo study demonstrates that a combination of autologous osteoblasts and small-sized, allogeneic cancellous bone granules leads to more rapid bone regeneration than autologous MSCs and small-sized, allogeneic cancellous bone granules.

  20. Myogenic Differentiation Potential of Mesenchymal Stem Cells Derived from Fetal Bovine Bone Marrow.

    Science.gov (United States)

    Okamura, Lucas Hidenori; Cordero, Paloma; Palomino, Jaime; Parraguez, Victor Hugo; Torres, Cristian Gabriel; Peralta, Oscar Alejandro

    2018-01-02

    The myogenic potential of bovine fetal MSC (bfMSC) derived from bone marrow (BM) remains unknown; despite its potential application for the study of myogenesis and its implications for livestock production. In the present study, three protocols for in vitro myogenic differentiation of bfMSC based on the use of DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5-Aza), myoblast-secreted factor Galectin-1 (Gal-1), and myoblast culture medium SkGM-2 BulletKit were used. Plastic-adherent bfMSC were isolated from fetal BM collected from abattoir-derived fetuses. Post-thaw viability analyses detected 85.6% bfMSC negative for propidium iodine (PI). Levels of muscle regulatory factors (MRF) MYF5, MYF6, MYOD, and DES mRNA were higher (P < 0.05) in bfMSC cultured under 100 µM of 5-Aza compared to 1 and 10 µM. Treatment of bfMSC with 10 µM of 5-Aza resulted in down-regulation of MYOD mRNA (Days 7 to 21) and up-regulation of MYF6 (Day 7), MYF5, and DES mRNA (Day 21). Gal-1 and SkGM-2 BulletKit induced sequential down-regulation of early MRF (MYF5) and up-regulation of intermediate (MYOD) and late MRF (DES) mRNA. Moreover, DES and MYF5 were immunodetected in differentiated bfMSC. In conclusion, protocols evaluated in bfMSC induced progress into myogenic differentiation until certain extent evidenced by changes in MRF gene expression.

  1. APPLICATION OF A BIODEGRADABLE MATERIAL FOR BONE REPLACEMENT IN TRAUMATOLOGY

    Directory of Open Access Journals (Sweden)

    T. V. Druzhinina

    2014-01-01

    Full Text Available 20 men (medium age (31.5 ± 13.5 years were studied. All patients underwent arthroscopic auditing plastic anterior cruciate ligament of the knee. Osteoregeneration dynamics were determined by biochemical testing of blood serum and X-ray computed tomography (CT of the fracture in 1–4 months after surgery. As a result, an estimation of the bone tissue reparative regeneration according to CT data in 10 patients with a defect of the patella, treated with the material is provided. The obtained results of the clinical study indicate the reparative effect of the biodegradable material for bone replacing on bone regeneration

  2. Hydroxyapatite-hybridized chitosan/chitin whisker bionanocomposite fibers for bone tissue engineering applications.

    Science.gov (United States)

    Pangon, Autchara; Saesoo, Somsak; Saengkrit, Nattika; Ruktanonchai, Uracha; Intasanta, Varol

    2016-06-25

    Biomimetic nanofibrous scaffolds derived from natural biopolymers for bone tissue engineering applications require good mechanical and biological performances including biomineralization. The present work proposes the utility of chitin whisker (CTWK) to enhance mechanical properties of chitosan/poly(vinyl alcohol) (CS/PVA) nanofibers and to offer osteoblast cell growth with hydroxyapatite (HA) mineralization. By using diacid as a solvent, electrospun CS/PVA nanofibrous membranes containing CTWK can be easily obtained. The dimension stability of nanofibrous CS/PVA/CTWK bionanocomposite is further controlled by exposing to glutaraldehyde vapor. The nanofibrous membranes obtained allow mineralization of HA in concentrated simulated body fluid resulting in an improvement of Young's modulus and tensile strength. The CTWK combined with HA in bionanocomposite is a key to promote osteoblast cell adhesion and proliferation. The present work, for the first time, demonstrates the use of CTWKs for bionanocomposite fibers of chitosan and its hydroxyapatite biomineralization with the function in osteoblast cell culture. These hydroxyapatite-hybridized CS/PVA/CTWK bionanocomposite fibers (CS/PVA/CTWK-HA) offer a great potential for bone tissue engineering applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Osteogenic potential of effective bone engineering using dental pulp stem cells, bone marrow stem cells, and periosteal cells for osseointegration of dental implants.

    Science.gov (United States)

    Ito, Kenji; Yamada, Yoichi; Nakamura, Sayaka; Ueda, Minoru

    2011-01-01

    The aim of this comparative study was to investigate cell-based effective bone engineering and the correlation between the osseointegration of dental implants and tissue-engineered bone using dental pulp stem cells (DPSC), bone marrow stem cells (BMSC), and periosteal cells (PC). The first molar and all premolars were extracted from the mandibles of three dogs, and in each dog, six bone defects (three on each side) were prepared with a 10-mm-diameter trephine bur after 4 weeks. Different materials were implanted in the defects and the sites were allowed to heal. The experimental groups were as follows: (1) dog DPSC and platelet-rich plasma (PRP) (dDPSC/PRP), (2) dog BMSC and PRP (dBMSC/PRP), (3) dog PC and PRP (dPC/PRP), and (4) control (defect only). Eight weeks later, dental implants were placed in the defects. After another 8 weeks, the amount of bone regeneration was assessed by histologic and histomorphometric analyses (bone-implant contact). The mean bone-implant contact values were 66.7% ± 3.6% for group 1 (dDPSC/PRP), 62.5% ± 3.1% for group 2 (dBMSC/PRP), 39.4% ± 2.4% for group 3 (dPC/PRP), and 30.3% ± 2.6% for the control group. DPSC showed the highest osteogenic potential and may be a useful cell source for tissue-engineered bone around dental implants.

  4. Does size difference in allogeneic cancellous bone granules loaded with differentiated autologous cultured osteoblasts affect osteogenic potential?

    Science.gov (United States)

    Lee, Sang-Uk; Chung, Yang-Guk; Kim, Seok-Jung; Oh, Il-Hoan; Kim, Yong-Sik; Ju, Sung-Hun

    2014-02-01

    We study the efficacy of bone regeneration by using two differently sized allogeneic cancellous bone granules loaded with autologous cultured osteoblasts in a rabbit model. Critical-sized bone defects of the radial shaft were made in 40 New Zealand White rabbits. Small allogeneic bone granules (150-300 μm in diameter) loaded with cultured differentiated autologous osteoblasts were implanted into one forearm (SBG group) and large bone granules (500-710 μm) loaded with osteoblasts were implanted into the forearm of the other side (LBG group). Radiographic evaluations were performed at 3, 6, 9 and 12 weeks and histology and micro-CT image analysis were carried out at 6 and 12 weeks post-implantation. On radiographic evaluation, the LBG group showed a higher bone quantity index at 3 and 6 weeks post-implantation (P bone volume and surface area than the SBG group at 6 weeks (P bone formation and maturation in the SBG group. Thus, the two differently sized allogeneic bone granules loaded with co-cultured autologous osteoblasts show no differences in the amount of bone regeneration, although the SBG group exhibits faster progression of bone regeneration and remodeling. This method might therefore provide benefits, such as a short healing time and easy application in an injectable form, in a clinical setting.

  5. Strontium doped injectable bone cement for potential drug delivery applications.

    Science.gov (United States)

    Taha, Ali; Akram, Muhammad; Jawad, Zaidoon; Alshemary, Ammar Z; Hussain, Rafaqat

    2017-11-01

    Microwave assisted wet precipitation method was used to synthesize calcium deficient strontium doped β-tricalcium phosphate (Sr-βTCP) with a chemical formula of Ca 2.96-x Sr x (PO 4 ) 2 . Sr-βTCP was reacted with monocalcium phosphate monohydrate [Ca(H 2 PO 4 ) 2 .H 2 O, MCPM] in presence of water to furnish corresponding Sr containing brushite cement (Sr-Brc). The samples were characterized by using X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). Strontium content in the prepared samples was determined by using inductively coupled plasma optical emission spectrometry (ICP-OES). The effect of Sr 2+ ions on the structural, mechanical, setting properties and drug release of the cement is reported. Incorporation of Sr 2+ ions improved the injectability, setting time and mechanical properties of the Brc. The release profiles of antibiotics incorporated in Brc and Sr-Brc confirmed that the Sr incorporation into the Brc results in the efficient release of the antibiotics from the cement. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Silver doped resorbable tricalcium phosphate scaffolds for bone graft applications.

    Science.gov (United States)

    Hoover, Sean; Tarafder, Solaiman; Bandyopadhyay, Amit; Bose, Susmita

    2017-10-01

    Bone graft procedures, in particular maxillofacial repair, account for half of the orthopedic procedures done in the US each year. Infection is a major issue in surgery, and should be of primary concern when engineering biomaterials. Silver is of renewed importance today, as it has the ability to potentiate antibiotics against resistant bacterial strains. In order to reduce long term infection risks, it is necessary for the scaffold to maintain a silver ion release for the length of the healing process. In this study, silver doped porous β-tricalcium phosphate (β-TCP) scaffolds were engineered using liquid porogen based method with the goal of meeting these requirements. Silver was added to the β-TCP at three different dopant levels: 0.5wt% Ag 2 O, 1wt% Ag 2 O and 2wt% Ag 2 O. Immersion in pH5 acetate buffer over a 60day period resulted in a total cumulative ion release between 32 and 54μM for dense control scaffolds, and between 80 and 90μM for porous scaffolds. Porosity increased the dissolution rate of the scaffolds by a factor of 2. Human osteoblast cell lines were grown on the scaffolds to measure cytotoxicity and cell proliferation. Porosity increased osteoconduction by doubling the cell growth, and there was no significant cytotoxic effect even for the 2wt% Ag 2 O, as cells were observed on all the samples. Our results showed that silver can be released over a long period without compromising the biocompatibility of the scaffolds. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. BONES WITH BIOCERAMICS

    Directory of Open Access Journals (Sweden)

    Wijianto Wijianto

    2017-01-01

    Full Text Available This paper discuss about ceramics in application as bone implant. Bioceramics for instance Hydroxyapatite, usually is abbreviated with HA or HAp, is a mineral that is very good physical properties as bone replacement in human body. To produce Hydroxyapatite, coating process is used which have good potential as they can exploit the biocompatible and bone bonding properties of the ceramic. There are many advantages and disadvantages of bioceramics as bone implant. Advantages of hydroxyapatite as bone implant are rapidly integrated into the human body, and is most interesting property that will bond to bone forming indistinguishable unions. On contrary, disadvantages of hydroxyapatite as bone implant are poor mechanical properties (in particular fatigue properties mean that hydroxyapatite cannot be used in bulk form for load bearing applications such as orthopaedics and poor adhesion between the calcium phosphate coating and the material implant will occur.

  8. Potential Role of Bone Marrow Mesenchymal Stem Cells in Obstructive Sleep Apnea

    Science.gov (United States)

    Carreras, Alba; Almendros, Isaac; Farré, Ramon

    2011-01-01

    Obstructive sleep apnea syndrome (OSA) is a prevalent disease caused by increased collapsibility of the upper airway. OSA induces oxidative stress, inflammation and endothelial dysfunction, with important clinical consequences such as neurocognitive alterations and cardiovascular diseases. Although it has been shown that bone marrow-derived stem cells play a protective and reparative function in several diseases involving inflammatory processes and endothelial dysfunction, the data currently available on the potential role of adult stem cells in OSA are scarce. The present review presents recent data on the potential role of bone marrow-derived mesenchymal stem cells (MSC) in OSA. The results obtained in animal models that realistically mimic the events characterizing this sleep breathing disorder strongly support the notion that MSC are mobilized in circulating blood and then activated to play an anti-inflammatory role in OSA. PMID:24298333

  9. Chondrogenic potential of mesenchymal stromal cells derived from equine bone marrow and umbilical cord blood

    DEFF Research Database (Denmark)

    Berg, Lise Charlotte; Koch, Thomas Gadegaard; Heerkens, T.

    2009-01-01

    including bone marrow and umbilical cord blood. The objective of this study was to provide an in vitro comparison of the chondrogenic potential in MSC derived from adult bone marrow (BM-MSC) and umbilical cord blood (CB-MSC). Results: MSC from both sources produced tissue with cartilage-like morphology...... CB- and BM-MSC pellets. Protein concentration of cartilage-derived retinoic acid sensitive protein was higher in culture medium from CB- than BM-MSC pellets. Conclusion: CB-MSC and BM-MSC were both capable of producting hyaline-like cartilage in vitro. Howeverm, in this study the MSC from umbilical...... cord blood appeared to have more chondrogenic potential than the BM-MSC based on the cells tested and parameters measured....

  10. POTENTIAL APPLICATION OF NANOMETALS IN ENVIRONMENTAL PROTECTION

    Directory of Open Access Journals (Sweden)

    Dagmara Malina

    2017-02-01

    Full Text Available In recent years, great interest in metallic nanoparticles has been observed, both because of their unlimited application possibilities, and also because of the unusual biological, chemical and physical features. It is expected that developments in nanotechnology will become the main promoter of scientific and technological innovations in the coming decades. Searching for a new and safe alternative to chemical pesticides, high hopes are associated with nanotechnology development. Particularly useful may be preparations containing nanoscale metal particles with strong antimicrobial properties. Importantly, safe and non-toxic for the plant components of biological origin may be used in nanoparticles synthesis. This article is a description of the potential applications of nanomaterials in environmental protection, which may become the basis for developing of new protection plant products with antimicrobial properties relative to plant pathogens and non-toxic to higher organisms.

  11. Mesenchymal Stem Cells in Bone Tissue Regeneration and Application to Bone Healing

    Czech Academy of Sciences Publication Activity Database

    Crha, M.; Nečas, A.; Srnec, R.; Janovec, J.; Raušer, P.; Urbanová, L.; Plánka, L.; Jančář, J.; Amler, Evžen

    2009-01-01

    Roč. 78, č. 4 (2009), s. 635-642 ISSN 0001-7213 R&D Projects: GA MŠk 2B06130; GA AV ČR IAA500390702 Institutional research plan: CEZ:AV0Z50390703 Keywords : tissue engineering * biomaterials * segmental bone lesion Subject RIV: BO - Biophysics Impact factor: 0.403, year: 2009

  12. Potential aerospace applications of high temperature superconductors

    Science.gov (United States)

    Selim, Raouf

    1994-12-01

    The recent discovery of High Temperature Superconductors (HTS) with superconducting transition temperature, T(sub c), above the boiling point of liquid nitrogen has opened the door for using these materials in new and practical applications. These materials have zero resistance to electric current, have the capability of carrying large currents and as such have the potential to be used in high magnetic field applications. One of the space applications that can use superconductors is electromagnetic launch of payloads to low-earth-orbit. An electromagnetic gun-type launcher can be used in small payload systems that are launched at very high velocity, while sled-type magnetically levitated launcher can be used to launch larger payloads at smaller velocities. Both types of launchers are being studied by NASA and the aerospace industry. The use of superconductors will be essential in any of these types of launchers in order to produce the large magnetic fields required to obtain large thrust forces. Low Temperature Superconductor (LTS) technology is mature enough and can be easily integrated in such systems. As for the HTS, many leading companies are currently producing HTS coils and magnets that potentially can be mass-produced for these launchers. It seems that designing and building a small-scale electromagnetic launcher is the next logical step toward seriously considering this method for launching payloads into low-earth-orbit. A second potential application is the use of HTS to build sensitive portable devices for the use in Non Destructive Evaluation (NDE). Superconducting Quantum Interference Devices (SQUID's) are the most sensitive instruments for measuring changes in magnetic flux. By using HTS in SQUID's, one will be able to design a portable unit that uses liquid nitrogen or a cryocooler pump to explore the use of gradiometers or magnetometers to detect deep cracks or corrosion in structures. A third use is the replacement of Infra-Red (IR) sensor leads on

  13. Vibration Energy Harvesting Potential for Turbomachinery Applications

    Directory of Open Access Journals (Sweden)

    Adrian STOICESCU

    2018-03-01

    Full Text Available The vibration energy harvesting process represents one of the research directions for increasing power efficiency of electric systems, increasing instrumentation nodes autonomy in hard to reach locations and decreasing total system mass by eliminating cables and higher-power adapters. Research based on the possibility of converting vibration energy into useful electric energy is used to evaluate the potential of its use on turbomachinery applications. Aspects such as the structure and characteristics of piezoelectric generators, harvesting networks, their setup and optimization, are considered. Finally, performance test results are shown using piezoelectric systems on a turbine engine.

  14. Potential commercial applications of centrifuge technology

    International Nuclear Information System (INIS)

    1985-08-01

    As part of an effort to prevent the loss of and maximize the use of unique developments of the centrifuge program, this document identifies and briefly describes unclassified technologies potentially available for transfer. In addition, this document presents a preliminary plan for action needed to carry out the transfer activity. Continuing efforts will provide additional descriptions of technologies which have applications that are not as apparent or as obvious as those presented here. Declassification of some of the program information, now classified as restricted data, would permit the descriptions of additional technologies which have significant commercial potential. The following are major areas of technology where transfer opportunities exist: biomedical; separation; motors and control systems; materials; vacuum; dynamics and balancing; and diagnostics and instrumentation

  15. Functional outcome following treatment of segmental skeletal defects of the forearm bones by Ilizarov application.

    Science.gov (United States)

    El-Mowafi, Hani; Elalfi, Barakat; Wasfi, Khaled

    2005-04-01

    Managing a segmental skeletal defect is a challenge, even more so if the combination of local infection with bone defect exacerbates the problem and provides an even more negative prognosis. Several techniques have been tried, among which skeletal allografts, autologous cortical or cancellous bone graft and vascularised bone graft, each with its limitation and success. In this study, we report our results with the Ilizarov method of bone transport to overcome bone defects of forearm bones due to infection. This series included 16 patients with bone defects of forearm bones, following either debridement of osteomylitis or infected nonunion. The mean time from injury to the Ilizarov procedure was 11.7 months. The mean number of operative procedures before application of the Ilizarov device was 3.4. The mean length of the defects after debridement was 6.4 cm. Monofocal osteotomy was performed. The mean external fixation index, distraction index and maturation index were 41.5 days/cm, 19.8 days/ cm, and 21.7 days/cm respectively. The mean time in the frame was 8.9 months. The mean total duration of treatment was 11.4 months. There were 14 complications in 11 patients including pin-track infection, premature consolidation, delayed union at the docking site and refracture. Ilizarov's technique of bone transport is an ideal solution for a large skeletal defect in spite of the high incidence of associated complications.

  16. Development of Collagen/Demineralized Bone Powder Scaffolds and Periosteum-Derived Cells for Bone Tissue Engineering Application

    Directory of Open Access Journals (Sweden)

    Wilairat Leeanansaksiri

    2013-01-01

    Full Text Available The aim of this study was to investigate physical and biological properties of collagen (COL and demineralized bone powder (DBP scaffolds for bone tissue engineering. DBP was prepared and divided into three groups, based on various particle sizes: 75–125 µm, 125–250 µm, and 250–500 µm. DBP was homogeneously mixed with type I collagen and three-dimensional scaffolds were constructed, applying chemical crosslinking and lyophilization. Upon culture with human periosteum-derived cells (PD cells, osteogenic differentiation of PD cells was investigated using alkaline phosphatase (ALP activity and calcium assay kits. The physical properties of the COL/DBP scaffolds were obviously different from COL scaffolds, irrespective of the size of DBP. In addition, PD cells cultured with COL scaffolds showed significantly higher cell adhesion and proliferation than those with COL/DBP scaffolds. In contrast, COL/DBP scaffolds exhibited greater osteoinductive potential than COL scaffolds. The PD cells with COL/DBP scaffolds possessed higher ALP activity than those with COL scaffolds. PD cells cultured with COL/DBP scaffolds with 250–500 mm particle size yielded the maximum calcium deposition. In conclusion, PD cells cultured on the scaffolds could exhibit osteoinductive potential. The composite scaffold of COL/DBP with 250–500 mm particle size could be considered a potential bone tissue engineering implant.

  17. Activation of dimeric glucocorticoid receptors in osteoclast progenitors potentiates RANKL induced mature osteoclast bone resorbing activity.

    Science.gov (United States)

    Conaway, H Herschel; Henning, Petra; Lie, Anita; Tuckermann, Jan; Lerner, Ulf H

    2016-12-01

    Glucocorticoid (GC) therapy is the greatest risk factor for secondary osteoporosis. Pathogenic mechanisms involve an initial increase in bone resorption followed by decreased bone formation. To gain a better understanding of the resorptive activity of GCs, we have used mouse bone marrow macrophages (BMM) to determine if GCs can directly modulate RANKL stimulated osteoclast formation and/or activity. In agreement with previous studies, experiments performed in plastic wells showed that GCs (dexamethasone, hydrocortisone, and prednisolone) inhibited osteoclast number and size during the initial phases of RANKL stimulated osteoclastogenesis; however, in prolonged cultures, decreased apoptosis was observed and escape from GC induced inhibition occurred with an enhanced number of osteoclasts formed, many with an increased area. When BMM cells were seeded on bone slices, GCs robustly enhanced RANKL stimulated formation of resorption pits and release of CTX without affecting the number or size of osteoclasts formed and with no effect on apoptosis. Stimulation of pit formation was not associated with increased life span of osteoclasts or an effect on mRNA expression of several osteoclastic or osteoclastogenic genes. The potentiation of RANKL induced CTX release by dexamethasone was significantly less in BMM cells from mice with conditional knockout of the osteoclastic glucocorticoid receptor and completely absent in cells from GR dim mice, which carry a point mutation in one dimerizing interface of the GC receptor. These data suggest that: 1. Plastic is a poor medium to use for studying direct effects of GCs on osteoclasts 2. GCs can enhance bone resorption without decreasing apoptosis, and 3. A direct enhancement of RANKL mediated resorption is stimulated by the dimeric GC-receptor. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Assessment of age and sex by means of DXA bone densitometry: application in forensic anthropology.

    Science.gov (United States)

    Castillo, Rafael Fernández; Ruiz, Maria del Carmen López

    2011-06-15

    Today we are witnessing a genuine revolution in diagnostic imaging techniques. Dual X-ray absorptiometry (DEXA) quantifies bone mineral density (BMD) and bone mineral content (BMC). This technique has rarely been used in Forensic Anthropology, although its practical application has been demonstrated by various authors. In this article, we look into the conduct of bone mineral density in the femoral neck, the trochanter, the intertrochanter, the proximal femur and Ward's triangle, in relation to anthropometric age and sex parameters. The research was carried out on 70 persons - 38 men and 32 women - and the results obtained show significant correlations between bone mineral density measurements and anthropometric values. The research demonstrates bone mineral density to be a useful technique for sex and age data in forensic anthropology, particularly in the measurements observed in the Ward's triangle area. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  19. 3D-Printed Scaffolds and Biomaterials: Review of Alveolar Bone Augmentation and Periodontal Regeneration Applications

    Directory of Open Access Journals (Sweden)

    Farah Asa’ad

    2016-01-01

    Full Text Available To ensure a successful dental implant therapy, the presence of adequate vertical and horizontal alveolar bone is fundamental. However, an insufficient amount of alveolar ridge in both dimensions is often encountered in dental practice due to the consequences of oral diseases and tooth loss. Although postextraction socket preservation has been adopted to lessen the need for such invasive approaches, it utilizes bone grafting materials, which have limitations that could negatively affect the quality of bone formation. To overcome the drawbacks of routinely employed grafting materials, bone graft substitutes such as 3D scaffolds have been recently investigated in the dental field. In this review, we highlight different biomaterials suitable for 3D scaffold fabrication, with a focus on “3D-printed” ones as bone graft substitutes that might be convenient for various applications related to implant therapy. We also briefly discuss their possible adoption for periodontal regeneration.

  20. 3D-Printed Scaffolds and Biomaterials: Review of Alveolar Bone Augmentation and Periodontal Regeneration Applications

    Science.gov (United States)

    Asa'ad, Farah; Giannì, Aldo Bruno; Giannobile, William V.; Rasperini, Giulio

    2016-01-01

    To ensure a successful dental implant therapy, the presence of adequate vertical and horizontal alveolar bone is fundamental. However, an insufficient amount of alveolar ridge in both dimensions is often encountered in dental practice due to the consequences of oral diseases and tooth loss. Although postextraction socket preservation has been adopted to lessen the need for such invasive approaches, it utilizes bone grafting materials, which have limitations that could negatively affect the quality of bone formation. To overcome the drawbacks of routinely employed grafting materials, bone graft substitutes such as 3D scaffolds have been recently investigated in the dental field. In this review, we highlight different biomaterials suitable for 3D scaffold fabrication, with a focus on “3D-printed” ones as bone graft substitutes that might be convenient for various applications related to implant therapy. We also briefly discuss their possible adoption for periodontal regeneration. PMID:27366149

  1. Marine Bioactives and Potential Application in Sports

    Directory of Open Access Journals (Sweden)

    Maria Alessandra Gammone

    2014-04-01

    Full Text Available An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP, such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB, macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports.

  2. Marine bioactives and potential application in sports.

    Science.gov (United States)

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D'Orazio, Nicolantonio

    2014-04-30

    An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports.

  3. Marine Bioactives and Potential Application in Sports

    Science.gov (United States)

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D’Orazio, Nicolantonio

    2014-01-01

    An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports. PMID:24796298

  4. Fabrication of porous bioceramics for bone tissue applications using luffa cylindrical fibres (LCF as template

    Directory of Open Access Journals (Sweden)

    Mazen Alshaaer

    2017-03-01

    Full Text Available Three-dimensionally ordered macroporous biomaterials containing hydroxyapatite were synthesized using natural luffa cylindrical fibres (with diameter of 100–400 µm as templates. The preliminary evaluation of this novel method for production of porous bioceramics showed promising potential applications in bone tissue engineering. The produced bioceramics were subjected to microstructural, physical, mechanical, and in vitro characterisation. Mercury intrusion porosimetry, supported by SEM analysis, showed the presence of bimodal porosity (smaller pores with diameters of 10 to 30 µm and cylindrical macropores with diameters from 100 to 400 µm and 60% of the interconnected porosity. These porous calcium phosphate ceramics proved to be bioactive and exhibited mechanical properties comparable to those of natural spongy bones with compressive strength up to 3 MPa and elastic modulus in compression around 0.05 GPa. In vitro characterization of the porous ceramics showed cells attaching to the apatite crystals that make up the scaffold matrix. Cell adhesion resulted in elongated and highly stretched cells within the macropores with focal adhesion points on the scaffolds. Moreover, the cells adhered to the calcium phosphate cement (CPC and developed cytoplasmic extensions as shown by SEM imagery. Their proliferation in the scaffolds in culture demonstrates that the scaffold architecture is suitable for Mesenchymal stem cells seeding and growth.

  5. Evaluation of bone thickness around the mental foramen for potential fixation of a bone-borne functional appliance: a computer tomography scan study.

    Science.gov (United States)

    Al-Kalaly, Abdullah A; Wong, Ricky W K; Cheung, Lim K; Purkayastha, Shimanto K; Schätzle, Marc; Rabie, A Bakr M

    2010-11-01

    A mandible bone-borne Herbst appliance (MBBHA) would avoid the proclination of the lower incisors that occurs with any teeth-borne functional appliance. But mapping of the bone characteristics at potential fixation areas around the mental foramen has not been carried out so far. The aim of this computer tomographic (CT) study was to evaluate bone thickness at specific positions around the mental foramen. CT scans of 60 randomly chosen adult Hong Kong Chinese subjects (mean age 28 ± 6.3 years) were used to measure the bi-cortical bone thickness in the mandible in the mental foramen area. The thickness of buccal and lingual cortical and cancellous bone was assessed at the following locations: 10 mm (A10 mm) and 5 mm (A5 mm) anterior, 10 mm (P10 mm) and 5 mm (P5 mm) posterior, and 5 mm (Inf5 mm) below the mental foramen. The amount of buccal cortical bone thickness ranged between 1.89 mm, 10 mm anterior of the mental foramen, and 2.16 mm, 10 mm posterior to its location. At the A10 mm level, cortical thickness showed a marginal statistically significant difference between A5 and A10 mm. The total amount of bone thickness ranged from 10.19 to 12.06 mm. At the locations studied around the mental foramen, a mean bicortical bone thickness of 10-12 mm was measured. No large variation in the thickness was found between bicortical bone thicknesses in the measured locations around the mental foramen. Thorough evaluation on a case-by-case basis is advisable. © 2010 John Wiley & Sons A/S.

  6. The application of nanomaterials in controlled drug delivery for bone regeneration.

    Science.gov (United States)

    Shi, Shuo; Jiang, Wenbao; Zhao, Tianxiao; Aifantis, Katerina E; Wang, Hui; Lin, Lei; Fan, Yubo; Feng, Qingling; Cui, Fu-zhai; Li, Xiaoming

    2015-12-01

    Bone regeneration is a complicated process that involves a series of biological events, such as cellular recruitment, proliferation and differentiation, and so forth, which have been found to be significantly affected by controlled drug delivery. Recently, a lot of research studies have been launched on the application of nanomaterials in controlled drug delivery for bone regeneration. In this article, the latest research progress in this area regarding the use of bioceramics-based, polymer-based, metallic oxide-based and other types of nanomaterials in controlled drug delivery for bone regeneration are reviewed and discussed, which indicates that the controlling drug delivery with nanomaterials should be a very promising treatment in orthopedics. Furthermore, some new challenges about the future research on the application of nanomaterials in controlled drug delivery for bone regeneration are described in the conclusion and perspectives part. Copyright © 2015 Wiley Periodicals, Inc.

  7. Some arachnidan peptides with potential medical application

    Directory of Open Access Journals (Sweden)

    ME De Lima

    2010-01-01

    Full Text Available The search for new active drugs that can alleviate or cure different diseases is a constant challenge to researchers in the biological area and to the pharmaceutical industry. Historically, research has focused on the study of substances from plants. More recently, however, animal venoms have been attracting attention and studies have been successful in addressing treatment of accidents. Furthermore, venoms and their toxins have been considered good tools for prospecting for new active drugs or models for new therapeutic drugs. In this review, we discuss some possibilities of using different toxins, especially those from arachnid venoms, which have shown some potential application in diseases involving pain, hypertension, epilepsy and erectile dysfunction. A new generation of drugs is likely to emerge from peptides, including those found in animal venoms.

  8. Graphene plasmonics: physics and potential applications

    Directory of Open Access Journals (Sweden)

    Huang Shenyang

    2016-10-01

    Full Text Available Plasmon in graphene possesses many unique properties. It originates from the collective motion of massless Dirac fermions, and the carrier density dependence is distinctively different from conventional plasmons. In addition, graphene plasmon is highly tunable and shows strong energy confinement capability. Most intriguingly, as an atom-thin layer, graphene and its plasmon are very sensitive to the immediate environment. Graphene plasmons strongly couple to polar phonons of the substrate, molecular vibrations of the adsorbates, and lattice vibrations of other atomically thin layers. In this review, we present the most important advances in graphene plasmonics field. The topics include terahertz plasmons, mid-infrared plasmons, plasmon-phonon interactions, and potential applications. Graphene plasmonics opens an avenue for reconfigurable metamaterials and metasurfaces; it is an exciting and promising new subject in the nanophotonics and plasmonics research field.

  9. Microfluidic desalination techniques and their potential applications.

    Science.gov (United States)

    Roelofs, S H; van den Berg, A; Odijk, M

    2015-09-07

    In this review we discuss recent developments in the emerging research field of miniaturized desalination. Traditionally desalination is performed to convert salt water into potable water and research is focused on improving performance of large-scale desalination plants. Microfluidic desalination offers several new opportunities in comparison to macro-scale desalination, such as providing a platform to increase fundamental knowledge of ion transport on the nano- and microfluidic scale and new microfluidic sample preparation methods. This approach has also lead to the development of new desalination techniques, based on micro/nanofluidic ion-transport phenomena, which are potential candidates for up-scaling to (portable) drinking water devices. This review assesses microfluidic desalination techniques on their applications and is meant to contribute to further implementation of microfluidic desalination techniques in the lab-on-chip community.

  10. Twenty years bone banking in Macedonia application and legislation

    International Nuclear Information System (INIS)

    Karevski, L.; Videovski, G.; Nospal, T.

    1999-01-01

    After establishing the Department for Bone Transplantation and Bone Bank as a part of the University Clinic for Orthopaedic Surgery in Skopje in 1978, we started our activities in bone banking. In the beginning we stored the transplants at -20 degree C in a deep-freezer using standard storage procedures. Since 1986 we stored the transplants at-70 degree C in a special deep-freezer. 1012 transplants were preserved in the Bone Bank. 657 of them (65%) were used in different procedures, mainly in tumor surgery (407), revision total hip replacement (I 70), elongation of long bones (66), pseudoarthroses (I 5) etc. The most common transplants used in our bone bank are femoral heads taken from live donors during THR procedures, or small parts of cortical and cancellous bones taken during TKR and different types of osteotomies. 187 transplants were rejected due to infection after a defect in the storage system. We had good incorporation of the grafts in most of the patients, although we had delayed incorporation in 26 patients (4%), total resorption of the graft in 9 patients (1.4%), and infection in 4 patients (0.6%). Fracture of the graft occurred in 3 cases (0.5%). After the recognition and becoming a regular member of the United Nations as a former Yugoslav Republic in 1992, Republic of Macedonia started with the so-called 'transitional' period in all parts of life, especially in legislation. After bringing the systemic Health Law in 199 1, the Parliament brought 'The Law for taking, exchange, transportation and transplantation of parts of the human body by reason of curing' in June 1995. This Law defines the conditions under which it is possible to take, store, process, exchange, transport and transplant parts of the human body by reason of curing and the rights, obligations and conditions that have to be fulfilled by the Health Organizations and other organizations engaged in these activities. This Law accepts 'brain death' item, as biological death concept. The cell

  11. Complex Macromolecular Architectures for Potential Biological Applications

    Science.gov (United States)

    Jung, Hwayoon

    This thesis describes original research aimed at the development of highly efficient synthetic methods towards complex polymer architectures. An explanation of different polymer architectures, their synthesis and applications, in particular as biomaterials, is provided. Dendronized polymers and block copolymers are identified as two classes of polymer architectures that are important for a variety of applications but whose fabrications still pose a challenge. In the macromonomer route for the synthesis of dendronized polymers, the preferred route due to complete and uniform dendron functionalization, high degrees of polymerization are difficult to achieve due to steric crowding. This limitation was overcome by incorporating linkers between the polymerizable group (norbornene) and the poly(amide)-based dendrons. By increasing the length of the linker, the rate of polymerization increased. The synthesis of block copolymers using non-living polymerization methods often requires the copolymerization of monomers by different polymerization mechanisms. This methodology is hampered by non-quantitative conversions of the precursor polymer into the required macroinitiator. This limitation was overcome by using a bifunctional initiator. Poly(norbornene)-block -poly(lactic acid)s were synthesized using a ruthenium initiator for the ring-opening metathesis polymerization (ROMP) and a hydroxy group to initiate the ring-opening polymerization (ROP) of L-lactide. This method opens up new routes for the creation of functional block copolymers that are created by a combination of ROMP and ROP. Finally, potential strategies towards the synthesis of complex polymer architectures for biomaterials using the methodologies developed in this thesis are described. Firstly, the synthesis of orthogonally functionalizable dendronized polymers for targeted drug-delivery is proposed. Second, studies to establish the relationship between architectures and properties for biological applications

  12. Osteogenic potential of bone marrow stromal cells on smooth, roughened, and tricalcium phosphate-modified titanium alloy surfaces.

    LENUS (Irish Health Repository)

    Colombo, John S

    2012-09-01

    This study investigated the influence of smooth, roughened, and tricalcium phosphate (TCP)-coated roughened titanium-aluminum-vanadium (Ti-6Al-4V) surfaces on the osteogenic potential of rat bone marrow stromal cells (BMSCs).

  13. [Osteogenic potential of bone marrow mesenchymal stem cells from ovariectomied osteoporotic rat].

    Science.gov (United States)

    Li, Dong-ju; Ge, Dong-xia; Wu, Wen-chao; Wu, Jiang; Li, Liang

    2005-05-01

    To investigate the difference of osteogenic potential of bone marrow mesenchymal stem cells (MSCs) between healthy rats and osteoporotic rats. We established the animal model of osteoporosis by performing ovariectom on the 3-month-old female Sprague-Dawley rats. Bone marrow mesenchymal stem cells(MSCs) were isolated from the rats of control group and of ovariectomized (ovx) group by means of the density-gradient centrifugation method, and the 3rd-4th passage MSCs were used in all the experiments. The experiments comprised 4 groups: (1) Marrow mesenchymal stem cells control group (MSCs control group); (2) Marrow mesenchymal stem cells ovx group (MSCs ovx group); (3) Osteogenesis induction control group (OSI control group); (4) Osteogenesis induction ovx group (OSI ovx group). Cell cycle and proliferation index (PI) of MSCs were detected by flow cytometry. The expression of alkaline phosphatase (ALP) was detected by dynamics method with substrate of phosphoric acid para-Nitro benzene. The levels of osteocalcin were detected with the isotope labelling method. (1) PI of MSCs was lower in MSCs ovx group than in MSCs control group. (2) The expression of alkaline phosphatase (ALP) was much higher in OSI control group than in the MSCs control group; the expression of alkaline phosphatase (ALP) was much higher in the OSI control group than in OSI ovx group after 7-day and 14-day osteogenic induction. (3) The level of osteocalcin was much higher in the OSI control group than in the MSCs control group after 14-day, 21-day, 28-day osteogenic induction. The level of osteocalcin was much higher in the OSI control group than in the OSI ovx group. Both the proliferative potential and the osteogenic potential of bone marrow mesenchymal stem cells (MSCs) from the ovariectomized osteoporotic rat are decreased.

  14. Does intrawound application of vancomycin influence bone healing in spinal surgery?

    Science.gov (United States)

    Eder, Claudia; Schenk, Stefan; Trifinopoulos, Jana; Külekci, Büsra; Kienzl, Melanie; Schildböck, Sabrina; Ogon, Michael

    2016-04-01

    Surgical site infections represent a major complication of spinal surgery. The application of lyophilised vancomycin into the wound is reported to significantly decrease infection rates. As concentrations applied locally can exceed the minimal bacterial inhibitory concentration for more than a 1000-fold, toxic side effects on local tissue may be possible. Primary osteoblast cell cultures were generated from bone tissue samples of 10 patients. Samples were incubated in absence or presence of either 3, 6 or 12 mg/cm(2) vancomycin according to a planned phase I clinical trial protocol. Changes in pH, osteoblast migration, proliferation and viability were analysed. Alkaline phosphatase as well as mineralisation patterns was studied. The application of more than 3 mg/cm(2) vancomycin induced a decline of pH. The migration potential of osteoblasts was decreased from 100% (control samples) to zero (12 mg/cm(2) vancomycin) in a dose-dependant manner. Cell proliferation was significantly inhibited at dosages above 3 mg/cm(2). Significant cell death was observed if the dosage applied exceeded 6 mg/cm(2). The synthesis of alkaline phosphatase was markedly reduced in all dosages applied and calcium deposition was significantly decreased in dosages above 3 mg/cm(2). As bone remodelling requires the immigration, proliferation and differentiation of osteoblasts at the fusion site, high dosages of intrawound vancomycin might interfere with regenerative processes and increase the risk of non-union. To allow an appropriate balance of infection risk and the risk of non-union, the minimal local concentration required should be determined by controlled in vivo studies.

  15. Potential Osteoporosis Recovery by Deep Sea Water through Bone Regeneration in SAMP8 Mice

    Directory of Open Access Journals (Sweden)

    Hen-Yu Liu

    2013-01-01

    Full Text Available The aim of this study is to examine the therapeutic potential of deep sea water (DSW on osteoporosis. Previously, we have established the ovariectomized senescence-accelerated mice (OVX-SAMP8 and demonstrated strong recovery of osteoporosis by stem cell and platelet-rich plasma (PRP. Deep sea water at hardness (HD 1000 showed significant increase in proliferation of osteoblastic cell (MC3T3 by MTT assay. For in vivo animal study, bone mineral density (BMD was strongly enhanced followed by the significantly increased trabecular numbers through micro-CT examination after a 4-month deep sea water treatment, and biochemistry analysis showed that serum alkaline phosphatase (ALP activity was decreased. For stage-specific osteogenesis, bone marrow-derived stromal cells (BMSCs were harvested and examined. Deep sea water-treated BMSCs showed stronger osteogenic differentiation such as BMP2, RUNX2, OPN, and OCN, and enhanced colony forming abilities, compared to the control group. Interestingly, most untreated OVX-SAMP8 mice died around 10 months; however, approximately 57% of DSW-treated groups lived up to 16.6 months, a life expectancy similar to the previously reported life expectancy for SAMR1 24 months. The results demonstrated the regenerative potentials of deep sea water on osteogenesis, showing that deep sea water could potentially be applied in osteoporosis therapy as a complementary and alternative medicine (CAM.

  16. Luminescent Metal Nanoclusters for Potential Chemosensor Applications

    Directory of Open Access Journals (Sweden)

    Muthaiah Shellaiah

    2017-12-01

    Full Text Available Studies of metal nanocluster (M-NCs-based sensors for specific analyte detection have achieved significant progress in recent decades. Ultra-small-size (<2 nm M-NCs consist of several to a few hundred metal atoms and exhibit extraordinary physical and chemical properties. Similar to organic molecules, M-NCs display absorption and emission properties via electronic transitions between energy levels upon interaction with light. As such, researchers tend to apply M-NCs in diverse fields, such as in chemosensors, biological imaging, catalysis, and environmental and electronic devices. Chemo- and bio-sensory uses have been extensively explored with luminescent NCs of Au, Ag, Cu, and Pt as potential sensory materials. Luminescent bi-metallic NCs, such as Au-Ag, Au-Cu, Au-Pd, and Au-Pt have also been used as probes in chemosensory investigations. Both metallic and bi-metallic NCs have been utilized to detect various analytes, such as metal ions, anions, biomolecules, proteins, acidity or alkalinity of a solution (pH, and nucleic acids, at diverse detection ranges and limits. In this review, we have summarized the chemosensory applications of luminescent M-NCs and bi-metallic NCs.

  17. Potential applications of insect symbionts in biotechnology.

    Science.gov (United States)

    Berasategui, Aileen; Shukla, Shantanu; Salem, Hassan; Kaltenpoth, Martin

    2016-02-01

    Symbiotic interactions between insects and microorganisms are widespread in nature and are often the source of ecological innovations. In addition to supplementing their host with essential nutrients, microbial symbionts can produce enzymes that help degrade their food source as well as small molecules that defend against pathogens, parasites, and predators. As such, the study of insect ecology and symbiosis represents an important source of chemical compounds and enzymes with potential biotechnological value. In addition, the knowledge on insect symbiosis can provide novel avenues for the control of agricultural pest insects and vectors of human diseases, through targeted manipulation of the symbionts or the host-symbiont associations. Here, we discuss different insect-microbe interactions that can be exploited for insect pest and human disease control, as well as in human medicine and industrial processes. Our aim is to raise awareness that insect symbionts can be interesting sources of biotechnological applications and that knowledge on insect ecology can guide targeted efforts to discover microorganisms of applied value.

  18. POTENTIAL APPLICATIONS OF BIOCHAR FOR COMPOSTING

    Directory of Open Access Journals (Sweden)

    Krystyna Malińska

    2014-10-01

    for composting of materials with high moisture and/or nitrogen contents. The addition of biochar to composting mixtures can reduce ammonia emissions, and thus limit nitrogen losses during composting, increase water holding capacity and retention of nutrients. Biochar can also function as a carrier substrate for microbial inoculants and a scrubing material used in biofilters at composting facilities. Due to the fact that the literature does not provide many examples of biochar applications for composting, and there is little known about the effects of biochar added to composting mixtures on composting dynamics and properties of final composts, futher investigations should focus on mechanisms of biochar-composting mixtures interactions and analysis of properties of biochar-based composts. The overall goal of the article is to analyze the potentials of biochars for composting, to report the effects of various biochars on composting dynamics and quality of produced biochar-based composts, and to indicate the areas of further studies on biochar properties that would allow optimization of composting and improve the quality of final products.

  19. Bone regeneration potential of stem cells derived from periodontal ligament or gingival tissue sources encapsulated in RGD-modified alginate scaffold.

    Science.gov (United States)

    Moshaverinia, Alireza; Chen, Chider; Xu, Xingtian; Akiyama, Kentaro; Ansari, Sahar; Zadeh, Homayoun H; Shi, Songtao

    2014-02-01

    Mesenchymal stem cells (MSCs) provide an advantageous alternative therapeutic option for bone regeneration in comparison to current treatment modalities. However, delivering MSCs to the defect site while maintaining a high MSC survival rate is still a critical challenge in MSC-mediated bone regeneration. Here, we tested the bone regeneration capacity of periodontal ligament stem cells (PDLSCs) and gingival mesenchymal stem cells (GMSCs) encapsulated in a novel RGD- (arginine-glycine-aspartic acid tripeptide) coupled alginate microencapsulation system in vitro and in vivo. Five-millimeter-diameter critical-size calvarial defects were created in immunocompromised mice and PDLSCs and GMSCs encapsulated in RGD-modified alginate microspheres were transplanted into the defect sites. New bone formation was assessed using microcomputed tomography and histological analyses 8 weeks after transplantation. Results confirmed that our microencapsulation system significantly enhanced MSC viability and osteogenic differentiation in vitro compared with non-RGD-containing alginate hydrogel microspheres with larger diameters. Results confirmed that PDLSCs were able to repair the calvarial defects by promoting the formation of mineralized tissue, while GMSCs showed significantly lower osteogenic differentiation capability. Further, results revealed that RGD-coupled alginate scaffold facilitated the differentiation of oral MSCs toward an osteoblast lineage in vitro and in vivo, as assessed by expression of osteogenic markers Runx2, ALP, and osteocalcin. In conclusion, these results for the first time demonstrated that MSCs derived from orofacial tissue encapsulated in RGD-modified alginate scaffold show promise for craniofacial bone regeneration. This treatment modality has many potential dental and orthopedic applications.

  20. Auditory brainstem and cortical potentials following bone-anchored hearing aid stimulation.

    Science.gov (United States)

    Rahne, Torsten; Ehelebe, Thomas; Rasinski, Christine; Götze, Gerrit

    2010-11-30

    Patients suffering from conductive or mixed hearing loss and Single-Sided Deafness may benefit from implantable hearing devices relying on bone conducted auditory stimulation. However, with only passively cooperative patients, objective methods are needed to estimate the aided and unaided pure-tone audiogram. This study focuses on the feasibility aspect of an electrophysiological determination of the hearing thresholds with bone-anchored hearing aid stimulation. Therefore, 10 normal-hearing subjects were provided with a Baha Intenso (Cochlear Ltd.) which was temporarily connected to the Baha Softband (Cochlear Ltd.). Auditory evoked potentials were measured by auditory stimulation paradigm used in clinical routine. The amplitudes, latencies, and thresholds of the resulting auditory brainstem responses (ABR) and the cortically evoked responses (CAEP) were correlated with the respective responses without the use of the Baha Intenso. The recording of ABR and CAEP by delivering the stimuli to the Baha results in response waveforms which are comparable to those evoked by earphone stimulation and appears appropriate to be measured using the Baha Intenso as stimulator. At the ABR recordings a stimulus artifact at higher stimulation levels and a constant latency shift caused by the Baha Intenso has to be considered. The CAEP recording appeared promising as a frequency specific objective method to approve the fitting of bone-anchored hearing aids. At all measurements, the ABR and CAEP thresholds seem to be consistent with the normal hearing of the investigated participants. Thus, a recording of auditory evoked potentials using a Baha is in general possible if specific limitations are considered. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. Clinical Application of Human Mesenchymal Stromal Cells for Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Anindita Chatterjea

    2010-01-01

    Full Text Available The gold standard in the repair of bony defects is autologous bone grafting, even though it has drawbacks in terms of availability and morbidity at the harvesting site. Bone-tissue engineering, in which osteogenic cells and scaffolds are combined, is considered as a potential bone graft substitute strategy. Proof-of-principle for bone tissue engineering using mesenchymal stromal cells (MSCs has been demonstrated in various animal models. In addition, 7 human clinical studies have so far been conducted. Because the experimental design and evaluation parameters of the studies are rather heterogeneous, it is difficult to draw conclusive evidence on the performance of one approach over the other. However, it seems that bone apposition by the grafted MSCs in these studies is observed but not sufficient to bridge large bone defects. In this paper, we discuss the published human clinical studies performed so far for bone-tissue regeneration, using culture-expanded, nongenetically modified MSCs from various sources and extract from it points of consideration for future clinical studies.

  2. Polymer-ceramic nanocomposites for applications in the bone surgery

    International Nuclear Information System (INIS)

    Stodolak, E; Gadomska, K; Lacz, A; Bogun, M

    2009-01-01

    The subject of this work was preparation and investigation of properties of a nanocomposite material based on polymer matrix modified with nanometric silica particles (SiO 2 ). The composite matrix consisted of resorbable P(L/DL)LA polymer with certified biocompatibility. Nanometric silica was introduced into the matrix by means of ultrasonic homogenisation and/or mechanical stirring. The silica was introduced directly e.g. as nanoparticles or inside calcium alginate fibres which contained 3 wt.% of amorphous SiO 2 . Proper dispersion of nano-filliers was confirmed by means of thermal analysis (TG/DTA, DSC). It was observed, that the presence of inorganic nanoparticles influenced several surface parameters of the nanocomposites i.e. hydrophility (a decrease of surface energy) and topography (both in micro- and nano-scale). Additionally, the nanocomposites exhibited enhanced mechanical properties (Young's modulus, tensile strength) compared to the pure polymer. The nanocomposites were bioactive materials (SBF/3 days/37 deg. C). Biological tests (MTT test) showed a good viability of human osteoblasts (hFOB 1.19) in contact with the nanocomposites surface. Results of preliminary biological tests carried out with the use of mother cells extracted from human bone marrow showed that the nanocomposites may provide differenation of bone cells.

  3. [Clinical application of bone-anchored hearing aid implantation].

