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Sample records for altered bone material

  1. HBM Mice Have Altered Bone Matrix Composition and Improved Material Toughness.

    Science.gov (United States)

    Ross, Ryan D; Mashiatulla, Maleeha; Acerbo, Alvin S; Almer, Jonathan D; Miller, Lisa M; Johnson, Mark L; Sumner, D Rick

    2016-10-01

    The G171V mutation in the low-density lipoprotein receptor-related protein 5 (LRP5) leads to a high bone mass (HBM) phenotype. Studies using HBM transgenic mouse models have consistently found increased bone mass and whole-bone strength, but little attention has been paid to the composition of the bone matrix. The current study sought to determine if the cortical bone matrix composition differs in HBM and wild-type mice and to determine how much of the variance in bone material properties is explained by variance in matrix composition. Consistent with previous studies, HBM mice had greater cortical area, moment of inertia, ultimate force, bending stiffness, and energy to failure than wild-type animals. The increased energy to failure was primarily caused by a large increase in post-yield behavior, with no difference in pre-yield behavior. The HBM mice had increased mineral-to-matrix and collagen cross-link ratios, and decreased crystallinity, carbonate, and acid phosphate substitution as measured by Fourier transform infrared microspectroscopy, but no differences in crystal length, intra-fibular strains, and mineral spacing compared to wild-type controls, as measured by X-ray scattering. The largest between genotype difference in material properties was a twofold increase in the modulus of toughness in HBM mice. Step-wise regression analyses showed that the specific matrix compositional parameters most closely associated with material properties varied between the wild-type and HBM genotypes. Although the mechanisms controlling the paradoxical combination of more mineralized yet tougher bone in HBM mice remain to be fully explained, the findings suggest that LRP5 represents a target to not only build bone mass but also to improve bone quality.

  2. Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral

    Science.gov (United States)

    Paschalis, E.P.; Tatakis, D.N.; Robins, S.; Fratzl, P.; Manjubala, I.; Zoehrer, R.; Gamsjaeger, S.; Buchinger, B.; Roschger, A.; Phipps, R.; Boskey, A.L.; Dall'Ara, E.; Varga, P.; Zysset, P.; Klaushofer, K.; Roschger, P.

    2011-01-01

    In the present study a rat animal model of lathyrism was employed to decipher whether anatomically confined alterations in collagen cross-links are sufficient to influence the mechanical properties of whole bone. Animal experiments were performed under an ethics committee approved protocol. Sixty-four female (47 day old) rats of equivalent weights were divided into four groups (16 per group): Controls were fed a semi-synthetic diet containing 0.6% calcium and 0.6% phosphorus for 2 or 4 weeks and β-APN treated animals were fed additionally with β-aminopropionitrile (0.1% dry weight). At the end of this period the rats in the four groups were sacrificed, and L2–L6 vertebra were collected. Collagen cross-links were determined by both biochemical and spectroscopic (Fourier transform infrared imaging (FTIRI)) analyses. Mineral content and distribution (BMDD) were determined by quantitative backscattered electron imaging (qBEI), and mineral maturity/crystallinity by FTIRI techniques. Micro-CT was used to describe the architectural properties. Mechanical performance of whole bone as well as of bone matrix material was tested by vertebral compression tests and by nano-indentation, respectively. The data of the present study indicate that β-APN treatment changed whole vertebra properties compared to non-treated rats, including collagen cross-links pattern, trabecular bone volume to tissue ratio and trabecular thickness, which were all decreased (p < 0.05). Further, compression tests revealed a significant negative impact of β-APN treatment on maximal force to failure and energy to failure, while stiffness was not influenced. Bone mineral density distribution (BMDD) was not altered either. At the material level, β-APN treated rats exhibited increased Pyd/Divalent cross-link ratios in areas confined to a newly formed bone. Moreover, nano-indentation experiments showed that the E-modulus and hardness were reduced only in newly formed bone areas under the influence

  3. Examining the diagenetic alteration of human bone material from a range of archaeological burial sites using nuclear microscopy

    Science.gov (United States)

    Elliott, T. A.; Grime, G. W.

    1993-05-01

    The inorganic analysis of archaeological bone material can potentially provide a wealth of information about the chronology, diet and palaeoenvironment of past populations: for example, strontium and uranium levels are used in palaeodietary and dating studies, respectively. However, the extent to which the chemical composition of bone is subject to diagenetic change during burial is open to controversy due, in part, to differences in analytical technique, bone types and burial conditions. To investigate this problem, archaeological human bone material from a number of different geological environments including Pompeii and a 12th century British ecclesiastical site, together with material from two seawater burials (The "Mary Rose" and a 6th century Mediterranean wreck) have been studied using the nuclear microprobe facility at the University of Oxford. Results using microbeam PIXE show that bone is subject to contamination from a wide range of trace elements depending on the burial conditions. Elemental maps are presented to demonstrate the distribution of trace element accumulation under different burial conditions, and the significance of this work to future trace element studies is discussed.

  4. Bone Material Properties in Osteogenesis Imperfecta.

    Science.gov (United States)

    Bishop, Nick

    2016-04-01

    Osteogenesis imperfecta entrains changes at every level in bone tissue, from the disorganization of the collagen molecules and mineral platelets within and between collagen fibrils to the macroarchitecture of the whole skeleton. Investigations using an array of sophisticated instruments at multiple scale levels have now determined many aspects of the effect of the disease on the material properties of bone tissue. The brittle nature of bone in osteogenesis imperfecta reflects both increased bone mineralization density-the quantity of mineral in relation to the quantity of matrix within a specific bone volume-and altered matrix-matrix and matrix mineral interactions. Contributions to fracture resistance at multiple scale lengths are discussed, comparing normal and brittle bone. Integrating the available information provides both a better understanding of the effect of current approaches to treatment-largely improved architecture and possibly some macroscale toughening-and indicates potential opportunities for alternative strategies that can influence fracture resistance at longer-length scales.

  5. Occlusal effects on longitudinal bone alterations of the temporomandibular joint.

    Science.gov (United States)

    Zhang, J; Jiao, K; Zhang, M; Zhou, T; Liu, X-D; Yu, S-B; Lu, L; Jing, L; Yang, T; Zhang, Y; Chen, D; Wang, M-Q

    2013-03-01

    The pathological changes of subchondral bone during osteoarthritis (OA) development in the temporomandibular joint (TMJ) are poorly understood. In the present study, we investigated the longitudinal alterations of subchondral bone using a rat TMJ-OA model developed in our laboratory. Changes in bone mass were examined by micro-CT, and changes in osteoblast and osteoclast activities were analyzed by real-time PCR, immunohistochemistry, and TRAP staining. Subchondral bone loss was detected from 8 weeks after dental occlusion alteration and reached the maximum at 12 weeks, followed by a repair phase until 32 weeks. Although bone mass increased at late stages, poor mechanical structure and lower bone mineral density (BMD) were found in these rats. The numbers of TRAP-positive cells were increased at 12 weeks, while the numbers of osteocalcin-expressing cells were increased at both 12 and 32 weeks. Levels of mRNA expression of TRAP and cathepsin K were increased at 12 weeks, while levels of ALP and osteocalcin were increased at both 12 and 32 weeks. These findings demonstrated that there is an active bone remodeling in subchondral bone in TMJs in response to alteration in occlusion, although new bone was formed with lower BMD and poor mechanical properties.

  6. Exploring the Bone Proteome to Help Explain Altered Bone Remodeling and Preservation of Bone Architecture and Strength in Hibernating Marmots.

    Science.gov (United States)

    Doherty, Alison H; Roteliuk, Danielle M; Gookin, Sara E; McGrew, Ashley K; Broccardo, Carolyn J; Condon, Keith W; Prenni, Jessica E; Wojda, Samantha J; Florant, Gregory L; Donahue, Seth W

    2016-01-01

    Periods of physical inactivity increase bone resorption and cause bone loss and increased fracture risk. However, hibernating bears, marmots, and woodchucks maintain bone structure and strength, despite being physically inactive for prolonged periods annually. We tested the hypothesis that bone turnover rates would decrease and bone structural and mechanical properties would be preserved in hibernating marmots (Marmota flaviventris). Femurs and tibias were collected from marmots during hibernation and in the summer following hibernation. Bone remodeling was significantly altered in cortical and trabecular bone during hibernation with suppressed formation and no change in resorption, unlike the increased bone resorption that occurs during disuse in humans and other animals. Trabecular bone architecture and cortical bone geometrical and mechanical properties were not different between hibernating and active marmots, but bone marrow adiposity was significantly greater in hibernators. Of the 506 proteins identified in marmot bone, 40 were significantly different in abundance between active and hibernating marmots. Monoaglycerol lipase, which plays an important role in fatty acid metabolism and the endocannabinoid system, was 98-fold higher in hibernating marmots compared with summer marmots and may play a role in regulating the changes in bone and fat metabolism that occur during hibernation.

  7. Dried plum's unique capacity to reverse bone loss and alter bone metabolism in postmenopausal osteoporosis model.

    Science.gov (United States)

    Rendina, Elizabeth; Hembree, Kelsey D; Davis, McKale R; Marlow, Denver; Clarke, Stephen L; Halloran, Bernard P; Lucas, Edralin A; Smith, Brenda J

    2013-01-01

    Interest in dried plum has increased over the past decade due to its promise in restoring bone and preventing bone loss in animal models of osteoporosis. This study compared the effects of dried plum on bone to other dried fruits and further explored the potential mechanisms of action through which dried plum may exert its osteoprotective effects. Adult osteopenic ovariectomized (OVX) C57BL/6 mice were fed either a control diet or a diet supplemented with 25% (w/w) dried plum, apple, apricot, grape or mango for 8 weeks. Whole body and spine bone mineral density improved in mice consuming the dried plum, apricot and grape diets compared to the OVX control mice, but dried plum was the only fruit to have an anabolic effect on trabecular bone in the vertebra and prevent bone loss in the tibia. Restoration of biomechanical properties occurred in conjunction with the changes in trabecular bone in the spine. Compared to other dried fruits in this study, dried plum was unique in its ability to down-regulate osteoclast differentiation coincident with up-regulating osteoblast and glutathione (GPx) activity. These alterations in bone metabolism and antioxidant status compared to other dried fruits provide insight into dried plum's unique effects on bone.

  8. Multifunctional materials for bone cancer treatment

    Directory of Open Access Journals (Sweden)

    Marques C

    2014-05-01

    Full Text Available Catarina Marques,1 José MF Ferreira,1 Ecaterina Andronescu,2 Denisa Ficai,2 Maria Sonmez,3 Anton Ficai21Department of Materials and Ceramics Engineering, Centre for Research in Ceramics and Composite Materials, University of Aveiro, Aveiro, Portugal; 2Faculty of Applied Chemistry and Material Science, University Politehnica of Bucharest, Bucharest, Romania; 3National Research and Development Institute for Textiles and Leather, Bucharest, RomaniaAbstract: The purpose of this review is to present the most recent findings in bone tissue engineering. Special attention is given to multifunctional materials based on collagen and collagen–hydroxyapatite composites used for skin and bone cancer treatments. The multifunctionality of these materials was obtained by adding to the base regenerative grafts proper components, such as ferrites (magnetite being the most important representative, cytostatics (cisplatin, carboplatin, vincristine, methotrexate, paclitaxel, doxorubicin, silver nanoparticles, antibiotics (anthracyclines, geldanamycin, and/or analgesics (ibuprofen, fentanyl. The suitability of complex systems for the intended applications was systematically analyzed. The developmental possibilities of multifunctional materials with regenerative and curative roles (antitumoral as well as pain management in the field of skin and bone cancer treatment are discussed. It is worth mentioning that better materials are likely to be developed by combining conventional and unconventional experimental strategies.Keywords: bone graft, cancer, collagen, magnetite, cytostatics, silver

  9. The materials used in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Tereshchenko, V. P., E-mail: tervp@ngs.ru; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M. [Novosibirsk Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan, Novosibirsk (Russian Federation)

    2015-11-17

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.

  10. Bone mass and bone quality are altered by hypoactivity in the chicken.

    Directory of Open Access Journals (Sweden)

    Eric Aguado

    Full Text Available Disuse induces a rapid bone loss in adults; sedentarity is now recognized as a risk factor for osteoporosis. Hypoactivity or confinement also decrease bone mass in adults but their effects are largely unknown and only few animal models have been described. We have used 10 chickens of the rapidly growing strain 857K bred in a large enclosure (FREE group; 10 others were confined in small cages with little space to move around (HYPO group. They were sacrificed at 53 days and femurs and tibias were evaluated by texture analysis, dual energy X-ray densitometry, microcomputed tomography (microCT and histomorphometry. Hypoactivity had no effect on the length and diameter of the bones. Bone mineral density (BMD, microCT (trabecular bone volume and trabecular microarchitecture and texture analysis were always found significantly reduced in the animals of the HYPO group. BMD was reduced at both femur and tibia diaphysises; BMD of the metaphysis was significantly reduced in the femur but not in the tibia. An increase in osteoid volume and surfaces was noted in the HYPO group. However, there was no alteration of the mineral phase as the osteoid thickness did not differ from control animals. Bone loss was much more pronounced at the lower femur metaphysis than at the upper metaphysis of the tibia. At the tibia, only microarchitectural changes of trabecular bone could be evidenced. The confined chicken represents a new method for the study of hypodynamia since these animals do not have surgical lesions.

  11. 21 CFR 872.3930 - Bone grafting material.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification... “Class II Special Controls Guidance Document: Dental Bone Grafting Material Devices.” (See § 872.1(e) for... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone grafting material. 872.3930 Section...

  12. New insights to the role of aryl hydrocarbon receptor in bone phenotype and in dioxin-induced modulation of bone microarchitecture and material properties

    Energy Technology Data Exchange (ETDEWEB)

    Herlin, Maria, E-mail: maria.herlin@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden); Finnilä, Mikko A.J., E-mail: mikko.finnila@oulu.fi [Department of Medical Technology, Institute of Biomedicine, University of Oulu, Oulu (Finland); Department of Anatomy and Cell Biology, Institute of Biomedicine, University of Oulu, Oulu (Finland); Zioupos, Peter, E-mail: p.zioupos@cranfield.ac.uk [Biomechanics Laboratories, Department of Engineering and Applied Science, Cranfield University, Shrivenham SN6 8LA (United Kingdom); Aula, Antti, E-mail: antti.aula@gmail.com [Department of Medical Physics, Imaging Centre, Tampere University Hospital, Tampere (Finland); Department of Biomedical Engineering, Tampere University of Technology, Tampere (Finland); Risteli, Juha, E-mail: juha.risteli@ppshp.fi [Department of Clinical Chemistry, Oulu University Hospital, Oulu (Finland); Miettinen, Hanna M., E-mail: hanna.miettinen@crl.com [Department of Environmental Health, National Institute for Health and Welfare, Kuopio (Finland); Jämsä, Timo, E-mail: timo.jamsa@oulu.fi [Department of Medical Technology, Institute of Biomedicine, University of Oulu, Oulu (Finland); Department of Diagnostic Radiology, Oulu University Hospital, Oulu (Finland); Tuukkanen, Juha, E-mail: juha.tuukkanen@oulu.fi [Department of Anatomy and Cell Biology, Institute of Biomedicine, University of Oulu, Oulu (Finland); Korkalainen, Merja, E-mail: merja.korkalainen@thl.fi [Department of Environmental Health, National Institute for Health and Welfare, Kuopio (Finland); Håkansson, Helen, E-mail: Helen.Hakansson@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden); Viluksela, Matti, E-mail: matti.viluksela@thl.fi [Department of Environmental Health, National Institute for Health and Welfare, Kuopio (Finland); Department of Environmental Science, University of Eastern Finland, Kuopio (Finland)

    2013-11-15

    Bone is a target for high affinity aryl hydrocarbon receptor (AHR) ligands, such as dioxins. Although bone morphology, mineral density and strength are sensitive endpoints of dioxin toxicity, less is known about effects on bone microarchitecture and material properties. This study characterizes TCDD-induced modulations of bone tissue, and the role of AHR in dioxin-induced bone toxicity and for normal bone phenotype. Six AHR-knockout (Ahr{sup −/−}) and wild-type (Ahr{sup +/+}) mice of both genders were exposed to TCDD weekly for 10 weeks, at a total dose of 200 μg/kg bw. Bones were examined with micro-computed tomography, nanoindentation and biomechanical testing. Serum levels of bone remodeling markers were analyzed, and the expression of genes related to osteogenic differentiation was profiled using PCR array. In Ahr{sup +/+} mice, TCDD-exposure resulted in harder bone matrix, thinner and more porous cortical bone, and a more compact trabecular bone compartment. Bone remodeling markers and altered expression of a number of osteogenesis related genes indicated imbalanced bone remodeling. Untreated Ahr{sup −/−} mice displayed a slightly modified bone phenotype as compared with untreated Ahr{sup +/+} mice, while TCDD exposure caused only a few changes in bones of Ahr{sup −/−} mice. Part of the effects of both TCDD-exposure and AHR-deficiency were gender dependent. In conclusion, exposure of adult mice to TCDD resulted in harder bone matrix, thinner cortical bone, mechanically weaker bones and most notably, increased trabecular bone volume fraction in Ahr{sup +/+} mice. AHR is involved in bone development of a normal bone phenotype, and is crucial for manifestation of TCDD-induced bone alterations. - Highlights: • TCDD disrupts bone remodeling resulting in altered cortical and trabecular bone. • In trabecular bone an anabolic effect is observed. • Cortical bone is thinner, more porous, harder, stiffer and mechanically weaker. • AHR ablation

  13. Cellular compatibility of improved scaffold material with deproteinized heterogeneous bone

    Institute of Scientific and Technical Information of China (English)

    LIU Lei; PEI Fu-xing; ZHOU Zong-ke; LI Qi-hong

    2007-01-01

    Objective:To study cellular compatibility of improved scaffold material with deproteinized heterogeneous bone and provide experimental basis on choosing the scaffold material in bone tissue engineering.Methods: Bone marrow stromal cells (BMSC) were co-cultured with heterogeneous deproteinized bone in vitro. The contrast phase microscope, scanning electron microscope, MTT assay, flow cytometry were performed and the BGP content and ALP activities were detected in order to observe the cell growth, adhesion in the material, cell cycle and cell viability.Results: The scaffold material of deproteinized heterogeneous bone had no inhibitory effect on cellular proliferation, differentiation and secretion function of BMSCs.Conclusions: The established heterogeneous deproteinized bone has good biocompatibility with BMSCs and is a potentially ideal scaffold material for bone tissue engineering.

  14. Biodegradable Materials for Bone Repairs: A Review

    Institute of Scientific and Technical Information of China (English)

    Lili Tan; Xiaoming Yu; Peng Wan; Ke Yang

    2013-01-01

    With attractive research and development of biomaterials,more and more opportunities have been brought to the treatments of human tissue repairs.The implant is usually no need to exist in the body accompanied with the recovery or regeneration of the tissue lesions,and the long-term effect of exotic substance to human body should be reduced as lower as possible.For this purpose,biodegradable materials,including polymers,magnesium alloys and ceramics,have attracted much attention for medical applications due to their biodegradable characters in body environment.This paper in turn introduces these three different types of widely studied biodegradable materials as well as their advantages as implants in applications for bone repairs.Relevant history and research progresses are summarized.

  15. Evaluation of bone response to synthetic bone grafting material treated with argon-based atmospheric pressure plasma

    Energy Technology Data Exchange (ETDEWEB)

    Beutel, Bryan G., E-mail: bryanbeutel@gmail.com; Danna, Natalie R.; Gangolli, Riddhi; Granato, Rodrigo; Manne, Lakshmiprada; Tovar, Nick; Coelho, Paulo G.

    2014-12-01

    Bone graft materials are utilized to stimulate healing of bone defects or enhance osseointegration of implants. In order to augment these capabilities, various surface modification techniques, including atmospheric pressure plasma (APP) surface treatment, have been developed. This in vivo study sought to assess the effect of APP surface treatment on degradation and osseointegration of Synthograft™, a beta-tricalcium phosphate (β-TCP) synthetic bone graft. The experimental (APP-treated) grafts were subjected to APP treatment with argon for a period of 60 s. Physicochemical characterization was performed by environmental scanning electron microscopy, surface energy (SE), and x-ray photoelectron spectroscopy analyses both before and after APP treatment. Two APP-treated and two untreated grafts were surgically implanted into four critical-size calvarial defects in each of ten New Zealand white rabbits. The defect samples were explanted after four weeks, underwent histological analysis, and the percentages of bone, soft tissue, and remaining graft material were quantified by image thresholding. Material characterization showed no differences in particle surface morphology and that the APP-treated group presented significantly higher SE along with higher amounts of the base material chemical elements on it surface. Review of defect composition showed that APP treatment did not increase bone formation or reduce the amount of soft tissue filling the defect when compared to untreated material. Histologic cross-sections demonstrated osteoblastic cell lines, osteoid deposition, and neovascularization in both groups. Ultimately, argon-based APP treatment did not enhance the osseointegration or degradation of the β-TCP graft. Future investigations should evaluate the utility of gases other than argon to enhance osseointegration through APP treatment. - Highlights: • Degradation/osseointegration of bone graft treated with argon-based APP is studied. • APP treatment did

  16. Bone strength and material properties of the glenoid

    DEFF Research Database (Denmark)

    Frich, Lars Henrik; Jensen, N.C.; Odgaard, A.;

    1997-01-01

    The quality of the glenoid bone is important to a successful total shoulder replacement. Finite element models have been used to model the response of the glenoid bone to an implanted prosthesis. Because very little is known about the bone strength and the material properties at the glenoid, thes...

  17. Usefulness of a bioengineered oral mucosa model for preventing palate bone alterations in rabbits with a mucoperiostial defect.

    Science.gov (United States)

    Fernández-Valadés-Gámez, Ricardo; Garzón, Ingrid; Liceras-Liceras, Esther; España-López, Antonio; Carriel, Víctor; Martin-Piedra, Miguel-Ángel; Muñoz-Miguelsanz, María-Ángeles; Sánchez-Quevedo, Maria-Carmen; Alaminos, Miguel; Fernández-Valadés, Ricardo

    2016-02-19

    The use of mucoperiostial flaps during cleft palate surgery is associated with altered palatal bone growth and development. We analyzed the potential usefulness of a bioengineered oral mucosa in an in vivo model of cleft palate. First, a 4 mm palate defect was created in one side of the palate oral mucosa of 3 week-old New Zealand rabbits, and a complete autologous bioengineered oral mucosa (BOM) or acellular fibrin-agarose scaffold (AS) was implanted. No material was implanted in the negative controls (NC), and positive controls were not subjected to palatal defect (PC). Animals were allowed to grow for 6 months and the results were analyzed morphologically (palate mucosa and bone size) and histologically. Results show that palatal mucosa and bone growth and development were significantly altered in NC and AS animals, whereas BOM animals had similar results to PC and the bioengineered oral mucosa was properly integrated in the host palate. The amount and compaction of collagen fibers was similar between BOM and PC, and both groups of animals had comparable contents of proteoglycans and glycoproteins at the palate bone. No differences were found for decorin, osteocalcin and BMP2. The use of bioengineered oral mucosa substitutes is able to improve palate growth and maturation by preventing the alterations found in animals with denuded palate bone. These results support the potential clinical usefulness of BOM substitutes for the treatment of patients with cleft palate and other conditions in which palate mucosa grafts are necessary with consequent bone denudation.

  18. Tungsten Promotes Sex-Specific Adipogenesis in the Bone by Altering Differentiation of Bone Marrow-Resident Mesenchymal Stromal Cells.

    Science.gov (United States)

    Bolt, Alicia M; Grant, Michael P; Wu, Ting Hua; Flores Molina, Manuel; Plourde, Dany; Kelly, Alexander D R; Negro Silva, Luis Fernando; Lemaire, Maryse; Schlezinger, Jennifer J; Mwale, Fackson; Mann, Koren K

    2016-04-01

    Tungsten is a naturally occurring metal that increasingly is being incorporated into industrial goods and medical devices, and is recognized as an emerging contaminant. Tungsten preferentially and rapidly accumulates in murine bone in a concentration-dependent manner; however the effect of tungsten deposition on bone biology is unknown. Other metals alter bone homeostasis by targeting bone marrow-derived mesenchymal stromal cell (MSC) differentiation, thus, we investigated the effects of tungsten on MSCsin vitroandin vivoIn vitro, tungsten shifted the balance of MSC differentiation by enhancing rosiglitazone-induced adipogenesis, which correlated with an increase in adipocyte content in the bone of tungsten-exposed, young, male mice. Conversely, tungsten inhibited osteogenesis of MSCsin vitro; however, we found no evidence that tungsten inhibited osteogenesisin vivo Interestingly, two factors known to influence adipogenesis are sex and age of mice. Both female and older mice have enhanced adipogenesis. We extended our study and exposed young female and adult (9-month) male and female mice to tungsten for 4 weeks. Although tungsten accumulated to a similar extent in young female mice, it did not promote adipogenesis. Interestingly, tungsten did not accumulate in the bone of older mice; it was undetectable in adult male mice, and just above the limit of detect in adult female mice. Surprisingly, tungsten enhanced adipogenesis in adult female mice. In summary, we found that tungsten alters bone homeostasis by altering differentiation of MSCs, which could have significant implications for bone quality, but is highly dependent upon sex and age.

  19. Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis.

    Science.gov (United States)

    Jafari, Abbas; Qanie, Diyako; Andersen, Thomas L; Zhang, Yuxi; Chen, Li; Postert, Benno; Parsons, Stuart; Ditzel, Nicholas; Khosla, Sundeep; Johansen, Harald Thidemann; Kjærsgaard-Andersen, Per; Delaisse, Jean-Marie; Abdallah, Basem M; Hesselson, Daniel; Solberg, Rigmor; Kassem, Moustapha

    2017-02-14

    Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells and that its expression level and cellular localization are altered in postmenopausal osteoporotic patients. As shown by genetic and pharmacological manipulation, legumain inhibited osteoblast (OB) differentiation and in vivo bone formation through degradation of the bone matrix protein fibronectin. In addition, genetic ablation or pharmacological inhibition of legumain activity led to precocious OB differentiation and increased vertebral mineralization in zebrafish. Finally, we show that localized increased expression of legumain in bone marrow adipocytes was inversely correlated with adjacent trabecular bone mass in a cohort of patients with postmenopausal osteoporosis. Our data suggest that altered proteolytic activity of legumain in the bone microenvironment contributes to decreased bone mass in postmenopausal osteoporosis.

  20. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure on bone material properties.

    Science.gov (United States)

    Finnilä, Mikko A J; Zioupos, Peter; Herlin, Maria; Miettinen, Hanna M; Simanainen, Ulla; Håkansson, Helen; Tuukkanen, Juha; Viluksela, Matti; Jämsä, Timo

    2010-04-19

    Dioxins are known to decrease bone strength, architecture and density. However, their detailed effects on bone material properties are unknown. Here we used nanoindentation methods to characterize the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on nanomechanical behaviour of bone matrix. Pregnant rats were treated with a single intragastric dose of TCDD (1 microg/kg) or vehicle on gestational day 11. Tibias of female offspring were sampled on postnatal day (PND) 35 or 70, scanned at mid-diaphysis with pQCT, and evaluated by three-point bending and nanoindentation. TCDD treatment decreased bone mineralization (p<0.05), tibial length (p<0.01), cross-sectional geometry (p<0.05) and bending strength (p<0.05). Controls showed normal maturation pattern between PND 35 and 70 with decreased plasticity by 5.3% and increased dynamic hardness, storage and complex moduli by 26%, 13% and 12% respectively (p<0.05), while similar maturation was not observed in TCDD-exposed pups. In conclusion, for the first time, we demonstrate retardation of bone matrix maturation process in TCDD-exposed animals. In addition, the study confirms that developmental TCDD exposure has adverse effects on bone size, strength and mineralization. The current results in conjunction with macromechanical behaviour suggest that reduced bone strength caused by TCDD is more associated with the mineralization and altered geometry of bones than with changes at the bone matrix level.

  1. Bone alterations by stress in athletes. Schaedigung des Knochens durch Ueberlastung bei Leistungssportlern

    Energy Technology Data Exchange (ETDEWEB)

    Doege, H. (Bezirkskrankenhaus ' Friedrich Wolf' , Abt. fuer Nuklearmedizin, Chemnitz (Germany))

    1990-01-01

    This report describes our experiences with the bone imaging in athletes. We studied 10 athletes and 10 other patients with spondylolisthesis of the lumbar spine and 16 athletes with suspicion of alterations of extremities. An increased uptake of this radiopharmaceutical was detected in six of 10 athletes with spondylolisthesis caused probably by stress fracture. Bone scans were negative in seven of 16 athletes with suspicion of lesion of extremities. In the remaining 9 patients scans were abnormal and showed periosteal injuries, epiphyseal alteration, joint abnormalities, tibial stress fractures and couvert fracture. It was also abnormal in bone injuries not evident in radiography. (orig.).

  2. Diet-induced Obesity Alters Bone Remodeling Leading to Decreased Femoral Trabecular Bone Mass in Mice

    Science.gov (United States)

    Body mass derived from an obesity condition may be detrimental to bone health but the mechanism is unknown. This study was to examine changes in bone structure and serum cytokines related to bone metabolism in obese mice induced by a high-fat diet(HFD). Mice fed the HFD were obese and had higher ser...

  3. 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

  4. Gender- and region-specific alterations in bone metabolism in Scarb1-null female mice.

    Science.gov (United States)

    Martineau, Corine; Martin-Falstrault, Louise; Brissette, Louise; Moreau, Robert

    2014-08-01

    A positive correlation between plasma levels of HDL and bone mass has been reported by epidemiological studies. As scavenger receptor class B, type I (SR-BI), the gene product of Scarb1, is known to regulate HDL metabolism, we recently characterized bone metabolism in Scarb1-null mice. These mice display high femoral bone mass associated with enhanced bone formation. As gender differences have been reported in HDL metabolism and SR-BI function, we investigated gender-specific bone alterations in Scarb1-null mice by microtomography and histology. We found 16% greater relative bone volume and 39% higher bone formation rate in the vertebrae from 2-month-old Scarb1-null females. No such alteration was seen in males, indicating gender- and region-specific differences in skeletal phenotype. Total and HDL-associated cholesterol levels, as well as ACTH plasma levels, were increased in both Scarb1-null genders, the latter being concurrent to impaired corticosterone response to fasting. Plasma levels of estradiol did not differ between null and WT females, suggesting that the estrogen metabolism alteration is not relevant to the higher vertebral bone mass in female Scarb1-null mice. Constitutively, high plasma levels of leptin along with 2.5-fold increase in its expression in white adipose tissue were measured in female Scarb1-null mice only. In vitro exposure of bone marrow stromal cells to ACTH and leptin promoted osteoblast differentiation as evidenced by increased gene expression of osterix and collagen type I alpha. Our results suggest that hyperleptinemia may account for the gender-specific high bone mass seen in the vertebrae of female Scarb1-null mice.

  5. Nano-material aspects of shock absorption in bone joints.

    Science.gov (United States)

    Tributsch, H; Copf, F; Copf, P; Hindenlang, U; Niethard, F U; Schneider, R

    2010-01-01

    This theoretical study is based on a nano-technological evaluation of the effect of pressure on the composite bone fine structure. It turned out, that the well known macroscopic mechano-elastic performance of bones in combination with muscles and tendons is just one functional aspect which is critically supported by additional micro- and nano- shock damping technology aimed at minimising local bone material damage within the joints and supporting spongy bone material. The identified mechanisms comprise essentially three phenomena localised within the three-dimensional spongy structure with channels and so called perforated flexible tensulae membranes of different dimensions intersecting and linking them. Kinetic energy of a mechanical shock may be dissipated within the solid-liquid composite bone structure into heat via the generation of quasi-chaotic hydromechanic micro-turbulence. It may generate electro-kinetic energy in terms of electric currents and potentials. And the resulting specific structural and surface electrochemical changes may induce the compressible intra-osseal liquid to build up pressure dependent free chemical energy. Innovative bone joint prostheses will have to consider and to be adapted to the nano-material aspects of shock absorption in the operated bones.

  6. Bioreactor activated graft material for early implant fixation in bone

    DEFF Research Database (Denmark)

    Snoek Henriksen, Susan; Ding, Ming; Overgaard, Søren

    2011-01-01

    Introduction The combined incubation of a composite scaffold with bone marrow stromal cells in a perfusion bioreactor could make up a novel hybrid graft material with optimal properties for early fixation of implant to bone. The aim of this study was to create a bioreactor activated graft (BAG......) material, which could induce early implant fixation similar to that of allograft. Two porous scaffold materials incubated with cells in a perfusion bioreactor were tested in this study. Methods and Materials Two groups of 8 skeletally mature female sheep were anaesthetized before aspiration of bone marrow...... Technological Institute, Denmark). The granules were coated with poly-lactic acid (PLA) 12%, in order to increase the mechanical strength of the material (Phusis, France). Scaffold granules (Ø~900-1400 µm, 80% porosity) in group 2 consisted of pure HA/β-TCP (FinCeramica, Italy). For both groups, cells were...

  7. Remodelling of bone and bones. Effects of altered mechanical stress on anlages.

    Science.gov (United States)

    Storey, E; Feik, S A

    1982-04-01

    Tails from 4-day-old Sprague-Dawley rats were bent in situ or skinned bent tail segments were transplanted s.c. into 50 g hosts. Tissue changes were studied for up to 24 weeks by radiographic and histological techniques. The early changes in situ resulted largely from limited translation of bones within their encasing tissues with resorption on the leading (pressure) side inducing thinning, and on the trailing (tension) side thickening of bone. The changes in transplanted anlages occurred in 3 stages: initially, bending of the anlages, with tension between the stretched periosteum and the outer bone surface inducing formation, and compression of cartilage and bone on the inner aspect leading to resorption; then resumption of longitudinal growth and expansion of the bent loop leading to translation of bones within the encasing soft tissues with resorption and thinning of bone on the leading pressure side and formation, with thickening of the inner shaft, on the trailing tension side; and finally with cessation of growth and translation, a reversal to the previous phase. The results support the hypothesis that 2 processes are involved: first, internal stress, and second, translation of bones with, in all instances, pressure inducing resorption and tension inducing formation of bone.

  8. Material Properties of the Mandibular Trabecular Bone

    Directory of Open Access Journals (Sweden)

    Éva Lakatos

    2014-01-01

    Full Text Available The present paper introduces a numerical simulation aided, experimental method for the measurement of Young’s modulus of the trabecular substance in the human mandible. Compression tests were performed on fresh cadaveric samples containing trabecular bone covered with cortical layer, thus avoiding the destruction caused by the sterilization, preservation, and storage and the underestimation of the stiffness resulting from the individual failure of the trabeculae cut on the surfaces. The elastic modulus of the spongiosa was determined by the numerical simulation of each compression test using a specimen specific finite element model of each sample. The received mandibular trabecular bone Young’s modulus values ranged from 6.9 to 199.5 MPa.

  9. Understanding and Targeting Epigenetic Alterations in Acquired Bone Marrow Failure

    Science.gov (United States)

    2013-05-01

    chromatin modifying enzymes (Dalgliesh et al., 2010), DNAmethyltransferases ( Ley et al., 2010), and other genes implicated in epigenetic regulation... Boyle , M., Woolcock, B.W., Kuchenbauer, F., et al. (2010). Somatic mutations altering EZH2 (Tyr641) in follicular and diffuse large B-cell lymphomas of

  10. Alteration of osteoblast arrangement via direct attack by cancer cells: New insights into bone metastasis

    Science.gov (United States)

    Kimura, Yumi; Matsugaki, Aira; Sekita, Aiko; Nakano, Takayoshi

    2017-01-01

    Intact bone tissue exhibits a characteristic anisotropic microstructure derived from collagen fiber alignment and the related c-axis orientation of apatite crystals, which govern the mechanical properties of bone tissue. In contrast, tumor-invaded bone exhibits a disorganized, less-aligned microstructure that results in severely disrupted mechanical function. Despite its importance both in basic principle and in therapeutic applications, the classical understanding of bone metastasis is limited to alterations in bone mass regulated by metastatic cancer cells. In this study, we demonstrate a novel mechanism underlying the disruption of bone tissue anisotropy in metastasized bone. We observed that direct attack by cancer cells on osteoblasts induces the less-organized osteoblast arrangement. Importantly, the crystallographic anisotropy of bone tissue is quantitatively determined by the level of osteoblast arrangement. Osteoblast arrangement was significantly disrupted by physical contact with cancer cells such as osteolytic melanoma B16F10, breast cancer MDA-MB-231, and osteoblastic prostate cancer MDA-PCa-2b cells. The present findings demonstrate that the abnormal arrangement of osteoblasts induced by physical contact with cancer cells facilitates the disorganized microstructure of metastasized bone. PMID:28303941

  11. Altered Bone Metabolism and Bone Density in Patients with Chronic Pancreatitis and Pancreatic Exocrine Insufficiency

    Directory of Open Access Journals (Sweden)

    Stephan Haas

    2015-01-01

    Full Text Available Context Due to maldigestion, pancreatic exocrine insufficiency (PEI in chronic pancreatitis may lead to deficiencies in fat-soluble vitamins, including vitamin D. This may, in turn, can cause disturbances in bone metabolism and reduce bone mineral density. Objective To conduct a prospective study of maldigestion, bone metabolism, and bone mineral density in a group of patients with chronic pancreatitis. Methods A total of 50 male patients with proven chronic pancreatitis (36/50 alcohol; 42/50 smokers were studied. Pancreatic exocrine function was assessed using the fecal elastase-1 test. Blood and urine samples were analyzed for parameters related to pancreatitis, nutrition, endocrine status, and bone metabolism. Bone mineral density was measured with dual-energy X-ray absorption (DXA and conventional vertebral X-rays. A standardized questionnaire for osteoporosis was given. Results Twenty-eight of the patients had PEI (fecal elastase-1 200 µg/g, 25 had bone pain, and 21 had a history of bne fractures. Serum 25-OH-cholecalciferol and urine calcium were decreased and deoxypyridinoline concentrations were increased in urine. Serum calcium, bone-specific alkaline phosphatase, and parathyroid hormone were within normal limits. There was no statistical correlation between three classes of fecal elastase-1 (200 µg/g and calcium, 25-OH-cholecalciferol, or deoxypyridinoline. Of the 15 patients who underwent DXA, 5 had normal bone mineral density (T score >-1, 9 had osteopenia (T score from -1 to -2.5, and 1 had osteoporosis (T score -2.5. There was a trend toward a correlation between low fecal elastase-1 and low T scores (P=0.065. Low fecal elastase-1 correlated with low bone mineral density in conventional X-rays (p<0.05. Patients receiving pancreatic enzyme replacement therapy (PERT had significantly higher DXA values (p<0.05. Conclusions Patients with chronic pancreatitis have osteoporosis, along with abnormal bone metabolism and reduced bone

  12. Development of a piezoelectric bone substitute material

    CERN Document Server

    Al-Bader, Y A

    2000-01-01

    The thesis deals with the preparation and testing of ceramic compositions to be used as bone substitute. The proposed composition consisted of calcium enriched calcium phosphate, kaolin and barium titanate in different ratios. The homogeneous powder mixture was dry pressed at different pressures and fired at temperatures up to 1350 degC for different soaking times. The physical properties of the fired compacts that were tested are bulk density and porosity. These were determined as function of pressing pressure, firing temperature and soaking time for different compositions. The mechanical properties investigated were the ultimate compressive strength and Young's modulus, which were determined for different compositions and forming pressures. The electrical properties investigated were D.C. characteristics (resistivity) and A.C. characteristics (A.C. resistivity, dielectric constant, dielectric loss and loss tangent). The piezoelectric behaviour of the fired compacts was investigated and the piezoelectric coe...

  13. Integrated Multimodal Imaging of Dynamic Bone-Tumor Alterations Associated with Metastatic Prostate Cancer

    NARCIS (Netherlands)

    Brisset, Jean-Christophe; Hoff, Benjamin A.; Chenevert, Thomas L.; Jacobson, Jon A.; Boes, Jennifer L.; Galban, Stefanie; Rehemtulla, Alnawaz; Johnson, Timothy D.; Pienta, Kenneth J.; Galban, Craig J.; Meyer, Charles R.; Schakel, Timothy; Nicolay, Klaas; Alva, Ajjai S.; Hussain, Maha; Ross, Brian D.; Schakel, Tim

    2015-01-01

    Bone metastasis occurs for men with advanced prostate cancer which promotes osseous growth and destruction driven by alterations in osteoblast and osteoclast homeostasis. Patients can experience pain, spontaneous fractures and morbidity eroding overall quality of life. The complex and dynamic cellul

  14. Macroporous bioceramics: a remarkable material for bone regeneration.

    Science.gov (United States)

    Lew, Kien-Seng; Othman, Radzali; Ishikawa, Kunio; Yeoh, Fei-Yee

    2012-09-01

    This review summarises the major developments of macroporous bioceramics used mainly for repairing bone defects. Porous bioceramics have been receiving attention ever since their larger surface area was reported to be beneficial for the formation of more rigid bonds with host tissues. The study of porous bioceramics is important to overcome the less favourable bonds formed between dense bioceramics and host tissues, especially in healing bone defects. Macroporous bioceramics, which have been studied extensively, include hydroxyapatite, tricalcium phosphate, alumina, and zirconia. The pore size and interconnections both have significant effects on the growth rate of bone tissues. The optimum pore size of hydroxyapatite scaffolds for bone growth was found to be 300 µm. The existence of interconnections between pores is critical during the initial stage of tissue ingrowth on porous hydroxyapatite scaffolds. Furthermore, pore formation on β-tricalcium phosphate scaffolds also allowed the impregnation of growth factors and cells to improve bone tissues growth significantly. The formation of vascularised tissues was observed on macroporous alumina but did not take place in the case of dense alumina due to its bioinert nature. A macroporous alumina coating on scaffolds was able to improve the overall mechanical properties, and it enabled the impregnation of bioactive materials that could increase the bone growth rate. Despite the bioinertness of zirconia, porous zirconia was useful in designing scaffolds with superior mechanical properties after being coated with bioactive materials. The pores in zirconia were believed to improve the bone growth on the coated system. In summary, although the formation of pores in bioceramics may adversely affect mechanical properties, the advantages provided by the pores are crucial in repairing bone defects.

  15. Pathogenesis of Bone Alterations in Gaucher Disease: The Role of Immune System

    Directory of Open Access Journals (Sweden)

    Juan Marcos Mucci

    2015-01-01

    Full Text Available Gaucher, the most prevalent lysosomal disorder, is an autosomal recessive inherited disorder due to a deficiency of glucocerebrosidase. Glucocerebrosidase deficiency leads to the accumulation of glucosylceramide primarily in cells of mononuclear-macrophage lineage. Clinical alterations are visceral, hematological, and skeletal. Bone disorder in Gaucher disease produces defects on bone metabolism and structure and patients suffer from bone pain and crisis. Skeletal problems include osteopenia, osteoporosis, osteolytic lesions, and osteonecrosis. On the other hand a chronic stimulation of the immune system is a well-accepted hallmark in this disease. In this review we summarize the latest findings in the mechanisms leading to the bone pathology in Gaucher disease in relationship with the proinflammatory state.

  16. Integrated multimodal imaging of dynamic bone-tumor alterations associated with metastatic prostate cancer.

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Brisset

    Full Text Available Bone metastasis occurs for men with advanced prostate cancer which promotes osseous growth and destruction driven by alterations in osteoblast and osteoclast homeostasis. Patients can experience pain, spontaneous fractures and morbidity eroding overall quality of life. The complex and dynamic cellular interactions within the bone microenvironment limit current treatment options thus prostate to bone metastases remains incurable. This study uses voxel-based analysis of diffusion-weighted MRI and CT scans to simultaneously evaluate temporal changes in normal bone homeostasis along with prostate bone metatastsis to deliver an improved understanding of the spatiotemporal local microenvironment. Dynamic tumor-stromal interactions were assessed during treatment in mouse models along with a pilot prospective clinical trial with metastatic hormone sensitive and castration resistant prostate cancer patients with bone metastases. Longitudinal changes in tumor and bone imaging metrics during delivery of therapy were quantified. Studies revealed that voxel-based parametric response maps (PRM of DW-MRI and CT scans could be used to quantify and spatially visualize dynamic changes during prostate tumor growth and in response to treatment thereby distinguishing patients with stable disease from those with progressive disease (p<0.05. These studies suggest that PRM imaging biomarkers are useful for detection of the impact of prostate tumor-stromal responses to therapies thus demonstrating the potential of multi-modal PRM image-based biomarkers as a novel means for assessing dynamic alterations associated with metastatic prostate cancer. These results establish an integrated and clinically translatable approach which can be readily implemented for improving the clinical management of patients with metastatic bone disease.

  17. Animal models of maternal nutrition and altered offspring bone structure – Bone development across the lifecourse

    Directory of Open Access Journals (Sweden)

    SA Lanham

    2011-11-01

    Full Text Available It is widely accepted that the likelihood of offspring developing heart disease, stroke, or diabetes in later life, is influenced by the their in utero environment and maternal nutrition. There is increasing epidemiological evidence that osteoporosis in the offspring may also be influenced by the mother’s nutrition during pregnancy. This review provides evidence from a range of animal models that supports the epidemiological data; suggesting that lifelong bone development and growth in offspring is determined during gestation.

  18. Mechanical Unloading of Mouse Bone in Microgravity Significantly Alters Cell Cycle Gene Set Expression

    Science.gov (United States)

    Blaber, Elizabeth; Dvorochkin, Natalya; Almeida, Eduardo; Kaplan, Warren; Burns, Brnedan

    2012-07-01

    Spaceflight factors, including microgravity and space radiation, have many detrimental short-term effects on human physiology, including muscle and bone degradation, and immune system dysfunction. The long-term progression of these physiological effects is still poorly understood, and a serious concern for long duration spaceflight missions. We hypothesized that some of the degenerative effects of spaceflight may be caused in part by an inability of stem cells to proliferate and differentiate normally resulting in an impairment of tissue regenerative processes. Furthermore, we hypothesized that long-term bone tissue degeneration in space may be mediated by activation of the p53 signaling network resulting in cell cycle arrest and/or apoptosis in osteoprogenitors. In our analyses we found that spaceflight caused significant bone loss in the weight-bearing bones of mice with a 6.3% reduction in bone volume and 11.9% decrease in bone thickness associated with increased osteoclastic activity. Along with this rapid bone loss we also observed alterations in the cell cycle characterized by an increase in the Cdkn1a/p21 cell cycle arrest molecule independent of Trp53. Overexpression of Cdkn1a/p21 was localized to osteoblasts lining the periosteal surface of the femur and chondrocytes in the head of the femur, suggesting an inhibition of proliferation in two key regenerative cell types of the femur in response to spaceflight. Additionally we found overexpression of several matrix degradation molecules including MMP-1a, 3 and 10, of which MMP-10 was localized to osteocytes within the shaft of the femur. This, in conjunction with 40 nm resolution synchrotron nano-Computed Tomography (nano-CT) observations of an increase in osteocyte lacunae cross-sectional area, perimeter and a decrease in circularity indicates a potential role for osteocytic osteolysis in the observed bone degeneration in spaceflight. To further investigate the genetic response of bone to mechanical

  19. Effects of gamma irradiation on the initial mechanical and material properties of goat bone-patellar tendon-bone allografts

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, M.J.; Butler, D.L.; Grood, E.S.; Bylski-Austrow, D.I.; Levy, M.S.; Noyes, F.R. (Univ. of Cincinnati, OH (USA))

    1991-03-01

    The effects of {sup 60}Co gamma irradiation on the initial mechanical properties of the composite bone-patellar tendon-bone unit (CU) and the tendon midsubstance (TM) were studied. Frozen specimens were exposed to either 2 or 3 Mrad of gamma irradiation. Paired frozen specimens served as intraanimal controls. Treatment effects on the CU were assessed using four mechanical parameters. Effects on the TM were assessed using four material parameters measured using an optical surface-strain analysis system. The maximum force and strain energy to maximum force of the composite unit were significantly reduced 27% and 40%, respectively, after 3 Mrad of irradiation (p less than .05). Mechanical properties of the CU were not significantly altered, however, following 2 Mrad of irradiation. Based on individual paired contrasts between treatment and control, significant differences were also found in the material properties of the tendon midsubstance. The maximum stress, maximum strain, and strain energy density to maximum stress were significantly reduced following 3 Mrad, but not 2 Mrad, of irradiation. The results provide important time zero material property data, which will be useful for later anterior cruciate ligament reconstruction studies using irradiated allograft patellar tendons in the goat model and other animal models as well.