    Science.gov (United States)

    Xia, Yin; Zhang, Hua; Gong, Shu-sheng; Wang, Dan-ni; Zheng, Ya-li; Li, Yu-ling; Dong, Bo-ya; Han, De-min

    2013-08-01

    To discuss the indications, surgery methods and effects of the BAHA implantation by analyzing the patients' medical records of bone-anchored hearing aids(BAHA). Retrospective analyzed the records of 16 patients of BAHA implantation, including nine males and seven females. Their average age was 31 years old (8-53ys). Nine of them were congenital ear malformation, two were chronic suppurative otitis media, two were otosclerosis and three were unilateral severe sensorineural deafness. We evaluated their pure tone audiometry (PTA), speech audiometry and temporal CT before the surgery, and evaluated the aided PTA in soundfield and speech audiometry in sound field. These patients received BAHA implantation and installed the speech processor their months later. The average preoperative PTA measurements (PTA at 0.5, 1, 2, 4 kHz) was (63.2 ± 19.0) dB HL and postoperative aided PTA in sound field was (35.5 ± 10.9)dB HL. The average improvement in Hearing In Noise Test (HINT) was 37.0% ± 31.7%. The average improvement in Mandarin Speech Test was 76.0% ± 19.7%. After 4-16 months' follow-up, no significant complications were recorded. BAHA is a safe and effective bone implantable hearing device.

  4. Tooth apatite as a bone substitute: an experimental study and clinical applications

    International Nuclear Information System (INIS)

    Eun-Seok Kim; Pill-Hoon Choung

    1999-01-01

    The purpose of this study is to evaluate the usefulness of calcined teeth powder as biological apatite. The animal experiment was performed in 36 rabbits aging 6 weeks and weighing 1.6 kg. In experimental group, tooth apatite powder was implanted to 10 mm bony defects in diameter made on the cranial bone of the rabbits. As control groups, synthetic porous hydroxyapatite and resorbable type calcium carbonate were implanted to the defects of same size. Each group was sacrificed in 1, 2, 4, 6, 8, 12 weeks after the surgery. Specimens were prepared for decalcified samples and observed by a light microscope. And we also performed quantitative analysis of new bone formation through image analysis using computer. In clinical applications, we used tooth apatite alone or mixed with decalcified freeze-dried bone for reconstruction of bony defects in 15 patients undergone enucleation of cyst or ameloblastoma. The obtained results were as follows; 1) The powder of the calcined teeth was called as 'tooth apatite' and it seemed to have biocompatibility in rabbits and human. 2) In group of tooth apatite, after 4 weeks of operation, new bone directly bonded to the particles was observed. And in 12 weeks of it, new bone occupied most of the bony defects. In 6 weeks, resorption of the tooth apatite particles was observed. Thus the tooth apatite was regarded as one of resorbable apatite. 3) The group of tooth apatite showed new bone formation similar to the group of porous hydroxyapatite, but they were inferior to the group of resorbable calcium carbonate. 4) In clinical application, tooth apatite had biocompatibility and new bone formation was observed without any complication except for 1 case. So we think it is a useful bone substitute with osteoconductivity

  5. Bioactive polymeric–ceramic hybrid 3D scaffold for application in bone tissue regeneration

    International Nuclear Information System (INIS)

    Torres, A.L.; Gaspar, V.M.; Serra, I.R.; Diogo, G.S.; Fradique, R.; Silva, A.P.; Correia, I.J.

    2013-01-01

    The regeneration of large bone defects remains a challenging scenario from a therapeutic point of view. In fact, the currently available bone substitutes are often limited by poor tissue integration and severe host inflammatory responses, which eventually lead to surgical removal. In an attempt to address these issues, herein we evaluated the importance of alginate incorporation in the production of improved and tunable β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) three-dimensional (3D) porous scaffolds to be used as temporary templates for bone regeneration. Different bioceramic combinations were tested in order to investigate optimal scaffold architectures. Additionally, 3D β-TCP/HA vacuum-coated with alginate, presented improved compressive strength, fracture toughness and Young's modulus, to values similar to those of native bone. The hybrid 3D polymeric–bioceramic scaffolds also supported osteoblast adhesion, maturation and proliferation, as demonstrated by fluorescence microscopy. To the best of our knowledge this is the first time that a 3D scaffold produced with this combination of biomaterials is described. Altogether, our results emphasize that this hybrid scaffold presents promising characteristics for its future application in bone regeneration. - Graphical abstract: B-TCP:HA–alginate hybrid 3D porous scaffolds for application in bone regeneration. - Highlights: • The produced hybrid 3D scaffolds are prone to be applied in bone tissue engineering. • Alginate coated 3D scaffolds present high mechanical and biological properties. • In vitro assays for evaluation of human osteoblast cell attachment in the presence of the scaffolds • The hybrid 3D scaffolds present suitable mechanical and biological properties for use in bone regenerative medicine

  6. Bone Marrow Stem Cell Derived Paracrine Factors for Regenerative Medicine: Current Perspectives and Therapeutic Potential

    Directory of Open Access Journals (Sweden)

    Tom J. Burdon

    2011-01-01

    Full Text Available During the past several years, there has been intense research in the field of bone marrow-derived stem cell (BMSC therapy to facilitate its translation into clinical setting. Although a lot has been accomplished, plenty of challenges lie ahead. Furthermore, there is a growing body of evidence showing that administration of BMSC-derived conditioned media (BMSC-CM can recapitulate the beneficial effects observed after stem cell therapy. BMSCs produce a wide range of cytokines and chemokines that have, until now, shown extensive therapeutic potential. These paracrine mechanisms could be as diverse as stimulating receptor-mediated survival pathways, inducing stem cell homing and differentiation or regulating the anti-inflammatory effects in wounded areas. The current review reflects the rapid shift of interest from BMSC to BMSC-CM to alleviate many logistical and technical issues regarding cell therapy and evaluates its future potential as an effective regenerative therapy.

  7. [Research progress on application of carbon nanotubes in bone tissue engineering scaffold].

    Science.gov (United States)

    Yao, Mengzhu; Sheng, Xiaoxia; Lin, Jun; Gao, Jianqing

    2016-03-01

    Carbon nanotubes possess excellent mechanical and electrical properties and demonstrate broad application prospects in medical fields. Carbon nanotubes are composed of inorganic materials, natural biodegradable polymer or synthetic biodegradable polymer. The composite bone tissue engineering scaffolds are constructed by particle-hole method, lyophilization, microsphere aggregation method, electrostatic spinning or three-dimensional printing. Composite scaffolds overcome the shortcomings of single material and have good biocompatibility, osteoconduction and osteoinduction. With the study of surface chemistry, toxicology, and biocompatibility, a degradable "human-friendly" carbon nanotubes composite bone tissue scaffold will be available; and under the drive of new fabrication techniques, the clinical application of carbon nanotubes composite bone tissue engineering scaffolds will be better developed.

  8. Nanohybrid Electro-Coatings Toward Therapeutic Implants with Controlled Drug Delivery Potential for Bone Regeneration.

    Science.gov (United States)

    Patel, Kapil D; Singh, Rajendra K; Mahapatra, Chinmaya; Lee, Eun-Jung; Kim, Hae-Won

    2016-10-01

    Coatings of metallic implants facilitate a new bioactive interface that favors osteogenic responses and bone formation. Providing a therapeutic capacity to the coatings, involving with a sustainable and controllable delivery of drug molecules, significantly improves the bone regenerative potential. Here we design a novel nanocomposite coating, made of mesoporous silica-shelled hydroxyapatite (MS-HA) nanoparticles and chitosan (Chi), incorporating osteogenic drug dexamethasone phosphate (Dex(P)) within the MS-HA, by the process of an electrophoretic deposition (EPD). MS-HA, produced by a sol–gel reaction of silica onto an HA nanorod, exhibited mono-dispersed core–shell nanoparticles with a size of ∼40 nm and a shell thickness of ∼25 nm. The highly mesoporous structure enabled an effective loading of Dex(P) onto the nanocarriers, showing a loading capacity as high as 15% by weight. The Dex(P) loaded MS-HA were homogenized with Chi in acidic ethanol/water to allow for the EPD process. Nanocomposite coatings were produced well, forming thicknesses a few micrometers largely tunable with EPD parameters and exhibiting MS-HA nanoparticles evenly distributed within Chi matrix. While Dex(P) release from the bare MS-HA nanocarrier was very abrupt, showing a complete release within 24 h, the Dex(P) release from the nanocomposite coatings profiled a highly sustainable pattern over a month. Rat mesenchymal stem cells cultured on the Dex(P)-releasing coatings were substantially stimulated to an osteoblastic lineage, presenting enhanced alkaline phosphate activity and higher levels of osteogenic genes, with respect to coatings free of Dex(P). An indirect culture test also confirmed the long-term release effects of Dex(P) from the coatings over 4 weeks. The currently-developed nanocomposite EPD coatings, with a capacity to load osteogenic drug at large quantity and to deliver for a long-term period, are considered as a promising therapeutic coating platform for metallic

  9. Intrathecal application of autologous bone marrow cell preparations in parkinsonian syndromes

    DEFF Research Database (Denmark)

    Storch, Alexander; Csoti, Ilona; Eggert, Karla

    2012-01-01

    A growing number of patients is treated with intrathecal application of autologous bone marrow cells (aBMCs), but clinical data are completely lacking in movement disorders. We provide first clinical data on efficacy and safety of this highly experimental treatment approach in parkinsonian...

  10. Bone marrow mononuclear stem cells: potential in the treatment of myocardial infarction

    Directory of Open Access Journals (Sweden)

    Anne-Laure Leblond

    2009-12-01

    Full Text Available Anne-Laure Leblond, John O’Sullivan, Noel Caplice1Centre for Research in Vascular Biology (CRVB, Biosciences Institute, University College Cork, Cork, IrelandAbstract: Despite advances in the management of myocardial infarction, congestive heart failure following myocardial infarction continues to be a major worldwide medical problem. Mononuclear cells from bone marrow are currently being studied as potential candidates for cellbased therapy to repair and regenerate damaged myocardium, with mixed results. The success of this strategy requires structural repair through both cardiomyogenesis and angiogenesis but also functional repair. However, pre-clinical and clinical studies with the intracoronary administration of cells indicate limited cardiomyogenesis and cell survival, controversial functional benefit and suggest paracrine effects mediated by the administered cells. Further investigations for optimizing therapeutic benefit focus on the requirement for stable cell engraftment and the involvement of cytokines in this process. This includes a large and varied range of strategies including cell or heart pre-treatment, tissue engineering and protein therapy. Although cellbased therapy holds promise in the future treatment of myocardial infarction, its current use is significantly hampered by biological and technological challenges.Keywords: bone marrow mononuclear cells, myocardial infarction, cardiac cell therapy

  11. Preparation of collagen/hydroxyapatite/alendronate hybrid hydrogels as potential scaffolds for bone regeneration.

    Science.gov (United States)

    Ma, Xin; He, Zhiwei; Han, Fengxuan; Zhong, Zhiyuan; Chen, Liang; Li, Bin

    2016-07-01

    Development of biomimetic scaffolds represents a promising direction in bone tissue engineering. In this study, we designed a two-step process to prepare a type of biomimetic hybrid hydrogels that were composed of collagen, hydroxyapatite (HAP) and alendronate (ALN), an anti-osteoporosis drug. First, water-soluble ALN-conjugated HAP (HAP-ALN) containing 4.0wt.% of ALN was synthesized by treating HAP particles with ALN. Hydrogels were then formed from HAP-ALN conjugate and collagen under physiological conditions using genipin (GNP) as the crosslinker. Depending on the ALN/collagen molar ratio and GNP concentration, the gelation time of hydrogels ranged from 5 to 37min. Notably, these hybrid hydrogels exhibited markedly improved mechanical property (storage modulus G'=38-187kPa), higher gel contents, and lower swelling ratios compared to the hydrogels prepared from collagen alone under similar conditions. Moreover, they showed tunable degradation behaviors against collagenase. The collagen/HAP-ALN hybrid hydrogels supported the adhesion and growth of murine MC3T3-E1 osteoblastic cells well. Such tough yet enzymatically degradable hybrid hydrogels hold potential as scaffolds for bone tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. The effect of heparan sulfate application on bone formation during distraction osteogenesis.

    Science.gov (United States)

    Gdalevitch, Marie; Kasaai, Bahar; Alam, Norine; Dohin, Bruno; Lauzier, Dominique; Hamdy, Reggie C

    2013-01-01

    Bone morphogenetic proteins (BMPs) are recognized for their ability to induce bone formation in vivo and in vitro. Their osteogenic and osteoinductive properties are tightly regulated by the secretion of specific BMP antagonists, which have been shown to physically bind and sometimes be blocked by the extracellular proteoglycan heparan sulphate side chains (from hereon referred to as HS). The purpose of this study was to investigate if local application of 5 µg of HS proteoglycan to a bone regenerate site in a mouse model of distraction osteogenesis (DO) can accelerate bone healing and affect the expression of key members of the BMP signaling pathway. DO was performed on the right tibia of 115 adult male wild-type mice. At mid-distraction (day 11), half the group was injected locally with 5 µg of HS, while the other half was injected with saline. The mice were sacrificed at 2 time-points: mid-consolidation (34 days) and full consolidation (51 days). The distracted tibial zone was then collected for analysis by μCT, radiology, biomechanical testing, immunohistochemistry, and histology. While μCT data showed no statistically significant difference in bone formation, the results of biomechanical testing in stiffness and ultimate force were significantly lower in the HS-injected bones at 51 days, compared to controls. Immunohistochemistry results also suggested a decrease in expression of several key members of the BMP signaling pathway at 34 days. Furthermore, wound dehiscence and infection rates were significantly elevated in the HS group compared to the controls, which resulted in a higher rate of euthanasia in the treatment group. Our findings demonstrate that exogenous application of 5 µg of HS in the distracted gap of a murine model had a negative impact on bone and wound healing.

  13. The effect of heparan sulfate application on bone formation during distraction osteogenesis.

    Directory of Open Access Journals (Sweden)

    Marie Gdalevitch

    Full Text Available Bone morphogenetic proteins (BMPs are recognized for their ability to induce bone formation in vivo and in vitro. Their osteogenic and osteoinductive properties are tightly regulated by the secretion of specific BMP antagonists, which have been shown to physically bind and sometimes be blocked by the extracellular proteoglycan heparan sulphate side chains (from hereon referred to as HS. The purpose of this study was to investigate if local application of 5 µg of HS proteoglycan to a bone regenerate site in a mouse model of distraction osteogenesis (DO can accelerate bone healing and affect the expression of key members of the BMP signaling pathway. DO was performed on the right tibia of 115 adult male wild-type mice. At mid-distraction (day 11, half the group was injected locally with 5 µg of HS, while the other half was injected with saline. The mice were sacrificed at 2 time-points: mid-consolidation (34 days and full consolidation (51 days. The distracted tibial zone was then collected for analysis by μCT, radiology, biomechanical testing, immunohistochemistry, and histology. While μCT data showed no statistically significant difference in bone formation, the results of biomechanical testing in stiffness and ultimate force were significantly lower in the HS-injected bones at 51 days, compared to controls. Immunohistochemistry results also suggested a decrease in expression of several key members of the BMP signaling pathway at 34 days. Furthermore, wound dehiscence and infection rates were significantly elevated in the HS group compared to the controls, which resulted in a higher rate of euthanasia in the treatment group. Our findings demonstrate that exogenous application of 5 µg of HS in the distracted gap of a murine model had a negative impact on bone and wound healing.

  14. [The application of guided bone regeneration technique in the restoration of maxillary lateral incisor with bone defect].

    Science.gov (United States)

    Li, Zhuo-rui; Liu, Zhong-hao; Xu, Sheng; Xiao, Hui-juan; Zhou, Wen-juan

    2012-04-01

    To evaluate the clinical effectiveness and the satisfaction on aesthetic effectiveness of application of guided bone regeneration (GBR) technique in maxillary lateral incisor implant site. Ninety patients were selected who only lost maxillary lateral incisor and placed with 101 implants(the implant systems were 3i, Osstem, ITI, Ankylos, BLB). The final restorations were porcelain-fused-to-metal crowns. Clinical and X-ray examinations were conducted and esthetic results were observed at 3, 6,12 months after dental implant prosthetics. The follow-up time was 12 months, all patients achieved successful implantation and good osseointegration around the implant. The esthetic results were perfect .Among the 90 cases, 90.7%, 92.8% and 95.5% of the patients were satisfied with the final outcomes 3,6,12 months after prosthetics. Good clinical effectiveness and satisfaction on aesthetic effectiveness can be obtained with GBR technique applied in maxillary lateral incisor implant site. Appropriate use of GBR technique is the solution of bone defect of maxillary lateral incisor implant site.

  15. In vitro osteogenic potential of bone debris resulting from placement of titanium screw-type implants.

    NARCIS (Netherlands)

    Dhore, C.R.; Snel, S.J.; Jacques, S.V.; Naert, I.E.; Walboomers, X.F.; Jansen, J.A.

    2008-01-01

    OBJECTIVES: Histological sections of preclinical animal studies have shown that new bone formation around dental implants frequently contains debris derived from the original bone. Whether such debris by itself is osteogenic, i.e., can influence the process of new bone formation after implant

  16. EVALUATION OF BIOPHYSICAL PROPERTIES OF THE BONE TISSUE FOR BIOMEDICAL APPLICATIONS

    Directory of Open Access Journals (Sweden)

    I. V. Matveychuk

    2016-01-01

    Full Text Available Background and aim: The volume of reconstructive surgery in traumatology in recent decades has increased significantly due to an increase in traumas, numbers of affected in local military conflicts, and environmental deterioration. This has led to an increase in demand for plastic materials, and the need to create modern high technologies to meet this need, including alternative sources of bone implants. Any solution to this problem would involve an in-depth study of bone biophysical properties with innovative techniques to develop requirements to elaboration of new effective implants based on natural bone, as well as on natural or synthetic analogues. This study aimed exactly at these aspects. Materials and methods: We studied human bone samples taken from various parts of the skeleton aged from 3 to 89 years and animal (bovine bone samples aged from 1.5 to 2 years. Biophysical characteristics of the studied materials were assessed at the stage of sample preparation with original author's methods of physical and mechanical processing, in the process of analysis of patterns of normal changes in the bone structure and function, as well as during changes in its composition with age, anisotropy of the material and the level of structural organization. Structure patterns were studied by classical (light, scanning electron microscopy and advanced (acoustic microscopy techniques. Methods of engineering biomechanics were used to assess functional changes in macro and micro volumes of bone samples. Results: The main study results involve the development of innovative methods of sample preparation and structural and functional analysis. First of all, these are the methods of mechanical processing of bone fragments based on the use of hollow cylindrical milling cutters in the environment of limited amounts of mineralized biological tissues, as well as on the application of hydrodynamic cutting ensuring a delicate and highly efficient bone cut. Another

  17. Biphasic Calcium Phosphate Ceramics for Bone Regeneration and Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Sonja Ellen Lobo

    2010-01-01

    Full Text Available Biphasic calcium phosphates (BCP have been sought after as biomaterials for the reconstruction of bone defects in maxillofacial, dental and orthopaedic applications. They have demonstrated proven biocompatibility, osteoconductivity, safety and predictability in in vitro, in vivo and clinical models. More recently, in vitro and in vivo studies have shown that BCP can be osteoinductive. In the field of tissue engineering, they represent promising scaffolds capable of carrying and modulating the behavior of stem cells. This review article will highlight the latest advancements in the use of BCP and the characteristics that create a unique microenvironment that favors bone regeneration.

  18. Reticulocyte maturity index by flow cytometry: its applicability in radioinduced bone marrow aplasia

    International Nuclear Information System (INIS)

    Dubner, D.; Gisone, P.; Perez, M.R.

    1995-01-01

    Flow cytometric reticulocyte quantification was assayed in ten patients undergoing bone marrow transplantation (BMT) with previous conditioning chemotherapy and total body irradiation (TBI). A reticulocyte maturity index (RMI) was determined taking into account the RNA content. With de aim of testing the utility of RMI as an early predictor of functional recovery in marrow aplasia, other haematological indicators as neutrophils count were comparatively evaluated. Mean time elapsed between BMT and engraftment evidence by RMI was 17,6 days. In six patients the RMI was the earliest indicator of functional recovery. The applicability of this assay in the following of radioinduced bone marrow aplasia is discussed. (author). 4 refs., 4 figs., 2 tabs

  19. Survey of potential applications of superconducting suspensions

    International Nuclear Information System (INIS)

    Rao, D.K.; Bupara, S.S.

    1993-01-01

    The purpose of this report is to survey the recent developments in applying the bulk superconductors to mechanical applications. These applications, called superconducting suspensions, can be broadly divided into three groups - Passive Magnetic Bearings, Passive Superconducting Dampers and Active Superconducting Bearings. Basically, passive magnetic bearings utilize bulk superconductors to support a rotating shaft without contact while active superconducting bearings employ superconducting wires. Passive superconducting dampers, on the other hand, dissipate energy from a vibrating component. Over the past one year, dramatic improvements have been made in processing large-size specimens made of high grade bulk superconductors. As a result, they can meet the size requirements and load capacity requirements of many applications. With this size-scale up, one can utilize them in a wider number of applications than what was possible a few years back. At present several organizations have demonstrated the capability of passive magnetic bearings. The targeted applications include miniature cryoturboexpanders, cryoturbopumps, energy storage wheels and turbomolecular pumps. These demonstrations indicate that the passive magnetic bearings are closer to technology maturity. (orig.)

  20. The SBR and its biofilm application potentials.

    Science.gov (United States)

    Wilderer, P A; McSwain, B S

    2004-01-01

    Twenty plus years of experience, innovation, and research in the field of biological wastewater treatment and biofilm applications lead to the conclusion that biofilms are in many cases more desirable in reactors than suspended activated sludge. Biofilm reactors can provide very long biomass residence times even when the hydraulic influent loading is low. This makes them particularly suitable when treatment requires slow growing organisms with poor biomass yield or when the wastewater concentration is too low to support growth of activated sludge flocs. Regardless of the settling characteristics of biological aggregates or the hydraulic influent loading the metabolic activity in the reactor can be maintained at a high level. This paper reviews the application of biofilms in sequencing batch reactor (SBR) systems to treat non-readily biodegradable substrates, volatile organic waste constituents, complex waste streams requiring co-metabolism, and particulate wastewaters. Recent research using the SBR to form aerobic granular sludge as a special application of biofilms is also discussed.

  1. Profile, antioxidant potential, and applicability of phenolic ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-10-14

    ) of Spirulina platensis and assesses their antioxidant potential, applying them as a natural conservative in minimally processed apples. The phenolic extract showed 396 µg g-1 gallic acid, 347 µg g-1 of caffeic acid, 54 µg g-1.

  2. Potentials of RFID Application in Retailing

    DEFF Research Database (Denmark)

    Foscht, Thomas; Kotzab, Herbert; Maloles III, Cesar

    2008-01-01

    The willingness of retailers to adopt RFID systems, as well as finding optimal RFID applications has yet not been investigated. This paper examines the issues associated with the RFID adoption based on the results of a conjoint analysis. The conjoint measurement looked at the trade-off decisions...... among different possible set-ups of RFID applications in retailing companies. Considerable willingness to adopt, but low diffusion and a structure of preferences with respect to RFID features was shown throughout the examined retailing companies. Furthermore, differences were shown among different types...... of retailers in their preferences for RFID system features and clusters were implied....

  3. Microstructure and thermal diffusivity in hydroxyapatite, dense bone and metals for biomedical applications

    International Nuclear Information System (INIS)

    Mendez, M.; Diaz G, J.A.I.; Calderon, A.

    2007-01-01

    Full text: We report X-Ray diffraction and SEM analysis in hydroxyapatite obtained in powder form, as well as a SEM analysis in titanium, 316l stainless steel and dense bone in longitudinal and transversal cutting. Moreover, we realized a thermal diffusivity measurement in these materials in order to obtain the thermal compatibility between them. We use the photoacoustic technique in heat transmission configuration in order to obtain the thermal diffusivity values in the samples. Our results show a good thermal compatibility (74%) between hydroxyapatite and bone. Finally, it was obtained a one order of magnitude difference between the thermal diffusivity values of metallic samples and those corresponding values to bone and HA being this difference greater in titanium than in stainless steel, which is important to consider in some biomedical and dental applications. (Author)

  4. Nanopharmaceutics: the potential application of nanomaterials

    National Research Council Canada - National Science Library

    Liang, Xing-Jie

    2013-01-01

    ... delivery using nanobiotechnology as well as monitor biocompatibility and toxicity of nanomaterials for clinical use. This book focuses on significant aspects of nanomaterials for pharmaceutical applications based on the new development for cancer treatment, imaging diagnosis, formulation of new drug and biomolecules for therapeutic applica...

  5. Tensile behaviors of three-dimensionally free-formable titanium mesh plates for bone graft applications

    Science.gov (United States)

    He, Jianmei

    2017-11-01

    Present metal artificial bones for bone grafts have the problems like too heavy and excessive elastic modulus compared with natural bones. In this study, three-dimensionally (3D) free-formable titanium mesh plates for bone graft applications was introduced to improve these problems. Fundamental mesh shapes and patterns were designed under different base shapes and design parameters through three dimensional CAD tools from higher flexibility and strength points of view. Based on the designed mesh shape and patterns, sample specimens of titanium mesh plates with different base shapes and design variables were manufactured through laser processing. Tensile properties of the sample titanium mesh plates like volume density, tensile elastic modulus were experimentally and analytically evaluated. Experimental results showed that such titanium mesh plates had much higher flexibility and their mechanical properties could be controlled to close to the natural bones. More details on the mechanical properties of titanium mesh plates including compression, bending, torsion and durability will be carried out in future study.

  6. Automated cortical bone segmentation for multirow-detector CT imaging with validation and application to human studies.

    Science.gov (United States)

    Li, Cheng; Jin, Dakai; Chen, Cheng; Letuchy, Elena M; Janz, Kathleen F; Burns, Trudy L; Torner, James C; Levy, Steven M; Saha, Punam K

    2015-08-01

    Cortical bone supports and protects human skeletal functions and plays an important role in determining bone strength and fracture risk. Cortical bone segmentation at a peripheral site using multirow-detector CT (MD-CT) imaging is useful for in vivo assessment of bone strength and fracture risk. Major challenges for the task emerge from limited spatial resolution, low signal-to-noise ratio, presence of cortical pores, and structural complexity over the transition between trabecular and cortical bones. An automated algorithm for cortical bone segmentation at the distal tibia from in vivo MD-CT imaging is presented and its performance and application are examined. The algorithm is completed in two major steps-(1) bone filling, alignment, and region-of-interest computation and (2) segmentation of cortical bone. After the first step, the following sequence of tasks is performed to accomplish cortical bone segmentation-(1) detection of marrow space and possible pores, (2) computation of cortical bone thickness, detection of recession points, and confirmation and filling of true pores, and (3) detection of endosteal boundary and delineation of cortical bone. Effective generalizations of several digital topologic and geometric techniques are introduced and a fully automated algorithm is presented for cortical bone segmentation. An accuracy of 95.1% in terms of volume of agreement with manual outlining of cortical bone was observed in human MD-CT scans, while an accuracy of 88.5% was achieved when compared with manual outlining on postregistered high resolution micro-CT imaging. An intraclass correlation coefficient of 0.98 was obtained in cadaveric repeat scans. A pilot study was conducted to describe gender differences in cortical bone properties. This study involved 51 female and 46 male participants (age: 19-20 yr) from the Iowa Bone Development Study. Results from this pilot study suggest that, on average after adjustment for height and weight differences, males have

  7. Potential application of electron accelerators in Malaysia

    International Nuclear Information System (INIS)

    Nahrul Khair Alang Md Rashid; Khairul Zaman Mohd Dahlan

    1994-01-01

    Briefly discussed some applications of electron accelerators i.e. sterilization, pasteurization (high energy EBM - up to 10 MV), crosslinking of wire and cable and insulation (medium energy EBM - 1 to 5 MV), treatment of flue gases for removal of NO sub x and SO sub x from burning coal(low energy EBM - 700 to 900 kV), curing of surface coatings, printing ink, adhesives (low energy EBM - 200 to 500 kV); advantages and electron beam processing

  8. Long-term potentiation in bone – a role for glutamate in strain-induced cellular memory?

    Directory of Open Access Journals (Sweden)

    Genever Paul G

    2003-07-01

    Full Text Available Abstract Background The adaptive response of bone cells to mechanical strain is a primary determinant of skeletal architecture and bone mass. In vivo mechanical loading induces new bone formation and increases bone mineral density whereas disuse, immobilisation and weightlessness induce bone loss. The potency of mechanical strain is such that a single brief period of loading at physiological strain magnitude is able to induce a long-lasting osteogenic response that lasts for days. Although the process of mechanotransduction in bone is incompletely understood, observations that responses to mechanical strain outlast the duration of stimulation necessitate the existence of a form of cellular memory through which transient strain episodes are recorded, interpreted and remembered by bone cells. Recent evidence supports the existence of a complex multicellular glutamate-signalling network in bone that shares functional similarities to glutamatergic neurotransmission in the central nervous system. In neurones, these signalling molecules coordinate synaptic communication required to support learning and memory formation, through a complex process of long-term potentiation. Presentation of the hypothesis We hypothesise that osteoblasts use a cellular mechanism similar or identical to neuronal long-term potentiation in the central nervous system to mediate long-lasting changes in osteogenesis following brief periods of mechanical strain. Testing the hypothesis N-methyl-D-aspartate (NMDA receptor antagonism should inhibit the saturating response of mechanical strain and reduce the enhanced osteogenicity of segregated loading to that of an equivalent period of uninterrupted loading. Changes in α-amino-3-hydroxy-5-methyl-isoxazole propionate (AMPA receptor expression, localisation and electrophysiological responses should be induced by mechanical strain and inhibited by modulators of neuronal long-term potentiation. Implications of the hypothesis If true

  9. Profile, antioxidant potential, and applicability of phenolic ...

    African Journals Online (AJOL)

    ) of Spirulina platensis and assesses their antioxidant potential, applying them as a natural conservative in minimally processed apples. The phenolic extract showed 396 &µg g-1 gallic acid, 347 µg g-1 of caffeic acid, 54 µg g-1 salicylic acid ...

  10. Saccular function in otosclerosis patients: bone conducted-vestibular evoked myogenic potential analysis.

    Directory of Open Access Journals (Sweden)

    Amin Amali

    2014-02-01

    Full Text Available Vestibular involvements have long been observed in otosclerotic patients. Among vestibular structures saccule has the closest anatomical proximity to the sclerotic foci, so it is the most prone vestibular structure to be affected during the otosclerosis process. The aim of this study was to investigate the saccular function in patients suffering from otosclerosis, by means of Vestibular Evoked Myogenic Potential (VEMP. The material consisted of 30 otosclerosis patients and 20 control subjects. All participants underwent audiometric and VEMP testing. Analysis of tests results revealed that the mean values of Air-Conducted Pure Tone Average (AC-PTA and Bone-Conducted Pure Tone Average (BC-PTA in patients were 45.28 ± 15.57 and 19.68 ± 10.91, respectively and calculated 4 frequencies Air Bone Gap (ABG was 25.64 ± 9.95. The VEMP response was absent in 14 (28.57% otosclerotic ears. A statistically significant increase in latency of the p13 was found in the affected ears (P=0.004, differences in n23 latency did not reach a statistically significant level (P=0.112. Disparities in amplitude of p13-n23 in between two study groups was statistically meaningful (P=0.009, indicating that the patients with otosclerosis had lower amplitudes. This study tends to suggest that due to the direct biotoxic effect of the materials released from the otosclerosis foci on saccular receptors, there might be a possibility of vestibular dysfunction in otosclerotic patients.

  11. Evaluation of cell sheet application on one wall bone defect in Macaca nemestrina through periostin expression

    Science.gov (United States)

    Tamin, R. Y.; Soeroso, Y.; Amir, L.; Idrus, E.

    2017-08-01

    Chronic periodontitis is an oral disease in which the destruction of periodontal tissue leads to tooth loss. Regenerative therapy for attachment cannot be applied to one wall bone defects owing to the minimal existing healthy bone. Tissue engineering in the form of cell sheets has been developed to overcome this limitation. In a previous study, cell sheet application to a one wall bone defect in Macaca nemestrina showed good clinical results. To evaluate the effectiveness of cell sheet application histologically, the level of periostin expression in the gingival crevicular fluid (GCF) of M. nemestrina was determined. Periostin is a 90-kDa protein that regulates coordination and interaction for regeneration and tissue repair. A laboratory observation study was performed to see the differences in periostin levels in samples collected from M. nemestrina’s GCF, where a cell sheet was applied to the bone defect. Gel electrophoresis with SDS-PAGE was performed to detect periostin expression based on its molecular weight and to compare the expression band between the cell sheet and the control at 1, 2, and 3 weeks after treatment. The gel electrophoresis result shows different thicknesses of the protein band around the molecular weight of periostin between the cell sheet groups.

  12. [Advantages and Application Prospects of Deep Learning in Image Recognition and Bone Age Assessment].

    Science.gov (United States)

    Hu, T H; Wan, L; Liu, T A; Wang, M W; Chen, T; Wang, Y H

    2017-12-01

    Deep learning and neural network models have been new research directions and hot issues in the fields of machine learning and artificial intelligence in recent years. Deep learning has made a breakthrough in the applications of image and speech recognitions, and also has been extensively used in the fields of face recognition and information retrieval because of its special superiority. Bone X-ray images express different variations in black-white-gray gradations, which have image features of black and white contrasts and level differences. Based on these advantages of deep learning in image recognition, we combine it with the research of bone age assessment to provide basic datum for constructing a forensic automatic system of bone age assessment. This paper reviews the basic concept and network architectures of deep learning, and describes its recent research progress on image recognition in different research fields at home and abroad, and explores its advantages and application prospects in bone age assessment. Copyright© by the Editorial Department of Journal of Forensic Medicine.

  13. Adding MgO nanoparticles to hydroxyapatite-PLLA nanocomposites for improved bone tissue engineering applications.

    Science.gov (United States)

    Hickey, Daniel J; Ercan, Batur; Sun, Linlin; Webster, Thomas J

    2015-03-01

    Magnesium plays an important role in the body, mediating cell-extracellular matrix interactions and bone apatite structure and density. This study investigated, for the first time, the effects of adding magnesium oxide (MgO) nanoparticles to poly (l-lactic acid) (PLLA) and to hydroxyapatite (HA) nanoparticle-PLLA composites for orthopedic tissue engineering applications. Results showed that MgO nanoparticles significantly enhanced osteoblast adhesion and proliferation on HA-PLLA nanocomposites while maintaining mechanical properties (Young's modulus ∼1,000 MPa) suitable for cancellous bone applications. Additionally, osteoblasts (or bone-forming cells) cultured in the supernatant of degrading nanocomposites showed improved proliferation in the presence of magnesium, indicating that the increased alkalinity of solutions containing MgO nanocomposites had no toxic effects towards cells. These results together indicated the promise of further studying MgO nanoparticles as additive materials to polymers to enhance the integration of implanted biomaterials with bone. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Osteoinductive potential of demineralized rat bone increases with increasing donor age from birth to adulthood

    DEFF Research Database (Denmark)

    Pinholt, E M; Solheim, E

    1998-01-01

    Demineralized allogenic bone implanted in the subcutis or muscle of rodents causes formation of heterotopic bone by osteoinduction. The osteoinductive response may be weaker in primates than in rodents. It was suggested that the osteoinductive response of demineralized bone for clinical use could...... be enhanced by using young donors, because studies have indicated that the osteoinductive response is reduced in demineralized bone of old versus young donors. However, these findings may not represent a gradual decline in the osteoinductive property of bone matrix throughout the life span. We evaluated...... quantitatively, by uptake of strontium 85, the osteoinductive effect of demineralized bone matrix from newborn, 8-week-old (adolescent), and 8-month-old (adult) male Wistar rats implanted in the abdominal muscles of 8-week-old male Wistar rats. The osteoinductive response increased significantly with increasing...

  15. [Application of bone flap pedicled on retrograde branch of radial artery for treatment of old scaphoid bone fractures of type AO-B].

    Science.gov (United States)

    Sun, Qing-peng

    2015-05-01

    To investigate application of the bone flap pedicled on the retrograde branch of radial artery for treatment of old scaphoid bone fractures of type AO-B. From October 2007 to October 2011,41 patients with old scaphoid bone fractures of type AO-B were treated by transplantation of the bone flap pedicled on the retrograde branch of radial artery including 26 males and 15 females with an average of (27.3±4.5) years old ranging from 16 to 43 years old. The courses before operation ranged from 6 to 22 months with an average of 11 months. All fractures belonged to the type B of AO classification, that is old wrist fracture of scaphoid bone. All patients' wrist function (pain, function, motion, grip strength) were evaluated by Cooney's modifiedwrist scoring system before and 6 months after operation,and the conditions of bone healing were observed during the follow-up time. Among them, 36 patients were followed up from 4 to 15 months with an average of 8.3 months. The wounds were healed well without other complications as infection appearing. X-rays or CT confirmed that all fractures were healed completely. The Cooney wrist score was improved from preoperative 53.61±13.97 to postoperative 81.81±8.71 (Pfractures,which is scientific and has curative effects, and valuable for clinical application.

  16. Zeta potential in colloid science principles and applications

    CERN Document Server

    Hunter, Robert J; Rowell, R L

    2013-01-01

    Zeta Potential in Colloid Science: Principles and Applications covers the concept of the zeta potential in colloid chemical theory. The book discusses the charge and potential distribution at interfaces; the calculation of the zeta potential; and the experimental techniques used in the measurement of electrokinetic parameters. The text also describes the electroviscous and viscoelectric effects; applications of the zeta potential to areas of colloid science; and the influence of simple inorganic ions or more complex adsorbates on zeta potential. Physical chemists and people involved in the stu

  17. Potential applications of insect symbionts in biotechnology

    OpenAIRE

    Berasategui, A.; Shukla, S.; Salem, H.; Kaltenpoth, M.

    2016-01-01

    Symbiotic interactions between insects and microorganisms are widespread in nature and are often the source of ecological innovations. In addition to supplementing their host with essential nutrients, microbial symbionts can produce enzymes that help degrade their food source as well as small molecules that defend against pathogens, parasites, and predators. As such, the study of insect ecology and symbiosis represents an important source of chemical compounds and enzymes with potential biote...

  18. Vestibular evoked myogenic potentials (VEMPs) evoked by air- and bone-conducted stimuli in vestibular neuritis.

    Science.gov (United States)

    Govender, Sendhil; Dennis, Danielle L; Colebatch, James G

    2015-10-01

    To compare and characterise abnormalities for short latency vestibular evoked myogenic potentials (VEMPs) elicited by air- (AC) and two differing types of bone-conducted (BC) stimuli during vestibular neuritis (VN). AC (500Hz short tone bursts) and two BC stimuli (500Hz at the forehead and impulses at the mastoids) were used to evoke cervical and ocular potentials (cVEMPs and oVEMPs) in VN patients (n=22) and healthy subjects. More abnormalities were observed for the oVEMP than the cVEMP when using either AC 500Hz or BC 500Hz. The AC stimulus showed slightly more abnormalities than the BC 500Hz stimulus. In contrast, BC impulses produced frequent abnormalities for both oVEMPs and cVEMPs. The findings were modelled, based upon presumed selective lesions of the superior nerve. AC 500Hz stimulation was slightly better than BC 500Hz in demonstrating abnormalities in patients with VN. BC impulses behave as expected for a predominantly utricular stimulus. The relative contributions of saccular and utricular fibres differ for stimulus type and target reflex. AC 500Hz is as effective as BC 500Hz for investigating VN. BC impulses act most strongly on utricular afferents. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Current potential of radionuclide applications in therapy

    International Nuclear Information System (INIS)

    Navratil, L.

    1987-01-01

    A review is presented of the proceedings of the 4th Boettstein Collegium held in June, 1986 in Wuerenlingen (CH), debating new possibilities in applying radionuclides in the therapy of malignant diseases. The new possibilities are open with the development of new biological carriers with high detection capacities, especially monoclonal antibodies. Therapeutical applications are characterized of some radionuclides, mainly 131 I and 123 I, and beta and alpha radionuclides are listed promising for therapeutical uses. Therapeutical prospects are also outlined for immunotherapy. (L.O.). 1 ref

  20. Thermoluminescence: Potential Applications in Forensic Science

    Science.gov (United States)

    Ingham, J. D.; Lawson, D. D.

    1973-01-01

    In crime laboratories one of the most difficult operations is to determine unequivocally whether or not two samples of evidence of the same type were originally part of the same thing or were from the same source. It has been found that high temperature thermoluminescence (room temperature to 723 K) can be used for comparisons of this type, although work to date indicates that there is generally a finite probability for coincidental matching of glass or soil samples. Further work is required to determine and attempt to minimize these probabilities for different types of materials, and to define more clearly the scope of applicability of thermoluminescence to actual forensic situations.

  1. Nanotechnologies, technologies converging and potential biomedical applications

    International Nuclear Information System (INIS)

    Capuano, Vincenzo

    2005-01-01

    The applications of nanotechnology to biology and medicine appear really promising far diagnostics, for various therapeutic approaches and in medical instrumentations. The growing synergism among nanotechnology, biotechnology, information technology and cognitive sciences, their convergence (NBIC) from the nano scale, could involve on next decades great changes in medicine, from a reactive to a predictive and preventive approach. It is expected that NBIC converging technologies could achieve tremendous improvements in human abilities and enhance societal achievements. It appears therefore necessary a careful assessment of related social and ethical implications, in the framework of a constant dialogue between science and society [it

  2. Survey of potential electronic applications of high temperature superconductors

    International Nuclear Information System (INIS)

    Hammond, R.B.; Bourne, L.C.

    1991-01-01

    In this paper the authors present a survey of the potential electronic applications of high temperature superconductor (HTSC) thin films. During the past four years there has been substantial speculation on this topic. The authors will cover only a small fraction of the potential electronic applications that have been identified. Their treatment is influenced by the developments over the past few years in materials and device development and in market analysis. They present their view of the most promising potential applications. Superconductors have two important properties that make them attractive for electronic applications. These are (a) low surface resistance at high frequencies, and (b) the Josephson effect

  3. {sup 188}Re-labeled bisphosphonates as potential bifunctional agents for therapy in patients with bone metastases

    Energy Technology Data Exchange (ETDEWEB)

    El-Mabhouh, Amal [Faculty of Pharmacy and Pharmaceutical Sciences, 3118 Dentistry Pharmacy Center, University of Alberta, Edmonton Alta, T6G-2N8 (Canada); Mercer, John R. [Faculty of Pharmacy and Pharmaceutical Sciences, 3118 Dentistry Pharmacy Center, University of Alberta, Edmonton Alta, T6G-2N8 (Canada); Faculty of Medicine, 3118 Dentistry Pharmacy Center, University of Alberta, Edmonton Alta, T6G-2N8 (Canada)]. E-mail: john.mercer@ualberta.ca

    2005-04-01

    Two new bisphosphonates have been examined for their ability to bind {sup 188}Re and deliver it selectively to bone. The bisphosphonates are prototype compounds with potential to deliver rhenium radionuclides and a second therapy modality to bone metastases. A conjugate between diethylenetriaminepentaacetic acid and bisphosphonate (DTPA/BP) and a conjugate between 5-fluorouracil and bisphosphonate (5-FU/BP) were prepared and labeled at high radiochemical purity with {sup 188}Re and biodistribution studies were carried out in normal Balb/C mice. The compounds showed rapid blood clearance and elimination from soft tissues with substantial retention of activity in the bone comparable to {sup 188}Re-hydroxyethylidine diphosphonate used as a control. At 8 h bone activity was 3.51% of injected dose for {sup 188}Re-DTPA/BP and 6.38% of injected dose for {sup 188}Re-5-FU/BP representing 69.6% and 80.6% of total body radioactivity, respectively. The two compounds show the potential for combination therapy of painful bone metastases.

  4. Bulk physicochemical, interconnectivity, and mechanical properties of calcium phosphate cements-fibrin glue composites for bone substitute applications

    NARCIS (Netherlands)

    Lopez-Heredia, M.A.; Pattipeilohy, J.; Hsu, S.; Grykien, M.; Weijden, B. van der; Leeuwenburgh, S.C.G.; Salmon, P.; Wolke, J.G.C.; Jansen, J.A.

    2013-01-01

    Calcium phosphate cements (CPCs) and fibrin glue (FG) are used for surgical applications. Their combination is promising to create bone substitutes able to promote cell attachment and bone remodeling. This study proposes a novel approach to create CPC-FG composites by simultaneous CPC setting and FG

  5. Potential model application and planning issues

    Directory of Open Access Journals (Sweden)

    Christiane Weber

    2000-03-01

    Full Text Available Le modèle de potentiel a été et reste un modèle d'interaction spatiale utilisé pour diverses problématiques en sciences humaines, cependant l'utilisation qu'en ont fait Donnay (1997,1995,1994 et Binard (1995 en introduisant des résultats de traitement d'images comme support d'application a ouvert la voie à des applications novatrice par exemple, pour la détermination de la limite urbaine ou des hinterlands locaux. Les articulations possibles entre application du modèle de potentiel en imagerie et utilisation de plans de Système d'Information Géographique ont permis l'évaluation temporelle des tendances de développement urbain (Weber,1998. Reprenant cette idée, l'étude proposée tente d'identifier les formes de développement urbain de la Communauté urbaine de Strasbourg (CUS en tenant compte de l'occupation du sol, des caractéristiques des réseaux de communication, des réglementations urbaines et des contraintes environnementales qui pèsent sur la zone d'étude. L'état initial de l'occupation du sol, obtenu par traitements statistiques, est utilisé comme donnée d'entrée du modèle de potentiel afin d'obtenir des surfaces de potentiel associées à des caractéristiques spatiales spécifiques soit  : l'extension de la forme urbaine, la préservation des zones naturelles ou d'agricultures, ou encore les réglementations. Les résultats sont ensuite combinés et classés. Cette application a été menée pour confronter la méthode au développement réel de la CUS déterminé par une étude diachronique par comparaison d'images satellites (SPOT1986- SPOT1998. Afin de vérifier l'intérêt et la justesse de la méthode les résultats satellites ont été opposés à ceux issus de la classification des surfaces de potentiel. Les zones de développement identifiées en fonction du modèle de potentiel ont été confirmées par les résultats de l'analyse temporelle faite sur les images. Une différenciation de zones en

  6. DISTANCE LEARNING: POTENTIAL APPLICATION AND DEVELOPMENT OUTLOOK

    Directory of Open Access Journals (Sweden)

    Yulija Mihajlovna Tsarapkina

    2017-11-01

    Full Text Available The article is devoted to the actual problem of distance education potential and prospects research in the Russian education system. According to the UNESCO estimates, if the current trend continues, then the number of people with a firm desire to receive an education would increase from 165 millions to 263 millions [7, 12]. Thus 98 million qualified students worldwide will be excluded from higher education due to a shortage of university seats. The purpose of the study is to analyze the historical and present state of the problem, to identify the potential and prospects of the development in distance learning within higher education. The methodological base of the research has become common methods of pedagogical sciences: pedagogical observation, survey, questionnaire, testing, comparative analysis, pedagogical experiment. The analytical review has shown several problem areas within distance learning, such as student’s motivation while distance course learning and training efficiency as compared to full-time university training. Combination of full-time training and distance learning leads to 31% enhancement of training efficiency and shows a sustainable increase of student’s motivation.

  7. Algal Cell Factories: Approaches, Applications, and Potentials

    Directory of Open Access Journals (Sweden)

    Weiqi Fu

    2016-12-01

    Full Text Available With the advent of modern biotechnology, microorganisms from diverse lineages have been used to produce bio-based feedstocks and bioactive compounds. Many of these compounds are currently commodities of interest, in a variety of markets and their utility warrants investigation into improving their production through strain development. In this review, we address the issue of strain improvement in a group of organisms with strong potential to be productive “cell factories”: the photosynthetic microalgae. Microalgae are a diverse group of phytoplankton, involving polyphyletic lineage such as green algae and diatoms that are commonly used in the industry. The photosynthetic microalgae have been under intense investigation recently for their ability to produce commercial compounds using only light, CO2, and basic nutrients. However, their strain improvement is still a relatively recent area of work that is under development. Importantly, it is only through appropriate engineering methods that we may see the full biotechnological potential of microalgae come to fruition. Thus, in this review, we address past and present endeavors towards the aim of creating productive algal cell factories and describe possible advantageous future directions for the field.

  8. Microbial ribonucleases (RNases): production and application potential.

    Science.gov (United States)

    Hameş, E Esin; Demir, Tuğçe

    2015-12-01

    Ribonuclease (RNase) is hydrolytic enzyme that catalyzes the cleavage of phosphodiester bonds in RNA. RNases play an important role in the metabolism of cellular RNAs, such as mRNA and rRNA or tRNA maturation. Besides their cellular roles, RNases possess biological activity, cell stimulating properties, cytotoxicity and genotoxicity. Cytotoxic effect of particular microbial RNases was comparable to that of animal derived counterparts. In this respect, microbial RNases have a therapeutic potential as anti-tumor drugs. The significant development of DNA vaccines and the progress of gene therapy trials increased the need for RNases in downstream processes. In addition, RNases are used in different fields, such as food industry for single cell protein preparations, and in some molecular biological studies for the synthesis of specific nucleotides, identifying RNA metabolism and the relationship between protein structure and function. In some cases, the use of bovine or other animal-derived RNases have increased the difficulties due to the safety and regulatory issues. Microbial RNases have promising potential mainly for pharmaceutical purposes as well as downstream processing. Therefore, an effort has been given to determination of optimum fermentation conditions to maximize RNase production from different bacterial and fungal producers. Also immobilization or strain development experiments have been carried out.

  9. Nanotechnology: the scope and potential applications in orthopedic surgery.

    Science.gov (United States)

    Gavaskar, Ashok; Rojas, D; Videla, F

    2018-03-30

    Nanotechnology involves manipulation of matter measuring 1-100 nm in at least one of its dimensions at the molecular level. Engineering and manipulation of matter at the molecular level has several advantages in the field of medicine (nanomedicine) since most of the biological molecules exist and function at a nanoscale. Though promising, questions still remain on how much of this will ultimately translate into achieving better patient care. Concerns of cost-effectiveness and nanotechnology safety still remain unclear. Orthopedics is an attractive area for the application of nanotechnology since the bone, and its constituents such as hydroxyapatite, Haversian systems, and the collagen fibrils are nanocompounds. The major orthopedic applications of nanotechnology involve around (i) effective drug delivery systems for antibiotics and chemotherapeutic agents, (ii) surface preparation of implants and prosthesis to improve osteointegration and reduce biofilm formation, (iii) controlled drug eluting systems to combat implant-related infections, (iv) tissue engineering for scaffolds preparation to deal with bone and cartilage defects, and (v) diagnostic applications in the field of oncology and musculoskeletal infections.

  10. Differentiation potential of menstrual blood- versus bone marrow-stem cells into glial-like cells.

    Science.gov (United States)

    Azedi, Fereshteh; Kazemnejad, Somaieh; Zarnani, Amir Hassan; Behzadi, Gila; Vasei, Mohammad; Khanmohammadi, Manijeh; Khanjani, Sayeh; Edalatkhah, Haleh; Lakpour, Niknam

    2014-05-01

    Menstrual blood is easily accessible, renewable, and inexpensive source of stem cells that have been interested for cell therapy of neurodegenerative diseases. In this study, we showed conversion of menstrual blood stem cells (MenSCs) into clonogenic neurosphere- like cells (NSCs), which can be differentiated into glial-like cells. Moreover, differentiation potential of MenSCs into glial lineage was compared with bone marrow stem cells (BMSCs). Differentiation potential of individual converted NSCs derived from MenSCs or BMSCs into glial-like cells was investigated using immunofluorescence staining and real-time polymerase chain reaction.The fibroblastic morphology of both MenSCs and BMSCs was turned into NSCs shape during first step of differentiation. NSCs derived from both BMSCs and MenSCs expressed higher levels of Olig-2 and Nestin markers compared to undifferentiated cells. The expression levels of myelin basic protein (MBP) mRNA up regulated only in BMSCs-NSCs no in MenSCs-NSCs. However, outgrowth of individual NSCs derived from both MenSCs and BMSCs into glial-like cells led to significant up regulation of glial fibrillary acidic protein,Olig-2 and MBP at mRNA and protein level accompanied with down regulation of Nestin protein.This is the first study demonstrating that MenSCs can be converted to NSCs with differentiation ability into glial-like cells. Accumulative data show different expression pattern of glial markers in differentiated MenSCs compared to BMSCs. The comparable differentiation potential, more accessibility and no invasive technique for sample collection of MenSCs in comparison with BMSCs introduce MenSCs as an apt, consistent and safe alternative to BMSCs for cell therapy of neurodegenerative diseases. © 2014 International Federation for Cell Biology.

  11. Potential Spermatogenesis Recovery with Bone Marrow Mesenchymal Stem Cells in an Azoospermic Rat Model

    Directory of Open Access Journals (Sweden)

    Deying Zhang

    2014-07-01

    Full Text Available Non-obstructive azoospermia is the most challenging type of male infertility. Stem cell based therapy provides the potential to enhance the recovery of spermatogenesis following cancer therapy. Bone marrow-derived mesenchymal stem cells (BMSCs possess the potential to differentiate or trans-differentiate into multi-lineage cells, secrete paracrine factors to recruit the resident stem cells to participate in tissue regeneration, or fuse with the local cells in the affected region. In this study, we tested whether spermatogenically-induced BMSCs can restore spermatogenesis after administration of an anticancer drug. Allogeneic BMSCs were co-cultured in conditioned media derived from cultured testicular Sertoli cells in vitro, and then induced stem cells were transplanted into the seminiferous tubules of a busulfan-induced azoospermatic rat model for 8 weeks. The in vitro induced BMSCs exhibited specific spermatogonic gene and protein markers, and after implantation the donor cells survived and located at the basement membranes of the recipient seminiferous tubules, in accordance with what are considered the unique biological characteristics of spermatogenic stem cells. Molecular markers of spermatogonial stem cells and spermatogonia (Vasa, Stella, SMAD1, Dazl, GCNF, HSP90α, integrinβ1, and c-kit were expressed in the recipient testis tissue. No tumor mass, immune response, or inflammatory reaction developed. In conclusion, BMSCs might provide the potential to trans-differentiate into spermatogenic-like-cells, enhancing endogenous fertility recovery. The present study indicates that BMSCs might offer alternative treatment for the patients with azoospermatic infertility after cancer chemotherapy.

  12. Biosilica-glass formation using enzymes from sponges [silicatein]: Basic aspects and application in biomedicine [bone reconstitution material and osteoporosis

    Science.gov (United States)

    Wang, Shun-Feng; Wang, Xiao-Hong; Gan, Lu; Wiens, Matthias; Schröder, Heinz C.; Müller, Werner E. G.

    2011-09-01

    In the last 15 years biomineralization, in particular biosilicification (i.e., the formation of biogenic silica, SiO2), has become an exciting source of inspiration for the development of novel bionic approaches, following "Nature as model". Among the silica forming organisms there are the sponges that have the unique property to catalyze their silica skeletons by a specific enzyme termed silicatein. In the present review we summarize the present state of knowledge on silicatein-mediated "biosilica" formation in marine sponges, the involvement of further molecules in silica metabolism and their potential application in biomedicine. Recent advancements in the production of bone replacement material and in the potential use as a component in the treatment of osteoporosis are highlighted.

  13. Geothermal energy in Yugoslavia, potentials and applications

    International Nuclear Information System (INIS)

    Boreli, F.; Paradjanin, Lj.; Stankovic, Srb.

    2002-01-01

    This paper promotes the use of Geothermal energy (GTE) in Serbia, and argues that while GTE is both a viable and environmentally friendly energy source, as demonstrated elsewhere in the world, there is also a multitude of opportunities in this region, and the local knowledge and capabilities required for implementing the GTE plants. First, a general introduction to GTE in is given. The basis of GTE is the thermal energy accumulated in fluids and rocks masses in the Earth's Crust. The main GTE advantage compared to the traditional energy sources like thermo-electric plants is the absence of environmental deterioration, however GTE also has advantages compared to other NARES, as the GT sources are permanently available and independent of weather conditions. Worldwide energy potential of GTE is huge, as the reduction of Earth Crust temperature for just 0.1 deg. C would give enough Energy to produce Electrical Energy, at the present dissipation level, for the next 15,000 years. An overview of the regions in Yugoslavia which have a high GTE potential is given. There are two distinct regions with higher GTE values in Serbia: the first is a part of the South Panonian basin including Vojvodina, with Macva and Yu-part along Danube and Morava rivers. This is a sedimental part of the Tercier's Panonic Sea 'Parathetis', with partial depression and Backa subsupression, and is well investigated due to oil and gas holeboring. The second region includes Central and Southern part of Serbia, south from the Panonia basin, with pretercier's and tercier's magmatic volcanic intrusions, which produce a very high and stable thermal flux. This Region is rich in GT-warm water springs with stable yields, and includes 217 locations with 970 natural springs with temperature above 20 deg. C. These compare very favorably with international locations where GTE is exploited. GTE can be used for Electric Energy production using corresponding heat pump systems, for house heating and warm water

  14. Comparative study of the chondrogenic potential of human bone marrow stromal cells, neonatal chondrocytes and adult chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Sushmita [Biomaterials and Tissue Engineering Group, Leeds Dental Institute, University of Leeds, LS29LU (United Kingdom); Kirkham, Jennifer [Biomineralisation Group, Leeds Dental Institute, University of Leeds, LS29LU (United Kingdom); NIHR Leeds Musculoskeletal Biomedical Research Unit, University of Leeds, Chapel Allerton Hospital, Leeds LS74SA (United Kingdom); Wood, David [Biomaterials and Tissue Engineering Group, Leeds Dental Institute, University of Leeds, LS29LU (United Kingdom); Curran, Stephen [Smith and Nephew Research Centre, YO105DF (United Kingdom); Yang, Xuebin, E-mail: X.B.Yang@leeds.ac.uk [Biomaterials and Tissue Engineering Group, Leeds Dental Institute, University of Leeds, LS29LU (United Kingdom); NIHR Leeds Musculoskeletal Biomedical Research Unit, University of Leeds, Chapel Allerton Hospital, Leeds LS74SA (United Kingdom)

    2010-10-22

    Research highlights: {yields} This study has characterised three different cell types under conditions similar to those used for autologous chondrocyte implantation (ACI) for applications in cartilage repair/regeneration. {yields} Compared for the first time the chondrogenic potential of neonatal chondrocytes with human bone marrow stromal cells (HBMSCs) and adult chondrocytes. {yields} Demonstrated that adult chondrocytes hold greatest potential for use in ACI based on their higher proliferation rates, lower alkaline phosphatise activity and enhanced expression of chondrogenic genes. {yields} Demonstrated the need for chondroinduction as a necessary pre-requisite to efficient chondrogenesis in vitro and, by extrapolation, for cell based therapy (e.g. ACI or cartilage tissue engineering). -- Abstract: Cartilage tissue engineering is still a major clinical challenge with optimisation of a suitable source of cells for cartilage repair/regeneration not yet fully addressed. The aims of this study were to compare and contrast the differences in chondrogenic behaviour between human bone marrow stromal cells (HBMSCs), human neonatal and adult chondrocytes to further our understanding of chondroinduction relative to cell maturity and to identify factors that promote chondrogenesis and maintain functional homoeostasis. Cells were cultured in monolayer in either chondrogenic or basal medium, recapitulating procedures used in existing clinical procedures for cell-based therapies. Cell doubling time, morphology and alkaline phosphatase specific activity (ALPSA) were determined at different time points. Expression of chondrogenic markers (SOX9, ACAN and COL2A1) was compared via real time polymerase chain reaction. Amongst the three cell types studied, HBMSCs had the highest ALPSA in basal culture and lowest ALPSA in chondrogenic media. Neonatal chondrocytes were the most proliferative and adult chondrocytes had the lowest ALPSA in basal media. Gene expression analysis revealed

  15. Comparative study of the chondrogenic potential of human bone marrow stromal cells, neonatal chondrocytes and adult chondrocytes

    International Nuclear Information System (INIS)

    Saha, Sushmita; Kirkham, Jennifer; Wood, David; Curran, Stephen; Yang, Xuebin

    2010-01-01

    Research highlights: → This study has characterised three different cell types under conditions similar to those used for autologous chondrocyte implantation (ACI) for applications in cartilage repair/regeneration. → Compared for the first time the chondrogenic potential of neonatal chondrocytes with human bone marrow stromal cells (HBMSCs) and adult chondrocytes. → Demonstrated that adult chondrocytes hold greatest potential for use in ACI based on their higher proliferation rates, lower alkaline phosphatise activity and enhanced expression of chondrogenic genes. → Demonstrated the need for chondroinduction as a necessary pre-requisite to efficient chondrogenesis in vitro and, by extrapolation, for cell based therapy (e.g. ACI or cartilage tissue engineering). -- Abstract: Cartilage tissue engineering is still a major clinical challenge with optimisation of a suitable source of cells for cartilage repair/regeneration not yet fully addressed. The aims of this study were to compare and contrast the differences in chondrogenic behaviour between human bone marrow stromal cells (HBMSCs), human neonatal and adult chondrocytes to further our understanding of chondroinduction relative to cell maturity and to identify factors that promote chondrogenesis and maintain functional homoeostasis. Cells were cultured in monolayer in either chondrogenic or basal medium, recapitulating procedures used in existing clinical procedures for cell-based therapies. Cell doubling time, morphology and alkaline phosphatase specific activity (ALPSA) were determined at different time points. Expression of chondrogenic markers (SOX9, ACAN and COL2A1) was compared via real time polymerase chain reaction. Amongst the three cell types studied, HBMSCs had the highest ALPSA in basal culture and lowest ALPSA in chondrogenic media. Neonatal chondrocytes were the most proliferative and adult chondrocytes had the lowest ALPSA in basal media. Gene expression analysis revealed a difference in the

  16. Predictive modeling: potential application in prevention services.

    Science.gov (United States)

    Wilson, Moira L; Tumen, Sarah; Ota, Rissa; Simmers, Anthony G

    2015-05-01

    In 2012, the New Zealand Government announced a proposal to introduce predictive risk models (PRMs) to help professionals identify and assess children at risk of abuse or neglect as part of a preventive early intervention strategy, subject to further feasibility study and trialing. The purpose of this study is to examine technical feasibility and predictive validity of the proposal, focusing on a PRM that would draw on population-wide linked administrative data to identify newborn children who are at high priority for intensive preventive services. Data analysis was conducted in 2013 based on data collected in 2000-2012. A PRM was developed using data for children born in 2010 and externally validated for children born in 2007, examining outcomes to age 5 years. Performance of the PRM in predicting administratively recorded substantiations of maltreatment was good compared to the performance of other tools reviewed in the literature, both overall, and for indigenous Māori children. Some, but not all, of the children who go on to have recorded substantiations of maltreatment could be identified early using PRMs. PRMs should be considered as a potential complement to, rather than a replacement for, professional judgment. Trials are needed to establish whether risks can be mitigated and PRMs can make a positive contribution to frontline practice, engagement in preventive services, and outcomes for children. Deciding whether to proceed to trial requires balancing a range of considerations, including ethical and privacy risks and the risk of compounding surveillance bias. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  17. Regulation of Sclerostin Expression in Multiple Myeloma by Dkk-1: A Potential Therapeutic Strategy for Myeloma Bone Disease.

    Science.gov (United States)

    Eda, Homare; Santo, Loredana; Wein, Marc N; Hu, Dorothy Z; Cirstea, Diana D; Nemani, Neeharika; Tai, Yu-Tzu; Raines, Sarah E; Kuhstoss, Stuart Allen; Munshi, Nikhil C; Kronenberg, Henry M; Raje, Noopur S

    2016-06-01

    Sclerostin is a potent inhibitor of osteoblastogenesis. Interestingly, newly diagnosed multiple myeloma (MM) patients have high levels of circulating sclerostin that correlate with disease stage and fractures. However, the source and impact of sclerostin in MM remains to be defined. Our goal was to determine the role of sclerostin in the biology of MM and its bone microenvironment as well as investigate the effect of targeting sclerostin with a neutralizing antibody (scl-Ab) in MM bone disease. Here we confirm increased sclerostin levels in MM compared with precursor disease states like monoclonal gammopathy of undetermined significance (MGUS) and smoldering MM. Furthermore, we found that a humanized MM xenograft mouse model bearing human MM cells (NOD-SCID.CB17 male mice injected intravenously with 2.5 million of MM1.S-Luc-GFP cells) demonstrated significantly higher concentrations of mouse-derived sclerostin, suggesting a microenvironmental source of sclerostin. Associated with the increased sclerostin levels, activated β-catenin expression levels were lower than normal in MM mouse bone marrow. Importantly, a high-affinity grade scl-Ab reversed osteolytic bone disease in this animal model. Because scl-Ab did not demonstrate significant in vitro anti-MM activity, we combined it with the proteasome inhibitor carfilzomib. Our data demonstrated that this combination therapy significantly inhibited tumor burden and improved bone disease in our in vivo MM mouse model. In agreement with our in vivo data, sclerostin expression was noted in marrow stromal cells and osteoblasts of MM patient bone marrow samples. Moreover, MM cells stimulated sclerostin expression in immature osteoblasts while inhibiting osteoblast differentiation in vitro. This was in part regulated by Dkk-1 secreted by MM cells and is a potential mechanism contributing to the osteoblast dysfunction noted in MM. Our data confirm the role of sclerostin as a potential therapeutic target in MM bone disease

  18. Bisphosphonate-Related Osteonecrosis of the Jaw Bone: Radiological Pattern and the Potential Role of CBCT in Early Diagnosis

    Directory of Open Access Journals (Sweden)

    James Olutayo

    2010-04-01

    Full Text Available Objectives: To systematize the clinico-radiological symptoms and course of bisphosphonate-related osteonecrosis of jaw bone and to evaluate the diagnostic potential of various radiological techniques to detect mild osteonecrosis in each stage of the disease.Material and Methods: The sample consisted of 22 patients previously diagnosed with extraoral malignant disease. Diagnosis was based on a clinical examination in conjunction to digital panoramic radiography and cone beam computed tomography (CBCT. Two dentomaxillofacial radiologists reviewed all images.Results: Twenty patients showed mandibular involvement clinically, while two others had a maxillary involvement. Four stages of the disease were proposed based on the clinico-radiological findings. Subclinical cortical and lamina dura thickening was detected with only three-dimensional CBCT and periapical images, while ulceration and cortical bone thickening was detected only by three-dimensional CBCT. Mixed sclerotic, lytic bone destruction involving alveolar and basal bone with or without encroachment on the mandibular canal, pathological mandibular fractures were detected by two-dimensional panoramic and three-dimensional CBCT images. Other findings are non healing extraction sockets, periapical radiolucencies, osteolysis, sequestra, oroantral fistula, and periosteal new bone formation.Conclusions: The present study showed that bisphosphonate-related osteonecrosis of jaw bone occurs in four distinct clinico-radiological stages. For mild cases, panoramic image diagnosis was much less obvious, whereas cone beam computed tomography was able to fully characterise the bony lesions and describe their extent and involvement of neighbouring structures in all cases. Thus cone beam computed tomography might better contribute to the prevention of bisphosphonate-related osteonecrosis of jaw bone as well to the disease management.

  19. Histologic evaluation of bone healing capacity following application of inorganic bovine bone and a new allograft material in rabbit calvaria.

    Directory of Open Access Journals (Sweden)

    Mojgan Paknejad

    2015-02-01

    Full Text Available Considering the importance of bone augmentation prior to implant placement in order to obtain adequate bone quality and quantity, many studies have been conducted to evaluate different techniques and materials regarding new bone formation. In this study, we investigated the bone healing capacity of two different materials deproteinized bovine bone mineral (DBBM with the trade name of Bio-Oss and demineralized freeze-dried bone allograft (DFDBA with the trade name of DynaGraft.This randomized blinded prospective study was conducted on twelve New Zealand white rabbits. Three cranial defects with an equal diameter were created on their calvarium. Subsequently, they were distributed into three groups: 1. The control group without any treatment; 2. The Bio-Oss group; 3. The DynaGraft group. After 30 days, the animals were sacrificed for histologic and histomorphometric analysis.Substantial new bone formation was observed in both groups. DynaGraft: 56/1 % ± 15/1 and Bio-Oss: 53/55 % ± 13/5 compared to the control group: 28/6 % ± 11/2. All groups showed slight inflammation and a small amount of residual biomaterial was observed.Considerable new bone formation was demonstrated in both DynaGraft and Bio-Oss groups in comparison with the control group. Both materials are considered biocompatible regarding the negligible foreign body reaction.

  20. Morphological features of the macerated cranial bones registered by the 3D vision system for potential use in forensic anthropology.

    Science.gov (United States)

    Skrzat, Janusz; Sioma, Andrzej; Kozerska, Magdalena

    2013-01-01

    In this paper we present potential usage of the 3D vision system for registering features of the macerated cranial bones. Applied 3D vision system collects height profiles of the object surface and from that data builds a three-dimensional image of the surface. This method appeared to be accurate enough to capture anatomical details of the macerated bones. With the aid of the 3D vision system we generated images of the surface of the human calvaria which was used for testing the system. Performed reconstruction visualized the imprints of the dural vascular system, cranial sutures, and the three-layer structure of the cranial bones observed in the cross-section. We figure out that the 3D vision system may deliver data which can enhance estimation of sex from the osteological material.

  1. TU-CD-BRA-11: Application of Bone Suppression Technique to Inspiratory/expiratory Chest Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, R; Sanada, S [Kanazawa University, Kanazawa, Ishikawa (Japan); Sakuta, K; Kawashima, H [Kanazawa University Hospital, Kanazawa, Ishikawa (Japan); Kishitani, Y [TOYO Corporation, Chuoh-ku, Tokyo (Japan)

    2015-06-15

    with the bone suppression technique has potential for predicting local lung function on the basis of dynamic analysis of pulmonary markings. This work was partially supported by Nakatani Foundation, Grant-in-aid for Scientific Research (C) of Ministry of Education, Culture, Sports, Science and Technology, JAPAN (Grant number : 24601007), and Nakatani Foundation, Mitsubishi Foundation, and the he Mitani Foundation for Research and Development. Yasushi Kishitani is a staff of TOYO corporation.

  2. Metallic bionanocatalysts: potential applications as green catalysts and energy materials.

    Science.gov (United States)

    Macaskie, Lynne E; Mikheenko, Iryna P; Omajai, Jacob B; Stephen, Alan J; Wood, Joseph

    2017-09-01

    Microbially generated or supported nanocatalysts have potential applications in green chemistry and environmental application. However, precious (and base) metals biorefined from wastes may be useful for making cheap, low-grade catalysts for clean energy production. The concept of bionanomaterials for energy applications is reviewed with respect to potential fuel cell applications, bio-catalytic upgrading of oils and manufacturing 'drop-in fuel' precursors. Cheap, effective biomaterials would facilitate progress towards dual development goals of sustainable consumption and production patterns and help to ensure access to affordable, reliable, sustainable and modern energy. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  3. Multifunctional nano-hydroxyapatite and alginate/gelatin based sticky gel composites for potential bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yurong; Yu, Juhong [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, National Engineering Lab of Textile Fiber Materials & Processing Technology, College of Materials and Textile, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Kundu, Subhas C. [Department of Biotechnology, Indian Institute of Technology (IIT) Kharagpur, West Bengal 721302 (India); Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714 (Korea, Republic of); Yao, Juming, E-mail: yaoj@zstu.edu.cn [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, National Engineering Lab of Textile Fiber Materials & Processing Technology, College of Materials and Textile, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

    2016-09-15

    To improve the fixations of the implant and implant-bone integration after joint arthroplasty from locally preventing inflammation and promoting the bone regeneration, we design a multifunctional biomaterial consisting of recombinant human bone morphogenetic protein 2 (rhBMP-2) and antibiotic loaded nano-hydroxyapatite with an alginate/gelatin sticky gel. We investigate its role for the prevention of the inflammation and possibility of inducing a new bone growth along with its adhesive ability. The stickiness exists in the composite, which may help to fix itself on the bone fracture surface. The composite sustains the antibacterial effect and promotes the proliferation and differentiation of MG63 cells in vitro. In vivo experimentation also shows that the composite gel has a role for the reduction of inflammation. It enhances the formation of new bone and blood vessels compared to both the sole rhBMP-2 and non-rhBMP-2/antibiotic loaded composite gels. The multifunctional composite provides a promising material for the prosthetic and bone tissue regeneration. - Highlights: • Multifunctional nanohydroxyapatite composite is fabricated. • The composite consists of nHAP, growth factor, antibiotic and alginate/gelatin gel. • The composite shows antibacterial effect and good cytocompatibility. • No adverse effect to the cells tested in vitro and in vivo.

  4. Regulation of sclerostin expression in multiple myeloma by Dkk-1; a potential therapeutic strategy for myeloma bone disease

    Science.gov (United States)

    Eda, Homare; Santo, Loredana; Wein, Marc N.; Hu, Dorothy Z.; Cirstea, Diana D.; Nemani, Neeharika; Tai, Yu-Tzu; Raines, Sarah E.; Kuhstoss, Stuart Allen; Munshi, Nikhil C.; Kronenberg, Henry M.; Raje, Noopur S.

    2016-01-01

    Sclerostin is a potent inhibitor of osteoblastogenesis. Interestingly, newly diagnosed multiple myeloma (MM) patients have high levels of circulating sclerostin that correlate with disease stage and fractures. However, the source and impact of sclerostin in MM remains to be defined. Our goal was to determine the role of sclerostin in the biology of MM and its bone microenvironment as well as investigate the effect of targeting sclerostin with a neutralizing antibody (scl-Ab) in MM bone disease. Here we confirm increased sclerostin levels in MM compared to precursor disease states like Monoclonal Gammopathy of Undetermined Significance (MGUS) and smoldering MM. Furthermore, we found that a humanized MM xenograft mouse model bearing human MM cells (NOD-SCID.CB17 male mice injected intravenously with 2.5 million of MM1.S-Luc-GFP cells) demonstrated significantly higher concentrations of mouse-derived sclerostin, suggesting a microenvironmental source of sclerostin. Associated with the increased sclerostin levels, activated β-catenin expression levels were lower than normal in MM mouse bone marrow. Importantly, a high affinity grade scl-Ab reversed osteolytic bone disease in this animal model. Because scl-Ab did not demonstrate significant in vitro anti-MM activity, we combined it with the proteasome inhibitor, carfilzomib. Our data demonstrated that this combination therapy significantly inhibited tumor burden and improved bone disease in our in vivo MM mouse model. In agreement with our in vivo data, sclerostin expression was noted in marrow stromal cells and osteoblasts of MM patient BM samples. Moreover, MM cells stimulated sclerostin expression in immature osteoblasts while inhibiting osteoblast differentiation in vitro. This was in part regulated by Dkk-1 secreted by MM cells and is a potential mechanism contributing to the osteoblast dysfunction noted in MM. Our data confirms the role of sclerostin as a potential therapeutic target in MM bone disease, and

  5. The transient receptor potential channel TRPV6 is dynamically expressed in bone cells but is not crucial for bone mineralization in mice

    NARCIS (Netherlands)

    Eerden, B.C.J.; Weissgerber, P.; Fratzl-Zelman, N.; Olausson, J.; Hoenderop, J.G.J.; Schreuders-Koedam, M.; Eijken, M.; Roschger, P.; de Vries, T.J.; Chiba, H.; Klaushofer, K.; Flockerzi, V.; Bindels, R.J.M.; Freichel, M.; Leeuwen, J.P.T.M.

    2012-01-01

    Bone is the major store for Ca2+ in the body and plays an important role in Ca2+ homeostasis. During bone formation and resorption Ca2+ must be transported to and from bone by osteoblasts and osteoclasts, respectively. However, little is known about the Ca2+ transport machinery in these bone cells.

  6. The transient receptor potential channel TRPV6 is dynamically expressed in bone cells but is not crucial for bone mineralization in mice.

    NARCIS (Netherlands)

    Eerden, B.C. van der; Weissgerber, P.; Fratzl-Zelman, N.; Olausson, J.; Hoenderop, J.G.J.; Schreuders-Koedam, M.; Eijken, M.; Roschger, P.; Vries, T.J. de; Chiba, H.; Klaushofer, K.; Flockerzi, V.; Bindels, R.J.M.; Freichel, M.; Leeuwen, J.P. van

    2012-01-01

    Bone is the major store for Ca(2+) in the body and plays an important role in Ca(2+) homeostasis. During bone formation and resorption Ca(2+) must be transported to and from bone by osteoblasts and osteoclasts, respectively. However, little is known about the Ca(2+) transport machinery in these bone

  7. Application of continuous-wave terahertz computed tomography for the analysis of chicken bone structure

    Science.gov (United States)

    Li, Bin; Wang, Dayong; Rong, Lu; Zhai, Changchao; Wang, Yunxin; Zhao, Jie

    2018-02-01

    Terahertz (THz) radiation is able to penetrate many different types of nonpolar and nonmetallic materials without the damaging effects of x-rays. THz technology can be combined with computed tomography (CT) to form THz CT, which is an effective imaging method that is used to visualize the internal structure of a three-dimensional sample as cross-sectional images. Here, we reported an application of THz as the radiation source in CT imaging by replacing the x-rays. In this method, the sample cross section is scanned in all translation and rotation directions. Then, the projection data are reconstructed using a tomographic reconstruction algorithm. Two-dimensional (2-D) cross-sectional images of the chicken ulna were obtained through the continuous-wave (CW) THz CT system. Given by the difference of the THz absorption of different substances, the compact bone and spongy bone inside the chicken ulna are structurally distinguishable in the 2-D cross-sectional images. Using the filtered back projection algorithm, we reconstructed the projection data of the chicken ulna at different projection angle intervals and found that the artifacts and noise in the images are strikingly increased when the projection angle intervals become larger, reflected by the blurred boundary of the compact bone. The quality and fidelity of the 2-D cross-sectional images could be substantially improved by reducing the projection angle intervals. Our experimental data demonstrated a feasible application of the CW THz CT system in biological imaging.

  8. Application of bioabsorbable screw fixation for anterior cervical decompression and bone grafting

    Directory of Open Access Journals (Sweden)

    Bo Zhao

    Full Text Available OBJECTIVES: To examine the application of bioabsorbable screws for anterior cervical decompression and bone grafting fixation and to study their clinical effects in the treatment of cervical spondylosis. METHODS: From March 2007 to September 2012, 56 patients, 36 males and 20 females (38-79 years old, average 58.3±9.47 years, underwent a novel operation. Grafts were fixed by bioabsorbable screws (PLLA, 2.7 mm in diameter after anterior decompression. The bioabsorbable screws were inserted from the midline of the graft bone to the bone surface of the upper and lower vertebrae at 45 degree angles. Patients were evaluated post-operatively to observe the improvement of symptoms and evaluate the fusion of the bone. The Japanese Orthopaedic Association (JOA score was used to evaluate the recovery of neurological functions. RESULTS: All screws were successfully inserted, with no broken screws. The rate of symptom improvement was 87.5%. All of the grafts fused well with no extrusion. The average time for graft fusion was 3.8±0.55 months (range 3-5 months. Three-dimensional reconstruction of CT scans demonstrated that the grafts fused with adjacent vertebrae well and that the screws were absorbed as predicted. The MRI findings showed that the cerebrospinal fluid was unobstructed. No obvious complications appeared in any of the follow-up evaluations. CONCLUSIONS: Cervical spondylosis with one- or two-level involvement can be effectively treated by anterior decompression and bone grafting with bioabsorbable screw fixation. This operative method is safe and can avoid the complications induced by metal implants.

  9. Physical and mechanical properties evaluation of Acropora palmata coralline species for bone substitution applications.

    Science.gov (United States)

    Alvarez, K; Camero, S; Alarcón, M E; Rivas, A; González, G

    2002-05-01

    The search for ideal materials for bone substitution has been a challenge for many decades. Numerous natural and synthetic materials have been studied. For this application, exoskeletons of coral have been considered a good alternative given its tendency to resorption, biocompatibility and similarity to the mineral bone phase. Very few studies of these materials consider a detailed analysis of the structure-property relationship. The purpose of this work was to carry out the microstructural characterization of a coralline species named Acropora palmata and the determination of the mechanical and physico-chemical properties. Measurements of hardness, compressive strength, bulk density and apparent porosity were performed. From these results it was determined that this marine coral species could be an alternative xenograft due to its mechanical properties and osteoconductive nature.

  10. A simplified application (APP) for the parametric design of screw-plate fixation of bone fractures.

    Science.gov (United States)

    Chung, Chen-Yuan

    2018-01-01

    Screw and plate fixation is commonly used to treat bone fractures. A prototype application (APP) for presurgical simulation was developed and validated by comparing it with current analytical approach and other models. In this APP, alternative plate designs and materials to limit the effects of stress shielding could be tested. In addition, the number and position of screws and the gap between bone and plate that achieved acceptable stability were predicted. The fixation stability providing a situation of interfragmentary strain between 2% and 10% is necessary for callus formation. However, improving the fixation stability leads to a stress shielding effect. The simultaneous alleviation of stress shielding and maintenance of stability are important in fracture healing. In this study, the feasibility of creating a specialized APP to evaluate different screw-plate configurations for diaphyseal femoral fractures was investigated. The ultimate goal is to extend this technique to computer-assisted preoperative planning for orthopedic surgery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Bone and skeletal muscle: Key players in mechanotransduction and potential overlapping mechanisms.

    Science.gov (United States)

    Goodman, Craig A; Hornberger, Troy A; Robling, Alexander G

    2015-11-01

    The development and maintenance of skeletal muscle and bone mass is critical for movement, health and issues associated with the quality of life. Skeletal muscle and bone mass are regulated by a variety of factors that include changes in mechanical loading. Moreover, bone mass is, in large part, regulated by muscle-derived mechanical forces and thus by changes in muscle mass/strength. A thorough understanding of the cellular mechanism(s) responsible for mechanotransduction in bone and skeletal muscle is essential for the development of effective exercise and pharmaceutical strategies aimed at increasing, and/or preventing the loss of, mass in these tissues. Thus, in this review we will attempt to summarize the current evidence for the major molecular mechanisms involved in mechanotransduction in skeletal muscle and bone. By examining the differences and similarities in mechanotransduction between these two tissues, it is hoped that this review will stimulate new insights and ideas for future research and promote collaboration between bone and muscle biologists.(1). Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Natural Products from Chinese Medicines with Potential Benefits to Bone Health

    Directory of Open Access Journals (Sweden)

    Chun-Tao Che

    2016-02-01

    Full Text Available Osteoporosis is a progressive, systemic bone disorder characterized by loss of bone mass and microstructure, leading to reduced bone strength and increased risk of fracture. It is often associated with reduced quality of life and other medical complications. The disease is common in the aging population, particularly among postmenopausal women and patients who receive long-term steroidal therapy. Given the rapid growth of the aging population, increasing life expectancy, the prevalence of bone loss, and financial burden to the healthcare system and individuals, demand for new therapeutic agents and nutritional supplements for the management and promotion of bone health is pressing. With the advent of global interest in complementary and alternative medicine and natural products, Chinese medicine serves as a viable source to offer benefits for the improvement and maintenance of bone health. This review summarizes the scientific information obtained from recent literatures on the chemical ingredients of Chinese medicinal plants that have been reported to possess osteoprotective and related properties in cell-based and/or animal models. Some of these natural products (or their derivatives may become promising leads for development into dietary supplements or therapeutic drugs.

  13. External fixation of femoral defects in athymic rats: Applications for human stem cell implantation and bone regeneration

    Directory of Open Access Journals (Sweden)

    Terasa Foo

    2013-01-01

    Full Text Available An appropriate animal model is critical for the research of stem/progenitor cell therapy and tissue engineering for bone regeneration in vivo. This study reports the design of an external fixator and its application to critical-sized femoral defects in athymic rats. The external fixator consists of clamps and screws that are readily available from hardware stores as well as Kirschner wires. A total of 35 rats underwent application of the external fixator with creation of a 6-mm bone defect in one femur of each animal. This model had been used in several separate studies, including implantation of collagen gel, umbilical cord blood mesenchymal stem cells, endothelial progenitor cells, or bone morphogenetic protein-2. One rat developed fracture at the proximal pin site and two rats developed deep tissue infection. Pin loosening was found in nine rats, but it only led to the failure of external fixation in two animals. In 8 to 10 weeks, various degrees of bone growth in the femoral defects were observed in different study groups, from full repair of the bone defect with bone morphogenetic protein-2 implantation to fibrous nonunion with collagen gel implantation. The external fixator used in these studies provided sufficient mechanical stability to the bone defects and had a comparable complication rate in athymic rats as in immunocompetent rats. The external fixator does not interfere with the natural environment of a bone defect. This model is particularly valuable for investigation of osteogenesis of human stem/progenitor cells in vivo.

  14. The potentials of ICT application to increased relevance and ...

    African Journals Online (AJOL)

    The potentials of ICT application to increased relevance and sustainability of University Library Services in Nigeria. ... in Kenneth Dike library, University of Ibadan and University of Lagos Libraries and library search of recent literature on ICT application and marketing of ICT based services in Nigerian University libraries.

  15. Profiling application potential for alkali treated sisal fiber ...

    African Journals Online (AJOL)

    Profiling application potential for alkali treated sisal fiber-polypropylene composite in Ashby material-property plots. ... International Journal of Engineering, Science and Technology ... The effect of alkali treatment on sisal fiber from the plant agave sisalana in appropriation for composite material application is presented.

  16. A Methodology for Screening Potential Artificial Intelligence Applications

    Science.gov (United States)

    1988-07-01

    trryv’ rr P ’r ( l Ft COPY ..10 nr MEcp AFWAL-TR-.8-1083 I I A METHODOLOGY FOR SCREENING POTENTIAL ARTIFICIAL ~ INTELLIGENCE APPLICATIONS S Lt Eric N...Hanson Artificial Intelligence Applications Office JULY 1088 PROCEEDINGS APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED (, ELECTC-, NOV 2...BEEN REVIEWED AND IS APPROVED FOR PUBLICATION. ERIC N. HANSO’, lT, USAF WILLIAM R. BAKER Technical Director Chief, Artificial Intelligence Applications Office

  17. The potential of chitosan combined with chicken shank collagen as scaffold on bone defect regeneration process in Rattus norvegicus

    Directory of Open Access Journals (Sweden)

    Fitria Rahmitasari

    2016-12-01

    Full Text Available Background: In the field of dentistry, alveolar bone damage can be caused by periodontal disease, traumatic injury due to tooth extraction, cyst enucleation, and tumor surgery. One of the ways to regenerate the bone defect is using graft scaffold. Thus, combination of chitosan and collagen can stimulate osteogenesis. Purpose: The aim of this study was to examine the potential of chitosan combined with chicken shank collagen on bone defect regeneration process. Method: Twelve Rattus norvegicus were prepared as animal models in this research. A bone defect was intentionally created at both of the right and left femoral bones of the models. Next, 24 samples were divided into four groups, namely Group 1 using chitosan – collagen scaffold (50:50, Group 2 using chitosan collagen-scaffold (80:20, Group 3 using chitosan scaffold only, and Control Group using 3% CMC-Na. On 14th day, those animals were sacrificed, and histopathological anatomy examination was conducted to observe osteoclast cells. In addition, immunohistochemistry examination was also performed to observe RANKL expressions. Result: There was a significant difference in RANKL expressions among the groups, except between Group 3 using chitosan scaffold only and control group (p value > 0.05. The highest expression of RANKL was found in Group 1 with chitosan – collagen scaffold (50:50, followed by Group 2 with chitosan-collagen scaffold (80:20. Moreover, there was also a significant difference in osteoclast generation, except between Group 1 using chitosan – collagen scaffold (50:50 and Group 2 using chitosan-collagen scaffold (80:20, p value 0.05. Less osteoclast was found in the groups using chitosan – collagen scaffold (Group 1 and Group 2. Conclusion: Combination of chitosan and chicken shank collagen scaffold can improve regeneration process of bone defect in Rattus novergicus animals through increasing of RANKL expressions, and decreasing of osteoclast.

  18. Osteoinductive potential and bone-bonding ability of ProRoot MTA, MTA Plus and Biodentine in rabbit intramedullary model: Microchemical characterization and histological analysis.

    Science.gov (United States)

    Gandolfi, M G; Iezzi, G; Piattelli, A; Prati, C; Scarano, A

    2017-05-01

    To study the in vivo osteoinductive potential, bone-bonding ability (bioactivity) and bone biomineralization of current hydraulic calcium silicate cements used as graft materials and placed in contact with medullary bone. ProRoot MTA, MTA Plus and Biodentine were used to fill surgical bone defects (2-mm diameter through the entire cortical thickness to reach the medullary bone) in the tibia of mature male rabbits. Tibiae were retrieved after 30days and submitted to histological analysis and microchemical characterization using Optical Microscopy (OM) and Environmental Scanning Electron Microscopy with Energy Dispersive X-ray analysis (ESEM-EDX). Bone neoformation and histomorphometric evaluations, degree of mineralization (by Ca/P, Ca/N and P/N ratios) and the diffusion of material elements were studied. Bone neoformation was observed in response to all materials. No sign of necrosis were found on the walls of the pre-existing cortical bone. No osteoclasts and no formation of fibrous tissue were evident. Sign of angiogenesis were present. EDX (element content, line profile and element mapping) showed the increase in Ca and P and decrease in C, S and N from the mature bone towards the mineralizing interface. Ca/P, Ca/N and P/N ratios showed differences in the degree of mineralization/maturation stage of bone. MTA Plus and ProRoot MTA exhibited close contact with the pre-existing bone and good bone-bonding with neoformed bone juxtaposed on the medullary side of the materials without interposed connective tissue or resorption lacunae or gaps. The materials showed a dense appearance with 100% of residual materials and no colonization by fluids and cells. No migration of Bi or Al material elements to the newly formed bone was found. Biodentine showed newly formed trabecular bone with marrow spaces and sparse traces of residual material (≈9%). The in vivo osteoinductive properties with dynamic biomineralization processes around these calcium silicate materials extruded

  19. Histologic Evaluation of Bone Healing Following Application of Anorganic Bovine Bone and β-tricalcium Phosphate in Rabbit Calvaria

    Directory of Open Access Journals (Sweden)

    AR. Rokn

    2012-01-01

    Full Text Available Objective: Both anorganic bovine bone (ABB and β-tricalcium phosphate (β- TCP are used in clinical practice as bone substitute materials, but there is limited data comparing these two materials in standardized defects.The aim of this study was to histologically evaluate the effectiveness of ABB and β-TCP in the healing of experimentally induced bone defects.Materials and Methods: Eighteen bone defects were created on the calvaria of six rabbits. In each animal, one defect was left untreated and the other two werefilled with ABB and β-TCP. After one month, histological sections were prepared.Type and vitality of newly formed bone, percentage of new bone formation and residual material, thickness of trabeculae, inflammation and foreign body reaction were assessed.Results: The newly formed osseous tissue was vital in all defects and consisted of woven and lamellar bone. Mean percentages of new bone formation were 30.83±14.29%, 16.83±11.07% and 14.00±8.17% in β-TCP, ABB and control groups, respectively and the mean percentages of residual biomaterial were 24.17±14.01% and 36.50±8.43% in β-TCP and ABB groups, respectively. However,the differences were not statistically significant (all ps>0.05. Inflammatoryinfiltration was statistically higher in β-TCP compared to the control group (p=0.025, but the difference was not significant between β-TCP and ABB groups (p=0.083. Trabeculation thickness and foreign body reaction were not statistically different between β-TCP and ABB groups.Conclusion: β-TCP and ABB were not different with regard to the quantity and quality of newly formed osseous tissue. However, inflammatory infiltration washigher in sites filled with β-TCP.

  20. No influence of simultaneous bone-substitute application on the success of immediately loaded dental implants: a retrospective cohort study.

    Science.gov (United States)

    Kopp, Sigmar; Behrend, Detlef; Kundt, Günther; Ottl, Peter; Frerich, Bernhard; Warkentin, Mareike

    2013-06-01

    To examine the influence of bone-substitute application during implantation on the success of immediately placed and loaded dental implants. A total of 147 consecutive patients (age, 16.5-80.4 years) were provided with 696 immediately loaded implants. The mean follow-up time was 34.1 months. Of these implants, 50.4% (n=351) were immediately placed into extraction sockets. A total of 119 implants were added by simultaneous bone-substitute application (NanoBone, Artoss GmbH, Rostock Germany), whereas the other implants were placed in healed bone. Univariate and multivariate analysis was performed using IBM SPSS V.20. The overall implant success rate was 96.1%. Implants with simultaneous bone replacement had a hazard ratio of 0.877 (p=0.837); 95% CI, 0.253-3.04). Factors found to be statistically significant modifiers of success on multivariate analysis (p<0.05) included type of superstructure (p<0.001), implant-abutment connection (p<0.001), membrane use (p=0.010), and jaw (p=0.026). None of the other factors investigated were significant modifiers. The present study demonstrates high success rates for immediately loaded implants and their superstructures independent of the simultaneous application of bone substitute. The declared aim of socket preservation, the prevention avoiding bone loss, is achieved in the immediate implant placement scenario under immediate-loading conditions.

  1. Profiling application potential for alkali treated sisal fiber ...

    African Journals Online (AJOL)

    ATHARVA

    Keywords: Ashby plot, Weibull analysis, sisal-fiber composite, alkali treatment. DOI: http://dx.doi.org/10.4314/ijest.v9i3.4. 1. Introduction. Presently, there is an ever-increasing demand for .... identify potential causal to degradation of the fiber structural integrity, and subsequently assign market application potential of the.

  2. Potential geothermal energy applications for Idaho Elks Rehabilitation Hospital

    Energy Technology Data Exchange (ETDEWEB)

    Austin, J.C.

    1981-11-01

    Several potential applications of geothermal energy for the Idaho Elks Rehabilitation Hospital are outlined. A brief background on the resource and distribution system, is provided; which hospital heating systems should be considered for potential geothermal retrofit is discussed; and technical and economic feasibility are addressed.

  3. Potential pitfalls of steatopygia on bone imaging using Tc99m MDP and role of SPECT

    International Nuclear Information System (INIS)

    Elgazzar, H; Elsaid, M; Omar, A; Al-Maskery, IB

    2004-01-01

    Body habbitus influence the quality of bone scintigraphy. Steatopygia (steato: fat, pygia: buttocks) may affect the quality of bone scan since it may lead to diagnostic pitfalls. Objective: The objective of this prospective study is to evaluate the effects of steatopygia on the appearance of the lumbar spine on bone scan and the role of SPECT in overcoming fat attenuation artifact if present. Method: Bone scintigraphy, including whole body bone scan, spot views and SPECT of the lumber spine, using a dual head gamma camera, were performed on thirty adult obese patients (13 males, 17 females) with an average weight of 90 kg. referred to the department for routine bone scan. Each patient was injected intravenously with 0.25 mCi/kg (9.25 Mbq of Tc-99m MDP, and their weight and height of each patient were recorded. Whole body scan was performed using 256 X 1024 matrix size and 8 min/meter speed. SPECT was performed using 128 X 128 matrix size, 20 second-32 projections and elliptical orbit around the lumbar spine. Spot views were acquired using 256X256 matrix size for 1000 Kcounts. Results: Twenty patients (67%) (6 males, 14 females) showed steatopygia with attenuation at the lower lumber vertebrae. Diminished uptake in the lower lumbar spine and edge effect artifacts were noted on planar images mimicking abnormalities. SPECT, especially in the sagittal axis, resolved these artifacts. Conclusion: Steatopygia should be considered in the interpretation of bone scans of obese patients to avoid diagnostic pitfalls. Adding SPECT of the lumber spine to the planar imaging improves the diagnostic accuracy in obese patients by overcoming the steatopygia effect seen on whole body and spot planar images. (authors)

  4. Potential game theory applications in radio resource allocation

    CERN Document Server

    Lã, Quang Duy; Soong, Boon-Hee

    2016-01-01

    This book offers a thorough examination of potential game theory and its applications in radio resource management for wireless communications systems and networking. The book addresses two major research goals: how to identify a given game as a potential game, and how to design the utility functions and the potential functions with certain special properties in order to formulate a potential game. After proposing a unifying mathematical framework for the identification of potential games, the text surveys existing applications of this technique within wireless communications and networking problems found in OFDMA 3G/4G/WiFi networks, as well as next-generation systems such as cognitive radios and dynamic spectrum access networks. Professionals interested in understanding the theoretical aspect of this specialized field will find Potential Game Theory a valuable resource, as will advanced-level engineering students. It paves the way for extensive and rigorous research exploration on a topic whose capacity for...

  5. Reduced cellularity of bone marrow in multiple sclerosis with decreased MSC expansion potential and premature ageing in vitro.

    Science.gov (United States)

    Redondo, Juliana; Sarkar, Pamela; Kemp, Kevin; Virgo, Paul F; Pawade, Joya; Norton, Aimie; Emery, David C; Guttridge, Martin G; Marks, David I; Wilkins, Alastair; Scolding, Neil J; Rice, Claire M

    2017-05-01

    Autologous bone-marrow-derived cells are currently employed in clinical studies of cell-based therapy in multiple sclerosis (MS) although the bone marrow microenvironment and marrow-derived cells isolated from patients with MS have not been extensively characterised. To examine the bone marrow microenvironment and assess the proliferative potential of multipotent mesenchymal stromal cells (MSCs) in progressive MS. Comparative phenotypic analysis of bone marrow and marrow-derived MSCs isolated from patients with progressive MS and control subjects was undertaken. In MS marrow, there was an interstitial infiltrate of inflammatory cells with lymphoid (predominantly T-cell) nodules although total cellularity was reduced. Controlling for age, MSCs isolated from patients with MS had reduced in vitro expansion potential as determined by population doubling time, colony-forming unit assay, and expression of β-galactosidase. MS MSCs expressed reduced levels of Stro-1 and displayed accelerated shortening of telomere terminal restriction fragments (TRF) in vitro. Our results are consistent with reduced proliferative capacity and ex vivo premature ageing of bone-marrow-derived cells, particularly MSCs, in MS. They have significant implication for MSC-based therapies for MS and suggest that accelerated cellular ageing and senescence may contribute to the pathophysiology of progressive MS. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Funding for this study was provided by the Medical Research Council, UK (grant no. MR/K004166/1). The ACTiMuS study is sup-ported by the Silverman Family Foundation, Multiple Sclerosis Trust, Rosetree’s Trust, Catholic Bishops of England and Wales and Friends of Frenchay and SIAMMS-II by the Sir Halley Stewart Trust. C.M.R., P.S., and K.K. received support from the Burden Neurological Institute.

  6. VSTM-v1, a potential myeloid differentiation antigen that is downregulated in bone marrow cells from myeloid leukemia patients

    OpenAIRE

    Xie, Min; Li, Ting; Li, Ning; Li, Jinlan; Yao, Qiumei; Han, Wenling; Ruan, Guorui

    2015-01-01

    Leukocyte differentiation antigens often represent important markers for the diagnosis, classification, prognosis, and therapeutic targeting of myeloid leukemia. Herein, we report a potential leukocyte differentiation antigen gene VSTM1 (V-set and transmembrane domain-containing 1) that was downregulated in bone marrow cells from leukemia patients and exhibited a higher degree of promoter methylation. The expression level of its predominant encoded product, VSTM1-v1, was positively correlated...

  7. Stromal cell-derived factor-1β potentiates bone morphogenetic protein-2-stimulated osteoinduction of genetically engineered bone marrow-derived mesenchymal stem cells in vitro.