  20. Comparative experiment of four different materials as carriers of Bone morphogenetic protein to repair long bone defect

    Institute of Scientific and Technical Information of China (English)

    WEI Kuan-hai; PEI Guo-xian; YANG Run-gong

    2001-01-01

    @@ OBJECTIVE To investigate the effects of four different materials as carriers of bone morphogenetic protein (BMP) to repair long bone defect. METHODS 12 mm radius bone defects were made. They were divided into 4 groups in random and repaired respectively with the vascular muscle flap combined with FS/BMP (group A), vascular muscle flap/BMP (group B), bloodless muscle flap/BMP (group C) and autolyzed antigen-extracted allogeneic bone (AAA)/BMP (group D).Their abilities of bone forming to repair bone defects were observed.

  1. Biomechanical Stability of Juvidur and Bone Models on Osteosyntesic Materials

    Science.gov (United States)

    Grubor, Predrag; Mitković, Milorad; Grubor, Milan; Mitković, Milan; Meccariello, Luigi; Falzarano, Gabriele

    2016-01-01

    Introduction: Artificial models can be useful at approximate and qualitative research, which should give the preliminary results. Artificial models are usually made of photo-elastic plastic e.g.. juvidur, araldite in the three-dimensional contour shape of the bone. Anatomical preparations consist of the same heterogeneous, structural materials with extremely anisotropic and unequal highly elastic characteristics, which are embedded in a complex organic structure. The aim of the study: Examine the budget voltage and deformation of: dynamic compression plate (DCP), locking compression plate (LCP), Mitkovic internal fixator (MIF), Locked intramedullary nailing (LIN) on the compressive and bending forces on juvidur and veal bone models and compared the results of these two methods (juvidur, veal bone). Material and Methods: For the experimental study were used geometrically identical, anatomically shaped models of Juvidur and veal bones diameter of 30 mm and a length of 100 mm. Static tests were performed with SHIMADZU AGS-X testing machine, where the force of pressure (compression) increased from 0 N to 500 N, and then conducted relief. Bending forces grew from 0 N to 250 N, after which came into sharp relief. Results: On models of juvidur and veal bones studies have confirmed that uniform stability at the site of the fracture MIF with a coefficient ranking KMIF=0,1971, KLIN=0,2704, KDCP=0,2727 i KLCP=0,5821. Conclusion: On models of juvidur and veal bones working with Shimadzu AGS-X testing machine is best demonstrated MIF with a coefficient of 0.1971. PMID:27708489

  2. Modern materials in fabrication of scaffolds for bone defect replacement

    Science.gov (United States)

    Bazlov, V. A.; Mamuladze, T. Z.; Pavlov, V. V.; Kirilova, I. A.; Sadovoy, M. A.

    2016-08-01

    The article defines the requirements for modern scaffold-forming materials and describes the main advantages and disadvantages of various synthetic materials. Osseointegration of synthetic scaffolds approved for use in medical practice is evaluated. Nylon 618 (certification ISO9001 1093-1-2009) is described as the most promising synthetic material used in medical practice. The authors briefly highlight the issues of individual bone grafting with the use of 3D printing technology. An example of contouring pelvis defect after removal of a giant tumor with the use of 3D models is provided.

  3. Material Mismatch Effect on the Fracture of a Bone-Composite Cement Interface.

    Science.gov (United States)

    Khandaker, M; Tarantini, S

    2012-12-01

    The interfacial mechanics at the bone-implant interface is a critical issue for implant fixation and the filling of bone defects created by tumors and/or their excision. Our previous study found that micron and nano sizes MgO particles improved the fracture toughness of bone-cement interfaces under tension loading. The strength of bonding of different types of bone with different types of implants may not be the same. The aims of this research were to determine the influences of material mismatch due to bone orientation and a magnesium oxide (MgO) filler material for PMMA bone cement on the mechanical strength between bone and bone cement specimens. This research studied the longitudinal and transverse directions bovine cortical bone as different bone materials and poly Methyl MethAcrylate (PMMA) bone cement with and without MgO additives as different implant materials. The scope of work for this study was: (1) to determine the bending strength and modulus of different bone and bone cement specimens, (2) to determine whether inclusion of MgO particles on PMMA has any influence on these mechanical properties of PMMA, and (3) to determine whether bone orientation and inclusion of MgO particles with PMMA has any influence on the interface strength between bone and PMMA. This study showed that bone orientation has statistically significant effect on the bonding strength between bone and bone cement specimens (P value0.05).

  4. Leishmania donovani infection induces anemia in hamsters by differentially altering erythropoiesis in bone marrow and spleen.

    Directory of Open Access Journals (Sweden)

    William P Lafuse

    Full Text Available Leishmania donovani is a parasite that causes visceral leishmaniasis by infecting and replicating in macrophages of the bone marrow, spleen, and liver. Severe anemia and leucopenia is associated with the disease. Although immune defense mechanisms against the parasite have been studied, we have a limited understanding of how L. donovani alters hematopoiesis. In this study, we used Syrian golden hamsters to investigate effects of L. donovani infection on erythropoiesis. Infection resulted in severe anemia and leucopenia by 8 weeks post-infection. Anemia was associated with increased levels of serum erythropoietin, which indicates the hamsters respond to the anemia by producing erythropoietin. We found that infection also increased numbers of BFU-E and CFU-E progenitor populations in the spleen and bone marrow and differentially altered erythroid gene expression in these organs. In the bone marrow, the mRNA expression of erythroid differentiation genes (α-globin, β-globin, ALAS2 were inhibited by 50%, but mRNA levels of erythroid receptor (c-kit, EpoR and transcription factors (GATA1, GATA2, FOG1 were not affected by the infection. This suggests that infection has a negative effect on differentiation of erythroblasts. In the spleen, erythroid gene expression was enhanced by infection, indicating that the anemia activates a stress erythropoiesis response in the spleen. Analysis of cytokine mRNA levels in spleen and bone marrow found that IFN-γ mRNA is highly increased by L. donovani infection. Expression of the IFN-γ inducible cytokine, TNF-related apoptosis-inducing ligand (TRAIL, was also up-regulated. Since TRAIL induces erythroblasts apoptosis, apoptosis of bone marrow erythroblasts from infected hamsters was examined by flow cytometry. Percentage of erythroblasts that were apoptotic was significantly increased by L. donovani infection. Together, our results suggest that L. donovani infection inhibits erythropoiesis in the bone marrow by

  5. Bone remodeling induced by dental implants of functionally graded materials.

    Science.gov (United States)

    Lin, Daniel; Li, Qing; Li, Wei; Swain, Michael

    2010-02-01

    Functionally graded material (FGM) had been developed as a potential implant material to replace titanium for its improved capability of initial osseointegration. The idea behind FGM dental implant is that its properties can be tailored in accordance with the biomechanical needs at different regions adapting to its hosting bony tissues, therefore creating an improved overall integration and stability in the entire restoration. However, there have been very few reports available so far on predicting bone remodeling induced by FGM dental implants. This article aims to evaluate bone remodeling when replacing the titanium with a hydroxyapatite/collagen (HAP/Col) FGM model. A finite element model was constructed in the buccal-lingual section of a dental implant-bone structure generated from in vivo CT scan images. The remodeling simulation was performed over a 4 year healing period. Comparisons were made between the titanium implant and various FGM implants of this model. The FGM implants showed an improved bone remodeling outcome. The study is expected to provide a basis for future development of FGM implants.

  6. Tooth and bone deformation: structure and material properties by ESPI

    Science.gov (United States)

    Zaslansky, Paul; Shahar, Ron; Barak, Meir M.; Friesem, Asher A.; Weiner, Steve

    2006-08-01

    In order to understand complex-hierarchical biomaterials such as bones and teeth, it is necessary to relate their structure and mechanical-properties. We have adapted electronic speckle pattern-correlation interferometry (ESPI) to make measurements of deformation of small water-immersed specimens of teeth and bones. By combining full-field ESPI with precision mechanical loading we mapped sub-micron displacements and determined material-properties of the samples. By gradually and elastically compressing the samples, we compensate for poor S/N-ratios and displacement differences of about 100nm were reliably determined along samples just 2~3mm long. We produced stress-strain curves well within the elastic performance range of these materials under biologically relevant conditions. For human tooth-dentin, Young's modulus in inter-dental areas of the root is 40% higher than on the outer sides. For cubic equine bone samples the compression modulus of axial orientations is about double the modulus of radial and tangential orientations (20 GPa versus 10 GPa respectively). Furthermore, we measured and reproduced a surprisingly low Poisson's ratio, which averaged about 0.1. Thus the non-contact and non-destructive measurements by ESPI produce high sensitivity analyses of mechanical properties of mineralized tissues. This paves the way for mapping deformation-differences of various regions of bones, teeth and other biomaterials.

  7. Vitamin D and calcium supplementation for three years in postmenopausal osteoporosis significantly alters bone mineral and organic matrix quality.

    Science.gov (United States)

    Paschalis, E P; Gamsjaeger, S; Hassler, N; Fahrleitner-Pammer, A; Dobnig, H; Stepan, J J; Pavo, I; Eriksen, E F; Klaushofer, K

    2017-02-01

    Prospective, controlled clinical trials in postmenopausal osteoporosis typically compare effects of an active drug with placebo in addition to vitamin D and calcium supplementation in both treatment arms. While clinical benefits are documented, the effect of this supplementation in the placebo arm and in clinical practice on bone material composition properties is unknown. The purpose of the present study was to evaluate these bone quality indices (specifically mineral/matrix, nanoporosity, glycosaminoglycan content, mineral maturity/crystallinity, and pyridinoline content) in patients that either received long-term vitamin D (400-1200IU) and calcium (1.0-1.5g) supplementation, or did not. We have analyzed by Raman microspectroscopy the bone forming trabecular surfaces of iliac crest in pre-treatment samples of a teriparatide study and the endpoint biopsies of the control arm obtained from the HORIZON trial. In general, the mineral/matrix ratio and the glycosaminoglycan (GAG) content was higher while nanoporosity, (a surrogate for tissue water content), the mineral maturity/crystallinity (MMC) and the pyridinoline (Pyd) content was lower in patients without long-term supplementation. Moreover, all indices were significantly dependent on tissue age. In conclusion, vitamin D and calcium supplementation is associated with altered mineral and organic matrix properties.

  8. Journey of bone graft materials in periodontal therapy: A chronological review

    Directory of Open Access Journals (Sweden)

    Jitendra Kumar

    2016-01-01

    Full Text Available Bone, the basic building block of the healthy periodontium, is affected in most of the periodontal diseases and can be managed either by mechanically recontouring it or by grafting techniques, which encourages regeneration where it has been lost. Bone replacement grafts are widely used to promote bone formation and periodontal regeneration. Bone grafting, placing bone or bone substitutes into defects created by the disease process, acts like a scaffold upon which the body generates its own, new bone. A wide range of bone grafting materials, including bone grafts and bone graft substitutes, have been applied and evaluated clinically, including autografts, allografts, xenografts, and alloplasts. This review provides an overview of the clinical application, biologic function, and advantages and disadvantages of various types of bone graft materials used in periodontal therapy till date with emphasis on recent advances in this field.

  9. Alterations in bone and erythropoiesis in hemolytic anemia: comparative study in bled, phenylhydrazine-treated and Plasmodium-infected mice.

    Directory of Open Access Journals (Sweden)

    Robert Moreau

    Full Text Available Sustained erythropoiesis and concurrent bone marrow hyperplasia are proposed to be responsible for low bone mass density (BMD in chronic hemolytic pathologies. As impaired erythropoiesis is also frequent in these conditions, we hypothesized that free heme may alter marrow and bone physiology in these disorders. Bone status and bone marrow erythropoiesis were studied in mice with hemolytic anemia (HA induced by phenylhydrazine (PHZ or Plasmodium infection and in bled mice. All treatments resulted in lower hemoglobin concentrations, enhanced erythropoiesis in the spleen and reticulocytosis. The anemia was severe in mice with acute hemolysis, which also had elevated levels of free heme and ROS. No major changes in cellularity and erythroid cell numbers occurred in the bone marrow of bled mice, which generated higher numbers of erythroid blast forming units (BFU-E in response to erythropoietin. In contrast, low numbers of bone marrow erythroid precursors and BFU-E and low concentrations of bone remodelling markers were measured in mice with HA, which also had blunted osteoclastogenesis, in opposition to its enhancement in bled mice. The alterations in bone metabolism were accompanied by reduced trabecular bone volume, enhanced trabecular spacing and lower trabecular numbers in mice with HA. Taken together our data suggests that hemolysis exerts distinct effects to bleeding in the marrow and bone and may contribute to osteoporosis through a mechanism independent of the erythropoietic stress.

  10. Alterations in Bone and Erythropoiesis in Hemolytic Anemia: Comparative Study in Bled, Phenylhydrazine-Treated and Plasmodium-Infected Mice

    Science.gov (United States)

    Moreau, Robert; Tshikudi Malu, Diane; Dumais, Mathieu; Dalko, Esther; Gaudreault, Véronique; Roméro, Hugo; Martineau, Corine; Kevorkova, Olha; Dardon, Jaime Sanchez; Dodd, Erin Lynn; Bohle, David Scott; Scorza, Tatiana

    2012-01-01

    Sustained erythropoiesis and concurrent bone marrow hyperplasia are proposed to be responsible for low bone mass density (BMD) in chronic hemolytic pathologies. As impaired erythropoiesis is also frequent in these conditions, we hypothesized that free heme may alter marrow and bone physiology in these disorders. Bone status and bone marrow erythropoiesis were studied in mice with hemolytic anemia (HA) induced by phenylhydrazine (PHZ) or Plasmodium infection and in bled mice. All treatments resulted in lower hemoglobin concentrations, enhanced erythropoiesis in the spleen and reticulocytosis. The anemia was severe in mice with acute hemolysis, which also had elevated levels of free heme and ROS. No major changes in cellularity and erythroid cell numbers occurred in the bone marrow of bled mice, which generated higher numbers of erythroid blast forming units (BFU-E) in response to erythropoietin. In contrast, low numbers of bone marrow erythroid precursors and BFU-E and low concentrations of bone remodelling markers were measured in mice with HA, which also had blunted osteoclastogenesis, in opposition to its enhancement in bled mice. The alterations in bone metabolism were accompanied by reduced trabecular bone volume, enhanced trabecular spacing and lower trabecular numbers in mice with HA. Taken together our data suggests that hemolysis exerts distinct effects to bleeding in the marrow and bone and may contribute to osteoporosis through a mechanism independent of the erythropoietic stress. PMID:23029401

  11. Evolutionary design of bone scaffolds with reference to material selection.

    Science.gov (United States)

    Heljak, M K; Swięszkowski, W; Lam, C X F; Hutmacher, D W; Kurzydłowski, K J

    2012-01-01

    The favourable scaffold for bone tissue engineering should have desired characteristic features, such as adequate mechanical strength and three-dimensional open porosity, which guarantee a suitable environment for tissue regeneration. In fact, the design of such complex structures like bone scaffolds is a challenge for investigators. One of the aims is to achieve the best possible mechanical strength-degradation rate ratio. In this paper we attempt to use numerical modelling to evaluate material properties for designing bone tissue engineering scaffold fabricated via the fused deposition modelling technique. For our studies the standard genetic algorithm was used, which is an efficient method of discrete optimization. For the fused deposition modelling scaffold, each individual strut is scrutinized for its role in the architecture and structural support it provides for the scaffold, and its contribution to the overall scaffold was studied. The goal of the study was to create a numerical tool that could help to acquire the desired behaviour of tissue engineered scaffolds and our results showed that this could be achieved efficiently by using different materials for individual struts. To represent a great number of ways in which scaffold mechanical function loss could proceed, the exemplary set of different desirable scaffold stiffness loss function was chosen.

  12. Bone cell expression on titanium surfaces is altered by sterilization treatments.

    Science.gov (United States)

    Stanford, C M; Keller, J C; Solursh, M

    1994-05-01

    Phenotypic responses of rat calvarial osteoblast-like cells (RCOB) were evaluated on commercially pure titanium (cpTi) surfaces when cultured at high density (5100 cells/mm2). These surfaces were prepared to three different clinically relevant surface preparations (1-micron, 600-grit, and 50-microns-grit sand-blast), followed by sterilization with either ultraviolet light, ethylene oxide, argon plasma-cleaning, or routine clinical autoclaving. Osteocalcin and alkaline phosphatase, but not collagen expression, were significantly affected by surface roughness when these surfaces were altered by argon plasma-cleaning. In general, plasma-cleaned cpTi surfaces demonstrated an inverse relationship between surface roughness and phenotypic markers for a bone-like response. On a per-cell basis, levels of the bone-specific protein, osteocalcin, and the enzymatic activity of alkaline phosphatase were highest on the smooth 1-micron polished surface and lowest on the roughest surfaces for the plasma-cleaned cpTi. Detectable bone cell expression can be altered by clinically relevant surfaces prepared by standard dental implant preparation techniques.

  13. Use of osteoplastic material to guide bone tissue regeneration deffect.

    Science.gov (United States)

    Machavariani, A; Mazmishvili, K; Grdzelidze, T; Menabde, G; Amiranashvili, I

    2011-12-01

    The goal of research was study of restoration processes in jaw-teeth bone defects by application of osteoplastic materials in the experiment. The experiment was performed over 32 white (6-12 month old) rats; the animals were divided into 2 groups; 16 animals were enrolled in the first group; the section was performed in the edge of lower jaw; the lower jaw body was revealed. Under the effect of the dental drilling machine and the # 1 cooling mean by the fissure bohrium (distilled water) the defect of the dimension of 2x2 mm was created; the defect was washed by 0/9% saline to remove the bone sawdust; the wound was sutured tightly, in layers. The second group of the experiment was staffed with 16 animals (main group); the similar bone defect of the size 2 x 2mm was created on the rat's jaw's body. After washing of modeled defect we inserted osteopathic materials PORESORB-TCP crystals with the size of 0,6-1.0 mm the wound was sutured tightly, in layers. After the 3-rd, 15-th, 30-th and 90-th days from the date of operation there was performed X-ray and morphological examination over the animals in the control as well as the main group. The analysis of the examination performed over the experimental materials showed that in the control group in samples taken at 90th day the defects were not completely restored. In the test group in samples taken at 90th day reparative regeneration is confirmed. This is stimulated by the factor that within the main group's animals the defect regeneration process is supported with the osteoplastic material PORESORB-TCP.

  14. Current trends and future perspectives of bone substitute materials - from space holders to innovative biomaterials.

    Science.gov (United States)

    Kolk, Andreas; Handschel, Jörg; Drescher, Wolf; Rothamel, Daniel; Kloss, Frank; Blessmann, Marco; Heiland, Max; Wolff, Klaus-Dietrich; Smeets, Ralf

    2012-12-01

    An autologous bone graft is still the ideal material for the repair of craniofacial defects, but its availability is limited and harvesting can be associated with complications. Bone replacement materials as an alternative have a long history of success. With increasing technological advances the spectrum of grafting materials has broadened to allografts, xenografts, and synthetic materials, providing material specific advantages. A large number of bone-graft substitutes are available including allograft bone preparations such as demineralized bone matrix and calcium-based materials. More and more replacement materials consist of one or more components: an osteoconductive matrix, which supports the ingrowth of new bone; and osteoinductive proteins, which sustain mitogenesis of undifferentiated cells; and osteogenic cells (osteoblasts or osteoblast precursors), which are capable of forming bone in the proper environment. All substitutes can either replace autologous bone or expand an existing amount of autologous bone graft. Because an understanding of the properties of each material enables individual treatment concepts this review presents an overview of the principles of bone replacement, the types of graft materials available, and considers future perspectives. Bone substitutes are undergoing a change from a simple replacement material to an individually created composite biomaterial with osteoinductive properties to enable enhanced defect bridging.

  15. Bone mineral and body composition alterations in paediatric cystic fibrosis patients

    Energy Technology Data Exchange (ETDEWEB)

    Reix, Philippe; Bellon, Gabriel [Hopital Femme Mere Enfant, Service de Pediatrie, Pneumologie, Allergologie, Mucoviscidose, Bron (France); Braillon, Pierre [Hospices Civils de Lyon, Service d' Imagerie Foetale et Pediatrique, Bron (France)

    2010-03-15

    With the increased life span of cystic fibrosis (CF) patients, CF-related bone diseases could have an increased prevalence and morbidity in this group. In children, previous retrospective and prospective studies have yielded conflicting results on bone mineralization. To monitor body composition and bone mineral status of children with CF. We reviewed the dual-energy X-ray absorptiometry (DXA) data of 161 children with CF (age 10 {+-} 4.8 years). Total body bone mineral content (BMCt), total lean tissue mass (LTMt) and total fat mass (FMt) were measured and compared to expected data calculated from ideal weight for height (Wi; e.g. BMCti, LTMti, FMti). The bt (BMCt/BMCti), lt (LTMt/LTMti) and ft (FMt/FMti) ratios were used as quantitative variables. Low bt ratio was found at all ages (mean bt ratio 0.94{+-}0.10; P<0.001), even in children <6 years of age. However, the children's BMCt was satisfactorily adapted to their weight. lt and ft ratios were not constant across age groups. Children <10 years had 8% reduction of their lt ratio, maintaining normal levels thereafter. The opposite trend was found for ft ratio. Poor clinical, nutritional status and vitamin A levels were correlated with bt and lt ratios. Our results indicate that children with CF could have early alterations in their bone status and that lt and ft ratios did not have constant values across ages. Interpreting DXA data using this approach is suitable in children with CF. (orig.)

  16. Alendronate Can Improve Bone Alterations in Experimental Diabetes by Preventing Antiosteogenic, Antichondrogenic, and Proadipocytic Effects of AGEs on Bone Marrow Progenitor Cells

    Science.gov (United States)

    2016-01-01

    Bisphosphonates such as alendronate are antiosteoporotic drugs that inhibit the activity of bone-resorbing osteoclasts and secondarily promote osteoblastic function. Diabetes increases bone-matrix-associated advanced glycation end products (AGEs) that impair bone marrow progenitor cell (BMPC) osteogenic potential and decrease bone quality. Here we investigated the in vitro effect of alendronate and/or AGEs on the osteoblastogenic, adipogenic, and chondrogenic potential of BMPC isolated from nondiabetic untreated rats. We also evaluated the in vivo effect of alendronate (administered orally to rats with insulin-deficient Diabetes) on long-bone microarchitecture and BMPC multilineage potential. In vitro, the osteogenesis (Runx2, alkaline phosphatase, type 1 collagen, and mineralization) and chondrogenesis (glycosaminoglycan production) of BMPC were both decreased by AGEs, while coincubation with alendronate prevented these effects. The adipogenesis of BMPC (PPARγ, intracellular triglycerides, and lipase) was increased by AGEs, and this was prevented by coincubation with alendronate. In vivo, experimental Diabetes (a) decreased femoral trabecular bone area, osteocyte density, and osteoclastic TRAP activity; (b) increased bone marrow adiposity; and (c) deregulated BMPC phenotypic potential (increasing adipogenesis and decreasing osteogenesis and chondrogenesis). Orally administered alendronate prevented all these Diabetes-induced effects on bone. Thus, alendronate could improve bone alterations in diabetic rats by preventing the antiosteogenic, antichondrogenic, and proadipocytic effects of AGEs on BMPC. PMID:27840829

  17. Alendronate Can Improve Bone Alterations in Experimental Diabetes by Preventing Antiosteogenic, Antichondrogenic, and Proadipocytic Effects of AGEs on Bone Marrow Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Sara Rocío Chuguransky

    2016-01-01

    Full Text Available Bisphosphonates such as alendronate are antiosteoporotic drugs that inhibit the activity of bone-resorbing osteoclasts and secondarily promote osteoblastic function. Diabetes increases bone-matrix-associated advanced glycation end products (AGEs that impair bone marrow progenitor cell (BMPC osteogenic potential and decrease bone quality. Here we investigated the in vitro effect of alendronate and/or AGEs on the osteoblastogenic, adipogenic, and chondrogenic potential of BMPC isolated from nondiabetic untreated rats. We also evaluated the in vivo effect of alendronate (administered orally to rats with insulin-deficient Diabetes on long-bone microarchitecture and BMPC multilineage potential. In vitro, the osteogenesis (Runx2, alkaline phosphatase, type 1 collagen, and mineralization and chondrogenesis (glycosaminoglycan production of BMPC were both decreased by AGEs, while coincubation with alendronate prevented these effects. The adipogenesis of BMPC (PPARγ, intracellular triglycerides, and lipase was increased by AGEs, and this was prevented by coincubation with alendronate. In vivo, experimental Diabetes (a decreased femoral trabecular bone area, osteocyte density, and osteoclastic TRAP activity; (b increased bone marrow adiposity; and (c deregulated BMPC phenotypic potential (increasing adipogenesis and decreasing osteogenesis and chondrogenesis. Orally administered alendronate prevented all these Diabetes-induced effects on bone. Thus, alendronate could improve bone alterations in diabetic rats by preventing the antiosteogenic, antichondrogenic, and proadipocytic effects of AGEs on BMPC.

  18. Development of bioactive materials using reticulated ceramics for bone substitute

    Science.gov (United States)

    Jiang, Gengwei

    For hard tissue prosthetics, it is necessary to seek novel synthesis routes by which a real structural bone can be simulated in terms of bioactivity, porosity, and mechanical behavior. The work presented here deals with the development of such a component by a novel synthesis route for bone implantation. To enhance the mechanical properties, an industrial alumina has been selected as the substrate. Alumina is not only bio inert but also mechanically strong which makes it an ideal substrate for bone substitute. The high porosity is achieved via a sponge technique by which both pore size and density can be changed easily. The bioactivity is induced by coating a highly bioactive HA film onto the inner pore surfaces of the reticulated alumina. Based on this concept, the research has focused on the coating of HA onto inner pore surfaces of the reticulated alumina via several effective methods that are developed in our laboratory. No previous studies have so far been reported on coating inner surfaces of small-diameter pores ranging from 0.1--1.0 mm. The key materials processing issues dealt with in this work include precursor chemistry, coating procedures, synthesis of coated component, interface structure study, film adhesion strength testing, and mechanical properties of the component. This novel approach has shown great promise in synthesizing bone substitutes. To determine the applicability of the coated component in hard tissue prosthetics, a bioactivity study has been carried out. By immersing the synthetic HA into simulated body fluid (SBF), the bioresponse has been measured for a variety of samples with different processing conditions. Fundamental aspects of this study are centered on the effects of structural characteristics of HA on the bioactivity. Based on extensive IR and XRD experimental data, it has been found that the bioactivity of HA is sensitively controlled by the structural crystallinity of the HA and its specific surface area. Furthermore, based on

  19. Organoapatites: materials for artificial bone. II. Hardening reactions and properties.

    Science.gov (United States)

    Stupp, S I; Mejicano, G C; Hanson, J A

    1993-03-01

    This article reports on chemical reactions and the properties they generated in artificial bone materials termed "organoapatites." These materials are synthesized using methodology we reported in the previous article of this series. Two different processes were studied here for the transition from organoapatite particles to implants suitable for the restoration of the skeletal system. One process involved the hardening of powder compacts by beams of blue light derived from a lamp or a laser and the other involved pressure-induced interdiffusion of polymers. In both cases, the hardening reaction involved the formation of a polyion complex between two polyelectrolytes. In the photo-induced reaction an anionic electrolyte polymerizes to form the coulombic network and in the pressure-induced one, pressure forms the complex by interdiffusion of two polyions. Model reactions were studied using various polycations. Based on these results the organoapatite selected for the study was that containing dispersed poly(L-lysine) and sodium acrylate as the anionic monomer. The organomineral particles can be pressed at room temperature into objects of great physical integrity and hydrolytic stability relative to anorganic controls. The remarkable fact about these objects is that intimate molecular dispersion of only 2-3% by weight organic material provides integrity to the mineral network in an aqueous medium and also doubles its tensile strength. This integrity is essentially nonexistent in "anorganic" samples prepared by the same methodology used in organoapatite synthesis. The improvement in properties was most effectively produced by molecular bridges formed by photopolymerization. The photopolymerization leads to the "hardening" of pellets prepared by pressing of organoapatite powders. The reaction was found to be more facile in the microstructure of the organomineral, and it is potentially useful in the surgical application of organoapatites as artificial bone.

  20. Bone Formation in a Rat Tibial Defect Model Using Carboxymethyl Cellulose/BioC/Bone Morphogenic Protein-2 Hybrid Materials

    Directory of Open Access Journals (Sweden)

    Sang-Heon Song

    2014-01-01

    Full Text Available The objective of this study was to assess whether carboxymethyl cellulose- (CMC- based hydrogel containing BioC (biphasic calcium phosphate (BCP; tricalcium phosphate (TCP : hydroxyapatite (Hap = 70 : 30 and bone morphogenic protein-2 (BMP-2 led to greater bone formation than CMC-based hydrogel containing BioC without BMP-2. In order to demonstrate bone formation at 4 and 8 weeks, plain radiographs, microcomputed tomography (micro-CT evaluation, and histological studies were performed after implantation of all hybrid materials on an 8 mm defect of the right tibia in rats. The plain radiographs and micro-CT analyses revealed that CMC/BioC/BMP-2 (0.5 mg led to much greater mineralization at 4 and 8 weeks than did CMC/BioC or CMC/Bio/BMP-2 (0.1 mg. Likewise, bone formation and bone remodeling studies revealed that CMC/BioC/BMP-2 (0.5 mg led to a significantly greater amount of bone formation and bone remodeling at 4 and 8 weeks than did CMC/BioC or CMC/BioC/BMP-2 (0.1 mg. Histological studies revealed that mineralized bone tissue was present around the whole circumference of the defect site with CMC/BioC/BMP-2 (0.5 mg but not with CMC/BioC or CMC/BioC/BMP-2 (0.1 mg at 4 and 8 weeks. These results suggest that CMC/BioC/BMP-2 hybrid materials induced greater bone formation than CMC/BioC hybrid materials. Thus, CMC/BioC/BMP-2 hybrid materials may be used as an injectable substrate to regenerate bone defects.

  1. Bioactive ceramic-based materials with designed reactivity for bone tissue regeneration

    OpenAIRE

    Ohtsuki, Chikara; Kamitakahara, Masanobu; Miyazaki, Toshiki

    2009-01-01

    Bioactive ceramics have been used clinically to repair bone defects owing to their biological affinity to living bone; i.e. the capability of direct bonding to living bone, their so-called bioactivity. However, currently available bioactive ceramics do not satisfy every clinical application. Therefore, the development of novel design of bioactive materials is necessary. Bioactive ceramics show osteoconduction by formation of biologically active bone-like apatite through chemical reaction of t...

  2. Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis

    Directory of Open Access Journals (Sweden)

    De-Gang Yu

    2015-01-01

    Full Text Available Background: The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA. However, the characteristics of subchondral bone alterations remain unresolved. The present study aimed to observe the dynamic alterations in the microarchitecture, mineralization, and mechanical properties of subchondral bone during the progression of OA. Methods: A medial meniscal tear (MMT operation was performed in 128 adult Sprague Dawley rats to induce OA. At 2, 4, 8, and 12 weeks following the MMT operation, cartilage degeneration was evaluated using toluidine blue O staining, whereas changes in the microarchitecture indices and tissue mineral density (TMD, mineral-to-collagen ratio, and intrinsic mechanical properties of subchondral bone plates (BPs and trabecular bones (Tbs were measured using micro-computed tomography scanning, confocal Raman microspectroscopy and nanoindentation testing, respectively. Results: Cartilage degeneration occurred and worsened progressively from 2 to 12 weeks after OA induction. Microarchitecture analysis revealed that the subchondral bone shifted from bone resorption early (reduced trabecular BV/TV, trabecular number, connectivity density and trabecular thickness [Tb.Th], and increased trabecular spacing (Tb.Sp at 2 and 4 weeks to bone accretion late (increased BV/TV, Tb.Th and thickness of subchondral bone plate, and reduced Tb.Sp at 8 and 12 weeks. The TMD of both the BP and Tb displayed no significant changes at 2 and 4 weeks but decreased at 8 and 12 weeks. The mineral-to-collagen ratio showed a significant decrease from 4 weeks for the Tb and from 8 weeks for the BP after OA induction. Both the elastic modulus and hardness of the Tb showed a significant decrease from 4 weeks after OA induction. The BP showed a significant decrease in its elastic modulus from 8 weeks and its hardness from 4 weeks. Conclusion: The microarchitecture, mineralization and mechanical

  3. Quantification of alterations in cortical bone geometry using Site Specificity Software in mouse models of aging and the responses to ovariectomy and altered loading

    Directory of Open Access Journals (Sweden)

    Gabriel L Galea

    2015-04-01

    Full Text Available Investigations into the effect of (remodelling stimuli on cortical bone in rodents normally rely on analysis of changes in bone mass and architecture at a narrow cross-sectional site. However, it is well established that the effects of axial loading produce site-specific changes throughout bones’ structure. Non-mechanical influences (e.g. hormones can be additional to or oppose locally-controlled adaptive responses and may have more generalized effects. Tools currently available to study site-specific cortical bone adaptation are limited. Here we applied novel Site-Specificity software to measure bone mass and architecture at each 1% site along the length of the mouse tibia from standard micro-computed tomography (μCT images. Resulting measures are directly comparable to those obtained through μCT analysis (R2 > 0.96. Site-Specificity Analysis was used to compare a number of parameters in tibiae from young adult (19-week-old versus aged (19-month-old mice; ovariectomized and entire mice; limbs subjected to short periods of axial loading or disuse induced by sciatic neurectomy. Age was associated with uniformly reduced cortical thickness and site-specific decreases in cortical area most apparent in the proximal tibia. Mechanical loading site-specifically increased cortical area and thickness in the proximal tibia. Disuse uniformly decreased cortical thickness and decreased cortical area in the proximal tibia. Ovariectomy uniformly reduced cortical area without altering cortical thickness. Differences in polar moment of inertia between experimental groups were only observed in the proximal tibia. Ageing and ovariectomy also altered eccentricity in the distal tibia. In summary, Site-Specificity Analysis provides a valuable tool for measuring changes in cortical bone mass and architecture along the entire length of a bone. Changes in the (remodelling response determined at a single site may not reflect the response at different locations within

  4. Tissue reaction and material characteristics of four bone substitutes

    DEFF Research Database (Denmark)

    Jensen, S S; Aaboe, M; Pinholt, E M;

    1996-01-01

    The aim of the present study was to qualitatively and quantitatively compare the tissue reactions around four different bone substitutes used in orthopedic and craniofacial surgery. Cylinders of two bovine bone substitutes (Endobon and Bio-Oss) and two coral-derived bone substitutes (Pro Osteon 5...

  5. Hierarcially biomimetic bone materials: from nanometer to millimeter

    Institute of Scientific and Technical Information of China (English)

    ZHANG W.; CUI F. Z.; LIAO S. S.

    2001-01-01

    @@ The bone composite was produced by biomimetic synthesis. It shows some features of natural bone in both composition and microstructure. And the collagen moleculars and the nano-crystal hydroxyapatite assemble into ultrastructure similar to natural bone. It possesses porous structure with porosity from 100μm to 500μm after mixed with PLA (poly lactic acid).

  6. Degradability of injectable calcium sulfate/mineralized collagen-based bone repair material and its effect on bone tissue regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zonggang, E-mail: chenzg@sdu.edu.cn [National Glycoengineering Research Center, Shandong University, Jinan 250100 (China); Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Kang, Lingzhi [National Glycoengineering Research Center, Shandong University, Jinan 250100 (China); Meng, Qing-Yuan [Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Liu, Huanye [Department of Prosthodontics, School of Stomatology, China Medical University, Shenyang 110001 (China); Wang, Zhaoliang [Jinan Military General Hospital of PLA, Jinan 250031 (China); Guo, Zhongwu, E-mail: zwguo@sdu.edu.cn [National Glycoengineering Research Center, Shandong University, Jinan 250100 (China); Cui, Fu-Zhai, E-mail: cuifz@mail.tsinghua.edu.cn [Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2014-12-01

    The nHAC/CSH composite is an injectable bone repair material with controllable injectability and self-setting properties prepared by introducing calcium sulfate hemihydrate (CSH) into mineralized collagen (nHAC). When mixed with water, the nHAC/CSH composites can be transformed into mineralized collagen/calcium sulfate dihydrate (nHAC/CSD) composites. The nHAC/CSD composites have good biocompatibility and osteogenic capability. Considering that the degradation behavior of bone repair material is another important factor for its clinical applications, the degradability of nHAC/CSD composites was studied. The results showed that the degradation ratio of the nHAC/CSD composites with lower nHAC content increased with the L/S ratio increase of injectable materials, but the variety of L/S ratio had no significant effect on the degradation ratio of the nHAC/CSD composites with higher nHAC content. Increasing nHAC content in the composites could slow down the degradation of nHAC/CSD composite. Setting accelerator had no significant effect on the degradability of nHAC/CSD composites. In vivo histological analysis suggests that the degradation rate of materials can match the growth rate of new mandibular bone tissues in the implanted site of rabbit. The regulable degradability of materials resulting from the special prescriptions of injectable nHAC/CSH composites will further improve the workability of nHAC/CSD composites. - Highlights: • The nHAC/CSH composite can be as an injectable bone repair material. • The L/S ratio and nHAC content have a significant effect on material degradability. • The degradability of bone materials can be regulated to match tissue repair. • The regulable degradability will further improve the workability of bone materials.

  7. Novel ceramic bone replacement material CeraBall seeded with human mesenchymal stem cells.

    NARCIS (Netherlands)

    Douglas, T.E.L.; Liu, Q.; Humpe, A.; Wiltfang, J.; Sivananthan, S.; Warnke, P.H.

    2010-01-01

    OBJECTIVES: Hydroxyapatite (HA) and tricalcium phosphate (TCP) are two very common ceramic materials for bone replacement. A recently developed material for bone replacement is CeraBall, which is a mixed HA-TCP scaffold available as porous spherical scaffolds of diameter 4 and 6 mm. Before their use

  8. Aging alters bone-fat reciprocity by shifting in vivo mesenchymal precursor cell fate towards an adipogenic lineage.

    Science.gov (United States)

    Singh, Lakshman; Brennan, Tracy A; Russell, Elizabeth; Kim, Jung-Hoon; Chen, Qijun; Brad Johnson, F; Pignolo, Robert J

    2016-04-01

    Bone marrow derived mesenchymal progenitor cells (MPCs) play an important role in bone homeostasis. Age-related changes occur in bone resulting in a decrease in bone density and a relative increase in adipocity. Although in vitro studies suggest the existence of an age-related lineage switch between osteogenic and adipogenic fates, stem cell and microenvironmental contributions to this process have not been elucidated in vivo. In order to study the effects of MPC and microenvironmental aging on functional engraftment and lineage switching, transplantation studies were performed under non-myeloablative conditions in old recipients, with donor MPCs derived from young and old green fluorescent protein (GFP) transgenic mice. Robust engraftment by young MPCs or their progeny was observed in the marrow, bone-lining region and in the matrix of young recipients; however, significantly lower engraftment was seen at the same sites in old recipients transplanted with old MPCs. Differentiation of transplanted MPCs strongly favored adipogenesis over osteogenesis in old recipients irrespective of MPC donor age, suggesting that microenvironmental alterations that occur with in vivo aging are predominately responsible for MPC lineage switching. These data indicate that aging alters bone-fat reciprocity and differentiation of mesenchymal progenitors towards an adipogenic fate.

  9. Bone graft materials in fixation of orthopaedic implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan

    2013-01-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many...... the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking...... bone and includes bone collagen, morphogenetic proteins and growth factors. The combination of DBM with CB and with allograft might improve the healing potential of these grafts around non-cemented orthopaedic implants and thereby the implant fixation. Study I investigates the effect of HA...

  10. The Effect of Altering the Mechanical Loading Environment on the Expression of Bone Regenerating Molecules in Cases of Distraction Osteogenesis

    Directory of Open Access Journals (Sweden)

    Mohammad M Alzahrani

    2014-12-01

    Full Text Available Distraction osteogenesis (DO is a surgical technique where gradual and controlled separation of two bony fragments following an osteotomy leads to the induction of new bone formation in the distracted gap. DO is used for limb lengthening, correction of bony deformities and the replacement of bone loss secondary to infection, trauma and tumors. Although DO gives satisfactory results in most cases, one major drawback of this technique is the prolonged period of time the external fixator has to be kept on until the newly formed bone consolidates thus leading to numerous complications. Numerous attempts at accelerating bone formation during DO have been reported. One specific approach is manipulation of the mechanical environment during DO by applying changes in the standard protocol of distraction. Attempts at changing this mechanical environment led to mixed results. Increasing the rate or applying acute distraction, led to poor bone formation in the distracted zone. On the other hand, the addition of compressive forces (such as weight bearing, alternating distraction with compression or by over-lengthening and then shortening has been reported to increase bone formation. It still remains unclear why these alterations may lead to changes in bone formation. While the cellular and molecular changes occurring during the standard DO protocol, specifically increased expression of transforming growth factor-β1, platelet derived growth factor, insulin-like growth factor, basic fibroblast growth factor, vascular endothelial growth factor, and bone morphogenic proteins have been extensively investigated, the literature is sparse on the changes occurring when this protocol is altered. It is the purpose of this article to review the pertinent literature on the changes in the expression of various proteins and molecules as a result of changes in the mechanical loading technique in DO and try to define potential future research directions.

  11. A perfusion bioreactor system efficiently generates cell‐loaded bone substitute materials for addressing critical size bone defects

    Science.gov (United States)

    Kleinhans, Claudia; Mohan, Ramkumar Ramani; Vacun, Gabriele; Schwarz, Thomas; Haller, Barbara; Sun, Yang; Kahlig, Alexander; Kluger, Petra; Finne‐Wistrand, Anna; Walles, Heike

    2015-01-01

    Abstract Critical size bone defects and non‐union fractions are still challenging to treat. Cell‐loaded bone substitutes have shown improved bone ingrowth and bone formation. However, a lack of methods for homogenously colonizing scaffolds limits the maximum volume of bone grafts. Additionally, therapy robustness is impaired by heterogeneous cell populations after graft generation. Our aim was to establish a technology for generating grafts with a size of 10.5 mm in diameter and 25 mm of height, and thus for grafts suited for treatment of critical size bone defects. Therefore, a novel tailor‐made bioreactor system was developed, allowing standardized flow conditions in a porous poly(L‐lactide‐co‐caprolactone) material. Scaffolds were seeded with primary human mesenchymal stem cells derived from four different donors. In contrast to static experimental conditions, homogenous cell distributions were accomplished under dynamic culture. Additionally, culture in the bioreactor system allowed the induction of osteogenic lineage commitment after one week of culture without addition of soluble factors. This was demonstrated by quantitative analysis of calcification and gene expression markers related to osteogenic lineage. In conclusion, the novel bioreactor technology allows efficient and standardized conditions for generating bone substitutes that are suitable for the treatment of critical size defects in humans. PMID:26011163

  12. A perfusion bioreactor system efficiently generates cell-loaded bone substitute materials for addressing critical size bone defects.

    Science.gov (United States)

    Kleinhans, Claudia; Mohan, Ramkumar Ramani; Vacun, Gabriele; Schwarz, Thomas; Haller, Barbara; Sun, Yang; Kahlig, Alexander; Kluger, Petra; Finne-Wistrand, Anna; Walles, Heike; Hansmann, Jan

    2015-09-01

    Critical size bone defects and non-union fractions are still challenging to treat. Cell-loaded bone substitutes have shown improved bone ingrowth and bone formation. However, a lack of methods for homogenously colonizing scaffolds limits the maximum volume of bone grafts. Additionally, therapy robustness is impaired by heterogeneous cell populations after graft generation. Our aim was to establish a technology for generating grafts with a size of 10.5 mm in diameter and 25 mm of height, and thus for grafts suited for treatment of critical size bone defects. Therefore, a novel tailor-made bioreactor system was developed, allowing standardized flow conditions in a porous poly(L-lactide-co-caprolactone) material. Scaffolds were seeded with primary human mesenchymal stem cells derived from four different donors. In contrast to static experimental conditions, homogenous cell distributions were accomplished under dynamic culture. Additionally, culture in the bioreactor system allowed the induction of osteogenic lineage commitment after one week of culture without addition of soluble factors. This was demonstrated by quantitative analysis of calcification and gene expression markers related to osteogenic lineage. In conclusion, the novel bioreactor technology allows efficient and standardized conditions for generating bone substitutes that are suitable for the treatment of critical size defects in humans.

  13. [Reaction of bone tissue elements on synthetic bioresorbable materials based on lactic and glycolic acids].

    Science.gov (United States)

    Kulakov, A A; Grigor'ian, A S

    2014-01-01

    The aim of the study was to evaluate the adverse effects of synthetic polymeric bioresorbable materials based on lactic and glycolic acids on the bone tissue. The study was carried-out on 40 Wister-line rats. Four types of bioresorbable polymeric materials were implanted: PolyLactide Glycolide Acid (PLGA), Poly-L-Lactide Acid (PLLA); Poly-96L/4D-Lactide Acid (96/4 PLDLA); Poly-70L/30D-Lactide Acid (70/30 PLDLA). The results showed connective tissue formation (fibrointegration) bordering bone adjacent to implanted materials. This proved the materials to cause pathogenic influence on the bone which mechanisms are described in the article.

  14. Altered composition of bone as triggered by irradiation facilitates the rapid erosion of the matrix by both cellular and physicochemical processes.

    Directory of Open Access Journals (Sweden)

    Danielle E Green

    Full Text Available Radiation rapidly undermines trabecular architecture, a destructive process which proceeds despite a devastated cell population. In addition to the 'biologically orchestrated' resorption of the matrix by osteoclasts, physicochemical processes enabled by a damaged matrix may contribute to the rapid erosion of bone quality. 8w male C57BL/6 mice exposed to 5 Gy of Cs(137 γ-irradiation were compared to age-matched control at 2d, 10d, or 8w following exposure. By 10d, irradiation had led to significant loss of trabecular bone volume fraction. Assessed by reflection-based Fourier transform infrared imaging (FTIRI, chemical composition of the irradiated matrix indicated that mineralization had diminished at 2d by -4.3±4.8%, and at 10d by -5.8±3.2%. These data suggest that irradiation facilitates the dissolution of the matrix through a change in the material itself, a conclusion supported by a 13.7±4.5% increase in the elastic modulus as measured by nanoindentation. The decline in viable cells within the marrow of irradiated mice at 2d implies that the immediate collapse of bone quality and inherent increased risk of fracture is not solely a result of an overly-active biologic process, but one fostered by alterations in the material matrix that predisposes the material to erosion.