    Science.gov (United States)

    Herberg, Samuel; Fulzele, Sadanand; Yang, Nianlan; Shi, Xingming; Hess, Matthew; Periyasamy-Thandavan, Sudharsan; Hamrick, Mark W; Isales, Carlos M; Hill, William D

    2013-01-01

    Skeletal injuries are among the most prevalent clinical problems and bone marrow-derived mesenchymal stem/stromal cells (BMSCs) have successfully been used for the treatment thereof. Stromal cell-derived factor-1 (SDF-1; CXCL12) is a member of the CXC chemokine family with multiple splice variants. The two most abundant variants, SDF-1α and SDF-1β, share identical amino acid sequences, except for four additional amino acids at the C-terminus of SDF-1β, which may mediate surface stabilization via glycosaminoglycans and protect SDF-1β from proteolytic cleavage, rendering it twice as potent as SDF-1α. Increasing evidence suggests that SDF-1 is involved in bone formation through regulation of recruitment, engraftment, proliferation, and differentiation of stem/progenitor cells. The underlying molecular mechanisms, however, have not yet been fully elucidated. In this study, we tested the hypothesis that SDF-1β can potentiate bone morphogenetic protein-2 (BMP-2)-stimulated osteogenic differentiation and chemotaxis of BMSCs in vitro. Utilizing retrovirus-mediated gene transfer to generate novel Tet-Off-SDF-1β BMSCs, we found that conditional SDF-1β expression is tightly regulated by doxycycline in a dose-dependent and temporal fashion, leading to significantly increased SDF-1β mRNA and protein levels. In addition, SDF-1β was found to enhance BMP-2-stimulated mineralization, mRNA and protein expression of key osteogenic markers, and regulate BMP-2 signal transduction via extracellular signal-regulated kinases 1/2 (Erk1/2) phosphorylation in genetically engineered BMSCs in vitro. We also showed that SDF-1β promotes the migratory response of CXC chemokine receptor 4 (CXCR4)-expressing BMSCs in vitro. Taken together, these data support that SDF-1β can play an important role in BMP-2-stimulated osteogenic differentiation of BMSCs and may exert its biological activity in both an autocrine and paracrine fashion.

  8. Locust bean gum: Exploring its potential for biopharmaceutical applications.

    Science.gov (United States)

    Dionísio, Marita; Grenha, Ana

    2012-07-01

    Polysaccharides have been finding, in the last decades, very interesting and useful applications in the biomedical and, specifically, in the biopharmaceutical field. Locust bean gum is a polysaccharide belonging to the group of galactomannans, being extracted from the seeds of the carob tree (Ceratonia siliqua). This polymer displays a number of appealing characteristics for biopharmaceutical applications, among which its high gelling capacity should be highlighted. In this review, we describe critical aspects of locust bean gum, contributing for its role in biopharmaceutical applications. Physicochemical properties, as well as strong and effective synergies with other biomaterials are described. The potential for in vivo biodegradation is explored and the specific biopharmaceutical applications are discussed.

  9. Local Application of Growth Hormone to Enhance Osseointegration in Osteoporotic Bones: A Morphometric and Densitometric Study.

    Science.gov (United States)

    Martin-Monge, Elena; Tresguerres, Isabel F; Clemente, Celia; Tresguerres, Jesús Af

    The aim of this study was to assess the effect of local application of growth hormone on osseointegration of dental implants inserted in osteoporotic bones. Twenty female New Zealand rabbits were used in this study. Ten were ovariectomized and fed a low-calcium diet for 6 weeks, and the others remained intact. A titanium implant was inserted into each tibia, in both groups. In half of the rabbits, 2 IU of growth hormone was placed into the ostectomy prior to the implant insertion. Two weeks after implant surgery, all animals were sacrificed. Tibiae were dissected from soft tissues, and included in methacrylate to be studied under light microscopy. Bone-to-implant contact (BIC) and bone mineral density (BMD) were measured by morphometric and densitometric analysis, respectively. Multifactorial analysis of variance (ANOVA) was used for statistical evaluation. P growth hormone was able to increase the BIC in the ovariectomized group, with statistically significant differences with respect to the control group (P growth hormone at the moment of titanium implant insertion in rabbit tibiae significantly enhanced the BIC around titanium implants 15 days after the implantation in this experimental osteoporotic animal model, without affecting the BMD.

  10. Development of gelatin/carboxymethyl chitosan/nano-hydroxyapatite composite 3D macroporous scaffold for bone tissue engineering applications.

    Science.gov (United States)

    Maji, Somnath; Agarwal, Tarun; Das, Joyjyoti; Maiti, Tapas Kumar

    2018-06-01

    The present study delineates a relatively simpler approach for fabrication of a macroporous three-dimensional scaffold for bone tissue engineering. The novelty of the work is to obtain a scaffold with macroporosity (interconnected networks) through a combined approach of high stirring induced foaming of the gelatin/carboxymethyl chitosan (CMC)/nano-hydroxyapatite (nHAp) matrix followed by freeze drying. The fabricated macroporous (SGC) scaffold had a greater pore size, higher porosity, higher water retention capacity, slow and sustained enzymatic degradation rate along with higher compressive strength compared to that of non-macroporous (NGC, prepared by conventional freeze drying methodology) scaffold. The biological studies revealed the increased percentage of viability, proliferation, and differentiation as well as higher mineralization of differentiated human Wharton's jelly MSC microtissue (wjhMSC-MT) on SGC as compared to NGC scaffold. RT-PCR also showed enhanced expression level of collagen type I, osteocalcin and Runx2 when seeded on SGC. μCT and histological analysis further revealed a penetration of cellular spheroid to a greater depth in SGC scaffold than NGC scaffold. Furthermore, the effect of cryopreservation on microtissue survival on the three-dimensional construct revealed significant higher viability upon revival in macroporous SGC scaffolds. These results together suggest that high stirring based macroporous scaffolds could have a potential application in bone tissue engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. MicroRNAs: Potential Biomarkers and Therapeutic Targets for Alveolar Bone Loss in Periodontal Disease

    Directory of Open Access Journals (Sweden)

    Tadayoshi Kagiya

    2016-08-01

    Full Text Available Periodontal disease is an inflammatory disease caused by bacterial infection of tooth-supporting structures, which results in the destruction of alveolar bone. Osteoclasts play a central role in bone destruction. Osteoclasts are tartrate-resistant acid phosphatase (TRAP-positive multinucleated giant cells derived from hematopoietic stem cells. Recently, we and other researchers revealed that microRNAs are involved in osteoclast differentiation. MicroRNAs are novel, single-stranded, non-coding, small (20–22 nucleotides RNAs that act in a sequence-specific manner to regulate gene expression at the post-transcriptional level through cleavage or translational repression of their target mRNAs. They regulate various biological activities such as cellular differentiation, apoptosis, cancer development, and inflammatory responses. In this review, the roles of microRNAs in osteoclast differentiation and function during alveolar bone destruction in periodontal disease are described.

  12. Clinical application of autogenous partially demineralized dentin matrix prepared immediately after extraction for alveolar bone regeneration in implant dentistry: a pilot study.

    Science.gov (United States)

    Minamizato, T; Koga, T; I, Takashi; Nakatani, Y; Umebayashi, M; Sumita, Y; Ikeda, T; Asahina, I

    2018-01-01

    The aim of this study was to examine the efficacy and safety of autogenous partially demineralized dentin matrix (APDDM) prepared onsite, for clinical application in bone regeneration procedures related to implant dentistry, including socket preservation, alveolar ridge augmentation, and maxillary sinus floor augmentation. In this study, 16 patients underwent dental implant placement using APDDM transplantation. There were no systemic or local complications (including surgical site infection) in any of the cases, and oral rehabilitation using dental implants was successful in all cases for at least 2 years after attachment of the suprastructure. This report describes the clinical application of APDDM prepared immediately after tooth extraction to bone augmentation, taking advantage of the relatively short preparation time due to partial demineralization. APDDM, as introduced in this study, is an efficient, safe, and reasonable bone substitute. Consequently, this material has the potential to become one of the options as a bone substitute in implant dentistry. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. Novel modeling of combinatorial miRNA targeting identifies SNP with potential role in bone density.

    Directory of Open Access Journals (Sweden)

    Claudia Coronnello

    Full Text Available MicroRNAs (miRNAs are post-transcriptional regulators that bind to their target mRNAs through base complementarity. Predicting miRNA targets is a challenging task and various studies showed that existing algorithms suffer from high number of false predictions and low to moderate overlap in their predictions. Until recently, very few algorithms considered the dynamic nature of the interactions, including the effect of less specific interactions, the miRNA expression level, and the effect of combinatorial miRNA binding. Addressing these issues can result in a more accurate miRNA:mRNA modeling with many applications, including efficient miRNA-related SNP evaluation. We present a novel thermodynamic model based on the Fermi-Dirac equation that incorporates miRNA expression in the prediction of target occupancy and we show that it improves the performance of two popular single miRNA target finders. Modeling combinatorial miRNA targeting is a natural extension of this model. Two other algorithms show improved prediction efficiency when combinatorial binding models were considered. ComiR (Combinatorial miRNA targeting, a novel algorithm we developed, incorporates the improved predictions of the four target finders into a single probabilistic score using ensemble learning. Combining target scores of multiple miRNAs using ComiR improves predictions over the naïve method for target combination. ComiR scoring scheme can be used for identification of SNPs affecting miRNA binding. As proof of principle, ComiR identified rs17737058 as disruptive to the miR-488-5p:NCOA1 interaction, which we confirmed in vitro. We also found rs17737058 to be significantly associated with decreased bone mineral density (BMD in two independent cohorts indicating that the miR-488-5p/NCOA1 regulatory axis is likely critical in maintaining BMD in women. With increasing availability of comprehensive high-throughput datasets from patients ComiR is expected to become an essential

  14. Sequential Treatment with SDF-1 and BMP-2 Potentiates Bone Formation in Calvarial Defects.

    Science.gov (United States)

    Hwang, Hee-Don; Lee, Jung-Tae; Koh, Jeong-Tae; Jung, Hong-Moon; Lee, Heon-Jin; Kwon, Tae-Geon

    2015-07-01

    Stromal cell-derived factor-1 (SDF-1) protein and its receptor, CXCR-4, play an important role in tissue repair and regeneration in various organs, including the bone. SDF-1 is indispensable for bone morphogenetic protein-2 (BMP-2)-induced osteogenic differentiation. However, SDF-1 is not needed after the osteogenic induction has been activated. Since the precise condition for the additive effects of combined DF-1 and BMP-2 in bone healing had not been fully investigated, we aimed to determine the optimal conditions for SDF-1- and BMP-2-mediated bone regeneration. We examined the in vitro osteoblastic differentiation and cell migration after sequential treatments with SDF-1 and BMP-2. Based on the in vitro additive effects of SDF-1 and BMP-2, the critical size defects of mice calvaria were treated with these cytokines in various sequences. Phosphate buffered saline (PBS)-, SDF-1-, or BMP-2-soaked collagen scaffolds were implanted into the calvarial defects (n=36). Periodic percutaneous injections of PBS or the cytokine SDF-1 and BMP-2 into the implanted scaffolds were performed on days 3 and 6, postoperatively. Six experimental groups were used according to the types and sequences of the cytokine treatments. After 28 days, the mice were euthanized and bone formation was evaluated with microcomputed tomography and histology. The molecular mechanism of the additive effect of SDF-1 and BMP-2 was evaluated by analyzing intracellular signal transduction through Smad and Erk phosphorylation. The in vitro experiments revealed that, among all the treatments, the treatment with BMP-2 after SDF-1 showed the strongest osteoblastic differentiation and enhanced cell migration. Similarly, in the animal model, the treatment with SDF-1 followed by BMP-2 treatment showed the highest degree of new bone regeneration than any other groups, including the one with continuous BMP-2 treatment. This new bone formation can be partially explained by the activation of Smad and Erk pathways

  15. From the printer: Potential of three-dimensional printing for orthopaedic applications

    Directory of Open Access Journals (Sweden)

    Sze-Wing Mok

    2016-07-01

    Full Text Available Three-dimensional (3D printers can create complex structures based on digital models. The combination of medical diagnostic imaging with 3D printing has great potential in day-to-day clinics for patient-specific solutions and applications. In the musculoskeletal system, 3D printing is used to create custom-made implants, patient-specific instrumentation, and to regenerate tissues, in particular bone and cartilage. The major limiting factors for bioprinting include the lack of printing techniques with optimal printing resolution and materials with ideal mechanical strengths while maintaining cellular functionality. Before “tissues from the printer” can be widely applied, further research and development on improving and optimising printing techniques and biomaterials, and knowledge on the development of printed constructs into living tissues, is essential for future clinical application of this technology.

  16. Clinical Applications of S53P4 Bioactive Glass in Bone Healing and Osteomyelitic Treatment: A Literature Review

    Directory of Open Access Journals (Sweden)

    N. A. P. van Gestel

    2015-01-01

    Full Text Available Nowadays, S53P4 bioactive glass is indicated as a bone graft substitute in various clinical applications. This review provides an overview of the current published clinical results on indications such as craniofacial procedures, grafting of benign bone tumour defects, instrumental spondylodesis, and the treatment of osteomyelitis. Given the reported results that are based on examinations, such as clinical examinations by the surgeons, radiographs, CT, and MRI images, S53P4 bioactive glass may be beneficial in the various reported applications. Especially in craniofacial reconstructions like mastoid obliteration and orbital floor reconstructions, in grafting bone tumour defects, and in the treatment of osteomyelitis very promising results are obtained. Randomized clinical trials need to be performed in order to determine whether bioactive glass would be able to replace the current golden standard of autologous bone usage or with the use of antibiotic containing PMMA beads (in the case of osteomyelitis.

  17. Clinical Application of Mesenchymal Stem Cells and Novel Supportive Therapies for Oral Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Miguel Padial-Molina

    2015-01-01

    Full Text Available Bone regeneration is often needed prior to dental implant treatment due to the lack of adequate quantity and quality of the bone after infectious diseases, trauma, tumor, or congenital conditions. In these situations, cell transplantation technologies may help to overcome the limitations of autografts, xenografts, allografts, and alloplastic materials. A database search was conducted to include human clinical trials (randomized or controlled and case reports/series describing the clinical use of mesenchymal stem cells (MSCs in the oral cavity for bone regeneration only specifically excluding periodontal regeneration. Additionally, novel advances in related technologies are also described. 190 records were identified. 51 articles were selected for full-text assessment, and only 28 met the inclusion criteria: 9 case series, 10 case reports, and 9 randomized controlled clinical trials. Collectively, they evaluate the use of MSCs in a total of 290 patients in 342 interventions. The current published literature is very diverse in methodology and measurement of outcomes. Moreover, the clinical significance is limited. Therefore, the use of these techniques should be further studied in more challenging clinical scenarios with well-designed and standardized RCTs, potentially in combination with new scaffolding techniques and bioactive molecules to improve the final outcomes.

  18. Clinical Application of Mesenchymal Stem Cells and Novel Supportive Therapies for Oral Bone Regeneration

    Science.gov (United States)

    O'Valle, Francisco; Lanis, Alejandro; Dohan Ehrenfest, David M.; Wang, Hom-Lay; Galindo-Moreno, Pablo

    2015-01-01

    Bone regeneration is often needed prior to dental implant treatment due to the lack of adequate quantity and quality of the bone after infectious diseases, trauma, tumor, or congenital conditions. In these situations, cell transplantation technologies may help to overcome the limitations of autografts, xenografts, allografts, and alloplastic materials. A database search was conducted to include human clinical trials (randomized or controlled) and case reports/series describing the clinical use of mesenchymal stem cells (MSCs) in the oral cavity for bone regeneration only specifically excluding periodontal regeneration. Additionally, novel advances in related technologies are also described. 190 records were identified. 51 articles were selected for full-text assessment, and only 28 met the inclusion criteria: 9 case series, 10 case reports, and 9 randomized controlled clinical trials. Collectively, they evaluate the use of MSCs in a total of 290 patients in 342 interventions. The current published literature is very diverse in methodology and measurement of outcomes. Moreover, the clinical significance is limited. Therefore, the use of these techniques should be further studied in more challenging clinical scenarios with well-designed and standardized RCTs, potentially in combination with new scaffolding techniques and bioactive molecules to improve the final outcomes. PMID:26064899

  19. Insertion Torques of Self-Drilling Mini-Implants in Simulated Mandibular Bone: Assessment of Potential for Implant Fracture.

    Science.gov (United States)

    Hosein, Yara K; Smith, Angie; Dunning, Cynthia E; Tassi, Ali

    2016-01-01

    Fracture of orthodontic mini-implants during insertion is a limiting factor for their clinical success. The purpose of this study was to determine the fracture potential of commonly used self-drilling orthodontic mini-implants when placed into simulated thick, dense mandibular bone. Six mini-implant systems were assessed for the potential for fracture (Aarhus, Medicon; Dual-Top, Jeil Medical; OrthoEasy, Forestadent; tomas-pin, Dentaurum; Unitek, 3M; and VectorTAS, Ormco). First, mini-implants were inserted manually, without predrilling, into bone substitutes (Sawbones) with a 3-mm-thick, dense (1.64 g/cm(3)) cortical layer. A custom-made insertion device was used for placement of mini-implants. A sixaxis force/torque transducer was secured at the base of the bone blocks to measure the maximum torque experienced during insertion. Measured insertion torques were compared with previously reported fracture torques, yielding a torque ratio (insertion torque as a percentage of fracture torque), which was used as an indicator of the potential for mini-implant fracture. Mini-implants that experienced torque ratios ≥ 75% upon insertion underwent further testing, following the manufacturer's recommendations for predrilling in thick, dense bone conditions. Significant differences in torque ratios were found among all mini-implants, except between OrthoEasy and Dual-Top, and OrthoEasy and VectorTAS. Overall, Aarhus had the highest torque ratio (91% ± 3%), with Unitek showing the lowest ratio (37% ± 3%). Aarhus and tomas-pin mini-implants displayed torque ratios ≥ 75% and experienced fracture upon insertion. When the manufacturer's specific predrilling recommendations were followed, no changes in torque ratio were found for Aarhus and tomas-pin. However, while Aarhus continued to fracture upon insertion, all tomas-pin mini-implants were inserted fully without fracture following predrilling. These findings support the safe use of Unitek, VectorTAS, Dual-Top, and Ortho

  20. Neural differentiation potential of human bone marrow-derived mesenchymal stromal cells: misleading marker gene expression

    Directory of Open Access Journals (Sweden)

    Montzka Katrin

    2009-03-01

    Full Text Available Abstract Background In contrast to pluripotent embryonic stem cells, adult stem cells have been considered to be multipotent, being somewhat more restricted in their differentiation capacity and only giving rise to cell types related to their tissue of origin. Several studies, however, have reported that bone marrow-derived mesenchymal stromal cells (MSCs are capable of transdifferentiating to neural cell types, effectively crossing normal lineage restriction boundaries. Such reports have been based on the detection of neural-related proteins by the differentiated MSCs. In order to assess the potential of human adult MSCs to undergo true differentiation to a neural lineage and to determine the degree of homogeneity between donor samples, we have used RT-PCR and immunocytochemistry to investigate the basal expression of a range of neural related mRNAs and proteins in populations of non-differentiated MSCs obtained from 4 donors. Results The expression analysis revealed that several of the commonly used marker genes from other studies like nestin, Enolase2 and microtubule associated protein 1b (MAP1b are already expressed by undifferentiated human MSCs. Furthermore, mRNA for some of the neural-related transcription factors, e.g. Engrailed-1 and Nurr1 were also strongly expressed. However, several other neural-related mRNAs (e.g. DRD2, enolase2, NFL and MBP could be identified, but not in all donor samples. Similarly, synaptic vesicle-related mRNA, STX1A could only be detected in 2 of the 4 undifferentiated donor hMSC samples. More significantly, each donor sample revealed a unique expression pattern, demonstrating a significant variation of marker expression. Conclusion The present study highlights the existence of an inter-donor variability of expression of neural-related markers in human MSC samples that has not previously been described. This donor-related heterogeneity might influence the reproducibility of transdifferentiation protocols as

  1. Hydroxyapatite from fish scale for potential use as bone scaffold or regenerative material

    Energy Technology Data Exchange (ETDEWEB)

    Pon-On, Weeraphat, E-mail: fsciwpp@ku.ac.th [Department of Physics, Faculty of Science, Kasetsart University, Bangkok (Thailand); Suntornsaratoon, Panan [Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok (Thailand); Charoenphandhu, Narattaphol [Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok (Thailand); Department of Physiology, Faculty of Science, Mahidol University, Bangkok (Thailand); Thongbunchoo, Jirawan [Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok (Thailand); Krishnamra, Nateetip [Center of Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok (Thailand); Department of Physiology, Faculty of Science, Mahidol University, Bangkok (Thailand); Tang, I. Ming [Department of Materials Science, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand)

    2016-05-01

    The present paper studies the physico-chemical, bioactivity and biological properties of hydroxyapatite (HA) which is derived from fish scale (FS) (FSHA) and compares them with those of synthesized HA (sHA) obtained by co-precipitation from chemical solution as a standard. The analysis shows that the FSHA is composed of flat-plate nanocrystal with a narrow width size of about 15–20 nm and having a range of 100 nm in length and that the calcium phosphate ratio (Ca/P) is 2.01 (Ca-rich CaP). Whereas, synthesized HA consists of sub-micron HA particle having a Ca/P ratio of 1.65. Bioactivity test shows that the FSHA forms more new apatite than does the sHA after being incubated in simulated body fluid (SBF) for 7 days. Moreover, the biocompatibility study shows a higher osteoblast like cell adhesion on the FSHA surface than on the sHA substrate after 3 days of culturing. Our results also show the shape of the osteoblast cells on the FSHA changes from being a rounded shape to being a flattened shape reflecting its spreading behavior on this surface. MTT assay and ALP analysis show significant increases in the proliferation and activity of osteoblasts over the FSHA scaffold after 5 days of culturing as compared to those covering the sHA substrates. These results confirm that the bio-materials derived from fish scale (FSHA) are biologically better than the chemically synthesized HA and have the potential for use as a bone scaffold or as regenerative materials. - Highlights: • Preparation of hydroxyapatite (HA) which is derived from fish scale (FS) (FSHA) and their bioactivities • The FSHA is composed of flat-plate nanocrystal with a narrow size of 15–20 nm. • Bioactivity test shows that the FSHA forms more new apatite than does the sHA after being incubated SBF. • In vitro cell availability tests show a higher cell adhesion on the FSHA surface.

  2. Calcium aluminates potential for endodontics and orthopedics applications

    International Nuclear Information System (INIS)

    Santos, G.L. dos; Andrade, T.L.; Oliveira, I.R.; Pandolfelli, V.C.

    2011-01-01

    The mostly used material in the areas of endodontics (MTA, mineral trioxide aggregate) and bone reconstruction (PMMA, polymethyl methacrylate) present some limiting properties requiring thus changes in their compositions as well as the development of alternative materials. In this context, a novel biomaterial-based calcium aluminate cement (CAC) has been studied in order to keep the positive properties and clinical applications of MTA and PMMA, overcoming some their disadvantages. Recent studies involving the use of CAC are based on commercial products consisting of a mixture of phases. Improvements can be attained by searching the synthesis routes of CAC aiming the proper balance between the phases and the control of impurities that may impair its performance in applications in the areas of health. By the optimization of the CAC phases production, this article aims to present their characterization based on hydration temperature; working time and setting time; pH, ions solubilization and dissolution in contact with water and different solutions of simulated body fluid. The results indicated the CA phase as the most suitable for application in the areas of health. (author)

  3. Concise reviews: Characteristics and potential applications of human dental tissue-derived mesenchymal stem cells.

    Science.gov (United States)

    Liu, Junjun; Yu, Fang; Sun, Yao; Jiang, Beizhan; Zhang, Wenjun; Yang, Jianhua; Xu, Guo-Tong; Liang, Aibin; Liu, Shangfeng

    2015-03-01

    Recently, numerous types of human dental tissue-derived mesenchymal stem cells (MSCs) have been isolated and characterized, including dental pulp stem cells, stem cells from exfoliated deciduous teeth, periodontal ligament stem cells, dental follicle progenitor cells, alveolar bone-derived MSCs, stem cells from apical papilla, tooth germ progenitor cells, and gingival MSCs. All these MSC-like cells exhibit self-renewal, multilineage differentiation potential, and immunomodulatory properties. Several studies have demonstrated the potential advantages of dental stem cell-based approaches for regenerative treatments and immunotherapies. This review outlines the properties of various dental MSC-like populations and the progress toward their use in regenerative therapy. Several dental stem cell banks worldwide are also introduced, with a view toward future clinical application. © 2014 AlphaMed Press.

  4. Selection of phosphorus solubilizing bacteria with biocontrol potential for growth in phosphorus rich animal bone charcoal

    NARCIS (Netherlands)

    Postma, J.; Nijhuis, E.H.; Sommeus, E.

    2010-01-01

    Bacteria with the ability to solubilize phosphorus (P) and to improve plant health were selected and tested for growth and survival in P-rich animal bone charcoal (ABC). ABC is suggested to be suitable as a carrier for biocontrol agents, offering them a protected niche as well as delivering

  5. Bone ingrowth potential of electron beam and selective laser melting produced trabecular-like implant surfaces with and without a biomimetic coating

    NARCIS (Netherlands)

    Biemond, J.E.; Hannink, G.; Verdonschot, Nicolaas Jacobus Joseph; Buma, P.

    2013-01-01

    The bone ingrowth potential of trabecular-like implant surfaces produced by either selective laser melting (SLM) or electron beam melting (EBM), with or without a biomimetic calciumphosphate coating, was examined in goats. For histological analysis and histomorphometry of bone ingrowth depth and

  6. [The potential of cone beam computed tomography of the temporal bones in the patients presenting with otosclerosis].

    Science.gov (United States)

    Karpishchenko, S A; Zubareva, A A; Filimonov, V N; Shavgulidze, M A; Azovtseva, E A

    The objective of the present study was to analyze the potential of cone beam computed tomography of the temporal bones in the patients presenting with otosclerosis for the detection of surgically significant specific structural features of the labyrinth wall of the tympanic cavity. More than 400 tomograms of the temporal bones were obtained with the use of a cone beam tomographwere available for the investigation during the period from 2012 till 2016. The study was carried out in several steps, viz. the search for the optimal (for the given instrument) position of the patient, the experimental stage, the retrospective analysis of the tomograms and the comparison of the temporal bones of different types (pneumatic, mixed, and sclerotic) in individual patients, the comparison of the results of cone beam computed tomography (CBCT) with the intraoperative observations, and the modification of the algorithm for the analysis of temporal bone cone beam tomograms. The study included a total of 16 patients (15 women at the age from 32 to 56 years and one managed 58 years) presenting with the clinical diagnosis of otosclerosis. The results of the study were used to elaborate the algorithm for the analysis of cone beam tomograms of the temporal bones to be performed inthe stage by stage manner including the qualitative analysis of tomograms, evaluation of their quantitative parameters and additional characteristics to be taken into consideration when planning the surgical interventions on the labyrinth wall and the tympanic cavity as a preparation for the stapedoplastic treatment. The results of CBCT obtained in the present study were compared with the surgical observations. The diagnostic sensitivity and specificity of the method were estimated to be 100% and 83% respectively. It is concluded that cone beam computed tomography can be employed as a component of the diagnostic algorithm prior to the planning of surgical interventions onthe medial wall of the tympanic cavity

  7. Recent progress in the differentiation of bone marrow derived ...

    African Journals Online (AJOL)

    ONOS

    2010-08-09

    Aug 9, 2010 ... Bone marrow mesenchymal stem cells (BMMSCs) are one of the cells found in bone marrow stromal. A large number of ..... Bone marrow stromal cell: Nature, Biology, and potential application. Stem cell,. 19(3): 180-192. Cao F, Sun DD, Li CX, Narsinh K, Zhao L, Li X Feng XY, Zhang J,. Duan YY, Wang J, ...

  8. Bacteriophages-potential for application in wastewater treatment processes

    International Nuclear Information System (INIS)

    Withey, S.; Cartmell, E.; Avery, L.M.; Stephenson, T.

    2005-01-01

    Bacteriophages are viruses that infect and lyse bacteria. Interest in the ability of phages to control bacterial populations has extended from medical applications into the fields of agriculture, aquaculture and the food industry. Here, the potential application of phage techniques in wastewater treatment systems to improve effluent and sludge emissions into the environment is discussed. Phage-mediated bacterial mortality has the potential to influence treatment performance by controlling the abundance of key functional groups. Phage treatments have the potential to control environmental wastewater process problems such as: foaming in activated sludge plants; sludge dewaterability and digestibility; pathogenic bacteria; and to reduce competition between nuisance bacteria and functionally important microbial populations. Successful application of phage therapy to wastewater treatment does though require a fuller understanding of wastewater microbial community dynamics and interactions. Strategies to counter host specificity and host cell resistance must also be developed, as should safety considerations regarding pathogen emergence through transduction

  9. Bone healing of critical size defects of the rat femur after the application of bone marrow aspirate and two different rh-BMP7 concentrations.

    Science.gov (United States)

    Högel, F; Hoffmann, S; Hungerer, S; Fleischacker, E; Ullamann, T; Betz, O B; Augat, P

    2015-10-01

    It is known that the application of growth factors can enhance fracture healing in defect fractures. The role of bone marrow aspirate (BMA) in combination with BMP-7 and the dosage of rh BMP-7 are still under discussion. Our hypothesis was that the combination of rh-BMP-7 with BMA can heal bone defects more effectively than rh-BMP-7 alone. Twenty-eight rats obtained a 5 mm critical size defect in the diaphysis of the right femur which was stabilized by a plate. Rh-BMP-7 was applied at 10 and 200 µg either with collagen or together with collagen and BMA. Collagen only and collagen with BMA served as control groups. Blood flow was assessed by laser Doppler flowmetry in regular time intervals until euthanasia. Callus formation and bone density were measured by micro-computed tomography and biomechanical stability was evaluated by torsional testing at 4 weeks, postoperatively. Blood flow increased at the operated side after surgery until the second postoperative week independent of treatment. Animals treated with high dose BMP-7 showed significantly (p = 0.001) increased mechanical stiffness independent of BMA treatment. Failure loads were lowest for the two control groups (p = 0.001). The reduction of the BMP-7 dose led to less callus tissue and lower biomechanical stability. BMA did not show significant influence on bone healing. The combination of an rhBMP-7 dose that would be equivalent to a dose used clinically in humans with bone marrow aspirate does not heal a critical bone defect more effectively than the same rhBMP-7 dose alone.

  10. Path Analysis Identifies Receptor Activator of Nuclear Factor-κB Ligand, Osteoprotegerin, and Sclerostin as Potential Mediators of the Tophus-bone Erosion Relationship in Gout.

    Science.gov (United States)

    Chhana, Ashika; Aati, Opetaia; Gamble, Gregory D; Callon, Karen E; Doyle, Anthony J; Roger, Mark; McQueen, Fiona M; Horne, Anne; Reid, Ian R; Cornish, Jillian; Dalbeth, Nicola

    2016-02-01

    To determine the relationship between tophus, erosion and bone remodeling factors in gout. Computed tomography bone erosion and circulating bone factors were measured in adults with tophaceous gout. Multiple regression modeling and path analysis were used to determine predictors of erosion. Tophus number, Māori or Pacific ethnicity, creatinine, receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), and sclerostin were independently associated with erosion. Path analysis showed a direct effect of tophus number on erosion, partially mediated through OPG, RANKL, and sclerostin. Tophus number is strongly associated with bone erosion in gout. Circulating RANKL, OPG, and sclerostin are potential mediators of tophus-related erosion.

  11. Bone-seeking therapeutic radiopharmaceuticals

    Directory of Open Access Journals (Sweden)

    Srivastava Suresh C.

    2002-01-01

    Full Text Available Bone-seeking therapeutic radiopharmaceuticals are utilized on the basis of the radionuclide?s particulate emissions (primarily low to intermediate beta emission. The requirements therefore are different from those of bone imaging agents that consist mainly of short-lived single photon emitters. Lately, the therapeutic bone seeking radiopharmaceuticals have attained increasing importance due to their potential role in alleviating pain from osseous metastases in cancer patients, for the treatment of joint pain resulting from inflamed synovium (radiosynoviorthesis, or radiosynovectomy, or from various other forms of arthritic disease. There is, however, a paucity of published data on the bio-pharmacokinetics of these agents when used following intravenous administration for bone pain palliation. This paper will briefly review and summarize the presently available chemical and biopharmacokinetic information on the various clinically approved as well as experimental bone-localizing therapeutic radiopharmaceuticals, and make projections on their clinical application for the treatment of primary/metastatic cancer in bone.

  12. Current trends in mesenchymal stem cell application in bone augmentation: a review of the literature.

    Science.gov (United States)

    Khojasteh, Arash; Behnia, Hossein; Dashti, Seyedeh Ghazaleh; Stevens, Mark

    2012-04-01

    The literature regarding mesenchymal stem cell (MSC)-based bone reconstruction techniques are sparse and no comprehensive review of current methods has been performed. The aim of this article was to provide a discussion of clinical and experimental reports of MSC application in the reconstruction of bony defects in live models. This search was executed using the PubMed database with various combinations of related keywords. Currently published English-language studies that had applied MSCs as a part of their treatment protocol for reconstruction of bony defects in rat, rabbit, dog, and human models were reviewed. The included studies had reported substantiation that the applied cells were of MSC origin as a part of the study design. Publications inclusive to February 1, 2010 were evaluated. Of review of 187 found abstracts and full texts, 25 articles met the inclusion criteria. Based on this review, tremendous differences exist among investigators for the application of MSCs in bone augmentation procedures. These differences include not only species uniqueness but also a plethora of other variances, such as stem cell source, defect sites and sizes, carriers and constructs, use of additional growth factors, measured parameters, and methods of data collection. Because of the multitude of protocols, range of parameters, and data in the current English-language literature, this review did not reach any significant conclusion as to the "most predictable" model in stem cell reconstruction. However, it does "shed light" on the need for additional collaborated studies using similar homogenous designs and data analysis in advancing the science of bone reconstruction using MSCs. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Characterisation of a new bioadhesive system based on polysaccharides with the potential to be used as bone glue.

    Science.gov (United States)

    Hoffmann, Bettina; Volkmer, Elias; Kokott, Andreas; Augat, Peter; Ohnmacht, Michael; Sedlmayr, Nicole; Schieker, Matthias; Claes, Lutz; Mutschler, Wolf; Ziegler, Günter

    2009-10-01

    Although gluing bone is in theory a very attractive alternative to classical fracture treatment, this method is not yet clinically established due to the lack of an adhesive which would meet all the necessary requirements. We therefore developed a novel two-component bioadhesive system with the potential to be used as a bone adhesive based on biocompatible and degradable biopolymers (chitosan, oxidised dextran or starch). After mixing in water, the two components covalently cross-link by forming a Schiff's base. By the same mechanism, the glue binds to any other exposed amino group such as for example those exposed in fractured bone, even in the presence of water. Modified chitosan was synthesised from commercially available chitosan by deacetylation and was then reduced in molecular weight by heating in acid. The amount of free amino groups was analysed by IR. The molecular weight was determined by viscosimetry. Starch or dextran were oxidised with periodic acid to generate aldehyde groups, which were quantified by titration. l-Dopa was conjugated to oxidised dextran or starch in analogy to the gluing mechanism of mussels. Biomechanical studies revealed that the new glue is superior to fibrin glue, but has less adhesive strength than cyanoacrylates. In vitro cell testing demonstrated excellent biocompatibility, rendering this glue a potential candidate for clinical use.

  14. Revisiting bone targeting potential of novel hydroxyapatite based surface modified PLGA nanoparticles of risedronate: Pharmacokinetic and biochemical assessment.

    Science.gov (United States)

    Rawat, Purnima; Ahmad, Iqbal; Thomas, Shindu C; Pandey, Shweta; Vohora, Divya; Gupta, Sarika; Ahmad, Farhan Jalees; Talegaonkar, Sushama

    2016-06-15

    Hydroxyapatite based biodegradable mPEG-PLGA nanoparticles of risedronate (mPEG-PLGA-RIS-HA) were prepared by water miscible dialysis method for synergistic treatment of osteoporosis. The bone targeting potential of prepared nanoparticles was evaluated by performing the cell viability study and protein estimation in pre-osteoblast cell line (MC3T3E1). Biochemical and in-vivo pharmacokinetic studies on osteoporotic rat model treated with different formulations were performed. Under the biochemical study ALP, TRAP, HxP and Calcium levels were determined. Osteoporotic model treated with prepared nanoparticles indicated significant effect on bone. Pharmacokinetic studies revealed 6-fold and 4-fold increase in the relative bioavailability after intravenous and oral administration of nanoparticles respectively as compared to marketed formulation confirming better effective drug transport. Biochemical investigations also showed a significant change in biomarker level which ultimately lead to bone formation/resorption. A stability analysis has also been carried out according to ICH guidelines (Q1AR2) and shelf life was found to be 1year and 4 months for the prepared formulation. Thus the results of present studies indicated that mPEG-PLGA-RIS-HA NPs has a great potential for sustained delivery of RIS for the treatment and prevention of osteoporosis and to minimize the adverse effects of RIS typically induced by its oral administration. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. The effect of combined application of TGFbeta-1, BMP-2, and COLLOSS E on the development of bone marrow derived osteoblast-like cells in vitro.

    NARCIS (Netherlands)

    Zande, M. van der; Walboomers, X.F.; Briest, A.; Springer, M.; Alava, J.I.; Jansen, J.A.

    2008-01-01

    This study investigated the combined application of Transforming Growth Factor beta-1 (TGFbeta-1) and Bone Morphogenetic Protein-2 (BMP-2) to stimulate osteogenic expression in vitro. TGFbeta-1 and BMP-2 fulfill specific roles in the formation of new bone. COLLOSS E, a bone-derived collagen product

  16. Telomerase expression extends the proliferative life-span and maintains the osteogenic potential of human bone marrow stromal cells

    DEFF Research Database (Denmark)

    Simonsen, Janne Lytoft; Rosada, Cecilia; Serakinci, Nedime

    2002-01-01

    . The transduced cells have now undergone more than 260 population doublings (PD) and continue to proliferate, whereas control cells underwent senescence-associated proliferation arrest after 26 PD. The cells maintained production of osteoblastic markers and differentiation potential during continuous subculturing......, did not form tumors, and had a normal karyotype. When implanted subcutaneously in immunodeficient mice, the transduced cells formed more bone than did normal cells. These results suggest that ectopic expression of telomerase in hMSCs prevents senescence-associated impairment of osteoblast functions.......Human bone marrow stromal cells (hMSCs) were stably transduced by a retroviral vector containing the gene for the catalytic subunit of human telomerase (hTERT). Transduced cells (hMSC-TERTs) had telomerase activity, and the mean telomere length was increased as compared with that of control cells...

  17. [Applications of myo-periosteal fibular bone bridging for traumatic transtibial amputation].

    Science.gov (United States)

    Song, Dengxin; Zhang, Qianfa; Zhu, Cheng; He, Xiaowen; Liao, Xiaohui; Yi, Chengla

    2013-11-01

    To compare the effectiveness between the myo-periosteal fibular bone bridging and traditional transtibial amputation in the treatment of amputation below knee so as to provide theoretical basis for choosing transtibial amputation in clinical application. Between November 2001 and November 2011, 38 patients with mangled lower extremity were treated by transtibial amputation. Among 38 patients, 17 (group A) underwent myo-periosteal fibular bone bridging (the operation techniques of an attached peroneal muscle myo-periosteal fibular strut bridge between the end of the tibia and fibula below knee amputation), and other 21 (group B) underwent traditional transtibial amputation. There was no significant difference in age, gender, injury cause, amputation cause, side, and disease duration between 2 groups (P > 0.05). The quality of life (QOL) was analyzed using 36-item short form health survey (SF-36), and prosthesis satisfaction by Trinity amputation and prosthesis experience scale (TAPES). Healing of incision by first intention was obtained in all patients of 2 groups; no necrosis, infection, or poor stumps was observed. The mean follow-up time was 22 months (range, 14-30 months) in group A, and 26 months (range, 15-30 months) in group B. The patients achieved good healing of bone bridging, no bone nonunion occurred. The healing time was (5.1 +/- 1.1) months in group A and (3.3 +/- 0.6) months in group B, showing significant difference between 2 groups (t=9.82, P=-0.00). Spur occurred at the distal fibula in an 11-year-old boy of group B after 2 years of operation, which blocked use of prosthesis; prosthesis was well used in the other patients. After 12 months of operation, SF-36 score was 55.84 +/- 14.01 in group A and 49.93 +/- 12.78 in group B, showing significant difference (P 0.05). TAPES score was 12.12 +/- 2.23 in group A and 10.10 +/- 2.00 in group B, showing significant difference (t=2.891, P=0.006). It is a very effective method to treat traumatic amputation

  18. Laser wakefield accelerator based light sources: potential applications and requirements

    Energy Technology Data Exchange (ETDEWEB)

    Albert, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). NIF and Photon Sciences; Thomas, A. G. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Nuclear Engineering and Radiological Sciences; Mangles, S. P.D. [Imperial College, London (United Kingdom). Blackett Lab.; Banerjee, S. [Univ. of Nebraska, Lincoln, NE (United States); Corde, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Flacco, A. [ENSTA, CNRS, Ecole Polytechnique, Palaiseau (France); Litos, M. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Neely, D. [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL). Central Laser Facility; Viera, J. [Univ. of Lisbon (Portugal). GoLP-Inst. de Plasmas e Fusao Nuclear-Lab. Associado; Najmudin, Z. [Imperial College, London (United Kingdom). Blackett Lab.; Bingham, R. [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL). Central Laser Facility; Joshi, C. [Univ. of California, Los Angeles, CA (United States). Dept. of Electrical Engineering; Katsouleas, T. [Duke Univ., Durham, NC (United States). Platt School of Engineering

    2015-01-15

    In this article we review the prospects of laser wakefield accelerators as next generation light sources for applications. This work arose as a result of discussions held at the 2013 Laser Plasma Accelerators Workshop. X-ray phase contrast imaging, X-ray absorption spectroscopy, and nuclear resonance fluorescence are highlighted as potential applications for laser-plasma based light sources. We discuss ongoing and future efforts to improve the properties of radiation from plasma betatron emission and Compton scattering using laser wakefield accelerators for these specific applications.

  19. Potential of Osteoblastic Cells Derived from Bone Marrow and Adipose Tissue Associated with a Polymer/Ceramic Composite to Repair Bone Tissue.

    Science.gov (United States)

    Freitas, Gileade P; Lopes, Helena B; Almeida, Adriana L G; Abuna, Rodrigo P F; Gimenes, Rossano; Souza, Lucas E B; Covas, Dimas T; Beloti, Marcio M; Rosa, Adalberto L

    2017-09-01

    One of the tissue engineering strategies to promote bone regeneration is the association of cells and biomaterials. In this context, the aim of this study was to evaluate if cell source, either from bone marrow or adipose tissue, affects bone repair induced by osteoblastic cells associated with a membrane of poly(vinylidene-trifluoroethylene)/barium titanate (PVDF-TrFE/BT). Mesenchymal stem cells (MSC) were isolated from rat bone marrow and adipose tissue and characterized by detection of several surface markers. Also, both cell populations were cultured under osteogenic conditions and it was observed that MSC from bone marrow were more osteogenic than MSC from adipose tissue. The bone repair was evaluated in rat calvarial defects implanted with PVDF-TrFE/BT membrane and locally injected with (1) osteoblastic cells differentiated from MSC from bone marrow, (2) osteoblastic cells differentiated from MSC from adipose tissue or (3) phosphate-buffered saline. Luciferase-expressing osteoblastic cells derived from bone marrow and adipose tissue were detected in bone defects after cell injection during 25 days without difference in luciferin signal between cells from both sources. Corroborating the in vitro findings, osteoblastic cells from bone marrow combined with the PVDF-TrFE/BT membrane increased the bone formation, whereas osteoblastic cells from adipose tissue did not enhance the bone repair induced by the membrane itself. Based on these findings, it is possible to conclude that, by combining a membrane with cells in this rat model, cell source matters and that bone marrow could be a more suitable source of cells for therapies to engineer bone.

  20. Collagen: A review on its sources and potential cosmetic applications.

    Science.gov (United States)

    Avila Rodríguez, María Isabela; Rodríguez Barroso, Laura G; Sánchez, Mirna Lorena

    2018-02-01

    Collagen is a fibrillar protein that conforms the conjunctive and connective tissues in the human body, essentially skin, joints, and bones. This molecule is one of the most abundant in many of the living organisms due to its connective role in biological structures. Due to its abundance, strength and its directly proportional relation with skin aging, collagen has gained great interest in the cosmetic industry. It has been established that the collagen fibers are damaged with the pass of time, losing thickness and strength which has been strongly related with skin aging phenomena [Colágeno para todo. 60 y más. 2016. http://www.revista60ymas.es/InterPresent1/groups/revistas/documents/binario/ses330informe.pdf.]. As a solution, the cosmetic industry incorporated collagen as an ingredient of different treatments to enhance the user youth and well-being, and some common presentations are creams, nutritional supplement for bone and cartilage regeneration, vascular and cardiac reconstruction, skin replacement, and augmentation of soft skin among others [J App Pharm Sci. 2015;5:123-127]. Nowadays, the biomolecule can be obtained by extraction from natural sources such as plants and animals or by recombinant protein production systems including yeast, bacteria, mammalian cells, insects or plants, or artificial fibrils that mimic collagen characteristics like the artificial polymer commercially named as KOD. Because of its increased use, its market size is valued over USD 6.63 billion by 2025 [Collagen Market By Source (Bovine, Porcine, Poultry, Marine), Product (Gelatin, Hydrolyzed Collagen), Application (Food & Beverages, Healthcare, Cosmetics), By Region, And Segment Forecasts, 2014 - 2025. Grand View Research. http://www.grandviewresearch.com/industry-analysis/collagen-market. Published 2017.]. Nevertheless, there has been little effort on identifying which collagen types are the most suitable for cosmetic purposes, for which the present review will try to enlighten

  1. Oxygen isotope composition of the bone phosphate of Australian kangaroos: Potential as a palaeoenvironmental recorder

    Science.gov (United States)

    Ayliffe, Linda K.; Chivas, Allan R.

    1990-09-01

    δ 18O determinations of bone phosphate (δ 18O p) have been performed on a suite of modern kangaroos and wallabies (known collectively as Macropods) that come from a wide variety of climatic zones within Australia. Macropod δ 18O p values range from 16 to over 30%. (V-SMOW) and are found to correlate with environmental relative humidities. As Macropods are herbivorous mammals with low drinking water requirements that consume large amounts of plant leaf water, it is likely that the δ 18O p signature of Macropods is reflecting leaf water fractionation processes that are controlled by relative humidity. These results indicate that δ 18O p from fossil bones of Macropods and similar drought-tolerant herbivorous mammals may yield palaeohumidity estimates.

  2. Potential association of posttraumatic stress disorder and decreased bone mineral density in repatriated prisoners of war.

    Science.gov (United States)

    Hain, Robert E; Hoyt, Robert E; Moore, Jeffrey L; Linnville, Steven; Segovia, Francine; Ambrose, Michael R

    2011-03-01

    We conducted a retrospective evaluation of bone mineral density data collected during routine medical follow-up evaluations of 241 Vietnam-era male repatriated prisoners of war, with and without the lifetime diagnosis of posttraumatic stress disorder (PTSD), and 79 subjects in a comparison group. Dual-energy X-ray absorptiometry scans evaluated total hip and lumbar spine T-scores. A multivariate analysis of covariance was performed on the data using age, body mass index, ethnicity, and reported alcohol consumption as covariates. There was a significant effect of group on total hip, but not lumbar spine, T-scores. Pairwise comparisons revealed statistically lower total hip T-scores in repatriates with a lifetime history of PTSD in comparison to both the comparison group and repatriates without a lifetime history of PTSD. In this study of elderly repatriated prisoners of war, we noted an association between a lifelong history of PTSD and decreased bone mineral density at the hip.

  3. Actinide(IV) Deposits on Bone: Potential Role of the Osteopontin-Thorium Complex.

    Science.gov (United States)

    Creff, Gaëlle; Safi, Samir; Roques, Jérôme; Michel, Hervé; Jeanson, Aurélie; Solari, Pier-Lorenzo; Basset, Christian; Simoni, Eric; Vidaud, Claude; Den Auwer, Christophe

    2016-01-04

    In case of a nuclear event, contamination (broad or limited) of the population or of specific workers might occur. In such a senario, the fate of actinide contaminants may be of first concern, in particular with regard to human target organs like the skeleton. To improve our understanding of the toxicological processes that might take place, a mechanistic approach is necessary. For instance, ∼50% of Pu(IV) is known from biokinetic data to accumulate in bone, but the underlining mechanisms are almost unknown. In this context, and to obtain a better description of the toxicological mechanisms associated with actinides(IV), we have undertaken the investigation, on a molecular scale, of the interaction of thorium(IV) with osteopontin (OPN) a hyperphosphorylated protein involved in bone turnover. Thorium is taken here as a simple model for actinide(IV) chemistry. In addition, we have selected a phosphorylated hexapeptide (His-pSer-Asp-Glu-pSer-Asp-Glu-Val) that is representative of the peptidic sequence involved in the bone interaction. For both the protein and the biomimetic peptide, we have determined the local environment of Th(IV) within the bioactinidic complex, combining isothermal titration calorimetry, attenuated total reflectance Fourier transform infrared spectroscopy, theoretical calculations with density functional theory, and extended X-ray absorption fine structure spectroscopy at the Th LIII edge. The results demonstrate a predominance of interaction of metal with the phosphate groups and confirmed the previous physiological studies that have highlighted a high affinity of Th(IV) for the bone matrix. Data are further compared with those of the uranyl case, representing the actinyl(V) and actinyl(VI) species. Last, our approach shows the importance of developing simplified systems [Th(IV)-peptide] that can serve as models for more biologically relevant systems.

  4. Tocilizumab potentially prevents bone loss in patients with anticitrullinated protein antibody-positive rheumatoid arthritis.