  15. Altered distributions of bone tissue mineral and collagen properties in women with fragility fractures.

    Science.gov (United States)

    Wang, Zhen Xiang; Lloyd, Ashley A; Burket, Jayme C; Gourion-Arsiquaud, Samuel; Donnelly, Eve

    2016-03-01

    Heterogeneity of bone tissue properties is emerging as a potential indicator of altered bone quality in pathologic tissue. The objective of this study was to compare the distributions of tissue properties in women with and without histories of fragility fractures using Fourier transform infrared (FTIR) imaging. We extended a prior study that examined the relationship of the mean FTIR properties to fracture risk by analyzing in detail the widths and the tails of the distributions of FTIR properties in biopsies from fracture and non-fracture cohorts. The mineral and matrix properties of cortical and trabecular iliac crest tissue were compared in biopsies from women with a history of fragility fracture (+Fx; n=21, age: mean 54±SD 15y) and with no history of fragility fracture (-Fx; n=12, age: 57±5y). A subset of the patients included in the -Fx group were taking estrogen-plus-progestin hormone replacement therapy (HRT) (-Fx+HRT n=8, age: 58±5y) and were analyzed separately from patients with no history of HRT (-Fx-HRT n=4, age: 56±7y). When the FTIR parameter mean values were examined by treatment group, the trabecular tissue of -Fx-HRT patients had a lower mineral:matrix ratio (M:M) and collagen maturity (XLR) than that of -Fx+HRT patients (-22% M:M, -18% XLR) and +Fx patients (-17% M:M, -18% XLR). Across multiple FTIR parameters, tissue from the -Fx-HRT group had smaller low-tail (5th percentile) values than that from the -Fx+HRT or +Fx groups. In trabecular collagen maturity and crystallinity (XST), the -Fx-HRT group had smaller low-tail values than those in the -Fx+HRT group (-16% XLR, -5% XST) and the +Fx group (-17% XLR, -7% XST). The relatively low values of trabecular mineral:matrix ratio and collagen maturity and smaller low-tail values of collagen maturity and crystallinity observed in the -Fx-HRT group are characteristic of younger tissue. Taken together, our data suggest that the presence of newly formed tissue that includes small/imperfect crystals

  16. Bone graft materials in fixation of orthopaedic implants in sheep.

    Science.gov (United States)

    Babiker, Hassan

    2013-07-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many orthopaedic procedures, whereas allograft is the gold standard by replacement of extensive bone loss. However, the use of autograft is associated with donor site morbidity, especially chronic pain. In addition, the limited supply is a significant clinical challenge. Limitations in the use of allograft include the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking skeletal bones. The osteoconductive properties of the composite might be improved by adding bone marrow aspirate (BMA), which can be harvested during surgery. Other alternatives to bone graft are demineralised bone matrix (DBM) and human cancellous bone (CB). DBM is prepared by acid extraction of human bone and includes bone collagen, morphogenetic proteins and growth factors. The combination of DBM with CB and with allograft might improve the healing potential of these grafts around non-cemented orthopaedic implants and thereby the implant fixation. Study I investigates the effect of HA/Collagen composite alone and in combination with BMA on the early fixation of porous coated titanium implants. In addition, the study compares also the effect of autograft with the gold standard allograft. By using a sheep model, the implants were inserted in the trabecular bone of femoral condyles. The test biomaterials were placed in a well defined peri-implant gap. After the observation period, the bone-implant specimens were harvested and evaluated mechanically by a destructive push

  17. Reduced bone mineral density and altered bone turnover markers in patients with non-cirrhotic chronic hepatitis B or C infection

    Institute of Scientific and Technical Information of China (English)

    Ingolf Schiefke; Andreas Fach; Marcus Wiedmann; Andreas V. Aretin; Eva Schenker; Gudrun Borte; Manfred Wiese; Joachim Moessner

    2005-01-01

    AIM: Previous studies suggest that loss of bone mineral density (BMD) frequently occurs in patients with chronic viral liver disease, presenting with histologically proven liver cirrhosis. However, little is known about the occurrence of bone disease in non-cirrhotic patients with chronic hepatitis B or C. Therefore, it was the aim of this study to evaluate this particular population for BMD and bone turnover markers.METHODS: Biochemical markers of bone turnover and BMD were measured in 43 consecutive patients with HCV (n = 30)or HBV (n = 13) infection without histological evidence for liver cirrhosis. Mean age was 49 years (range 26-77 years). BMD was measured by dual X-ray absorptiometry in the femoral neck (FN) and the lumbar spine (LS) region. In addition, bone metabolism markers were measured.RESULTS: BMD was lowered in 25 (58%) of the patients with chronic hepatitis B or C (FN: 0.76 (0.53-0.99); LS:0.96 (0.62-1.23) g/cm2). Eight (32%) osteopenic patients were diagnosed with osteoporosis. Bone-specific alkaline phosphatase (P = 0.005) and intact parathyroid hormone (iPTH) (P = 0.001) were significantly elevated in the more advanced stages of fibrosis. Mean 7-score value was lower in patients with chronic hepatitis C as compared to patients suffering from chronic hepatitis B; however, the difference was not statistically significant (P = 0.09).CONCLUSION: There was a significantly reduced BMD in non-cirrhotic patients with chronic hepatitis B or C infection. Alterations of bone metabolism already occurred in advanced liver fibrosis without cirrhosis. According to our results, these secondary effects of chronic viral hepatitis should be further investigated.

  18. Bone Adaptation Around Orthopaedic Implants of Varying Materials

    DEFF Research Database (Denmark)

    Bagge, Mette

    1998-01-01

    The bone adaptation around orthopaedic implants is simulated using a three-dimensional finite element model. The remodeling scheme has its origin in optimization methods, and includes anisotropy and time-dependent loading......The bone adaptation around orthopaedic implants is simulated using a three-dimensional finite element model. The remodeling scheme has its origin in optimization methods, and includes anisotropy and time-dependent loading...

  19. Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    De-Gang Yu; Shao-Bo Nie; Feng-Xiang Liu; Chuan-Long Wu; Bo Tian; Wen-Gang Wang; Xiao-Qing Wang

    2015-01-01

    Background:The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA).However,the characteristics of subchondral bone alterations remain unresolved.The present study aimed to observe the dynamic alterations in the microarchitecture,mineralization,and mechanical properties of subchondral bone during the progression of OA.Methods:A medial meniscal tear (MMT) operation was performed in 128 adult Sprague Dawley rats to induce OA.At 2,4,8,and 12 weeks following the MMT operation,cartilage degeneration was evaluated using toluidine blue O staining,whereas changes in the microarchitecture indices and tissue mineral density (TMD),mineral-to-collagen ratio,and intrinsic mechanical properties of subchondral bone plates (BPs) and trabecular bones (Tbs) were measured using micro-computed tomography scanning,confocal Raman microspectroscopy and nanoindentation testing,respectively.Results:Cartilage degeneration occurred and worsened progressively from 2 to 12 weeks after OA induction.Microarchitecture analysis revealed that the subchondral bone shifted from bone resorption early (reduced trabecular BV/TV,trabecular number,connectivity density and trabecular thickness [Tb.Th],and increased trabecular spacing (Tb.Sp) at 2 and 4 weeks) to bone accretion late (increased BV/TV,Tb.Th and thickness of subchondral bone plate,and reduced Tb.Sp at 8 and 12 weeks).The TMD of both the BP and Tb displayed no significant changes at 2 and 4 weeks but decreased at 8 and 12 weeks.The mineral-to-collagen ratio showed a significant decrease from 4 weeks for the Tb and from 8 weeks for the BP after OA induction.Both the elastic modulus and hardness of the Tb showed a significant decrease from 4 weeks after OA induction.The BP showed a significant decrease in its elastic modulus from 8 weeks and its hardness from 4 weeks.Conclusion:The microarchitecture,mineralization and mechanical properties of subchondral bone changed in a time

  20. The bone matrix protein secreted phosphoprotein 24 kD (Spp24): bone metabolism regulator and starting material for biotherapeutic materials.

    Science.gov (United States)

    Murray, Samuel S; Wang, Jeffrey C; Duarte, Maria Eugenia Leite; Zhao, Ke-Wei; Tian, Haijun; Francis, Timothy; Brochmann Murray, Elsa J

    2015-05-01

    Secreted phosphoprotein 24 kD (Spp24) is a bone matrix protein that appears to be derived primarily from the liver and delivered to other tissues in a protective complex. A significant role in bone growth and turnover is suggested by genetic studies that associate the gene locus (SPP2) with bone mineral density and bone quality. The function of this protein in the normal bone environment is unknown but clues are given by the fact that Spp24, or proteolytic products of Spp24, bind cytokines of the TGF-β superfamily and also activate intracellular signaling pathways. Several potential biotherapeutics have been engineered from this protein including materials that enhance BMP-induced bone healing and, on the other hand, materials that inhibit BMPs in clinical situations where this is called for such as reducing BMP-induced inflammation and inhibiting tumors dependent on BMP autocrine systems. As understanding of the structure and function of this protein increases, more opportunities for rationally developed therapeutics will become apparent.

  1. Preparation and physicochemical properties of scaffold materials of heterogeneous deproteinized bone

    Institute of Scientific and Technical Information of China (English)

    LIU Lei; LI Qi-hong; TANG Kang-lai; YANG Liu; JIAN Yue-kui

    2007-01-01

    Objective:To prepare and observe the physicochemical properties of scaffold materials of heterogeneous deproteinized tissue-engineered bone.Methods:Deproteinized bone was made through a series of physicochemical treatments in pig ribs and analyzed with histological observation,scanning electron microscopy, infrared spectrum, X-ray diffraction and energy dispersive analysis, Kjeldahl determination and mechanics analysis.Results:Interstitial collagen fiber was positive and mucin was negative in deproteinized bone,but,both were positive in fresh bone. Deproteinized bone maintained natural pore network.Its pore size was 472.51 μm±7.02μm and the porosity was 78.15 % ± 6.45 %.The results of infrared spectrum showed that collagen was present in deproteinized bone.Both fresh and deproteinized bone had curve of hydroxyapatite.The Ca/P ratios were 1.71 ±0.95and 1.68 ± 0.76 ( P > 0.05 ),and the protein contents were 26.6% ± 2.23% and 19.1% ± 2.14% (P < 0.05)in fresh and deproteinized bone,respectively.There was no significant difference of destruction load under compression and maximal destruction load between fresh and deproteinized bone (P > 0.05).The elastic modulus was higher in deproteinized bone than that in fresh bone (P < 0.05).Conclusions:Physicochemical properties and mechanic strength of deproteinized tissue-engineered bone meet the demands of ideal scaffold materials. But,its immunogenicity should be observed through further experiments for its clinical applications.

  2. Alterations in osteoclast function and phenotype induced by different inhibitors of bone resorption - implications for osteoclast quality

    Directory of Open Access Journals (Sweden)

    Leeming Diana J

    2010-06-01

    Full Text Available Abstract Background Normal osteoclasts resorb bone by secretion of acid and proteases. Recent studies of patients with loss of function mutations affecting either of these processes have indicated a divergence in osteoclastic phenotypes. These difference in osteoclast phenotypes may directly or indirectly have secondary effects on bone remodeling, a process which is of importance for the pathogenesis of both osteoporosis and osteoarthritis. We treated human osteoclasts with different inhibitors and characterized their resulting function. Methods Human CD14 + monocytes were differentiated into mature osteoclasts using RANKL and M-CSF. The osteoclasts were cultured on bone in the presence or absence of various inhibitors: Inhibitors of acidification (bafilomycin A1, diphyllin, ethoxyzolamide, inhibitors of proteolysis (E64, GM6001, or a bisphosphonate (ibandronate. Osteoclast numbers and bone resorption were monitored by measurements of TRACP activity, the release of calcium, CTX-I and ICTP, as well as by counting resorption pits. Results All inhibitors of acidification were equally potent with respect to inhibition of both organic and inorganic resorption. In contrast, inhibition of proteolysis by E64 potently reduced organic resorption, but only modestly suppressed inorganic resorption. GM6001 alone did not greatly affect bone resorption. However, when GM6001 and E64 were combined, a complete abrogation of organic bone resorption was observed, without a great effect on inorganic resorption. Ibandronate abrogated both organic and inorganic resorption at all concentrations tested [0.3-100 μM], however, this treatment dramatically reduced TRACP activity. Conclusions We present evidence highlighting important differences with respect to osteoclast function, when comparing the different types of osteoclast inhibitors. Each class of osteoclast inhibitors will lead to different alterations in osteoclast quality, which secondarily may lead to different

  3. Mineralized polymer composites as biogenic bone substitute material

    Science.gov (United States)

    Shah, Rushita; Saha, Nabanita; Kitano, Takeshi; Saha, Petr

    2015-05-01

    Mineralized polymer composites (MPC) are recognized as potential fillers of bone defects. Though bioceramics exhibits quite a good bone-bonding and vascularization, it is considered to be too stiff and brittle for using alone. Thus, the use of polymer scaffold instead of bioceramics has several advantages including combining the osteoconductivity and bone-bonding potential of the inorganic phase with the porosity and interconnectivity of the three-dimensional construction. Aiming the advantages of ceramic-polymer composite scaffolds, the calcium carbonate (CaCO3) based biomineralized scaffold was prepared, where the PVP-CMC hydrogel was used as an extracellular matrix. This paper is reported about the morphology, swelling trend (in physiological solution) and viscoelastic behavior of (90 min mineralized) MPC. The dry MPC are off-white, coarse in texture, comparatively less flexible than the original PVP-CMC based hydrogel film, and the deposition of granular structures on the surface of the hydrogel film confirms about the development of biomineralized scaffold/polymer composites. Irrespective of thickness, the dry MPC shows higher values of swelling ratio within 30 min, which varies between 200-250 approximately. The dynamic viscoelastic nature of freshly prepared MPC was investigated applying 1% and 10% strain. At higher strain the viscoelastic moduli (G' and G") show significant change, and the nature of MPC turns from elastic to viscous. Based on the observed basic properties, the MPC (calcite based polymer composites) can be recommended for the treatment of adyanamic bone disorder.

  4. Ocean acidification alters the material properties of Mytilus edulis shells.

    Science.gov (United States)

    Fitzer, Susan C; Zhu, Wenzhong; Tanner, K Elizabeth; Phoenix, Vernon R; Kamenos, Nicholas A; Cusack, Maggie

    2015-02-01

    Ocean acidification (OA) and the resultant changing carbonate saturation states is threatening the formation of calcium carbonate shells and exoskeletons of marine organisms. The production of biominerals in such organisms relies on the availability of carbonate and the ability of the organism to biomineralize in changing environments. To understand how biomineralizers will respond to OA the common blue mussel, Mytilus edulis, was cultured at projected levels of pCO2 (380, 550, 750, 1000 µatm) and increased temperatures (ambient, ambient plus 2°C). Nanoindentation (a single mussel shell) and microhardness testing were used to assess the material properties of the shells. Young's modulus (E), hardness (H) and toughness (KIC) were measured in mussel shells grown in multiple stressor conditions. OA caused mussels to produce shell calcite that is stiffer (higher modulus of elasticity) and harder than shells grown in control conditions. The outer shell (calcite) is more brittle in OA conditions while the inner shell (aragonite) is softer and less stiff in shells grown under OA conditions. Combining increasing ocean pCO2 and temperatures as projected for future global ocean appears to reduce the impact of increasing pCO2 on the material properties of the mussel shell. OA may cause changes in shell material properties that could prove problematic under predation scenarios for the mussels; however, this may be partially mitigated by increasing temperature.

  5. A nano-hydroxyapatite--pullulan/dextran polysaccharide composite macroporous material for bone tissue engineering.

    Science.gov (United States)

    Fricain, Jean Christophe; Schlaubitz, Silke; Le Visage, Catherine; Arnault, Isabelle; Derkaoui, Sidi Mohammed; Siadous, Robin; Catros, Sylvain; Lalande, Charlotte; Bareille, Reine; Renard, Martine; Fabre, Thierry; Cornet, Sandro; Durand, Marlène; Léonard, Alain; Sahraoui, Nouredine; Letourneur, Didier; Amédée, Joëlle

    2013-04-01

    Research in bone tissue engineering is focused on the development of alternatives to allogenic and autologous bone grafts that can stimulate bone healing. Here, we present scaffolds composed of the natural hydrophilic polysaccharides pullulan and dextran, supplemented or not with nanocrystalline hydroxyapatite particles (nHA). In vitro studies revealed that these matrices induced the formation of multicellular aggregates and expression of early and late bone specific markers with human bone marrow stromal cells in medium deprived of osteoinductive factors. In absence of any seeded cells, heterotopic implantation in mice and goat, revealed that only the composite macroporous scaffold (Matrix + nHA) (i) retained subcutaneously local growth factors, including Bone Morphogenetic Protein 2 (BMP2) and VEGF165, (ii) induced the deposition of a biological apatite layer, (iii) favored the formation of a dense mineralized tissue subcutaneously in mice, as well osteoid tissue after intramuscular implantation in goat. The composite scaffold was thereafter implanted in orthotopic preclinical models of critical size defects, in small and large animals, in three different bony sites, i.e. the femoral condyle of rat, a transversal mandibular defect and a tibial osteotomy in goat. The Matrix + nHA induced a highly mineralized tissue in the three models whatever the site of implantation, as well as osteoid tissue and bone tissue regeneration in direct contact to the matrix. We therefore propose this composite matrix as a material for stimulating bone cell differentiation of host mesenchymal stem cells and bone formation for orthopedic and maxillofacial surgical applications.

  6. Effects of altered crystalline structure and increased initial compressive strength of calcium sulfate bone graft substitute pellets on new bone formation.

    Science.gov (United States)

    Urban, Robert M; Turner, Thomas M; Hall, Deborah J; Infanger, Susan I; Cheema, Naveed; Lim, Tae-Hong; Moseley, Jon; Carroll, Michael; Roark, Michael

    2004-01-01

    A new, modified calcium sulfate has been developed with a different crystalline structure and a compressive strength similar to many calcium phosphate materials, but with a resorption profile only slightly slower than conventional surgical-grade calcium sulfate. A canine bilateral defect model was used to compare restoration of defects treated with the modified calcium sulfate compared to treatment using conventional calcium sulfate pellets after 6, 13, and 26 weeks. The modified calcium sulfate pellets were as effective as conventional calcium sulfate pellets with regard to the area fraction and compressive strength of newly formed bone in the treated bone defects. Mechanical testing demonstrated that the initial compressive strength of the modified material was increased nearly three-fold compared to that of conventional surgical-grade calcium sulfate. This increase potentially allows for its use in a broader range of clinical applications, such as vertebral and subchondral defects.

  7. Caloric restriction and the adipokine leptin alter the SDF-1 signaling axis in bone marrow and in bone marrow derived mesenchymal stem cells.

    Science.gov (United States)

    Periyasamy-Thandavan, Sudharsan; Herberg, Samuel; Arounleut, Phonepasong; Upadhyay, Sunil; Dukes, Amy; Davis, Colleen; Johnson, Maribeth; McGee-Lawrence, Meghan; Hamrick, Mark W; Isales, Carlos M; Hill, William D

    2015-07-15

    Growing evidence suggests that the chemokine stromal cell-derived factor-1 (SDF-1) is essential in regulating bone marrow (BM) derived mesenchymal stromal/stem cell (BMSC) survival, and differentiation to either a pro-osteogenic or pro-adipogenic fate. This study investigates the effects of caloric restriction (CR) and leptin on the SDF-1/CXCR4 axis in bone and BM tissues in the context of age-associated bone loss. For in vivo studies, we collected bone, BM cells and BM interstitial fluid from 12 and 20 month-old C57Bl6 mice fed ad-libitum (AL), and 20-month-old mice on long-term CR with, or without, intraperitoneal injection of leptin for 10 days (10 mg/kg). To mimic conditions of CR in vitro, 18 month murine BMSCs were treated with (1) control (Ctrl): normal proliferation medium, (2) nutrient restriction (NR): low glucose, low serum medium, or (3) NR + leptin: NR medium + 100 ng/ml leptin for 6-48 h. In BMSCs both protein and mRNA expression of SDF-1 and CXCR4 were increased by CR and CR + leptin. In contrast, the alternate SDF-1 receptor CXCR7 was decreased, suggesting a nutrient signaling mediated change in SDF-1 axis signaling in BMSCs. However, in bone SDF-1, CXCR4 and 7 gene expression increase with age and this is reversed with CR, while addition of leptin returns this to the "aged" level. Histologically bone formation was lower in the calorically restricted mice and BM adipogenesis increased, both effects were reversed with the 10 day leptin treatment. This suggests that in bone CR and leptin alter the nutrient signaling pathways in different ways to affect the local action of the osteogenic cytokine SDF-1. Studies focusing on the molecular interaction between nutrient signaling by CR, leptin and SDF-1 axis may help to address age-related musculoskeletal changes.

  8. Age- and gender-related distribution of bone mineral density and mechanical properties of the proximal humerus; Alters- und geschlechtsabhaengige Knochenmineraldichteverteilung und mechanische Eigenschaften des proximalen Humerus

    Energy Technology Data Exchange (ETDEWEB)

    Lill, H.; Hepp, P.; Korner, J.; Josten, C. [Klinik fuer Unfall- und Wiederherstellungschirurgie, Univ. Leipzig (Germany); Gowin, W. [Center of Muscle and Bone Research, Klinik fuer Radiologie und Nuklearmedizin, Universitaetsklinikum Benjamin Franklin, Freie Univ. Berlin (Germany); Oestmann, J.W. [Klinik fuer Radiologie, Charite, Virchow-Klinikum, Humboldt Univ., Berlin (Germany); Haas, N.P.; Duda, G.N. [Klinik fuer Unfall- und Wiederherstellungschirurgie, Charite, Virchow-Klinikum Humboldt-Univ. Berlin (Germany)

    2002-12-01

    Purpose: To evaluate age- and gender-related mechanical properties and bone mineral density (BMD) of the proximal humerus at different levels and regions. Materials and methods: Mechanical indentation testing, DXA, QCT, pQCT and the radiogrammetry (Cortical Index, CI) were carried out in 70 freshly harvested humeri from 46 human cadavers (23 females, 23-males; median age 70.5 years). Results: In the female group, a high correlation between age and BMD was found ({rho}=0.62 to -0.70, p<0.01) with statistically significant differences between specimens of patients 69 years or younger, and 70 years or older (p<0.05). In the group of female specimens of age 70 years or older, BMD values were found to be significantly lower compared to their male counterparts (p<0.05). Regardless of the specimen's age, the highest BMD and bone strength were found in the proximal aspect and in the medial and dorsal regions of the proximal humerus. Conclusion: These findings provide an insight into the fracture mechanism of the proximal humerus and should be the basis for designing structure-oriented implants with improved implant-bone stability in osteoporotic patients. (orig.) [German] Ziel: Das Ziel der vorliegenden Studie war die alters- und geschlechtsspezifische Analyse der mechanischen Eigenschaften und der Knochenmineraldichte (BMD) des proximalen Humerus in verschiedenen Hoehen und Regionen. Methoden: Folgende Verfahren wurden angewandt: Mechanische Indentation Testung, DXA, QCT, pQCT und die Radiogrammetrie (Cortical Index, CI). Die Untersuchungen wurden an 70 frischen Humeri von 46 humanen Praeparaten (23 weiblich, 23 maennlich; Alter median: 70,5 Jahre) durchgefuehrt. Ergebnisse: In der Gruppe der weiblichen Humeri fand sich eine hohe Korrelation zwischen Alter und Knochenmineraldichte ({rho}=-0,62 to -0,70 p<0,01) mit statistisch signifikanten Unterschieden zwischen Praeparaten juenger als 69 Jahre und aelter als 70 Jahre (p<0.05). In der Gruppe der weiblichen Praeparate

  9. Alteration of blood clot structures by interleukin-1 beta in association with bone defects healing

    Science.gov (United States)

    Wang, Xin; Friis, Thor E.; Masci, Paul P.; Crawford, Ross W.; Liao, Wenbo; Xiao, Yin

    2016-01-01

    The quality of hematomas are crucial for successful early bone defect healing, as the structure of fibrin clots can significantly influence the infiltration of cells, necessary for bone regeneration, from adjacent tissues into the fibrin network. This study investigated if there were structural differences between hematomas from normal and delayed healing bone defects and whether such differences were linked to changes in the expression of IL-1β. Using a bone defect model in rats, we found that the hematomas in the delayed healing model had thinner fibers and denser clot structures. Moreover, IL-1β protein levels were significantly higher in the delayed healing hematomas. The effects of IL-1β on the structural properties of human whole blood clots were evaluated by thrombelastograph (TEG), scanning electronic microscopy (SEM), compressive study, and thrombolytic assays. S-nitrosoglutathione (GSNO) was applied to modulate de novo hematoma structure and the impact on bone healing was evaluated in the delayed healing model. We found that GSNO produced more porous hematomas with thicker fibers and resulted in significantly enhanced bone healing. This study demonstrated that IL-1β and GSNO had opposing effects on clot architecture, the structure of which plays a pivotal role in early bone healing. PMID:27767056

  10. Characterization of a Composite Material to Mimic Human Cranial Bone

    Science.gov (United States)

    2015-09-01

    a general population. These file formats can be sent directly to additive manufacturing machines , generically referred to as 3-D printers, to...Illustration of the SLA additive manufacturing process. The SLA machine used in this study to manufacture specimens was a Viper Si (3D Systems, Rock...architectures while possessing physical and mechanical characteristics similar to that of bone. We are utilizing additive manufacturing , more generally

  11. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  12. The Effects of Surface Properties of Nanostructured Bone Repair Materials on Their Performances

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2015-01-01

    Full Text Available Nanotechnology has been expected to be an extraordinarily promising method for bone repair. Meanwhile, the promise of nanobiomaterials for therapeutic applications has been widely reported, and a lot of studies have been made in terms of repairing bone using nanomaterials accompanied by rapid development of nanotechnology. Compared with conventional biomaterials, nanostructured implants have been shown to possess positive effects on cellular functions because of their unique surface properties, such as nanotopography, increased wettability, larger surface area, and microenvironment similar to extracellular matrix. Moreover, many positive cellular responses have been found to take place at the interface between nanostructured implants and host bone. In this paper, we will give a review about the effects of surface properties of nanostructured bone repair materials on their performances in terms of several aspects and a detailed interpretation or introduction on the specific cellular recognitions at the interface between nanostructured implants and host bone.

  13. [Effect of periodontal regeneration using collagen-coated synthetic bone implant materials. Histopathological study].

    Science.gov (United States)

    Sugaya, A

    1989-09-01

    Granulated artificial bone implant materials such as hydroxyapatite (HAP) and tricalcium phosphate (TCP) have been frequently used in attempts to restore periodontal tissue lost as a result periodontitis. However, these materials are considered insufficient for the maintenance and stability of granules at sites losing bone, for active bone formation, or for periodontal ligament regeneration. We have now developed a complex consisting of HAP or TCP coated with atelocollagen (which has recently received attention as a biomaterial) and have conducted experiments to determine the effects of this material on the reconstruction of periodontal tissue. Implantations were performed using a HAP-atelocollagen complex, TCP-atelocollagen complex, HAP and TCP at three-wall bone defect sites in experimentally-induced periodontitis in dogs. A control group without the implants was included in the study. Histopathological observations were conducted 2, 4 and 12 weeks after surgery. Compared with the control group, the groups implanted with the complex displayed enhanced maintenance and stability of granules, suppression of epithelial downgrowth, and acceleration of new bone and cementum formation. These results indicate that the implant method using an atelocollagen-coated artificial bone implant material would be useful for periodontal surgical treatment, eliminating some of the disadvantages of conventional implant methods.

  14. A comparative study of zirconium and titanium implants in rat: osseointegration and bone material quality.

    Science.gov (United States)

    Hoerth, Rebecca M; Katunar, María R; Gomez Sanchez, Andrea; Orellano, Juan C; Ceré, Silvia M; Wagermaier, Wolfgang; Ballarre, Josefina

    2014-02-01

    Permanent metal implants are widely used in human medical treatments and orthopedics, for example as hip joint replacements. They are commonly made of titanium alloys and beyond the optimization of this established material, it is also essential to explore alternative implant materials in view of improved osseointegration. The aim of our study was to characterize the implant performance of zirconium in comparison to titanium implants. Zirconium implants have been characterized in a previous study concerning material properties and surface characteristics in vitro, such as oxide layer thickness and surface roughness. In the present study, we compare bone material quality around zirconium and titanium implants in terms of osseointegration and therefore characterized bone material properties in a rat model using a multi-method approach. We used light and electron microscopy, micro Raman spectroscopy, micro X-ray fluorescence and X-ray scattering techniques to investigate the osseointegration in terms of compositional and structural properties of the newly formed bone. Regarding the mineralization level, the mineral composition, and the alignment and order of the mineral particles, our results show that the maturity of the newly formed bone after 8 weeks of implantation is already very high. In conclusion, the bone material quality obtained for zirconium implants is at least as good as for titanium. It seems that the zirconium implants can be a good candidate for using as permanent metal prosthesis for orthopedic treatments.

  15. Antler stiffness in moose (Alces alces): correlated evolution of bone function and material properties?

    Science.gov (United States)

    Blob, Richard W; Snelgrove, Jason M

    2006-09-01

    The material properties of bone can vary considerably among skeletal elements from different parts of the body that serve different functions. However, functional demands placed on a specific type of skeletal element also can vary at a variety of scales, such as between different parts of the element, among individuals of a species, and across species. Variation in bone material properties might be correlated with differing functional demands at any of these scales. In this study we performed three-point bending tests on bone specimens extracted from antlers of moose (Alces alces) to test for three types of variation in bone material stiffness (Young's modulus): within the antler structure, between populations of moose, and between moose and other deer species. Because superficial portions of the antler are exposed to greater bending stress and strain than deeper portions, and because the antler beam (the basal shaft that attaches to the skull) is subjected to greater bending moments than more distal parts of the antler, we predicted that superficial bone and bone from the beam would be stiffer than bone from other parts of the antler. Instead, we identified no significant differences in these comparisons. There were also no significant differences in antler stiffness between moose from Michigan and the Yukon, even though the rapid growth required of antlers from northern latitudes like the Yukon has the potential to compromise bone material properties. However, moose have significantly stiffer antlers (11.6 +/- 0.45 GPa, mean +/- SE) than any other deer in the odocoileine lineage. Moreover, phylogenetic reconstructions of the evolution of antler stiffness in deer indicate a strong potential that high antler stiffness is a derived feature of moose. The unusual palmate shape of moose antlers likely subjects their antler beams to higher bending moments than found in other odocoileines, a factor that may have contributed to the evolutionary divergence of moose antler

  16. Microstructural, densitometric and metabolic variations in bones from rats with normal or altered skeletal states.

    Directory of Open Access Journals (Sweden)

    Andrew N Luu

    Full Text Available BACKGROUND: High resolution μCT, and combined μPET/CT have emerged as non-invasive techniques to enhance or even replace dual energy X-ray absorptiometry (DXA as the current preferred approach for fragility fracture risk assessment. The aim of this study was to assess the ability of µPET/CT imaging to differentiate changes in rat bone tissue density and microstructure induced by metabolic bone diseases more accurately than current available methods. METHODS: Thirty three rats were divided into three groups of control, ovariectomy and vitamin-D deficiency. At the conclusion of the study, animals were subjected to glucose ((18FDG and sodium fluoride (Na(18F PET/CT scanning. Then, specimens were subjected to µCT imaging and tensile mechanical testing. RESULTS: Compared to control, those allocated to ovariectomy and vitamin D deficiency groups showed 4% and 22% (significant increase in (18FDG uptake values, respectively. DXA-based bone mineral density was higher in the vitamin D deficiency group when compared to the other groups (cortical bone, yet μCT-based apparent and mineral density results were not different between groups. DXA-based bone mineral density was lower in the ovariectomy group when compared to the other groups (cancellous bone; yet μCT-based mineral density results were not different between groups, and the μCT-based apparent density results were lower in the ovariectomy group compared to the other groups. CONCLUSION: PET and micro-CT provide an accurate three-dimensional measurement of the changes in bone tissue mineral density, as well as microstructure for cortical and cancellous bone and metabolic activity. As osteomalacia is characterized by impaired bone mineralization, the use of densitometric analyses may lead to misinterpretation of the condition as osteoporosis. In contrast, µCT alone and in combination with the PET component certainly provides an accurate three-dimensional measurement of the changes in both bone

  17. Neutrophil mobilization by surface-glycan altered Th17-skewing bacteria mitigates periodontal pathogen persistence and associated alveolar bone loss.

    Directory of Open Access Journals (Sweden)

    Rajendra P Settem

    Full Text Available Alveolar bone (tooth-supporting bone erosion is a hallmark of periodontitis, an inflammatory disease that often leads to tooth loss. Periodontitis is caused by a select group of pathogens that form biofilms in subgingival crevices between the gums and teeth. It is well-recognized that the periodontal pathogen Porphyromonas gingivalis in these biofilms is responsible for modeling a microbial dysbiotic state, which then initiates an inflammatory response destructive to the periodontal tissues and bone. Eradication of this pathogen is thus critical for the treatment of periodontitis. Previous studies have shown that oral inoculation in mice with an attenuated strain of the periodontal pathogen Tannerella forsythia altered in O-glycan surface composition induces a Th17-linked mobilization of neutrophils to the gingival tissues. In this study, we sought to determine if immune priming with such a Th17-biasing strain would elicit a productive neutrophil response against P. gingivalis. Our data show that inoculation with a Th17-biasing T. forsythia strain is effective in blocking P. gingivalis-persistence and associated alveolar bone loss in mice. This work demonstrates the potential of O-glycan modified Tannerella strains or their O-glycan components for harnessing Th17-mediated immunity against periodontal and other mucosal pathogens.

  18. Comparison about the bone material examination of JIS and ISO; Honezai shiken ni kansuru JIS to ISO no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Sumie.; Yanagi, Kei.; Shimura, Akiharu.; Murohoshi, Shiori. [Japan Testing Center for Construction Materials, Tokyo (Japan)

    1998-12-01

    There are various things in slug bone material and so on manufactured from the macadam, crumble sand. Which crushed rock including gravel, sand to produce in the nature and which was manufactured, and a lightweight bone material and the industry by-product with the bone material used for the concrete. It is necessary with a bone material to grasp the nature of the bone material itself properly to occupy about 70% of the capacity in the concrete and to manufacture the good concrete of the quality from the influence that influence to the various concrete materiality that quality being big. When the quality of a bone material to use for the concrete is confirmed, an examination is being done in accordance with the way of examining it established as the Japanese industry standard in our country. (NEDO)

  19. Surface coatings for improvement of bone cell materials and antimicrobial activities of Ti implants.

    Science.gov (United States)

    Das, Kakoli; Bose, Susmita; Bandyopadhyay, Amit; Karandikar, Balu; Gibbins, Bruce L

    2008-11-01

    Ti surface was modified to simultaneously improve bone cell materials and antimicrobial activities. Titanium surface was first anodized in sodium fluoride and sulfuric acid electrolytic solution to form titania nanotube on the surface to improve the biocompatibility of the surface. Silver was electrodeposited on the titania nanotube surface at 5 V. Silver added titania nanotube surface was tested for compatibility with bone-cell materials interactions using human osteoblast bone cells. The antibacterial effect was studied using Pseudomonas aeruginosa. Our results show that silver-treated titania nanotube surface may provide antibacterial properties to prevent implants against postoperative infections without interference to the attachment and proliferation of bone tissue on titanium, which is commonly used in dental and orthopedic surgical procedures.

  20. Spaceflight-induced bone loss alters failure mode and reduces bending strength in murine spinal segments.

    Science.gov (United States)

    Berg-Johansen, Britta; Liebenberg, Ellen C; Li, Alfred; Macias, Brandon R; Hargens, Alan R; Lotz, Jeffrey C

    2016-01-01

    Intervertebral disc herniation rates are quadrupled in astronauts following spaceflight. While bending motions are main contributors to herniation, the effects of microgravity on the bending properties of spinal discs are unknown. Consequently, the goal of this study was to quantify the bending properties of tail discs from mice with or without microgravity exposure. Caudal motion segments from six mice returned from a 30-day Bion M1 mission and eight vivarium controls were loaded to failure in four-point bending. After testing, specimens were processed using histology to determine the location of failure, and adjacent motion segments were scanned with micro-computed tomography (μCT) to quantify bone properties. We observed that spaceflight significantly shortened the nonlinear toe region of the force-displacement curve by 32% and reduced the bending strength by 17%. Flight mouse spinal segments tended to fail within the growth plate and epiphyseal bone, while controls tended to fail at the disc-vertebra junction. Spaceflight significantly reduced vertebral bone volume fraction, bone mineral density, and trabecular thickness, which may explain the tendency of flight specimens to fail within the epiphyseal bone. Together, these results indicate that vertebral bone loss during spaceflight may degrade spine bending properties and contribute to increased disc herniation risk in astronauts.

  1. Extraction and characterisation of apatite- and tricalcium phosphate-based materials from cod fish bones

    Energy Technology Data Exchange (ETDEWEB)

    Piccirillo, C.; Silva, M.F. [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Porto (Portugal); Pullar, R.C. [Dept. Engenharia de Materiais e Ceramica/CICECO, Universidade de Aveiro, Aveiro (Portugal); Braga da Cruz, I. [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Porto (Portugal); WeDoTech, CiDEB/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Porto (Portugal); Jorge, R. [WeDoTech, CiDEB/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Porto (Portugal); Pintado, M.M.E. [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Porto (Portugal); Castro, P.M.L., E-mail: plcastro@porto.ucp.pt [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Porto (Portugal)

    2013-01-01

    Apatite- and tricalcium phosphate-based materials were produced from codfish bones, thus converting a waste by-product from the food industry into high added-valued compounds. The bones were annealed at temperatures between 900 and 1200 Degree-Sign C, giving a biphasic material of hydroxyapatite and tricalcium phosphate (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2} and {beta}-Ca(PO{sub 4}){sub 3}) with a molar proportion of 75:25, a material widely used in biomedical implants. The treatment of the bones in solution prior to their annealing changed the composition of the material. Single phase hydroxyapatite, chlorapatite (Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}) and fluorapatite (Ca{sub 10}(PO{sub 4}){sub 6}F{sub 2}) were obtained using CaCl{sub 2} and NaF solutions, respectively. The samples were analysed by several techniques (X-ray diffraction, infrared spectroscopy, scanning electron microscopy and differential thermal/thermogravimetric analysis) and by elemental analyses, to have a more complete understanding of the conversion process. Such compositional modifications have never been performed before for these materials of natural origin to tailor the relative concentrations of elements. This paper shows the great potential for the conversion of this by-product into highly valuable compounds for biomedical applications, using a simple and effective valorisation process. - Highlights: Black-Right-Pointing-Pointer Apatite and calcium phosphate compounds extraction from cod fish bones Black-Right-Pointing-Pointer Bone calcination: biphasic material hydroxyapatite-calcium phosphate production Black-Right-Pointing-Pointer Bone pre-treatments in solution change the material composition. Black-Right-Pointing-Pointer Single phase materials (hydroxy-, chloro- or fluoroapatite) are obtained. Black-Right-Pointing-Pointer Concentration of other elements (Na, F, Cl) suitable for biomedical applications.

  2. Toward accelerated bone regeneration by altering poly(D,L-lactic-co-glycolic) acid porogen content in calcium phosphate cement.

    Science.gov (United States)

    van Houdt, C I A; Preethanath, R S; van Oirschot, B A J A; Zwarts, P H W; Ulrich, D J O; Anil, S; Jansen, J A; van den Beucken, J J J P

    2016-02-01

    This work aimed to compare in vitro degradation of dense PLGA microspheres and milled PLGA particles as porogens within CPC, considering that the manufacturing of milled PLGA is more cost-effective when compared with PLGA microspheres. Additionally, we aimed to examine the effect of porogen amount within CPC/PLGA on degradation and bone formation. Our in vitro results showed no differences between both forms of PLGA particles (as porogens in CPC; spherical for microspheres, irregular for milled) regarding morphology, porosity, and degradation. Using milled PLGA as porogens within CPC/PLGA, we evaluated the effect of porogen amount on degradation and bone forming capacity in vivo. Titanium landmarks surrounded by CPC/PLGA with 30 and 50 wt % PLGA, were implanted in forty femoral bone defects of twenty male Wistar rats. Histomorphometrical results showed a significant temporal decrease in the amount of CPC, for both formulas, and confirmed that 50 wt % PLGA degrades faster than 30 wt%, and allows for a 1.5-fold higher amount of newly formed bone. Taken together, this study demonstrated that (i) milled PLGA particles perform equal to PLGA microspheres, and (ii) tuning of the PLGA content in CPC/PLGA is a feasible approach to leverage material degradation and bone formation.

  3. A non-linear homogeneous model for bone-like materials under compressive load.

    Science.gov (United States)

    Mengoni, M; Voide, R; de Bien, C; Freichels, H; Jérôme, C; Léonard, A; Toye, D; Müller, R; van Lenthe, G H; Ponthot, J P

    2012-02-01

    Finite element (FE) models accurately compute the mechanical response of bone and bone-like materials when the models include their detailed microstructure. In order to simulate non-linear behavior, which currently is only feasible at the expense of extremely high computational costs, coarser models can be used if the local morphology has been linked to the apparent mechanical behavior. The aim of this paper is to implement and validate such a constitutive law. This law is able to capture the non-linear structural behavior of bone-like materials through the use of fabric tensors. It also allows for irreversible strains using an elastoplastic material model incorporating hardening. These features are expressed in a constitutive law based on the anisotropic continuum damage theory coupled with isotropic elastoplasticity in a finite strain framework. This material model was implemented into metafor (LTAS-MNNL, University of Liège, Belgium), a non-linear FE software. The implementation was validated against experimental data of cylindrical samples subjected to compression. Three materials with bone-like microstructure were tested: aluminum foams of variable density (ERG, Oakland, CA, USA), polylactic acid foam (CERM, University of Liège, Liège, Belgium), and cancellous bone tissue of a deer antler (Faculty of Veterinary Medicine, University of Liège, Liège, Belgium).

  4. Loss of VHL in mesenchymal progenitors of the limb bud alters multiple steps of endochondral bone development.

    Science.gov (United States)

    Mangiavini, Laura; Merceron, Christophe; Araldi, Elisa; Khatri, Richa; Gerard-O'Riley, Rita; Wilson, Tremika LeShan; Rankin, Erinn B; Giaccia, Amato J; Schipani, Ernestina

    2014-09-01

    Adaptation to low oxygen tension (hypoxia) is a critical event during development. The transcription factors Hypoxia Inducible Factor-1α (HIF-1α) and HIF-2α are essential mediators of the homeostatic responses that allow hypoxic cells to survive and differentiate. Von Hippel-Lindau protein (VHL) is the E3 ubiquitin ligase that targets HIFs to the proteasome for degradation in normoxia. We have previously demonstrated that the transcription factor HIF-1α is essential for survival and differentiation of growth plate chondrocytes, whereas HIF-2α is not necessary for fetal growth plate development. We have also shown that VHL is important for endochondral bone development, since loss of VHL in chondrocytes causes severe dwarfism. In this study, in order to expand our understanding of the role of VHL in chondrogenesis, we conditionally deleted VHL in mesenchymal progenitors of the limb bud, i.e. in cells not yet committed to the chondrocyte lineage. Deficiency of VHL in limb bud mesenchyme does not alter the timely differentiation of mesenchymal cells into chondrocytes. However, it causes structural collapse of the cartilaginous growth plate as a result of impaired proliferation, delayed terminal differentiation, and ectopic death of chondrocytes. This phenotype is associated to delayed replacement of cartilage by bone. Notably, loss of HIF-2α fully rescues the late formation of the bone marrow cavity in VHL mutant mice, though it does not affect any other detectable abnormality of the VHL mutant growth plates. Our findings demonstrate that VHL regulates bone morphogenesis as its loss considerably alters size, shape and overall development of the skeletal elements.

  5. Effects of Materials of Cementless Femoral Stem on the Functional Adaptation of Bone

    Institute of Scientific and Technical Information of China (English)

    He Gong; Wei Wu; Juan Fang; Xin Dong; Meisheng Zhao; Tongtong Guo

    2012-01-01

    The objective of this paper is to identify the effects of materials of cementless femoral stem on the functional adaptive behaviors of bone.The remodeling behaviors of a two-dimensional simplified model of cementless hip prosthesis with stiff stem,flexible 'iso-elastic' stem,one-dimensional Functionally Graded Material (FGM) stem and two-dimensional FGM stem for the period of four years after prosthesis replacement were quantified by incorporating the bone remodeling algorithm with finite element analysis.The distributions of bone density,von Mises stress,and interface shear stress were obtained.The results show that two-dimensional FGM stem may produce more mechanical stimuli and more uniform interface shear stress compared with the stems made of other materials,thus the host bone is well preserved.Accordingly,the two-dimensional FGM stem is an appropriate femoral implant from a biomechanical point of view.The numerical simulation in this paper can provide a quantitative computational paradigm for the changes of bone morphology caused by implants,which can help to improve the design of implant to reduce stress shielding and the risk of bone-prosthesis interface failure.

  6. In vivo tungsten exposure alters B-cell development and increases DNA damage in murine bone marrow.

    Science.gov (United States)

    Kelly, Alexander D R; Lemaire, Maryse; Young, Yoon Kow; Eustache, Jules H; Guilbert, Cynthia; Molina, Manuel Flores; Mann, Koren K

    2013-02-01

    High environmental tungsten levels were identified near the site of a childhood pre-B acute lymphoblastic leukemia cluster; however, a causal link between tungsten and leukemogenesis has not been established. The major site of tungsten deposition is bone, the site of B-cell development. In addition, our in vitro data suggest that developing B lymphocytes are susceptible to tungsten-induced DNA damage and growth inhibition. To extend these results, we assessed whether tungsten exposure altered B-cell development and induced DNA damage in vivo. Wild-type mice were exposed to tungsten in their drinking water for up to 16 weeks. Tungsten concentration in bone was analyzed by inductively coupled plasma mass spectrometry and correlated with B-cell development and DNA damage within the bone marrow. Tungsten exposure resulted in a rapid deposition within the bone following 1 week, and tungsten continued to accumulate thereafter albeit at a decreased rate. Flow cytometric analyses revealed a transient increase in mature IgD(+) B cells in the first 8 weeks of treatment, in animals of the highest and intermediate exposure groups. Following 16 weeks of exposure, all tungsten groups had a significantly greater percentage of cells in the late pro-/large pre-B developmental stages. DNA damage was increased in both whole marrow and isolated B cells, most notably at the lowest tungsten concentration tested. These findings confirm an immunological effect of tungsten exposure and suggest that tungsten could act as a tumor promoter, providing leukemic "hits" in multiple forms to developing B lymphocytes within the bone marrow.

  7. Altering adsorbed proteins or cellular gene expression in bone-metastatic cancer cells affects PTHrP and Gli2 without altering cell growth

    Directory of Open Access Journals (Sweden)

    Jonathan M. Page

    2015-09-01

    Full Text Available The contents of this data in brief are related to the article titled “Matrix Rigidity Regulates the Transition of Tumor Cells to a Bone-Destructive Phenotype through Integrin β3 and TGF-β Receptor Type II”. In this DIB we will present our supplemental data investigating Integrin expression, attachment of cells to various adhesion molecules, and changes in gene expression in multiple cancer cell lines. Since the interactions of Integrins with adsorbed matrix proteins are thought to affect the ability of cancer cells to interact with their underlying substrates, we examined the expression of Integrin β1, β3, and β5 in response to matrix rigidity. We found that only Iβ3 increased with increasing substrate modulus. While it was shown that fibronectin greatly affects the expression of tumor-produced factors associated with bone destruction (parathyroid hormone-related protein, PTHrP, and Gli2, poly-l-lysine, vitronectin and type I collagen were also analyzed as potential matrix proteins. Each of the proteins was independently adsorbed on both rigid and compliant polyurethane films which were subsequently used to culture cancer cells. Poly-l-lysine, vitronectin and type I collagen all had negligible effects on PTHrP or Gli2 expression, but fibronectin was shown to have a dose dependent effect. Finally, altering the expression of Iβ3 demonstrated that it is required for tumor cells to respond to the rigidity of the matrix, but does not affect other cell growth or viability. Together these data support the data presented in our manuscript to show that the rigidity of bone drives Integrinβ3/TGF-β crosstalk, leading to increased expression of Gli2 and PTHrP.

  8. Comparison of platelet rich plasma and synthetic graft material for bone regeneration after third molar extraction

    Science.gov (United States)

    Nathani, Dipesh B.; Sequeira, Joyce; Rao, B. H. Sripathi

    2015-01-01

    Aims: To compare the efficacy of Platelet rich plasma and synthetic graft material for bone regeneration after bilateral third molar extraction. Material and Methods: This study was conducted in 10 patients visiting the outpatient department of Oral & Maxillofacial Surgery, Yenepoya Dental College & Hospital. Patients requiring extraction of bilateral mandibular third molars were taken for the study. Following extraction, PRP (Platelet Rich Plasma) was placed in one extraction socket and synthetic graft material in form granules [combination of Hydroxyapatite (HA) and Bioactive glass (BG)] in another extraction socket. The patients were assessed for postoperative pain and soft tissue healing. Radiological assessment of the extraction site was done at 8, 12 and 16 weeks interval to compare the change in bone density in both the sockets. Results: Pain was less on PRP site when compared to HA site. Soft tissue evaluation done using gingival healing index given by Landry et al showed better healing on PRP site when compared to HA site. The evaluation of bone density by radiological assessment showed the grey level values calculated at 4 months at the PRP site were comparatively higher than HA site. Conclusion: The study showed that the platelet rich plasma is a better graft material than synthetic graft material in terms of soft tissue and bone healing. However a more elaborate study with a larger number of clinical cases is very much essential to be more conclusive regarding the efficacy of both the materials. PMID:26981473

  9. A new Fe–Mn–Si alloplastic biomaterial as bone grafting material: In vivo study

    Energy Technology Data Exchange (ETDEWEB)

    Fântânariu, Mircea, E-mail: mfantanariu@uaiasi.ro [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, no. 8, 700489, Iasi (Romania); Trincă, Lucia Carmen, E-mail: lctrinca@uaiasi.ro [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Horticulture, Str. Aleea M. Sadoveanu, no. 3, 700490, Iasi (Romania); Solcan, Carmen, E-mail: csolcan@yahoo.com [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, no. 8, 700489, Iasi (Romania); Trofin, Alina, E-mail: aetrofin@yahoo.com [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Horticulture, Str. Aleea M. Sadoveanu, no. 3, 700490, Iasi (Romania); Strungaru, Ştefan, E-mail: strungaru_stefan@yahoo.com [“Alexandru Ioan Cuza” University, Faculty of Biology, Bulevardul Carol I, Nr.11, 700506, Iasi (Romania); Şindilar, Eusebiu Viorel, E-mail: esindilar@uaiasi.ro [“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Str. Aleea M. Sadoveanu, no. 8, 700489, Iasi (Romania); Plăvan, Gabriel, E-mail: gabriel.plavan@uaic.ro [“Alexandru Ioan Cuza” University, Faculty of Biology, Bulevardul Carol I, Nr.11, 700506, Iasi (Romania); and others

    2015-10-15

    Highlights: • A Fe–Mn–Si alloy was obtained as alloplastic graft material for bone implants. • Fe–Mn–Si alloy degradation rate was preliminary evaluate with SEM and EDAX techniques. • Biochemical, histological, RX and CT investigations were done in rats with subcutaneous and tibiae implants. • Fe–Mn–Si alloy assured an ideal compromise between degradation and mechanical integrity during bone regeneration. - Abstract: Designing substrates having suitable mechanical properties and targeted degradation behavior is the key's development of bio-materials for medical application. In orthopedics, graft material may be used to fill bony defects or to promote bone formation in osseous defects created by trauma or surgical intervention. Incorporation of Si may increase the bioactivity of implant locally, both by enhancing interactions at the graft–host interface and by having a potential endocrine like effect on osteoblasts. A Fe–Mn–Si alloy was obtained as alloplastic graft materials for bone implants that need long recovery time period. The surface morphology of the resulted specimens was investigated using scanning electrons microscopy (VegaTescan LMH II, SE detector, 30 kV), X-ray diffractions (X’Pert equipment) or X-ray dispersive energy analyze (Bruker EDS equipment). This study objective was to evaluate in vivo the mechanisms of degradation and the effects of its implantation over the main metabolic organs. Biochemical, histological, plain X radiography and computed tomography investigations showed good compatibility of the subcutaneous implants in the rat organism. The implantation of the Fe–Mn–Si alloy, in critical size bone (tibiae) defect rat model, did not induced adverse biological reactions and provided temporary mechanical support to the affected bone area. The biodegradation products were hydroxides layers which adhered to the substrate surface. Fe–Mn–Si alloy assured the mechanical integrity in rat tibiae defects

  10. Pharmacogenetic risk factors for altered bone mineral density and body composition in pediatric acute lymphoblastic leukemia

    NARCIS (Netherlands)

    M.L. te Winkel (Mariël Lizet); R.D. van Beek (Robert Diederik); S.M.P.F. de Muinck Keizer-Schrama (Sabine); A.G. Uitterlinden (André); W.C.J. Hop (Wim); R. Pieters (Rob); M.M. van den Heuvel-Eibrink (Marry)

    2010-01-01

    textabstractBackground This study investigates pharmacogenetic risk factors for bone mineral (apparent) density (BM(A)D) and body composition in pediatric acute lymphoblastic leukemia Design and Methods We determined the influence of SNPs in 4 genes (vitamin-D receptor (VDR: BsmI/ApaI/TaqI and Cdx-2

  11. Impaired bone healing in multitrauma patients is associated with altered leukocyte kinetics after major trauma

    NARCIS (Netherlands)

    Bastian, Okan W; Kuijer, Anne; Koenderman, Leo; Stellato, Rebecca K; van Solinge, WW; Leenen, Luke PH; Blokhuis, Taco J

    2016-01-01

    Animal studies have shown that the systemic inflammatory response to major injury impairs bone regeneration. It remains unclear whether the systemic immune response contributes to impairment of fracture healing in multitrauma patients. It is well known that systemic inflammatory changes after major

  12. Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis

    DEFF Research Database (Denmark)

    Jafari Kermani, Abbas; Qanie, Diyako; Andersen, Thomas L

    2017-01-01

    Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells...

  13. Repairing rabbit radial defects by combining bone marrow stroma stem cells with bone scaffold material comprising a core-cladding structure.

    Science.gov (United States)

    Wu, H; Liu, G H; Wu, Q; Yu, B

    2015-10-05

    We prepared a bone scaffold material comprising a PLGA/β-TCP core and a Type I collagen cladding, and recombined it with bone marrow stroma stem cells (BMSCs) to evaluate its potential for use in bone tissue engineering by in vivo and in vitro experiments. PLGA/β-TCP without a cladding was used for comparison. The adherence rate of the BMSCs to the scaffold was determined by cell counting. Cell proliferation rate was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. The osteogenic capability was evaluated by alkaline phosphatase activity. The scaffold materials were recombined with the BMSCs and implanted into a large segmental rabbit radial defect model to evaluate defect repair. Osteogenesis was assessed in the scaffold materials by histological and double immunofluorescence labeling, etc. The adherence number, proliferation number, and alkaline phosphatase expression of the cells on the bone scaffold material with core-cladding structure were significantly higher than the corresponding values in the PLGA/β-TCP composite scaffold material (P cladding structure completely degraded at the bone defect site and bone formation was completed. The rabbit large sentimental radial defect was successfully repaired. The degradation and osteogenesis rates matched well. The bone scaffold with core-cladding structure exhibited better osteogenic activity and capacity to repair a large segmental bone defect compared to the PLGA/β-TCP composite scaffold. The bone scaffold with core-cladding structure has excellent physical properties and biocompatibility. It is an ideal scaffold material for bone tissue engineering.

  14. Biomechanical properties of an advanced new carbon/flax/epoxy composite material for bone plate applications.

    Science.gov (United States)

    Bagheri, Zahra S; El Sawi, Ihab; Schemitsch, Emil H; Zdero, Rad; Bougherara, Habiba

    2013-04-01

    This work is part of an ongoing program to develop a new carbon fiber/flax/epoxy (CF/flax/epoxy) hybrid composite material for use as an orthopaedic long bone fracture plate, instead of a metal plate. The purpose of this study was to evaluate the mechanical properties of this new novel composite material. The composite material had a "sandwich structure", in which two thin sheets of CF/epoxy were attached to each outer surface of the flax/epoxy core, which resulted in a unique structure compared to other composite plates for bone plate applications. Mechanical properties were determined using tension, three-point bending, and Rockwell hardness tests. Also, scanning electron microscopy (SEM) was used to characterize the failure mechanism of specimens in tension and three-point bending tests. The results of mechanical tests revealed a considerably high ultimate strength in both tension (399.8MPa) and flexural loading (510.6MPa), with a higher elastic modulus in bending tests (57.4GPa) compared to tension tests (41.7GPa). The composite material experienced brittle catastrophic failure in both tension and bending tests. The SEM images, consistent with brittle failure, showed mostly fiber breakage and fiber pull-out at the fractured surfaces with perfect bonding at carbon fibers and flax plies. Compared to clinically-used orthopaedic metal plates, current CF/flax/epoxy results were closer to human cortical bone, making the material a potential candidate for use in long bone fracture fixation.

  15. Osteogenic cells on bio-inspired materials for bone tissue engineering.

    Science.gov (United States)

    Vagaská, B; Bacáková, L; Filová, E; Balík, K

    2010-01-01

    This article reviews the development of artificial bone substitutes from their older single-phase forms to novel multi-phase composites, mimicking the composition and architecture of natural bone tissue. The new generation of bone implants should be bioactive, i.e. they should induce the desired cellular responses, leading to integration of the material into the natural tissue and stimulating self-healing processes. Therefore, the first part of the review explains the common principles of the cell-material interaction and summarizes the strategies how to improve the biocompatibility and bioactivity of the materials by modifying the physico-chemical properties of the material surface, such as surface chemistry, wettability, electrical charge, rigidity, microroughness and especially nanoroughness. The latter has been shown to stimulate preferentially the growth of osteoblasts in comparison with other competitive cell types, such as fibroblasts, which could prevent fibrous tissue formation upon implantation. The second more specialized part of the review deals with materials suitable for bone contact and substitution, particularly novel polymer-based composites reinforced with fibres or inorganic particles and containing bioactive components, such as crystals of hydroxyapatite or other calcium phosphates, synthetic ligands for cell adhesion receptors or growth factors. Moreover, if they are degradable, they can be gradually replaced with a regenerating tissue.

  16. Elastic moduli of untreated, demineralized and deproteinized cortical bone: validation of a theoretical model of bone as an interpenetrating composite material.

    Science.gov (United States)

    Hamed, E; Novitskaya, E; Li, J; Chen, P-Y; Jasiuk, I; McKittrick, J

    2012-03-01

    A theoretical experimentally based multi-scale model of the elastic response of cortical bone is presented. It portrays the hierarchical structure of bone as a composite with interpenetrating biopolymers (collagen and non-collagenous proteins) and minerals (hydroxyapatite), together with void spaces (porosity). The model involves a bottom-up approach and employs micromechanics and classical lamination theories of composite materials. Experiments on cortical bone samples from bovine femur include completely demineralized and deproteinized bones as well as untreated bone samples. Porosity and microstructure are characterized using optical and scanning electron microscopy, and micro-computed tomography. Compression testing is used to measure longitudinal and transverse elastic moduli of all three bone types. The characterization of structure and properties of these three bone states provides a deeper understanding of the contributions of the individual components of bone to its elastic response and allows fine tuning of modeling assumptions. Very good agreement is found between theoretical modeling and compression testing results, confirming the validity of the interpretation of bone as an interpenetrating composite material.

  17. Pneumatization of the Temporal Bones in a Greenlandic Inuit Anthropological Material

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N

    1991-01-01

    The degree of pneumatization of the temporal bones correlates with exposure during childhood and adolescence to infectious middle ear diseases (IMED), both acute and chronic. The pneumatized area as seen on cranial X-rays can be measured. This was applied to an anthropological material in order...

  18. Influence of Material Properties on Rate of Resorption of Two Bone Graft Materials after Sinus Lift Using Radiographic Assessment

    Directory of Open Access Journals (Sweden)

    Fawzi Riachi

    2012-01-01

    Full Text Available Purpose. The aim of this study was to investigate the influence of chemical and physical properties of two graft materials on the rate of resorption. Materials and Methods. Direct sinus graft procedure was performed on 22 patients intended for implant placement. Two types of graft materials were used (Bio-Oss and Cerabone and after 8 months healing time the implants were inserted. Radiographic assessment was performed over the period of four years. Particle size, rate of calcium release, and size and type of crystal structure of each graft were evaluated. Results. The average particle size of Bio-Oss (1 mm was much smaller compared to Cerabone (2.7 mm. The amount of calcium release due to dissolution of material in water was much higher for Bio-oss compared to Cerabone. X-ray image analysis revealed that Bio-Oss demonstrated significantly higher volumetric loss (33.4 ± 3.1% of initial graft size compared to Cerabone (23.4 ± 3.6%. The greatest amount of vertical loss of graft material volume was observed after one year of surgery. Conclusion. The chemical and physical properties of bone graft material significantly influence resorption rate of bone graft materials used for sinus augmentation.

  19. A biocompatible hybrid material with simultaneous calcium and strontium release capability for bone tissue repair

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, J. Carlos [CICECO — Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Wacha, András [Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok körútja 2, Budapest 1117 (Hungary); Gomes, Pedro S. [Laboratory for Bone Metabolism and Regeneration, Faculdade de Medicina Dentária, Universidade do Porto (Portugal); Alves, Luís C. [C2TN, Instituto Superior Técnico, Universidade de Lisboa, E.N.10, 2695-066 Bobadela LRS (Portugal); Fernandes, M. Helena Vaz [CICECO — Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Salvado, Isabel M. Miranda, E-mail: isabelmsalvado@ua.pt [CICECO — Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Fernandes, M. Helena R. [Laboratory for Bone Metabolism and Regeneration, Faculdade de Medicina Dentária, Universidade do Porto (Portugal)

    2016-05-01

    The increasing interest in the effect of strontium in bone tissue repair has promoted the development of bioactive materials with strontium release capability. According to literature, hybrid materials based on the system PDMS–SiO{sub 2} have been considered a plausible alternative as they present a mechanical behavior similar to the one of the human bone. The main purpose of this study was to obtain a biocompatible hybrid material with simultaneous calcium and strontium release capability. A hybrid material, in the system PDMS–SiO{sub 2}–CaO–SrO, was prepared with the incorporation of 0.05 mol of titanium per mol of SiO{sub 2}. Calcium and strontium were added using the respective acetates as sources, following a sol–gel technique previously developed by the present authors. The obtained samples were characterized by FT-IR, solid-state NMR, and SAXS, and surface roughness was analyzed by 3D optical profilometry. In vitro studies were performed by immersion of the samples in Kokubo's SBF for different periods of time, in order to determine the bioactive potential of these hybrids. Surfaces of the immersed samples were observed by SEM, EDS and PIXE, showing the formation of calcium phosphate precipitates. Supernatants were analyzed by ICP, revealing the capability of the material to simultaneously fix phosphorus ions and to release calcium and strontium, in a concentration range within the values reported as suitable for the induction of the bone tissue repair. The material demonstrated to be cytocompatible when tested with MG63 osteoblastic cells, exhibiting an inductive effect on cell proliferation and alkaline phosphatase activity. - Highlights: • A hybrid PDMS–SiO{sub 2}–CaO–SrO material was prepared with the incorporation of Ti. • Sr was released in concentrations suitable for the induction of bone tissue repair. • The material demonstrated to be cytocompatible when tested with osteoblastic cells.

  20. Materials and prognostic factors of bone regeneration in periapical surgery: A systematic review

    OpenAIRE

    Sánchez Torres, Alba; Sánchez Garcés, María Angeles; Gay Escoda, Cosme

    2014-01-01

    Objectives: Analyse the effectiveness of different materials and techniques used in guided tissue regeneration (GTR) applied in periapical surgery, comparing the success rate obtained in 4-wall defects and in through-and-through bone lesions as well as to establish prognostic factors. Material and Methods: A Cochrane, PubMed-MEDLINE and Scopus database search (October 2012 to March 2013) was conducted with the search terms “periapical surgery”, “surgical endodontic treatment”, “guided tissue ...

  1. Fresh-frozen bone: case series of a new grafting material for sinus lift and immediate implants.

    LENUS (Irish Health Repository)

    Viscioni, A

    2010-08-01

    Although autologous bone is considered to be the gold standard grafting material, it needs to be harvested from patients, a process that can be off-putting and can lead to donor site morbidity. For this reason, homologous fresh-frozen bone (FFB) was used in the current study as an alternative graft material.

  2. Bone Regeneration after Treatment with Covering Materials Composed of Flax Fibers and Biodegradable Plastics: A Histological Study in Rats

    Science.gov (United States)

    Gedrange, Tomasz

    2016-01-01

    The aim of this study was to examine the osteogenic potential of new flax covering materials. Bone defects were created on the skull of forty rats. Materials of pure PLA and PCL and their composites with flax fibers, genetically modified producing PHB (PLA-transgen, PCL-transgen) and unmodified (PLA-wt, PCL-wt), were inserted. The skulls were harvested after four weeks and subjected to histological examination. The percentage of bone regeneration by using PLA was less pronounced than after usage of pure PCL in comparison with controls. After treatment with PCL-transgen, a large amount of new formed bone could be found. In contrast, PCL-wt decreased significantly the bone regeneration, compared to the other tested groups. The bone covers made of pure PLA had substantially less influence on bone regeneration and the bone healing proceeded with a lot of connective tissue, whereas PLA-transgen and PLA-wt showed nearly comparable amount of new formed bone. Regarding the histological data, the hypothesis could be proposed that PCL and its composites have contributed to a higher quantity of the regenerated bone, compared to PLA. The histological studies showed comparable bone regeneration processes after treatment with tested covering materials, as well as in the untreated bone lesions. PMID:27597965

  3. Bone Regeneration after Treatment with Covering Materials Composed of Flax Fibers and Biodegradable Plastics: A Histological Study in Rats.

    Science.gov (United States)

    Gredes, Tomasz; Kunath, Franziska; Gedrange, Tomasz; Kunert-Keil, Christiane

    2016-01-01

    The aim of this study was to examine the osteogenic potential of new flax covering materials. Bone defects were created on the skull of forty rats. Materials of pure PLA and PCL and their composites with flax fibers, genetically modified producing PHB (PLA-transgen, PCL-transgen) and unmodified (PLA-wt, PCL-wt), were inserted. The skulls were harvested after four weeks and subjected to histological examination. The percentage of bone regeneration by using PLA was less pronounced than after usage of pure PCL in comparison with controls. After treatment with PCL-transgen, a large amount of new formed bone could be found. In contrast, PCL-wt decreased significantly the bone regeneration, compared to the other tested groups. The bone covers made of pure PLA had substantially less influence on bone regeneration and the bone healing proceeded with a lot of connective tissue, whereas PLA-transgen and PLA-wt showed nearly comparable amount of new formed bone. Regarding the histological data, the hypothesis could be proposed that PCL and its composites have contributed to a higher quantity of the regenerated bone, compared to PLA. The histological studies showed comparable bone regeneration processes after treatment with tested covering materials, as well as in the untreated bone lesions.

  4. Low-dose developmental exposure to bisphenol A alters the femoral bone geometry in wistar rats

    DEFF Research Database (Denmark)

    Lejonklou, M. H.; Christiansen, Sofie; Orberg, J.

    2016-01-01

    Background: Bisphenol A (BPA) is a chemical produced in large volumes for use in manufacturing of consumer products and industrial applications, and an endocrine disruptor known to affect several hormonal systems. Bone produces hormones and is additionally a sensitive hormone target tissue......, and is thus potentially sensitive to low doses of endocrine disruptors such as BPA, especially during development.Methods: 110 pregnant Wistar rats were gavaged with 0; 25 mu g; 250 mu g; 5000 mu g or 50,000 mu g BPA/kg bodyweight (bw)/day from gestational day 7 until weaning at postnatal day 22. The three...

  5. Alterations of the Bone Marrow Microenvironment Contribute to Prostate Cancer Skeletal Metastasis

    Science.gov (United States)

    2012-05-01

    584–593. doi:10.1038/ nrc867 14. Roodman GD (2004) Mechanisms of bone metastasis. New Engl J Med 350(16):1655–1664. doi:10.1056/NEJMra030831 15...90. doi:10.1182/blood-2006-05-021352 39. Shiozawa Y, Havens AM, Jung Y, Ziegler AM, Pedersen EA, Wang J, Lu G, Roodman GD, Loberg RD, Pienta KJ...6 Fabiana N. Soki1, David Sadler1, Sudha Sud2, Sandra Tisdelle5, Stephanie D. Daignault4, Jeffrey A. Nemeth6, 7 Linda A. Snyder6, Thomas J. Wronski5

  6. Biomineralization of Engineered Spider Silk Protein-Based Composite Materials for Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    John G. Hardy

    2016-07-01

    Full Text Available Materials based on biodegradable polyesters, such as poly(butylene terephthalate (PBT or poly(butylene terephthalate-co-poly(alkylene glycol terephthalate (PBTAT, have potential application as pro-regenerative scaffolds for bone tissue engineering. Herein, the preparation of films composed of PBT or PBTAT and an engineered spider silk protein, (eADF4(C16, that displays multiple carboxylic acid moieties capable of binding calcium ions and facilitating their biomineralization with calcium carbonate or calcium phosphate is reported. Human mesenchymal stem cells cultured on films mineralized with calcium phosphate show enhanced levels of alkaline phosphatase activity suggesting that such composites have potential use for bone tissue engineering.

  7. A novel composite material specifically developed for ultrasound bone phantoms: cortical, trabecular and skull.

    Science.gov (United States)

    Wydra, A; Maev, R Gr

    2013-11-21

    In the various stages of developing diagnostic and therapeutic equipment, the use of phantoms can play a very important role in improving the process, help in implementation, testing and calibrations. Phantoms are especially useful in developing new applications and training new doctors in medical schools. However, devices that use different physical factors, such as MRI, Ultrasound, CT Scan, etc will require the phantom to be made of different physical properties. In this paper we introduce the properties of recently designed new materials for developing phantoms for ultrasonic human body investigation, which in today's market make up more than 30% in the world of phantoms. We developed a novel composite material which allows fabrication of various kinds of ultrasound bone phantoms to mimic most of the acoustical properties of human bones. In contrast to the ex vivo tissues, the proposed material can maintain the physical and acoustical properties unchanged for long periods of time; moreover, these properties can be custom designed and created to suit specific needs. As a result, we introduce three examples of ultrasound phantoms that we manufactured in our laboratory: cortical, trabecular and skull bone phantoms. The paper also presents the results of a comparison study between the acoustical and physical properties of actual human bones (reported in the referenced literatures) and the phantoms manufactured by us.

  8. Investigating the weight ratio variation of alginate-hydroxyapatite composites for vertebroplasty method bone filler material

    Science.gov (United States)

    Lestari, Gusti Ruri; Yuwono, Akhmad Herman; Sofyan, Nofrijon; Ramahdita, Ghiska

    2017-02-01

    One of the newly developed methods for curing spinal fracture due to osteoporosis is vertebroplasty. The method is basically based on injection of special material directly to the fractured spine in order to commence the formation of new bone. Therefore, appropriate injectable materials are very important to the curing success. In this study, injectable alginate-hydroxyapatite (HA) composites were fabricated varying the weight percentage of alginate upon synthesis procedure. The result of injection capability and compressive tests as well as Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM) suggested that bone filler composite containing 60 wt% alginate is the optimum composition obtaining a compressive modulus up to 0.15 MPa, injection capability of more than 85% and morphology with uniform porous and fibrous structure. This injectable composite fabrication process can be used for the development of injectable materials system for vertebroplasty method.

  9. Persistent DNA damage-induced premature senescence alters the functional features of human bone marrow mesenchymal stem cells.

    Science.gov (United States)

    Minieri, Valentina; Saviozzi, Silvia; Gambarotta, Giovanna; Lo Iacono, Marco; Accomasso, Lisa; Cibrario Rocchietti, Elisa; Gallina, Clara; Turinetto, Valentina; Giachino, Claudia

    2015-04-01

    Human mesenchymal stem cells (hMSCs) are adult multipotent stem cells located in various tissues, including the bone marrow. In contrast to terminally differentiated somatic cells, adult stem cells must persist and function throughout life to ensure tissue homeostasis and repair. For this reason, they must be equipped with DNA damage responses able to maintain genomic integrity while ensuring their lifelong persistence. Evaluation of hMSC response to genotoxic insults is of great interest considering both their therapeutic potential and their physiological functions. This study aimed to investigate the response of human bone marrow MSCs to the genotoxic agent Actinomycin D (ActD), a well-known anti-tumour drug. We report that hMSCs react by undergoing premature senescence driven by a persistent DNA damage response activation, as hallmarked by inhibition of DNA synthesis, p21 and p16 protein expression, marked Senescent Associated β-galactosidase activity and enlarged γH2AX foci co-localizing with 53BP1 protein. Senescent hMSCs overexpress several senescence-associated secretory phenotype (SASP) genes and promote motility of lung tumour and osteosarcoma cell lines in vitro. Our findings disclose a multifaceted consequence of ActD treatment on hMSCs that on the one hand helps to preserve this stem cell pool and prevents damaged cells from undergoing neoplastic transformation, and on the other hand alters their functional effects on the surrounding tissue microenvironment in a way that might worsen their tumour-promoting behaviour.

  10. Biocompatible glass-ceramic materials for bone substitution.

    Science.gov (United States)

    Vitale-Brovarone, Chiara; Verné, Enrica; Robiglio, Lorenza; Martinasso, Germana; Canuto, Rosa A; Muzio, Giuliana

    2008-01-01

    A new bioactive glass composition (CEL2) in the SiO(2)-P(2)O(5)-CaO-MgO-K(2)O-Na(2)O system was tailored to control pH variations due to ion leaching phenomena when the glass is in contact with physiological fluids. CEL2 was prepared by a traditional melting-quenching process obtaining slices that were heat-treated to obtain a glass-ceramic material (CEL2GC) that was characterized thorough SEM analysis. Pre-treatment of CEL2GC with SBF was found to enhance its biocompatibility, as assessed by in vitro tests. CEL2 powder was then used to synthesize macroporous glass-ceramic scaffolds. To this end, CEL2 powders were mixed with polyethylene particles within the 300-600 microm size-range and then pressed to obtain crack-free compacted powders (green). This was heat-treated to remove the organic phase and to sinter the inorganic phase, leaving a porous structure. The biomaterial thus obtained was characterized by X-ray diffraction, SEM equipped with EDS, density measurement, image analysis, mechanical testing and in vitro evaluation, and found to be a glass-ceramic macroporous scaffold with uniformly distributed and highly interconnected porosity. The extent and size-range of the porosity can be tailored by varying the amount and size of the polyethylene particles.

  11. Tooth Movement out of the Bony Wall Using Augmented Corticotomy with Nonautogenous Graft Materials for Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Kye-Bok Lee

    2014-01-01

    Full Text Available This prospective randomized split-mouth study was performed to compare the effects of augmented corticotomy with those of different nonautogenous bone graft materials combined with orthodontic tooth movement in dogs. Decortication was performed on the buccal bone surface of 6 male beagle dogs that were randomly assigned to receive grafts of deproteinized bovine bone mineral, irradiated cortical bone, or synthetic bone. Immediate orthodontic force was applied to the second and third premolars for buccal tipping for 6 weeks. The pocket depth and width of keratinized tissue (WKT were measured. Histologic and histomorphometric analyses were performed. The probing depth, WKT, and ratio of the area of new bone to that of total bone on the buccal side were not significantly different between groups. All groups had considerable new bone formation on the pressure side. New bone formation on the buccal side and buccal plate formation in the coronal direction along the root surfaces were induced by the bone-derived and PDL-derived mesenchymal matrix, respectively. The angular change between groups was significantly different (P < 0.001. Augmented corticotomy using nonautogenous graft materials facilitated tooth movement without fenestrations and accelerated new bone formation on the pressure side.

  12. Prediction of Local Ultimate Strain and Toughness of Trabecular Bone Tissue by Raman Material Composition Analysis

    Directory of Open Access Journals (Sweden)

    Roberto Carretta

    2015-01-01

    Full Text Available Clinical studies indicate that bone mineral density correlates with fracture risk at the population level but does not correlate with individual fracture risk well. Current research aims to better understand the failure mechanism of bone and to identify key determinants of bone quality, thus improving fracture risk prediction. To get a better understanding of bone strength, it is important to analyze tissue-level properties not influenced by macro- or microarchitectural factors. The aim of this pilot study was to identify whether and to what extent material properties are correlated with mechanical properties at the tissue level. The influence of macro- or microarchitectural factors was excluded by testing individual trabeculae. Previously reported data of mechanical parameters measured in single trabeculae under tension and bending and its compositional properties measured by Raman spectroscopy was evaluated. Linear and multivariate regressions show that bone matrix quality but not quantity was significantly and independently correlated with the tissue-level ultimate strain and postyield work (r=0.65–0.94. Principal component analysis extracted three independent components explaining 86% of the total variance, representing elastic, yield, and ultimate components according to the included mechanical parameters. Some matrix parameters were both included in the ultimate component, indicating that the variation in ultimate strain and postyield work could be largely explained by Raman-derived compositional parameters.

  13. 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.

  14. An Injectable Hydrogel as Bone Graft Material with Added Antimicrobial Properties

    Science.gov (United States)

    Tommasi, Giacomo; Perni, Stefano

    2016-01-01

    Currently, the technique which provides the best chances for a successful bone graft, is the use of bone tissue from the same patient receiving it (autograft); the main limitations are the limited availability and the risks involved in removing living bone tissue, for example, explant site pain and morbidity. Allografts and xenografts may overcome these limitations; however, they increase the risk of rejection. For all these reasons the development of an artificial bone graft material is particularly important and hydrogels are a promising alternative for bone regeneration. Gels were prepared using 1,4-butanediol diacrylate as crosslinker and alpha tricalciumphosphate; ZnCl2 and SrCl2 were added to the aqueous phase. MTT results demonstrated that the addition of strontium had a beneficial effect on the osteoblast cells density on hydrogels, and zinc instead did not increase osteoblast proliferation. The amount of calcium produced by the osteoblast cells quantified through the Alizarin Red protocol revealed that both strontium and zinc positively influenced the formation of calcium; furthermore, their effect was synergistic. Rheology properties were used to mechanically characterize the hydrogels and especially the influence of crosslinker's concentration on them, showing the hydrogels presented had extremely good mechanical properties. Furthermore, the antimicrobial activity of strontium and zinc in the hydrogels against methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis was determined. PMID:27174392

  15. Validation of an efficient method of assigning material properties in finite element analysis of pelvic bone.

    Science.gov (United States)

    Shim, Vickie B; Battley, Mark; Anderson, Iain A; Munro, Jacob T

    2015-01-01

    Bone in the pelvis is a composite material with a complex anatomical structure that is difficult to model computationally. Rather than assigning material properties to increasingly smaller elements to capture detail in three-dimensional finite element (FE) models, properties can be assigned to Gauss points within larger elements. As part of a validation process, we compared experimental and analytical results from a composite beam under four-point load to FE models with material properties assigned to refined elements and Gauss points within larger elements. Both FE models accurately predicted deformation and the analytical predictions of internal shear stress.

  16. Properties of the "Orgamax" osteoplastic material made of a demineralized allograft bone

    Science.gov (United States)

    Podorognaya, V. T.; Kirilova, I. A.; Sharkeev, Yu. P.; Uvarkin, P. V.; Zhelezny, P. A.; Zheleznaya, A. P.; Akimova, S. E.; Novoselov, V. P.; Tupikova, L. N.

    2016-08-01

    We investigated properties of the "Orgamax" osteoplastic material, which was produced from a demineralized bone, in the treatment of extensive caries, in particular chronic pulpitis of the permanent teeth with unformed roots in children. The "Orgamax" osteoplastic material consists of demineralized bone chips, a collagen additive, and antibiotics. The surface morphology of the "Orgamax" osteoplastic material is macroporous, with the maximum pore size of 250 µm, whereas the surface morphology of the major component of "Orgamax", demineralized bone chips, is microporous, with a pore size of 10-20 µm. Material "Orgamax" is used in the treatment of complicated caries, particularly chronic pulpitis of permanent teeth with unformed roots in children. "Orgamax" filling a formed cavity exhibits antimicrobial properties, eliminates inflammation in the dental pulp, and, due to its osteoconductive and osteoinductive properties, undergoes gradual resorption, stimulates regeneration, and provides replacement of the defect with newly formed tissue. The dental pulp viability is completely restored, which ensures the complete formation of tooth roots with root apex closure in the long-term period.

  17. TU-A-12A-08: Computing Longitudinal Material Changes in Bone Metastases Using Dual Energy Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schmidtlein, CR; Hwang, S; Veeraraghavan, H; Fehr, D; Humm, J; Deasy, J [Memorial Sloan Kettering Cancer Center, New York, NY (United States)

    2014-06-15

    Purpose: This study demonstrates a methodology for tracking changes in metastatic bone disease using trajectories in material basis space in serial dual energy computed tomography (DECT) studies. Methods: This study includes patients with bone metastases from breast cancer that had clinical surveillance CT scans using a General Electric CT750HD in dual energy mode. A radiologist defined regions-of-interested (ROI) for bone metastasis, normal bone, and marrow across the serial DECT scans. Our approach employs a Radon transform to forward-projection the basis images, namely, water and iodine, into sinogram space. This data is then repartitioned into fat/bone and effective density/Z image pairs using assumed energy spectrums for the x-ray energies. This approach both helps remove negative material densities and avoids adding spectrum-hardening artifacts. These new basis data sets were then reconstructed via filtered back-projection to create new material basis pair images. The trajectories of these pairs were then plotted in the new basis space providing a means to both visualize and quantitatively measure changes in the material properties of the tumors. Results: ROI containing radiologist defined metastatic bone disease showed well-defined trajectories in both fat/bone and effective density/Z space. ROI that contained radiologist defined normal bone and marrow did not exhibit any discernible trajectories and were stable from scan to scan. Conclusions: The preliminary results show that changes in material composition and effective density/Z image pairs were seen primarily in metastasis and not in normal tissue. This study indicates that by using routine clinical DECT it may be possible to monitor therapy response of bone metastases because healing or worsening bone metastases change material composition of bone. Additional studies are needed to further validate these results and to test for their correlation with outcome.

  18. Femtosecond Laser Irradiation of Plasmonic Nanoparticles in Polymer Matrix: Implications for Photothermal and Photochemical Material Alteration

    Directory of Open Access Journals (Sweden)

    Anton A. Smirnov

    2014-11-01

    Full Text Available We analyze the opportunities provided by the plasmonic nanoparticles inserted into the bulk of a transparent medium to modify the material by laser light irradiation. This study is provoked by the advent of photo-induced nano-composites consisting of a typical polymer matrix and metal nanoparticles located in the light-irradiated domains of the initially homogeneous material. The subsequent irradiation of these domains by femtosecond laser pulses promotes a further alteration of the material properties. We separately consider two different mechanisms of material alteration. First, we analyze a photochemical reaction initiated by the two-photon absorption of light near the plasmonic nanoparticle within the matrix. We show that the spatial distribution of the products of such a reaction changes the symmetry of the material, resulting in the appearance of anisotropy in the initially isotropic material or even in the loss of the center of symmetry. Second, we analyze the efficiency of a thermally-activated chemical reaction at the surface of a plasmonic particle and the distribution of the product of such a reaction just near the metal nanoparticle irradiated by an ultrashort laser pulse.

  19. Alterations of mass density and 3D osteocyte lacunar properties in bisphosphonate-related osteonecrotic human jaw bone, a synchrotron µCT study.

    Directory of Open Access Journals (Sweden)

    Bernhard Hesse

    Full Text Available Osteonecrosis of the jaw, in association with bisphosphonates (BRONJ used for treating osteoporosis or cancer, is a severe and most often irreversible side effect whose underlying pathophysiological mechanisms remain largely unknown. Osteocytes are involved in bone remodeling and mineralization where they orchestrate the delicate equilibrium between osteoclast and osteoblast activity and through the active process called osteocytic osteolysis. Here, we hypothesized that (i changes of the mineralized tissue matrix play a substantial role in the pathogenesis of BRONJ, and (ii the osteocyte lacunar morphology is altered in BRONJ. Synchrotron µCT with phase contrast is an appropriate tool for assessing both the 3D morphology of the osteocyte lacunae and the bone matrix mass density. Here, we used this technique to investigate the mass density distribution and 3D osteocyte lacunar properties at the sub-micrometer scale in human bone samples from the jaw, femur and tibia. First, we compared healthy human jaw bone to human tibia and femur in order to assess the specific differences and address potential explanations of why the jaw bone is exclusively targeted by the necrosis as a side effect of BP treatment. Second, we investigated the differences between BRONJ and control jaw bone samples to detect potential differences which could aid an improved understanding of the course of BRONJ. We found that the apparent mass density of jaw bone was significantly smaller compared to that of tibia, consistent with a higher bone turnover in the jaw bone. The variance of the lacunar volume distribution was significantly different depending on the anatomical site. The comparison between BRONJ and control jaw specimens revealed no significant increase in mineralization after BP. We found a significant decrease in osteocyte-lacunar density in the BRONJ group compared to the control jaw. Interestingly, the osteocyte-lacunar volume distribution was not altered after

  20. Tensile material properties of human rib cortical bone under quasi-static and dynamic failure loading and influence of the bone microstucture on failure characteristics

    CERN Document Server

    Subit, Damien; Valazquez-Ameijide, Juan; Arregui-Dalmases, Carlos; Crandall, Jeff

    2011-01-01

    Finite element models of the thorax are under development to assist vehicle safety researchers with the design of countermeasures such as advanced restrain systems. Computational models have become more refined with increasing geometrical complexity as element size decreases. These finite element models can now capture small geometrical features with an attempt to predict fracture. However, the bone material properties currently available, and in particular the rate sensitivity, have been mainly determined from compression tests or tests on long bones. There is a need for a new set of material properties for the human rib cortical bone. With this objective, a new clamping technique was developed to test small bone coupons under tensile loading. Ten coupons were harvested from the cortical shell of the sixth and seventh left ribs from three cadavers. The coupons were tested to fracture under quasi-static (target strain rate of 0.07 %/s) and dynamic loading (target strain rate of 170 %/s). Prior to testing, eac...

  1. Therapy with bone marrow cells reduces liver alterations in mice chronically infected by Schistosoma mansoni

    Institute of Scientific and Technical Information of China (English)

    Sheilla Andrade Oliveira; Bruno Solano Freitas Souza; Cada Adriana Guimar(a)es-Ferreira; Elton Sá Barreto; Siane Campos Souza; Luiz Antonio Rodrigues Freitas; Ricardo Ribeiro-dos-Santos; Milena Botelho Pereira Soares

    2008-01-01

    AIM: To investigate the potential of bone marrow mononuclear cells (BM-MCs) in the regeneration of hepatic lesions induced by Schistosoma mansoni (S.mansoni) chronic infection.METHODS: Female mice chronically infected with S.mansoni were treated with BM-MCs obtained from male green fluorescent protein (GFP) transgenic mice by intravenous or intralobular injections. Control mice received injections of saline in similar conditions. Enzyme-linked immunosorbent assay (ELISA) assay for transforming growth factor-beta (TGF-β), polymerase chain reaction (PCR) for GFP DNA, immunofluorescence and morphometric studies were performed.RESULTS: Transplanted GFP+ cells migrated to granuloma areas and reduced the percentage of liver fibrosis. The presence of donor-derived cells was confirmed by Fluorescence in situ hybridization (FISH) analysis for detection of cells bearing Y chromosome and by PCR analysis for detection of GFP DNA. The levels of TGF-β, a cytokine associated with fibrosis deposition, in liver fragments of mice submitted to therapy were reduced. The number of oval cells in liver sections of S.rnansoni-infected mice increased 3-4 fold after transplantation. A partial recovery in albumin expression, which is decreased upon infection with S.mansoni, was found in livers of infected mice after cellular therapy.CONCLUSION: In conclusion, transplanted BMCs migrate to and reduce the damage of chronic fibrotic liver lesions caused by S.mansoni.

  2. Impaired bone healing in multitrauma patients is associated with altered leukocyte kinetics after major trauma

    Directory of Open Access Journals (Sweden)

    Bastian OW

    2016-05-01

    Full Text Available Okan W Bastian,1 Anne Kuijer,1 Leo Koenderman,2 Rebecca K Stellato,3 Wouter W van Solinge,4 Luke PH Leenen,1 Taco J Blokhuis1 1Department of Traumatology, 2Department of Respiratory Medicine, 3Department of Biostatistics and Research Support, Julius Center, 4Department of Clinical Chemistry and Hematology, University Medical Center Utrecht, Utrecht, the Netherlands Abstract: Animal studies have shown that the systemic inflammatory response to major injury impairs bone regeneration. It remains unclear whether the systemic immune response contributes to impairment of fracture healing in multitrauma patients. It is well known that systemic inflammatory changes after major trauma affect leukocyte kinetics. We therefore retrospectively compared the cellular composition of peripheral blood during the first 2 weeks after injury between multitrauma patients with normal (n=48 and impaired (n=32 fracture healing of the tibia. The peripheral blood-count curves of leukocytes, neutrophils, monocytes, and thrombocytes differed significantly between patients with normal and impaired fracture healing during the first 2 weeks after trauma (P-values were 0.0122, 0.0083, 0.0204, and <0.0001, respectively. Mean myeloid cell counts were above reference values during the second week after injury. Our data indicate that leukocyte kinetics differ significantly between patients with normal and impaired fracture healing during the first 2 weeks after major injury. This finding suggests that the systemic immune response to major trauma can disturb tissue regeneration. Keywords: SIRS, inflammation, neutrophils, myelopoiesis, regeneration

  3. Altering the Microenvironment to Promote Dormancy of Metastatic Breast Cancer Cell in a 3D Bone Culture System

    Science.gov (United States)

    2015-12-01

    1138-1148. Carlsten, H. 2005. Immune responses and bone loss: the estrogen connection. Immunological reviews . 208:194- 206. 28 Gehler, S., S.M...factors to be considered in cancer recurrence ( reviewed by [6]). Das Roy et al. found an increase in lung and bone marrow metastasis using an...activation of COX-2, plays an important role in normal bone physiology as well as in cancer and bone metastasis ( review [43]). In the normal bone, PGE2 is the

  4. Tooth movement out of the bony wall using augmented corticotomy with nonautogenous graft materials for bone regeneration.

    Science.gov (United States)

    Lee, Kye-Bok; Lee, Dong-Yeol; Ahn, Hyo-Won; Kim, Seong-Hun; Kim, Eun-Cheol; Roitman, Igor

    2014-01-01

    This prospective randomized split-mouth study was performed to compare the effects of augmented corticotomy with those of different nonautogenous bone graft materials combined with orthodontic tooth movement in dogs. Decortication was performed on the buccal bone surface of 6 male beagle dogs that were randomly assigned to receive grafts of deproteinized bovine bone mineral, irradiated cortical bone, or synthetic bone. Immediate orthodontic force was applied to the second and third premolars for buccal tipping for 6 weeks. The pocket depth and width of keratinized tissue (WKT) were measured. Histologic and histomorphometric analyses were performed. The probing depth, WKT, and ratio of the area of new bone to that of total bone on the buccal side were not significantly different between groups. All groups had considerable new bone formation on the pressure side. New bone formation on the buccal side and buccal plate formation in the coronal direction along the root surfaces were induced by the bone-derived and PDL-derived mesenchymal matrix, respectively. The angular change between groups was significantly different (P tooth movement without fenestrations and accelerated new bone formation on the pressure side.

  5. In Vitro Evaluation of Nanoscale Hydroxyapatite-Based Bone Reconstructive Materials with Antimicrobial Properties.

    Science.gov (United States)

    Ajduković, Zorica R; Mihajilov-Krstev, Tatjana M; Ignjatović, Nenad L; Stojanović, Zoran; Mladenović-Antić, Snezana B; Kocić, Branislava D; Najman, Stevo; Petrović, Nenad D; Uskoković, Dragan P

    2016-02-01

    In the field of oral implantology the loss of bone tissue prevents adequate patient care, and calls for the use of synthetic biomaterials with properties that resemble natural bone. Special attention is paid to the risk of infection after the implantation of these materials. Studies have suggested that some nanocontructs containing metal ions have antimicrobial properties. The aim of this study was to examine the antimicrobial and hemolytic activity of cobalt-substituted hydroxyapatite nanoparticles, compared to hydroxyapatite and hydroxyapatite/poly-lactide-co-glycolide. The antibacterial effects of these powders were tested against two pathogenic bacterial strains: Escherichia coi (ATCC 25922) and Staphylococcus aureus (ATCC 25923), using the disc diffusion method and the quantitative antimicrobial test in a liquid medium. The quantitative antimicrobial test showed that all of the tested biomaterials have some antibacterial properties. The effects of both tests were more prominent in case of S. aureus than in E coli. A higher percentage of cobalt in the crystal structure of cobalt-substituted hydroxyapatite nanoparticles led to an increased antimicrobial activity. All of the presented biomaterial samples were found to be non-hemolytic. Having in mind that the tested of cobalt-substituted hydroxyapatite (Ca/Co-HAp) material in given concentrations shows good hemocompatibility and antimicrobial effects, along with its previously studied biological properties, the conclusion can be reached that it is a potential candidate that could substitute calcium hydroxyapatite as the material of choice for use in bone tissue engineering and clinical practices in orthopedic, oral and maxillofacial surgery.

  6. Cell response of calcium phosphate based ceramics, a bone substitute material

    Directory of Open Access Journals (Sweden)

    Juliana Marchi

    2013-01-01

    Full Text Available The aim of this study was to characterize calcium phosphate ceramics with different Ca/P ratios and evaluate cell response of these materials for use as a bone substitute. Bioceramics consisting of mixtures of hydroxyapatite (HAp and β-tricalcium phosphate (β-TCP powders in different proportions were pressed and sintered. The physical and chemical properties of these bioceramics were then characterized. Characterization of the biological properties of these materials was based on analysis of cell response using cultured fibroblasts. The number of cells attached to the samples was counted from SEM images of samples exposed to cell culture solution for different periods. These data were compared by analysis of variance (ANOVA complemented by the Tukey's test. The TCP sample had higher surface roughness and lower density. The adherence and growth of FMM1 cells on samples from all groups was studied. Even though the different calcium based ceramics exhibited properties which made them suitable as bone substitutes, those with higher levels of β-TCP revealed improved cell growth on their surfaces. These observations indicated two-phase calcium phosphate based materials with a β-TCP surface layer to be a promising bone substitute.