    Directory of Open Access Journals (Sweden)

    Yi-Ming Chen

    Full Text Available Rheumatoid arthritis (RA is associated with a high risk of osteoporosis and fracture. Interleukin (IL-6 inhibitors may suppress osteoclast activation. Anticitrullinated protein antibody (ACPA titers are inversely associated with bone mineral density (BMD. However, the differential effect of ACPA on bone turnover marker (BTM and BMD changes after IL-6 inhibition remains unclear. This prospective study recruited patients with active RA with inadequate response to methotrexate or biologics. BMD was measured before and after 2-year tocilizumab (TCZ treatment. Serum osteocalcin, N-terminal propeptide of type I collagen (P1NP, and C-terminal cross-linking telopeptide of type I collagen (CTX levels were assessed at the baseline and after treatment. We enrolled 76 patients with RA (89.5% women, age: 57.2 ± 13.3 years receiving TCZ. The 28-joint disease activity score was negatively correlated with BMD and T-scores of the lumbar spine and bilateral femoral neck. ACPA-positive patients had lower lumbar spine and femoral neck T-scores. After 2-year TCZ treatment, CTX levels significantly decreased (0.32 ± 0.21 vs. 0.26 ± 0.17, p = 0.038. Femoral neck BMD increased significantly (0.71 ± 0.22 vs. 0.69 ± 0.55, p = 0.008. Decreased CTX levels and improved BMD were observed only in ACPA-positive patients. After treatment, femoral neck BMD significantly increased only in patients receiving a glucocorticoid dose of ≥5 mg/day. Two-year TCZ treatment reduced bone resorption and increased femoral BMD in ACPA-positive patients. The net effects of glucocorticoids and IL-6 inhibition on BMD imply that strict inflammation control might affect bone metabolism.

  5. Instrumentation for Investigating the Regenerative Potential of Bone-Tissue-Engineered Scaffolds

    Science.gov (United States)

    2015-05-12

    Differential Scanning Calorimetry (DSC), and for chemical structure using Fourier Transform Infrared Spectroscopy ( FTIR ). (a) Papers published in peer...0.63 dL/g was obtained from Lactel Absorbable Polymers (AL, USA). PCL polymer with an inherent viscosity 1.15 dL/g aws obtained from Durect Corporation...Fourier Transform Infrared Spectroscopy ( FTIR ). Introduction With the continual aging of the population in the United States, bone fractures and

  6. Tunable resistive pulse sensing: potential applications in nanomedicine.

    Science.gov (United States)

    Sivakumaran, Muttuswamy; Platt, Mark

    2016-08-01

    An accurate characterization of nanomaterials used in clinical diagnosis and therapeutics is of paramount importance to realize the full potential of nanotechnology in medicine and to avoid unexpected and potentially harmful toxic effects due to these materials. A number of technical modalities are currently in use to study the physical, chemical and biological properties of nanomaterials but they all have advantages and disadvantages. In this review, we discuss the potential of a relative newcomer, tunable resistive pulse sensing, for the characterization of nanomaterials and its applications in nanodiagnostics.

  7. Investigations of genotoxic potential of levamisole hydrochloride in bone marrow cells of Wistar rats

    Directory of Open Access Journals (Sweden)

    Kulić Milan

    2006-01-01

    Full Text Available An experiment was performed under in vivo conditions on bone marrow cells of Wistar rats. The following doses of levamisole hydrochloride were tested: a therapeutic dose of 2.2 mg/kg bm, a dose of 4.4 mg/kg bm, LD50 -25% mg/kg bm, and LD50 -75% mg/kg bm. We followed the effect of levamisole hydrochloride on kinetics of the cell cycle and the appearance of structural and numeric changes in chromosomes in bone marrow cells. The therapeutic dose of levamisole of 2.2 mg/kg bm exhibited a capability to increase mitotic activity in the observed cells, thus confirming knowledge of the immunostimulative effect of this dose of the medicine under in vivo conditions. The other tested doses of levamisole in this experiment, observed in comparison with the control group, had an opposite effect, namely, they caused a reduction in the mitotic activity of bone marrow cells. All the examined doses in vivo exhibited the ability to induce numeric (aneuploid and polyploid and structural (lesions, breaks and insertions chromosomal aberrations. It can be concluded on the grounds of these findings that the examined doses have a genotoxic effect.

  8. A Novel Composite PMMA-based Bone Cement with Reduced Potential for Thermal Necrosis.

    Science.gov (United States)

    Lv, Yang; Li, Ailing; Zhou, Fang; Pan, Xiaoyu; Liang, Fuxin; Qu, Xiaozhong; Qiu, Dong; Yang, Zhenzhong

    2015-06-03

    Percutaneous vertebroplasty (VP) and balloon kyphoplasty (BKP) are now widely used to treat patients who suffer painful vertebral compression fractures. In each of these treatments, a bone cement paste is injected into the fractured vertebral body/bodies, and the cement of choice is a poly(methyl methacrylate) (PMMA) bone cement. One drawback of this cement is the very high exothermic temperature, which, it has been suggested, causes thermal necrosis of surrounding tissue. In the present work, we prepared novel composite PMMA bone cement where microcapsules containing a phase change material (paraffin) (PCMc) were mixed with the powder of the cement. A PCM absorbs generated heat and, as such, its presence in the cement may lead to reduction in thermal necrosis. We determined a number of properties of the composite cement. Compared to the values for a control cement (a commercially available PMMA cement used in VP and BKP), each composite cement was found to have significantly lower maximum exothermic temperature, increased setting time, significantly lower compressive strength, significantly lower compressive modulus, comparable biocompatibility, and significantly smaller thermal necrosis zone. Composite cement containing 20% PCMc may be suitable for use in VP and BKP and thus deserves further evaluation.

  9. Highly stressed carbon film coatings on silicon potential applications

    CERN Multimedia

    Sharda, T

    2002-01-01

    The fabrication of highly stressed and strongly adhered nanocrystalline diamond films on Si substrates is presented. A microwave plasma CVD method with controlled and continuous bias current density was used to grow the films. The stress/curvature of the films can be varied and controlled by altering the BCD. Potential applications for these films include particle physics and x-ray optics.

  10. Polymeric Systems of Antimicrobial Peptides—Strategies and Potential Applications

    Directory of Open Access Journals (Sweden)

    Ewa Olędzka

    2013-11-01

    Full Text Available The past decade has seen growing interest in the investigation of peptides with antimicrobial activity (AMPs. One approach utilized in infection control is incorporation of antimicrobial agents conjugated with the polymers. This review presents the recent developments on polymeric AMP carriers and their potential applications in the biomedical and pharmaceutical fields.

  11. Properties of glucoside 3-dehydrogenase and its potential applications

    African Journals Online (AJOL)

    These 3-ketoglucosides are useful as building blocks for chemicals such as detergents and polymers. The versatile glucoside 3-dehydrogenase has potential applications in different fields including sugar industry, clinical diagnosis and pharmaceutical intermediates synthesis. This review attempts to describe the glucoside ...

  12. Brewer's spent grain: A review of its potentials and applications ...

    African Journals Online (AJOL)

    Brewer's spent grain: A review of its potentials and applications. S Aliyu, M Bala. Abstract. Most developing nations continuously produce abundant agro-industrial residues such as brewer's spent grain (BSG), which are underexploited. BSG as the main by-product of brewing industry, representing approximately 85% of ...

  13. Potential applications of electron emission membranes in medicine

    Energy Technology Data Exchange (ETDEWEB)

    Bilevych, Yevgen [Fraunhofer Institute for Reliability and Microintegration (IZM), Berlin (Germany); University of Bonn, Bonn (Germany); Brunner, Stefan E. [Delft University of Technology, Delft (Netherlands); Stefan Meyer Institute for Subatomic Physics, Austrian Academy of Sciences, Vienna (Austria); Chan, Hong Wah; Charbon, Edoardo [Delft University of Technology, Delft (Netherlands); Graaf, Harry van der, E-mail: vdgraaf@nikhef.nl [Delft University of Technology, Delft (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); Hagen, Cornelis W. [Delft University of Technology, Delft (Netherlands); Nützel, Gert; Pinto, Serge D. [Photonis, Roden (Netherlands); Prodanović, Violeta [Delft University of Technology, Delft (Netherlands); Rotman, Daan [Delft University of Technology, Delft (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); University of Amsterdam, Amsterdam (Netherlands); Santagata, Fabio [State Key Lab for Solid State Lighti Changzhou base, F7 R& D HUB 1, Science and Education Town, Changzhou 213161, Jangsu Province (China); Sarro, Lina; Schaart, Dennis R. [Delft University of Technology, Delft (Netherlands); Sinsheimer, John; Smedley, John [Brookhaven National Laboratory, Upton, NY (United States); Tao, Shuxia; Theulings, Anne M.M.G. [Delft University of Technology, Delft (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands)

    2016-02-11

    With a miniaturised stack of transmission dynodes, a noise free amplifier is being developed for the detection of single free electrons, with excellent time- and 2D spatial resolution and efficiency. With this generic technology, a new family of detectors for individual elementary particles may become possible. Potential applications of such electron emission membranes in medicine are discussed.

  14. Properties of glucoside 3-dehydrogenase and its potential applications

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-29

    Dec 29, 2008 ... potential applications in different fields including sugar industry, clinical diagnosis and pharmaceutical intermediates synthesis. .... with an overall yield of 30% by column chromatography on DEAE- and CM-Sepharose .... As far as G3DH is concerned, effect of metal ions on the enzyme activity in many ...

  15. Potential application of urea-derived herbicides as cytokinins in ...

    Indian Academy of Sciences (India)

    MADU

    reported that aromatic ureas with 2-substituted and 2,6- disubstituted-4-pyridyl moiety ... [Srinivasan M, Nachiappan V and Rajasekharan R 2006 Potential application of urea-derived herbicides as cytokinins in plant tissue culture;. J. Biosci. ..... propagation of Coleus forskohlii Briq., a threatened medicinal plant; Plant Cell ...

  16. Application of potential harmonic expansion method to BEC ...

    Indian Academy of Sciences (India)

    61–74. Application of potential harmonic expansion method to BEC: Thermodynamic properties of trapped 23Na atoms. ANASUYA KUNDU1, BARNALI CHAKRABARTI2 and TAPAN KUMAR DAS1. 1Department of Physics, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India. 2Department of Physics, K.N. College ...

  17. Potential diagnostic applications of biosensors: current and future directions

    OpenAIRE

    Song, Shiping; Xu, Hui; Fan, Chunhai

    2006-01-01

    This review describes recent advances in biosensors of potential clinical applications. Biosensors are becoming increasingly important and practical tools in pathogen detection, molecular diagnostics, environmental monitoring, food safety control as well as in homeland defense. Electrochemical biosensors are particularly promising toward these goals arising due to several combined advantages including low-cost, operation convenience, and miniaturized devices. We review the clinical applicatio...

  18. Preparation and evaluation of an Arg-Gly-Asp-modified chitosan/hydroxyapatite scaffold for application in bone tissue engineering.

    Science.gov (United States)

    Chen, Lin; Li, Baolin; Xiao, Xiao; Meng, Qinggang; Li, Wei; Yu, Qian; Bi, Jiaqi; Cheng, Yong; Qu, Zhiwei

    2015-11-01

    Bone tissue engineering has become a promising method for the repair of bone defects, and the production of a scaffold with high cell affinity and osseointegrative properties is crucial for successful bone substitute. Chitosan (CS)/hydroxyapatite (HA) composite was prepared by in situ compositing combined with lyophilization, and further modified by arginine‑glycine‑aspartic acid (RGD) via physical adsorption. In order to evaluate the cell adhesion rate, viability, morphology, and alkaline phosphatase (ALP) activity, the RGD‑CS/HA scaffold was seeded with bone marrow stromal cells (BMSCs). The osseointegrative properties of the RGD‑CS/HA scaffold were evaluated by in vivo heterotopic ossification and in vivo bone defect repair. After 4 h culture with the RGD‑CS/HA scaffold, the adhesion rate of the BMSCs was 80.7%. After 3 days, BMSCs were fusiform in shape and evenly distributed on the RGD‑CS/HA scaffold. Formation of extracellular matrix and numerous cell‑cell interactions were observed after 48 h of culture, with an ALP content of 0.006 ± 0.0008 U/l/ng. Furthermore, the osseointegrative ability and biomechanical properties of the RGD‑CS/HA scaffold were comparable to that of normal bone tissue. The biocompatibility, cytocompatibility, histocompatibility and osseointegrative properties of the RGD‑CS/HA scaffold support its use in bone tissue engineering applications.

  19. Increasing Dietary Phosphorus Intake from Food Additives: Potential for Negative Impact on Bone Health123

    Science.gov (United States)

    Takeda, Eiji; Yamamoto, Hironori; Yamanaka-Okumura, Hisami; Taketani, Yutaka

    2014-01-01

    It is important to consider whether habitual high phosphorus intake adversely affects bone health, because phosphorus intake has been increasing, whereas calcium intake has been decreasing in dietary patterns. A higher total habitual dietary phosphorus intake has been associated with higher serum parathyroid hormone (PTH) and lower serum calcium concentrations in healthy individuals. Higher serum PTH concentrations have been shown in those who consume foods with phosphorus additives. These findings suggest that long-term dietary phosphorus loads and long-term hyperphosphatemia may have important negative effects on bone health. In contrast, PTH concentrations did not increase as a result of high dietary phosphorus intake when phosphorus was provided with adequate amounts of calcium. Intake of foods with a ratio of calcium to phosphorus close to that found in dairy products led to positive effects on bone health. Several randomized controlled trials have shown positive relations between dairy intake and bone mineral density. In our loading test with a low-calcium, high-phosphorus lunch provided to healthy young men, serum PTH concentrations showed peaks at 1 and 6 h, and serum fibroblast growth factor 23 (FGF23) concentrations increased significantly at 8 h after the meal. In contrast, the high-calcium, high-phosphorus meal suppressed the second PTH and FGF23 elevations until 8 h after the meal. This implies that adequate dietary calcium intake is needed to overcome the interfering effects of high phosphorus intake on PTH and FGF23 secretion. FGF23 acts on the parathyroid gland to decrease PTH mRNA and PTH secretion in rats with normal kidney function. However, increased serum FGF23 is an early alteration of mineral metabolism in chronic kidney disease, causing secondary hyperthyroidism, and implying resistance of the parathyroid gland to the action of FGF23 in chronic kidney disease. These findings suggest that long-term high-phosphorus diets may impair bone health

  20. Increasing dietary phosphorus intake from food additives: potential for negative impact on bone health.

    Science.gov (United States)

    Takeda, Eiji; Yamamoto, Hironori; Yamanaka-Okumura, Hisami; Taketani, Yutaka

    2014-01-01

    It is important to consider whether habitual high phosphorus intake adversely affects bone health, because phosphorus intake has been increasing, whereas calcium intake has been decreasing in dietary patterns. A higher total habitual dietary phosphorus intake has been associated with higher serum parathyroid hormone (PTH) and lower serum calcium concentrations in healthy individuals. Higher serum PTH concentrations have been shown in those who consume foods with phosphorus additives. These findings suggest that long-term dietary phosphorus loads and long-term hyperphosphatemia may have important negative effects on bone health. In contrast, PTH concentrations did not increase as a result of high dietary phosphorus intake when phosphorus was provided with adequate amounts of calcium. Intake of foods with a ratio of calcium to phosphorus close to that found in dairy products led to positive effects on bone health. Several randomized controlled trials have shown positive relations between dairy intake and bone mineral density. In our loading test with a low-calcium, high-phosphorus lunch provided to healthy young men, serum PTH concentrations showed peaks at 1 and 6 h, and serum fibroblast growth factor 23 (FGF23) concentrations increased significantly at 8 h after the meal. In contrast, the high-calcium, high-phosphorus meal suppressed the second PTH and FGF23 elevations until 8 h after the meal. This implies that adequate dietary calcium intake is needed to overcome the interfering effects of high phosphorus intake on PTH and FGF23 secretion. FGF23 acts on the parathyroid gland to decrease PTH mRNA and PTH secretion in rats with normal kidney function. However, increased serum FGF23 is an early alteration of mineral metabolism in chronic kidney disease, causing secondary hyperthyroidism, and implying resistance of the parathyroid gland to the action of FGF23 in chronic kidney disease. These findings suggest that long-term high-phosphorus diets may impair bone health

  1. Local Application of Isogenic Adipose-Derived Stem Cells Restores Bone Healing Capacity in a Type 2 Diabetes Model.

    Science.gov (United States)

    Wallner, Christoph; Abraham, Stephanie; Wagner, Johannes Maximilian; Harati, Kamran; Ismer, Britta; Kessler, Lukas; Zöllner, Hannah; Lehnhardt, Marcus; Behr, Björn

    2016-06-01

    Bone regeneration is typically a reliable process without scar formation. The endocrine disease type 2 diabetes prolongs and impairs this healing process. In a previous work, we showed that angiogenesis and osteogenesis-essential steps of bone regeneration-are deteriorated, accompanied by reduced proliferation in type 2 diabetic bone regeneration. The aim of the study was to improve these mechanisms by local application of adipose-derived stem cells (ASCs) and facilitate bone regeneration in impaired diabetic bone regeneration. The availability of ASCs in great numbers and the relative ease of harvest offers unique advantages over other mesenchymal stem cell entities. A previously described unicortical tibial defect model was utilized in diabetic mice (Lepr(db-/-)). Isogenic mouse adipose-derived stem cells (mASCs)(db-/db-) were harvested, transfected with a green fluorescent protein vector, and isografted into tibial defects (150,000 living cells per defect). Alternatively, control groups were treated with Dulbecco's modified Eagle's medium or mASCs(WT). In addition, wild-type mice were identically treated. By means of immunohistochemistry, proteins specific for angiogenesis, cell proliferation, cell differentiation, and bone formation were analyzed at early (3 days) and late (7 days) stages of bone regeneration. Additionally, histomorphometry was performed to examine bone formation rate and remodeling. Histomorphometry revealed significantly increased bone formation in mASC(db-/db-)-treated diabetic mice as compared with the respective control groups. Furthermore, locally applied mASCs(db-/db-) significantly enhanced neovascularization and osteogenic differentiation. Moreover, bone remodeling was upregulated in stem cell treatment groups. Local application of mACSs can restore impaired diabetic bone regeneration and may represent a therapeutic option for the future. This study showed that stem cells obtained from fat pads of type 2 diabetic mice are capable of

  2. Development of multisubstituted hydroxyapatite nanopowders as biomedical materials for bone tissue engineering applications.

    Science.gov (United States)

    Baba Ismail, Yanny M; Wimpenny, Ian; Bretcanu, Oana; Dalgarno, Kenneth; El Haj, Alicia J

    2017-06-01

    Ionic substitutions have been proposed as a tool to control the functional behavior of synthetic hydroxyapatite (HA), particularly for Bone Tissue Engineering applications. The effect of simultaneous substitution of different levels of carbonate (CO 3 ) and silicon (Si) ions in the HA lattice was investigated. Furthermore, human bone marrow-derived mesenchymal stem cells (hMSCs) were cultured on multi-substituted HA (SiCHA) to determine if biomimetic chemical compositions were osteoconductive. Of the four different compositions investigates, SiCHA-1 (0.58 wt % Si) and SiCHA-2 (0.45 wt % Si) showed missing bands for CO 3 and Si using FTIR analysis, indicating competition for occupation of the phosphate site in the HA lattice; 500°C was considered the most favorable calcination temperature as: (i) the powders produced possessed a similar amount of CO 3 (2-8 wt %) and Si (<1.0 wt %) as present in native bone; and (ii) there was a minimal loss of CO 3 and Si from the HA structure to the surroundings during calcination. Higher Si content in SiCHA-1 led to lower cell viability and at most hindered proliferation, but no toxicity effect occurred. While, lower Si content in SiCHA-2 showed the highest ALP/DNA ratio after 21 days culture with hMSCs, indicating that the powder may stimulate osteogenic behavior to a greater extent than other powders. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1775-1785, 2017. © 2017 Wiley Periodicals, Inc.

  3. A Suitable Method for DNA Extraction from Bones for Forensic Applications: A Case Study

    Directory of Open Access Journals (Sweden)

    Aqeela S. Abuidrees

    2016-06-01

    Full Text Available Human identification techniques are constantly developing. Before the discovery of DNA, anthropology accompanied with odontology was the most applicable technique for human identification. With the new era of molecular biology and the revolution of DNA and PCR techniques, DNA profiling has become the core of the human forensic identification process. Different types of samples can be exploited in forensic DNA analysis. In some extreme cases, bone samples are the only accessible samples of DNA due to the bad conditions of putrefaction or degradation of other biological materials and tissues. Therefore, an appropriate method should be determined to yield a full and clean profile. A case study is presented here in order to identify human remains and conclude the most appropriate method of DNA extraction from human remains. In addition, this study looks at the best part of the skeletal remains to be considered in the extraction of DNA for the purposes of identification. A suspect admitted that he buried his aborted son six months ago. The remains were recovered and DNA analysis was performed in order to determine any genetic link of the remains to the suspect and the female who delivered the baby. Two extraction methods were compared, the standard organic (phenol:chloroform:isoamyl alcohol and automated extraction using magnetic beads coated with silica (Qiagen EZ1 Advanced XL. Two bone parts, femur and clavicle, were also compared in terms of DNA yield. The efficiency of the two methods of DNA extraction from bones is illustrated quantitatively and qualitatively. Paternity testing was performed and the suspect was excluded from being the alleged father.

  4. Potential energy savings by using direct current for residential applications

    DEFF Research Database (Denmark)

    Diaz, Enrique Rodriguez; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2017-01-01

    This paper presents a study of the potential energy savings by implementing dc distribution systems for residential applications. In general, it is commonly accepted that the use of dc voltage improves the efficiency of the distribution, due to a decrease in the conduction losses and an efficiency...... improvement in the power converter units. However, for residential applications, the efficiency is not always improved. A grid connected residential microgrid, with renewable energy sources (RES), energy storage systems (ESS) and local loads, is presented in this work. The microgrid has been modelled...... loads. However, for isolated microgrids, the use of dc voltage has the potential to bring a significant efficiency improvement. Nevertheless the potential for cost reduction in all scenarios is very promising....

  5. Locust bean gum: Exploring its potential for biopharmaceutical applications

    Directory of Open Access Journals (Sweden)

    Marita Dionísio

    2012-01-01

    Full Text Available Polysaccharides have been finding, in the last decades, very interesting and useful applications in the biomedical and, specifically, in the biopharmaceutical field. Locust bean gum is a polysaccharide belonging to the group of galactomannans, being extracted from the seeds of the carob tree (Ceratonia siliqua. This polymer displays a number of appealing characteristics for biopharmaceutical applications, among which its high gelling capacity should be highlighted. In this review, we describe critical aspects of locust bean gum, contributing for its role in biopharmaceutical applications. Physicochemical properties, as well as strong and effective synergies with other biomaterials are described. The potential for in vivo biodegradation is explored and the specific biopharmaceutical applications are discussed.

  6. Application of modern computer-aided technologies in the production of individual bone graft: A case report

    Directory of Open Access Journals (Sweden)

    Mirković Siniša

    2015-01-01

    Full Text Available Introduction. An autologous bone (bone derived from the patient himself is considered to be a “golden standard” in the treatment of bone defects and partial atrophic alveolar ridge. However, large defects and bone losses are difficult to restore in this manner, because extraction of large amounts of autologous tissue can cause donor-site problems. Alternatively, data from computed tomographic (CT scan can be used to shape a precise 3D homologous bone block using a computer-aided design-computer-aided manufacturing (CAD-CAM system. Case report. A 63-year old male patient referred to the Clinic of Dentistry of Vojvodina in Novi Sad, because of teeth loss in the right lateral region of the lower jaw. Clinical examination revealed a pronounced resorption of the residual ridge of the lower jaw in the aforementioned region, both horizontal and vertical. After clinical examination, the patient was referred for 3D cone beam (CBCT scan that enables visualization of bony structures and accurate measurement of dimensions of the residual alveolar ridge. Considering the large extent of bone resorption, the required ridge augmentation was more than 3 mm in height and 2 mm in width along the length of some 2 cm, thus the use of granular material was excluded. After consulting prosthodontists and engineers from the Faculty of Technical Sciences in Novi Sad we decided to fabricate an individual (custom bovine-derived bone graft designed according to the obtained 3D CBCT scan. Conclusion. Application of 3D CBCT images, computer-aided systems and software in manufacturing custom bone grafts represents the most recent method of guided bone regeneration. This method substantially reduces time of recovery and carries minimum risk of postoperative complications, yet the results fully satisfy the requirements of both the patient and the therapist.

  7. A Review of Injectable Polymeric Hydrogel Systems for Application in Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Pariksha J. Kondiah

    2016-11-01

    Full Text Available Biodegradable, stimuli-responsive polymers are essential platforms in the field of drug delivery and injectable biomaterials for application of bone tissue engineering. Various thermo-responsive hydrogels display water-based homogenous properties to encapsulate, manipulate and transfer its contents to the surrounding tissue, in the least invasive manner. The success of bioengineered injectable tissue modified delivery systems depends significantly on their chemical, physical and biological properties. Irrespective of shape and defect geometry, injectable therapy has an unparalleled advantage in which intricate therapy sites can be effortlessly targeted with minimally invasive procedures. Using material testing, it was found that properties of stimuli-responsive hydrogel systems enhance cellular responses and cell distribution at any site prior to the transitional phase leading to gelation. The substantially hydrated nature allows significant simulation of the extracellular matrix (ECM, due to its similar structural properties. Significant current research strategies have been identified and reported to date by various institutions, with particular attention to thermo-responsive hydrogel delivery systems, and their pertinent focus for bone tissue engineering. Research on future perspective studies which have been proposed for evaluation, have also been reported in this review, directing considerable attention to the modification of delivering natural and synthetic polymers, to improve their biocompatibility and mechanical properties.

  8. Evaluating protein incorporation and release in electrospun composite scaffolds for bone tissue engineering applications.

    Science.gov (United States)

    Briggs, Tonye; Matos, Jeffrey; Collins, George; Arinzeh, Treena Livingston

    2015-10-01

    Electrospun polymer/ceramic composites have gained interest for use as scaffolds for bone tissue engineering applications. In this study, we investigated methods to incorporate Platelet Derived Growth Factor-BB (PDGF-BB) in electrospun polycaprolactone (PCL) or PCL prepared with polyethylene oxide (PEO), where both contained varying levels (up to 30 wt %) of ceramic composed of biphasic calcium phosphates, hydroxyapatite (HA)/β-tricalcium phosphate (TCP). Using a model protein, lysozyme, we compared two methods of protein incorporation, adsorption and emulsion electrospinning. Adsorption of lysozyme on scaffolds with ceramic resulted in minimal release of lysozyme over time. Using emulsion electrospinning, lysozyme released from scaffolds containing a high concentration of ceramic where the majority of the release occurred at later time points. We investigated the effect of reducing the electrostatic interaction between the protein and the ceramic on protein release with the addition of the cationic surfactant, cetyl trimethylammonium bromide (CTAB). In vitro release studies demonstrated that electrospun scaffolds prepared with CTAB released more lysozyme or PDGF-BB compared with scaffolds without the cationic surfactant. Human mesenchymal stem cells (MSCs) on composite scaffolds containing PDGF-BB incorporated through emulsion electrospinning expressed higher levels of osteogenic markers compared to scaffolds without PDGF-BB, indicating that the bioactivity of the growth factor was maintained. This study revealed methods for incorporating growth factors in polymer/ceramic scaffolds to promote osteoinduction and thereby facilitate bone regeneration. © 2015 Wiley Periodicals, Inc.

  9. The application of rapid prototyping to improve bone reconstruction in immediate dentoalveolar restoration: a case report.

    Science.gov (United States)

    Martins da Rosa, José Carlos; Fadanelli, Marcos Alexandre; Zimmerman, Diego; de Oliveira Rosa, Ariádene Cristina Pértile

    This article describes the use of rapid prototyping (RP) for diagnosis, planning, and execution of the reconstruction of hard and soft tissue in socket defects using immediate dentoalveolar restoration (IDR). In cases of tissue loss in anterior dental areas, esthetic rehabilitation poses a major challenge with respect to treatment planning with the goal of long-term tissue maintenance. The IDR technique consists of immediate reconstruction in a single procedure of bone and soft tissue around implants placed immediately after extraction, and prosthetic rehabilitation. As this procedure is immediate and flapless, the correct diagnosis of tissue loss and correct graft adaptation are mandatory. RP can increase the precision of the procedure, as demonstrated using a clinical case characterized by total loss of the buccal bone wall and gingival recession. The results were evaluated by clinical assessment, photography, radiography, cone beam computed tomography (CBCT), and prototyping. The application of RP facilitated the execution of IDR as it enabled more accurate diagnosis of the socket defect and more precise adaptation of the tissue graft. A clinical study should be conducted to evaluate the effects of RP on the clinical results of the IDR technique.

  10. Potential National Security Applications of Nuclear Resonance Fluorescence Methods

    International Nuclear Information System (INIS)

    Warren, Glen A.; Peplowski, Patrick N.; Caggiano, Joseph A.

    2009-01-01

    The objective of this report is to document the initial investigation into the possible research issues related to the development of NRF-based national security applications. The report discusses several potential applications ranging from measuring uranium enrichment in UF6 canisters to characterization of gas samples. While these applications are varied, there are only a few research issues that need to be addressed to understand the limitation of NRF in solving these problems. These research issues range from source and detector development to measuring small samples. The next effort is to determine how best to answer the research issues, followed by a prioritization of those questions to ensure that the most important are addressed. These issues will be addressed through either analytical calculations, computer simulations, analysis of previous data or collection of new measurements. It will also be beneficial to conduct a thorough examination of a couple of the more promising applications in order to develop concrete examples of how NRF may be applied in specific situations. The goals are to develop an understanding of whether the application of NRF is limited by technology or physics in addressing national security applications, to gain a motivation to explore those possible applications, and to develop a research roadmap so that those possibilities may be made reality.

  11. Fabrication and characterization of two-layered nanofibrous membrane for guided bone and tissue regeneration application.

    Science.gov (United States)

    Masoudi Rad, Maryam; Nouri Khorasani, Saied; Ghasemi-Mobarakeh, Laleh; Prabhakaran, Molamma P; Foroughi, Mohammad Reza; Kharaziha, Mahshid; Saadatkish, Niloufar; Ramakrishna, Seeram

    2017-11-01

    Membranes used in dentistry act as a barrier to prevent invasion of intruder cells to defected area and obtains spaces that are to be subsequently filled with new bone and provide required bone volume for implant therapy when there is insufficient volume of healthy bone at implant site. In this study a two-layered bioactive membrane were fabricated by electrospinning whereas one layer provides guided bone regeneration (GBR) and fabricated using poly glycerol sebacate (PGS)/polycaprolactone (PCL) and Beta tri-calcium phosphate (β-TCP) (5, 10 and 15%) and another one containing PCL/PGS and chitosan acts as guided tissue regeneration (GTR). The morphology, chemical, physical and mechanical characterizations of the membranes were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), tensile testing, then biodegradability and bioactivity properties were evaluated. In vitro cell culture study was also carried out to investigate proliferation and mineralization of cells on different membranes. Transmission electron microscope (TEM) and SEM results indicated agglomeration of β-TCP nanoparticles in the structure of nanofibers containing 15% β-TCP. Moreover by addition of β-TCP from 5% to 15%, contact angle decreased due to hydrophilicity of nanoparticles and bioactivity was found to increase. Mechanical properties of the membrane increased by incorporation of 5% and 10% of β-TCP in the structure of nanofibers, while addition of 15% of β-TCP was found to deteriorate mechanical properties of nanofibers. Although the presence of 5% and 10% of nanoparticles in the nanofibers increased proliferation of cells on GBR layer, cell proliferation was observed to decrease by addition of 15% β-TCP in the structure of nanofibers which is likely due to agglomeration of nanoparticles in the nanofiber structure. Our overall results revealed PCL/PGS containing 10% β-TCP could be selected as the optimum GBR membrane

  12. The principle of vulnerability and its potential applications in bioethics

    Directory of Open Access Journals (Sweden)

    Demény Enikő

    2016-12-01

    Full Text Available The principle of vulnerability is a specific principle within European Bioethics. On the one hand, vulnerability expresses human limits and frailty on the other hand it represents moral and ethical action principles. In this paper a discussion on the relationship between the concepts of autonomy, vulnerability and responsibility is proposed and presentation of some possible applications of the principle of vulnerability within bioethics. In conclusion, some potential benefits of applying the principle of vulnerability as well as possible difficulties in its application are highlighted.

  13. Evaluation of Synthesized Nanohydroxyapatite-Nanocellulose Composites as Biocompatible Scaffolds for Applications in Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Claudia S. Herdocia-Lluberes

    2015-01-01

    Full Text Available Basic calcium phosphate (BCP crystals have been associated with many diseases due to their activation of signaling pathways that lead to their mineralization and deposition in intra-articular and periarticular locations in the bones. In this study, hydroxyapatite (HAp has been placed in a polysaccharide network as a strategy to minimize this deposition. This research consisted of the evaluation of varying proportions of the polysaccharide network, cellulose nanocrystals (CNCs, and HAp synthesized via a simple sol-gel method. The resulting biocompatible composites were extensively characterized by means of thermogravimetric analysis (TGA, powder X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR, dynamic light scattering (DLS, zeta potential, and scanning electron microscopy (SEM. It was found that an nHAp = CNC ratio presented greater homogeneity in the size and distribution of the nanoparticles without compromising the crystalline structure. Also, incorporation of bone morphogenetic protein 2 (BMP-2 was performed to evaluate the effects that this interaction would have in the constructs. Finally, the osteoblast cell (hFOB 1.19 viability assay was executed and it showed that all of the materials promoted greater cell proliferation while the nHAp > CNC proportion with the inclusion of the BMP-2 protein was the best composite for the purpose of this study.

  14. An application of partial least squares for identifying dietary patterns in bone health.

    Science.gov (United States)

    Yang, Tiffany C; Aucott, Lorna S; Duthie, Garry G; Macdonald, Helen M

    2017-12-01

    In a large cohort of older women, a mechanism-driven statistical technique for assessing dietary patterns that considers a potential nutrient pathway found two dietary patterns associated with lumbar spine and femoral neck bone mineral density. A "healthy" dietary pattern was observed to be beneficial for bone mineral density. Dietary patterns represent a broader, more realistic representation of how foods are consumed, compared to individual food or nutrient analyses. Partial least-squares (PLS) is a data-reduction technique for identifying dietary patterns that maximizes correlation between foods and nutrients hypothesized to be on the path to disease, is more hypothesis-driven than previous methods, and has not been applied to the study of dietary patterns in relation to bone health. Women from the Aberdeen Prospective Osteoporosis Screening Study (2007-2011, n = 2129, age = 66 years (2.2)) provided dietary intake using a food frequency questionnaire; 37 food groups were created. We applied PLS to the 37 food groups and 9 chosen response variables (calcium, potassium, vitamin C, vitamin D, protein, alcohol, magnesium, phosphorus, zinc) to identify dietary patterns associated with bone mineral density (BMD) cross-sectionally. Multivariable regression was used to assess the relationship between the retained dietary patterns and BMD at the lumbar spine and femoral neck, adjusting for age, body mass index, physical activity level, smoking, and national deprivation category. Five dietary patterns were identified, explaining 25% of the variation in food groups and 77% in the response variables. Two dietary patterns were positively associated with lumbar spine (per unit increase in factor 2: 0.012 g/cm 2 [95% CI: 0.006, 0.01]; factor 4: 0.007 g/cm 2 [95% CI: 0.00001, 0.01]) and femoral neck (factor 2: 0.006 g/cm 2 [95% CI: 0.002, 0.01]; factor 4: 0.008 g/cm 2 [95% CI: 0.003, 0.01)]) BMD. Dietary pattern 2 was characterized by high intakes of milk

  15. TLR Stimulation of Bone Marrow Lymphoid Precursors from Childhood Acute Leukemia Modifies Their Differentiation Potentials

    Directory of Open Access Journals (Sweden)

    Elisa Dorantes-Acosta

    2013-01-01

    Full Text Available Acute leukemias are the most frequent childhood malignancies worldwide and remain a leading cause of morbidity and mortality of relapsed patients. While remarkable progress has been made in characterizing genetic aberrations that may control these hematological disorders, it has also become clear that abnormalities in the bone marrow microenvironment might hit precursor cells and contribute to disease. However, responses of leukemic precursor cells to inflammatory conditions or microbial components upon infection are yet unexplored. Our previous work and increasing evidence indicate that Toll-like receptors (TLRs in the earliest stages of lymphoid development in mice and humans provide an important mechanism for producing cells of the innate immune system. Using highly controlled co-culture systems, we now show that lymphoid precursors from leukemic bone marrow express TLRs and respond to their ligation by changing cell differentiation patterns. While no apparent contribution of TLR signals to tumor progression was recorded for any of the investigated diseases, the replenishment of innate cells was consistently promoted upon in vitro TLR exposure, suggesting that early recognition of pathogen-associated molecules might be implicated in the regulation of hematopoietic cell fate decisions in childhood acute leukemia.

  16. An experimental study on the application of radionuclide imaging in repair of the bone defect

    Directory of Open Access Journals (Sweden)

    Weimin Zhu

    2011-08-01

    Full Text Available The aim of our study was to validate the effect of radionuclide imaging in early monitoring of the bone’s reconstruction, the animal model of bone defect was made on the rabbits repaired with HA artificial bone. The ability of bone defect repair was evaluated by using radionuclide bone imaging at 2, 4, 8 and 12 weeks postoperatively. The results indicate that the experimental group stimulated more bone formation than that of the control group. The differences of the bone reconstruction ability were statistically significant (p<0.05. The nano-HA artificial has good bone conduction, and it can be used for the treatment of bone defects. Radionuclide imaging may be an effective and first choice method for the early monitoring of the bone’s reconstruction.

  17. In Vitro Corrosion Assessment of Additively Manufactured Porous NiTi Structures for Bone Fixation Applications

    Directory of Open Access Journals (Sweden)

    Hamdy Ibrahim

    2018-03-01

    Full Text Available NiTi alloys possess distinct functional properties (i.e., shape memory effect and superelasticity and biocompatibility, making them appealing for bone fixation applications. Additive manufacturing offers an alternative method for fabricating NiTi parts, which are known to be very difficult to machine using conventional manufacturing methods. However, poor surface quality, and the presence of impurities and defects, are some of the major concerns associated with NiTi structures manufactured using additive manufacturing. The aim of this study is to assess the in vitro corrosion properties of additively manufactured NiTi structures. NiTi samples (bulk and porous were produced using selective laser melting (SLM, and their electrochemical corrosion characteristics and Ni ion release levels were measured and compared with conventionally fabricated NiTi parts. The additively manufactured NiTi structures were found to have electrochemical corrosion characteristics similar to those found for the conventionally fabricated NiTi alloy samples. The highest Ni ion release level was found in the case of 50% porous structures, which can be attributed to their significantly higher exposed surface area. However, the Ni ion release levels reported in this work for all the fabricated structures remain within the range of most of values for conventionally fabricated NiTi alloys reported in the literature. The results of this study suggest that the proposed SLM fabrication process does not result in a significant deterioration in the corrosion resistance of NiTi parts, making them suitable for bone fixation applications.

  18. Potential Coir Fibre Composite for Small Wind Turbine Blade Application

    Directory of Open Access Journals (Sweden)

    Bakri Bakri

    2017-03-01

    Full Text Available Natural fibers have been developed as reinforcement of composite to shift synthetic fibers. One of potential natural fibers developed is coir fiber. This paper aims to describe potential coir fiber as reinforcement of composite for small wind turbine blade application. The research shows that mechanical properties ( tensile, impact, shear, flexural and compression strengths of coir fiber composite have really similar to wood properties for small wind turbine blade material, but inferior to glass fiber composite properties. The effect of weathering was also evaluated to coir fiber composite in this paper.

  19. Click Reactions and Boronic Acids: Applications, Issues, and Potential Solutions

    Directory of Open Access Journals (Sweden)

    Chaofeng Dai

    2010-08-01

    Full Text Available Boronic acids have been widely used in a wide range of organic reactions, in the preparation of sensors for carbohydrates, and as potential pharmaceutical agents. With the growing importance of click reactions, inevitably they are also applied to the synthesis of compounds containing the boronic acid moiety. However, such applications have unique problems. Chief among them is the issue of copper-mediated boronic acid degradation in copper-assisted [2,3]-cycloadditions involving an alkyne and an azido compound as the starting materials. This review summarizes recent developments, analyzes potential issues, and discusses known as well as possible solutions.

  20. Transplantation of autologous bone marrow stromal cells (BMSC for CNS disorders – Strategy and tactics for clinical application

    Directory of Open Access Journals (Sweden)

    Satoshi Kuroda

    2010-01-01

    Full Text Available Background – There is increasing evidence that the transplanted bone marrow stromal cells (BMSC significantly promote functional recovery after central nervous system (CNS damage in the animal models of various kinds of CNS disorders, including cerebral infarct, brain contusion and spinal cord injury. However, there are several shortages of information when considering clinical application of BMSC transplantation for patients with neurological disorders. In this paper, therefore, we discuss what we should clarify to establish cell transplantation therapy in clinical situation and describe our recent works for this purpose.Methods and Results – The BMSC have the ability to alter their gene expression profile and phenotype in response to the surrounding circumstances and to protect the neurons by producing some neurotrophic factors. They also promote neurite extension and rebuild the neural circuits in the injured CNS. Using optical imaging and MRI techniques, the transplanted BMSC can non-invasively be tracked in the living animals for at least 8 weeks after transplantation. Functional imaging such as PET scan may have the potential to assess the beneficial effects of BMSC transplantation. The BMSC can be expanded using the animal protein-free culture medium, which would maintain their potential of proliferation, migration, and neural differentiation.Conclusion – It is urgent issues to develop clinical imaging technique to track the transplanted cells in the CNS and evaluate the therapeutic significance of BMSC transplantation in order to establish it as a definite therapeutic strategy in clinical situation in the future

  1. Nanotechnology in the targeted drug delivery for bone diseases and bone regeneration.

    Science.gov (United States)

    Gu, Wenyi; Wu, Chengtie; Chen, Jiezhong; Xiao, Yin

    2013-01-01

    Nanotechnology is a vigorous research area and one of its important applications is in biomedical sciences. Among biomedical applications, targeted drug delivery is one of the most extensively studied subjects. Nanostructured particles and scaffolds have been widely studied for increasing treatment efficacy and specificity of present treatment approaches. Similarly, this technique has been used for treating bone diseases including bone regeneration. In this review, we have summarized and highlighted the recent advancement of nanostructured particles and scaffolds for the treatment of cancer bone metastasis, osteosarcoma, bone infections and inflammatory diseases, osteoarthritis, as well as for bone regeneration. Nanoparticles used to deliver deoxyribonucleic acid and ribonucleic acid molecules to specific bone sites for gene therapies are also included. The investigation of the implications of nanoparticles in bone diseases have just begun, and has already shown some promising potential. Further studies have to be conducted, aimed specifically at assessing targeted delivery and bioactive scaffolds to further improve their efficacy before they can be used clinically.

  2. Market potential for non-electric applications of nuclear energy

    International Nuclear Information System (INIS)

    2002-01-01

    The objective of this report is to assess the market potential for the non-electric applications of nuclear energy in the near (before 2020) and long (2020-2050) terms. The main non-electric applications are defined here as district heating, desalination (of sea, brackish and waste water), industrial heat supply, ship propulsion and the energy supply for spacecraft. This report is principally devoted to these applications, although a less detailed assessment of some innovative applications (e.g. hydrogen production and coal gasification) is also provided. While the technical details of these applications are covered briefly, emphasis is placed on the economic and other factors that may promote or hinder the penetration of the nuclear option into the market for non-electric energy services. The report is intentionally targeted towards expected demands. It is for this reason that its sections are structured by demand categories and not according to possible reactor types. At the same time, the orientation on the demand side can result in overlaps at the supply side, because the same nuclear reactor can often serve more than one type of demand. Such cases are noted as appropriate. Each section characterizes a specific non-electric application in terms of its market size, its prospects for nuclear technologies and the economic competitiveness of the technologies

  3. TMI-2 remote cameras, teleoperators, and other potential nuclear applications

    International Nuclear Information System (INIS)

    Pavelek, M.D. II

    1987-01-01

    Evaluation, testing, and use of fixed-position, remotely operated video-camera equipment and various teleoperators at Three Mile Island Nuclear Station Unit 2 (TMI-2) have demonstrated that significant potential advantages may be obtained by installing remotely operated equipment at other nuclear facilities. Teleoperators at TMI-2 have permitted successful operations in areas not accessible to personnel. Insights gained from the remotely operated camera systems and teleoperators used and evaluated at TMI-2 are discussed from the perspective of actual applications and the potential benefits from deployment of remote devices at other nuclear facilities. Actual exposure savings achieved are not presented because these applications and resultant exposure savings are specific to TMI-2. 3 refs., 4 figs

  4. Advanced Communications Technology Satellite (ACTS) and potential system applications

    Science.gov (United States)

    Wright, David L.; Balombin, Joseph R.; Sohn, Philip Y.

    1990-01-01

    A description of the advanced communications technology satellite (ACTS) system is given with special emphasis on the communication characteristics. Potential satellite communications scenarios, including future operational ACTS-like satellite systems, are discussed. The description of the ACTS system updates previously published ACTS system references. Detailed information on items such as experimental ground stations is presented. The potential services can be generically described as voice, video, and data services. The implementation of these services on future operational ACTS-like systems can lead to unique quality, flexibility, and capacity characteristics at lower service costs. The specific service applications that could be supported range from low to high data rates and include both domestic and international applications.

  5. Potential applications of nanostructured materials in nuclear waste management.

    Energy Technology Data Exchange (ETDEWEB)

    Braterman, Paul S. (The University of North Texas, Denton, TX); Phol, Phillip Isabio; Xu, Zhi-Ping (The University of North Texas, Denton, TX); Brinker, C. Jeffrey; Yang, Yi (University of New Mexico, Albuquerque, NM); Bryan, Charles R.; Yu, Kui; Xu, Huifang (University of New Mexico, Albuquerque, NM); Wang, Yifeng; Gao, Huizhen

    2003-09-01

    This report summarizes the results obtained from a Laboratory Directed Research & Development (LDRD) project entitled 'Investigation of Potential Applications of Self-Assembled Nanostructured Materials in Nuclear Waste Management'. The objectives of this project are to (1) provide a mechanistic understanding of the control of nanometer-scale structures on the ion sorption capability of materials and (2) develop appropriate engineering approaches to improving material properties based on such an understanding.

  6. Synchrotron Radiation and Energy Dispersive X-Ray Fluorescence Applications on Elemental Distribution in Human Hair and Bones

    International Nuclear Information System (INIS)

    Carvalho, M.L.; Marques, A.F.; Brito, J.

    2003-01-01

    This work is an application of synchrotron microprobe X- Ray fluorescence in order to study elemental distribution along human hair samples of contemporary citizens. Furthermore, X-Ray fluorescence spectrometry is also used to analyse human bones of different historical periods: Neolithic and contemporary subjects. The elemental content in the bones allowed us to conclude about environmental contamination, dietary habits and health status influence in the corresponding citizens. All samples were collected post-mortem. Quantitative analysis was performed for Mn, Fe, Co, Ni, Cu, Zn, Br, Rb, Sr and Pb. Mn and Fe concentration were much higher in bones from pre-historic periods. On the contrary, Pb bone concentrations of contemporary subjects are much higher than in pre-historical ones, reaching 100 μg g-1, in some cases. Very low concentrations for Co, Ni, Br and Rb were found in all the analysed samples. Cu concentrations, allows to distinguish Chalcolithic bones from the Neolithic ones. The distribution of trace elements along human hair was studied for Pb and the obtained pattern was consistent with the theoretical model, based on the diffusion of this element from the root and along the hair. Therefore, the higher concentrations in hair for Pb of contemporary individuals were also observed in the bones of citizens of the same sampling sites. All samples were analysed directly without any chemical treatment

  7. Potential applications of bioprocess technology in petroleum industry.

    Science.gov (United States)

    Singh, Ajay; Singh, Brajesh; Ward, Owen

    2012-11-01

    Petroleum refining is traditionally based on the use of physicochemical processes such as distillation and chemical catalysis that operate under high temperatures and pressures conditions, which are energy intensive and costly. Biotechnology has become an important tool for providing new approaches in petroleum industry during oil production, refining and processing as well as managing environmentally safe pollutant remediation and disposal practices. Earlier biotechnology applications in the petroleum industry were limited to microbial enhanced oil recovery, applications of bioremediation to contaminated marine shorelines, soils and sludges. The potential role of bioprocess technology in this industry has now expanded further into the areas of biorefining and upgrading of fuels, production of fine chemicals, control of souring during production and air VOC biofiltration. In this paper we provide an overview of the major applications of bioprocesses and technology development in the petroleum industry both in upstream and downstream areas and highlight future challenges and opportunities.

  8. Potential Applications of Zeolite Membranes in Reaction Coupling Separation Processes

    Science.gov (United States)

    Daramola, Michael O.; Aransiola, Elizabeth F.; Ojumu, Tunde V.

    2012-01-01

    Future production of chemicals (e.g., fine and specialty chemicals) in industry is faced with the challenge of limited material and energy resources. However, process intensification might play a significant role in alleviating this problem. A vision of process intensification through multifunctional reactors has stimulated research on membrane-based reactive separation processes, in which membrane separation and catalytic reaction occur simultaneously in one unit. These processes are rather attractive applications because they are potentially compact, less capital intensive, and have lower processing costs than traditional processes. Therefore this review discusses the progress and potential applications that have occurred in the field of zeolite membrane reactors during the last few years. The aim of this article is to update researchers in the field of process intensification and also provoke their thoughts on further research efforts to explore and exploit the potential applications of zeolite membrane reactors in industry. Further evaluation of this technology for industrial acceptability is essential in this regard. Therefore, studies such as techno-economical feasibility, optimization and scale-up are of the utmost importance.

  9. Potential impacts of nanotechnology on energy transmission applications and needs.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.; Environmental Science Division

    2007-11-30

    The application of nanotechnologies to energy transmission has the potential to significantly impact both the deployed transmission technologies and the need for additional development. This could be a factor in assessing environmental impacts of right-of-way (ROW) development and use. For example, some nanotechnology applications may produce materials (e.g., cables) that are much stronger per unit volume than existing materials, enabling reduced footprints for construction and maintenance of electricity transmission lines. Other applications, such as more efficient lighting, lighter-weight materials for vehicle construction, and smaller batteries having greater storage capacities may reduce the need for long-distance transport of energy, and possibly reduce the need for extensive future ROW development and many attendant environmental impacts. This report introduces the field of nanotechnology, describes some of the ways in which processes and products developed with or incorporating nanomaterials differ from traditional processes and products, and identifies some examples of how nanotechnology may be used to reduce potential ROW impacts. Potential environmental, safety, and health impacts are also discussed.

  10. Potential Applications of Zeolite Membranes in Reaction Coupling Separation Processes

    Directory of Open Access Journals (Sweden)

    Tunde V. Ojumu

    2012-10-01

    Full Text Available Future production of chemicals (e.g., fine and specialty chemicals in industry is faced with the challenge of limited material and energy resources. However, process intensification might play a significant role in alleviating this problem. A vision of process intensification through multifunctional reactors has stimulated research on membrane-based reactive separation processes, in which membrane separation and catalytic reaction occur simultaneously in one unit. These processes are rather attractive applications because they are potentially compact, less capital intensive, and have lower processing costs than traditional processes. Therefore this review discusses the progress and potential applications that have occurred in the field of zeolite membrane reactors during the last few years. The aim of this article is to update researchers in the field of process intensification and also provoke their thoughts on further research efforts to explore and exploit the potential applications of zeolite membrane reactors in industry. Further evaluation of this technology for industrial acceptability is essential in this regard. Therefore, studies such as techno-economical feasibility, optimization and scale-up are of the utmost importance.

  11. Growth and Potential Damage of Human Bone-Derived Cells Cultured on Fresh and Aged C60/Ti Films

    Science.gov (United States)

    Kopova, Ivana; Lavrentiev, Vasily; Vacik, Jiri; Bacakova, Lucie

    2015-01-01

    Thin films of binary C60/Ti composites, with various concentrations of Ti ranging from ~ 25% to ~ 70%, were deposited on microscopic glass coverslips and were tested for their potential use in bone tissue engineering as substrates for the adhesion and growth of bone cells. The novelty of this approach lies in the combination of Ti atoms (i.e., widely used biocompatible material for the construction of stomatological and orthopedic implants) with atoms of fullerene C60, which can act as very efficient radical scavengers. However, fullerenes and their derivatives are able to generate harmful reactive oxygen species and to have cytotoxic effects. In order to stabilize C60 molecules and to prevent their possible cytotoxic effects, deposition in the compact form of Ti/C60 composites (with various Ti concentrations) was chosen. The reactivity of C60/Ti composites may change in time due to the physicochemical changes of molecules in an air atmosphere. In this study, we therefore tested the dependence between the age of C60/Ti films (from one week to one year) and the adhesion, morphology, proliferation, viability, metabolic activity and potential DNA damage to human osteosarcoma cells (lines MG-63 and U-2 OS). After 7 days of cultivation, we did not observe any negative influence of fresh or aged C60/Ti layers on cell behavior, including the DNA damage response. The presence of Ti atoms resulted in improved properties of the C60 layers, which became more suitable for cell cultivation. PMID:25875338

  12. Hydrogen gas treatment prolongs replicative lifespan of bone marrow multipotential stromal cells in vitro while preserving differentiation and paracrine potentials

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Haruhisa [Department of Pathology, The Ohio State University, Columbus, OH 43210 (United States); Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210 (United States); Guan, Jianjun [Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210 (United States); Tamama, Kenichi, E-mail: kenichi.tamama@osumc.edu [Department of Pathology, The Ohio State University, Columbus, OH 43210 (United States); Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210 (United States); Center for Stem Cell and Regenerative Medicine, The Ohio State University, Columbus, OH 43210 (United States)

    2010-07-02

    Cell therapy with bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) represents a promising approach in the field of regenerative medicine. Low frequency of MSCs in adult bone marrow necessitates ex vivo expansion of MSCs after harvest; however, such a manipulation causes cellular senescence with loss of differentiation, proliferative, and therapeutic potentials of MSCs. Hydrogen molecules have been shown to exert organ protective effects through selective reduction of hydroxyl radicals. As oxidative stress is one of the key insults promoting cell senescence in vivo as well as in vitro, we hypothesized that hydrogen molecules prevent senescent process during MSC expansion. Addition of 3% hydrogen gas enhanced preservation of colony forming early progenitor cells within MSC preparation and prolonged the in vitro replicative lifespan of MSCs without losing differentiation potentials and paracrine capabilities. Interestingly, 3% hydrogen gas treatment did not decrease hydroxyl radical, protein carbonyl, and 8-hydroxydeoxyguanosine, suggesting that scavenging hydroxyl radical might not be responsible for these effects of hydrogen gas in this study.

  13. Mandibular reconstruction using bone allografts

    International Nuclear Information System (INIS)

    Chang Joon Yim

    1999-01-01

    Further understanding of bone healing mechanisms, bone physiology and bone biology, transplantation immunology, and development of Tissue Banking procedures has enabled oral and maxillofacial surgeons to reconstruct even the most difficult bony defects successfully with the preserved allogeneic bone implant. Although it had been known that bone allografts were clinically effective, its application has not been widespread until the reports of Inclan (I 942), Hyatt and Butler (I 950), and Wilson (I 95 1). Tissue Banking provides the surgeon with a readily available, relatively inexpensive, and relatively safe selection of allogeneic bone for clinical use. Now autogenous bone and allogeneic bone implants present a wide variety of surgical options to surgeons, whether used separately or in combination. The surgeons are able to make judicious and fruitful choices, only with a thorough knowledge of the above-mentioned biological principles and skillful techniques. Many kinds of bone grafting techniques have been tried for reconstructing defective osseous tissues of the oral and maxillofacial region, though they have varying degrees of success. The osseous defects which require grafting include those of various size, shape, position, or amount. Unlike autogenous grafts, whose function is to provide osteogenic cells, allografts are purely passive, offering only a matrix for the inductive phase of bone healing. The condition of the recipient bed is of primary importance, because the host must produce all of the essential elements for the bone allograft to become incorporated. Depending on the processing methods of the allogeneic bone, the bone graft materials have different qualities, different healing potentials and different indications. Proper selection of grafts and surgical techniques requires an understanding of graft immunology and the mechanisms of graft healing. The surgeons should know about the biological principles to raise the clinical success rate

  14. Potential pharmacological applications of polyphenolic derivatives from marine brown algae.

    Science.gov (United States)

    Thomas, Noel Vinay; Kim, Se-Kwon

    2011-11-01

    Recently, the isolation and characterization of the biologically active components from seaweeds have gained much attention from various research groups across the world. The marine algae have been studied for biologically active components and phlorotannins are one among them. Among marine algae, brown algal species such as Ecklonia cava, Eisenia arborea, Ecklonia stolinifera and Eisenia bicyclis have been studied for their potential biological activities. Majority of the investigations on phlorotannins derived from brown algae have exhibited their potentiality as antioxidant, anti-inflammatory, antidiabetic, antitumor, antihypertensive, anti-allergic, hyaluronidase enzyme inhibition and in matrix metalloproteinases (MMPs) inhibition activity. In this review, we have made an attempt to discuss the potential biological activities of phlorotannins from marine brown algae and their possible candidature in the pharmaceutical applications. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. "Black bone" MRI: a potential alternative to CT when imaging the head and neck: report of eight clinical cases and review of the Oxford experience.

    Science.gov (United States)

    Eley, K A; Watt-Smith, S R; Golding, S J

    2012-11-01

    The potential risks associated with ionising radiation are well documented. We have previously reported the "black bone" MRI sequence, useful when imaging cortical bone. The objective of this paper is to report our initial experience of this technique in patients undergoing imaging of the head and neck region. Using the departmental database those patients having had "black bone" sequences of the head and neck performed as part of their MRI examination in the preceding 5 years were identified. The radiological reports were reviewed to identify those cases where "black bone" or conventional MRI sequences had been performed in place of the requested CT, and the patient medical records for these cases were reviewed. Medical record review was also conducted for those cases where it was considered that the pathological condition requiring imaging would ordinarily be investigated with CT. The "black bone" sequence had been performed in 69 patients as part of routine MRI of the head and neck. Of these, 67% (n=46) were performed in combination with CT imaging, the majority of cases being primary tumours. In four cases, an MRI was performed in place of the requested CT scan. We present eight clinical cases illustrating the potential benefits of the "black bone" sequence. "Black bone" MRI offers a radiation-free method of imaging the head and neck, and has been successfully utilised in a range of benign and malignant conditions affecting this region. Advances in knowledge Adoption of this approach, where feasible, would be a significant advance in radiation protection.

  16. Recent Developments of Functional Scaffolds for Craniomaxillofacial Bone Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Yukihiko Kinoshita

    2013-01-01

    Full Text Available Autogenous bone grafting remains a gold standard for the reconstruction critical-sized bone defects in the craniomaxillofacial region. Nevertheless, this graft procedure has several disadvantages such as restricted availability, donor-site morbidity, and limitations in regard to fully restoring the complicated three-dimensional structures in the craniomaxillofacial bone. The ultimate goal of craniomaxillofacial bone reconstruction is the regeneration of the physiological bone that simultaneously fulfills both morphological and functional restorations. Developments of tissue engineering in the last two decades have brought such a goal closer to reality. In bone tissue engineering, the scaffolds are fundamental, elemental and mesenchymal stem cells/osteoprogenitor cells and bioactive factors. A variety of scaffolds have been developed and used as spacemakers, biodegradable bone substitutes for transplanting to the new bone, matrices of drug delivery system, or supporting structures enhancing adhesion, proliferation, and matrix production of seeded cells according to the circumstances of the bone defects. However, scaffolds to be clinically completely satisfied have not been developed yet. Development of more functional scaffolds is required to be applied widely to cranio-maxillofacial bone defects. This paper reviews recent trends of scaffolds for crania-maxillofacial bone tissue engineering, including our studies.

  17. Potential Applications of Smart Multifunctional Wearable Materials to Gerontology.

    Science.gov (United States)

    Armstrong, David G; Najafi, Bijan; Shahinpoor, Mohsen

    2017-01-01

    Smart multifunctional materials can play a constructive role in addressing some very important aging-related issues. Aging affects the ability of older adults to continue to live safely and economically in their own residences for as long as possible. Thus, there will be a greater need for preventive, acute, rehabilitative, and long-term health care services for older adults as well as a need for tools to enable them to function independently during daily activities. The objective of this paper is, thus, to present a comprehensive review of some potential smart materials and their areas of applications to gerontology. Thus, brief descriptions of various currently available multifunctional smart materials and their possible applications to aging-related problems are presented. It is concluded that some of the most important applications to geriatrics may be in various sensing scenarios to collect health-related feedback or information and provide personalized care. Further described are the applications of wearable technologies to aging-related needs, including devices for home rehabilitation, remote monitoring, social well-being, frailty monitoring, monitoring of diabetes and wound healing and fall detection or prediction. It is also concluded that wearable technologies, when combined with an appropriate application and with appropriate feedback, may help improve activities and functions of older patients with chronic diseases. Finally, it is noted that methods developed to measure what one collectively manages in this population may provide a foundation to establish new definitions of quality of life. © 2017 S. Karger AG, Basel.

  18. [Application of minimally invasive, decompression bone graft implantation combined with metal trabecular bone reconstruction system for early stage osteonecrosis of femoral head].

    Science.gov (United States)

    Chen, Xian-tao; Tan, Xu-yi; Liu, You-wen; Zhang, Xiao-dong; Liu, Li-yun; Jia, Yu-dong

    2015-05-01

    To observe the application effect of minimally invasive decompression, bone graft implantation and metal trabecular bone reconstruction system for early stage osteonecrosis of femoral head and discuss the treatment of hip-salvage operation in early stage osteonecrosis of femoral head; From January 2010 to June 2011, 50 patients (62 hips) Which were osteonecrosis of femoral head of early stake,were treated with minimally invasive decompression, bone graft implantation and metal trabecular bone reconstruction system, including 31 males (40 hips), 19 females (22 hip) with an average age of 36.2 years old ranging from 22 to 54 years old. The course of disease was from 6 to 15 months (averaged 10.5 months). Among them, 19 cases (23 hips) were steroid-induced, 25 cases (33 hips) were alcohol-induced, 6 cases (6 hips) were idiopathic; According to ARCO stage, 28 hips were at stage I, 34 hips were at stage II. All of them were diagnosed as femoral head necrosis by imaging examination before operation. Then each patient was followed to assess by Harris hip score, curative effect, and conduct the femoral head survival analysis during the postoperation. All patients had finished operation, the operation time was between 30 and 85 min, intraoperative blood loss was 50 to 220 ml, and 47 cases (58 hips) were follow-up from 24 to 46 months with an average of 34.05 months. As compared with preoperative, the Harris hip score at the last follow-up was improved, the difference was statistically significant (Pfemoral head in ARCO stage I was superior to these in ARCO Stage II, the difference was statistically significant (Posteonecrosis of femoral head was good,it could significantly improve the Harris hip score, increase the femoral head survival time, delay the hip replacement, and performance better in ARCO stage I.

  19. Application of FT-IR microspectroscopy to the study of an injectable composite for bone and dental surgery.

    OpenAIRE

    Weiss, Pierre; Bohic, Sylvain; Lapkowski, Mieczyslaw; Daculsi, Guy

    1998-01-01

    Hydroxypropylmethylcellulose (HPMC) of high-viscosity grade is used as a ligand for a bioactive calcium phosphate ceramic (the filler) in a ready-to-use injectable sterilized biomaterial for bone and dental surgery. Application of physico-chemical methods such as XPS, NMR, or Raman spectroscopy encounters difficulties when used to study such a multiphased material. This paper reports on the application of FT-IR microspectroscopy (FT-IRM) for the investigation of inorganic and organic phases o...

  20. Differential response of bone and kidney to ACEI in db/db mice: A potential effect of captopril on accelerating bone loss.

    Science.gov (United States)

    Zhang, Yan; Li, Xiao-Li; Sha, Nan-Nan; Shu, Bing; Zhao, Yong-Jian; Wang, Xin-Luan; Xiao, Hui-Hui; Shi, Qi; Wong, Man-Sau; Wang, Yong-Jun

    2017-04-01

    The components of renin-angiotensin system (RAS) are expressed in the kidney and bone. Kidney disease and bone injury are common complications associated with diabetes. This study aimed to investigate the effects of an angiotensin-converting enzyme inhibitor, captopril, on the kidney and bone of db/db mice. The db/db mice were orally administered by gavage with captopril for 8weeks with db/+ mice as the non-diabetic control. Serum and urine biochemistries were determined by standard colorimetric methods or ELISA. Histological measurements were performed on the kidney by periodic acid-schiff staining and on the tibial proximal metaphysis by safranin O and masson-trichrome staining. Trabecular bone mass and bone quality were analyzed by microcomputed tomography. Quantitative polymerase chain reaction and immunoblotting were applied for molecular analysis on mRNA and protein expression. Captopril significantly improved albuminuria and glomerulosclerosis in db/db mice, and these effects might be attributed to the down-regulation of angiotensin II expression and the expression of its down-stream profibrotic factors in the kidney, like connective tissue growth factor and vascular endothelial growth factor. Urinary excretion of calcium and phosphorus markedly increased in db/db mice in response to captopril. Treatment with captopril induced a decrease in bone mineral density and deterioration of trabecular bone at proximal metaphysis of tibia in db/db mice, as shown in the histological and reconstructed 3-dimensional images. Even though captopril effectively reversed the diabetes-induced changes in calcium-binding protein 28-k and vitamin D receptor expression in the kidney as well as the expression of RAS components and bradykinin receptor-2 in bone tissue, treatment with captopril increased the osteoclast-covered bone surface, reduced the osteoblast-covered bone surface, down-regulated the expression of type 1 collagen and transcription factor runt-related transcription

  1. Electric field as a potential directional cue in homing of bone marrow-derived mesenchymal stem cells to cutaneous wounds.

    Science.gov (United States)

    Zimolag, Eliza; Borowczyk-Michalowska, Julia; Kedracka-Krok, Sylwia; Skupien-Rabian, Bozena; Karnas, Elzbieta; Lasota, Slawomir; Sroka, Jolanta; Drukala, Justyna; Madeja, Zbigniew

    2017-02-01

    Bone marrow-derived cells are thought to participate and enhance the healing process contributing to skin cells or releasing regulatory cytokines. Directional cell migration in a weak direct current electric field (DC-EF), known as electrotaxis, may be a way of cell recruitment to the wound site. Here we examined the influence of electric field on bone marrow adherent cells (BMACs) and its potential role as a factor attracting mesenchymal stem cells to cutaneous wounds. We observed that in an external EF, BMAC movement was accelerated and highly directed with distinction of two cell populations migrating toward opposite poles: mesenchymal stem cells migrated toward the cathode, whereas macrophages toward the anode. Analysis of intracellular pathways revealed that macrophage electrotaxis mostly depended on Rho family small GTPases and calcium ions, but interruption of PI3K and Arp2/3 had the most pronounced effect on electrotaxis of MSCs. However, in all cases we observed only a partial decrease in directionality of cell movement after inhibition of certain proteins. Additionally, although we noticed the accumulation of EGFR at the cathodal side of MSCs, it was not involved in electrotaxis. Moreover, the cell reaction to EF was very dynamic with first symptoms occurring within <1min. In conclusion, the physiological DC-EF may act as a factor positioning bone marrow cells within a wound bed and the opposite direction of MSC and macrophage movement did not result either from utilizing different signalling or redistribution of investigated cell surface receptors. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Strontium-89 for prostate cancer with bone metastases. The potential of cancer control and improvement of overall survival

    International Nuclear Information System (INIS)

    Kuroda, Isao

    2014-01-01

    Strontium-89 (Sr-89) has been considered to have a tumoricidal effect with minimal adverse events. However, few reports have investigated these effects in detail. In this study, we examined the tumoricidal and pain-relief effects of Sr-89 on prostate cancer with bone metastasis as well as survival. A retrospective study was performed involving 31 prostate cancer patients with bone metastasis treated with Sr-89. Using prostate specific antigen (PSA) as an evaluation criterion of cancer control, patients were divided into PSA responder and non-responder groups, and the survival rates of these groups were compared. In addition, using the total amount of painkillers administered as an evaluation criterion of pain relief, patients were divided into pain responder and non-responder groups, and the survival rates of these groups were also compared. As secondary investigation items, age, PSA (ng/ml), pain site, extent of the disease, the presence or absence of castration-resistant prostatic cancer (CRPC), the presence or absence of a past medical history of treatment with docetaxel in CRPC cases, Gleason Score, hemoglobin (g/dl), platelet (Plt) (/μl), serum carboxyterminal telopeptide of type I collagen (ng/ml), and bone-alkaline phosphatase (BAP) (U/l) were investigated. Longer survival was expected for the PSA responder group than for the PSA non-responder group, and whether the spine was the pain site and the presence or absence of CRPC were useful as predictors of this. Plt was suggested to be a useful indicator. Furthermore, the survival time was significantly longer in the pain responder group than in the pain non-responder group, and whether the pain site was present in the spine was considered to be a predictor; however, no significant difference was noted in any of the items assumed to be biomarkers. Sr-89 has the potential to control PSA and prolong survival. A large-scale prospective study of the therapeutic effect of Sr-89 is expected. (author)

  3. Mobilization of endogenous bone marrow derived endothelial progenitor cells and therapeutic potential of parathyroid hormone after ischemic stroke in mice.

    Directory of Open Access Journals (Sweden)

    Li-Li Wang

    Full Text Available Stroke is a major neurovascular disorder threatening human life and health. Very limited clinical treatments are currently available for stroke patients. Stem cell transplantation has shown promising potential as a regenerative treatment after ischemic stroke. The present investigation explores a new concept of mobilizing endogenous stem cells/progenitor cells from the bone marrow using a parathyroid hormone (PTH therapy after ischemic stroke in adult mice. PTH 1-34 (80 µg/kg, i.p. was administered 1 hour after focal ischemia and then daily for 6 consecutive days. After 6 days of PTH treatment, there was a significant increase in bone marrow derived CD-34/Fetal liver kinase-1 (Flk-1 positive endothelial progenitor cells (EPCs in the peripheral blood. PTH treatment significantly increased the expression of trophic/regenerative factors including VEGF, SDF-1, BDNF and Tie-1 in the brain peri-infarct region. Angiogenesis, assessed by co-labeled Glut-1 and BrdU vessels, was significantly increased in PTH-treated ischemic brain compared to vehicle controls. PTH treatment also promoted neuroblast migration from the subventricular zone (SVZ and increased the number of newly formed neurons in the peri-infarct cortex. PTH-treated mice showed significantly better sensorimotor functional recovery compared to stroke controls. Our data suggests that PTH therapy improves endogenous repair mechanisms after ischemic stroke with functional benefits. Mobilizing endogenous bone marrow-derived stem cells/progenitor cells using PTH and other mobilizers appears an effective and feasible regenerative treatment after ischemic stroke.

  4. Applications of Fluorine-18 in Biological Studies with Special Reference to Bone and Thyroid Physiology

    International Nuclear Information System (INIS)

    Anbar, M.

    1963-01-01

    diminish the overall iodine uptake. Next, it was demonstrated that the trapping stage is much less radiosensitive than the stages of thyroxine formation and release. A quite different application of F 16 -labelled fluoroborate ions was in the localization of brain tumours, by directional coincidence scanning owing to the limited permeability of these ions via the intact blood- brain barrier. Fluorine-18 labelled fluoraromatic chelating agents were prepared and applied to problems in bone physiology. Fluorine-18 labelled aromatic vital dyes were used in investigating problems of permeability through biological membranes. Fluorine-18 labelled fluorine containing antimetabolites including 5-fluorouracyl and fluoro-orotic acid, have been prepared and applied to physiological problems, including cancer research. (author) [fr

  5. Bioactive Glass Fiber Reinforced Starch-Polycaprolactone Composite for Bone Applications

    International Nuclear Information System (INIS)

    Jukola, H.; Nikkola, L.; Tukiainen, M.; Kellomaeki, M.; Ashammakhi, N.; Gomes, M. E.; Reis, R. L.; Chiellini, F.; Chiellini, E.

    2008-01-01

    For bone regeneration and repair, combinations of different materials are often needed. Biodegradable polymers are often combined with osteoconductive materials, such as bioactive glass (BaG), which can also improve the mechanical properties of the composite. The aim of this study was to develop and characterize BaG fiber-reinforced starch-poly-ε-caprolactone (SPCL) composite. Sheets of SPCL (30/70 wt%) were produced using single-screw extrusion. They were then cut and compression molded in layers with BaG fibers to form composite structures of different combinations. Thermal, mechanical, and degradation properties of the composites were studied. The actual amount of BaG in the composites was determined using combustion tests. A strong endothermic peak indicating melting at about 56 deg. C was observed by differential scanning calorimetry (DSC) analysis. Thermal gravimetry analysis (TGA) showed that thermal decomposition of SPCL started at 325 deg. C with the decomposition of starch and continued at 400 deg. C with the degradation of polycaprolactone (PCL). Initial mechanical properties of the reinforced composites were at least 50% better than the properties of the non-reinforced composites. However, the mechanical properties of the composites after two weeks of hydrolysis were comparable to those of the non-reinforced samples. During the six weeks' hydrolysis the mass of the composites had decreased only by about 5%. The amount of glass in the composites remained the same for the six-week period of hydrolysis. In conclusion, it is possible to enhance the initial mechanical properties of SPCL by reinforcing it with BaG fibers. However, the mechanical properties of the composites are only sufficient for use as filler material and they need to be further improved to allow long-lasting bone applications

  6. Bioactive Glass Fiber Reinforced Starch-Polycaprolactone Composite for Bone Applications

    Science.gov (United States)

    Jukola, H.; Nikkola, L.; Gomes, M. E.; Chiellini, F.; Tukiainen, M.; Kellomäki, M.; Chiellini, E.; Reis, R. L.; Ashammakhi, N.

    2008-02-01

    For bone regeneration and repair, combinations of different materials are often needed. Biodegradable polymers are often combined with osteoconductive materials, such as bioactive glass (BaG), which can also improve the mechanical properties of the composite. The aim of this study was to develop and characterize BaG fiber-reinforced starch-poly-ɛ-caprolactone (SPCL) composite. Sheets of SPCL (30/70 wt%) were produced using single-screw extrusion. They were then cut and compression molded in layers with BaG fibers to form composite structures of different combinations. Thermal, mechanical, and degradation properties of the composites were studied. The actual amount of BaG in the composites was determined using combustion tests. A strong endothermic peak indicating melting at about 56 °C was observed by differential scanning calorimetry (DSC) analysis. Thermal gravimetry analysis (TGA) showed that thermal decomposition of SPCL started at 325 °C with the decomposition of starch and continued at 400 °C with the degradation of polycaprolactone (PCL). Initial mechanical properties of the reinforced composites were at least 50% better than the properties of the non-reinforced composites. However, the mechanical properties of the composites after two weeks of hydrolysis were comparable to those of the non-reinforced samples. During the six weeks' hydrolysis the mass of the composites had decreased only by about 5%. The amount of glass in the composites remained the same for the six-week period of hydrolysis. In conclusion, it is possible to enhance the initial mechanical properties of SPCL by reinforcing it with BaG fibers. However, the mechanical properties of the composites are only sufficient for use as filler material and they need to be further improved to allow long-lasting bone applications.

  7. Nanotechnology in meat processing and packaging: potential applications - a review.

    Science.gov (United States)

    Ramachandraiah, Karna; Han, Sung Gu; Chin, Koo Bok

    2015-02-01

    Growing demand for sustainable production, increasing competition and consideration of health concerns have led the meat industries on a path to innovation. Meat industries across the world are focusing on the development of novel meat products and processes to meet consumer demand. Hence, a process innovation, like nanotechnology, can have a significant impact on the meat processing industry through the development of not only novel functional meat products, but also novel packaging for the products. The potential benefits of utilizing nanomaterials in food are improved bioavailability, antimicrobial effects, enhanced sensory acceptance and targeted delivery of bioactive compounds. However, challenges exist in the application of nanomaterials due to knowledge gaps in the production of ingredients such as nanopowders, stability of delivery systems in meat products and health risks caused by the same properties which also offer the benefits. For the success of nanotechnology in meat products, challenges in public acceptance, economics and the regulation of food processed with nanomaterials which may have the potential to persist, accumulate and lead to toxicity need to be addressed. So far, the most promising area for nanotechnology application seems to be in meat packaging, but the long term effects on human health and environment due to migration of the nanomaterials from the packaging needs to be studied further. The future of nanotechnology in meat products depends on the roles played by governments, regulatory agencies and manufacturers in addressing the challenges related to the application of nanomaterials in food.

  8. Thermophotovoltaic potential applications for civilian and industrial use in Japan

    Science.gov (United States)

    Yamaguchi, Hiromi; Yamaguchi, Masafumi

    1999-03-01

    Investigative research on potential market for TPV power sources in Japan has been focused on how TPV can contribute to energy conservation and environmental protection and harmony. The application needs for TPV were surveyed in comparison with conventional engine or turbine generators and developing power generation technologies such as fuel cells or chemical batteries, etc. The investigation on the performance of commercial generators shows that regarding system efficiency, TPV can compete with conventional generators in the output power class of tens of kW. According to the sales for small scale generators in Japan, most of the generators below 10 kW class are utilized mainly for construction, communication, leisure, and that 10-100 kW class generators are for cogeneration in small buildings. Waste heat recovery in dispersed furnaces is another potential application of compact TPV cells. Exhaust heat from small scale incinerators and industrial furnaces is undesirable to be recorded into electricity due to excessive heat loss of the smaller steam turbine generators. Solar powered TPV is also of our concern as a natural energy use. From the viewpoint of applicability for TPV, portable generators cogeneration systems, and solar power plants were selected for our system consideration. Intermediate report on the feasibility study concerning such TPV systems is given as well as the review of the current status of competing power generation technologies in Japan.

  9. Minor snake venom proteins: Structure, function and potential applications.

    Science.gov (United States)

    Boldrini-França, Johara; Cologna, Camila Takeno; Pucca, Manuela Berto; Bordon, Karla de Castro Figueiredo; Amorim, Fernanda Gobbi; Anjolette, Fernando Antonio Pino; Cordeiro, Francielle Almeida; Wiezel, Gisele Adriano; Cerni, Felipe Augusto; Pinheiro-Junior, Ernesto Lopes; Shibao, Priscila Yumi Tanaka; Ferreira, Isabela Gobbo; de Oliveira, Isadora Sousa; Cardoso, Iara Aimê; Arantes, Eliane Candiani

    2017-04-01

    Snake venoms present a great diversity of pharmacologically active compounds that may be applied as research and biotechnological tools, as well as in drug development and diagnostic tests for certain diseases. The most abundant toxins have been extensively studied in the last decades and some of them have already been used for different purposes. Nevertheless, most of the minor snake venom protein classes remain poorly explored, even presenting potential application in diverse areas. The main difficulty in studying these proteins lies on the impossibility of obtaining sufficient amounts of them for a comprehensive investigation. The advent of more sensitive techniques in the last few years allowed the discovery of new venom components and the in-depth study of some already known minor proteins. This review summarizes information regarding some structural and functional aspects of low abundant snake venom proteins classes, such as growth factors, hyaluronidases, cysteine-rich secretory proteins, nucleases and nucleotidases, cobra venom factors, vespryns, protease inhibitors, antimicrobial peptides, among others. Some potential applications of these molecules are discussed herein in order to encourage researchers to explore the full venom repertoire and to discover new molecules or applications for the already known venom components. Copyright © 2016. Published by Elsevier B.V.

  10. A comparative analysis of scaffold material modifications for load-bearing applications in bone tissue engineering.

    Science.gov (United States)

    Chim, H; Hutmacher, D W; Chou, A M; Oliveira, A L; Reis, R L; Lim, T C; Schantz, J-T

    2006-10-01

    To facilitate optimal application of appropriate scaffold architectures for clinical trials, there is a need to compare different scaffold modifications under similar experimental conditions. In this study was assessed the effectiveness of poly-e-caprolactone (PCL) scaffolds fabricated by fused deposition modelling (FDM), with varying material modifications, for the purposes of bone tissue engineering. The incorporation of hydroxyapatite (HA) in PCL scaffolds, as well as precalcification through immersion in a simulated body fluid (SBF) to produce a biomimetic apatite coating on the scaffolds, was assessed. A series of in vitro studies spanning 3 weeks as well as in vivo studies utilizing a subcutaneous nude mouse model were carried out. PCL and HA-PCL scaffolds demonstrated increasing tissue growth extending throughout the implants, as well as superior mechanical strength and mineralization, as evidenced by X-ray imaging after 14 weeks in vivo. No significant difference was found between PCL and HA-PCL scaffolds. Precalcification with SBF did not result in increased osteoconductivity and cell proliferation as previously reported. Conversely, tensile forces exerted by tissue sheets bridging adjacent struts of the PCL scaffold caused flaking of the apatite coating that resulted in impaired cell attachment, growth and mineralization. The results suggest that scaffolds fabricated by FDM may have load-bearing applications.

  11. Effect of hyaluronic acid in bone formation and its applications in dentistry.

    Science.gov (United States)

    Zhao, Ningbo; Wang, Xin; Qin, Lei; Zhai, Min; Yuan, Jing; Chen, Ji; Li, Dehua

    2016-06-01

    Hyaluronic acid (HA), the simplest glycosaminoglycan, participates in several important biological procedures, including mediation of cellular signaling, regulation of cell adhesion and proliferation, and manipulation of cell differentiation. The effect of HA on cell proliferation and differentiation depends on its molecular weight (MW) and concentration. Moreover, the properties of high viscosity, elasticity, highly negative charge, biocompatibility, biodegradability, and nonimmunogenicity make HA attractive in tissue engineering and disease treatment. This review comprises an overview of the effect of HA on cell proliferation and differentiation in vitro, the role of HA in bone regeneration in vivo, and the clinical applications of HA in dentistry, focusing on the mechanism underlining the effect of MW and concentration of HA on cell proliferation and osteogenic differentiation. It is expected that practical progress of HA both in laboratory-based experiments and clinical applications will be achieved in the next few years. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1560-1569, 2016. © 2016 Wiley Periodicals, Inc.

  12. Histological evaluation of the influence of magnetic field application in autogenous bone grafts in rats

    Directory of Open Access Journals (Sweden)

    Ponzoni Deise

    2009-01-01

    Full Text Available Abstract Background Bone grafts are widely used in oral and maxillofacial reconstruction. The influence of electromagnetic fields and magnets on the endogenous stimulation of target tissues has been investigated. This work aimed to assess the quality of bone healing in surgical cavities filled with autogenous bone grafts, under the influence of a permanent magnetic field produced by in vivo buried devices. Methods Metal devices consisting of commercially pure martensitic stainless steel washers and titanium screws were employed. Thirty male Wistar rats were divided into 3 experimental and 3 control groups. A surgical bone cavity was produced on the right femur, and a bone graft was collected and placed in each hole. Two metallic washers, magnetized in the experimental group but not in the control group, were attached on the borders of the cavity. Results The animals were sacrificed on postoperative days 15, 45 and 60. The histological analysis of control and experimental samples showed adequate integration of the bone grafts, with intense bone neoformation. On days 45 and 60, a continued influence of the magnetic field on the surgical cavity and on the bone graft was observed in samples from the experimental group. Conclusion The results showed intense bone neoformation in the experimental group as compared to control animals. The intense extra-cortical bone neoformation observed suggests that the osteoconductor condition of the graft may be more susceptible to stimulation, when submitted to a magnetic field.

  13. Stem cells applications in bone and tooth repair and regeneration: New insights, tools, and hopes.

    Science.gov (United States)

    Abdel Meguid, Eiman; Ke, Yuehai; Ji, Junfeng; El-Hashash, Ahmed H K

    2018-03-01

    The exploration of stem and progenitor cells holds promise for advancing our understanding of the biology of tissue repair and regeneration mechanisms after injury. This will also help in the future use of stem cell therapy for the development of regenerative medicine approaches for the treatment of different tissue-species defects or disorders such as bone, cartilages, and tooth defects or disorders. Bone is a specialized connective tissue, with mineralized extracellular components that provide bones with both strength and rigidity, and thus enable bones to function in body mechanical supports and necessary locomotion process. New insights have been added to the use of different types of stem cells in bone and tooth defects over the last few years. In this concise review, we briefly describe bone structure as well as summarize recent research progress and accumulated information regarding the osteogenic differentiation of stem cells, as well as stem cell contributions to bone repair/regeneration, bone defects or disorders, and both restoration and regeneration of bones and cartilages. We also discuss advances in the osteogenic differentiation and bone regeneration of dental and periodontal stem cells as well as in stem cell contributions to dentine regeneration and tooth engineering. © 2017 Wiley Periodicals, Inc.

  14. Adaptive coded aperture imaging: progress and potential future applications

    Science.gov (United States)

    Gottesman, Stephen R.; Isser, Abraham; Gigioli, George W., Jr.

    2011-09-01

    Interest in Adaptive Coded Aperture Imaging (ACAI) continues to grow as the optical and systems engineering community becomes increasingly aware of ACAI's potential benefits in the design and performance of both imaging and non-imaging systems , such as good angular resolution (IFOV), wide distortion-free field of view (FOV), excellent image quality, and light weight construct. In this presentation we first review the accomplishments made over the past five years, then expand on previously published work to show how replacement of conventional imaging optics with coded apertures can lead to a reduction in system size and weight. We also present a trade space analysis of key design parameters of coded apertures and review potential applications as replacement for traditional imaging optics. Results will be presented, based on last year's work of our investigation into the trade space of IFOV, resolution, effective focal length, and wavelength of incident radiation for coded aperture architectures. Finally we discuss the potential application of coded apertures for replacing objective lenses of night vision goggles (NVGs).

  15. Potential biodefense model applications for portable chlorine dioxide gas production.

    Science.gov (United States)

    Stubblefield, Jeannie M; Newsome, Anthony L

    2015-01-01

    Development of decontamination methods and strategies to address potential infectious disease outbreaks and bioterrorism events are pertinent to this nation's biodefense strategies and general biosecurity. Chlorine dioxide (ClO2) gas has a history of use as a decontamination agent in response to an act of bioterrorism. However, the more widespread use of ClO2 gas to meet current and unforeseen decontamination needs has been hampered because the gas is too unstable for shipment and must be prepared at the application site. Newer technology allows for easy, onsite gas generation without the need for dedicated equipment, electricity, water, or personnel with advanced training. In a laboratory model system, 2 unique applications (personal protective equipment [PPE] and animal skin) were investigated in the context of potential development of decontamination protocols. Such protocols could serve to reduce human exposure to bacteria in a decontamination response effort. Chlorine dioxide gas was capable of reducing (2-7 logs of vegetative and spore-forming bacteria), and in some instances eliminating, culturable bacteria from difficult to clean areas on PPE facepieces. The gas was effective in eliminating naturally occurring bacteria on animal skin and also on skin inoculated with Bacillus spores. The culturable bacteria, including Bacillus spores, were eliminated in a time- and dose-dependent manner. Results of these studies suggested portable, easily used ClO2 gas generation systems have excellent potential for protocol development to contribute to biodefense strategies and decontamination responses to infectious disease outbreaks or other biothreat events.

  16. Recent Advances in Biosensor Technology for Potential Applications - An Overview.

    Science.gov (United States)

    Vigneshvar, S; Sudhakumari, C C; Senthilkumaran, Balasubramanian; Prakash, Hridayesh

    2016-01-01

    Imperative utilization of biosensors has acquired paramount importance in the field of drug discovery, biomedicine, food safety standards, defense, security, and environmental monitoring. This has led to the invention of precise and powerful analytical tools using biological sensing element as biosensor. Glucometers utilizing the strategy of electrochemical detection of oxygen or hydrogen peroxide using immobilized glucose oxidase electrode seeded the discovery of biosensors. Recent advances in biological techniques and instrumentation involving fluorescence tag to nanomaterials have increased the sensitive limit of biosensors. Use of aptamers or nucleotides, affibodies, peptide arrays, and molecule imprinted polymers provide tools to develop innovative biosensors over classical methods. Integrated approaches provided a better perspective for developing specific and sensitive biosensors with high regenerative potentials. Various biosensors ranging from nanomaterials, polymers to microbes have wider potential applications. It is quite important to integrate multifaceted approaches to design biosensors that have the potential for diverse usage. In light of this, this review provides an overview of different types of biosensors being used ranging from electrochemical, fluorescence tagged, nanomaterials, silica or quartz, and microbes for various biomedical and environmental applications with future outlook of biosensor technology.

  17. Recent advances in biosensor technology for potential applications - An overview

    Directory of Open Access Journals (Sweden)

    vigneshvar es

    2016-02-01

    Full Text Available Imperative utilization of biosensors has acquired paramount importance in the field of drug discovery, biomedicine, food safety standards, defence, security and environmental monitoring. This has led to the invention of precise and powerful analytical tools using biological sensing element as biosensor. Glucometers utilizing the strategy of electrochemical detection of oxygen or hydrogen peroxide using immobilized glucose oxidase electrode seeded the discovery of biosensors. Recent advances in biological techniques and instrumentation involving fluorescence tag to nanomaterials have increased the sensitive limit of biosensors. Use of aptamers or nucleotides, affibodies, peptide arrays and molecule imprinted polymers provide tools to develop innovative biosensors over classical methods. Integrated approaches provided a better perspective for developing specific and sensitive biosensors with high regenerative potentials. Variety of biosensors ranging from nanomaterials, polymers to microbes have wider potential applications. It is quite important to integrate multifaceted approaches to design biosensors that have the potential for diverse usage. In light of this, this review provides an overview of different types of biosensors being used ranging from electrochemical, fluorescence tagged, nanomaterials, silica or quartz and microbes for various biomedical and environmental applications with future outlook of biosensor technology.

  18. Cancer stemness and metastatic potential of the novel tumor cell line K3: an inner mutated cell of bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Qian, Hui; Ding, Xiaoqing; Zhang, Jiao; Mao, Fei; Sun, Zixuan; Jia, Haoyuan; Yin, Lei; Wang, Mei; Zhang, Xu; Zhang, Bin; Yan, Yongmin; Zhu, Wei; Xu, Wenrong

    2017-06-13

    Mesenchymal stem cells (MSCs) transplantation has been used for therapeutic applications in various diseases. Here we report MSCs can malignantly transform in vivo. The novel neoplasm was found on the tail of female rat after injection with male rat bone marrow-derived MSCs (rBM-MSCs) and the new tumor cell line, K3, was isolated from the neoplasm. The K3 cells expressed surface antigens and pluripotent genes similar to those of rBM-MSCs and presented tumor cell features. Moreover, the K3 cells contained side population cells (SP) like cancer stem cells (CSCs), which might contribute to K3 heterogeneity and tumorigenic capacity. To investigate the metastatic potential of K3 cells, we established the nude mouse models of liver and lung metastases and isolated the corresponding metastatic cell lines K3-F4 and K3-B6. Both K3-F4 and K3-B6 cell lines with higher metastatic potential acquired more mesenchymal and stemness-related features. Epithelial-mesenchymal transition is a potential mechanism of K3-F4 and K3-B6 formation.

  19. The potential of diffraction grating for spatial applications

    Science.gov (United States)

    Jourlin, Y.; Parriaux, O.; Pigeon, F.; Tischenko, A. V.

    2017-11-01

    Diffraction gratings are know, and have been fabricated for more than one century. They are now making a come back for two reasons: first, because they are now better understood which leads to the efficient exploitation of what was then called their "anomalies"; secondly, because they are now fabricable by means of the modern manufacturing potential of planar technologies. Novel grating can now perform better than conventional gratings, and address new application fields which were not expected to be theirs. This is the case of spatial applications where they can offer multiple optical functions, low size, low weight and mechanical robustness. The proposed contribution will briefly discuss the use of gratings for spatial applications. One of the most important applications is in the measurement of displacement. Usual translation and rotation sensors are bulky devices, which impose a system breakdown leading to cumbersome and heavy assemblies. We are proposing a miniaturized version of the traditional moving grating technique using submicron gratings and a specific OptoASIC which enables the measurement function to be non-obtrusively inserted into light and compact electro-mechanical systems. Nanometer resolution is possible with no compromise on the length of the measurement range. Another family of spatial application is in the field of spectrometers where new grating types allow a more flexible processing of the optical spectrum. Another family of applications addresses the question of inter-satellite communications: the introduction of gratings in laser cavities or in the laser mirrors enables the stabilization of the emitted polarization, the stabilization of the frequency as well as wide range frequency sweeping without mobile parts.

  20. FACILE SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL ACTIVITY OF CELLULOSE-CHITOSAN-HYDROXYAPATITE COMPOSITE MATERIAL, A POTENTIAL MATERIAL FOR BONE TISSUE ENGINEERING

    Science.gov (United States)

    Mututuvari, Tamutsiwa M.; Harkins, April L.

    2013-01-01

    Hydroxyapatite (HAp) is often used as a bone-implant material because it is biocompatible and osteoconductive. However, HAp possesses poor rheological properties and it is inactive against disease-causing microbes. To improve these properties, we developed a green method to synthesize multifunctional composites containing: (1) cellulose (CEL) to impart mechanical strength; (2) chitosan (CS) to induce antibacterial activity thereby maintaining a microbe-free wound site; and (3) HAp. In this method, CS and CEL were co-dissolved in an ionic liquid (IL) and then regenerated from water. HAp was subsequently formed in situ by alternately soaking [CEL+CS] composites in aqueous solutions of CaCl2 and Na2HPO4. At least 88% of IL used was recovered for reuse by distilling the aqueous washings of [CEL+CS]. The composites were characterized using FTIR, XRD and SEM. These composites retained the desirable properties of their constituents. For example, the tensile strength of the composites was enhanced 1.9X by increasing CEL loading from 20% to 80%. Incorporating CS in the composites resulted in composites which inhibited the growth of both Gram positive (MRSA, S. aureus and VRE) and Gram negative (E. coli and P. aeruginosa) bacteria. These findings highlight the potential use of [CEL+CS+HAp] composites as scaffolds in bone tissue engineering. PMID:23595871

  1. Potential Bone to Implant Contact Area of Short Versus Standard Implants: An In Vitro Micro-Computed Tomography Analysis.

    Science.gov (United States)

    Quaranta, Alessandro; DʼIsidoro, Orlando; Bambini, Fabrizio; Putignano, Angelo

    2016-02-01

    To compare the available potential bone-implant contact (PBIC) area of standard and short dental implants by micro-computed tomography (μCT) assessment. Three short implants with different diameters (4.5 × 6 mm, 4.1 × 7 mm, and 4.1 × 6 mm) and 2 standard implants (3.5 × 10 mm and 3.3 × 9 mm) with diverse design and surface features were scanned with μCT. Cross-sectional images were obtained. Image data were manually processed to find the plane that corresponds to the most coronal contact point between the crestal bone and implant. The available PBIC was calculated for each sample. Later on, the cross-sectional slices were processed by a 3-dimensional (3D) software, and 3D images of each sample were used for descriptive analysis and display the microtopography and macrotopography. The wide-diameter short implant (4.5 × 6 mm) showed the higher PBIC (210.89 mm) value followed by the standard (178.07 mm and 185.37 mm) and short implants (130.70 mm and 110.70 mm). Wide-diameter short implants show a surface area comparable with standard implants. Micro-CT analysis is a promising technique to evaluate surface area in dental implants with different macrodesign, microdesign, and surface features.

  2. Green synthesis of nanoparticles and its potential application.

    Science.gov (United States)

    Hussain, Imtiyaz; Singh, N B; Singh, Ajey; Singh, Himani; Singh, S C

    2016-04-01

    Nanotechnology is a new and emerging technology with wealth of applications. It involves the synthesis and application of materials having one of the dimensions in the range of 1-100 nm. A wide variety of physico-chemical approaches are being used these days for the synthesis of nanoparticles (NPs). However, biogenic reduction of metal precursors to produce corresponding NPs is eco-friendly, less expensive, free of chemical contaminants for medical and biological applications where purity of NPs is of major concern. Biogenic reduction is a "Bottom Up" approach similar to chemical reduction where a reducing agent is replaced by extract of a natural products with inherent stabilizing, growth terminating and capping properties. Furthermore, the nature of biological entities in different concentrations in combination with reducing organic agents influence the size and shape of NPs. Present review focuses on microbes or plants based green synthesis of Ag, Au, Cu, Fe, Pd, Ru, PbS, CdS, CuO, CeO2, Fe3O4, TiO2, and ZnO NPs and their potential applications.

  3. Epicardial Application Of Laser Energy In Vivo: Acute Arrhythmogenic Potential

    Science.gov (United States)

    Cohen, Mark H.; Ben-Shachar, Giora; Beder, Stanley D.; Sivakoff, Mark; Riemenschneider, Thomas A.

    1986-01-01

    In order to assess the effect of laser energy on the heart's rhythm, 7 newborn pigs each had 3 two-second applications of laser energy directly to the left ventricular epicardial surface. A quartz fiberoptic delivery system was used. All piglets (in all 21 applications) had ventricular arrhythmia induced. This varied from single premature ventricular contractions to sustained(112 seconds) ventricular tachycardia (6/7 piglets). The sustained ventri-cular tachycardia exhibited electrophysiologic criteria of a "re-entrant" mechanism. Fifteen minutes following lasing, programmed ventricular stimulation, a technique that indicates whether a substrate may be present for spontaneous re-entrant arrhythmias, showed induced arrhythmia in only 2/7 pigs, neither sustained. We conclude that epicardial application of laser energy frequently results in significant ventricular arrhythmia. This arrhythmia appears to be re-entrant in nature. Fowever, shortly following lasing, sustained arrhythmia could not be induced. Therefore, we feel that more knowledge about the arrhythmogenic potential of laser lesions is needed prior to wide-spread clinical application.

  4. Bacterial and Fungal Proteolytic Enzymes: Production, Catalysis and Potential Applications.

    Science.gov (United States)

    da Silva, Ronivaldo Rodrigues

    2017-09-01

    Submerged and solid-state bioprocesses have been extensively explored worldwide and employed in a number of important studies dealing with microbial cultivation for the production of enzymes. The development of these production technologies has facilitated the generation of new enzyme-based products with applications in pharmaceuticals, food, bioactive peptides, and basic research studies, among others. The applicability of microorganisms in biotechnology is potentiated because of their various advantages, including large-scale production, short time of cultivation, and ease of handling. Currently, several studies are being conducted to search for new microbial peptidases with peculiar biochemical properties for industrial applications. Bioprospecting, being an important prerequisite for research and biotechnological development, is based on exploring the microbial diversity for enzyme production. Limited information is available on the production of specific proteolytic enzymes from bacterial and fungal species, especially on the subgroups threonine and glutamic peptidases, and the seventh catalytic type, nonhydrolytic asparagine peptide lyase. This gap in information motivated the present study about these unique biocatalysts. In this study, the biochemical and biotechnological aspects of the seven catalytic types of proteolytic enzymes, namely aspartyl, cysteine, serine, metallo, glutamic, and threonine peptidase, and asparagine peptide lyase, are summarized, with an emphasis on new studies, production, catalysis, and application of these enzymes.

  5. 3-Dimensional cell-laden nano-hydroxyapatite/protein hydrogels for bone regeneration applications

    Energy Technology Data Exchange (ETDEWEB)

    Sadat-Shojai, Mehdi, E-mail: msadatshojai@gmail.com [Department of Chemistry, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Department of Biomaterials, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of); Khorasani, Mohammad-Taghi [Department of Biomaterials, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of); Jamshidi, Ahmad [Department of Novel Drug Delivery Systems, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of)

    2015-04-01

    The ability to encapsulate cells in three-dimensional (3D) protein-based hydrogels is potentially of benefit for tissue engineering and regenerative medicine. However, as a result of their poor mechanical strength, protein-based hydrogels have traditionally been considered for soft tissue engineering only. Hence, in this study we tried to render these hydrogels suitable for hard tissue regeneration, simply by incorporation of bioactive nano-hydroxyapatite (HAp) into a photocrosslinkable gelatin hydrogel. Different cell types were also encapsulated in three dimensions in the resulting composites to prepare cell-laden constructs. According to the results, HAp significantly improves the stiffness of gelatin hydrogels, while it maintains their structural integrity and swelling ratio. It was also found that while the bare hydrogel (control) was completely inert in terms of bioactivity, a homogeneous 3D mineralization occurs throughout the nanocomposites after incubation in simulated body fluid. Moreover, encapsulated cells readily elongated, proliferated, and formed a 3D interconnected network with neighboring cells in the nanocomposite, showing the suitability of the nano-HAp/protein hydrogels for cellular growth in 3D. Therefore, the hydrogel nanocomposites developed in this study may be promising candidates for preparing cell-laden tissue-like structures with enhanced stiffness and increased osteoconductivity to induce bone formation in vivo. - Highlights: • We tried to render protein-based hydrogels suitable for hard tissue regeneration. • We developed a three-component system comprising hydrogel, nano-HAp, and cells. • Nano-HAp significantly improved the mechanical strength of hydrogel. • Encapsulated cells readily elongated and proliferated in 3D cell-laden nanocomposite. • 3D deposition of bone crystals occurred in the hydrogel nanocomposites.