  7. Calcium supplement ingestion may alter lumbar spine bone mineral density measurement.

    Science.gov (United States)

    Krueger, Diane; Checovich, Mary; Gemar, Dessa; Wei, Xiaodan; Binkley, Neil

    2006-01-01

    Densitometry centers commonly request patients abstain from ingesting calcium supplements prior to dual-energy X-ray absorptiometry (DXA) examination to avoid interference with bone mineral density (BMD) measurement. However, it is not clear that this practice is necessary. This study assessed the impact of recent calcium supplement intake on lumbar spine BMD measurement. The phase 1 experiment demonstrated BMD differences when placing a supplement over various areas of two encapsulated phantoms. To determine whether these results were clinically relevant, the phase 2 study enrolled 36 subjects who received spine scans before and after random assignment to ingest one Citracal, OsCal or People's Choice tablet providing 315, 500, and 600 mg of elemental calcium, respectively. The phase 3 study evaluated 15 subjects that had three spine scans with repositioning between to establish BMD precision, and then ingested a calcium carbonate tablet. Post-dosing scans were performed 15 and 30 minutes after tablet ingestion. The difference in L1-L4 BMD on subsequent scans was compared with the study derived least significant change (LSC) of 0.028 g/cm(2). In phase 2, L1-L4 BMD changes outside the LSC occurred in 36% of subjects with 47% having visualized tablets. Similarly, 33% of the phase 3 subjects demonstrated changes outside the LSC after calcium ingestion and 53% of the subjects in phase 3 had tablets visualized. Visualization of calcium tablets was not associated with BMD changes. In conclusion, calcium tablet intake may affect measured L1-L4 BMD within 30 minutes of ingestion. As such, it is appropriate to request patients abstain from calcium tablet ingestion prior to a spine DXA examination.

  8. Choice of osteoplastic materials for bone regeneration in the treatment of patients with generalized periodontitis with diabetes mellitus tape 2.

    Directory of Open Access Journals (Sweden)

    Gudaryan A.A.

    2014-11-01

    Full Text Available The article presents the results of a comparative study of using osteoinductive and osteoconductive material for bone osteoplastic grafting used to perform operations in the treatment of 60 patients with generalized periodontitis with diabetes mellitus type 2. It was found that by using different types of materials osteoplastic bone growth occurs differently. It was found that in preserved walls of bone pockets a mixture of osteoinductive material «Bio-Oss», combined with osteoconductive material osteoplastic «BondBone» prepared in platelet-rich plasma using collagen membranes «Bio-Gide» is enough and appropriate to use. This technique allowed achieving full recovery of bone in 86.2% of patients bone defects with. It was found that by using natural osteoplastic material «Bio-Oss» with extensive periodontal regeneration of alveolar bone defects in patients with generalized periodontitis associated with diabetes mellitus type 2 it is necessary to use membranes of polylactic acid to prevent migration of particles of osteoplastic material in the wound.

  9. Demineralized bone matrix as a bone tissue engineering scaffold material%骨组织工程支架材料:脱矿骨基质

    Institute of Scientific and Technical Information of China (English)

    陈海霞; 谢志刚

    2014-01-01

    BACKGROUND:Demineralized bone matrix as bone tissue engineering biological scaffold material is more researched currently, which has osteoinductive and osteoconductive. OBTECTIVE:To summarize the development of demineralized bone matrix as bone tissue engineering scaffold material and to prospect its trend. METHODS:The relative literatures addressing demineralized bone matrix as bone tissue engineering scaffold material published between January 1965 and May 2013 in PubMed database, Chinese Biomedical Database, Wanfang Database and FMJS database were searched by the first author. The key words were“demineralized bone matrix, scaffold material, growth factor, cells, drugs”in English and Chinese. According to the inclusion criteria, repetitive researches were excluded, and final y 34 articles were included. RESULTS AND CONCLUSION:Scaffold material is the key composition of tissue engineered bone, and only demineralized bone matrix has both osteoinductive and osteoconductive properties which cannot only provide space for bone repair, but also can be combined with bioactive factors, living cells, antibiotics in vitro to construct bone graft thereby promoting healing of bone defects. However, this technique is also facing some problems to be solved such as the ratio of demineralized bone matrix and various substances, disinfection, preservation of osteogenetic activity and antigenicity elimination. Sufficiently understanding demineralized bone matrix as bone tissue engineering scaffold can provide a theoretical basis for its clinical service.%背景:脱矿骨基质是目前研究较多的具备骨诱导及骨引导的生物支架材料之一。目的:总结脱矿骨基质作为骨组织工程支架材料的研究进展,并展望其发展趋势。  方法:由第一作者检索1965年1月至2013年5月PubMed数据库、中国生物医学数据库、万方数据库及FMJS数据库有关脱矿骨基质及其作为骨组织工程支架材料的相关文

  10. Obesity-related changes in bone structural and material properties in hyperphagic OLETF rats and protection by voluntary wheel running

    Science.gov (United States)

    We conducted a study to examine how the development of obesity and the associated insulin resistance affect bone structural and material properties, and bone formation and resorption markers in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat model. This was a 36-week study of sedentary, hyperphag...

  11. Growth, survival and bone alterations in Piaractus mesopotamicus larvae under different rearing protocols

    Directory of Open Access Journals (Sweden)

    David Roque Hernández

    2015-09-01

    Full Text Available The pacu (Piaractus mesopotamicus is a neotropical freshwater fish. It is one of the most important species farmed in areas of the Parana and Paraguay Rivers basins. The effects of different rearing protocols on growth, survival and incidence of skeletal malformations in pacu larvae were analyzed. A total of six experimental treatments were considered, consisting of: a semi-intensive larviculture (LS in ponds; intensive larviculture (LIn in laboratory (both LS and LIn until 60 days of life; and mixed larviculture, with 20 days of semi-intensive larviculture into cages in ponds after 14 (L1, 21 (L2, 33 (L3 or 40 (L4 days of laboratory larviculture. At the end of the experimental period, LSlarvae showed higher growth rate, with average weight values (2.28g and total length (TL-48.20mm statistically higher than the rest (P1 to L4 treatments showed intermediate growth values, without differences between them (P>0.05, while LIn presented the lowest growth (PS, that presented a significantly lower value (17.5%, PIn and L1 presented the lowest incidence. In no case, visible morphological alterations were found. This study shows that prolonging pacu rearing under laboratory conditions at high densities improves temporal availability and survival of juvenile without affecting growth or subsequent osteological development of fish.

  12. Microstructure, cytotoxicity and corrosion of powder-metallurgical iron alloys for biodegradable bone replacement materials

    Energy Technology Data Exchange (ETDEWEB)

    Wegener, Bernd; Sievers, Birte; Utzschneider, Sandra; Mueller, Peter; Jansson, Volkmar [Department of Orthopedic Surgery, Ludwig-Maximilians-University of Munich, Marchioninistrasse 15, 81377 Muenchen (Germany); Roessler, Sophie; Nies, Berthold [InnoTERE GmbH, Tatzberg 47, 01307 Dresden (Germany); Stephani, Guenter; Kieback, Bernd [Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM), Dresden Branch Lab, Winterbergstrasse 28, 01277 Dresden (Germany); Quadbeck, Peter, E-mail: peter.quadbeck@ifam-dd.fraunhofer.de [Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM), Dresden Branch Lab, Winterbergstrasse 28, 01277 Dresden (Germany)

    2011-12-15

    Up to now biodegradable bone implants with the ability of bearing high loads for the temporary replacement of bones or as osteosynthesis material are not available. Iron and iron based alloys have been identified as appropriate materials, since they combine high strength at medium corrosion rates. Thus, the aim of the present study is the development of a degradable iron based alloy with the perspective of using them as matrix material of cellular structures with biomechanical tailored properties. A powder metallurgical approach has been used to manufacture Fe-C, Fe-0.6P, Fe-1.6P, Fe-B and Fe-Ag samples, which have been tested with respect to their microstructure, their cytotoxicity, and their degradation rate. In order to determine the cytotoxicity of the material a monolayer culture of fibroblast and a perfusion chamber system has been chosen, which was recommended by the ISO 10993-5:1999 for biological testing of medical devices. It has been found, that in particular phosphorus features beneficial properties, since density and thus the strength of the material are increased. No corrosion inhibiting effects of phosphorus on the degradation rate have been found.

  13. Material-related effects of BMP-2 delivery systems on bone regeneration.

    Science.gov (United States)

    Hernández, Antonio; Sánchez, Esther; Soriano, Isabel; Reyes, Ricardo; Delgado, Araceli; Évora, Carmen

    2012-02-01

    Material-related effects of a brushite and a PLGA controlled release system loaded with two distinct doses of bone morphogenetic protein-2 (BMP-2) (3.5 and 17.5 μg), pre-encapsulated in poly(lactic-co-glycolic acid) (PLGA), were investigated in an intramedullary femur defect model in rabbits. The systems were characterized in vitro and in vivo over 12 weeks in terms of morphology, release kinetics, porosity, molecular weight, and composition using scanning electron microscopy, mercury porosimetry, radioactivity counting, X-ray diffractometry, differential scanning calorimetry, and gel permeation chromatography. During the experimental period the investigated systems underwent significant changes in vitro as well as in vivo. It should be stressed that the two in vitro release patterns were similar, however in vivo parallel profiles were observed with a higher burst effect for BMP-2 in the PLGA system. The PLGA system degraded and disintegrated significantly faster than the brushite system, which suffered slowly progressing external erosion and, additionally, material resorption by osteoclasts in vivo. The consequences of this were reflected in the degree of bone regeneration. Although a sustained delivery of BMP-2 was achieved with both systems, the brushite construct, independent of the loaded growth factor dose, failed to consistently induce defect repair, a result attributed to its slow resorption rate. In contrast, the PLGA system resulted in complete regeneration with mature trabecular bone formation 8 weeks after implantation.

  14. Study on β-TCP Coated Porous Mg as a Bone Tissue Engineering Scaffold Material

    Institute of Scientific and Technical Information of China (English)

    Fang Geng; Lili Tan; Bingchun Zhang; Chunfu Wu; Yonglian He; Jingyu Yang; Ke Yang

    2009-01-01

    Three-dimensional honeycomb-structured magnesium (Mg) scaffolds with interconnected pores of accurately controlled pore size and porosity were fabricated by laser perforation technique. Biodegradable and bioactive β-tricalcium phosphate (β-TCP) coatings were prepared on the porous Mg to further improve its biocompatibility, and the biodegradation mechanism was simply evaluated in vitro. It was found that the mechanical properties of this type of porous Mg significantly depended on its porosity. Elastic modulus and compressive strength similar to human bones could be obtained for the porous Mg with porosity of 42.6%-51%. It was observed that the human osteosarcoma cells (UMR106) were well adhered and proliferated on the surface of the β-TCP coated porous Mg, which indicates that the β-TCP coated porous Mg is promising to be a bone tissue engineering scaffold material.

  15. Altered membrane dynamics of quantum dot-conjugated integrins during osteogenic differentiation of human bone marrow derived progenitor cells.

    Science.gov (United States)

    Chen, Hongfeng; Titushkin, Igor; Stroscio, Michael; Cho, Michael

    2007-02-15

    Functionalized quantum dots offer several advantages for tracking the motion of individual molecules on the cell surface, including selective binding, precise optical identification of cell surface molecules, and detailed examination of the molecular motion without photobleaching. We have used quantum dots conjugated with integrin antibodies and performed studies to quantitatively demonstrate changes in the integrin dynamics during osteogenic differentiation of human bone marrow derived progenitor cells (BMPCs). Consistent with the unusually strong BMPC adhesion previously observed, integrins on the surface of undifferentiated BMPC were found in clusters and the lateral diffusion was slow (e.g., approximately 10(-11) cm2/s). At times as early as those after a 3-day incubation in the osteogenic differentiation media, the integrin diffusion coefficients increased by an order of magnitude, and the integrin dynamics became indistinguishable from that measured on the surface of terminally differentiated human osteoblasts. Furthermore, microfilaments in BMPCs consisted of atypically thick bundles of stress fibers that were responsible for restricting the integrin lateral mobility. Studies using laser optical tweezers showed that, unlike fully differentiated osteoblasts, the BMPC cytoskeleton is weakly associated with its cell membrane. Based on these findings, it appears likely that the altered integrin dynamics is correlated with BMPC differentiation and that the integrin lateral mobility is restricted by direct links to microfilaments.

  16. Platelet-rich plasma diminishes calvarial bone repair associated with alterations in collagen matrix composition and elevated CD34+ cell prevalence.

    Science.gov (United States)

    Giovanini, Allan Fernando; Deliberador, Tatiana Miranda; Gonzaga, Carla Castiglia; de Oliveira Filho, Marco Antonio; Göhringer, Isabella; Kuczera, Juliane; Zielak, João Cesar; de Andrade Urban, Cícero

    2010-06-01

    The interaction between platelets and both type I and III collagens plays an important role in modulating platelet adhesion and aggregation, also contributing to the chemotaxis of CD34+ cells. The interaction with type III collagen can maintain high levels of collagen and alter the biology of bone repair when the PRP is used. The aim of this study was to evaluate the effect of platelet-rich plasma (PRP) and autograft on the presence of type III and type I collagens, the ratio between them, as well as the presence of CD34+ progenitor cells, while comparing these results by means of a histomorphometric analysis of the bone tissue. Four bone defects (8.0mm in diameter and 2.0mm in depth) were produced on the calvarium of 23 rabbits. The surgical defects were treated with either autogenous bone grafts, autogenous bone grafts with PRP and PRP alone. Animals were euthanized at 2, 4 or 6 weeks post-surgery. Histological, histomorphometric and immunohistochemical analyses were performed to assess repair time, as well as the expression of type I and III collagens, and number of progenitor CD34+ cells. Data were analyzed using the ANOVA and Student-Newman-Keuls test (alpha=5%). An enlarged granulation and medullary tissue areas in the PRP groups were observed. The use of PRP in this study hindered bone deposition, also enhanced type III to type I collagen ratio and the chemotaxis of CD34+ progenitor cells, similarly to a thrombogenic effect.

  17. Novel biocompatible polymeric blends for bone regeneration: Material and matrix design and development

    Science.gov (United States)

    Deng, Meng

    The first part of the work presented in this dissertation is focused on the design and development of novel miscible and biocompatible polyphosphazene-polyester blends as candidate materials for scaffold-based bone tissue engineering applications. Biodegradable polyesters such as poly(lactide-co-glycolide) (PLAGA) are among the most widely used polymeric materials for bone tissue engineering. However, acidic degradation products resulting from the bulk degradation mechanism often lead to catastrophic failure of the structure integrity, and adversely affect biocompatibility both in vitro and in vivo. One promising approach to circumvent these limitations is to blend PLAGA with other macromolecules that can buffer the acidic degradation products with a controlled degradation rate. Biodegradable polyphosphazenes (PPHOS), a new class of biomedical materials, have proved to be superior candidate materials to achieve this objective due to their unique buffering degradation products. A highly practical blending approach was adopted to develop novel biocompatible, miscible blends of these two polymers. In order to achieve this miscibility, a series of amino acid ester, alkoxy, aryloxy, and dipeptide substituted PPHOS were synthesized to promote hydrogen bonding interactions with PLAGA. Five mixed-substituent PPHOS compositions were designed and blended with PLAGA at different weight ratios producing candidate blends via a mutual solvent method. Preliminary characterization identified two specific side groups namely glycylglycine dipeptide and phenylphenoxy that resulted in improved blend miscibility and enhanced in vitro osteocompatibility. These findings led to the synthesis of a mixed-substituent polyphosphazene poly[(glycine ethyl glycinato)1(phenylphenoxy)1phosphazene] (PNGEGPhPh) for blending with PLAGA. Two dipeptide-based blends having weight ratios of PNGEGPhPh to PLAGA namely 25:75 (Matrix1) and 50:50 (Matrix2) were fabricated. Both of the blends were

  18. Characterising structural, mechanical and cytotoxic properties of coral-based composite material intended for bone implant applications

    Directory of Open Access Journals (Sweden)

    Angela Samper Gaitán

    2011-08-01

    Full Text Available Studies concerning the application of Porites asteroides coral for bone implant purposes have demonstrated the biological viability of its use. As a complement to previous research regarding the development of bone-powder based composite materials which are useful for such applications, this study was aimed at developing a coral powder-based composite material which would be able to satisfy the appropriate structural, mechanical and cytotoxic properties required for its use. A composite material made of coral powder, calcium sulphate powder and water was therefore developed, and its properties were tested in different compositions. The results showed how the resulting composite material had properties which were comparable to those of human cortical bone (from both a structural and mechanical point of view, as well as being non-toxic below a 0.35 mg/ml critical composite material concentration.

  19. Evaluation of bone substitute materials: comparison of flat-panel based volume CT to conventional multidetector CT.

    Science.gov (United States)

    Sauerbier, Sebastian; Duttenhoefer, Fabian; Sachlos, Elefterios; Haberstroh, Jörg; Scheifele, Christian; Wrbas, Karl-Thomas; Voss, Pit Jacob; Veigel, Egle; Smedek, Jörg; Ganter, Philip; Tuna, Taskin; Gutwald, Ralf; Palmowski, Moritz

    2013-10-01

    Over the last decade tissue engineering has emerged as a key factor in bone regeneration within the field of cranio-maxillofacial surgery. Despite this in vivo analysis of tissue-engineered-constructs to monitor bone rehabilitation are difficult to conduct. Novel high-resolving flat-panel based volume CTs (fp-VCT) are increasingly used for imaging bone structures. This study compares the potential value of novel fp-VCT with conventional multidetector CT (MDCT) based on a sheep sinus floor elevation model. Calcium-hydroxyapatite reinforced collagen scaffolds were populated with autologous osteoblasts and implanted into sheep maxillary sinus. After 8, 16 and 24 weeks MDCT and fp-VCT scans were performed to investigate the volume of the augmented area; densities of cancellous and compact bone were assessed as comparative values. fp-VCT imaging resulted in higher spatial resolution, which was advantageous when separating closely related anatomical structures (i.e. trabecular and compact bone, biomaterials). Fp-VCT facilitated imaging of alterations occurring in test specimens over time. fp-VCTs therefore displayed high volume coverage, dynamic imaging potential and superior performance when investigating superfine bone structures and bone remodelling of biomaterials. Thus, fp-VCTs may be a suitable instrument for intraoperative imaging and future in vivo tissue-engineering studies.

  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; Tran, Chieu D

    2013-11-01

    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 Na2 HPO4 . 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 1.9 times 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.

  1. Material rhetoric: spreading stones and showing bones in the study of prehistory.

    Science.gov (United States)

    Van Reybrouck, David; de Bont, Raf; Rock, Jan

    2009-06-01

    Since the linguistic turn, the role of rhetoric in the circulation and the popular representation of knowledge has been widely accepted in science studies. This article aims to analyze not a textual form of scientific rhetoric, but the crucial role of materiality in scientific debates. It introduces the concept of material rhetoric to understand the promotional regimes in which material objects play an essential argumentative role. It analyzes the phenomenon by looking at two students of prehistory from nineteenth-century Belgium. In the study of human prehistory and evolution, material data are either fairly abundant stone tools or very scarce fossil bones. These two types of material data stand for two different strategies in material rhetoric. In this article, the first strategy is exemplified by Aimé Rutot, who gathered great masses of eoliths (crudely chipped stones which he believed to be prehistoric tools). The second strategy is typified by the example of Julien Fraipont, who based his scientific career on only two Neanderthal skeletons. Rutot sent his "artifacts" to a very wide audience, while Fraipont showed his skeletons to only a few selected scholars. Unlike Rutot, however, Fraipont was able to monitor his audience's interpretation of the finds by means of personal contacts. What an archaeologist gains in reach, he or she apparently loses in control. In this article we argue that only those scholars who find the right balance between the extremes of reach and control will prove to be successful.

  2. Water plasticization of extruded material made from meat and bone meal and sodium caseinate.

    Science.gov (United States)

    Garcia, Rafael A; Onwulata, Charles I; Ashby, Richard D

    2004-06-16

    Meat and bone meal (MBM) is a high protein agricultural commodity that currently has few applications other than as an animal feed. Unmodified MBM has poor functional properties, due to its low solubility. Our results from pilot plant trials demonstrate that MBM can be extrusion-processed along with sodium caseinate to produce a useful plastic material. We developed this material for use as a dog chew toy. For this application, elastic modulus (stiffness) is a key characteristic. Our results detail the relationship between ambient relative humidity and equilibrium moisture content (MC) in the material. The influence of MC on the glass transition temperature and elastic modulus reflects the plasticization of this material by water. On the basis of a comparison to a commercially available dog chew, the range of stiffness achievable with our material, 0.25-2.50 GPa, encompasses the values appropriate for a dog chew. Our results show that a particular desired stiffness can be maintained by applying an edible moisture barrier to the surface of the material.

  3. Extracellular matrix production by nucleus pulposus and bone marrow stem cells in response to altered oxygen and glucose microenvironments.

    Science.gov (United States)

    Naqvi, Syeda M; Buckley, Conor T

    2015-12-01

    Bone marrow (BM) stem cells may be an ideal source of cells for intervertebral disc (IVD) regeneration. However, the harsh biochemical microenvironment of the IVD may significantly influence the biological and metabolic vitality of injected stem cells and impair their repair potential. This study investigated the viability and production of key matrix proteins by nucleus pulposus (NP) and BM stem cells cultured in the typical biochemical microenvironment of the IVD consisting of altered oxygen and glucose concentrations. Culture-expanded NP cells and BM stem cells were encapsulated in 1.5% alginate and ionically crosslinked to form cylindrical hydrogel constructs. Hydrogel constructs were maintained under different glucose concentrations (1, 5 and 25 mM) and external oxygen concentrations (5 and 20%). Cell viability was measured using the Live/Dead® assay and the production of sulphated glycosaminoglycans (sGAG), and collagen was quantified biochemically and histologically. For BM stem cells, IVD-like micro-environmental conditions (5 mM glucose and 5% oxygen) increased the accumulation of sGAG and collagen. In contrast, low glucose conditions (1 mM glucose) combined with 5% external oxygen concentration promoted cell death, inhibiting proliferation and the accumulation of sGAG and collagen. NP-encapsulated alginate constructs were relatively insensitive to oxygen concentration or glucose condition in that they accumulated similar amounts of sGAG under all conditions. Under IVD-like microenvironmental conditions, NP cells were found to have a lower glucose consumption rate compared with BM cells and may in fact be more suitable to adapt and sustain the harsh microenvironmental conditions. Considering the highly specialised microenvironment of the central NP, these results indicate that IVD-like concentrations of low glucose and low oxygen are critical and influential for the survival and biological behaviour of stem cells. Such findings may promote and accelerate

  4. Altering the Microenvironment to Promote Dormancy of Metastatic Breast Cancer Cell in a 3D Bone Culture System

    Science.gov (United States)

    2015-04-01

    postmenopausal women. If we obtain future funding, we plan to continue to characterize the matrix. Physical methods such as atomic force...metastasis tumor stage already contain DTC in their bone marrow [10]. Dormant cells apparently survive chemotherapy, radiation and adjuvant therapy , and may...drug for the treatment of osteoporosis . J Bone Miner Res 21(3):354–365 22. Mundy GR et al (2008) Cytokines and bone remodeling. In: Marus R et al (eds

  5. Alterations in archaeological bones thermally treated: structure and morphology; Alteraciones en huesos arqueologicos termicamente tratados: estructura y morfologia

    Energy Technology Data Exchange (ETDEWEB)

    Pijoan, C.M.; Mansilla, J.; Leboreiro, I. [Direccion de Antropologia Fisica, INAH, Gandhi s/n, Polanco, 11560 Mexico D. F. (Mexico); Lara, V.H. [Universidad Autonoma Metropolitana-lztapalapa, Michoacan esquina La Purisima, Apdo.Postal 55-534, Mexico D. F. (Mexico); Bosch, P. [Instituto de Investigaciones en Materiales, UNAM, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2004-07-01

    Archaeological bones found close to Mexico city (Tlatelcomila) have been characterized by X-ray Diffraction, Small Angle X-ray Spectroscopy and Scanning Electron Microscopy. These techniques, which are not conventionally used in archaeological research, provided useful information. The boiled bones were clearly distinguished from grilled bones. The degree of deterioration of the bone structure was quantified through parameters such as gyration radius or fractal dimension. The morphology followed the structural modifications and changes resulting from thermic exposure. (Author) 23 refs., 1 tab., 2 figs.

  6. Presurgical orthodontic decompensation alters alveolar bone condition around mandibular incisors in adults with skeletal Class III malocclusion.

    Science.gov (United States)

    Sun, Boyang; Tang, Jun; Xiao, Ping; Ding, Ying

    2015-01-01

    This study is to use cone beam computed tomography (CBCT) to acquire accurate radiographic images for alveolar bone in lower incisors and the change after presurgical orthodontic treatment. Seventeen patients with skeletal Class III malocclusion, ten normal occlusion subjects, and fifteen patients treated with orthodontic treatment and orthognathic surgery were included. CBCT images were obtained. The labial and lingual inclinations of mandibular incisors, the thickness of alveolar bone, the vertical alveolar height and root length were measured. Alveolar bone thickness at the apex in patients with skeletal Class III malocclusion was thinner than normal subjects. The vertical alveolar bone heights at labial and lingual sides in patients with skeletal Class III malocclusion were both reduced compared with normal subjects, especially at the labial side. There were statistically significant correlations between lower incisor inclination and alveolar bone morphology. After orthodontics, the incisors root apex was closer to the lingual side of alveolar bone. The alveolar bone thickness at apex was not statistically changed. The vertical alveolar bone heights at the labial and lingual sides were both significantly reduced especially the lingual side after presurgical orthodontic treatment. The root length was not significantly changed. In conclusion, the alveolar bone thickness at apex is thinner and the vertical alveolar height is reduced at the labial side. Forward movement of lower incisors during presurgical orthodontic treatment can render the lower incisors root apex closer to the lingual side and the vertical alveolar height is reduced.

  7. Characterization of wear in composite material orthopaedic implants. Part II: The implant/bone interface.

    Science.gov (United States)

    Albert, K; Schledjewski, R; Harbaugh, M; Bleser, S; Jamison, R; Friedrich, K

    1994-01-01

    Carbon fiber/PEEK polymer (C/PEEK) composite materials are being developed for use as orthopaedic implant materials. Wear is an issue of increasing importance in orthopaedic implants; particulate debris generated by the wearing of biomaterials may be a causal factor leading to osteolysis and implant loosening. Therefore, numerical and experimental studies were completed to characterize the wear of C/PEEK composite materials in comparison to current orthopaedic implant materials. Finite element analyses (FEA) of a composite material hip stem implanted in a femur and loaded at 890 N determined that peak contact stresses will occur at the proximal-medial and distal regions of the implant. These contact stresses were found to be below 1.0 MPa over most of the implant surface; however the peak stress in the proximal-medial region was 1.8 MPa and higher still at the distal portion of the stem. In vivo forces result in contact stress values up to 9.0 MPa. The composite implant exhibited 10-40% lower contact stresses in the distal region compared to a titanium-alloy implant of identical design. Composite material wear samples were slid against porous hydroxylapatite (HA) to simulate the stem/bone interface. An identical series of experiments was run for comparison to a current orthopaedic implant material--Ti6A14V titanium alloy. Two domains of motion were studied; a composite ring-on-HA disc large amplitude sliding wear test; and a composite pin-on-HA disc small amplitude fretting regimen. Nominal contact pressures during testing were 1.4 MPa and 7.6 MPa for sliding and fretting tests, respectively. Fretting and sliding abrasive wear tests resulted in the composite material exhibiting a lower wear rate than the titanium-alloy. The magnitude of the difference was greatly dependent on the contact pressures, sliding amplitudes, and counterface material properties.

  8. Synthesis and Characterization of Biocomposite BCP/Collagen for Bone Material Scaffold

    Directory of Open Access Journals (Sweden)

    Anjarsari Anjarsari

    2017-02-01

    Full Text Available AbstractBiphasic calcium phosphate (BCP widely used as implants and scaffolds in different orthopedic and dental application. The aim of this study was to determine synthesis and characteristics of biocomposite BCP/collagen as bone scaffold material. BCP/collagen was classified into three groups: 1 BCP/K5 (5% collagen in scaffold, 2 BCP/K10 (10% collagen in scaffold, and 3 BCP/K15 (15% collagen in scaffold. The samples were characterized by Fourier Transform Infrared (FTIR Spectroscopy, and Scanning Electron Microscope (SEM techniques. Overall, concentration of collagen was not significantly different to the spectrum. However, FTIR analysis shows the change intensity in bio-composite BCP/collagen. Collagen intensity Higher concentration when collagen concentration in scaffold higher. Morphology analysis of the scaffold showed significant differences in pore formation. BCP/K15 was showed pores formed in scaffold. Synthesis of composite BCP/collagen does not affect the spectrum of functional groups, but affects the formation of pores in the bone scaffold material.

  9. 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

  10. Bone response to machined and resorbable blast material titanium implants: an experimental study in rabbits.

    Science.gov (United States)

    Piattelli, Maurizio; Scarano, Antonio; Paolantonio, Michele; Iezzi, Giovanna; Petrone, Giovanna; Piattelli, Adriano

    2002-01-01

    The aim of the present study was a comparison of implants' responses to a machined surface and to a surface sandblasted with hydroxyapatite (HA) particles (resorbable blast material [RBM]). Threaded machined and RBM, grade 3, commercially pure, titanium, screw-shaped inplants were used in this study. Twenty-four New Zealand white mature male rabbits were used. The inplants were inserted into the articular femoral knee joint according to a previously described technique. Each rabbit received 2 inplants, 1 test (RBM) and 1 control (machined). A total of 48 implants (24 control and 24 test) were inserted. The rabbits were anesthetized with intramuscular injections of fluanisone (0.7 mg/ kg body weight) and diazepam (1.5 mg/kg b.wt.), and local anesthesia was given using 1 mL of 2% lidocaine/adrenalin solution. Two rabbits died in the postoperative course. Four animals were euthanatized with an overdose of intravenous pentobarbital after 1, 2, 3, and 4 weeks; 6 rabbits were euthanatized after 8 weeks. A total of 44 implants were retrieved. The specimens were processed with the Precise 1 Automated System to obtain thin ground sections. A total of 3 slides were obtained for each implant. The slides were stained with acid and basic fuchsin and toluidine blue. The slides were observed in normal transmitted light under a Leitz Laborlux microscope, and histomorphometric analysis was performed. With the machined implants, it was possible to observe the presence of bone trabeculae near the implant surface at low magnification. At higher magnification many actively secreting alkaline phosphatasepositive (ALP+) osteoblasts were observed. In many areas, a not yet mineralized matrix was present. After 4 to 8 weeks, mature bone appeared in direct contact with the implant surface, but in many areas a not yet mineralized osteoid matrix was interposed between the mineralized bone and implant surface. In the RBM implants, many ALP+ osteoblasts were present and in direct contact with

  11. Bone regeneration in 3D printing bioactive ceramic scaffolds with improved tissue/material interface pore architecture in thin-wall bone defect.

    Science.gov (United States)

    Shao, Huifeng; Ke, Xiurong; Liu, An; Sun, Miao; He, Yong; Yang, Xianyan; Fu, Jianzhong; Liu, Yanming; Zhang, Lei; Yang, Guojing; Xu, Sanzhong; Gou, Zhongru

    2017-03-13

    Three-dimensional (3D) printing bioactive ceramics have demonstrated alternative approaches to bone tissue repair, but an optimized materials system for improving the recruitment of host osteogenic cells into the bone defect and enhancing targeted repair of the thin-wall craniomaxillofacial defects remains elusive. Herein we systematically evaluated the role of side-wall pore architecture in the direct-ink-writing bioceramic scaffolds on mechanical properties and osteogenic capacity in rabbit calvarial defects. The pure calcium silicate (CSi) and dilute Mg-doped CSi (CSi-Mg6) scaffolds with different layer thickness and macropore sizes were prepared by varying the layer deposition mode from single-layer printing (SLP) to double-layer printing (DLP) and then by undergoing one-, or two-step sintering. It was found that the dilute Mg doping and/or two-step sintering schedule was especially beneficial for improving the compressive strength (~25‒104 MPa) and flexural strength (~6‒18 MPa) of the Ca-silicate scaffolds. The histological analysis for the calvarial bone specimens in vivo revealed that the SLP scaffolds had a high osteoconduction at the early stage (4 weeks) but the DLP scaffolds displayed a higher osteogenic capacity for a long time stage (8~12 weeks). Although the DLP CSi scaffolds displayed somewhat higher osteogenic capacity at 8 and 12 weeks, the DLP CSi-Mg6 scaffolds with excellent fracture resistance also showed appreciable new bone tissue ingrowth. These findings demonstrate that the side-wall pore architecture in 3D printed bioceramic scaffolds is required to optimize for bone repair in calvarial bone defects, and especially the Mg doping wollastontie is promising for 3D printing thin-wall porous scaffolds for craniomaxillofacial bone defect treatment.

  12. The application of micro-CT in monitoring bone alterations in tail-suspended rats in vivo

    Science.gov (United States)

    Luan, Hui-Qin; Sun, Lian-Wen; Huang, Yun-Fei; Wang, Ying; McClean, Colin J.; Fan, Yu-Bo

    2014-06-01

    Osteopenia is a pathological process that affects human skeletal health not only on earth but also in long-time spaceflight. Micro-computed tomography (micro-CT) is a nondestructive method for assessing both bone quantity and bone quality. To investigate the characteristics of micro-CT on evaluating the microgravity-induced osteopenia (e.g. early detection time and the sensitive parameters), the bone loss process of tail-suspended rats was monitored by micro-CT in this study. 8-Week-old female Sprague Dawley rats were divided into two groups: tail suspension (TS) and control (CON). Volumetric bone mineral density (vBMD) and microstructure of the femur and tibia were evaluated in vivo by micro-CT at 0, 7, 14, 22 days. Biomechanical properties of the femur and tibia were determined by three-point bending test. The ash weight of bone was also investigated. The results showed that (1) bone loss in the proximal tibia appeared earlier than in the distal femur. (2) On day 7, the percent bone volume (BV/TV) of the tibia 15.44% decreased significantly, and the trabecular separation (Tb.Sp) 30.29% increased significantly in TS group, both of which were detected earlier than other parameters. (3) Biomechanical properties (e.g. femur, -22.4% maximum load and -23.75% Young’s modulus vs. CON) and ash weight of the femur and tibia decreased significantly in the TS group in comparison to CON group. (4) vBMD of the femur and tibia were clearly related to bone ash and dry weight (r = 0.75-0.87, p bone loss induced by tail suspension, moreover, trabecular vBMD and other parameters might be used to evaluate bone strength. Therefore, micro-CT is a reliable and sensitive method for predicting unloading-induced bone loss in small animals.

  13. Development of a strain rate dependent material model of human cortical bone for computer-aided reconstruction of injury mechanisms.

    Science.gov (United States)

    Asgharpour, Zahra; Zioupos, Peter; Graw, Matthias; Peldschus, Steffen

    2014-03-01

    Computer-aided methods such as finite-element simulation offer a great potential in the forensic reconstruction of injury mechanisms. Numerous studies have been performed on understanding and analysing the mechanical properties of bone and the mechanism of its fracture. Determination of the mechanical properties of bones is made on the same basis used for other structural materials. The mechanical behaviour of bones is affected by the mechanical properties of the bone material, the geometry, the loading direction and mode and of course the loading rate. Strain rate dependency of mechanical properties of cortical bone has been well demonstrated in literature studies, but as many of these were performed on animal bones and at non-physiological strain rates it is questionable how these will apply in the human situations. High strain-rates dominate in a lot of forensic applications in automotive crashes and assault scenarios. There is an overwhelming need to a model which can describe the complex behaviour of bone at lower strain rates as well as higher ones. Some attempts have been made to model the viscoelastic and viscoplastic properties of the bone at high strain rates using constitutive mathematical models with little demonstrated success. The main objective of the present study is to model the rate dependent behaviour of the bones based on experimental data. An isotropic material model of human cortical bone with strain rate dependency effects is implemented using the LS-DYNA material library. We employed a human finite element model called THUMS (Total Human Model for Safety), developed by Toyota R&D Labs and the Wayne State University, USA. The finite element model of the human femur is extracted from the THUMS model. Different methods have been employed to develop a strain rate dependent material model for the femur bone. Results of one the recent experimental studies on human femur have been employed to obtain the numerical model for cortical femur. A

  14. Organic compound alteration during hypervelocity collection of carbonaceous materials in aerogel

    Science.gov (United States)

    Spencer, M. K.; Clemett, S. J.; Sandford, S. A.; McKay, D. S.; Zare, R. N.

    2009-03-01

    The NASA Stardust mission brought to Earth micron-size particles from the coma of comet 81P/Wild 2 using aerogel, a porous silica material, as the capture medium. A major challenge in understanding the organic inventory of the returned comet dust is identifying, unambiguously, which organic molecules are indigenous to the cometary particles, which are produced from carbon contamination in the Stardust aerogel, and which are cometary organics that have been modified by heating during the particle capture process. Here it is shown that 1) alteration of cometary organic molecules along impact tracks in aerogel is highly dependent on the original particle morphology, and 2) organic molecules on test-shot terminal particles are mostly preserved. These conclusions are based on two-step laser mass spectrometry (L2MS) examinations of test shots with organic-laden particles (both tracks in aerogel and the terminal particles themselves).

  15. Quantifying trabecular bone material anisotropy and orientation using low resolution clinical CT images: A feasibility study.

    Science.gov (United States)

    Nazemi, S Majid; Cooper, David M L; Johnston, James D

    2016-09-01

    Accounting for spatial variation of trabecular material anisotropy and orientation can improve the accuracy of quantitative computed tomography-based finite element (FE) modeling of bone. The objective of this study was to investigate the feasibility of quantifying trabecular material anisotropy and orientation using clinical computed tomography (CT). Forty four cubic volumes of interest were obtained from micro-CT images of the human radius. Micro-FE modeling was performed on the samples to obtain orthotropic stiffness entries as well as trabecular orientation. Simulated computed tomography images (0.32, 0.37, and 0.5mm isotropic voxel sizes) were created by resampling micro-CT images with added image noise. The gray-level structure tensor was used to derive fabric eigenvalues and eigenvectors in simulated CT images. For 'best case' comparison purposes, Mean Intercept Length was used to define fabric from micro-CT images. Regression was used in combination with eigenvalues, imaged density and FE to inversely derive the constants used in Cowin and Zysset-Curnier fabric-elasticity equations, and for comparing image derived fabric-elasticity stiffness entries to those obtained using micro-FE. Image derived eigenvectors (which indicated trabecular orientation) were then compared to orientation derived using micro-FE. When using clinically available voxel sizes, gray-level structure tensor derived fabric combined with Cowin's equations was able to explain 94-97% of the variance in orthotropic stiffness entries while Zysset-Curnier equations explained 82-88% of the variance in stiffness. Image derived orientation deviated by 4.4-10.8° from micro-FE derived orientation. Our results indicate potential to account for spatial variation of trabecular material anisotropy and orientation in subject-specific finite element modeling of bone using clinically available CT.

  16. P(3HB Based Magnetic Nanocomposites: Smart Materials for Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Everest Akaraonye

    2016-01-01

    Full Text Available The objective of this work was to investigate the potential application of Poly(3-hydroxybutyrate/magnetic nanoparticles, P(3HB/MNP, and Poly(3-hydroxybutyrate/ferrofluid (P(3HB/FF nanocomposites as a smart material for bone tissue repair. The composite films, produced using conventional solvent casting technique, exhibited a good uniform dispersion of magnetic nanoparticles and ferrofluid and their aggregates within the P(3HB matrix. The result of the static test performed on the samples showed that there was a 277% and 327% increase in Young’s modulus of the composite due to the incorporation of MNP and ferrofluid, respectively. The storage modulus of the P(3HBMNP and P(3HB/FF was found to have increased to 186% and 103%, respectively, when compared to neat P(3HB. The introduction of MNP and ferrofluid positively increased the crystallinity of the composite scaffolds which has been suggested to be useful in bone regeneration. The total amount of protein absorbed by the P(3HB/MNP and P(3HB/FF composite scaffolds also increased by 91% and 83%, respectively, with respect to neat P(3HB. Cell attachment and proliferation were found to be optimal on the P(HB/MNP and P(3HB/FF composites compared to the tissue culture plate (TCP and neat P(3HB, indicating a highly compatible surface for the adhesion and proliferation of the MG-63 cells. Overall, this work confirmed the potential of using P(3HB/MNP and P(3HB/FF composite scaffolds in bone tissue engineering.

  17. Differences in Bone Quality between High versus Low Turnover Renal Osteodystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Daniel S. [University of Kentucky, Lexington; Pienkowski, David [University of Kentucky, Lexington; Faugere, Marie-Claude [Albert B. Chandler Medical Center; Malluche, Hartmut H. [Albert B. Chandler Medical Center

    2012-01-01

    Abnormal bone turnover is common in chronic kidney disease (CKD), but its effects on bone quality remain unclear. This study sought to quantify the relationship between abnormal bone turnover and bone quality. Iliac crest bone biopsies were obtained from CKD-5 patients on dialysis with low (n=18) or high (n=17) turnover, and from volunteers (n=12) with normal turnover and normal kidney function. Histomorphometric methods were used to quantify the microstructural parameters; Fourier transform infrared spectroscopy and nanoindentation were used to quantify the material and mechanical properties in bone. Reduced mineral-to-matrix ratio, mineral crystal size, stiffness and hardness were observed in bone with high turnover compared to bone with normal or low turnover. Decreased cancellous bone volume and trabecular thickness were seen in bone with low turnover compared to bone with normal or high turnover. Bone quality, as defined by its microstructural, material, and mechanical properties, is related to bone turnover. These data suggest that turnover related alterations in bone quality may contribute to the known diminished mechanical competence of bone in CKD patients, albeit from different mechanisms for bone with high (material abnormality) vs. low (microstructural alteration) turnover. The present findings suggest that improved treatments for renal osteodystrophy should seek to avoid low or high bone turnover and aim for turnover rates as close to normal as possible.

  18. Free-Electron Laser Wavelength-Selective Materials Alteration and Photoexcitation Spectroscopy

    Science.gov (United States)

    Tolk, Norman.

    1996-10-01

    The Vanderbilt Free-Electron Laser's (FEL) tunability (2-10um), high intensity (15 MW) and short pulse structure (1 ps) make it ideal for studying (a) the electronic and vibrational structure of small and wide band gap semiconductors, and (b) non-thermal wavelength-selective materials alteration. Spectroscopic studies footnote Work performed with R.G. Albridge, A.V. Barnes, J. Gilligan, G. Margaritondo, and J. T. McKinley of semiconductor electronic and nonlinear optical properties will be discussed. Recent two-photon absorption measurements in Ge were the first verification of a two-decades old prediction by Bassani and Hassan that the indirect two-photon absorption in Ge would be an LO-phonon assisted process. They also provided valuable insight into the effect of inversion symmetry on two-photon absorption. The strength of germanium's indirect gap two-photon absorption was found to be 1000 times weaker than the direct absorption. The FEL has greatly facilitated internal photoemission (IPE) heterojunction band discontinuity measurements. This technique is a photocurrent excitation spectroscopy that provides a direct measurement of the discontinuity without resorting to complex modeling. A photocurrent threshold is observed as the photon energy exceeds the discontinuity energy. IPE has long been used in the field of Schottky barriers but has largely been ignored in the case of semiconductor heterojunctions because of insufficiently intense light sources. We will discuss IPE measurements of InP/GaInAs and a-Ge/GaAs. Our low-temperature IPE discontinuity measurements reach accuracies better than #5 meV. Another important area of materials research at the FEL concerns identification of wavelength-selective mechanisms for materials alteration. Vibrational modes associated with defects and impurities provide a means of introducing a non thermal distribution of energy into a solid. We have used the FEL to demonstrate strongly wavelength-selective ablation near the C

  19. The sealing ability of novel Kryptonite adhesive bone cement as a retrograde filling material

    Science.gov (United States)

    Uzun, İsmail; Keskin, Cangül; Güler, Buğra

    2016-01-01

    Background. This study evaluated the ability of Kryptonite bone cement in sealing retrograde cavities. Methods. The root canals of one hundred extracted human maxillary incisor teeth were instrumented up to master apical file #40 using Mtwo rotary system and obturated with gutta-percha and AHPlus sealer by cold lateral compaction method. The specimens were assigned to one control group and four experimental groups based on the retrograde filling materials (n=20). The specimens were immersed in 0.5% Rhodamine B solution for 48h. Then the specimens were divided longitudinally into two parts and the depth of dye penetration was assessed under ×10 magnification. Data were analyzed using one-way ANOVA and Bonferroni tests. Results. There were statistically significant difference between the experimental groups and the control group (P0.05). Conclusion. Kryptonite cement provided optimal apical seal in a manner similar to MTA, amalgam and IRM when used as a retrograde filling cement. PMID:27651886

  20. Advanced bioimaging technologies in assessment of the quality of bone and scaffold materials. Techniques and applications

    Energy Technology Data Exchange (ETDEWEB)

    Qin Ling; Leung, Kwok Sui (eds.) [Chinese Univ. of Hong Kong (China). Dept. of Orthopaedics and Traumatology; Genant, H.K. [California Univ., San Francisco, CA (United States); Griffith, J.F. [Chinese Univ. of Hong Kong (China). Dept. of Radiology and Organ Imaging

    2007-07-01

    This book provides a perspective on the current status of bioimaging technologies developed to assess the quality of musculoskeletal tissue with an emphasis on bone and cartilage. It offers evaluations of scaffold biomaterials developed for enhancing the repair of musculoskeletal tissues. These bioimaging techniques include micro-CT, nano-CT, pQCT/QCT, MRI, and ultrasound, which provide not only 2-D and 3-D images of the related organs or tissues, but also quantifications of the relevant parameters. The advance bioimaging technologies developed for the above applications are also extended by incorporating imaging contrast-enhancement materials. Thus, this book will provide a unique platform for multidisciplinary collaborations in education and joint R and D among various professions, including biomedical engineering, biomaterials, and basic and clinical medicine. (orig.)

  1. Infection of chicken bone marrow mononuclear cells with subgroup J avian leukosis virus inhibits dendritic cell differentiation and alters cytokine expression.

    Science.gov (United States)

    Liu, Di; Qiu, Qianqian; Zhang, Xu; Dai, Manman; Qin, Jianru; Hao, Jianjong; Liao, Ming; Cao, Weisheng

    2016-10-01

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus known to induce tumor formation and immunosuppression in infected chickens. One of the organs susceptible to ALV-J is the bone marrow, from which specialized antigen-presenting cells named dendritic cells (BM-DCs) are derived. Notably, these cells possess the unique ability to induce primary immune responses. In the present study, a method of cultivating and purifying DCs from chicken bone marrow in vitro was established to investigate the effects of ALV-J infection on BM-DC differentiation or generation. The results indicated that ALV-J not only infects the chicken bone marrow mononuclear cells but also appears to inhibit the differentiation and maturation of BM-DCs and to trigger apoptosis. Moreover, substantial reductions in the mRNA expression of TLR1, TLR2, TLR3, MHCI, and MHCII and in cytokine production were detected in the surviving BM-DCs following ALV-J infection. These findings indicate that ALV-J infection disrupts the process of bone marrow mononuclear cell differentiation into BM-DCs likely via altered antigen presentation, resulting in a downstream immune response in affected chickens.