  6. Neural networks and their potential application in nuclear power plants

    International Nuclear Information System (INIS)

    Uhrig, R.E.

    1991-01-01

    A neural network is a data processing system consisting of a number of simple, highly interconnected processing elements in an architecture inspired by the structure of the cerebral cortex portion of the brain. Hence, neural networks are often capable of doing things which humans or animals do well but which conventional computers often do poorly. Neural networks have emerged in the past few years as an area of unusual opportunity for research, development and application to a variety of real world problems. Indeed, neural networks exhibit characteristics and capabilities not provided by any other technology. Examples include reading Japanese Kanji characters and human handwriting, reading a typewritten manuscript aloud, compensating for alignment errors in robots, interpreting very noise signals (e.g., electroencephalograms), modeling complex systems that cannot be modeled mathematically, and predicting whether proposed loans will be good or fail. This paper presents a brief tutorial on neural networks and describes research on the potential applications to nuclear power plants

  7. Expert system characteristics and potential applications in safeguards

    International Nuclear Information System (INIS)

    Chapman, L.D.

    1986-01-01

    The general growth of expert, knowledge-based (KB) or rule based systems will significantly increase in the next three to five years. Improvements in computer hardware (speed, reduced size, power) and software (rule based, data based, user interfaces) in recent years are providing the foundations for the growth of expert systems. A byproduct of this growth will undoubtedly be the application of expert systems to various safeguards problems. Characteristics of these expert systems will involve 1) multiple rules governing an outcome, 2) confidence factors on individual variables and rule sets, 3) priority, cost, and risk based rule sets, and 4) the reasoning behind the advice or decision given by the expert system. This paper presents characteristics, structures, and examples of simple rule based systems. Potential application areas for these expert systems may include training, operations, management, designs, evaluations, and specific hardware operation

  8. Electric Potential and Electric Field Imaging with Dynamic Applications & Extensions

    Science.gov (United States)

    Generazio, Ed

    2017-01-01

    The technology and methods for remote quantitative imaging of electrostatic potentials and electrostatic fields in and around objects and in free space is presented. Electric field imaging (EFI) technology may be applied to characterize intrinsic or existing electric potentials and electric fields, or an externally generated electrostatic field made be used for volumes to be inspected with EFI. The baseline sensor technology (e-Sensor) and its construction, optional electric field generation (quasi-static generator), and current e- Sensor enhancements (ephemeral e-Sensor) are discussed. Critical design elements of current linear and real-time two-dimensional (2D) measurement systems are highlighted, and the development of a three dimensional (3D) EFI system is presented. Demonstrations for structural, electronic, human, and memory applications are shown. Recent work demonstrates that phonons may be used to create and annihilate electric dipoles within structures. Phonon induced dipoles are ephemeral and their polarization, strength, and location may be quantitatively characterized by EFI providing a new subsurface Phonon-EFI imaging technology. Results from real-time imaging of combustion and ion flow, and their measurement complications, will be discussed. Extensions to environment, Space and subterranean applications will be presented, and initial results for quantitative characterizing material properties are shown. A wearable EFI system has been developed by using fundamental EFI concepts. These new EFI capabilities are demonstrated to characterize electric charge distribution creating a new field of study embracing areas of interest including electrostatic discharge (ESD) mitigation, manufacturing quality control, crime scene forensics, design and materials selection for advanced sensors, combustion science, on-orbit space potential, container inspection, remote characterization of electronic circuits and level of activation, dielectric morphology of

  9. HTR process heat applications, status of technology and economical potential

    International Nuclear Information System (INIS)

    Barnet, H.

    1997-01-01

    The technical and industrial feasibility of the production of high temperature heat from nuclear fuel is presented. The technical feasibility of high temperature heat consuming processes is reviewed and assessed. The conclusion is drawn that the next technological step for pilot plant scale demonstration is the nuclear heated steam reforming process. The economical potential of HTR process heat applications is reviewed: It is directly coupled to the economical competitiveness of HTR electricity production. Recently made statements and pre-conditions on the economic competitiveness in comparison to world market coal are reported. (author). 8 figs

  10. Potential applications of microbial surfactants in biomedical sciences.

    Science.gov (United States)

    Singh, Pooja; Cameotra, Swaranjit Singh

    2004-03-01

    The main commercial use of biosurfactants is in pollution remediation because of their ability to stabilize emulsions. This enhances the solubility and availability of hydrophobic pollutants, thus increasing their potential for biodegradation. One useful property of many biosurfactants that has not been reviewed extensively is their antimicrobial activity. Several biosurfactants have strong antibacterial, antifungal and antiviral activity. Other medically relevant uses of biosurfactants include their role as anti-adhesive agents to pathogens, making them useful for treating many diseases and as therapeutic and probiotic agents. Here, we discuss some of the new and exciting applications and related developments of various microbial surfactants in the field of biomedical sciences.

  11. In vitro bioactivity assessment of composite membrane containing antimicrobial lauric acid for guided bone regeneration in dental application

    Science.gov (United States)

    Suleiman, Muhammad Jabir; Kalitheertha, Jamuna Thevi; Sabri, Siti Noorzidah

    2015-07-01

    The manuscript reflect research work in fabrication of a triple layered composite membrane and to perform an in vitro bioactivity evaluation on composite membrane containing antimicrobial lauric acid. Poly(lactic-co-glycolic acid) (PLGA) matrix was incorporated with various amounts of nanoapatite (NAp) and lauric acid (LA) to form a triple-layered composite membrane. This membrane was prepared using a single step fabrication technique comprising of solvent casting, thermally induced phase separation and solvent leaching processes. Apatite mineralization was detected on the composite membranes within 30 days of exposure to simulated body fluid (SBF) and showed increased apatite formation at 30-60wt% of NAp content in the PLGA matrix on layer 3 (L3), that has the highest amount of NAp compared with layer 1 (L1) and layer 2 (L2) of the membrane. However, apatite mineralization was not detected on pure PLGA membrane. In addition, incorporation of LA on L1 and L2 has no influence on apatite mineral formation as none detected on these surfaces. The presence of NAp determines the formation of apatite crystals on the composite membrane. These membranes with triple layered design and bioactive properties showed potential use for guided bone regeneration purposes in dental application.

  12. Stem cells in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Jeong Min [Department of Preventive and Social Dentistry and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Mantalaris, Anathathios, E-mail: yshwang@khu.ac.k [Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom)

    2010-12-15

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  13. Stem cells in bone tissue engineering

    International Nuclear Information System (INIS)

    Seong, Jeong Min; Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik; Mantalaris, Anathathios

    2010-01-01

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  14. Dental pulp stem cells immobilized in alginate microspheres for applications in bone tissue engineering.

    Science.gov (United States)

    Kanafi, M M; Ramesh, A; Gupta, P K; Bhonde, R R

    2014-07-01

    To immobilize dental pulp stem cells (DPSC) in alginate microspheres and to determine cell viability, proliferation, stem cell characteristics and osteogenic potential of the immobilized DPSCs. Human DPSCs isolated from the dental pulp were immobilized in 1% w/v alginate microspheres. Viability and proliferation of immobilized DPSCs were determined by trypan blue and MTT assay, respectively. Stem cell characteristics of DPSCs post immobilization were verified by labelling the cells with CD73 and CD90. Osteogenic potential of immobilized DPSCs was assessed by the presence of osteocalcin. Alizarin red staining and O-cresolphthalein complexone method confirmed and quantified calcium deposition. A final reverse transcriptase PCR evaluated the expression of osteogenic markers - ALP, Runx-2 and OCN. More than 80% of immobilized DPSCs were viable throughout the 3-week study. Proliferation appeared controlled and consistent unlike DPSCs in the control group. Presence of CD73 and CD90 markers confirmed the stem cell nature of immobilized DPSCs. The presence of osteocalcin, an osteoblastic marker, was confirmed in the microspheres on day 21. Mineralization assays showed high calcium deposition indicating elevated osteogenic potential of immobilized DPSCs. Osteogenic genes- ALP, Runx-2 and OCN were also upregulated in immobilized DPSCs. Surprisingly, immobilized DPSCs in the control group cultured in conventional stem cell media showed upregulation of osteogenic genes and expressed osteocalcin. Dental pulp stem cells immobilized in alginate hydrogels exhibit enhanced osteogenic potential while maintaining high cell viability both of which are fundamental for bone tissue regeneration. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  15. Extracellular polymeric substances of bacteria and their potential environmental applications.

    Science.gov (United States)

    More, T T; Yadav, J S S; Yan, S; Tyagi, R D; Surampalli, R Y

    2014-11-01

    Biopolymers are considered a potential alternative to conventional chemical polymers because of their ease of biodegradability, high efficiency, non-toxicity and non-secondary pollution. Recently, extracellular polymeric substances (EPS, biopolymers produced by the microorganisms) have been recognised by many researchers as a potential flocculent for their applications in various water, wastewater and sludge treatment processes. In this context, literature information on EPS is widely dispersed and is very scarce. Thus, this review marginalizes various studies conducted so far about EPS nature-production-recovery, properties, environmental applications and moreover, critically examines future research needs and advanced application prospective of the EPS. One of the most important aspect of chemical composition and structural details of different moieties of EPS in terms of carbohydrates, proteins, extracellular DNA, lipid and surfactants and humic substances are described. These chemical characteristics of EPS in relation to formation and properties of microbial aggregates as well as degradation of EPS in the matrix (biomass, flocs etc) are analyzed. The important engineering properties (based on structural characteristics) such as adsorption, biodegradability, hydrophilicity/hydrophobicity of EPS matrix are also discussed in details. Different aspects of EPS production process such as bacterial strain maintenance; inoculum and factors affecting EPS production were presented. The important factors affecting EPS production include growth phase, carbon and nitrogen sources and their ratio, role of other nutrients (phosphorus, micronutrients/trace elements, and vitamins), impact of pH, temperature, metals, aerobic versus anaerobic conditions and pure and mixed culture. The production of EPS in high concentration with high productivity is essential due to economic reasons. Therefore, the knowledge about all the aspects of EPS production (listed above) is highly

  16. Bone tumor

    Science.gov (United States)

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor; Bone tumor - benign ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  17. Optimized demineralization of human cancellous bone by application of a vacuum.

    Science.gov (United States)

    Eagle, Mark J; Rooney, Paul; Kearney, John N

    2015-07-01

    Human demineralized bone matrix derived from cortical bone is used by surgeons due to its ability to promote bone formation. There is also a need for shaped demineralized bone matrices made from cancellous bone, where the properties of the material allow its insertion into defects, therefore acting as a void filler and scaffold onto which new bone can form. In this study, we report that demineralized bone sponges were prepared by dissecting and cutting knee bone into cancellous bone cubes of 1 cm(3) . These cubes were then taken through a series of warm water washes, some with sonication, centrifugation, and two decontamination chemical washes. The cubes were optimally demineralized into sponges with 0.5N hydrochloric acid under vacuum with constant pH measurement. Demineralization was confirmed by quantitative measurement of calcium and qualitatively by compression. The sponges were freeze dried before terminal sterilisation with a target dose of 25 kGy gamma radiation whilst frozen. Samples of the sponges were histologically examined for calcium and collagen and also tested for osteoinductivity. Data showed well defined collagen staining in the sponges, with little residual calcium. Sponges from two out of three donors demonstrated osteoinductivity when implanted into the muscle of an athymic mouse. © 2014 Wiley Periodicals, Inc.

  18. Clinical uses of radiosterilized freeze-dried human bone: its application in buccomaxillary surgery

    International Nuclear Information System (INIS)

    Wolfsohn, B.; Taramasso, F.; Godoy, J.; Wodowoz, O.; Saldias, M.; Silva, W.; Machin, D.; Sanchez, G.; Alvarez, I.

    2008-01-01

    Full text: The objective of this paper is to evaluate the uses of different human bone tissue allografts in bucomaxillary surgery between 2005 and 2007. Presentation of our experience using single freeze dried bone allografts and associated to bovine collagen membranes (commercial registered). Twenty patients were treated with cortical struts, cancellous chips, morsellized and morsellized demineralized bone. All the grafts were processed at the INDT multi tissue bank from cardiac arrest and brain death cadaveric donors. All the tissues were radiosterilized by Gamma radiation. Bone allografts were used: 1) to optimize bone support increasing maxillar or mandible bone before implant surgery. 2) in dehiscences and fissures during the implant surgery. 3) to stimulate bone regeneration in alveolar cavity, post-apicectomies, and cystectomies as well as for bone defects. The patients were periodically evaluated using standardized protocols. All the cases were successful showing clinic and radiologically osseointegration after 6 and 12 months. Results were evaluated considering surgical technique and patients bucomaxillary rehabilitation. Clinical uses of bone allografts confirm in our experience, as scientific literature outcomes shows, are useful in patients that refuses autografts ablation. (Author)

  19. Motor-Evoked Potential Confirmation of Functional Improvement by Transplanted Bone Marrow Mesenchymal Stem Cell in the Ischemic Rat Brain

    Science.gov (United States)

    Jang, Dong-Kyu; Park, Sang-In; Han, Young-Min; Jang, Kyung-Sool; Park, Moon-Seo; Chung, Young-An; Kim, Min-Wook; Maeng, Lee-So; Huh, Pil-Woo; Yoo, Do-Sung; Jung, Seong-Whan

    2011-01-01

    This study investigated the effect of bone marrow mesenchymal stem cells (BMSCs) on the motor pathway in the transient ischemic rat brain that were transplanted through the carotid artery, measuring motor-evoked potential (MEP) in the four limbs muscle and the atlantooccipital membrane, which was elicited after monopolar and bipolar transcortical stimulation. After monopolar stimulation, the latency of MEP was significantly prolonged, and the amplitude was less reduced in the BMSC group in comparison with the control group (P < .05). MEPs induced by bipolar stimulation in the left forelimb could be measured in 40% of the BMSC group and the I wave that was not detected in the control group was also detected in 40% of the BMSC group. Our preliminary results imply that BMSCs transplanted to the ischemic rat brain mediate effects on the functional recovery of the cerebral motor cortex and the motor pathway. PMID:21772790

  20. Motor-Evoked Potential Confirmation of Functional Improvement by Transplanted Bone Marrow Mesenchymal Stem Cell in the Ischemic Rat Brain

    Directory of Open Access Journals (Sweden)

    Dong-Kyu Jang

    2011-01-01

    Full Text Available This study investigated the effect of bone marrow mesenchymal stem cells (BMSCs on the motor pathway in the transient ischemic rat brain that were transplanted through the carotid artery, measuring motor-evoked potential (MEP in the four limbs muscle and the atlantooccipital membrane, which was elicited after monopolar and bipolar transcortical stimulation. After monopolar stimulation, the latency of MEP was significantly prolonged, and the amplitude was less reduced in the BMSC group in comparison with the control group (<.05. MEPs induced by bipolar stimulation in the left forelimb could be measured in 40% of the BMSC group and the I wave that was not detected in the control group was also detected in 40% of the BMSC group. Our preliminary results imply that BMSCs transplanted to the ischemic rat brain mediate effects on the functional recovery of the cerebral motor cortex and the motor pathway.

  1. Hypoxia-Inducible Factor-1α: A Potential Factor for the Enhancement of Osseointegration between Dental Implants and Tissue-Engineered Bone

    Directory of Open Access Journals (Sweden)

    Duohong Zou

    2011-07-01

    Full Text Available Introduction: Tissue-engineered bones are widely utilized to protect healthy tissue, reduce pain, and increase the success rate of dental implants. one of the most challenging obstacles lies in obtaining effective os-seointegration between dental implants and tissue-engineered structures. Deficiencies in vascularization, osteogenic factors, oxygen, and other nutrients inside the tissue-engineered bone during the early stages following implantation all inhibit effective osseointe-gration. Oxygen is required for aerobic metabolism in bone and blood vessel tissues, but oxygen levels inside tissue-engineered bone are not suf-ficient for cell proliferation. HIF-1α is a pivotal regulator of hypoxic and ischemic vascular responses, driving transcriptional activation of hundreds of genes involved in vascular reactivity, angiogenesis, arteriogenesis, and osteogenesis.The hypothesis: Hypoxia-Inducible Factor-1α seems a potential factor for the enhancement of osseointegration between dental implants and tissue-engineered bone.Evaluation of the hypothesis: Enhancement of HIF-1α protein expression is recognized as the most promising approach for angiogenesis, because it can induce multiple angiogenic targets in a coordinated manner. Therefore, it will be a novel potential therapeutic methods targeting HIF-1α expression to enhance osseointegration be-tween dental implants and tissue-engineered bone.

  2. Electric Potential and Electric Field Imaging with Applications

    Science.gov (United States)

    Generazio, Ed

    2016-01-01

    The technology and techniques for remote quantitative imaging of electrostatic potentials and electrostatic fields in and around objects and in free space is presented. Electric field imaging (EFI) technology may be applied to characterize intrinsic or existing electric potentials and electric fields, or an externally generated electrostatic field may be used for (illuminating) volumes to be inspected with EFI. The baseline sensor technology, electric field sensor (e-sensor), and its construction, optional electric field generation (quasistatic generator), and current e-sensor enhancements (ephemeral e-sensor) are discussed. Demonstrations for structural, electronic, human, and memory applications are shown. This new EFI capability is demonstrated to reveal characterization of electric charge distribution, creating a new field of study that embraces areas of interest including electrostatic discharge mitigation, crime scene forensics, design and materials selection for advanced sensors, dielectric morphology of structures, inspection of containers, inspection for hidden objects, tether integrity, organic molecular memory, and medical diagnostic and treatment efficacy applications such as cardiac polarization wave propagation and electromyography imaging.

  3. The Amniotic Membrane: Development and Potential Applications - A Review.

    Science.gov (United States)

    Favaron, P O; Carvalho, R C; Borghesi, J; Anunciação, A R A; Miglino, M A

    2015-12-01

    Foetal membranes are essential tissues for embryonic development, playing important roles related to protection, breathing, nutrition and excretion. The amnion is the innermost extraembryonic membrane, which surrounds the foetus, forming an amniotic sac that contains the amniotic fluid (AF). In recent years, the amniotic membrane has emerged as a potential tool for clinical applications and has been primarily used in medicine in order to stimulate the healing of skin and corneal diseases. It has also been used in vaginal reconstructive surgery, repair of abdominal hernia, prevention of surgical adhesions and pericardium closure. More recently, it has been used in regenerative medicine because the amniotic-derived stem cells as well as AF-derived cells exhibit cellular plasticity, angiogenic, cytoprotective, immunosuppressive properties, antitumoural potential and the ability to generate induced pluripotent stem cells. These features make them a promising source of stem cells for cell therapy and tissue engineering. In this review, we discussed the development of the amnion, AF and amniotic cavity in different species, as well as the applicability of stem cells from the amnion and AF in cellular therapy. © 2015 Blackwell Verlag GmbH.

  4. Geopolymer Composites for Potential Applications in Cultural Heritage

    Directory of Open Access Journals (Sweden)

    Laura Ricciotti

    2017-12-01

    Full Text Available A new class of geopolymer composites, as materials alternative to traditional binders, was synthesized and its potentialities as restoration material in Cultural Heritage has been explored. This material has been prepared through a co-reticulation reaction in mild conditions of a metakaolin-based geopolymer inorganic matrix and a commercial epoxy resin. The freshly prepared slurry displays a consistency, workability and thixotropic behavior that make it suitable to be spread on different substrates in restoration, repair and reinforcement actions, even on walls and ceilings. Applicability and compatibility tests on tuff and concrete substrates were carried out and the microstructure of the samples in correspondence of the transition zone was analyzed by means of scanning electron microscope (SEM observations and energy dispersive spectroscopy (EDS mapping. Our studies pointed out the formation of a continuous phase between the geopolymer composite and tuff and concrete substrates, highlighting a high compatibility of the geopolymer binder with different kinds of materials. These features indicate a large potential for applications of these materials in Cultural Heritage.

  5. Potential applications of carbohydrases immobilization in the food industry.

    Science.gov (United States)

    Contesini, Fabiano Jares; de Alencar Figueira, Joelise; Kawaguti, Haroldo Yukio; de Barros Fernandes, Pedro Carlos; de Oliveira Carvalho, Patrícia; da Graça Nascimento, Maria; Sato, Hélia Harumi

    2013-01-11

    Carbohydrases find a wide application in industrial processes and products, mainly in the food industry. With these enzymes, it is possible to obtain different types of sugar syrups (viz. glucose, fructose and inverted sugar syrups), prebiotics (viz. galactooligossacharides and fructooligossacharides) and isomaltulose, which is an interesting sweetener substitute for sucrose to improve the sensory properties of juices and wines and to reduce lactose in milk. The most important carbohydrases to accomplish these goals are of microbial origin and include amylases (α-amylases and glucoamylases), invertases, inulinases, galactosidases, glucosidases, fructosyltransferases, pectinases and glucosyltransferases. Yet, for all these processes to be cost-effective for industrial application, a very efficient, simple and cheap immobilization technique is required. Immobilization techniques can involve adsorption, entrapment or covalent bonding of the enzyme into an insoluble support, or carrier-free methods, usually based on the formation of cross-linked enzyme aggregates (CLEAs). They include a broad variety of supports, such as magnetic materials, gums, gels, synthetic polymers and ionic resins. All these techniques present advantages and disadvantages and several parameters must be considered. In this work, the most recent and important studies on the immobilization of carbohydrases with potential application in the food industry are reviewed.

  6. Potential Applications of Carbohydrases Immobilization in the Food Industry

    Science.gov (United States)

    Contesini, Fabiano Jares; de Alencar Figueira, Joelise; Kawaguti, Haroldo Yukio; de Barros Fernandes, Pedro Carlos; de Oliveira Carvalho, Patrícia; Nascimento, Maria da Graça; Sato, Hélia Harumi

    2013-01-01

    Carbohydrases find a wide application in industrial processes and products, mainly in the food industry. With these enzymes, it is possible to obtain different types of sugar syrups (viz. glucose, fructose and inverted sugar syrups), prebiotics (viz. galactooligossacharides and fructooligossacharides) and isomaltulose, which is an interesting sweetener substitute for sucrose to improve the sensory properties of juices and wines and to reduce lactose in milk. The most important carbohydrases to accomplish these goals are of microbial origin and include amylases (α-amylases and glucoamylases), invertases, inulinases, galactosidases, glucosidases, fructosyltransferases, pectinases and glucosyltransferases. Yet, for all these processes to be cost-effective for industrial application, a very efficient, simple and cheap immobilization technique is required. Immobilization techniques can involve adsorption, entrapment or covalent bonding of the enzyme into an insoluble support, or carrier-free methods, usually based on the formation of cross-linked enzyme aggregates (CLEAs). They include a broad variety of supports, such as magnetic materials, gums, gels, synthetic polymers and ionic resins. All these techniques present advantages and disadvantages and several parameters must be considered. In this work, the most recent and important studies on the immobilization of carbohydrases with potential application in the food industry are reviewed. PMID:23344046

  7. Wind erosion potential after land application of biosolids

    Science.gov (United States)

    PI, H.; Sharratt, B. S.; Schillinger, W. F.; Bary, A.; Cogger, C.

    2017-12-01

    The world population is currently 7.6 billion and, along with continued population growth, comes the challenge of disposing of wastewater and sewage sludge (biosolids). Applying biosolids to agricultural land to replace synthetic fertilizers represents a relatively safe method to recycle or sustainably use biosolids. While land application of biosolids is recognized as a sustainable management practice for enhancing soil health, no studies have determined the effects of biosolids on soil wind erosion. Wind erosion potential of a silt loam was assessed using a portable wind tunnel after applying synthetic and biosolid fertilizer to conventional and conservation tillage practices during the summer fallow phase of a winter wheat-summer fallow rotation in 2015 and 2016 in east-central Washington. Little difference in soil loss was observed between biosolid and synthetic fertilizer treatments, but this result appeared to be dependent on susceptibility of the soil to erosion. Regression analysis between soil loss from fertilizer or tillage treatments indicated that soil loss was lower from biosolid versus synthetic fertilizer and conservation versus conventional tillage at high erosion rates. This suggests that biosolids may reduce wind erosion under highly erodible conditions. Meanwhile, heavy metal concentrations in the windblown sediment were similar for the biosolid and synthetic fertilizer treatments whereas metal loss in windblown sediment was 10% lower from biosolid than synthetic fertilizer. Our results indicate that land application of biosolids did not accelerate the loss of metals or nutrients from soils during high winds. KeywordsLand application of biosolids; wind erosion; wind tunnel; sustainable agriculture

  8. 7T: Physics, safety, and potential clinical applications.

    Science.gov (United States)

    Kraff, Oliver; Quick, Harald H

    2017-12-01

    With more than 60 installed magnetic resonance imaging (MRI) systems worldwide operating at a magnetic field strength of 7T or higher, ultrahigh-field (UHF) MRI has been established as a platform for clinically oriented research in recent years. Profound technical and methodological developments have helped overcome the inherent physical challenges of UHF radiofrequency (RF) signal homogenization in the human body. The ongoing development of dedicated RF coil arrays was pivotal in realizing UHF body MRI, beyond mere brain imaging applications. Another precondition to clinical application of 7T MRI is the safety testing of implants and the establishment of safety concepts. Against this backdrop, 7T MRI and MR spectroscopy (MRS) recently have demonstrated capabilities and potentials for clinical diagnostics in a variety of studies. This article provides an overview of the immanent physical challenges of 7T UHF MRI and discusses recent technical solutions and safety concepts. Furthermore, recent clinically oriented studies are highlighted that span a broad application spectrum from 7T UHF brain to body MRI. 4 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1573-1589. © 2017 International Society for Magnetic Resonance in Medicine.

  9. Potential Applications of Carbohydrases Immobilization in the Food Industry

    Directory of Open Access Journals (Sweden)

    Hélia Harumi Sato

    2013-01-01

    Full Text Available Carbohydrases find a wide application in industrial processes and products, mainly in the food industry. With these enzymes, it is possible to obtain different types of sugar syrups (viz. glucose, fructose and inverted sugar syrups, prebiotics (viz. galactooligossacharides and fructooligossacharides and isomaltulose, which is an interesting sweetener substitute for sucrose to improve the sensory properties of juices and wines and to reduce lactose in milk. The most important carbohydrases to accomplish these goals are of microbial origin and include amylases (α-amylases and glucoamylases, invertases, inulinases, galactosidases, glucosidases, fructosyltransferases, pectinases and glucosyltransferases. Yet, for all these processes to be cost-effective for industrial application, a very efficient, simple and cheap immobilization technique is required. Immobilization techniques can involve adsorption, entrapment or covalent bonding of the enzyme into an insoluble support, or carrier-free methods, usually based on the formation of cross-linked enzyme aggregates (CLEAs. They include a broad variety of supports, such as magnetic materials, gums, gels, synthetic polymers and ionic resins. All these techniques present advantages and disadvantages and several parameters must be considered. In this work, the most recent and important studies on the immobilization of carbohydrases with potential application in the food industry are reviewed.

  10. Flame Retardant Applications in Camping Tents and Potential Exposure.

    Science.gov (United States)

    Keller, Alexander S; Raju, Nikhilesh P; Webster, Thomas F; Stapleton, Heather M

    2014-02-11

    Concern has mounted over health effects caused by exposure to flame retardant additives used in consumer products. Significant research efforts have focused particularly on exposure to polybrominated diphenyl ethers (PBDEs) used in furniture and electronic applications. However, little attention has focused on applications in textiles, particularly textiles meeting a flammability standard known as CPAI-84. In this study, we investigated flame retardant applications in camping tents that met CPAI-84 standards by analyzing 11 samples of tent fabrics for chemical flame retardant additives. Furthermore, we investigated potential exposure by collecting paired samples of tent wipes and hand wipes from 27 individuals after tent setup. Of the 11 fabric samples analyzed, 10 contained flame retardant additives, which included tris(1,3-dichloroisopropyl) phosphate (TDCPP), decabromodiphenyl ether (BDE-209), triphenyl phosphate, and tetrabromobisphenol-A. Flame retardant concentrations were discovered to be as high as 37.5 mg/g (3.8% by weight) in the tent fabric samples, and TDCPP and BDE-209 were the most frequently detected in these samples. We also observed a significant association between TDCPP levels in tent wipes and those in paired hand wipes, suggesting that human contact with the tent fabric material leads to the transfer of the flame retardant to the skin surface and human exposure. These results suggest that direct contact with flame retardant-treated textiles may be a source of exposure. Future studies will be needed to better characterize exposure, including via inhalation and dermal sorption from air.

  11. Neural networks and their potential application to nuclear power plants

    International Nuclear Information System (INIS)

    Uhrig, R.E.

    1991-01-01

    A network of artificial neurons, usually called an artificial neural network is a data processing system consisting of a number of highly interconnected processing elements in an architecture inspired by the structure of the cerebral cortex portion of the brain. Hence, neural networks are often capable of doing things which humans or animals do well but which conventional computers often do poorly. Neural networks exhibit characteristics and capabilities not provided by any other technology. Neural networks may be designed so as to classify an input pattern as one of several predefined types or to create, as needed, categories or classes of system states which can be interpreted by a human operator. Neural networks have the ability to recognize patterns, even when the information comprising these patterns is noisy, sparse, or incomplete. Thus, systems of artificial neural networks show great promise for use in environments in which robust, fault-tolerant pattern recognition is necessary in a real-time mode, and in which the incoming data may be distorted or noisy. The application of neural networks, a rapidly evolving technology used extensively in defense applications, alone or in conjunction with other advanced technologies, to some of the problems of operating nuclear power plants has the potential to enhance the safety, reliability and operability of nuclear power plants. The potential applications of neural networking include, but are not limited to diagnosing specific abnormal conditions, identification of nonlinear dynamics and transients, detection of the change of mode of operation, control of temperature and pressure during start-up, signal validation, plant-wide monitoring using autoassociative neural networks, monitoring of check valves, modeling of the plant thermodynamics, emulation of core reload calculations, analysis of temporal sequences in NRC's ''licensee event reports,'' and monitoring of plant parameters

  12. Microbial siderophores and their potential applications: a review.

    Science.gov (United States)

    Saha, Maumita; Sarkar, Subhasis; Sarkar, Biplab; Sharma, Bipin Kumar; Bhattacharjee, Surajit; Tribedi, Prosun

    2016-03-01

    Siderophores are small organic molecules produced by microorganisms under iron-limiting conditions which enhance the uptake of iron to the microorganisms. In environment, the ferric form of iron is insoluble and inaccessible at physiological pH (7.35-7.40). Under this condition, microorganisms synthesize siderophores which have high affinity for ferric iron. These ferric iron-siderophore complexes are then transported to cytosol. In cytosol, the ferric iron gets reduced into ferrous iron and becomes accessible to microorganism. In recent times, siderophores have drawn much attention due to its potential roles in different fields. Siderophores have application in microbial ecology to enhance the growth of several unculturable microorganisms and can alter the microbial communities. In the field of agriculture, different types of siderophores promote the growth of several plant species and increase their yield by enhancing the Fe uptake to plants. Siderophores acts as a potential biocontrol agent against harmful phyto-pathogens and holds the ability to substitute hazardous pesticides. Heavy-metal-contaminated samples can be detoxified by applying siderophores, which explicate its role in bioremediation. Siderophores can detect the iron content in different environments, exhibiting its role as a biosensor. In the medical field, siderophore uses the "Trojan horse strategy" to form complexes with antibiotics and helps in the selective delivery of antibiotics to the antibiotic-resistant bacteria. Certain iron overload diseases for example sickle cell anemia can be treated with the help of siderophores. Other medical applications of siderophores include antimalarial activity, removal of transuranic elements from the body, and anticancer activity. The aim of this review is to discuss the important roles and applications of siderophores in different sectors including ecology, agriculture, bioremediation, biosensor, and medicine.

  13. Metabolic processes of Methanococcus maripaludis and potential applications.

    Science.gov (United States)

    Goyal, Nishu; Zhou, Zhi; Karimi, Iftekhar A

    2016-06-10

    Methanococcus maripaludis is a rapidly growing, fully sequenced, genetically tractable model organism among hydrogenotrophic methanogens. It has the ability to convert CO2 and H2 into a useful cleaner energy fuel (CH4). In fact, this conversion enhances in the presence of free nitrogen as the sole nitrogen source due to prolonged cell growth. Given the global importance of GHG emissions and climate change, diazotrophy can be attractive for carbon capture and utilization applications from appropriately treated flue gases, where surplus hydrogen is available from renewable electricity sources. In addition, M. maripaludis can be engineered to produce other useful products such as terpenoids, hydrogen, methanol, etc. M. maripaludis with its unique abilities has the potential to be a workhorse like Escherichia coli and S. cerevisiae for fundamental and experimental biotechnology studies. More than 100 experimental studies have explored different specific aspects of the biochemistry and genetics of CO2 and N2 fixation by M. maripaludis. Its genome-scale metabolic model (iMM518) also exists to study genetic perturbations and complex biological interactions. However, a comprehensive review describing its cell structure, metabolic processes, and methanogenesis is still lacking in the literature. This review fills this crucial gap. Specifically, it integrates distributed information from the literature to provide a complete and detailed view for metabolic processes such as acetyl-CoA synthesis, pyruvate synthesis, glycolysis/gluconeogenesis, reductive tricarboxylic acid (RTCA) cycle, non-oxidative pentose phosphate pathway (NOPPP), nitrogen metabolism, amino acid metabolism, and nucleotide biosynthesis. It discusses energy production via methanogenesis and its relation to metabolism. Furthermore, it reviews taxonomy, cell structure, culture/storage conditions, molecular biology tools, genome-scale models, and potential industrial and environmental applications. Through the

  14. Biomimetic design of a bacterial cellulose/hydroxyapatite nanocomposite for bone healing applications

    International Nuclear Information System (INIS)

    Zimmermann, Kristen A.; LeBlanc, Jill M.; Sheets, Kevin T.; Fox, Robert W.; Gatenholm, Paul

    2011-01-01

    This study describes the design and synthesis of bacterial cellulose/hydroxyapatite nanocomposites for bone healing applications using a biomimetic approach. Bacterial cellulose (BC) with various surface morphologies (pellicles and tubes) was negatively charged by the adsorption of carboxymethyl cellulose (CMC) to initiate nucleation of calcium-deficient hydroxyapatite (cdHAp). The cdHAp was grown in vitro via dynamic simulated body fluid (SBF) treatments over a one week period. Characterization of the mineralized samples was done with X-ray Photoelectron Spectroscopy (XPS) and Field Emission Scanning Electron Microscopy (FESEM) with Energy Dispersive Spectroscopy (EDS). The amount of cdHAp observed varied among different samples. XPS demonstrated that the atomic presence of calcium and phosphorus ranged from 0.44 at.% to 7.71 at.% Ca and 0.27 at.% to 11.18 at.% P. The Ca/P overall ratio ranged from 1.22 to 1.92. FESEM images showed that the cdHAp crystal size increased with increasing nanocellulose fibril density. To determine the viability of the scaffolds in vitro, the morphology and differentiation of osteoprogenitor cells was analyzed using fluorescence microscopy and alkaline phosphatase gene expression. The presence of cdHAp crystals on BC surfaces resulted in increased cell attachment.

  15. Staining procedure for the detection of microcracks: application to ewe bone.

    Science.gov (United States)

    Portero-Muzy, N R; Chavassieux, P M; Arlot, M E; Chapurlat, R D

    2011-10-01

    Microcracks are one of the determinants of the bone strength and their accumulation may contribute to increased fracture risk. They are detected after bulk staining with various dyes, including basic fuschin, calcein and xylenol orange. The duration of staining usually varies across types of bone and species. The ewe is a large animal with a bone remodeling similar to humans, used as an animal model in bone histomorphometry studies. The aim of the present study was to determine the optimal conditions for bulk staining with xylenol orange of ewe bone. Xylenol orange 5mM in 70% ethanol was applied to iliac crest and vertebral biopsies for 2 or 15 days or 1, 2 or 3 months. After embedding, sections of 40, 50 and 80 μm thick were cut with either a precision diamond wire saw or a microtome. The staining was not visible after 2 or 15 days and was heterogeneous after 1 or 2 months. The quality of 40 and 50 μm thick sections was not preserved compared with those of 80 μm. Microcracks were suitably observed on ewe bone after bulk staining with xylenol orange for 3 months, in 80 μm thick sections. We conclude that the staining procedures should differ when examining ewe or human bone. This may be due to differences in bone matrix composition. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. World’s First Clinical Case of Gene-Activated Bone Substitute Application

    Directory of Open Access Journals (Sweden)

    I. Y. Bozo

    2016-01-01

    Full Text Available Treatment of patients with large bone defects is a complex clinical problem. We have initiated the first clinical study of a gene-activated bone substitute composed of the collagen-hydroxyapatite scaffold and plasmid DNA encoding vascular endothelial growth factor. The first patient with two nonunions of previously reconstructed mandible was enrolled into the study. Scar tissues were excised; bone defects (5–14 mm between the mandibular fragments and nonvascularized rib-bone autograft were filled in with the gene-activated bone substitute. No adverse events were observed during 12 months of follow-up. In 3 months, the average density of newly formed tissues within the implantation zone was 402.21 ± 84.40 and 447.68 ± 106.75 HU in the frontal and distal regions, respectively, which correlated with the density of spongy bone. Complete distal bone defect repair with vestibular and lingual cortical plates formation was observed in 6 and 12 months after surgery; thereby the posterior nonunion was successfully eliminated. However, there was partial resorption of the proximal edge of the autograft entailed to relapse of the anterior nonunion. Thus, the first clinical data on the safety and efficacy of the gene-activated bone substitute were obtained. Given a high complexity of the clinical situation the treatment, results might be considered as promising. NCT02293031.

  17. Treadmill exercise with bone marrow stromal cells transplantation potentiates recovery of locomotor function after spinal cord injury in rats.

    Science.gov (United States)

    Kim, You-Mi; Seo, Tae-Beom; Kim, Chang-Ju; Ji, Eun-Sang

    2017-06-01

    Transplantation of bone marrow stromal cells (BMSCs) is regarded as a promising candidate for the spinal cord injury (SCI). In the present study, we investigated whether treadmill exercise potentiate the effect of BM-SCs transplantation on the functional recovery in the SCI rats. The spinal cord contusion injury applied at the T9-T10 level using the impactor. Cultured BMSCs were transplanted into the lesion at 1 week after SCI induction. Treadmill exercise was conducted for 6 weeks. Basso-Beattie-Bresnahan (BBB) scale for locomotor function was determined. Sprouting axons in the lesion cavity were detected by immunofluorescence staining for neurofilament-200. Brain-derived neurotrophic factor (BDNF) and synapsin-I expressions were analyzed using western blotting. BMSCs transplantation improved BBB score and increased expressions of neurofilament-200, BDNF, and synapsin-I in the SCI rats. Treadmill exercise potentiated the improving effect of BMSCs transplantation on BBB score in the SCI rats. This potentiating effect of treadmill exercise could be ascribed to the enhancement of BDNF expression in the SCI rats.

  18. In situ vitrification: Demonstrated capabilities and potential applications

    International Nuclear Information System (INIS)

    Luey, J.K.

    1993-01-01

    A large-scale demonstration of the in situ vitrification (ISV) process was performed in April 1990 on the 116-B-6A Crib in the 100 Area of the Hanford Site in southeastern Washington. The 116-B-6A Crib is a radioactive mixed waste site and was selected to demonstrate the applicability of ISV to soils contaminated with mixed wastes common to many US Department of Energy (DOE) sites. Results from the demonstration show that the ISV process is a viable remediation technology for contaminated soils. The demonstration of the ISV process on an actual contaminated soil site followed research and development efforts by the Pacific Northwest Laboratory (PNL) over the last 10 years. PNL's research has led to the development of the ISV process as a viable remediation technology for contaminated soils and the creation of a commercial supplier of ISV services, Geosafe Corporation. Development efforts for ISV applications other than treatment of contaminated soils, by PNL and in collaboration with Oak Ridge National Laboratory (ORNL) and Idaho National Engineering Laboratory (INEL), show the ISV process has potential applicability for remediating buried waste sites, remediating underground storage tanks, and enabling the placement of subsurface vitrified barriers and engineered structures. This paper discusses the results from the April 1990 large-scale demonstration and provides a general overview of the current capabilities of the ISV process for contaminated soils. In addition, this paper outlines some of the technical issues associated with other ISV applications and provides a qualitative discussion of the level of effort needed to resolve these technical issues

  19. Evanescent field: A potential light-tool for theranostics application

    Science.gov (United States)

    Polley, Nabarun; Singh, Soumendra; Giri, Anupam; Pal, Samir Kumar

    2014-03-01

    A noninvasive or minimally invasive optical approach for theranostics, which would reinforce diagnosis, treatment, and preferably guidance simultaneously, is considered to be major challenge in biomedical instrument design. In the present work, we have developed an evanescent field-based fiber optic strategy for the potential theranostics application in hyperbilirubinemia, an increased concentration of bilirubin in the blood and is a potential cause of permanent brain damage or even death in newborn babies. Potential problem of bilirubin deposition on the hydroxylated fiber surface at physiological pH (7.4), that masks the sensing efficacy and extraction of information of the pigment level, has also been addressed. Removal of bilirubin in a blood-phantom (hemoglobin and human serum albumin) solution from an enhanced level of 77 μM/l (human jaundice >50 μM/l) to ˜30 μM/l (normal level ˜25 μM/l in human) using our strategy has been successfully demonstrated. In a model experiment using chromatography paper as a mimic of biological membrane, we have shown efficient degradation of the bilirubin under continuous monitoring for guidance of immediate/future course of action.

  20. Resorption behavior of a nanostructured bone substitute: in vitro investigation and clinical application.

    Science.gov (United States)

    Reichert, Christoph; Götz, Werner; Reimann, Susanne; Keilig, Ludger; Hagner, Martin; Bourauel, Christoph; Jäger, Andreas

    2013-03-01

    To develop an in vitro assay for quantitative analysis of the degradation to which a bone substitute is exposed by osteoclasts. The aim of establishing this method was to improve the predictability of carrying out tooth movements via bone substitutes and to provide a basis for verification in exemplary clinical cases. After populating a bone substitute (NanoBone®; ArtOss, Germany) with osteoclastic cells, inductively-coupled mass spectrometry was used to evaluate changing calcium levels in the culture medium as a marker of resorption activity. It was observed that calcium levels increased substantially in the culture medium with the cells populating the bone substitute. This in vitro assay is a valid method that can assist clinicians in selecting the appropriate materials for certain patients. While tooth movements occurring through this material were successful, uncertainty about the approach will remain as long-term results are not available.

  1. Audiometric results of bilateral bone-anchored hearing aid application in patients with bilateral congenital aural atresia.

    Science.gov (United States)

    van der Pouw, K T; Snik, A F; Cremers, C W

    1998-04-01

    The effect of bilateral application of bone-anchored hearing aids (BAHAs) was examined in terms of directional hearing and speech recognition in quiet and in noise in four patients with bilateral congenital atresia who, out of pure necessity, had been using a unilateral bone-conduction hearing aid since early life. This study comprised a prospective clinical evaluation in a single subject design; four patients with bilateral congenital atresia originating from the Nijmegen BAHA series participated. Three patients had Treacher Collins syndrome. All four patients had conductive, most probably, symmetrical, hearing loss. Recently these patients had applied for a second BAHA and were subsequently fitted bilaterally. With two BAHAs, all four patients showed significant improvement in sound localization. Also, speech perception in quiet showed significant improvement with bilateral application, and a significant improvement was found in speech perception in noise in three patients. These results suggest that patients with congenital conductive, symmetrical hearing loss will benefit from bilateral BAHAs.

  2. Mesenchymal stem cells: biological characteristics and potential clinical applications

    DEFF Research Database (Denmark)

    Kassem, Moustapha

    2004-01-01

    Mesenchymal stem cells (MSC) are clonogenic, non-hematpoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages, for example, osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages, for example, neuronal...

  3. Collagen type I from bovine bone. Effect of animal age, bone anatomy and drying methodology on extraction yield, self-assembly, thermal behaviour and electrokinetic potential

    OpenAIRE

    Ferraro, Vincenza; Gaillard-Martinie, Brigitte; Sayd, Thierry; Chambon, Christophe; Anton, Marc; Sante-Lhoutellier, Veronique

    2017-01-01

    Natural collagen is easily available from animal tissues such as bones. Main limitations reported in the use of natural collagen are heterogeneity and loss of integrity during recovery. However, its natural complexity, functionality and bioactivity still remain to be achieved through synthetic and recombinant ways. Variability of physicochemical prope...

  4. Potential biotechnological application of microalgae: a critical review.

    Science.gov (United States)

    Odjadjare, Ejovwokoghene C; Mutanda, Taurai; Olaniran, Ademola O

    2017-02-01

    Microalgae are diverse microorganisms inhabiting a wide range of habitats with only a small fraction being cultivated for human use. Recently, interest in microalgal research has increased in the quest for alternative renewable fuels due to possible depletion of fossil fuels in the near future. However, costly downstream processing has hampered the commercialization of biofuels derived from microalgae. Several value added products of industrial, pharmaceutical and agricultural relevance could be simultaneously derived from microalgae during bioenergy production. Despite these value-added products having the potential to offset the high cost of downstream processing of renewable fuels, their production has not been explored in-depth. This review presents a critical overview of the current state of biotechnological applications of microalgae for human benefit and highlights possible areas for further research and development.

  5. Bee venom therapy: Potential mechanisms and therapeutic applications.

    Science.gov (United States)

    Zhang, Shuai; Liu, Yi; Ye, Yang; Wang, Xue-Rui; Lin, Li-Ting; Xiao, Ling-Yong; Zhou, Ping; Shi, Guang-Xia; Liu, Cun-Zhi

    2018-04-11

    Bee venom is a very complex mixture of natural products extracted from honey bee which contains various pharmaceutical properties such as peptides, enzymes, biologically active amines and nonpeptide components. The use of bee venom into the specific points is so called bee venom therapy, which is widely used as a complementary and alternative therapy for 3000 years. A growing number of evidence has demonstrated the anti-inflammation, the anti-apoptosis, the anti-fibrosis and the anti-arthrosclerosis effects of bee venom therapy. With these pharmaceutical characteristics, bee venom therapy has also been used as the therapeutic method in treating rheumatoid arthritis, amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, liver fibrosis, atherosclerosis, pain and others. Although widely used, several cases still reported that bee venom therapy might cause some adverse effects, such as local itching or swelling. In this review, we summarize its potential mechanisms, therapeutic applications, and discuss its existing problems. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Assessment of potential solder candidates for high temperature applications

    DEFF Research Database (Denmark)

    of the package with different solders of different melting temperatures. High Pb containing alloys where the lead levels can be above 85% by weight, is one of the solders currently being used in this technology. Responding to market pressure i.e. need for green electronic products there is now an increasing......Multi-Chip module (MCM) technology is a specialized electronic packaging technology recently gaining momentum due to the miniaturization drive in the microelectronics industry. The step soldering approach is being employed in the MCM technology. This method is used to solder various levels...... pressure to eliminate lead containing materials despite the fact that materials for high Pb containing alloys are currently not affected by any legislations. A tentative assessment was carried out to determine the potential solder candidates for high temperature applications based on the solidification...

  7. Current and potential applications of bismuth-based drugs.

    Science.gov (United States)

    Keogan, Donal M; Griffith, Darren M

    2014-09-23

    : Bismuth compounds have been used extensively as medicines and in particular for the treatment of gastrointestinal ailments. In addition to bismuth's well known gastroprotective effects and efficacy in treating H. pylori infection it also has broad anti-microbial, anti-leishmanial and anti-cancer properties. Aspects of the biological chemistry of bismuth are discussed and biomolecular targets associated with bismuth treatment are highlighted. This review strives to provide the reader with an up to date account of bismuth-based drugs currently used to treat patients and discuss potential medicinal applications of bismuth drugs with reference to recent developments in the literature. Ultimately this review aims to encourage original contributions to this exciting and important field.

  8. A systematic review of the concept and clinical applications of bone marrow aspirate concentrate in tendon pathology

    Directory of Open Access Journals (Sweden)

    Imam Mohamed A.

    2017-01-01

    Full Text Available Tendon pathologies are a group of musculoskeletal conditions frequently seen in clinical practice. They can be broadly classified into traumatic, degenerative and overuse-related tendinopathies. Rotator cuff tears, Achilles tendinopathy and tennis elbow are common examples of these conditions. Conventional treatments have shown inconsistent outcomes and might fail to provide satisfactory clinical improvement. With the growing trend towards the use of mesenchymal stem cells (MSCs in other branches of medicine, there is an increasing interest in treating tendon pathologies using the bone marrow MSC. In this article, we provide a systematic literature review documenting the current status of the use of bone marrow aspirate concentrate (BMAC for the treatment of tendon pathologies. We also asked the question on the safety of BMAC and whether there are potential complications associated with BMAC therapy. Our hypothesis is that the use of BMAC provides safe clinical benefit when used for the treatment of tendinopathy or as a biological augmentation of tendon repair. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA checklist while preparing this systematic review. A literature search was carried out including the online databases of PubMed, EMBASE, ClinicalTrial.gov and the Cochrane Library from 1960 to the end of May 2015. Relevant studies were selected and critically appraised. Data from eligible studies were extracted and classified per type of tendon pathology. We included 37 articles discussing the application and use of BMAC for the treatment of tendon pathologies. The Critical Appraisal Skills Program (CASP appraisal confirmed a satisfactory standard of 37 studies. Studies were sub-categorised into: techniques of extraction, processing and microscopic examination of BMAC (n = 18, where five studies looked at the evaluation of aspiration techniques (n = 5, augmentation of rotator cuff tears (n = 5

  9. Probabilistic empirical prediction of seasonal climate: evaluation and potential applications

    Science.gov (United States)

    Dieppois, B.; Eden, J.; van Oldenborgh, G. J.