  2. Higher number of pentosidine cross-links induced by ribose does not alter tissue stiffness of cancellous bone

    Energy Technology Data Exchange (ETDEWEB)

    Willems, Nop M.B.K., E-mail: n.willems@acta.nl [Dept. of Orthodontics, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University, Gustav Mahlerlaan 3004, 1081 LA Amsterdam (Netherlands); Dept. of Oral Cell Biology and Functional Anatomy, MOVE Research Institute, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University, Gustav Mahlerlaan 3004, 1081 LA Amsterdam (Netherlands); Langenbach, Geerling E.J. [Dept. of Oral Cell Biology and Functional Anatomy, MOVE Research Institute, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University, Gustav Mahlerlaan 3004, 1081 LA Amsterdam (Netherlands); Stoop, Reinout [Dept. of Metabolic Health Research, TNO, P.O. Box 2215, 2301 CE Leiden (Netherlands); Toonder, Jaap M.J. den [Dept. of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Mulder, Lars [Dept. of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Zentner, Andrej [Dept. of Orthodontics, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University, Gustav Mahlerlaan 3004, 1081 LA Amsterdam (Netherlands); Everts, Vincent [Dept. of Oral Cell Biology and Functional Anatomy, MOVE Research Institute, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University, Gustav Mahlerlaan 3004, 1081 LA Amsterdam (Netherlands)

    2014-09-01

    The role of mature collagen cross-links, pentosidine (Pen) cross-links in particular, in the micromechanical properties of cancellous bone is unknown. The aim of this study was to examine nonenzymatic glycation effects on tissue stiffness of demineralized and non-demineralized cancellous bone. A total of 60 bone samples were derived from mandibular condyles of six pigs, and assigned to either control or experimental groups. Experimental handling included incubation in phosphate buffered saline alone or with 0.2 M ribose at 37 °C for 15 days and, in some of the samples, subsequent complete demineralization of the sample surface using 8% EDTA. Before and after experimental handling, bone microarchitecture and tissue mineral density were examined by means of microcomputed tomography. After experimental handling, the collagen content and the number of Pen, hydroxylysylpyridinoline (HP), and lysylpyridinoline (LP) cross-links were estimated using HPLC, and tissue stiffness was assessed by means of nanoindentation. Ribose treatment caused an up to 300-fold increase in the number of Pen cross-links compared to nonribose-incubated controls, but did not affect the number of HP and LP cross-links. This increase in the number of Pen cross-links had no influence on tissue stiffness of both demineralized and nondemineralized bone samples. These findings suggest that Pen cross-links do not play a significant role in bone tissue stiffness. - Highlights: • The assessment of effects of glycation in bone using HPLC, microCT, and nanoindentation • Ribose incubation: 300‐fold increase in the number of pentosidine cross-links • 300‐fold increase in the number of pentosidine cross-links: no changes in bone tissue stiffness.

  3. Guided bone regeneration for immediate non-submerged implant placement using bioabsorbable materials in Beagle dogs.

    Science.gov (United States)

    Brunel, G; Benqué, E; Elharar, F; Sansac, C; Duffort, J F; Barthet, P; Baysse, E; Miller, N

    1998-10-01

    The aim of the present study was to evaluate the combined application of different bioabsorbable materials for healing of residual peri-implant defects after placement of non-submerged implants into fresh extraction sockets. Second and third mandibular premolars were extracted from 10 Beagle dogs, the coronal part of the distal sockets were surgically enlarged and this was followed by immediate placement of specially designed hollow-screw non-submerged dental implants. For each animal, the coronal peri-implant defects were further treated with one of the 4 following procedures: 1) no treatment, control site; 2) grafting with porous hydroxyapatite (HA); 3) collagen membrane tightly secured around the implant and over the defect and 4) grafting with HA covered with a collagen membrane. After 16 weeks of healing, specimens were removed from the mandibule and prepared for a histomorphometric evaluation. The bone-to-implant contact length (BIC) was measured and compared amongst the different treatment modalities. In the defect area, the irregular bone regeneration was similar between all the treatment procedures (P > 0.10). In the sites covered with a collagen membrane alone, the total BIC (47%) was greater than in control sites (28.7%, P < 0.05) or sites grafted with HA (22.2%, P < 0.02). Total BIC in sites treated with the HA-membrane combination (43%) was only significantly different from sites treated with HA (P < 0.05). It is concluded that the use of bioabsorbable materials results in a limited increase of osseointegration when used in conjunction with immediate placement of non-submerged implants, although the principle of the one stage surgical approach can be maintained.

  4. Phantom-less bone mineral density (BMD) measurement using dual energy computed tomography-based 3-material decomposition

    Science.gov (United States)

    Hofmann, Philipp; Sedlmair, Martin; Krauss, Bernhard; Wichmann, Julian L.; Bauer, Ralf W.; Flohr, Thomas G.; Mahnken, Andreas H.

    2016-03-01

    Osteoporosis is a degenerative bone disease usually diagnosed at the manifestation of fragility fractures, which severely endanger the health of especially the elderly. To ensure timely therapeutic countermeasures, noninvasive and widely applicable diagnostic methods are required. Currently the primary quantifiable indicator for bone stability, bone mineral density (BMD), is obtained either by DEXA (Dual-energy X-ray absorptiometry) or qCT (quantitative CT). Both have respective advantages and disadvantages, with DEXA being considered as gold standard. For timely diagnosis of osteoporosis, another CT-based method is presented. A Dual Energy CT reconstruction workflow is being developed to evaluate BMD by evaluating lumbar spine (L1-L4) DE-CT images. The workflow is ROI-based and automated for practical use. A dual energy 3-material decomposition algorithm is used to differentiate bone from soft tissue and fat attenuation. The algorithm uses material attenuation coefficients on different beam energy levels. The bone fraction of the three different tissues is used to calculate the amount of hydroxylapatite in the trabecular bone of the corpus vertebrae inside a predefined ROI. Calibrations have been performed to obtain volumetric bone mineral density (vBMD) without having to add a calibration phantom or to use special scan protocols or hardware. Accuracy and precision are dependent on image noise and comparable to qCT images. Clinical indications are in accordance with the DEXA gold standard. The decomposition-based workflow shows bone degradation effects normally not visible on standard CT images which would induce errors in normal qCT results.

  5. Influence of carbonyl stress on rheological alterations of blood materials and decarbonylation effect of glutathione

    Institute of Scientific and Technical Information of China (English)

    彭密军; 蔡建光; 贺洪; 龚萍; 李国林; 汤婷; 朱泽瑞; 印大中

    2008-01-01

    The effects of various toxic carbonyls such as malondialdehyde(MDA),a secondary product of lipid peroxidation,and other aldehydes on rheological parameters and their relationship with aging-associated alterations were studied.Both MDA and glutaraldehyde(Glu) in different concentrations significantly increase viscosity,plastic viscosity and yield stress of human plasma and erythrocyte suspensions.MDA(20 mmol/L) reduces sharply the typical fluorescence of proteins(excitation 280 nm/emission 350 nm),and produces age pigment-like fluorescence with a strong emission peak at 460 nm when excites at 395 nm by only being incubated for some hours.In contrast,Glu decreases merely the fluorescence of proteins without producing age pigment-like fluorescence.These data suggest interestingly that the MDA-induced gradual protein cross linking seems to form from different mechanisms compared to the fast rheological changes of blood materials which may take place either in acute and chronic diseases or during aging.On the other hand,MDA induces various deleterious alterations of erythrocytes whereas glutathione(GSH) inhibits the MDA-related carbonyl stress in a concentration-dependent manner.The results indicate that carbonyl-amino reaction exists in the blood widely and GSH has the ability to interrupt or reverse this reaction in a certain way.It implies that carbonyl stress may be one of the important factors in blood stasis and suggests a theoretical and practical approach in anti-stresses and anti-aging.

  6. Augmentation of Bone Tunnel Healing in Anterior Cruciate Ligament Grafts: Application of Calcium Phosphates and Other Materials

    Directory of Open Access Journals (Sweden)

    F. R. Baxter

    2010-01-01

    Full Text Available Bone tunnel healing is an important consideration after anterior cruciate ligament (ACL replacement surgery. Recently, a variety of materials have been proposed for improving this healing process, including autologous bone tissue, cells, artificial proteins, and calcium salts. Amongst these materials are calcium phosphates (CaPs, which are known for their biocompatibility and are widely commercially available. As with the majority of the materials investigated, CaPs have been shown to advance the healing of bone tunnel tissue in animal studies. Mechanical testing shows fixation strengths to be improved, particularly by the application of CaP-based cement in the bone tunnel. Significantly, CaP-based cements have been shown to produce improvements comparable to those induced by potentially more complex treatments such as biologics (including fibronectin and chitin and cultured cells. Further investigation of CaP-based treatment in the bone tunnels during ACL replacement is therefore warranted in order to establish what improvements in healing and resulting clinical benefits may be achieved through its application.

  7. PMMA-hydroxyapatite composite material retards fatigue failure of augmented bone compared to augmentation with plain PMMA: in vivo study using a sheep model.

    Science.gov (United States)

    Arabmotlagh, Mohammad; Bachmaier, Samuel; Geiger, Florian; Rauschmann, Michael

    2014-11-01

    Polymethylmethacrylate (PMMA) is the most commonly used void filler for augmentation of osteoporotic vertebral fracture, but the differing mechanical features of PMMA and osteoporotic bone result in overload and failure of adjacent bone. The aim of this study was to compare fatigue failure of bone after augmentation with PMMA-nanocrystalline hydroxyapatite (HA) composite material or with plain PMMA in a sheep model. After characterization of the mechanical properties of a composite material consisting of PMMA and defined amounts (10, 20, and 30% volume fraction) of HA, the composite material with 30% volume fraction HA was implanted in one distal femur of sheep; plain PMMA was implanted in the other femur. Native non-augmented bone served as control. Three and 6 months after implantation, the augmented bone samples were exposed to cyclic loading and the evolution of damage was investigated. The fatigue life was highest for the ovine native bone and lowest for bone-PMMA specimens. Bone-composite specimens showed significantly higher fatigue life than the respective bone-PMMA specimens in both 3- and 6-month follow-up groups. These results suggest that modification of mechanical properties of PMMA by addition of HA to approximate those of cancellous bone retards fatigue failure of the surrounding bone compared to augmented bone with plain PMMA.

  8. A high mixed protein diet reduces body fat without altering the mechanical properties of bone in female rats.

    Science.gov (United States)

    Pye, Kathleen M; Wakefield, Andrew P; Aukema, Harold M; House, James D; Ogborn, Malcolm R; Weiler, Hope A

    2009-11-01

    Long-term consumption of high-protein (HP) diets at 35% of energy is postulated to negatively influence bone health. Previous studies have not comprehensively examined the biochemical, physical, and biomechanical properties of bone required to arrive at this conclusion. Our objective in this study was to examine the long-term effect of a HP diet on bone metabolism, mass, and strength in rats. Adult female Sprague-Dawley rats (n = 80) were randomized to receive for 4, 8, 12, or 17 mo a normal-protein (NP) control diet (15% of energy) or a HP diet (35% of energy). Diets were balanced for calcium because the protein sources were rich in calcium. At each time point, measurements included weight, body composition, and bone mass using dual-energy X-ray absorptiometry, mechanical strength at the mid-diaphysis of femur and tibia, microarchitecture of femurs using microcomputerized tomography and serum osteocalcin, carboxy-terminal crosslinks of type I collagen (CTX), insulin-like growth factor-1 (IGF-1), leptin, and adiponectin. Effects of diet, time, and their interaction were tested using factorial ANOVA. The HP diet resulted in lower body weight, total body, and abdominal fat and higher lean mass. Serum leptin and adiponectin were greater in HP-fed than in NP-fed rats, but IGF-1 did not differ between the groups. Whereas the HP diet resulted in higher relative bone mineral content (g/kg) in the femur, tibia, and vertebrae, serum osteocalcin and CTX and bone internal architecture and biomechanical strength were unaffected. In conclusion, HP diets at 35% of energy lower body fat content without hindering the mechanical and weight-bearing properties of bone.

  9. The bone regenerative effect of platelet-rich plasma in combination with an osteoconductive material in rat cranial defects.

    NARCIS (Netherlands)

    Plachokova, A.S.; Dolder, J. van den; Stoelinga, P.J.W.; Jansen, J.A.

    2006-01-01

    The effect of platelet-rich plasma (PRP) on bone regeneration, in combination with an osteoconductive material, was evaluated in a rat model. Cranial defects, 6.2 mm in diameter, were filled with HA/beta-TCP particles, HA/beta-TCP particles combined with PRP and HA/beta-TCP particles combined with P

  10. Effect of alteration in organic material of the occlusal caries on DIAGNOdent readings.

    Science.gov (United States)

    Mendes, Fausto Medeiros; Pinheiro, Sérgio Luiz; Bengtson, Antonio Lucindo

    2004-01-01

    DIAGNOdent is a laser fluorescence device used for dental caries diagnosis in occlusal and smooth surfaces. Despite the promising preliminary results, the molecules involved in the increase of fluorescence in carious lesions remain unclear. The aim of this study was to compare the laser fluorescence readings before and after changes in the organic material of occlusal carious lesions in primary teeth. Twenty-four primary molars stored in saline solution with at least one site with occlusal caries were divided into two groups. The control group had 17 sites with caries and the experimental one had 16 sites. The carious lesions were measured with laser fluorescence. The experimental samples were then removed from the storage solution and immersed in a 2% sodium hypochlorite solution for 24 hours. After washing with water, the teeth were measured again with the laser fluorescence device. The teeth of the control group were submitted to the same procedures, but saline solution was used instead of the sodium hypochlorite solution. A statistically significant reduction in the mean of the readings after immersion in the two tested solutions compared with the initial readings was observed in both groups, but the decrease was statistically higher in the experimental group (p < 0.0001). In this study, the data indicate that changes in the fluorescence of carious lesions measured by the laser fluorescence are mainly due to the organic content alterations rather than to the mineral loss.

  11. Mechanical and material properties of cortical and trabecular bone from cannabinoid receptor-1-null (Cnr1(-/-)) mice.

    Science.gov (United States)

    Khalid, Aysha B; Goodyear, Simon R; Ross, Ruth A; Aspden, Richard M

    2016-10-01

    The endocannabinoid system is known for its regulatory effects on bone metabolism through the cannabinoid receptors, Cnr1 and Cnr2. In this study we analysed the mechanical and material properties of long bones from Cnr1(-/-) mice on a C57BL/6 background. Tibiae and femora from 5- and 12-week-old mice were subjected to three-point bending to measure bending stiffness and yield strength. Elastic modulus, density and mineral content were measured in the diaphysis. Second moment of area (MOA2), inner and outer perimeters of the cortical shaft and trabecular fractional bone volume (BV/TV) were measured using micro-CT. In Cnr1(-/-) males and females at both ages the bending stiffness was reduced due to a smaller MOA2. Bone from Cnr1(-/-) females had a greater modulus than wild-type controls, although no differences were observed in males. BV/TV of 12-week-old Cnr1(-/-) females was greater than controls, although no difference was seen at 5-weeks. On the contrary, Cnr1(-/-) males had the same BV/TV as controls at 12-weeks while they had significantly lower values at 5-weeks. This study shows that deleting Cnr1 decreases the amount of cortical bone in both males and females at 12-weeks, but increases the amount of trabecular bone only in females.

  12. Carboxymethyl cellulose-hydroxyapatite hybrid hydrogel as a composite material for bone tissue engineering applications.

    Science.gov (United States)

    Pasqui, Daniela; Torricelli, Paola; De Cagna, Milena; Fini, Milena; Barbucci, Rolando

    2014-05-01

    Natural bone is a complex inorganic-organic nanocomposite material, in which hydroxyapatite (HA) nanocrystals and collagen fibrils are well organized into hierarchical architecture over several length scales. In this work, we reported a new hybrid material (CMC-HA) containing HA drown in a carboxymethylcellulose (CMC)-based hydrogel. The strategy for inserting HA nanocrystals within the hydrogel matrix consists of making the freeze-dried hydrogel to swell in a solution containing HA microcrystals. The composite CMC-HA hydrogel has been characterized from a physicochemical and morphological point of view by means of FTIR spectroscopy, rheological measurements, and field emission scanning electron microscopy (FESEM). No release of HA was measured in water or NaCl solution. The distribution of HA crystal on the surface and inside the hydrogel was determined by time of flight secondary ion mass spectrometry (ToF-SIMS) and FESEM. The biological performance of CMC-HA hydrogel were tested by using osteoblast MG63 line and compared with a CMC-based hydrogel without HA. The evaluation of osteoblast markers and gene expression showed that the addition of HA to CMC hydrogel enhanced cell proliferation and metabolic activity and promoted the production of mineralized extracellular matrix.

  13. Porous biomorphic silicon carbide ceramics coated with hydroxyapatite as prospective materials for bone implants.

    Science.gov (United States)

    Gryshkov, Oleksandr; Klyui, Nickolai I; Temchenko, Volodymyr P; Kyselov, Vitalii S; Chatterjee, Anamika; Belyaev, Alexander E; Lauterboeck, Lothar; Iarmolenko, Dmytro; Glasmacher, Birgit

    2016-11-01

    Porous and cytocompatible silicon carbide (SiC) ceramics derived from wood precursors and coated with bioactive hydroxyapatite (HA) and HA-zirconium dioxide (HA/ZrO2) composite are materials with promising application in engineering of bone implants due to their excellent mechanical and structural properties. Biomorphic SiC ceramics have been synthesized from wood (Hornbeam, Sapele, Tilia and Pear) using a forced impregnation method. The SiC ceramics have been coated with bioactive HA and HA/ZrO2 using effective gas detonation deposition approach (GDD). The surface morphology and cytotoxicity of SiC ceramics as well as phase composition and crystallinity of deposited coatings were analyzed. It has been shown that the porosity and pore size of SiC ceramics depend on initial wood source. The XRD and FTIR studies revealed the preservation of crystal structure and phase composition of in the HA coating, while addition of ZrO2 to the initial HA powder resulted in significant decomposition of the final HA/ZrO2 coating and formation of other calcium phosphate phases. In turn, NIH 3T3 cells cultured in medium exposed to coated and uncoated SiC ceramics showed high re-cultivation efficiency as well as metabolic activity. The recultivation efficiency of cells was the highest for HA-coated ceramics, whereas HA/ZrO2 coating improved the recultivation efficiency of cells as compared to uncoated SiC ceramics. The GDD method allowed generating homogeneous HA coatings with no change in calcium to phosphorus ratio. In summary, porous and cytocompatible bio-SiC ceramics with bioactive coatings show a great promise in construction of light, robust, inexpensive and patient-specific bone implants for clinical application.

  14. Novel intramedullary-fixation technique for long bone fragility fractures using bioresorbable materials.

    Directory of Open Access Journals (Sweden)

    Takanobu Nishizuka

    Full Text Available Almost all of the currently available fracture fixation devices for metaphyseal fragility fractures are made of hard metals, which carry a high risk of implant-related complications such as implant cutout in severely osteoporotic patients. We developed a novel fracture fixation technique (intramedullary-fixation with biodegradable materials; IM-BM for severely weakened long bones using three different non-metallic biomaterials, a poly(l-lactide (PLLA woven tube, a nonwoven polyhydroxyalkanoates (PHA fiber mat, and an injectable calcium phosphate cement (CPC. The purpose of this work was to evaluate the feasibility of IM-BM with mechanical testing as well as with an animal experiment. To perform mechanical testing, we fixed two longitudinal acrylic pipes with four different methods, and used them for a three-point bending test (N = 5. The three-point bending test revealed that the average fracture energy for the IM-BM group (PLLA + CPC + PHA was 3 times greater than that of PLLA + CPC group, and 60 to 200 times greater than that of CPC + PHA group and CPC group. Using an osteoporotic rabbit distal femur incomplete fracture model, sixteen rabbits were randomly allocated into four experimental groups (IM-BM group, PLLA + CPC group, CPC group, Kirschner wire (K-wire group. No rabbit in the IM-BM group suffered fracture displacement even under full weight bearing. In contrast, two rabbits in the PLLA + CPC group, three rabbits in the CPC group, and three rabbits in the K-wire group suffered fracture displacement within the first postoperative week. The present work demonstrated that IM-BM was strong enough to reinforce and stabilize incomplete fractures with both mechanical testing and an animal experiment even in the distal thigh, where bone is exposed to the highest bending and torsional stresses in the body. IM-BM can be one treatment option for those with severe osteoporosis.

  15. Development of Magnesium and Siloxane-containing Vaterite and its Composite Materials for Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Shinya eYamada

    2015-12-01

    Full Text Available Development of novel biomaterials with Mg2+, Ca2+ and silicate ions releasability for bone regeneration is now in progress. Several inorganic ions have been reported to stimulate bone-forming cells. We featured Ca2+, silicate and especially Mg2+ ions as growth factors for osteoblasts. Various biomaterials, such as ceramic powders and organic-inorganic composites, releasing the ions have been developed and investigated in their cytocompatibilities in our previous work. Through the investigation, providing the three ions was found to be effective to activate osteogenic cells. Mg and siloxane-containing vaterite (MgSiV was prepared by a carbonation process as an inorganic particles, which can provide simultaneously releasing ability of Ca2+, silicate and Mg2+ ions to biodegradable polymers. Poly(L-lactic acid (PLLA- and bioactive PLLA-based composites containing vaterite coatings were discussed on their degradability and cytocompatibility using a metallic Mg substrate as Mg2+ ion source. PLLA/SiV composite film, which has a releasability of silicate ions besides Ca2+ ion, was coated on a pure Mg substrate to be compared with the PLLA/V coating. The degradability and releasability of inorganic ions were morphologically and quantitatively monitored in a cell culture medium. The bonding strength between the coatings and Mg substrates was one of the key factors to control Mg2+ ion release from the substrates. The cell culture tests were conducted using mouse osteoblast-like cells (MC3T3-E1 cells; cellular morphology, proliferation and differentiation on the materials were evaluated. The PLLA/V and PLLA/SiV coatings on Mg substrates were found to enhance the proliferation; especially the PLLA/SiV coating possessed a higher ability of inducing the osteogenic differentiation of the cells.

  16. Novel naturally crosslinked electrospun nanofibrous chitosan mats for guided bone regeneration membranes: material characterization and cytocompatibility.

    Science.gov (United States)

    Norowski, Peter A; Fujiwara, Tomoko; Clem, William C; Adatrow, Pradeep C; Eckstein, Eugene C; Haggard, Warren O; Bumgardner, Joel D

    2015-05-01

    Guided bone regeneration (GBR) barrier membranes are used to prevent soft tissue infiltration into the graft space during dental procedures that involve bone grafting. Chitosan materials have shown promise as GBR barrier membranes, due to their biocompatibility and predictable biodegradability, but degradation rates may still be too high for clinical applications. In this study, chitosan GBR membranes were electrospun using chitosan (70% deacetylated, 312 kDa, 5.5 w/v%), with or without the addition of 5 or 10 mm genipin, a natural crosslinking agent, in order to extend the degradation to meet the clinical target time frame of 4-6 months. Membranes were evaluated for fibre diameter, tensile strength, biodegradation rate, bond structure and cytocompatibility. Genipin addition, at 5 or 10 mm, resulted in median fibre diameters 184, 144 and 154 nm for uncrosslinked, 5 mm and 10 mm crosslinked, respectively. Crosslinking, examined by Fourier transform infrared spectroscopy, showed a decrease in N-H stretch as genipin levels were increased. Genipin-crosslinked mats exhibited only 22% degradation based on mass loss, as compared to 34% for uncrosslinked mats at 16 weeks in vitro. The ultimate tensile strength of the mats was increased by 165% to 32 MPa with 10 mm crosslinking as compared to the uncrosslinked mats. Finally, genipin-crosslinked mats supported the proliferation of SAOS-2 cells in a 5 day growth study, similar to uncrosslinked mats. These results suggest that electrospun chitosan mats may benefit from genipin crosslinking and have the potential to meet clinical degradation time frames for GBR applications.

  17. Microscale Material Properties of Bone and the Mineralized Tissues of the Intervertebral Disc-Vertebral Body Interface

    Science.gov (United States)

    Paietta, Rachel C.

    The objective of this dissertation is to understand the influences of material structure on the properties, function and failure of biological connective tissues. Biological interfaces are becoming an increasingly studied system within mechanics and tissue engineering as a model for attaching dissimilar materials. The elastic modulus of bone (≈ 20 GPa) and cartilage (≈ 0.1-1 MPa) differ over orders of magnitude, which should intuitively create high stress concentrations and failure at the interface. Yet, these natural interface systems rarely fail in vivo, and the mechanism by which loads are transferred between tissues has not yet been established. Tissue quality is one major contributor to the mechanical behavior of bone and cartilage, and is defined by properties such as collagen orientation, mineral volume fraction, porosity and tissue geometry. These properties have yet to be established at the bone-cartilage interface in the spine, and the lack of quantitative data on material microstructure and behavior limits treatments and tissue engineering construct design. In this dissertation, second harmonic generation imaging, quantitative backscattered scanning electron imaging and nanoindentation are combined to characterize micrometer scale tissue quality and modulus in both bone and calcified cartilage. These techniques are utilized to: 1) determine the hierarchical micrometer to millimeter scale properties of lamellar bone, 2) quantify changes throughout development and aging at the human intervertebral disc-vertebral body junction, and 3) explore compressive fractures at this interface. This work is the first to provide quantitative data on the mineral volume fraction, collagen orientation and modulus from the same, undecalcified sections of tissue to corroborate tissue structure and mineralization and describe quantitative parameters of the interface. The principal findings from this work indicate that the underlying matrix, or collagen, organization in

  18. Evaluation of bone regenerative capacity in rats claverial bone defect using platelet rich fibrin with and without beta tri calcium phosphate bone graft material

    Directory of Open Access Journals (Sweden)

    Walid Ahmed Abdullah

    2016-07-01

    Conclusion: The addition of β-TCP to PRF significantly improved bone regeneration in the first 2 weeks after surgery. Although the differences between results with and without the addition of β-TCP to PRF were statistically insignificant from weeks 3 to 6, it was nevertheless apparent that the group receiving the combination showed better results. We suggest a synergistic mechanism for this effect.

  19. Alterations in osteoclast function and phenotype induced by different inhibitors of bone resorption--implications for osteoclast quality

    DEFF Research Database (Denmark)

    Neutzsky-Wulff, Anita V; Sørensen, Mette Guldmann; Kocijancic, Dino;

    2010-01-01

    Normal osteoclasts resorb bone by secretion of acid and proteases. Recent studies of patients with loss of function mutations affecting either of these processes have indicated a divergence in osteoclastic phenotypes. These difference in osteoclast phenotypes may directly or indirectly have secon...

  20. Compound soft regenerated skull material for repairing dog skull defects using bone morphogenetic protein as an inductor and nanohydroxyapatite as a scaffold

    Institute of Scientific and Technical Information of China (English)

    Zhidong Shi; Mingwang Liu; Zhongzong Qin; Qinmei Wang; Ying Guo; Haiyong He; Zhonghe Yu

    2008-01-01

    BACKGROUND: In previous studies of skull defects and regeneration, bone morphogenetic protein as an inductor and nanohydroxyapatite as a scaffold have been cocultured with osteoblasts.OBJECTIVE: To verify the characteristics of the new skull regenerated material after compound soft regenerated skull material implantatiom.DESIGN, TIME AND SETTING: The self-control and inter-group control animal experiment was perfurmed at the Sun Yat-sen University, China from February to July 2007.MATERIALS: Twenty-tour healthy adult dogs of both genders weighing 15-20 kg were used in this study. Nanohydroxyapatite as a scaffold was cocultured with osteoblasts. Using demineralized canine bone matrix as a carrier, recombinant human bone morphogenetic protein-2 was employed to prepare compound soft regenerated skull material. Self-designed compound soft regenerated skull material was implanted in models of skull defects.METHODS: Animals were randomly assigned into two groups, Group A (n = 16) and Group B (n = 8).Bilateral 2.5-cm-diameter full-thickness parietal skull defects were made in all animals. In Group A, the right side was reconstructed with calcium alginate gel, osteoblasts, and nanomcter bone meal composite;the left side was reconstructed with calcium alginate gel, osteoblasts, nanometer bone meal and recombinant human bone morphogenetic protein-2 composite. In Group B, the right side was kept as a simple skull detect, and the left side was reconstructed with calcium alginate gel, osteoblasts, nanometer bone meal and recombinant human bone morphogenetic protein-2 composite.MAIN OUTCOME MEASURES: Bone regeneration and histopathological changes at the site of the skull defect were observed with an optical microscope and a scanning electron microscope after surgery.The ability to form bone was measured by alizarin red S staining. In vitro cultured osteoblasts were observed for morphology.RESULTS: One month following surgery, newly formed bone trabeculae mostly covered the

  1. Effects of deleting cannabinoid receptor-2 on mechanical and material properties of cortical and trabecular bone

    Directory of Open Access Journals (Sweden)

    Aysha B. Khalid

    2015-12-01

    Full Text Available Cnr2 is one of two cannabinoid receptors known to regulate bone metabolism. Here, we compared the whole bone properties of femora and tibiae from three-month-old Cnr2−/- mice with wild-type controls using a C57BL/6 background. Bending stiffness was measured by three-point bending. The elastic modulus, density and mineral content were measured using ultrasound, Archimedes’ principle and ashing. Micro-CT was used to measure the second moment of area, inner and outer perimeters of the cortical shaft and trabecular parameters. Deleting Cnr2 increased the bending stiffness by increasing the second moment of area. Bone from affected male mice had a greater modulus than controls, although no difference was observed in females. The fractional volume of trabecular bone was greater in Cnr2−/- females than controls, while no difference was seen in males. These data indicate that inactivating Cnr2 increases the amount of cortical bone in both males and females at 3 months of age, but the effect on trabecular bone is different in the two sexes. These findings extend previous studies looking only at trabecular bone and provide further support for the possible use of Cnr2 antagonists for improving bone properties that may be of value in the treatment of bone disorders.

  2. Histomorphometric analysis of newly formed bone after bilateral maxillary sinus augmentation using two different osteoconductive materials and internal collagen membrane.

    Science.gov (United States)

    Kolerman, Roni; Samorodnitzky-Naveh, Gili R; Barnea, Eitan; Tal, Haim

    2012-02-01

    Deproteinized bovine bone mineral (DBBM) and human freeze-dried bone allograft (FDBA) were compared in five patients undergoing bilateral maxillary sinus floor augmentation using DBBM on one side and FDBA on the contralateral side. After 9 months, core biopsy specimens were harvested. Mean newly formed bone values were 31.8% and 27.2% at FDBA and DBBM sites, respectively (P = .451); mean residual graft particle values were 21.5% and 24.2%, respectively (P = .619); and mean connective tissue values were 46.7% and 48.6%, respectively (P = .566). Within the limits of the present study, it is suggested that both graft materials are equally suitable for sinus augmentation.

  3. Moderate exercise during pregnancy in Wistar rats alters bone and body composition of the adult offspring in a sex-dependent manner.

    Directory of Open Access Journals (Sweden)

    Brielle V Rosa

    Full Text Available Exercise during pregnancy may have long-lasting effects on offspring health. Musculoskeletal growth and development, metabolism, and later-life disease risk can all be impacted by the maternal environment during pregnancy. The skeleton influences glucose handling through the actions of the bone-derived hormone osteocalcin. The purpose of this study was to test the effects of moderate maternal exercise during pregnancy on the bone and body composition of the offspring in adult life, and to investigate the role of osteocalcin in these effects. Groups of pregnant Wistar rats either performed bipedal standing exercise to obtain food/water throughout gestation but not lactation, or were fed conventionally. Litters were reduced to 8/dam and pups were raised to maturity under control conditions. Whole body dual-energy x-ray absorptiometry, and ex vivo peripheral quantitative computed tomography scans of the right tibia were performed. At study termination blood and tissue samples were collected. Serum concentrations of fully and undercarboxylated osteocalcin were measured, and the relative expression levels of osteocalcin, insulin receptor, Forkhead box transcription factor O1, and osteotesticular protein tyrosine phosphatase mRNA were quantified. Body mass did not differ between the offspring of exercised and control dams, but the male offspring of exercised dams had a greater % fat and lower % lean than controls (p=0.001 and p=0.0008, respectively. At the mid-tibial diaphysis, offspring of exercised dams had a lower volumetric bone mineral density than controls (p=0.01 and in the male offspring of exercised dams the bone: muscle relationship was fundamentally altered. Serum concentrations of undercarboxylated osteocalcin were significantly greater in the male offspring of exercised dams than in controls (p=0.02; however, the relative expression of the measured genes did not differ between groups. These results suggest that moderate exercise during

  4. Moderate exercise during pregnancy in Wistar rats alters bone and body composition of the adult offspring in a sex-dependent manner.

    Science.gov (United States)

    Rosa, Brielle V; Blair, Hugh T; Vickers, Mark H; Dittmer, Keren E; Morel, Patrick C H; Knight, Cameron G; Firth, Elwyn C

    2013-01-01

    Exercise during pregnancy may have long-lasting effects on offspring health. Musculoskeletal growth and development, metabolism, and later-life disease risk can all be impacted by the maternal environment during pregnancy. The skeleton influences glucose handling through the actions of the bone-derived hormone osteocalcin. The purpose of this study was to test the effects of moderate maternal exercise during pregnancy on the bone and body composition of the offspring in adult life, and to investigate the role of osteocalcin in these effects. Groups of pregnant Wistar rats either performed bipedal standing exercise to obtain food/water throughout gestation but not lactation, or were fed conventionally. Litters were reduced to 8/dam and pups were raised to maturity under control conditions. Whole body dual-energy x-ray absorptiometry, and ex vivo peripheral quantitative computed tomography scans of the right tibia were performed. At study termination blood and tissue samples were collected. Serum concentrations of fully and undercarboxylated osteocalcin were measured, and the relative expression levels of osteocalcin, insulin receptor, Forkhead box transcription factor O1, and osteotesticular protein tyrosine phosphatase mRNA were quantified. Body mass did not differ between the offspring of exercised and control dams, but the male offspring of exercised dams had a greater % fat and lower % lean than controls (p=0.001 and p=0.0008, respectively). At the mid-tibial diaphysis, offspring of exercised dams had a lower volumetric bone mineral density than controls (p=0.01) and in the male offspring of exercised dams the bone: muscle relationship was fundamentally altered. Serum concentrations of undercarboxylated osteocalcin were significantly greater in the male offspring of exercised dams than in controls (p=0.02); however, the relative expression of the measured genes did not differ between groups. These results suggest that moderate exercise during pregnancy can

  5. Alterations of bone density, microstructure, and strength of the distal radius in male patients with rheumatoid arthritis: a case-control study with HR-pQCT.

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    Zhu, Tracy Y; Griffith, James F; Qin, Ling; Hung, Vivian W; Fong, Tsz-Ning; Au, Sze-Ki; Li, Martin; Lam, Yvonne Yi-On; Wong, Chun-Kwok; Kwok, Anthony W; Leung, Ping-Chung; Li, Edmund K; Tam, Lai-Shan

    2014-09-01

    In this cross-sectional study, we investigated volumetric bone mineral density (vBMD), bone microstructure, and biomechanical competence of the distal radius in male patients with rheumatoid arthritis (RA). The study cohort comprised 50 male RA patients of average age of 61.1 years and 50 age-matched healthy males. Areal BMD (aBMD) of the hip, lumbar spine, and distal radius was measured by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) of the distal radius provided measures of cortical and trabecular vBMD, microstructure, and biomechanical indices. aBMD of the hip but not the lumbar spine or ultradistal radius was significantly lower in RA patients than controls after adjustment for body weight. Total, cortical, and trabecular vBMD at the distal radius were, on average, -3.9% to -23.2% significantly lower in RA patients, and these differences were not affected by adjustment for body weight, testosterone level, or aBMD at the ultradistal radius. Trabecular microstructure indices were, on average, -8.1% (trabecular number) to 28.7% (trabecular network inhomogeneity) significantly inferior, whereas cortical pore volume and cortical porosity index were, on average, 80.3% and 63.9%, respectively, significantly higher in RA patients. RA patients also had significantly lower whole-bone stiffness, modulus, and failure load, with lower and more unevenly distributed cortical and trabecular stress. Density and microstructure indices significantly correlated with disease activity, severity, and levels of pro-inflammatory cytokines (interleukin [IL] 12p70, tumor necrosis factor, IL-6 and IL-1β). Ten RA patients had focal periosteal bone apposition most prominent at the ulnovolar aspect of the distal radius. These patients had shorter disease duration and significantly higher cortical porosity. In conclusion, HR-pQCT reveals significant alterations of bone density, microstructure, and strength of the distal radius in

  6. 1,25(OH2D3 alters growth plate maturation and bone architecture in young rats with normal renal function.

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    Anna Idelevich

    Full Text Available Whereas detrimental effects of vitamin D deficiency are known over century, the effects of vitamin D receptor activation by 1,25(OH(2D(3, the principal hormonal form of vitamin D, on the growing bone and its growth plate are less clear. Currently, 1,25(OH(2D(3 is used in pediatric patients with chronic kidney disease and mineral and bone disorder (CKD-MBD and is strongly associated with growth retardation. Here, we investigate the effect of 1,25(OH(2D(3 treatment on bone development in normal young rats, unrelated to renal insufficiency. Young rats received daily i.p. injections of 1 µg/kg 1,25(OH(2D(3 for one week, or intermittent 3 µg/kg 1,25(OH(2D(3 for one month. Histological analysis revealed narrower tibial growth plates, predominantly in the hypertrophic zone of 1,25(OH(2D(3-treated animals in both experimental protocols. This phenotype was supported by narrower distribution of aggrecan, collagens II and X mRNA, shown by in situ hybridization. Concomitant with altered chondrocyte maturation, 1,25(OH(2D(3 increased chondrocyte proliferation and apoptosis in terminal hypertrophic cells. In vitro treatment of the chondrocytic cell line ATDC5 with 1,25(OH(2D(3 lowered differentiation and increased proliferation dose and time-dependently. Micro-CT analysis of femurs from 1-week 1,25(OH(2D(3-treated group revealed reduced cortical thickness, elevated cortical porosity, and higher trabecular number and thickness. 1-month administration resulted in a similar cortical phenotype but without effect on trabecular bone. Evaluation of fluorochrome binding with confocal microscopy revealed inhibiting effects of 1,25(OH(2D(3 on intracortical bone formation. This study shows negative effects of 1,25(OH(2D(3 on growth plate and bone which may contribute to the exacerbation of MBD in the CKD pediatric patients.

  7. 1,25(OH)2D3 alters growth plate maturation and bone architecture in young rats with normal renal function.

    Science.gov (United States)

    Idelevich, Anna; Kerschnitzki, Michael; Shahar, Ron; Monsonego-Ornan, Efrat

    2011-01-01

    Whereas detrimental effects of vitamin D deficiency are known over century, the effects of vitamin D receptor activation by 1,25(OH)(2)D(3), the principal hormonal form of vitamin D, on the growing bone and its growth plate are less clear. Currently, 1,25(OH)(2)D(3) is used in pediatric patients with chronic kidney disease and mineral and bone disorder (CKD-MBD) and is strongly associated with growth retardation. Here, we investigate the effect of 1,25(OH)(2)D(3) treatment on bone development in normal young rats, unrelated to renal insufficiency. Young rats received daily i.p. injections of 1 µg/kg 1,25(OH)(2)D(3) for one week, or intermittent 3 µg/kg 1,25(OH)(2)D(3) for one month. Histological analysis revealed narrower tibial growth plates, predominantly in the hypertrophic zone of 1,25(OH)(2)D(3)-treated animals in both experimental protocols. This phenotype was supported by narrower distribution of aggrecan, collagens II and X mRNA, shown by in situ hybridization. Concomitant with altered chondrocyte maturation, 1,25(OH)(2)D(3) increased chondrocyte proliferation and apoptosis in terminal hypertrophic cells. In vitro treatment of the chondrocytic cell line ATDC5 with 1,25(OH)(2)D(3) lowered differentiation and increased proliferation dose and time-dependently. Micro-CT analysis of femurs from 1-week 1,25(OH)(2)D(3)-treated group revealed reduced cortical thickness, elevated cortical porosity, and higher trabecular number and thickness. 1-month administration resulted in a similar cortical phenotype but without effect on trabecular bone. Evaluation of fluorochrome binding with confocal microscopy revealed inhibiting effects of 1,25(OH)(2)D(3) on intracortical bone formation. This study shows negative effects of 1,25(OH)(2)D(3) on growth plate and bone which may contribute to the exacerbation of MBD in the CKD pediatric patients.

  8. Osteogenesis and cytotoxicity of a new Carbon Fiber/Flax/Epoxy composite material for bone fracture plate applications.

    Science.gov (United States)

    Bagheri, Zahra S; Giles, Erica; El Sawi, Ihab; Amleh, Asma; Schemitsch, Emil H; Zdero, Radovan; Bougherara, Habiba

    2015-01-01

    This study is part of an ongoing program to develop a new CF/Flax/Epoxy bone fracture plate to be used in orthopedic trauma applications. The purpose was to determine this new plate's in-vitro effects on the level of bone formation genes, as well as cell viability in comparison with a medical grade metal (i.e. stainless steel) commonly employed for fabrication of bone plates (positive control). Cytotoxicity and osteogenesis induced by wear debris of the material were assessed using Methyl Tetrazolium (MTT) assay and reverse transcription polymerase chain reaction (RT-PCR) for 3 osteogenesis specific gene markers, including bone morphogenetic proteins (BMP2), runt-related transcription factor 2 (Runx2) and Osterix. Moreover, the Flax/Epoxy and CF/Epoxy composites were examined separately for their wettability properties by water absorption and contact angle (CA) tests using the sessile drop technique. The MTT results for indirect and direct assays indicated that the CF/Flax/Epoxy composite material showed comparable cell viability with no cytotoxicity at all incubation times to that of the metal group (p≥0.05). Osteogenesis test results showed that the expression level of Runx2 marker induced by CF/Flax/Epoxy were significantly higher than those induced by metal after 48 h (p=0.57). Also, the Flax/Epoxy composite revealed a hydrophilic character (CA=68.07°±2.05°) and absorbed more water up to 17.2% compared to CF/Epoxy, which reached 1.25% due to its hydrophobic character (CA=93.22°±1.95°) (p<0.001). Therefore, the new CF/Flax/Epoxy may be a potential candidate for medical applications as a bone fracture plate, as it showed similar cell viability with no negative effect on gene expression levels responsible for bone formation compared to medical grade stainless steel.

  9. Genetics of the Steller's Sea Cow (Hydrodamalis gigas): A Study of Ancient Bone Material

    Science.gov (United States)

    Crerar, Lorelei D.

    Georg Wilhelm Steller was born 100 years before Darwin in 1709 and he was part of a vast exploration fifty years before Lewis and Clark explored America. Steller was important to the study of marine mammals because he was the only naturalist to see and describe the great northern sea cow ( Hydrodamalis gigas). Knowledge of an extinct population can be used to aid the conservation of a current population. Extraction of DNA from this extinct animal was performed in order to determine the population structure of the Steller's sea cow. A test was also developed that can definitively state whether or not a random bone sample came from H. gigas. This test could be used by the Fish and Wildlife Service (FWS) and the National Oceanic and Atmospheric Administration (NOAA) to examine material distributed in the North Pacific to determine whether samples are legally traded extinct Steller's sea cow or illegally traded extant marine mammal species protected under the Marine Mammal Protection Act (MMPA).

  10. Perlecan/Hspg2 deficiency alters the pericellular space of the lacunocanalicular system surrounding osteocytic processes in cortical bone.

    Science.gov (United States)

    Thompson, William R; Modla, Shannon; Grindel, Brian J; Czymmek, Kirk J; Kirn-Safran, Catherine B; Wang, Liyun; Duncan, Randall L; Farach-Carson, Mary C

    2011-03-01

    Osteocytes project long, slender processes throughout the mineralized matrix of bone, where they connect and communicate with effector cells. The interconnected cellular projections form the functional lacunocanalicular system, allowing fluid to pass for cell-to-cell communication and nutrient and waste exchange. Prevention of mineralization in the pericellular space of the lacunocanalicular pericellular space is crucial for uninhibited interstitial fluid movement. Factors contributing to the ability of the pericellular space of the lacunocanalicular system to remain open and unmineralized are unclear. Immunofluorescence and immunogold localization by transmission electron microscopy demonstrated perlecan/Hspg2 signal localized to the osteocyte lacunocanalicular system of cortical bone, and this proteoglycan was found in the pericellular space of the lacunocanalicular system. In this study we examined osteocyte lacunocanalicular morphology in mice deficient in the large heparan sulfate proteoglycan perlecan/Hspg2 in this tissue. Ultrastructural measurements with electron microscopy of perlecan/Hspg2-deficient mice demonstrated diminished osteocyte canalicular pericellular area, resulting from a reduction in the total canalicular area. Additionally, perlecan/Hspg2-deficient mice showed decreased canalicular density and a reduced number of transverse tethering elements per canaliculus. These data indicated that perlecan/Hspg2 contributed to the integrity of the osteocyte lacunocanalicular system by maintaining the size of the pericellular space, an essential task to promote uninhibited interstitial fluid movement in this mechanosensitive environment. This work thus identified a new barrier function for perlecan/Hspg2 in murine cortical bone.

  11. RESULTS OF THE FOSFOMYCIN APPLICATION FOR THE IMPREGNATION OF BONE REPLACEMENT MATERIALS IN THE TREATMENT OF CHRONIC OSTEOMYELITIS

    Directory of Open Access Journals (Sweden)

    V. A. Konev

    2016-01-01

    Full Text Available Aim – to evaluate in the experimental study in vitro the duration of antimicrobial activity of fosfomycin-impregnated bone cement and to study the dynamics of radiological and morphological changes depending on the local antibiotic therapy in two-stage treatment of chronic osteomyelitis in rabbits.Materials and methods. Duration of antimicrobial activity of bone cement (depuy cmw1 gentamicin with fosfomycin in vitro was studied in comparison to cements with vancomycin and controls without additional antibiotics. Presence of the lysis zone of bacterial cultures was evaluated (Staphylococcus aureus ATCC6538 and ATCC33591, Klebsiella pneumoniae ATCC33495 and Escherichia coli ATCC25922 after application of 10 μl of the solution, collected from the cement samples after incubation for 24 hours. For the in vivo experiment, Chinchilla rabbits (n = 20 with local osteomyelitis of the tibia underwent two-stage treatment where substitution of the bone defect at stage I was performed with PMMA and stage II – with the bioresorbable material based on hydroxyapatite and triclacium phosphate (ReproBone. In an experience group (n = 10 before setting osteoreplacement materials with fosfomycin (group FOSFO, and by control (n = 10 – vancomycin (group VANCO. X-ray imaging was performed on the 1st and 21st day after installation of the cement spacer, and 45th day after substitution of the spacer with the bioresorbable material. Microbiological analysis of the samples was performed intraoperatively and on the 7th, 14th day after each stage. Histological study was conducted in both groups on the 14th, 21th day after stage I and 45th day after stage II of the treatment.Results. Maximal duration of antimicrobial activity in vitro was observed in samples of PMMA with fosfomycin whereas minimal – in control samples of gentamicin-based bone cement. Relief of the infection was attained in all animals while application of fosfomycin resulted in a more

  12. The impact of bone and suture material properties on mandibular function in Alligator mississippiensis: testing theoretical phenotypes with finite element analysis

    Science.gov (United States)

    Reed, David A; Porro, Laura B; Iriarte-Diaz, Jose; Lemberg, Justin B; Holliday, Casey M; Anapol, Fred; Ross, Callum F

    2011-01-01

    Abstract The functional effects of bone and suture stiffness were considered here using finite element models representing three different theoretical phenotypes of an Alligator mississippiensis mandible. The models were loaded using force estimates derived from muscle architecture in dissected specimens, constrained at the 18th and 19th teeth in the upper jaw and 19th tooth of the lower jaw, as well as at the quadrate-articular joint. Stiffness was varied systematically in each theoretical phenotype. The three theoretical phenotypes included: (i) linear elastic isotropic bone of varying stiffness and no sutures; (ii) linear elastic orthotropic bone of varying stiffness with no sutures; and (iii) linear elastic isotropic bone of a constant stiffness with varying suture stiffness. Variation in the isotropic material properties of bone primarily resulted in changes in the magnitude of principal strain. By comparison, variation in the orthotropic material properties of bone and isotropic material properties of sutures resulted in: a greater number of bricks becoming either more compressive or more tensile, changing between being either dominantly compressive or tensile, and having larger changes in the orientation of maximum principal strain. These data indicate that variation in these model properties resulted in changes to the strain regime of the model, highlighting the importance of using biologically verified material properties when modeling vertebrate bones. When bones were compared within each set, the response of each to changing material properties varied. In two of the 12 bones in the mandible, varied material properties within sutures resulted in a decrease in the magnitude of principal strain in bricks adjacent to the bone/suture interface and decreases in stored elastic energy. The varied response of the mandibular bones to changes in suture stiffness highlights the importance of defining the appropriate functional unit when addressing relationships of

  13. Orchidectomy-induced alterations in volumetric bone density, cortical porosity and strength of femur are attenuated by dietary conjugated linoleic acid in aged guinea pigs.

    Science.gov (United States)

    DeGuire, Jason R; Mak, Ivy L; Lavery, Paula; Agellon, Sherry; Wykes, Linda J; Weiler, Hope A

    2015-04-01

    Age-related osteoporosis and sarcopenia are ascribed in part to reductions in anabolic hormones. Dietary conjugated linoleic acid (CLA) improves lean and bone mass, but its impact during androgen deficiency is not known. This study tested if CLA would attenuate the effects of orchidectomy (ORX)-induced losses of bone and lean tissue. Male guinea pigs (n=40; 70-72 weeks), were randomized into four groups: (1) SHAM+Control diet, (2) SHAM+CLA diet, (3) ORX+Control diet, (4) ORX+CLA diet. Baseline blood sampling and dual-energy X-ray absorptiometry (DXA) scans were conducted, followed by surgery 4 days later with the test diets started 7 days after baseline sampling. Serial blood sampling and DXA scans were repeated 2, 4, 8 and 16 weeks on the test diets. Body composition and areal BMD (aBMD) of whole body, lumbar spine, femur and tibia were measured using DXA. At week 16, muscle protein fractional synthesis rate (FSR), volumetric BMD (vBMD), microarchitecture and bone strength were assessed. Body weight declined after SHAM and ORX surgery, with slower recovery in the ORX group. Dietary CLA did not affect weight or lean mass, but attenuated gains in fat mass. Lean mass was stable in SHAM and reduced in ORX by 2 weeks with whole body and femur bone mineral content (BMC) reduced by 4 weeks; CLA did not alter BMC. By week 16 ORX groups had lower free testosterone and myofibrillar FSR, yet higher cortisol, osteocalcin and ionized calcium with no alterations due to CLA. ORX+Control had higher prostaglandin E2 (PGE2) and total alkaline phosphatase compared to SHAM+Control whereas ORX+CLA were not different from SHAM groups. Femur metaphyseal vBMD was reduced in ORX+CTRL with the reduction attenuated by CLA. Femur cortical thickness (Ct.Th.) and biomechanical strength were reduced and cortical porosity (Ct.Po.) elevated by ORX and attenuated by CLA. This androgen deficient model with a sarcopenic-osteoporotic phenotype similar to aging men responded to dietary CLA with

  14. Alteration in serum and bone component findings induced in streptozotocin-diabetic rats is restored by zinc acexamate.

    Science.gov (United States)

    Uchiyama, Satoshi; Yamaguchi, Masayoshi

    2003-12-01

    The effect of zinc acexamate in streptozotocin (STZ)-induced diabetic rats was investigated. Rats received a single subcutaneous administration of STZ (6.0 mg/100 g body weight), and the animals were orally administered once daily for 14 days with zinc acexamate (2.5, 5 or 10 mg/100 g body weight). The administration of STZ caused a significant increase in serum glucose, triglyceride and calcium levels and a significant decrease in body weight, serum zinc and inorganic phosphorus levels, indicating diabetic condition. Moreover, calcium content, alkaline phosphatase activity and deoxyribonucleic acid (DNA) content in the femoral-diaphyseal and -metaphyseal tissues were significantly reduced in STZ-diabetic rats. The change in these serum and bone components of STZ-diabetic rats was significantly restored by the oral administration of zinc acexamate (2.5, 5 or 10 mg Zn/100 g body weight). The restoration of bone components was not seen by the oral administration of zinc sulfate (2.5 mg Zn/100 g) for 14 days. Moreover, when the femoral-diaphyseal and -metaphyseal tissues obtained at 14 days after STZ administration were cultured for 48 h in a medium containing either vehicle or zinc acexamate (10(-5) M), the femoral calcium content and alkaline phosphatase activity were significantly increased in vitro. The effect of zinc acexamate was completely abolished in the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis. The present study demonstrates that the oral administration of zinc acexamate has a preventive effect on STZ-induced diabetic condition in rats, and that it can restorate bone loss of STZ-induced diabetes in vivo.

  15. The role of angiogenesis in implant dentistry part II: The effect of bone-grafting and barrier membrane materials on angiogenesis

    Science.gov (United States)

    Asatourian, Armen; Garcia-Godoy, Franklin; Sheibani, Nader

    2016-01-01

    Background In implant dentistry, bone substitute materials and barrier membranes are used in different treatments including guided bone regeneration (GBR), socket preservation, alveolar ridge augmentation, maxillary sinus elevation, and filling bony defects around the inserted dental implant. One of the most important factors in prognosis of treatments using these materials is the growth of new blood vessels in applied areas. Present review was performed to evaluate the effect of the bone-grafting and barrier membrane materials on angiogenesis events. Material and Methods An electronic search was performed in PubMed, MEDLINE, and EMBASE databases via OVID using the keywords mentioned in the PubMed and MeSH headings regarding the role of angiogenesis in implant dentistry from January 2000-April 2014. Results Of the 5,622 articles identified in our initial search results, only 33 met the inclusion criteria set for this review. Among bone substitute materials the autogenous bone-grafts, and among the barrier membranes the collagenous membranes, had the highest angiogenic potentials. Other bone-grafting materials or membranes were mostly used with pro-angiogenic factors to enhance their angiogenic properties. Conclusions Angiogenesis is one of the key factors, which plays a critical role in success rate of GBR technique and is seriously considered in manufacturing bone-grafting and barrier membrane materials. However, there is still lack of clinical and in-vivo studies addressing the effect of angiogenesis in treatments using bone-grafting and barrier membrane materials. Key words:Angiogenesis, bone-grafting materials, GBR, ridge augmentation, sinus elevation, socket preservation. PMID:27031074

  16. [Combined treatment of long tubular bone fractures and false joints using the bioplastic material collapan (Russia)].

    Science.gov (United States)

    Kesian, G A; Berchenko, G N; Urazgil'deev, R Z; Arsen'ev, I G; Mikelaishvili, D S; Karapetian, G S

    2008-01-01

    This experimental morphological study on 32 dogs was designed to evaluate the efficiency of hydroxyapatite containing preparation collapan used to promote healing of segmented femur defects. Implantation of collapan was shown to greatly contribute to the formation, maturation and remodelling of bone callus. Combined treatment of 165 patients with comminuted fractures and 148 ones with false joints of long tubular bones using collapan implants proved to efficaciously promote bone consolidation in 99.4% of the total 313 subjects. Collapan activated reparative osteogenesis, reduced the duration of hospitalization, the frequency of inflammatory complications, and the requirement of secondary inpatient care.

  17. Microindentation for in vivo measurement of bone tissue material properties in atypical femoral fracture patients and controls.

    Science.gov (United States)

    Güerri-Fernández, Roberto C; Nogués, Xavier; Quesada Gómez, José M; Torres Del Pliego, Elisa; Puig, Lluís; García-Giralt, Natalia; Yoskovitz, Guy; Mellibovsky, Leonardo; Hansma, Paul K; Díez-Pérez, Adolfo

    2013-01-01

    Atypical femoral fractures (AFF) associated with long-term bisphosphonates (LTB) are a growing concern. Their etiology is unknown, but bone material properties might be deteriorated. In an AFF series, we analyzed the bone material properties by microindentation. Four groups of patients were included: 6 AFF, 38 typical osteoporotic fractures, 6 LTB, and 20 controls without fracture. Neither typical osteoporotic fractures nor controls have received any antiosteoporotic medication. A general laboratory workup, bone densitometry by dual-energy X-ray absorptiometry (DXA), and microindentation testing at the tibia were done in all patients. Total indentation distance (Total ID), indentation distance increase (IDI), and creep indentation distance (Creep ID) were measured (microns). Age-adjusted analysis of covariance (ANCOVA) was used for comparisons. Controls were significantly younger than fracture groups. Bisphosphonate exposure was on average 5.5 years (range 5 to 12 years) for the AFF and 5.4 years (range 5 to 8 years) for the LTB groups. Total ID (microns) showed better material properties (lower Total ID) for controls 36 (± 6; mean ± SD) than for AFF 46 (± 4) and for typical femoral fractures 47 (± 13), respectively. Patients on LTB showed values between controls and fractures, 38 (± 4), although not significantly different from any of the other three groups. IDI values showed a similar pattern 13 (± 2), 16 (± 6), 19 (± 3), and 18 (± 5). After adjusting by age, significant differences were seen between controls and typical (p Creep ID between groups. Our data suggest that patients with AFF have a deep deterioration in bone material properties at a tissue level similar to that for the osteoporotic fracture group. The LTB group shows levels that are in between controls and both type of fractures, although not statistically different. These results suggest that bisphosphonate therapy probably does not put the majority of patients at risk

  18. Effect of higher frequency components and duration of vibration on bone tissue alterations in the rat-tail model.

    Science.gov (United States)

    Peelukhana, Srikara V; Goenka, Shilpi; Kim, Brian; Kim, Jay; Bhattacharya, Amit; Stringer, Keith F; Banerjee, Rupak K

    2015-01-01

    To formulate more accurate guidelines for musculoskeletal disorders (MSD) linked to Hand-Arm Vibration Syndrome (HAVS), delineation of the response of bone tissue under different frequencies and duration of vibration needs elucidation. Rat-tails were vibrated at 125 Hz (9 rats) and 250 Hz (9 rats), at 49 m/s(2), for 1D (6 rats), 5D (6 rats) and 20D (6 rats); D=days (4 h/d). Rats in the control group (6 rats for the vibration groups; 2 each for 1D, 5D, and 20D) were left in their cages, without being subjected to any vibration. Structural and biochemical damages were quantified using empty lacunae count and nitrotyrosine signal-intensity, respectively. One-way repeated-measure mixed-model ANOVA at pbone, structural damage quantified through empty lacunae count was significant (pbone while the trabecular bone showed significant (pbone tissue are dependent upon higher vibration frequencies of 125 Hz, 250 Hz and the duration of vibration (5D, 20D).

  19. Mineralization Content Alters Osteogenic Responses of Bone Marrow Stromal Cells on Hydroxyapatite/Polycaprolactone Composite Nanofiber Scaffolds

    Directory of Open Access Journals (Sweden)

    Ketul C. Popat

    2012-11-01

    Full Text Available Synthetic tissue scaffolds have a high potential impact for patients experiencing osteogenesis imperfecta. Using electrospinning, tissue scaffolds composed of hydroxyapatite/polycaprolactone (HAp/PCL composite nanofibers were fabricated with two different HAp concentrations—1% and 10% of the solid scaffold weight. After physico-chemical scaffold characterization, rat bone marrow stromal cells were cultured on the composite scaffolds in maintenance medium and then in osteogenic medium. Quantitative PCR, colorimetric assays, immunofluorescent labeling, and electron microscopy measured osteogenic cell responses to the HAp/PCL scaffolds. In maintenance conditions, both Hap/PCL scaffolds and control scaffolds supported cell colonization through seven days with minor differences. In osteogenic conditions, the 10% HAp scaffolds exhibited significantly increased ALP assay levels at week 3, consistent with previous reports. However, qPCR analysis demonstrated an overall decrease in bone matrix-associated genes on Hap/PCL scaffolds. Osteopontin and osteocalcin immunofluorescent microscopy revealed a trend that both mineralized scaffolds had greater amounts of both proteins, though qPCR results indicated the opposite trend for osteopontin. Additionally, type I collagen expression decreased on HAp scaffolds. These results indicate that cells are sensitive to minor changes in mineral content within nanofibers, even at just 1% w/w, and elucidating the sensing mechanism may lead to optimized osteogenic scaffold designs.

  20. 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.

  1. Alteration of hedgehog signaling by chronic exposure to different pesticide formulations and unveiling the regenerative potential of recombinant sonic hedgehog in mouse model of bone marrow aplasia.

    Science.gov (United States)

    Chaklader, Malay; Law, Sujata

    2015-03-01

    Chronic pesticide exposure-induced downregulation of hedgehog signaling and its subsequent degenerative effects on the mammalian hematopoietic system have not been investigated yet. However a number of concurrent studies have pointed out the positive correlation between chronic pesticide exposure induced bone marrow failure and immune suppression. Here, we have given an emphasis on the recapitulation of human marrow aplasia like condition in mice by chronic mixed pesticide exposures and simultaneously unravel the role of individual pesticides in the said event. Unlike the effect of mixed pesticide, individual pesticides differentially alter the hedgehog signaling in the bone marrow primitive hematopoietic compartment (Sca1 + compartment) and stromal compartment. Individually, hexaconazole disrupted hematopoietic as well as stromal hedgehog signaling activation through inhibiting SMO and facilitating PKC δ expression. On contrary, both chlorpyriphos and cypermethrin increased the sequestration and degradation of GLI1 by upregulating SU(FU) and βTrCP, respectively. However, cypermethrin-mediated inhibition of hedgehog signaling has partly shown to be circumvented by non-canonical activation of GLI1. Finally, we have tested the regenerative response of sonic hedgehog and shown that in vitro supplemented recombinant SHH protein augmented clonogenic stromal progenitors (CFU-F) as well as primitive multipotent hematopoietic clones including CFU-GEMM and CFU-GM of mixed pesticide-induced aplastic marrow. It is an indication of the marrow regeneration. Finally, our findings provide a gripping evidence that downregulated hedgehog signaling contribute to pesticide-mediated bone marrow aplasia but it could be recovered by proper supplementation of recombinant SHH along with hematopoietic base cocktail. Furthermore, SU(FU) and GLI1 can be exploited as future theradiagnostic markers for early marrow aplasia diagnosis.

  2. Cryopreservation of Bone Marrow Mononuclear Cells Alters Their Viability and Subpopulation Composition but Not Their Treatment Effects in a Rodent Stroke Model

    Directory of Open Access Journals (Sweden)

    Bing Yang

    2016-01-01

    Full Text Available The systemic administration of autologous bone marrow (BM derived mononuclear cells (MNCs is under investigation as a novel therapeutic modality for the treatment of ischemic stroke. Autologous applications raise the possibility that MNCs could potentially be stored as a banked source. There have been no studies that investigate the effects of cryopreservation of BM-MNCs on their functional abilities in stroke models. In the present study, C57BL/6 mice were subjected to middle cerebral artery occlusion (MCAo for 60 minutes and then divided into two treatment groups: fresh MNCs versus cryopreserved MNCs. BM-MNCs were collected at 22 hours after MCAo and were stored in liquid nitrogen for 12 months in cryopreserved MNCs group. BM-MNCs cellular viability, composition, and phenotype of the various subpopulations of mice BM-MNCs were evaluated by flow cytometry, and the behavioral recovery of stroke animals was tested with freshly harvested MNCs versus cryopreserved MNCs by corner test and ladder rung test. We found that long-term cryopreservation negatively impacts the cellular viability of bone marrow MNCs. Cryopreservation also alters the cellular composition of various subpopulations within the MNCs. However, despite the changes observed in cryopreserved cells, both fresh and frozen MNCs have similar beneficial effect on behavioral and histological outcomes.

  3. Magnesium modification of a calcium phosphate cement alters bone marrow stromal cell behavior via an integrin-mediated mechanism.

    Science.gov (United States)

    Zhang, Jing; Ma, Xiaoyu; Lin, Dan; Shi, Hengsong; Yuan, Yuan; Tang, Wei; Zhou, Huanjun; Guo, Han; Qian, Jiangchao; Liu, Changsheng

    2015-06-01

    The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration.

  4. MSL SAM-like Analyses of Hawaiian Altered Basaltic Materials: Implications for Analyses by the Mars Science Laboratory

    Science.gov (United States)

    McAdam, A.; Eigenbrode, J. L.; Young, K. E.; Bleacher, J. E.; Knudson, C. A.; Rogers, D.; Glotch, T. D.; Sutter, B.; Mahaffy, P. R.; Navarro-Gonzalez, R.; Downs, R. T.

    2015-12-01

    Samples of basaltic materials were collected during several traverses of the Kau Desert on the leeward side of the Kilauea Volcano, Hawaii, conducted by the Remote, In Situ, and Synchrotron Studies for Science and Exploration (RIS4E) team, a node of the Solar System Exploration and Research Virtual Institute (SSERVI) program. Some of these samples had been exposed to circumneutral to slightly acidic alteration conditions from exposure to fog/rain, and acidic fog/rain, while others had been exposed to more acidic conditions due to proximity to fumaroles. The samples consisted of basalts with coatings, sands and soils, and ash, and were collected using organically clean protocols to enable investigation of organic chemistry and organic-mineral associations, in addition to mineralogy. The Mars Science Laboratory (MSL) rover has analyzed basaltic materials inferred to have been altered under conditions ranging from circumneutral to acidic, but several aspects of the Sample Analysis at Mars (SAM) instrument suite results are still being investigated and analyses of relevant terrestrial analogs can play an important role in interpretation of the data. For example, all materials analyzed to date have a significant amorphous component. Comparisons of the mineralogy obtained with the MSL CheMin instrument and volatiles evolved during SAM analyses indicate that, by mass balance, some portion of the volatiles, such as SO2 and H2O, are likely associated with this component. Many of the RIS4E samples also have a significant amorphous component, and field x-ray diffraction (XRD) and x-ray fluorescence (XRF) data indicate differences in the chemistry of this material in samples exposed to different alteration conditions. Preliminary SAM-like analyses indicate that the amorphous materials in some of these samples evolve volatiles such as H2O and SO2 during heating. Here we will discuss these results, and others, obtained through SAM-like analyses of selected samples.

  5. Beneficial use of meat and bone meal combustion residue: "an efficient low cost material to remove lead from aqueous effluent".

    Science.gov (United States)

    Deydier, Eric; Guilet, Richard; Sharrock, Patrick

    2003-07-04

    Meat and bone meal (MBM) combustion residues, a natural apatite-rich substance, was evaluated as a low cost substitute for hydroxyapatite in lead sequestration from water effluents. The thermal behaviour of crude meat and bone meal was followed by TGA and 24% inorganic residue was collected. The resulting ashes were characterised by powder X-ray diffraction (XRD), particle size distribution, specific surface area (BET), and elemental analysis confirming apatite contents, with high level of phosphate (56.3%) and calcium (36.8%). Mechanism and kinetics of lead removal by this bioinorganic material were investigated and compared to mechanisms and kinetics involved with synthetic apatite. Batch metal removal experiments were carried out with 500 and 1500ppm (mg/kg) Pb(2+) solutions. Lead concentration, calcium and pH were monitored. We observed that the mechanism is similar to that occurring for pure apatite, and involved both surface complexation and calcium hydroyapatite (CaHA), Ca(10)(PO(4))(6)(OH)(2), dissolution followed by less soluble Pb(10)(PO(4))(6)(OH)(2) precipitation, as confirmed by XRD analysis of ashes after incubation with lead solution. Our results show that this natural apatite-rich material removes in a few minutes a large quantity of lead (275mg/g capacity) which remains however lower than the theoretical maximum capacity (if calcium were totally substituted by lead). Meat and bone meal combustion residues represent a valuable alternative apatite source for environmental application.

  6. Development of primers for detection of heat-treated cetacean materials in porcine meat and bone meal.

    Science.gov (United States)

    Shinoda, Naoki; Yoshida, Tomotaro; Kusama, Toyoko; Takagi, Masami; Onodera, Takashi; Sugiura, Katsuaki

    2009-07-01

    The feed ban introduced after the detection of the first case of bovine spongiform encephalopathy in 2001 in Japan has been modified to allow some of the previously prohibited animal materials to be used in animal feed. Recently, porcine materials were allowed to be used in feed for pigs, poultry, and fish. Materials from other mammals, including whales, remain prohibited. In the absence of a method to detect the prohibited whale materials in porcine materials, there is a possibility that the whale materials are being used for feed for pigs, poultry, and fish. To detect illegal use of whale materials mixed with porcine materials, we have developed PCR primers specific to a group of most cetacean species, using a computer-based method we developed previously. The primer sets were capable of detecting whale meat meal that had been autoclaved at 133 degrees C for up to 20 min. The detection limit of whale material in porcine meat and bone meal was 0.1%.

  7. Bone augmentation procedures in localized defects in the alveolar ridge: clinical results with different bone grafts and bone-substitute materials

    DEFF Research Database (Denmark)

    Jensen, Simon Storgård; Terheyden, Hendrik

    2009-01-01

    periods. The heterogeneity of the available data did not allow identifying one superior grafting protocol for any of the osseous defect types under investigation. However, a series of grafting materials can be considered well-documented for different indications based on this review. There is a high level......PURPOSE: The objective of this review was to evaluate the efficacy of different grafting protocols for the augmentation of localized alveolar ridge defects. MATERIALS AND METHODS: A MEDLINE search and an additional hand search of selected journals were performed to identify all levels of clinical...... evidence except expert opinions. Any publication written in English and including 10 or more patients with at least 12 months of follow-up after loading of the implants was eligible for this review. The results were categorized according to the presenting defect type: (1) dehiscence and fenestration...

  8. Geometrical and material parameters to assess the macroscopic mechanical behaviour of fresh cranial bone samples.

    Science.gov (United States)

    Auperrin, Audrey; Delille, Rémi; Lesueur, Denis; Bruyère, Karine; Masson, Catherine; Drazétic, Pascal

    2014-03-21

    The present study aims at providing quantitative data for the personalisation of geometrical and mechanical characteristics of the adult cranial bone to be applied to head FE models. A set of 351 cranial bone samples, harvested from 21 human skulls, were submitted to three-point bending tests at 10 mm/min. For each of them, an apparent elastic modulus was calculated using the beam's theory and a density-dependant beam inertia. Thicknesses, apparent densities and percentage of ash weight were also measured. Distributions of characteristics among the different skull bones show their symmetry and their significant differences between skull areas. A data analysis was performed to analyse potential relationship between thicknesses, densities and the apparent elastic modulus. A specific regression was pointed out to estimate apparent elastic modulus from the product of thickness by apparent density. These results offer quantitative tools in view of personalising head FE models and thus improve definition of local injury criteria for this body part.

  9. Altered microRNA expression profile in exosomes during osteogenic differentiation of human bone marrow-derived mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Ji-Feng Xu

    Full Text Available The physiological role of microRNAs (miRNAs in osteoblast differentiation remains elusive. Exosomal miRNAs isolated from human bone marrow-derived mesenchymal stem cells (BMSCs culture were profiled using miRNA arrays containing probes for 894 human matured miRNAs. Seventy-nine miRNAs (∼8.84% could be detected in exosomes isolated from BMSC culture supernatants when normalized to endogenous control genes RNU44. Among them, nine exosomal miRNAs were up regulated and 4 miRNAs were under regulated significantly (Relative fold>2, p<0.05 when compared with the values at 0 day with maximum changes at 1 to 7 days. Five miRNAs (miR-199b, miR-218, miR-148a, miR-135b, and miR-221 were further validated and differentially expressed in the individual exosomal samples from hBMSCs cultured at different time points. Bioinformatic analysis by DIANA-mirPath demonstrated that RNA degradation, mRNA surveillance pathway, Wnt signaling pathway, RNA transport were the most prominent pathways enriched in quantiles with differential exosomal miRNA patterns related to osteogenic differentiation. These data demonstrated exosomal miRNA is a regulator of osteoblast differentiation.

  10. Altered MicroRNA Expression Profile in Exosomes during Osteogenic Differentiation of Human Bone Marrow-Derived Mesenchymal Stem Cells

    Science.gov (United States)

    Zhang, Shui-Jun; Zhao, Chen; Qiu, Bin-Song; Gu, Hai-Feng; Hong, Jian-Fei; Cao, Li; Chen, Yu; Xia, Bing; Bi, Qin; Wang, Ya-Ping

    2014-01-01

    The physiological role of microRNAs (miRNAs) in osteoblast differentiation remains elusive. Exosomal miRNAs isolated from human bone marrow-derived mesenchymal stem cells (BMSCs) culture were profiled using miRNA arrays containing probes for 894 human matured miRNAs. Seventy-nine miRNAs (∼8.84%) could be detected in exosomes isolated from BMSC culture supernatants when normalized to endogenous control genes RNU44. Among them, nine exosomal miRNAs were up regulated and 4 miRNAs were under regulated significantly (Relative fold>2, p<0.05) when compared with the values at 0 day with maximum changes at 1 to 7 days. Five miRNAs (miR-199b, miR-218, miR-148a, miR-135b, and miR-221) were further validated and differentially expressed in the individual exosomal samples from hBMSCs cultured at different time points. Bioinformatic analysis by DIANA-mirPath demonstrated that RNA degradation, mRNA surveillance pathway, Wnt signaling pathway, RNA transport were the most prominent pathways enriched in quantiles with differential exosomal miRNA patterns related to osteogenic differentiation. These data demonstrated exosomal miRNA is a regulator of osteoblast differentiation. PMID:25503309

  11. Freezing and thawing of murine bone marrow-derived dendritic cells does not alter their immunophenotype and antigen presentation characteristics.

    Science.gov (United States)

    Mendoza, L; Bubeník, J; Indrová, M; Bieblová, J; Vonka, V; Símová, J

    2002-01-01

    The aim of this paper was to assess whether the BMDC after freezing and thawing are capable to retain the immunophenotype and antigen-presenting capacity. BMDC were generated from bone marrow precursor cells as described previously by culturing the cells in medium containing GM-CSF and IL-4. Afterwards, the cells were harvested, counted and used for phenotyping and priming of syngeneic spleen cells. For cryopreservation, the BMDC were frozen in the presence of 10% of dimethylsulphoxide (DMSO) and 90% foetal calf serum. Forty to fifty percent of both samples, frozen/thawed as well as fresh BMDC, exhibited characteristic DC morphology, and the DC obtained from the frozen/thawed samples expressed a similar level of MHC class I-, MHC class II-, CD80-, CD86-, CD11c-, CD11b-, CD54- and CD205-molecule as fresh DC. To examine the in vitro priming effect of cryopreserved BMDC on syngeneic non-adherent murine C57BL/6 (B6) spleen cells, the BMDC were thawed, pulsed with the lysate prepared from HPV 16-associated tumour MK16 and used for 3H-thymidine assay. The findings of the experiments indicate that fresh as well as cryopreserved murine BMDC preparations pulsed with tumour lysate were efficient to prime the mitogenic activity of syngeneic non-adherent splenocytes. Taken together, the results suggest that frozen/thawed BMDC are morphologically, phenotypically and functionally comparable with fresh BMDC and can be used for construction of dendritic cell-based tumour vaccines.

  12. Smooth surface micro finite element modelling of a cancellous bone analogue material.

    Science.gov (United States)

    Leung, S Y; Browne, M; New, A M

    2008-01-01

    Tetrahedral finite element meshes with smooth surfaces can be created from computed tomography scans of cancellous bone in order to evaluate its mechanical properties. Image processing before creation of the mesh can affect the accuracy of determined mechanical properties. For a cancellous bone analogue, threshold, mesh density and surface smoothing parameters used in mesh generation were varied and the mechanical properties predicted by the resulting meshes were compared to experimental results. This study has shown that threshold selection is vital for accurate determination of volume fraction and resulting mechanical properties.

  13. Geometrical and material parameters to assess the macroscopic mechanical behaviour of fresh cranial bone samples

    OpenAIRE

    AUPERRIN, Audrey; Delille, Rémi; LESUEUR, Denis; BRUYERE, Karine; Masson, Catherine; Drazetic, Pascal

    2014-01-01

    The present study aims at providing quantitative data for the personalisation of geometrical and 21 mechanical characteristics of the adult cranial bone to be applied to head FE models. A set of 351 22 cranial bone samples, harvested from 21 human skulls, were submitted to three-point bending tests 23 at 10 mm/min. For each of them, an apparent elastic modulus was calculated using the beam's 24 theory and a density-dependant beam inertia. Thicknesses, apparent densities and percentage of ash ...

  14. Fabrication and materials properties of high-density polyethylene (HDPE)/biphasic calcium phosphate (BCP) hybrid bone plates

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Sun Young; Youn, Min Ho; Lim, Youn Mook; Gwon, Hui Jeong; Park, Jong Seok; Nho, Young Chang [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-06-15

    Biphasic calcium phosphate-reinforced high-density polyethylene (BCP/HDPE) hybrid composite is a new orthopedic biomaterial, which was made to simulate a natural bone composition. Calcium phosphate systems and HDPE hybrid composites have been used in biomedical applications without any inflammatory response. Differences in natural bone of both materials have motivated the use of coupling agents to improve their interfacial interfacial interactions. The composites were prepared using medical grade BCP powder and granular polyethylene. This material was produced by replacing the mineral component and collagen soft tissue of the bone with BCP and HDPE, respectively. As expected, increased volume fraction of either reinforcement type over 0 {approx} 50 vol.% resulted in a increased Vickers hardness and Young's modulus. Thus, BCP particle-reinforced HDPE composites possessed improved material and mechanical properties. BCP particles-reinforced composites were anisotropic due to an alignment of the particles in the matrix during a processing. On the other hand, bending and tensile strength was dramatically changed in the matrix. To change the material and mechanical properties of HDPE/BCP composites, the process of a blending was used, and its effect on the microstructure and mechanical proprieties of HDPE/BCP composites were investigated by means of FT-IR/ATR spectroscopy, XRD, FE-SEM, Vickers Hardness Testing Machine, Universal Testing Machine, Mercury Porosimeter and Ultrasonic Flaw Detector at room temperature. For the evaluation of the cell viability and proliferation onto the external surface of HDPE/BCP hybrid plates with a HaCaT cell line, which is a multipotent cell line able to differentiate towards different phenotypes under the action of biological factors, has been evaluated with in vitro studies and quantified by colormetric assays. These findings indicate that the HDPE/BCP hybrid plates are biocompatible and non-toxic.

  15. In vitro degradation and cell response of calcium carbonate composite ceramic in comparison with other synthetic bone substitute materials

    Energy Technology Data Exchange (ETDEWEB)

    He, Fupo [Department of Biomedical Engineering, School of Basic Sciences, Guangzhou Medical University, Guangzhou 510182 (China); Zhang, Jing [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Yang, Fanwen; Zhu, Jixiang; Tian, Xiumei [Department of Biomedical Engineering, School of Basic Sciences, Guangzhou Medical University, Guangzhou 510182 (China); Chen, Xiaoming, E-mail: xmchenw@126.com [Department of Biomedical Engineering, School of Basic Sciences, Guangzhou Medical University, Guangzhou 510182 (China)

    2015-05-01

    The robust calcium carbonate composite ceramics (CC/PG) can be acquired by fast sintering calcium carbonate at a low temperature (650 °C) using a biocompatible, degradable phosphate-based glass (PG) as sintering agent. In the present study, the in vitro degradation and cell response of CC/PG were assessed and compared with 4 synthetic bone substitute materials, calcium carbonate ceramic (CC), PG, hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) ceramics. The degradation rates in decreasing order were as follows: PG, CC, CC/PG, β-TCP, and HA. The proliferation of rat bone mesenchymal stem cells (rMSCs) cultured on the CC/PG was comparable with that on CC and PG, but inferior to HA and β-TCP. The alkaline phosphatase (ALP) activity of rMSCs on CC/PG was lower than PG, comparable with β-TCP, but higher than HA. The rMSCs on CC/PG and PG had enhanced gene expression in specific osteogenic markers, respectively. Compared to HA and β-TCP, the rMSCs on the CC/PG expressed relatively lower level of collagen I and runt-related transcription factor 2, but showed more considerable expression of osteopontin. Although CC, PG, HA, and β-TCP possessed impressive performances in some specific aspects, they faced extant intrinsic drawbacks in either degradation rate or mechanical strength. Based on considerable compressive strength, moderate degradation rate, good cell response, and being free of obvious shortcoming, the CC/PG is promising as another choice for bone substitute materials. - Highlights: • A calcium carbonate composite ceramic (CC/PG) was acquired. • The in vitro degradation and cell response of CC/PG were compared to 4 materials. • The CC/PG showed moderate degradation rate. • The CC/PG exhibited good cell response. • The CC/PG was free of obvious drawback compared to other materials.

  16. [Regeneration processes in bone defects after implantation of composite material of different density of polylactide origin filled with HAP (experimental-morphological study)].

    Science.gov (United States)

    Kulakov, A A; Grigor'ian, A S; Krotova, L I; Popov, V K; Volozhin, A I; Losev, V F

    2009-01-01

    In experimental-morphological study on 6 dogs the dynamics of regenerate formation in ulna and mandible defects after implantation in them composite material of different density (0.46-0.50 and 0.38-0.42 g/cm(3)) of polylactide (PL) origin filled with HAP was followed at the terms of 6 and 9 months. Histologic study and structural determinant distribution analysis in the content of regenerate showed that optimal results according to the bone defect substitution by bone regenerate criterion at 9th month of the experiment were received after composite material from PL and HAP with the density of 0.38-0.42 g/cm(3) implantation. Newly formed trabecular bone tissue was seen in the regenerate and as well as strong tendency for bone matrix maturation. It was confirmed by the appearance of lamellar structures in newly formed bone trabecules situated in peripheral zones of bone defect. In bone mandible defects the substitution process of the implants from PL with HAP by the bone tissue was much slower than in ulna defects.

  17. Anomaly Detection and Comparative Analysis of Hydrothermal Alteration Materials Trough Hyperspectral Multisensor Data in the Turrialba Volcano

    Science.gov (United States)

    Rejas, J. G.; Martínez-Frías, J.; Bonatti, J.; Martínez, R.; Marchamalo, M.

    2012-07-01

    The aim of this work is the comparative study of the presence of hydrothermal alteration materials in the Turrialba volcano (Costa Rica) in relation with computed spectral anomalies from multitemporal and multisensor data adquired in spectral ranges of the visible (VIS), short wave infrared (SWIR) and thermal infrared (TIR). We used for this purposes hyperspectral and multispectral images from the HyMAP and MASTER airborne sensors, and ASTER and Hyperion scenes in a period between 2002 and 2010. Field radiometry was applied in order to remove the atmospheric contribution in an empirical line method. HyMAP and MASTER images were georeferenced directly thanks to positioning and orientation data that were measured at the same time in the acquisition campaign from an inertial system based on GPS/IMU. These two important steps were allowed the identification of spectral diagnostic bands of hydrothermal alteration minerals and the accuracy spatial correlation. Enviromental impact of the volcano activity has been studied through different vegetation indexes and soil patterns. Have been mapped hydrothermal materials in the crater of the volcano, in fact currently active, and their surrounding carrying out a principal components analysis differentiated for a high and low absorption bands to characterize accumulations of kaolinite, illite, alunite and kaolinite+smectite, delimitating zones with the presence of these minerals. Spectral anomalies have been calculated on a comparative study of methods pixel and subpixel focused in thermal bands fused with high-resolution images. Results are presented as an approach based on expert whose main interest lies in the automated identification of patterns of hydrothermal altered materials without prior knowledge or poor information on the area.

  18. Fabrication of highly porous scaffold materials based on functionalized oligolactides and preliminary results on their use in bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Vogt S.

    2002-12-01

    Full Text Available Tissue engineering offers a promising new approach to repair bone defects. Its practical realisation is connected with the development of suitable scaffold materials. In the present work, functionalized oligolactides have been prepared and used as macromers for the scaffold fabrication The developed fabrication process leads to highly porous scaffolds, available in various shapes and sizes, with an open inter-connective pore structure and porosities up to 90 %. Degradable or even osteoconductive components as well as biocompatible co-monomers can be used as additives to modulate the scaffold properties. Under in vitro conditions, the scaffolds exhibit a continuous degradation with varying degradation rates depending on their material composition. In vitro studies on the cultivation of osteoblasts on the scaffolds were performed and revealed their excellent biocompatibility. Cell growth on the scaffold surfaces and inside the scaffolds, formation of extracellular matrix and starting mineralization were detected by microscopical and histological analyses. Based on these results the developed materials are well-suited candidates for the design of tailor-made matrices in bone tissue engineering

  19. Bone cutting.

    Science.gov (United States)

    Giraud, J Y; Villemin, S; Darmana, R; Cahuzac, J P; Autefage, A; Morucci, J P

    1991-02-01

    Bone cutting has always been a problem for surgeons because bone is a hard living material, and many osteotomes are still very crude tools. Technical improvement of these surgical tools has first been their motorization. Studies of the bone cutting process have indicated better features for conventional tools. Several non-conventional osteotomes, particularly ultrasonic osteotomes are described. Some studies on the possible use of lasers for bone cutting are also reported. Use of a pressurised water jet is also briefly examined. Despite their advantages, non-conventional tools still require improvement if they are to be used by surgeons.

  20. Biologically Inspired Self-assembling Synthesis of Bone-like Nano-hydroxyapatite/PLGA- (PEG-ASP)n Composite: A New Biomimetic Bone Tissue Engineering Scaffold Material

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A new biomimetic bone tissue engineering scaffold material, nano-HA/ PLGA-( PEG- ASP )n composite, was synthesized by a biologically inspired self assembling approach. A novel biodegradable PLGA( PEG-ASP ) n copolymer with pendant amine functional groups and enhanced hydrophilicity was synthesized by bulk ring-opening copolymerization by DL-lactide( DLLA ) and glycolide( GA ) with Aspartic acid ( ASP )-Polyethylene glycol( PEG ) alt-prepolymer. A Three-dimensional, porous scaffold of the PLGA-( PEG-ASP )n copolymer was fabricated by a solvent casting, particulate leaching process. The scaffold was then incubated in modified simulated body fluid ( mSBF ) . Growth of HA nanocrystals on the inner pore surfaces of the porous scaffold is confirmed by calcium ion binding analyses, SEM, mass increase measurements and quantification of phosphate content within scaffolds . SEM analysis demonstrated the nucleation and growth of a continuous bonelike, low crystalline carbonated HA nanocrystals on the inner pore surfawes of the PLGA-( PEG-ASP)n scaffolds. The amount of calcium binding, total mass and the mass of pbosphate on experimental PLGA-( PEG- ASP )n scaffolds at different incubation times in mSBF was significantly greater than that of control PLGA scaffolds . This nano-HA/ PLGA- ( PEG-ASP )n composite shows some features of natural bone both in main composition and hierarchical microstructure. The ASPPEG alt-prepolymer modified PLGA copolymer provide a controllable high surface density and distribution of anionic functional groups which would enhauce nucleation and growth of bonelike mineral following exposure to mSBF. This biomimetic treatment provides a simple method for surface funetionalization and subsequent mineral nucleation and self-assembling on biodegradable polymer scaffolds for tissue engineering.

  1. Microscopy and image analysis based approaches for the species-specific identification of bovine and swine bone containing material

    Directory of Open Access Journals (Sweden)

    Matteo Ottoboni

    2014-05-01

    Full Text Available The aim of this study was to evaluate the potential of image analysis measurements in combination with the official analytical method for the detection of constituents of animal origin in feedstuffs, in distinguishing between bovine and swine (bone containing material. Authentic samples of controlled origin containing bovine or swine meat and bone meals were analysed by the microscopic method, in accordance with the official analytical method. Sediment fractions of each sample were observed with a compound microscope at X40. A total of 362 bone fragment lacunae images were recorded and processed through image analysis software, deriving 30 geometric variables for each lacuna. Results indicated that not only were most variables significantly (P<0.001 different between bovine and swine samples, but also that two thirds of the same variables were bigger in bovine than in swine. This information, however, does not seem to be so effective in practice since bovine and swine features and measurements overlapped. It can be concluded that the microscopic method even when combined with image analysis does not fit all the requirements for accurately identifying prohibited ingredients of animal origin. A combined approach with other methods is therefore recommended.

  2. 人工骨材料修复骨缺损:多种复合后的生物学与力学特征%Artificial bone materials for bone defect repair:biomechanical characteristics of multiple composites

    Institute of Scientific and Technical Information of China (English)

    杨毅; 毕鑫; 李多玉; 唐一萍; 李彪

    2014-01-01

    背景:当前应用广泛的骨缺损修复方式主要有自体骨移植、异体骨移植和人工骨移植,人工骨移植可避免患者自身取材的痛苦和并发症及同种异体骨免疫排斥的危险。目的:综述近几年来国内外常用的几种人工骨材料的研究进展情况。方法:应用计算机检索2007至2013年中国期刊全文数据库、PubMed 数据库、中国生物医学文献数据库、FMJS 数据库中有关人工骨材料的研究。中文检索词为“人工骨,材料,骨缺损,骨移植”,英文检索词为“artificial bone,material,bone defect,bone graft”。结果与结论:目前常用的人工骨材料有天然高分子材料、人工合成高分子、无机材料、纳米材料。理想的骨移植替代物应该具备以下条件:良好的生物相容性;局部形成微酸性生物环境;利于血管和成骨细胞长入;可完全生物降解;兼具骨生成性、骨传导性和骨诱导性。生物蛋白胶降解及组织相容性较好,且可塑形,但强度较差,以后研究方向主要为加强其强度。人工合成及无机材料强度及支架作用较好,但组织相容性较差,提高其组织相容性很重要。纳米材料为较合适的人工骨材料。目前应用于骨组织工程研究的人工骨材料均有各自的长处和不足,尚不能同时满足理想的骨组织工程细胞外基质材料各方面的要求,而且在生物学和力学特性上与天然骨有差异,故将多种类型材料复合并进行结构和功能修饰,是研制理想骨缺损修复材料的方向。%BACKGROUND:The current widely used methods of bone defect repair mainly include bone autograft, alograft and artificial bone transplantation. Artificial bone graft can avoid the pain resulting from taking patients’ own materials, complications and risk of alograft immune rejection. OBJECTIVE:To review the research progress in some commonly used artificial bone

  3. Histomorphometric Assessment of Cancellous and Cortical Bone Material Distribution in the Proximal Humerus of Normal and Osteoporotic Individuals: Significantly Reduced Bone Stock in the Metaphyseal and Subcapital Regions of Osteoporotic Individuals.

    Science.gov (United States)

    Sprecher, Christoph M; Schmidutz, Florian; Helfen, Tobias; Richards, R Geoff; Blauth, Michael; Milz, Stefan

    2015-12-01

    Osteoporosis is a systemic disorder predominantly affecting postmenopausal women but also men at an advanced age. Both genders may suffer from low-energy fractures of, for example, the proximal humerus when reduction of the bone stock or/and quality has occurred.The aim of the current study was to compare the amount of bone in typical fracture zones of the proximal humerus in osteoporotic and non-osteoporotic individuals.The amount of bone in the proximal humerus was determined histomorphometrically in frontal plane sections. The donor bones were allocated to normal and osteoporotic groups using the T-score from distal radius DXA measurements of the same extremities. The T-score evaluation was done according to WHO criteria. Regional thickness of the subchondral plate and the metaphyseal cortical bone were measured using interactive image analysis.At all measured locations the amount of cancellous bone was significantly lower in individuals from the osteoporotic group compared to the non-osteoporotic one. The osteoporotic group showed more significant differences between regions of the same bone than the non-osteoporotic group. In both groups the subchondral cancellous bone and the subchondral plate were least affected by bone loss. In contrast, the medial metaphyseal region in the osteoporotic group exhibited higher bone loss in comparison to the lateral side.This observation may explain prevailing fracture patterns, which frequently involve compression fractures and certainly has an influence on the stability of implants placed in this medial region. It should be considered when planning the anchoring of osteosynthesis materials in osteoporotic patients with fractures of the proximal humerus.

  4. EXPERIMENTAL DEVELOPMENT OF BIO-BASED POLYMER MATRIX BUILDING MATERIAL AND FISH BONE DIAGRAM FOR MATERIAL EFFECT ON QUALITY

    Directory of Open Access Journals (Sweden)

    Asmamaw Tegegne

    2014-06-01

    Full Text Available These days cost of building materials are continuously increasing and the conventional construction materials for this particular purpose become low and low. The weight of conventional construction materials particularly building block is heavy and costly due to particularly cement. Thus, the objective of this paper is to develop an alternative light weight, high strength and relatively cost effective building material that satisfy the quality standard used in the country. A bio-based polymer matrix composite material for residential construction was experimentally developed. Sugar cane bagasse, thermoplastics (polyethylene g roup sand and red ash were used as materials alternatively. Mixing of the additives,melting of the hermoplastics, molding and curing (dryingwere the common methods used on the forming process of the samples. Mechanical behavior evaluation (testing of the product was carried out. Totally 45 specimens were produced and three replicate tests were performed per each test type. Quality analysis was carried out for group B material using Ishikawa diagram. The tensile strength of group A specimen was approximately 3 times greater than that of group B specimens. The compression strength of group A specimens were nearly 2 times greater than group B. Comparing to the conventional building materials(concert block and agrostoneproduced in the country, which the compression strength is 7Mpa and 16Mpa respectively, the newly produced materials show much better results in which Group A is 25.66 Mpa and group B is 16.66 Mpa. energy absorption capacity of group A specimens was approximately 3 times better than that of group B. Water absorption test was carried out for both groups and both showed excellent resistivity. Group A composite material specimens, showed better results in all parameters.

  5. Development of multi-substituted 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

    2017-02-15

    Ionic substitutions have been proposed as a tool to control the functional behavior of synthetic hydroxyapatite (HA), particularly for Bone Tissue Engineering (BTE) applications. The effect of simultaneous substitution of different levels of carbonate (CO3 ) 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 (0.58wt% Si) and SiCHA-2 (0.45wt% Si) showed missing bands for CO3 and Si using FTIR analysis, indicating competition for occupation of the phosphate site in the HA lattice. 500°C was considered the most favourable calcination temperature as: (i) the powders produced possessed a similar amount of CO3 (2-8wt%) and Si (<1.0wt%) as present in native bone; and (ii) there was a minimal loss of CO3 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 behaviour to a greater extent than other powders. This article is protected by copyright. All rights reserved.

  6. Physical and chemical characterisation of crude meat and bone meal combustion residue: "waste or raw material?".

    Science.gov (United States)

    Deydier, Eric; Guilet, Richard; Sarda, Stéphanie; Sharrock, Patrick

    2005-05-20

    As a result of the recent bovine spongiform encephalopathy (BSE) crisis in the European beef industry, the use of animal by-product is now severely controlled. Meat and bone meal (MBM) production can no longer be used to feed cattle and must be safely disposed of or transformed. Main disposal option is incineration, producing huge amounts of ashes the valorisation of which becomes a major concern. The aim of this work is to characterise MBM combustion residue in order to evaluate their physical and chemical properties to propose new valorisation avenues. The thermal behaviour of crude meat and bone meal was followed by thermogravimetric analysis (TGA) and (24 wt.%) inorganic residue was collected. The resulting ashes were characterised by powder X-ray diffraction (XRD), particle size distribution, specific surface area (BET), scanning electron microscopy (SEM) couple with energy disperse X-ray analysis (EDX). Elemental analysis revealed the presence of chloride, sodium, potassium, magnesium with high level of phosphate (56 wt.%) and calcium (31 wt.%), two major constituents of bone, mainly as a mixture of Ca10(PO4)6(OH)2 and Ca3(PO4)2 phases. The impact of combustion temperature (from 550 to 1000 degrees C) on the constitution of ashes was followed by TGA, XRD and specific surface measurements. We observed a strong decrease of surface area for the ashes with crystallisation of calcium phosphates phases without major changes of chemical composition.

  7. Effects of composition of biocomposite materials implanted into hole defects of the metaphysis on the reparative regeneration and mineralization of bone tissue.