    2017-12-01

    Preparing for episodes with risks of anomalous weather a month to a year ahead is an important challenge for governments, non-governmental organisations, and private companies and is dependent on the availability of reliable forecasts. The majority of operational seasonal forecasts are made using process-based dynamical models, which are complex, computationally challenging and prone to biases. Empirical forecast approaches built on statistical models to represent physical processes offer an alternative to dynamical systems and can provide either a benchmark for comparison or independent supplementary forecasts. Here, we present a new evaluation of an established empirical system used to predict seasonal climate across the globe. Forecasts for surface air temperature, precipitation and sea level pressure are produced by the KNMI Probabilistic Empirical Prediction (K-PREP) system every month and disseminated via the KNMI Climate Explorer (climexp.knmi.nl). K-PREP is based on multiple linear regression and built on physical principles to the fullest extent with predictive information taken from the global CO2-equivalent concentration, large-scale modes of variability in the climate system and regional-scale information. K-PREP seasonal forecasts for the period 1981-2016 will be compared with corresponding dynamically generated forecasts produced by operational forecast systems. While there are many regions of the world where empirical forecast skill is extremely limited, several areas are identified where K-PREP offers comparable skill to dynamical systems. We discuss two key points in the future development and application of the K-PREP system: (a) the potential for K-PREP to provide a more useful basis for reference forecasts than those based on persistence or climatology, and (b) the added value of including K-PREP forecast information in multi-model forecast products, at least for known regions of good skill. We also discuss the potential development of

  10. Porous bone radio sterilized chips and their clinical application in vertebral arthrodesis

    International Nuclear Information System (INIS)

    Luna Z, D.; Ortega E, J.; Zayas M, L. A.; Diaz M, I.

    2011-11-01

    The diseases of the muscle-skeletal tissue are the main cause of physical disability which affects in the entire world to millions of people. The bone is part of the muscle-skeletal tissue and the spine is a group of bones that are located in the dorsal part of the human body. At present the spine lesions are varied as those that people suffer when they have automobile accidents of for fallen, mainly in the major adults, if the spine lesions are not treated appropriately they can have consequences to short or long term. A procedure that has been useful for the spine lesions is the vertebral arthrodesis. The tissue banks are places where is obtained bone of distinct origin for clinical use, the chips of porous bone are obtained in banks of specialized tissues which are sterilized with gamma radiation of cobalt-60, the use of this bone type has been demonstrated that these help in the recovery of patients that suffer spine fracture. In this work the process of procurement of human bone is presented, just as the process of its transformation in chips form and its sterilization method. At the end a case of a young patient is presented who suffers an automobile accident and was treated by the vertebral arthrodesis technique of spine, using chips of porous bone for his recovery. (Author)

  11. Evaluation of Biocompatibility and Osteogenic Potential of Tricalcium Silicate-based Cements Using Human Bone Marrow-derived Mesenchymal Stem Cells.

    Science.gov (United States)

    Sultana, Neha; Singh, Manisha; Nawal, Ruchika Roongta; Chaudhry, Sarika; Yadav, Seema; Mohanty, Sujata; Talwar, Sangeeta

    2018-03-01

    The success of endodontic regeneration lies in the appropriate combination of stem cells and bioactive materials. Several novel dental materials are available on the market in this regard. Hence, the current study aimed to evaluate the proliferation, differentiation, and osteogenic potential of human bone marrow-derived mesenchymal stem cells (hBMSCs) onto biomaterials like ProRoot MTA (MTA; Dentsply Tulsa Dental, Tulsa, OK), Biodentine (BD; Septodont, Saint Maur de Fosses, France), and EndoSequence Root Repair Material (ERRM; Brasseler USA, Savannah, GA). Dental cements were formulated into discs and assessed for their biocompatibility. hBMSCs were used to study biocompatitibility and the proliferative and osteogenic potential of these dental cements. A live dead assay was performed using confocal microscopy to study the biocompatibility, proliferation, and cell attachment property of the cements. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was also performed on days 1, 3, 5, and 7 to study growth kinetics. The osteogenic potential of these cements was studied by inducing hBMSCs over them using osteogenic differentiation medium (assessed by alkaline phosphatase assay). ERRM and MTA have shown the best biocompatibility among the tricalcium silicate materials used with no significant difference between them. Both have shown significantly higher osteogenic bioactivity than BD. All 3 tricalcium silicate cements support good adherence of hBMSCs. All of the dental cements used in this study are biocompatible with the potential to induce proliferation and osteogenic differentiation of hBMSCs. Therefore, the newly introduced ERRM can be the material of choice in various endodontic applications. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Serum Heme Oxygenase-1 and BMP-7 Are Potential Biomarkers for Bone Metabolism in Patients with Rheumatoid Arthritis and Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Tong-ling Yuan

    2016-01-01

    Full Text Available Backgrounds. Heme oxygenase-1 (HO-1 has been reported to play a regulatory role in osteoclastogenesis. Bone morphogenetic protein (BMP pathways induce osteoblastic differentiation and bone remodeling. Aims. To identify serum levels of HO-1, BMP-7, and Runt related-transcription factor 2 (Runx2 in patients with rheumatoid arthritis (RA and ankylosing spondylitis (AS and to investigate the relationships between HO-1, BMP-7, Runx2, and other common biomarkers for bone metabolism. Results. Serum levels of HO-1 and BMP-7 were revealed to be significantly higher in patients with RA or AS than in healthy controls (p<0.01. In RA group, HO-1 was positively correlated with BMP-7, Runx2, and tartrate-resistant acid phosphatase-5b (TRAP-5b (p<0.05, resp., BMP-7 was positively correlated with Runx2 and TRAP-5b (p<0.05, resp., and Runx2 was negatively correlated with N-terminal midfragment of osteocalcin (NMID (p<0.05. In AS group, we observed identical correlation between HO-1 and BMP-7, but opposite correlations between BMP-7 and TRAP-5b and between Runx2 and NMID, when comparing with the RA cohort. Conclusion. Our findings suggest that HO-1 and BMP-7 are potential biomarkers for bone metabolism in patients with RA and AS. The different correlations between the bone markers point to distinct differences in bone remodeling pathways in the two types of arthritis.

  13. Bone ingrowth potential of electron beam and selective laser melting produced trabecular-like implant surfaces with and without a biomimetic coating.

    Science.gov (United States)

    Biemond, J E; Hannink, G; Verdonschot, N; Buma, P

    2013-03-01

    The bone ingrowth potential of trabecular-like implant surfaces produced by either selective laser melting (SLM) or electron beam melting (EBM), with or without a biomimetic calciumphosphate coating, was examined in goats. For histological analysis and histomorphometry of bone ingrowth depth and bone implant contact specimens were implanted in the femoral condyle of goats. For mechanical push out tests to analyse mechanical implant fixation specimens were implanted in the iliac crest. The follow up periods were 4 (7 goats) and 15 weeks (7 goats). Both the SLM and EBM produced trabecular-like structures showed a variable bone ingrowth after 4 weeks. After 15 weeks good bone ingrowth was found in both implant types. Irrespective to the follow up period, and the presence of a coating, no histological differences in tissue reaction around SLM and EBM produced specimens was found. Histological no coating was detected at 4 and 15 weeks follow up. At both follow up periods the mechanical push out strength at the bone implant interface was significantly lower for the coated SLM specimens compared to the uncoated SLM specimens. The expected better ingrowth characteristics and mechanical fixation strength induced by the coating were not found. The lower mechanical strength of the coated specimens produced by SLM is a remarkable result, which might be influenced by the gross morphology of the specimens or the coating characteristics, indicating that further research is necessary.

  14. The use and potential application of electron accelerator in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Danu, Sugiarto [National Nuclear Energy Agency, Center for Research and Development of Isotopes and Radiation Technology, Jakarta (Indonesia)

    2003-02-01

    The use of electron accelerator in Indonesia for research and development, radiation services, commercial purposes and potential application in the future is described. A pilot plant for radiation curing technology particularly for wood surface coating using low energy electron accelerator (300 keV, 50 mA; installed in 1984) and a EBM GJ 2 (2 MeV, 10 mA, installed in 1994) for R and D of crosslinking process such as wire and cable and heat shrinkable tube and sheets in Center for Research and Development of Isotopes and Radiation Technology, Jakarta, and also a low energy electron accelerator (installed in 1998) in a private company, PT Gajah Tunggai, are being mainly used. Their performances are presented with activities achieved in the fields of wood surface coating, vulcanization of natural rubber latex, grafting of polyethylene terephthalate (PET), radiation sterilization, degradation of cellulose and, as promising applications, radiation curing for composite production and uses for environmental preservation are introduced. (S. Ohno)

  15. Potential of low-temperature nuclear heat applications

    International Nuclear Information System (INIS)

    1986-12-01

    At present, more than one third of the fossil fuel currently used is being consumed to produce space heating and to meet industrial needs in many countries of the world. Imported oil still represents a large portion of this fossil fuel and despite its present relatively low price future market evolutions with consequent upward cost revisions cannot be excluded. Thus the displacement of the fossil fuel by cheaper low-temperature heat produced in nuclear power plants is a matter which deserves careful consideration. Technico-economic studies in many countries have shown that the use of nuclear heat is fully competitive with most of fossil-fuelled plants, the higher investment costs being offset by lower production cost. Another point in favour of heat generation by nuclear source is its indisputable advantage in terms of benefits to the environment. The IAEA activity plans for 1985-86 concentrate on information exchange with specific emphasis on the design criteria, operating experience, safety requirements and specifications of heat-only reactors, co-generation plants and existing power plants backfitted for additional heat applications. The information gained up to 1985 was discussed during the Advisory Group Meeting on the Potential of Low-Temperature Nuclear Heat Applications held in the Federal Institute for Reactor Research, Wuerenlingen, Switzerland in September 1985 and, is included in the present Technical Document

  16. The use and potential application of electron accelerator in Indonesia

    International Nuclear Information System (INIS)

    Danu, Sugiarto

    2003-01-01

    The use of electron accelerator in Indonesia for research and development, radiation services, commercial purposes and potential application in the future is described. A pilot plant for radiation curing technology particularly for wood surface coating using low energy electron accelerator (300 keV, 50 mA; installed in 1984) and a EBM GJ 2 (2 MeV, 10 mA, installed in 1994) for R and D of crosslinking process such as wire and cable and heat shrinkable tube and sheets in Center for Research and Development of Isotopes and Radiation Technology, Jakarta, and also a low energy electron accelerator (installed in 1998) in a private company, PT Gajah Tunggai, are being mainly used. Their performances are presented with activities achieved in the fields of wood surface coating, vulcanization of natural rubber latex, grafting of polyethylene terephthalate (PET), radiation sterilization, degradation of cellulose and, as promising applications, radiation curing for composite production and uses for environmental preservation are introduced. (S. Ohno)

  17. Bone Marrow Therapies for Chronic Heart Disease.

    Science.gov (United States)

    Behbahan, Iman Saramipoor; Keating, Armand; Gale, Robert Peter

    2015-11-01

    Chronic heart failure is a leading cause of death. The demand for new therapies and the potential regenerative capacity of bone marrow-derived cells has led to numerous clinical trials. We critically discuss current knowledge of the biology and clinical application of bone marrow cells. It appears unlikely that bone marrow cells can develop into functional cardiomyocyte after infusion but may have favorable paracrine effects. Most, but not all, clinical trials report a modest short- but not long-term benefit of infusing bone marrow-derived cells. Effect size appears to correlate with stringency of study-design: the most stringent trials report the smallest effect-sizes. We conclude there may be short- but not substantial long-term benefit of infusing bone marrow-derived cells into persons with chronic heart failure and any benefit observed is unlikely to result from trans-differentiation of bone marrow-derived cells into functioning cardiomyocytes. © 2015 AlphaMed Press.

  18. Statistical shape and appearance models of bones.

    Science.gov (United States)

    Sarkalkan, Nazli; Weinans, Harrie; Zadpoor, Amir A

    2014-03-01

    When applied to bones, statistical shape models (SSM) and statistical appearance models (SAM) respectively describe the mean shape and mean density distribution of bones within a certain population as well as the main modes of variations of shape and density distribution from their mean values. The availability of this quantitative information regarding the detailed anatomy of bones provides new opportunities for diagnosis, evaluation, and treatment of skeletal diseases. The potential of SSM and SAM has been recently recognized within the bone research community. For example, these models have been applied for studying the effects of bone shape on the etiology of osteoarthritis, improving the accuracy of clinical osteoporotic fracture prediction techniques, design of orthopedic implants, and surgery planning. This paper reviews the main concepts, methods, and applications of SSM and SAM as applied to bone. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Temporal bone imaging

    International Nuclear Information System (INIS)

    Shaffer, K.A.

    1987-01-01

    Although pluridirectional tomography had been the standard method to evaluate the temporal bone, computed tomography has replaced it for nearly all applications. Magnetic resonance imaging can demonstrate nonosseous temporal bone structures as well

  20. Magnetic resonance imaging of the bone marrow in hematological malignancies

    International Nuclear Information System (INIS)

    Berg, B.C. vande; Lecouvet, F.E.; Maldague, B.; Malghem, J.; Michaux, L.; Ferrant, A.

    1998-01-01

    Despite its lack of specificity, magnetic resonance imaging (MRI) of the bone marrow has the potential to play a role in the management of patients with primary neoplastic disorders of the hematopoietic system, including lymphomas, leukemias and multiple myeloma. In addition to its use in the assessment of suspected spinal cord compression, bone marrow MRI could be used as a prognostic method or as a technique to assess the response to treatment. The current review addresses the common patterns of bone marrow involvement observed in primary neoplasms of the bone marrow, basic technical principles of bone marrow MRI, and several applications of MRI in selected clinical situations. (orig.) (orig.)

  1. Potential application of biodrying to treat solid waste

    Science.gov (United States)

    Zaman, Badrus; Oktiawan, Wiharyanto; Hadiwidodo, Mochtar; Sutrisno, Endro; Purwono; Wardana, Irawan Wisnu

    2018-02-01

    The generation of solid waste around the world creates problems if not properly managed. The method of processing solid waste by burning or landfill is currently not optimal. The availability of land where the final processing (TPA) is critical, looking for a new TPA alternative will be difficult and expensive, especially in big cities. The processing of solid waste using bio drying technology has the potential to produce renewable energy and prevention of climate change. Solid waste processing products can serve as Refuse Derived Fuel (RDF), reduce water content of solid waste, meningkatkan kualitas lindi and increase the amount of recycled solid waste that is not completely separated from home. Biodrying technology is capable of enhancing the partial disintegration and hydrolysis of macromolecule organic compounds (such as C-Organic, cellulose, hemicellulose, lignin, total nitrogen). The application of biodrying has the potential to reduce greenhouse gas emissions such as carbon dioxide (CO2), methane (CH4), and dinitrooksida (N2O). These gases cause global warming.

  2. RBC micromotors carrying multiple cargos towards potential theranostic applications.

    Science.gov (United States)

    Wu, Zhiguang; Esteban-Fernández de Ávila, Berta; Martín, Aída; Christianson, Caleb; Gao, Weiwei; Thamphiwatana, Soracha Kun; Escarpa, Alberto; He, Qiang; Zhang, Liangfang; Wang, Joseph

    2015-08-28

    Red blood cell (RBC)-based micromotors containing both therapeutic and diagnostic modalities are described as a means for potential theranostic applications. In this natural RBC-based multicargo-loaded micromotor system, quantum dots (QDs), anti-cancer drug doxorubicin (DOX), and magnetic nanoparticles (MNPs), were co-encapsulated into RBC micromotors. The fluorescent emission of both QDs and DOX provides direct visualization of their loading inside the RBC motors at two distinct wavelengths. The presence of MNPs within the RBCs allows for efficient magnetic guidance under ultrasound propulsion along with providing the potential for magnetic resonance imaging. The simultaneous encapsulation of the imaging nanoparticles and therapeutic payloads within the same RBC micromotor has a minimal effect upon its propulsion behavior. The ability of the RBC micromotors to transport imaging and therapeutic agents at high speed and spatial precision through a complex microchannel network is also demonstrated. Such ability to load and transport diagnostic imaging agents and therapeutic drugs within a single cell-based motor, in addition to a lower toxicity observed once the drug is encapsulated within the multicargo RBC motor, opens the door to the development of theranostic micromotors that may simultaneously treat and monitor diseases.

  3. Potential application of biodrying to treat solid waste

    Directory of Open Access Journals (Sweden)

    Zaman Badrus

    2018-01-01

    Full Text Available The generation of solid waste around the world creates problems if not properly managed. The method of processing solid waste by burning or landfill is currently not optimal. The availability of land where the final processing (TPA is critical, looking for a new TPA alternative will be difficult and expensive, especially in big cities. The processing of solid waste using bio drying technology has the potential to produce renewable energy and prevention of climate change. Solid waste processing products can serve as Refuse Derived Fuel (RDF, reduce water content of solid waste, meningkatkan kualitas lindi and increase the amount of recycled solid waste that is not completely separated from home. Biodrying technology is capable of enhancing the partial disintegration and hydrolysis of macromolecule organic compounds (such as C-Organic, cellulose, hemicellulose, lignin, total nitrogen. The application of biodrying has the potential to reduce greenhouse gas emissions such as carbon dioxide (CO2, methane (CH4, and dinitrooksida (N2O. These gases cause global warming.

  4. Saffron: a natural product with potential pharmaceutical applications.

    Science.gov (United States)

    Christodoulou, Eirini; Kadoglou, Nikolaos P E; Kostomitsopoulos, Nikolaos; Valsami, Georgia

    2015-12-01

    Recently, a great deal of interest has been developed to isolate and investigate novel bioactive components from natural resources with health beneficial effects. Saffron is the dried stigma of Crocus sativus L. and has been used for centuries in traditional medicine mainly for its healing properties, as well as for the treatment of various pathological conditions. Objectives of the present review are to unravel its therapeutic properties and investigate the potential applications of saffron in contemporary therapy of a wide spectrum of diseases and summarize previous and current evidence regarding the biological/pharmacological activities of saffron and its active ingredients and their possible therapeutic uses. Recent phytochemistry and pharmacological experiments have indicated that crocin and safranal, the major active ingredients of saffron, exert important actions, such as antioxidant, anti-tumor, anti-diabetic, anti-inflammatory and anti-atherosclerotic. Unfortunately, the vast majority of those data derive from in vitro studies, whereas a limited number of in vivo experiments support the aforementioned effects. In addition to studies with mechanistic implications, very few clinical trials provide preliminary evidence of saffron potentiality to alleviate depression and increase cognitive function in patients with Alzheimer's disease. The history and structural features of saffron constituents are given in the first part of the review, followed by a comprehensive and critical presentation of the published preclinical and clinical studies and review papers on the pharmacology and possible therapeutic uses of saffron and its main active components crocin and safranal. © 2015 Royal Pharmaceutical Society.

  5. Potential applications of a small HTR-GT

    International Nuclear Information System (INIS)

    Crommelin, G.A.K.

    1998-01-01

    In the first half of this year the INCOGEN pre-feasibility study has been finished. In view of the title of this meeting this paper deals with some aspects concerning the non-technical side of this study: the potential applications and the possibilities to open up markets, in other words how to achieve the most promising future for nuclear energy generation for the small power range. To open up any market one must accept that there is a strong relation between the price based upon through life costing and social acceptance, in other words a requirement of safety, good performance, reliability, an easily understandable reactor design, energy conversion unit and controls. The approach to this relationship will be from the potential user's point of view and will use several well-proven thoughts and tools from the gas turbine and warship design branches. For the HTR-GT to be used in the small power range, competitive costs seems to be the biggest challenge and should get a maximum of attention. 8 refs

  6. Insights into lignin degradation and its potential industrial applications.

    Science.gov (United States)

    Abdel-Hamid, Ahmed M; Solbiati, Jose O; Cann, Isaac K O

    2013-01-01

    Lignocellulose is an abundant biomass that provides an alternative source for the production of renewable fuels and chemicals. The depolymerization of the carbohydrate polymers in lignocellulosic biomass is hindered by lignin, which is recalcitrant to chemical and biological degradation due to its complex chemical structure and linkage heterogeneity. The role of fungi in delignification due to the production of extracellular oxidative enzymes has been studied more extensively than that of bacteria. The two major groups of enzymes that are involved in lignin degradation are heme peroxidases and laccases. Lignin-degrading peroxidases include lignin peroxidase (LiP), manganese peroxidase (MnP), versatile peroxidase (VP), and dye-decolorizing peroxidase (DyP). LiP, MnP, and VP are class II extracellular fungal peroxidases that belong to the plant and microbial peroxidases superfamily. LiPs are strong oxidants with high-redox potential that oxidize the major non-phenolic structures of lignin. MnP is an Mn-dependent enzyme that catalyzes the oxidation of various phenolic substrates but is not capable of oxidizing the more recalcitrant non-phenolic lignin. VP enzymes combine the catalytic activities of both MnP and LiP and are able to oxidize Mn(2+) like MnP, and non-phenolic compounds like LiP. DyPs occur in both fungi and bacteria and are members of a new superfamily of heme peroxidases called DyPs. DyP enzymes oxidize high-redox potential anthraquinone dyes and were recently reported to oxidize lignin model compounds. The second major group of lignin-degrading enzymes, laccases, are found in plants, fungi, and bacteria and belong to the multicopper oxidase superfamily. They catalyze a one-electron oxidation with the concomitant four-electron reduction of molecular oxygen to water. Fungal laccases can oxidize phenolic lignin model compounds and have higher redox potential than bacterial laccases. In the presence of redox mediators, fungal laccases can oxidize non

  7. Potential ternary compounds for first wall fusion applications

    International Nuclear Information System (INIS)

    O'Connor, D.J.; Kisi, E.; Riley, D.; Healy, M.

    2005-01-01

    The demands placed on a first wall in a fusion facility are both numerous and demanding. In most cases up till now, the materials considered have largely been elemental or two component alloys but so far none have met the demanding benchmarks for a practical solution for long term applications. A family of compounds, call MAX Phases, cover a broad range of elements and have very promising synthesis properties as well as physical properties which indicate that they are well placed to be considered as potential candidates. There are over 600 compounds in this family though only 50 known have been synthesised so far, so it is not yet possible to claim a thorough study has been undertaken of this class of material. An examination of the properties of just one compound, Ti 3 SiC 2 , shows the potential for this class of materials. Consideration of Ti 3 SiC 2 is based on the earlier work on TiC and SiC as potential first wall materials. As a three element material Ti 3 SiC 2 is essentially a machineable ceramic with exceptional properties and is suited to both mechanical and electrical applications. Ti 3 SiC 2 has the high temperature and chemical resistance of a ceramic combined with a degree of ductility and a higher electrical conductivity than pure Ti. Furthermore, the material has far higher thermal conductivity than commercial stainless steel or Ti alloys, and although it has a high fracture toughness at high temperatures, it can be machined using conventional hardened steel tools. It exhibits excellent damage tolerance and good thermal shock resistance. Ti 3 SiC 2 has the advantage that there are a number of synthesis processes established which provide the opportunity to tailor the synthesis to meet specialist needs. One form of manufacture, called Self-Propagation High-Temperature Synthesis (SHS) promises to both form large quantities relatively inexpensively but also, through the high temperatures generated, will facilitate bonding to a variety of surfaces

  8. Tissue source determines the differentiation potentials of mesenchymal stem cells: a comparative study of human mesenchymal stem cells from bone marrow and adipose tissue.

    Science.gov (United States)

    Xu, Liangliang; Liu, Yamei; Sun, Yuxin; Wang, Bin; Xiong, Yunpu; Lin, Weiping; Wei, Qiushi; Wang, Haibin; He, Wei; Wang, Bin; Li, Gang

    2017-12-06

    Mesenchymal stem cells (MSCs) possess intrinsic regeneration capacity as part of the repair process in response to injury, such as fracture or other tissue injury. Bone marrow and adipose tissue are the major sources of MSCs. However, which cell type is more effective and suitable for cell therapy remains to be answered. The intrinsic molecular mechanism supporting the assertion has also been lacking. Human bone marrow-derived MSCs (BMSCs) and adipose tissue-derived MSCs (ATSCs) were isolated from bone marrow and adipose tissue obtained after total hip arthroplasty. ATSCs and BMSCs were incubated in standard growth medium. Trilineage differentiation including osteogenesis, adipogenesis, and chondrogenesis was performed by addition of relevant induction mediums. The expression levels of trilineage differentiation marker genes were evaluated by quantitative RT-PCR. The methylation status of CpG sites of Runx2, PPARγ, and Sox9 promoters were checked by bisulfite sequencing. In addition, ectopic bone formation and calvarial bone critical defect models were used to evaluate the bone regeneration ability of ATSCs and BMSCs in vivo. The results showed that BMSCs possessed stronger osteogenic and lower adipogenic differentiation potentials compared to ATSCs. There was no significant difference in the chondrogenic differentiation potential. The CpG sites of Runx2 promoter in BMSCs were hypomethylated, while in ATSCs they were hypermethylated. The CpG sites of PPARγ promoter in ATSCs were hypomethylated, while in BMSCs they were hypermethylated. The methylation status of Sox9 promoter in BMSCs was only slightly lower than that in ATSCs. The epigenetic memory obtained from either bone marrow or adipose tissue favored MSC differentiation along an osteoblastic or adipocytic lineage. The methylation status of the main transcription factors controlling MSC fate contributes to the differential differentiation capacities of different source-derived MSCs.

  9. Blood Vessel Formation and Bone Regeneration Potential of the Stromal Vascular Fraction Seeded on a Calcium Phosphate Scaffold in the Human Maxillary Sinus Floor Elevation Model

    Directory of Open Access Journals (Sweden)

    Elisabet Farré-Guasch

    2018-01-01

    Full Text Available Bone substitutes are used as alternatives for autologous bone grafts in patients undergoing maxillary sinus floor elevation (MSFE for dental implant placement. However, bone substitutes lack osteoinductive and angiogenic potential. Addition of adipose stem cells (ASCs may stimulate osteogenesis and osteoinduction, as well as angiogenesis. We aimed to evaluate the vascularization in relation to bone formation potential of the ASC-containing stromal vascular fraction (SVF of adipose tissue, seeded on two types of calcium phosphate carriers, within the human MSFE model, in a phase I study. Autologous SVF was obtained from ten patients and seeded on β-tricalcium phosphate (n = 5 or biphasic calcium phosphate carriers (n = 5, and used for MSFE in a one-step surgical procedure. After six months, biopsies were obtained during dental implant placement, and the quantification of the number of blood vessels was performed using histomorphometric analysis and immunohistochemical stainings for blood vessel markers, i.e., CD34 and alpha-smooth muscle actin. Bone percentages seemed to correlate with blood vessel formation and were higher in study versus control biopsies in the cranial area, in particular in β-tricalcium phosphate-treated patients. This study shows the safety, feasibility, and efficiency of the use of ASCs in the human MSFE, and indicates a pro-angiogenic effect of SVF.

  10. Application of bone scintigrams in total knee replacement (Okayama MK-II type)

    Energy Technology Data Exchange (ETDEWEB)

    Umeda, T.; Inoue, S.; Matsui, N.; Moriya, H. (Chiba Univ. (Japan). School of Medicine)

    1982-02-01

    Eighteen patients with 21 total knee replacements (OKAYAMA MK-II type) were examined by radionuclide imaging in order to assess the prosthetic complaints such as loosening, infection, fracture and lasting pain. The following results and conclusions were obtained. 1) Bone imaging can reveal the condition of the attachment of bone and prosthesis. 2) Diffuse uptake gradually diminished until 18 months after surgery. 3) In front view on bone imaging, tibial uptake corresponded highly with the part of the weight area. 4) In cases of high uptake of posterior femoral component in lateral view, the range of knee flexion was mostly restricted. 5) Long-period persistent local uptake suggested loosening of the prosthesis or fracture of the tibial plateau. 6) Patello-femoral uptake showed no relation to the patellofemoral complaints. Radionuclide bone imaging is considered to represent one of the most valuable diagnostic procedures for assessing the clinical results after total knee replacement.

  11. Application of calcium phosphates and fibronectin as complementary treatment for osteoporotic bone fractures.

    Science.gov (United States)

    Plaza, Javier Quintana; Garzón, Lorena Benito; Gimenez, Beatriz Bravo; Moraleda, Belén Fernández-Montes; Collía, Francisco; Rodríguez-Lorenzo, Luis M

    2016-09-01

    The gradual aging of the population results in increased incidence of osteoporotic bone fractures. In a good quality bone, the fixation with the usual methods is adequate, but not in osteoporotic bone, in which consolidation delays and other complications are common, with failure rates for screws up to 25%. To test fibronectin loaded hydroxyapatite as a complementary treatment for osteoporotic fractures. This study was performed in a vivo model; 42 female osteoporotic adult rabbits 4-5kg (White New Zealand) were used. Two groups (hydroxyapatite and fibronectin loaded hydroxyapatite) and a control group were tested. 3 time points 24h, 48h and 5days were studied. Defects were created in both femurs, in one of them, a cannulated screw (4mm) and a biocompatible material were placed; in the other femur a screw was inserted without supplemented material forming the control group. Osteoporosis was induced from models already known throughout administration of steroids. Samples were analyzed histologically and through imaging (micro Ct). Basal levels of BMD are observed below to normal when compared to other studies (0.25/0.3 instead of 0.4). Global and dependent of time analysis of samples, show no significant differences for samples analyzed. However, an important trend was noted for variables that define the trabecular bone microarchitecture. Indices that define trabecular microarchitecture in the comparative analysis found to have statistical differences (p<0.01). Osteosynthesis in an osteoporotic bone is a challenge for the surgeon, due to a reduced bone mineral density and different bone architecture. The main finding was the verification of the hypothesis that the trabecular bone parameters increases with our augmentation material in weak rabbit bone quality. Also, the histological analyses of samples show an increase of non inflammatory cells in protein samples (OHAp-Fn) from the first 24hours. An early response of rabbit osteroporotic bone to a complementary

  12. Electrically conductive borate-based bioactive glass scaffolds for bone tissue engineering applications.

    Science.gov (United States)

    Turk, Mert; Deliormanlı, Aylin M

    2017-07-01

    In this study, electrically conductive, borate-based, porous 13-93B3 bioactive glass composite scaffolds were prepared using a polymer foam replication technique. For this purpose, a slurry containing 40 vol% glass particles and 0-10 wt% graphene nanoplatelets was prepared by dispersing the particles in ethanol in the presence of ethyl cellulose. Composite scaffolds were subjected to a controlled heat treatment, in air atmosphere, to decompose the foam and sinter the glass particles into a dense network. It was found that the applied heat treatment did not influence the structure of graphene in the glass network. Graphene additions did not negatively affect the mechanical properties and enhanced the electrical conductivity of the glass scaffolds. In X-ray diffraction analysis, the crystalline peak corresponding to hydroxyapatite was observed in all the samples suggesting that all of the samples were bioactive after 30 days of immersion in simulated body fluid. However, Fourier transform infrared spectroscopy analysis and scanning electron microscope observations revealed that hydroxyapatite formation rate decreased with increasing graphene concentration especially for samples treated in simulated body fluid for shorter times. Based on the cytotoxicity assay findings, the MC3T3-E1 cell growth was significantly inhibited by the scaffolds containing higher amount of graphene compared to bare glass scaffolds. Best performance was obtained for 5 wt% graphene which yielded an enhancement of electrical conductivity with moderate cellular response and in vitro hydroxyapatite forming ability. The study revealed that the electrically conductive 13-93B3 graphene scaffolds are promising candidates for bone tissue engineering applications.

  13. [Application of GVF snake model in segmentation of whole body bone SPECT image].

    Science.gov (United States)

    Zhu, Chunmei; Tian, Lianfang; Chen, Ping; Wang, Lifei; Ye, Guangchun; Mao, Zongyuan

    2008-02-01

    Limited by the imaging principle of whole body bone SPECT image, the gray value of bladder area is quite high, which affects the image's brightness, contrast and readability. In the meantime, the similarity between bladder area and focus makes it difficult for some images to be segmented automatically. In this paper, an improved Snake model, GVF Snake, is adopted to automatically segment bladder area, preparing for further processing of whole body bone SPECT images.

  14. Concise review: Bone marrow for the treatment of spinal cord injury: mechanisms and clinical applications.

    OpenAIRE

    Wright, KT; El Masri, W; Osman, A; Chowdhury, J; Johnson, WEB

    2011-01-01

    Transplantation of bone marrow stem cells into spinal cord lesions enhances axonal regeneration and promotes functional recovery in animal studies. There are two types of adult bone marrow stem cell; hematopoietic stem cells (HSCs), and mesenchymal stem cells (MSCs). The mechanisms by which HSCs and MSCs might promote spinal cord repair following transplantation have been extensively investigated. The objective of this review is to discuss these mechanisms; we briefly consider the controversi...

  15. Fabrication and characterization of highly porous barium titanate based scaffold coated by Gel/HA nanocomposite with high piezoelectric coefficient for bone tissue engineering applications.

    Science.gov (United States)

    Ehterami, Arian; Kazemi, Mansure; Nazari, Bahareh; Saraeian, Payam; Azami, Mahmoud

    2018-03-01

    It is well established that the piezoelectric effect plays an important physiological role in bone growth, remodeling and fracture healing. Barium titanate, as a well-known piezoelectric ceramic, is especially an attractive material as a scaffold for bone tissue engineering applications. In this regard, we tried to fabricate a highly porous barium titanate based scaffolds by foam replication method and polarize them by applying an external electric field. In order to enhance the mechanical and biological properties, polarized/non-polarized scaffolds were coated with gelatin and nanostructured HA and characterized for their morphologies, porosities, piezoelectric and mechanical properties. The results showed that the compressive strength and piezoelectric coefficient of porous scaffolds increased with the increase of sintering temperature. After being coated with Gel/HA nanocomposite, the interconnected porous structure and pore size of the scaffolds almost remain unchanged while the Gel/nHA-coated scaffolds exhibited enhanced compressive strength and elastic modulus compared with the uncoated samples. Also, the effect of polarizing and coating of optimal scaffolds on adhesion, viability, and proliferation of the MG63 osteoblast-like cell line was evaluated by scanning electron microscope (SEM) and MTT assay. The cell culture experiments revealed that developed scaffolds had good biocompatibility and cells were able to adhere, proliferate and migrate into pores of the scaffolds. Furthermore, cell density was significantly higher in the coated scaffolds at all tested time-points. These results indicated that highly porous barium titanate scaffolds coated with Gel/HA nanocomposite has great potential in tissue engineering applications for bone tissue repair and regeneration. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Characterization and osteogenic potential of equine muscle tissue- and periosteal tissue-derived mesenchymal stem cells in comparison with bone marrow- and adipose tissue-derived mesenchymal stem cells.

    Science.gov (United States)

    Radtke, Catherine L; Nino-Fong, Rodolfo; Esparza Gonzalez, Blanca P; Stryhn, Henrik; McDuffee, Laurie A

    2013-05-01

    To characterize equine muscle tissue- and periosteal tissue-derived cells as mesenchymal stem cells (MSCs) and assess their proliferation capacity and osteogenic potential in comparison with bone marrow- and adipose tissue-derived MSCs. Tissues from 10 equine cadavers. Cells were isolated from left semitendinosus muscle tissue, periosteal tissue from the distomedial aspect of the right tibia, bone marrow aspirates from the fourth and fifth sternebrae, and adipose tissue from the left subcutaneous region. Mesenchymal stem cells were characterized on the basis of morphology, adherence to plastic, trilineage differentiation, and detection of stem cell surface markers via immunofluorescence and flow cytometry. Mesenchymal stem cells were tested for osteogenic potential with osteocalcin gene expression via real-time PCR assay. Mesenchymal stem cell cultures were counted at 24, 48, 72, and 96 hours to determine tissue-specific MSC proliferative capacity. Equine muscle tissue- and periosteal tissue-derived cells were characterized as MSCs on the basis of spindle-shaped morphology, adherence to plastic, trilineage differentiation, presence of CD44 and CD90 cell surface markers, and nearly complete absence of CD45 and CD34 cell surface markers. Muscle tissue-, periosteal tissue-, and adipose tissue-derived MSCs proliferated significantly faster than did bone marrow-derived MSCs at 72 and 96 hours. Equine muscle and periosteum are sources of MSCs. Equine muscle- and periosteal-derived MSCs have osteogenic potential comparable to that of equine adipose- and bone marrow-derived MSCs, which could make them useful for tissue engineering applications in equine medicine.

  17. The effect of hydroxyapatite addition on the mechanical properties of polyvinyl alcohol/chitosan biomaterials for bone scaffolds application

    Science.gov (United States)

    Ramahdita, Ghiska; Puspita, Debie Maya; Albab, Muh Fadhil; Alfata, Rowi; Sofyan, Nofrijon; Yuwono, Akhmad Herman

    2018-02-01

    The increasing number of bone fracture incident in Indonesia from year to year needs an urgent problem solving of the limited bone substitute which can meet the necessary criteria for that purpose. Motivated by this, therefore, the current study is focusing on the optimization of material properties used as bone scaffold. A biomaterial of polyvinyl alcohol (PVA)/chitosan-hydroxyapatite (HA) composite was successfully made by wet chemistry method, followed by freeze thawing and freeze drying. For comparison purposes, the percentage of HA has been varied from 0, 25 and 40 % (wt/v). The resulting composites were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), compressive test, and swelling behavior. The results showed that the addition of HA up to 40% (wt/v) has yielded a porous structure with an average pore size of 42.39 µm. In addition, the compressive modulus was enhanced from 14 MPa for 0% HA to 143, and 191 MPa for composites with the addition of HA from 25 to 40% (wt/v). The addition of HA has also reduced the swelling ratio from 296% for the sample without HA to 85 and 78 % for sample with addition of HA from 25 to 40 (wt/v), respectively. The obtained results show that PVA/chitosan-HA in this study is potential to be used as scaffold in bone tissue engineering.

  18. The potentiation of Mangifera casturi bark extract on interleukin- 1β and bone morphogenic protein-2 expressions during bone remodeling after tooth extraction

    Directory of Open Access Journals (Sweden)

    Bayu Indra Sukmana

    2017-03-01

    Full Text Available Background: The main oral health problem in Indonesia is the high number of tooth decay. Tooth extraction is the treatment often received by patients who experience tooth decay and the wound caused by alveolar bone resorption. Bark of Mangifera casturi has been studied and proven to contain secondary metabolite which has the ability to increase osteoblast’s activity and suppress osteoclast’s activity. Purpose: The purpose of this study was to analyze interleukin-1 beta (IL-1β and bone morphogenic protein-2 (BMP-2 activities during bone remodeling after Mangifera casturi’s bark extract treatment. Method: This study was laboratory experimental research with randomized post-test only control group design. The Mangifera casturi bark was extracted using 96% ethanol maceration and n-hexane fractionation. This study used 40 male Wistar rats which are divided into 4 groups and the tooth extraction was performed on the rats’ right mandible incisive tooth. The four groups consisted of 6.35%, 12.7%, 25.4% extract treatment group, and a control group. Wistar’s mandibles were decapitated on the 7th and 14th day after extraction. Antibody staining on preparations for the examination of IL-1β and BMP-2 expressions was done using immunohistochemistry. Result: There was a significant difference of IL-1β and BMP-2 expressions in 6,35%, 12,7%, and 25,4% treatment groups compared to control group with p<0.05. Conclusion: Mangifera casturi’s bark extract was able to suppress the IL-1β expression and increase the BMP-2 expression during bone remodeling after tooth extraction.

  19. In vitro and in vivo investigations on bone regeneration potential of laminated hydroxyapatite/gelatin nanocomposite scaffold along with DBM

    International Nuclear Information System (INIS)

    Tavakol, Shima; Ragerdi Kashani, Iraj; Azami, Mahmood; Khoshzaban, Ahad; Tavakol, Behnaz; Kharrazi, Sharmin; Ebrahimi, Somayeh; Rezayat Sorkhabadi, Seyed Mahdi

    2012-01-01

    Bone regeneration ability of a scaffold strongly depends on its structure and the size of its components. In this study, a nanostructured scaffold was designed for bone repair using nano hydroxyapatite (nHA) (8–16 nm × 50–80 nm) and gelatin (GEL) as main components. In vitro investigations of calcium matrix deposition and gene expression of the seeded cells for this scaffold, demineralized bone matrix (DBM), scaffold plus DBM, and the control group were carried out. Bone regeneration in rat calvarium with critical defect size after 1, 4, and 8 weeks post implantation was investigated. The calcium matrix depositions by the osteoblast and RUNX2, ALP, osteonectin, and osteocalcin gene expression in scaffold were more significant than in other groups. Histomorphometry analysis confirmed in vitro results. In vitro and in vivo bone regeneration were least in scaffold plus DBM group. Enhanced effects in scaffold could be attributed to the shape and size of nHA particles and good architecture of the scaffold. Reduction of bone regeneration might be due to tight bonding of BMPs and nHA particles in the third group. Results obtained from this study confirmed that nano-scale size of the main components and the scaffold architecture (pore diameter, interconnectivity pores, etc.) have significant effects on bone regeneration ability of the scaffold and are important parameters in designing a temporary bone substitute.

  20. The pectinases from Sphenophorus levis: Potential for biotechnological applications.

    Science.gov (United States)

    Habrylo, Olivier; Evangelista, Danilo Elton; Castilho, Priscila Vasques; Pelloux, Jérôme; Henrique-Silva, Flávio

    2018-01-31

    Pectinases represent about one fifth of the enzyme worldwide market due their wide range of biotechnological applications. Current commercial pectinases are exclusively obtained from microbial sources, but here we report a pectin methylesterase (Sl-PME) and an endo-polygalacturonase (Sl-EPG) bioprospected from the sugarcane weevil, Sphenophorus levis, which revealed good potential for industrial applications. Sl-PME and Sl-EPG were overexpressed in Pichia pastoris, purified and enzymatically characterized. Sl-EPG presents optimal activity at pH 4-5 and 50 °C, showing that it can be used for juice extraction and clarification. On the other hand, Sl-PME presents optimal activity at pH 6-8 and 40 °C, and thus, suitable for both acidic and alkaline processing, such as coffee and tea fermentation. Sl-EPG shows V max  = 3.23 mM/min, K M  = 2.4 g/L and k cat  = 418.6 s -1 . While Sl-PME shows V max  = 0.14 mM/min, K M  = 4.1 g/L and k cat  = 1.7 s -1 . A PG inhibitor (PGIP2) weakly interfered in the Sl-EPG activity and Sl-PME was not affected by a usual PME inhibitor. Moreover, these enzymes manifested synergistic action towards methylesterified pectin. Here, we propose these enzymes as novel alternative tools for the current commercial pectinases. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Incorporation of poly(ethylene glycol) grafted cellulose nanocrystals in poly(lactic acid) electrospun nanocomposite fibers as potential scaffolds for bone tissue engineering.

    Science.gov (United States)

    Zhang, Chunmei; Salick, Max R; Cordie, Travis M; Ellingham, Tom; Dan, Yi; Turng, Lih-Sheng

    2015-04-01

    Poly(ethylene glycol) (PEG)-grafted cellulose nanocrystals (CNCs) were successfully synthesized and incorporated into poly(lactic acid) (PLA) as a reinforcing filler to produce nanocomposite scaffolds consisting of CNC-g-PEG and PLA using an electrospinning technique. Morphological, thermal, mechanical, and wettability properties as well as preliminary biocompatibility using human mesenchymal stem cells (hMSCs) of PLA/CNC and PLA/CNC-g-PEG nanocomposite scaffolds were characterized and compared. The average diameter of the electrospun nanofibers decreased with increased filler loading level, due to the increased conductivity of the electrospun solutions. DSC results showed that both the glass transition temperature and cold crystallization temperature decreased progressively with higher CNC-g-PEG loading level, suggesting that improved interfacial adhesion between CNCs and PLA was achieved by grafting PEG onto the CNCs. Wettability of the electrospun nanofibers was not affected with the addition of CNCs or CNC-g-PEG and indicating that the fillers tended to stay inside of the fiber matrix under electrical field. The tensile strength of the composite fiber mats was effectively improved by the addition of up to 5% CNC-g-PEG up to 5wt.%. In addition, the cell culture results showed that PLA/CNC-g-PEG composite nanofibers exhibited improved biocompatibility to hMSCs, which revealed the potential application of this nanocomposite as the scaffolds in bone tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. The Chondrogenic Induction Potential for Bone Marrow-Derived Stem Cells between Autologous Platelet-Rich Plasma and Common Chondrogenic Induction Agents: A Preliminary Comparative Study

    Directory of Open Access Journals (Sweden)

    Shan-zheng Wang

    2015-01-01

    Full Text Available The interests in platelet-rich plasma (PRP and their application in stem cell therapy have contributed to a better understanding of the basic biology of the prochondrogenesis effect on bone marrow-derived stem cells (BMSCs. We aimed at comparing the effect of autologous PRP with common chondrogenic induction agents (CCIAs on the chondrogenic differentiation of BMSCs. Rabbit BMSCs were isolated and characterized by flow cytometry and differentiated towards adipocytes and osteoblasts. The chondrogenic response of BMSCs to autologous PRP and CCIAs which included transforming growth factor-β1 (TGF-β1, dexamethasone (DEX, and vitamin C (Vc was examined by cell pellet culture. The isolated BMSCs after two passages highly expressed CD29 and CD44 but minimally expressed CD45. The osteogenic and adipogenic differentiation potentials of the isolated BMSCs were also confirmed. Compared with common CCIAs, autologous PRP significantly upregulated the chondrogenic related gene expression, including Col-2, AGC, and Sox-9. Osteogenic related gene expression, including Col-1 and OCN, was not of statistical significance between these two groups. Thus, our data shows that, compared with common chondrogenic induction agents, autologous PRP can be more effective in promoting the chondrogenesis of BMSCs.

  3. Nanotechnology in the targeted drug delivery for bone diseases and bone regeneration

    Directory of Open Access Journals (Sweden)

    Gu W

    2013-06-01

    Full Text Available Wenyi Gu,1,2 Chengtie Wu,3 Jiezhong Chen,1 Yin Xiao1 1Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia; 2Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia; 3State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, People's Republic of China Abstract: Nanotechnology is a vigorous research area and one of its important applications is in biomedical sciences. Among biomedical applications, targeted drug delivery is one of the most extensively studied subjects. Nanostructured particles and scaffolds have been widely studied for increasing treatment efficacy and specificity of present treatment approaches. Similarly, this technique has been used for treating bone diseases including bone regeneration. In this review, we have summarized and highlighted the recent advancement of nanostructured particles and scaffolds for the treatment of cancer bone metastasis, osteosarcoma, bone infections and inflammatory diseases, osteoarthritis, as well as for bone regeneration. Nanoparticles used to deliver deoxyribonucleic acid and ribonucleic acid molecules to specific bone sites for gene therapies are also included. The investigation of the implications of nanoparticles in bone diseases have just begun, and has already shown some promising potential. Further studies have to be conducted, aimed specifically at assessing targeted delivery and bioactive scaffolds to further improve their efficacy before they can be used clinically. Keywords: nanoparticles, nanostructured scaffold, cancer bone metastasis, bone diseases, target drug delivery, bone regeneration

  4. Configuration and technology implications of potential nuclear hydrogen system applications.

    Energy Technology Data Exchange (ETDEWEB)

    Conzelmann, G.; Petri, M.; Forsberg, C.; Yildiz, B.; ORNL

    2005-11-05

    Nuclear technologies have important distinctions and potential advantages for large-scale generation of hydrogen for U.S. energy services. Nuclear hydrogen requires no imported fossil fuels, results in lower greenhouse-gas emissions and other pollutants, lends itself to large-scale production, and is sustainable. The technical uncertainties in nuclear hydrogen processes and the reactor technologies needed to enable these processes, as well waste, proliferation, and economic issues must be successfully addressed before nuclear energy can be a major contributor to the nation's energy future. In order to address technical issues in the time frame needed to provide optimized hydrogen production choices, the Nuclear Hydrogen Initiative (NHI) must examine a wide range of new technologies, make the best use of research funding, and make early decisions on which technology options to pursue. For these reasons, it is important that system integration studies be performed to help guide the decisions made in the NHI. In framing the scope of system integration analyses, there is a hierarchy of questions that should be addressed: What hydrogen markets will exist and what are their characteristics? Which markets are most consistent with nuclear hydrogen? What nuclear power and production process configurations are optimal? What requirements are placed on the nuclear hydrogen system? The intent of the NHI system studies is to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This work couples with system studies sponsored by DOE-EE and other agencies that provide a basis for evaluating and selecting future hydrogen production technologies. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options

  5. Marine Bioactives: Pharmacological Properties and Potential Applications against Inflammatory Diseases

    Science.gov (United States)

    D’Orazio, Nicolantonio; Gammone, Maria Alessandra; Gemello, Eugenio; De Girolamo, Massimo; Cusenza, Salvatore; Riccioni, Graziano

    2012-01-01

    Inflammation is a hot topic in medical research, because it plays a key role in inflammatory diseases: rheumatoid arthritis (RA) and other forms of arthritis, diabetes, heart diseases, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, even cancer and many others. Over the past few decades, it was realized that the process of inflammation is virtually the same in different disorders, and a better understanding of inflammation may lead to better treatments for numerous diseases. Inflammation is the activation of the immune system in response to infection, irritation, or injury, with an influx of white blood cells, redness, heat, swelling, pain, and dysfunction of the organs involved. Although the pathophysiological basis of these conditions is not yet fully understood, reactive oxygen species (ROS) have often been implicated in their pathogenesis. In fact, in inflammatory diseases the antioxidant defense system is compromised, as evidenced by increased markers of oxidative stress, and decreased levels of protective antioxidant enzymes in patients with rheumatoid arthritis (RA). An enriched diet containing antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic substances, has been suggested to improve symptoms by reducing disease-related oxidative stress. In this respect, the marine world represents a largely untapped reserve of bioactive ingredients, and considerable potential exists for exploitation of these bioactives as functional food ingredients. Substances such as n-3 oils, carotenoids, vitamins, minerals and peptides provide a myriad of health benefits, including reduction of cardiovascular diseases, anticarcinogenic and anti-inflammatory activities. New marine bioactives are recently gaining attention, since they could be helpful in combating chronic inflammatory degenerative conditions. The aim of this review is to examine the published studies concerning the potential pharmacological properties and

  6. Bone Tissue Engineering: Recent Advances and Challenges

    Science.gov (United States)

    Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

    2013-01-01

    The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regen