    Science.gov (United States)

    Luneva, S N; Talashova, I A; Osipova, E V; Nakoskin, A N; Emanov, A A

    2013-12-01

    We carried out a comparative analysis of morphological pattern and element composition of regenerated bone tissue forming in the metaphysis defects after substitution of these defects with calcium phosphate substance containing low-molecular non-collagen bone proteins with various affinities to ion exchangers. We have found that regenerated tissue in the defects grew from the edges to the center and its element composition depended on the maturity of newly formed bone tissue. Implantation material containing non-collagen bone proteins with various affinities to ion exchangers induced no significant changes in the content of analyzed elements of bone tissue around the defect. The content of analyzed elements in the areas distant from the defect area did not change during the experiment.

  8. Micro-finite element simulation of trabecular-bone post-yield behaviour--effects of material model, element size and type.

    Science.gov (United States)

    Verhulp, E; Van Rietbergen, B; Muller, R; Huiskes, R

    2008-08-01

    Micro-finite element (micro-FE) analysis became a standard tool for the evaluation of trabecular bone mechanical properties. The accuracy of micro-FE models for linear analyses is well established. However, the accuracy of recently developed nonlinear micro-FE models for simulations of trabecular bone failure is not known. In this study, a trabecular bone specimen was compressed beyond the apparent yield point. The experiment was simulated using different micro-FE meshes with different element sizes and types, and material models based on cortical bone. The results from the simulations were compared with experimental results to study the effects of the different element and material models. It was found that a decrease in element size from 80 to 40 mum had little effect on predicted post-yield behaviour. Element type and material model had significant effects. Nevertheless, none of the established material models for cortical bone were able to predict the typical descent in the load-displacement curve seen during compression of trabecular bone.

  9. Toxoplasma gondii is dependent on glutamine and alters migratory profile of infected host bone marrow derived immune cells through SNAT2 and CXCR4 pathways.

    Directory of Open Access Journals (Sweden)

    I-Ping Lee

    Full Text Available The obligate intracellular parasite, Toxoplasma gondii, disseminates through its host inside infected immune cells. We hypothesize that parasite nutrient requirements lead to manipulation of migratory properties of the immune cell. We demonstrate that 1 T. gondii relies on glutamine for optimal infection, replication and viability, and 2 T. gondii-infected bone marrow-derived dendritic cells (DCs display both "hypermotility" and "enhanced migration" to an elevated glutamine gradient in vitro. We show that glutamine uptake by the sodium-dependent neutral amino acid transporter 2 (SNAT2 is required for this enhanced migration. SNAT2 transport of glutamine is also a significant factor in the induction of migration by the small cytokine stromal cell-derived factor-1 (SDF-1 in uninfected DCs. Blocking both SNAT2 and C-X-C chemokine receptor 4 (CXCR4; the unique receptor for SDF-1 blocks hypermotility and the enhanced migration in T. gondii-infected DCs. Changes in host cell protein expression following T. gondii infection may explain the altered migratory phenotype; we observed an increase of CD80 and unchanged protein level of CXCR4 in both T. gondii-infected and lipopolysaccharide (LPS-stimulated DCs. However, unlike activated DCs, SNAT2 expression in the cytosol of infected cells was also unchanged. Thus, our results suggest an important role of glutamine transport via SNAT2 in immune cell migration and a possible interaction between SNAT2 and CXCR4, by which T. gondii manipulates host cell motility.

  10. Computer modelling integrated with micro-CT and material testing provides additional insight to evaluate bone treatments: Application to a beta-glycan derived whey protein mice model.

    Science.gov (United States)

    Sreenivasan, D; Tu, P T; Dickinson, M; Watson, M; Blais, A; Das, R; Cornish, J; Fernandez, J

    2016-01-01

    The primary aim of this study was to evaluate the influence of a whey protein diet on computationally predicted mechanical strength of murine bones in both trabecular and cortical regions of the femur. There was no significant influence on mechanical strength in cortical bone observed with increasing whey protein treatment, consistent with cortical tissue mineral density (TMD) and bone volume changes observed. Trabecular bone showed a significant decline in strength with increasing whey protein treatment when nanoindentation derived Young׳s moduli were used in the model. When microindentation, micro-CT phantom density or normalised Young׳s moduli were included in the model a non-significant decline in strength was exhibited. These results for trabecular bone were consistent with both trabecular bone mineral density (BMD) and micro-CT indices obtained independently. The secondary aim of this study was to characterise the influence of different sources of Young׳s moduli on computational prediction. This study aimed to quantify the predicted mechanical strength in 3D from these sources and evaluate if trends and conclusions remained consistent. For cortical bone, predicted mechanical strength behaviour was consistent across all sources of Young׳s moduli. There was no difference in treatment trend observed when Young׳s moduli were normalised. In contrast, trabecular strength due to whey protein treatment significantly reduced when material properties from nanoindentation were introduced. Other material property sources were not significant but emphasised the strength trend over normalised material properties. This shows strength at the trabecular level was attributed to both changes in bone architecture and material properties.

  11. 组织工程骨材料在运动性骨缺损修复中的评价%Evaluation of materials of bone tissue engineering in athletic bone defects reconstruction

    Institute of Scientific and Technical Information of China (English)

    李华

    2011-01-01

    目的:评价组织工程化人工骨材料的性能和应用,找合理的骨缺损修复材料.方法:以"组织工程,缺损,工骨,米材料" 为中文关键词;以"tissue engineering,bone defect,artificial bone,biological degradation"为英文关键词,用计算机检索1993-01/2009-10相关文章.纳入与有关组织工程相关的文章;排除重复研究或Meta分析类文章.以30篇文献为主,点进行了讨论组织工程纳米级人工骨材料的种类及其性能.结果:可生物降解并具有生物活性的组织工程人工骨材料可作为一种较理想的支架材料应用于骨缺损修复组织工程.修复效果相当或接近自体骨,源充足,无免疫排斥反应,避免取自体骨给患者带来的痛苦和并发症,影响运动员重返赛场,动员患者乐于接受.复合材料人工骨在解除运动员患者的后顾之忧的同时,带来巨大的社会效益.基于纳米羟基磷灰石复合重组人骨形态发生蛋白2制成的支架,但具有理想的生物相容性、生物降解性和较高的亲和性,且能提高了骨诱导活性,够促进新骨的形成.可生物降解并具有生物活性的组织工程人工骨材料在临床使用的初步情况表明,人体生物相容性良好,免疫排斥反应,合情况良好.结论:骨缺损是常见的运动损伤,直为运动损伤研究热点.组织工程化骨缺损修复的研究近年来发展迅速,运动损伤骨缺损修复带来了契机.组织工程复合材料可以发挥不同材料的优势,补单一材料的不足,一种比较理想的支架材料.%OBJECTIVE: To evaluate the disposition and application of tissue-engineered artificial bone materials, in order to find a reasonable repair material for bone defect.METHODS: Taking "tissue engineering, bone defect, artificial bone, nanomaterials" in Chinese, and "tissue engineering, bone defect, artificial bone, biological degradation" in English as search terms, the articles between January 1993 and October 2009were

  12. Tissue reaction and material biodegradation of a calcium sulfate/apatite biphasic bone substitute in rat muscle

    Directory of Open Access Journals (Sweden)

    Jian-Sheng Wang

    2016-07-01

    Conclusion: Calcium sulfate hydroxyapatite bone substitute can be used as a carrier for antibiotics or other drugs, without adverse reaction due to the fast resorption of the calcium sulfate. No bone formation was seen despite treating the bone substitute with autologous bone marrow.

  13. Effects of implant surface coatings and composition on bone integration: a systematic review

    NARCIS (Netherlands)

    Junker, R.; Dimakis, A.; Thoneick, M.; Jansen, J.A.

    2009-01-01

    OBJECTIVE: The aim of the present review was to evaluate the bone integration efficacy of recently developed and marketed oral implants as well as experimental surface alterations. MATERIALS AND METHODS: A PubMed search was performed for animal studies, human reports and studies presenting bone-to-i

  14. Altered combustion characteristics of metallized energetics due to stable secondary material inclusion

    Science.gov (United States)

    Terry, Brandon C.

    Though metals and metalloids have been widely considered as reactive fuels, the ability to tune their ignition and combustion characteristics remains challenging. One means to accomplish this may be through low-level inclusion of secondary materials into the metallized fuel. While there are several potential methods to stably introduce secondary inclusion materials, this work focuses on the use of mechanical activation (MA) and metal alloys. Recent work has shown that low-level inclusion of fluoropolymers into aluminum particles can have a substantial effect on their combustion characteristics. The reflected shock ignition of mechanically activated aluminum/polytetrafluoroethylene (MA Al/PTFE) is compared to a physical mixture (PM) of Al/PTFE, neat spherical aluminum, and flake aluminum. It was found that the powders with higher specific surface areas ignited faster than the spherical particles of the same size, and had ignition delay times comparable to agglomerates of aluminum particles that were two orders of magnitude smaller in size. Flake aluminum powder had the same ignition delay as MA Al/PTFE, indicating that any initial aluminum/fluoropolymer reactions did not yield an earlier onset of aluminum oxidation. However, MA Al/PTFE did have a shorter total burn time. The PM of Al/PTFE powder had a shorter ignition delay than neat spherical aluminum due to the rapid decomposition of PTFE into reactive fluorocarbon compounds, but the subsequent fluorocarbon reactions also created a secondary luminosity profile that significantly increased the total burn time of the system. The explosive shock ignition of aluminum and aluminum-silicon eutectic alloy compacts was evaluated with and without polymer inclusions. A statistical analysis was completed, investigating the effects of: detonation train orientation (into or not into a hard surface); the high explosive driver; whether the metal/polymer system is mechanically activated; particle size; particle morphology

  15. Structural properties of a bone-ceramic composite as a promising material in spinal surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kirilova, I. A., E-mail: IKirilova@mail.ru; Sadovoy, M. A.; Podorozhnaya, V. T., E-mail: VPodorognaya@niito.ru; Taranov, O. S. [Novosibirsk Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan, Novosibirsk (Russian Federation); Klinkov, S. V.; Kosarev, V. F. [Christianovich Institute of Theoretical and Applied Mechanics, SB RAS, Novosibirsk (Russian Federation); Shatskaya, S. S. [Institute of Solid State Chemistry and Mechanochemistry, SB RAS, Novosibirsk (Russian Federation)

    2015-11-17

    The paper describes the results of in vitro tests of composite bone-ceramic implants and procedures for modifying implant surfaces to enhance osteogenesis. Analysis of CBCI ESs demonstrated that they have a porous structure with the mean longitudinal pore size of 70 µm and the mean transverse pore size of 46 µm; surface pores are open, while inner pores are closed. Elemental analysis of the CBCI surface demonstrates that CBCIs are composed of aluminum and zirconium oxides and contain HA inclusions. Profilometry of the CBCI ES surface revealed the following deviations: the maximum deviation of the profile in the sample center is 15 µm and 16 µm on the periphery, while the arithmetical mean and mean square deviations of the profile are 2.65 and 3.4 µm, respectively. In addition, CBCI biodegradation products were pre-examined; a 0.9% NaCl solution was used as a comparison group. Potentially toxic and tissue accumulated elements, such as cadmium, cobalt, mercury, and lead, are present only in trace amounts and have no statistically significant differences with the comparison group, which precludes their potential toxic effects on the macroorganism. Ceramic-based CBCI may be effective and useful in medicine for restoration of the anatomic integrity and functions of the bone tissue.

  16. Adult mesenchymal stem cells for bone and cartilage engineering: effect of scaffold materials

    Directory of Open Access Journals (Sweden)

    A Gigante

    2009-08-01

    Full Text Available Bone marrow is a useful cell source for skeletal tissue engineering approaches. In vitro differentiation of marrow mesenchymal stem cells (MSCs to chondrocytes or osteoblasts can be induced by the addition of specific growth factors to the medium. The present study evaluated the behaviour of human MSCs cultured on various scaffolds to determine whether their differentiation can be induced by cell-matrix interactions. MSCs from bone marrow collected from the acetabulum during hip arthroplasty procedures were isolated by cell sorting, expanded and characterised by a flow cytometry system. Cells were grown on three different scaffolds (type I collagen, type I + II collagen and type I collagen + hydroxyapatite membranes and analysed by histochemistry, immunohistochemistry and spectrophotometry (cell proliferation, alkaline phosphatase activity at 15 and 30 days. Widely variable cell adhesion and proliferation was observed on the three scaffolds. MSCs grown on type I+II collagen differentiated to cells expressing chondrocyte markers, while those grown on type I collagen + hydroxyapatite differentiated into osteoblast-like cells. The study highlighted that human MSCs grown on different scaffold matrices may display different behaviours in terms of cell proliferation and phenotype expression without growth factor supplementation.

  17. Structural properties of a bone-ceramic composite as a promising material in spinal surgery

    Science.gov (United States)

    Kirilova, I. A.; Sadovoy, M. A.; Podorozhnaya, V. T.; Taranov, O. S.; Klinkov, S. V.; Kosarev, V. F.; Shatskaya, S. S.

    2015-11-01

    The paper describes the results of in vitro tests of composite bone-ceramic implants and procedures for modifying implant surfaces to enhance osteogenesis. Analysis of CBCI ESs demonstrated that they have a porous structure with the mean longitudinal pore size of 70 µm and the mean transverse pore size of 46 µm; surface pores are open, while inner pores are closed. Elemental analysis of the CBCI surface demonstrates that CBCIs are composed of aluminum and zirconium oxides and contain HA inclusions. Profilometry of the CBCI ES surface revealed the following deviations: the maximum deviation of the profile in the sample center is 15 µm and 16 µm on the periphery, while the arithmetical mean and mean square deviations of the profile are 2.65 and 3.4 µm, respectively. In addition, CBCI biodegradation products were pre-examined; a 0.9% NaCl solution was used as a comparison group. Potentially toxic and tissue accumulated elements, such as cadmium, cobalt, mercury, and lead, are present only in trace amounts and have no statistically significant differences with the comparison group, which precludes their potential toxic effects on the macroorganism. Ceramic-based CBCI may be effective and useful in medicine for restoration of the anatomic integrity and functions of the bone tissue.

  18. Effect of raw material source, processing systems, and processing temperatures on amino acid digestibility of meat and bone meals.

    Science.gov (United States)

    Wang, X; Parsons, C M

    1998-06-01

    Experiments were conducted to evaluate amino acid digestibility of 32 commercial meat and bone meals (MBM) varying in raw material source and produced in seven different commercial cooking systems and at two processing temperatures (low vs high) that differed by 15 to 20 C. Raw material sources included all beef, all pork, mixed species, and high bone MBM. True digestibilities of amino acids were determined using the precision-fed cecectomized rooster assay. Protein efficiency ratio (PER) of six MBM varying greatly in amino acid digestibility was determined with chicks fed 10% CP diets containing a MBM as the sole source of dietary protein. The 32 MBM samples averaged 53.2% CP, 2.73% Lys, 0.6% Cys, and 0.75% Met on a DM basis. True digestibility averaged 82% for Lys, 87% for Met, and 47% for Cys. True digestibilities of amino acids varied substantially among processing systems and temperatures, particularly for Lys and Cys. For example, Lys and Cys digestibility ranged from 68 to 92% and from 20 to 71%, respectively, among different MBM. The higher processing temperature generally yielded lower amino acid digestibility than did the low processing temperature. A smaller, less consistent, effect was observed for raw material source. The PER values of the six selected MBM varied from 0.97 to 2.68 and were highly correlated with amino acid digestibility. These results indicated that very high amino acid digestibility MBM can be produced in commercial rendering systems. However, differences in processing systems and temperatures can cause substantial variability in amino acid digestibilities.

  19. Hyperspectral surface materials map of quadrangle 3262, Farah (421) and Hokumat-e-pur-Chaman (422) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  20. Hyperspectral surface materials map of quadrangle 3462, Herat (409) and Chishti Sharif (410) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  1. Hyperspectral surface materials map of quadrangle 3366, Gizab (513) and Nawer (514) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  2. Hyperspectral surface materials map of quadrangle 3564, Jowand (405) and Gurziwan (406) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  3. Hyperspectral surface materials map of quadrangle 3266, Uruzgan (519) and Moqur (520) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  4. Hyperspectral surface materials map of quadrangle 3562, Khawja-Jir (403) and Murghab (404) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  5. Hyperspectral surface materials map of quadrangle 3362, Shindand (415) and Tulak (416) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  6. Hyperspectral surface materials map of quadrangle 3464, Shahrak (411) and Kasi (412) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  7. Hyperspectral surface materials map of quadrangle 3162, Chakhansur (603) and Kotalak (604) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  8. Hyperspectral surface materials map of quadrangle 3568, Pul-e Khumri (503) and Charikar (504) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  9. Hyperspectral surface materials map of quadrangle 3268, Khayr Kot (521) and Urgun (522) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  10. Hyperspectral surface materials map of quadrangle 3164, Lashkar Gah (605) and Kandahar (606) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  11. Hyperspectral surface materials map of quadrangle 3670, Jurm-Kishim (223) and Zebak (224) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  12. Hyperspectral surface materials map of quadrangle 3166, Jaldak (701) and Maruf-Nawa (702) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  13. Hyperspectral surface materials map of quadrangle 3770, Faizabad (217) and Parkhaw (218) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  14. Hyperspectral surface materials map of quadrangle 3368, Ghazni (515) and Gardez (516) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  15. Hyperspectral surface materials map of quadrangle 3470, Jalalabad (511) and Chaghasaray (512) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  16. Hyperspectral surface materials map of quadrangle 3466, La`l wa Sar Jangal (507) and Bamyan (508) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  17. Hyperspectral surface materials map of quadrangle 3264, Naw Zad-Musa Qala (423) and Dihrawud (424) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  18. Hyperspectral surface materials map of quadrangle 3364, Pasaband (417) and Markaz-e Kajiran (418) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  19. Hyperspectral Surface Materials Map of Quadrangle 3566, Sangcharak (501) and Sayghan-o-Kamard (502) Quadrangles, Afghanistan, Showing Carbonates, Phyllosilicates, Sulfates, Altered Minerals, and Other Materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  20. Hyperspectral surface materials map of quadrangle 3468, Chak-e Wardak-Siyahgird (509) and Kabul (510) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  1. Hyperspectral surface materials map of quadrangle 3570, Tagab-e-Munjan (505) and Asmar-Kamdesh (506) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  2. The Baroque monuments of Modica (Eastern Sicily): assessment of causes of chromatic alteration of stone building materials

    Science.gov (United States)

    Belfiore, Cristina M.; La Russa, Mauro F.; Pezzino, Antonino; Campani, Elisa; Casoli, Antonella

    2010-09-01

    The Baroque monuments of several cities in eastern Sicily, built of local calcarenitic stone, are often subjected to conservation treatments, since they undergo many forms of alteration and degradation which can cause significant damage. However, a recent study of these building materials (Barone et al. in Environ. Geol. 54:1501, 2008) has demonstrated that some protective products, once applied, cause irreversible chromatic alterations. The façades of the monuments of the historic city centre of Modica are typically creamy yellow in colour, sometimes varying slightly due to the use of various pigments, such as clayey and gypseous earths (La Russa et al. in Appl. Phys. A 92:185, 2008). However, in some cases, these nuances are lost due to the application of protective products. This work provides a petrographic and colorimetric characterisation of the calcarenitic stone used to create the façades of the churches of S. Pietro, S. Maria del Soccorso and S. Maria dell’Annunziata in Modica, also by comparisons with locally quarried samples. In addition, it aims to identify protective substances which may have been used during previous restoration work. Analytical techniques included polarising optical microscopy, spectrophotometric colorimetric tests, Fourier-transform infrared spectroscopy (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS).

  3. Osteogenic potential of porous {beta}-tricalcium phosphate ({beta}-TCP) combined with cultured bone. Tissue engineered bone using a biodegradable material as a scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Fu, S.; Yamada, Y.; Honda, M.; Ueda, M. [Nagoya Univ. (Japan). Dept. of Protective Care for Masticatory Disorders; Yoshikawa, T. [Nara Medical Univ. (Japan). First Dept. of Pathology; Hibino, Y.; Hata, K. [Nagoya Univ. (Japan). Dept. of Tissue Engineering; Niimi, A. [Nagoya Univ. (Japan). Dept. of Protective Care for Masticatory Disorders; Chunichi Hospital (Japan). Dept. of Oral and Maxillofacial Surgery; Okazaki, Y. [Nagoya Univ. (Japan). Dept. of Protective Care for Masticatory Disorders; Nagoya Univ. (Japan). Dept. of Tissue Engineering

    2001-07-01

    Recently, the tissue engineering approach has widespread attention for regeneration. The present study was undertaken to evaluate whether biodegradable porous {beta}-tricalcium phosphate ({beta}-TCP) can be used as a scaffold for cultured bone marrow cells or not. Marrow cells were obtained from bone shaft of rat femur and cultured in a standard medium for 10 days, then trypsinized to combine cells with ceramics. An additional subculture was done for cells/ceramics composite in a standard medium with the addition of {beta}-glycerophosphate, ascorbic acid and dexamethason. The 20 day subcultured composites were implanted into subcutaneous sites of syngeneic rats. These implants were harvested at 4 and 8 weeks postimplantation, and prepared for the histological analysis. In the histological analysis of composites at 4 weeks postimplantation, active bone formation could be found in the composites. The bone formation was evidenced by active osteoblast lining on the surfaces of bone. At 8 weeks, more extensive bone formation was observed in the composites. These results suggested that beta-TCP could play a role as scaffold of tissueengineered bone derived from marrow cells. (orig.)

  4. Polyphosphate: A Morphogenetically Active Implant Material Serving as Metabolic Fuel for Bone Regeneration.

    Science.gov (United States)

    Müller, Werner E G; Tolba, Emad; Schröder, Heinz C; Wang, Xiaohong

    2015-09-01

    The initial mineralization centers during human bone formation onto osteoblasts are composed of CaCO3 . Those bioseeds are enzymatically formed via carbonic anhydrase(s) in close association with the cell surface of the osteoblasts. Subsequently, the bicarbonate/carbonate anions are exchanged non-enzymatically by inorganic phosphate [Pi ]. One source for the supply of Pi is polyphosphate [polyP] which is a physiological polymer, formed in the osteoblasts as well as in the platelets. The energy-rich acid anhydride bonds within the polyP chain are cleaved by phosphatase(s); during this reaction free-energy might be released that could be re-used, as metabolic fuel, for the maintenance of the steady-state concentrations of the substrates/products during mineralization. Finally it is outlined that polyP, as a morphogenetically active scaffold, is even suitable for 3D cell printing.

  5. Cross-correlative 3D micro-structural investigation of human bone processed into bone allografts

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Atul Kumar [Centre for Research in Nanotechnology & Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Gajiwala, Astrid Lobo [Tissue Bank, Tata Memorial Hospital, Parel, Mumbai 400012 (India); Rai, Ratan Kumar [Centre of Biomedical Research, SGPGIMS Campus, Lucknow 226014 (India); Khan, Mohd Parvez [Division of Endocrinology, Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI) CSIR-Central Drug Research Institute, Lucknow 226031 (India); Singh, Chandan [Centre of Biomedical Research, SGPGIMS Campus, Lucknow 226014 (India); Barbhuyan, Tarun [Division of Endocrinology, Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI) CSIR-Central Drug Research Institute, Lucknow 226031 (India); Vijayalakshmi, S. [Centre for Research in Nanotechnology & Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Chattopadhyay, Naibedya [Division of Endocrinology, Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI) CSIR-Central Drug Research Institute, Lucknow 226031 (India); Sinha, Neeraj, E-mail: neerajcbmr@gmail.com [Centre of Biomedical Research, SGPGIMS Campus, Lucknow 226014 (India); Kumar, Ashutosh, E-mail: ashutoshk@iitb.ac.in [Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076 (India); Bellare, Jayesh R., E-mail: jb@iitb.ac.in [Centre for Research in Nanotechnology & Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 400076 (India)

    2016-05-01

    Bone allografts (BA) are a cost-effective and sustainable alternative in orthopedic practice as they provide a permanent solution for preserving skeletal architecture and function. Such BA however, must be processed to be disease free and immunologically safe as well as biologically and clinically useful. Here, we have demonstrated a processing protocol for bone allografts and investigated the micro-structural properties of bone collected from osteoporotic and normal human donor samples. In order to characterize BA at different microscopic levels, a combination of techniques such as Solid State Nuclear Magnetic Resonance (ssNMR), Scanning Electron Microscope (SEM), micro-computed tomography (μCT) and Thermal Gravimetric Analysis (TGA) were used for delineating the ultra-structural property of bone. ssNMR revealed the extent of water, collagen fine structure and crystalline order in the bone. These were greatly perturbed in the bone taken from osteoporotic bone donor. Among the processing methods analyzed, pasteurization at 60 °C and radiation treatment appeared to substantially alter the bone integrity. SEM study showed a reduction in Ca/P ratio and non-uniform distribution of elements in osteoporotic bones. μ-CT and MIMICS® (Materialize Interactive Medical Image Control System) demonstrated that pasteurization and radiation treatment affects the BA morphology and cause a shift in the HU unit. However, the combination of all these processes restored all-important parameters that are critical for BA integrity and sustainability. Cross-correlation between the various probes we used quantitatively demonstrated differences in morphological and micro-structural properties between BA taken from normal and osteoporotic human donor. Such details could also be instrumental in designing an appropriate bone scaffold. For the best restoration of bone microstructure and to be used as a biomaterial allograft, a step-wise processing method is recommended that preserves all

  6. 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 ...

  7. 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.

  8. Bioactivity and degradability of hybrids nano-composites materials with great application as bone tissue substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Téllez, D.A.; Téllez-Jurado, L.; Chávez-Alcalá, J.F., E-mail: fchaveza@hotmail.com

    2014-12-05

    Highlights: • pH has an effect on the degradation process of the hybrid materials. • Weight loss depends on the change of pH during the degradation process. • Bioactivity in the materials is strongly related to calcium and pH. - Abstract: In this work, hybrids with great application as bioactive materials having different compositions based on siloxane network were prepared. In vitro bioactivity and in vitro degradability tests were carried out in the materials by soaking them into simulated body fluid (SBF) and into phosphate buffer solution (PBS) to prove their apatite-forming ability and to show their degradation process, respectively. In both in vitro tests, measurements of pH and loss weight were made to observe bioactivity and degradation processes. To prove growth of HA, the materials were characterized through X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The results showed that some samples have better bioactivity than others. It was found that the incorporation of CaO component into the network of the materials results in an increase of the apatite-forming ability in SBF. Moreover, during the degradation tests, all the samples presented weight loss, especially the ones that contain CaO.

  9. Alteration and long-term behaviour of different types of innovative materials for long-lived radionuclides confinement; Alteration et comportement a long terme de differentes classes de materiaux innovants pour le confinement des radionucleides a vie longue

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G

    1998-09-29

    The present work is an experimental study on alteration mechanisms of synthetic and natural materials: aluminosilicate glasses, glass ceramics and Ti, Zr or P based ceramics. It is a part of CEA's study program on the immobilization of long- lived radionuclides and deals with chemical processes which control dissolution of amorphous and crystallized solids. The different aluminosilicate glasses studied are altered according to a process of hydrolysis of the bonds between the glass network formers; the activation energy of this reaction is about 60 kJ/mol. Alteration rates of all the glasses decrease by four orders of magnitude when the reaction progress increases. Kinetic laws based on the deviation from the thermodynamic equilibrium between leachate and the fresh solid cannot explain these great decreases. Alteration layers in the reactional interface seem to control the alteration kinetics by providing a passivation process. The chemical durability of the glass ceramics (zirconolite and titanite) improves by a factor of ten in regard to the primary glasses which were obtained by thermal treatment. Zirconium-titanate ceramics are altered only slightly by water. The altered mass corresponds to a few atomic layers only. Steady stases are quickly observed. On the basis of thermodynamic calculations, they are not correlated with saturation between the leachate and primary zirconium-titanate phases. Alteration here also ceases due to the development of a passivating layer. Models aiming at studying the chemical durability of zirconium-titanate ceramics under conditions more representative of a clayey site of geological storage were carried out. The results of the interactions of these ceramics with clays, at 708 deg.C, show clearly that there is no modification of the process of alteration, compared to the simpler pure water systems. Thus, perovskite and zirconolite do not deteriorate under these conditions. (author)

  10. Relleno de cavidades óseas en cirugía maxilofacial con materiales autólogos Bone cavity augmentation in maxillofacial surgery using autologous material

    Directory of Open Access Journals (Sweden)

    P. Infante-Cossío

    2007-02-01

    Full Text Available Aunque se han descrito numerosos materiales para rellenar una cavidad ósea, el mejor material sigue siendo el hueso autólogo corticoesponjoso o particulado, que puede formar hueso nuevo por mecanismos de osteogénesis, osteinducción y osteoconducción. El cirujano oral y maxilofacial debe conocer las propiedades biológicas y las características fundamentales de los materiales autólogos, las diferentes técnicas de obtención y sus aplicaciones clínicas. Como zonas donantes se emplean preferentemente las intraorales, el filtro de hueso y los raspadores para pequeños defectos, y el hueso ilíaco, tibia o calota cuando se requiere más cantidad. No existen estudios concluyentes respecto a la asociación de injertos óseos con membranas. La combinación de injertos autólogos con otros materiales de relleno, ha desembocado en múltiples estudios, sin que se puedan establecer conclusiones definitivas por el momento. El hueso autólogo es de elección para el relleno de cavidades óseas, ya que es útil para dar solución a variadas situaciones clínicas de forma simple, rápida y segura.Although a large number of materials have been described for augmenting bone cavities, the best material is still autologous cortical-cancellous bone or bone chip, which can form new bone through osteogenesis, osteoinduction and osteoconduct ion mechanisms. The oral and maxillofacial surgeon needs to be familiar with the biological properties and the fundamental characteristics of autologous material, the different techniques for obtaining it and its clinical application. Donor sites should preferably be intraoral. Bone filters and scrapers should be used for small defects, and the iliac, tibial or calvaria bones [should be used] when more quantity is required. There are no conclusive studies with regard to combining bone grafts with membranes. The combination of autologous grafts with other augmentation material has led to multiple studies, although

  11. Material properties and in vitro biocompatibility of a newly developed bone cement

    Directory of Open Access Journals (Sweden)

    Elke Mitzner

    2009-01-01

    Full Text Available In this study mechanical properties and biocompatibility (In Vitro of a new bone cement were investigated. A new platform technology named COOL is a variable composite of dissolved, chemically modified PMMA and different bioceramics. COOL cures at body temperature via a classical cementation reaction. Compressive strengths ranging from 3.6 ± 0.8 to 62.8 ± 1.3 MPa and bending strengths ranging from 9.9 ± 2.4 to 26.4 ± 3.0 MPa were achieved with different COOL formulations. Porosity varied between 31 and 43%. Varying the components of each formulation mechanical properties and porosity could be adjusted. In Vitro biocompatibility studies with primary human osteoblasts (pHOB in direct contact with different COOL formulations, did not reveal any signs of toxicity. In contrast to Refobacin® R, cells incubated with COOL showed similar density, viability and ALP activity compared to control, if specimen were added immediately to the cell monolayer after preparation. In conclusion, COOL has promising mechanical properties in combination with high biocompatibility In Vitro and combines different advantages of both CPCs and PMMA cements by avoiding some of the respective shortcomings.

  12. [Study of regeneration in periodontal tissue after implantation of bone ceramic and collagen gel compound materials. Evaluation of histopathological finding and autoradiography].

    Science.gov (United States)

    Miyamoto, Y; Hayashi, H; Kamoi, K

    1989-12-01

    The aim of this study is to determine the process of periodontal tissue regeneration and the metabolic activity of osteoblasts after implantation of bone ceramic and collagen gel compound materials (BC). Bone defects were artificially prepared in the alveolar septa of the bilateral upper first and second molars of Wistar rats. Subsequently, BC were implanted into the defective sites on the left side, and the gingival flaps were closed. At the defective sites on the right side, as a control, gingival flaps were closed without implantation. Rats were sacrificed 1, 3, 5, 7 or 14 weeks after implantation, and prepared tissue sections were observed both pathologically and autoradiographically using 3H-Proline. The results obtained were as follows: Pathological Findings One week after BC implantation, inflammatory cellular infiltration of the surrounding gingival connective tissue was relatively mild. Three weeks after implantation, BC were present in fibrous connective tissues, and some directly bound to the marices of regenerated bone. Observation 5 weeks after implantation revealed that BC had become embedded in the regenerated bone matrices and that there was giant cell reaction to foreign bodies at the margin of BC located in connective tissue. BC were directly bound to the regenerated bone matrices without intermediary fibrous tissues 7 and 14 weeks after implantation. Connective tissues showed high grade regeneration of collagen fiber bundles, in an arrangement that tended to be fixed in mesial and distal directions. Autoradiographic Findings There was no uptake of 3H-Proline into the regenerated bone matrices or the gingival connective tissue surrounding BC, while uptake of 3H-Proline into the entire area around the root apex and in the vicinity of the alveolar septum was observed with time (weeks) after BC implantation. These results suggest that BC provide nuclei for bone regeneration through inclusion in newly-generated periodontal bone tissue, although it is

  13. Material Rhetoric: Spreading Stones and Showing Bones in the Study of Prehistory

    NARCIS (Netherlands)

    Van Reybrouck, D.; de Bont, R.; Rock, J.

    2009-01-01

    Since the linguistic turn, the role of rhetoric in the circulation and the popular representation of knowledge has been widely accepted in science studies. This article aims to analyze not a textual form of scientific rhetoric, but the crucial role of materiality in scientific debates. It introduces

  14. Analysis of stress on mucosa and basal bone underlying complete dentures with different reliner material thicknesses: a three-dimensional finite element study.

    Science.gov (United States)

    Lima, J B G; Orsi, I A; Borie, E; Lima, J H F; Noritomi, P Y

    2013-10-01

    The aim of this study was to determine the optimal thickness of reliner material that provides the least amount of stress on thin mucosa and supporting bone in patients with complete removable dentures using a three-dimensional finite element analyses. The model was obtained from two CT scans of edentulous mandibles with dentures supported by the alveolar ridge. After virtual reconstruction, the three-dimensional models were exported to the solidworks cad software and divided into six groups based on the thickness of the reliner material as follows: (i) without material, (ii) 0·5 mm, (iii) 1 mm, (iv) 1·5 mm, (v) 2 mm and (vi) 2·5 mm. The applied load was 60 N and perpendicular to the long axis of the alveolar ridge of all the prosthetic teeth, and the mucosal thickness used was 1 mm. The analyses were based on the maximum principal stress in the fibromucosa and the minimum principal stress in the basal bone. Stress concentration was observed in the anterior zone of the mandible in the mucosa and in the bone. The maximum and minimum principal stress in the mucosa and bone, respectively, decreased, whereas the thickness of the reliner material increased until 2 mm, which transmitted the lowest stress, compared with the control. Reliner materials with a thickness of 2·5 mm showed higher stress values than those with a thickness of 2 mm. In conclusion, reliner material with a thickness of 2 mm transmitted the lowest amount of stress to the mucosa and bone in 1 mm of mucosa thickness.

  15. 脱蛋白松质骨作为异种骨移植材料的修复作用%Repair effect of deproteinised cancellous bone as xenogeneic bone graft material

    Institute of Scientific and Technical Information of China (English)

    高春阳; 姜宏春; 金春明

    2011-01-01

    BACKGROUND: Unequal size, mutual communication, and open pore network structure can be seen in cancellous bone treated with deproteinization. Its inorganic component is hydroxyapatite, and the organic component is collagen, which has a good mechanical property and biocompatibility. It may be a new type of bone graft material.OBJECTIVE: To study the properties of xenogeneic deproteinised cancellous bone being carrier of bone tissue engineering in bone fusion.METHODS: Taking “xenogeneic deproteinised cancellous bone, bone fusion, carrier” in Chinese as search terms, the articles from January 1998 to December 2009 in VIP database, CNKI database, Pubmed database were retrieved by computer. The relevant literatures were included, the literature of irrelevant purpose and repetitive content were excluded, and 33 of them were involved for further analysis.RESULTS AND CONCLUSION: Compared with synthetic bone material, animal bones have similar biomaterial structure, modeling, excellent cell attachment, and cell growth and proliferation environment. However, the compatibility of bone tissue is poor, because of the differences in species when xenogeneic deproteinised cancellous bone transplantation, and gravis immune rejection, the key question is implantation of immune problems. How to overcome immunogenicity, xenogeneic deproteinised cancellous bone is a good carrier of bone tissue engineering, which can provide a stable environment for revascularization and differentiation of osteoblasts.%背景:采用脱蛋白处理后的松质骨可见大小不等、相互交通、开放孔隙的网架结构,其无机成分为羟基磷灰石,有机成分为胶原,力学性能保存良好,有良好的细胞相容性,可能是一种新型骨移植材料.目的:介绍异种脱蛋白松质骨作为骨组织工程载体的性能,以及其用于骨融合的作用.方法:分别以"异种脱蛋白松质骨、骨融合、载体",为检索词,应用计算机检索重庆

  16. Geometric and mechanical properties evaluation of scaffolds for bone tissue applications designing by a reaction-diffusion models and manufactured with a material jetting system

    Directory of Open Access Journals (Sweden)

    Marco A. Velasco

    2016-10-01

    Full Text Available Scaffolds are essential in bone tissue engineering, as they provide support to cells and growth factors necessary to regenerate tissue. In addition, they meet the mechanical function of the bone while it regenerates. Currently, the multiple methods for designing and manufacturing scaffolds are based on regular structures from a unit cell that repeats in a given domain. However, these methods do not resemble the actual structure of the trabecular bone which may work against osseous tissue regeneration. To explore the design of porous structures with similar mechanical properties to native bone, a geometric generation scheme from a reaction-diffusion model and its manufacturing via a material jetting system is proposed. This article presents the methodology used, the geometric characteristics and the modulus of elasticity of the scaffolds designed and manufactured. The method proposed shows its potential to generate structures that allow to control the basic scaffold properties for bone tissue engineering such as the width of the channels and porosity. The mechanical properties of our scaffolds are similar to trabecular tissue present in vertebrae and tibia bones. Tests on the manufactured scaffolds show that it is necessary to consider the orientation of the object relative to the printing system because the channel geometry, mechanical properties and roughness are heavily influenced by the position of the surface analyzed with respect to the printing axis. A possible line for future work may be the establishment of a set of guidelines to consider the effects of manufacturing processes in designing stages.

  17. Realization and testing of multi-material 3D printer for bone scaffold fabrication

    Science.gov (United States)

    Whulanza, Yudan; Hidayaturrahmi, Pretty; Kurniawati, Tri; AJ, Rahyussalim

    2017-02-01

    This research realized 3D constructs by integrating more than one material with multi fabrication system within a single session. A commercial rapid prototyping system, RepRap MendelTM, is modified so that it enables us to realize microenvironment composed of multi materials namely gelatin hydrogel and polylactic acid. Firstly, the session is preceded by realization of 3D scaffold using polylactic acid (PLA) with porosity and modulus elasticity as characterized. Later, the gelatin extrusion took place to seed the cellular in determined spatial arrangement. The results show that our apparatus able to realized scaffold that using PLA as matrix filled with gelatin that act as cell carrier in future application. The scaffolds have porous around 0.25 mm2 porosity with a modulus of elasticity around 160 MPa.

  18. Biocompatibility of Tri-block Bone-matrix Material in vitro

    Institute of Scientific and Technical Information of China (English)

    DUAN Deyu; ZHENG Qixin; HAO Jie; GUO Xiaodong

    2007-01-01

    To evaluate the biocompatibility of poly(lactic acid/glycolic acid/ asparagic acid-copolyethylene glycol)(PLGA-[ASP-PEG]) tri-block copolymer in vitro, L929 fibroblast was co-cultured with the copolymer for cytotoxicity, hemolysis and pyrogen tests. And, compared with PLGA, the adhesiveness rate of the copolymer was calculated. The experimental results show that the toxicity gradation of the material was 0-1; L929 fibroblasts had a good cell morphology and proliferated rapidly on the surface of the material; hemolysis ratio was 3.08%; there was no pyrogen reaction. The adhesiveness of PLGA-[ASP-PEG] was better than that of the PLGA's(P<0.05). The results confirm that the PLGA-[ASP-PEG] has a good biocompatibility.

  19. Adaptive scapula bone remodeling computational simulation: Relevance to regenerative medicine

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Gulshan B., E-mail: gbsharma@ucalgary.ca [Emory University, Department of Radiology and Imaging Sciences, Spine and Orthopaedic Center, Atlanta, Georgia 30329 (United States); University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213 (United States); University of Calgary, Schulich School of Engineering, Department of Mechanical and Manufacturing Engineering, Calgary, Alberta T2N 1N4 (Canada); Robertson, Douglas D., E-mail: douglas.d.robertson@emory.edu [Emory University, Department of Radiology and Imaging Sciences, Spine and Orthopaedic Center, Atlanta, Georgia 30329 (United States); University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213 (United States)

    2013-07-01

    Shoulder arthroplasty success has been attributed to many factors including, bone quality, soft tissue balancing, surgeon experience, and implant design. Improved long-term success is primarily limited by glenoid implant loosening. Prosthesis design examines materials and shape and determines whether the design should withstand a lifetime of use. Finite element (FE) analyses have been extensively used to study stresses and strains produced in implants and bone. However, these static analyses only measure a moment in time and not the adaptive response to the altered environment produced by the therapeutic intervention. Computational analyses that integrate remodeling rules predict how bone will respond over time. Recent work has shown that subject-specific two- and three dimensional adaptive bone remodeling models are feasible and valid. Feasibility and validation were achieved computationally, simulating bone remodeling using an intact human scapula, initially resetting the scapular bone material properties to be uniform, numerically simulating sequential loading, and comparing the bone remodeling simulation results to the actual scapula’s material properties. Three-dimensional scapula FE bone model was created using volumetric computed tomography images. Muscle and joint load and boundary conditions were applied based on values reported in the literature. Internal bone remodeling was based on element strain-energy density. Initially, all bone elements were assigned a homogeneous density. All loads were applied for 10 iterations. After every iteration, each bone element’s remodeling stimulus was compared to its corresponding reference stimulus and its material properties modified. The simulation achieved convergence. At the end of the simulation the predicted and actual specimen bone apparent density were plotted and compared. Location of high and low predicted bone density was comparable to the actual specimen. High predicted bone density was greater than

  20. Research trends in biomimetic medical materials for tissue engineering: 3D bioprinting, surface modification, nano/micro-technology and clinical aspects in tissue engineering of cartilage and bone.

    Science.gov (United States)

    Chen, Cen; Bang, Sumi; Cho, Younghak; Lee, Sahnghoon; Lee, Inseop; Zhang, ShengMin; Noh, Insup

    2016-01-01

    This review discusses about biomimetic medical materials for tissue engineering of bone and cartilage, after previous scientific commentary of the invitation-based, Korea-China joint symposium on biomimetic medical materials, which was held in Seoul, Korea, from October 22 to 26, 2015. The contents of this review were evolved from the presentations of that symposium. Four topics of biomimetic medical materials were discussed from different research groups here: 1) 3D bioprinting medical materials, 2) nano/micro-technology, 3) surface modification of biomaterials for their interactions with cells and 4) clinical aspects of biomaterials for cartilage focusing on cells, scaffolds and cytokines.

  1. Alteration causes and processes in the stone material from the pavement in Baelo Claudia archeological site, Cadiz/Spain

    Directory of Open Access Journals (Sweden)

    Hoyos, M.

    1999-09-01

    Full Text Available A detailed study of the alteration causes in the stone material used in buildings and pavements from the ancient roman town of Baelo Claudia (Cádiz, South Spain was carried out to establish their degree of conservation. Slabs from the pavement of the Forum showed in general a high and irreversible degree of degradation. In order to palliate the action of processes of degradation in subaerial conditions, in this work some measures are proposed to try to preserve the slabs in better conditions.

    En este trabajo se muestran los resultados de un estudio detallado sobre el estado de conservación de los materiales pétreos usados en construcciones y pavimentos de la antigua ciudad romana de Baelo Claudia (Cádiz, Sur de España. En especial, las losas del pavimento del Foro romano mostraron, en general, un alto e irreversible grado de alteración. En este estudio, se proponen medidas correctoras para una mejor preservación de las losas, amortiguando la acción de los procesos de degradación propios de condiciones subaéreas.

  2. Teeth and bones: applications of surface science to dental materials and related biomaterials

    Science.gov (United States)

    Jones, F. H.

    2001-05-01

    Recent years have seen a considerable upsurge in publications concerning the surface structure and chemistry of materials with biological or biomedical applications. Within the body, gas-solid interactions become relatively less significant and solid-liquid or solid-solid interfaces dominate, providing new challenges for the surface scientist. The current paper aims to provide a timely review of the use of surface analysis and modification techniques within the biomaterials field. A broad overview of applications in a number of related areas is given with particular attention focusing on those materials commonly encountered in dentistry and oral or maxillofacial implantology. Several specific issues of current interest are discussed. The interaction between synthetic and natural solids, both in the oral environment and elsewhere in the body is important in terms of adhesion, related stresses and strains and ultimately the longevity of a dental restoration, biomedical implant, or indeed the surrounding tissue. Exposure to body fluids, of course, can also affect stability, leading to the degradation or corrosion of materials within the body. Whilst this could potentially be harmful, e.g., if cytotoxic elements are released, it may alternatively provide a route to the preferential release of beneficial substances. Furthermore, in some cases, the controlled disintegration of a biomaterial is desirable, allowing the removal of an implant, e.g., without the need for further surgery. The presence of cells in the immediate bioenvironment additionally complicates the situation. A considerable amount of current research activity is targeted at the development of coatings or surface treatments to encourage tissue growth. If this is to be achieved by stimulating enhanced cell productivity, determination of the relationship between cell function and surface composition is essential.

  3. Bonelike/PLGA hybrid materials for bone regeneration : preparation route and physicochemical characterisation

    OpenAIRE

    Oliveira, Joaquim M.; Miyazaki, T; Lopes, M A; Ohtsuki, C.; Santos,J.D.

    2005-01-01

    Bonelike R /PLGA hybrid materials have been developed using γ -MPS as silane-coupling agent between the inorganic and organic phases for controlled drug delivery applications. Silanization showed to be more effective when cyclohexane was used as a non-polar solvent (nP method) due to a chemical interaction between Bonelike R and the silane film, while by using a 95/5 (V/V) methanol/water as a polar solvent (P method), a much thinner film was achieved. Functional groups of PL...

  4. Intrinsic material property differences in bone tissue from patients suffering low-trauma osteoporotic fractures, compared to matched non-fracturing women.

    Science.gov (United States)

    Vennin, S; Desyatova, A; Turner, J A; Watson, P A; Lappe, J M; Recker, R R; Akhter, M P

    2017-04-01

    Osteoporotic (low-trauma) fractures are a significant public health problem. Over 50% of women over 50yrs. of age will suffer an osteoporotic fracture in their remaining lifetimes. While current therapies reduce skeletal fracture risk by maintaining or increasing bone density, additional information is needed that includes the intrinsic material strength properties of bone tissue to help develop better treatments, since measurements of bone density account for no more than ~50% of fracture risk. The hypothesis tested here is that postmenopausal women who have sustained osteoporotic fractures have reduced bone quality, as indicated with measures of intrinsic material properties compared to those who have not fractured. Transiliac biopsies (N=120) were collected from fracturing (N=60, Cases) and non-fracturing postmenopausal women (N=60, age- and BMD-matched Controls) to measure intrinsic material properties using the nano-indentation technique. Each biopsy specimen was embedded in epoxy resin and then ground, polished and used for the nano-indentation testing. After calibration, multiple indentations were made using quasi-static (hardness, modulus) and dynamic (storage and loss moduli) testing protocols. Multiple indentations allowed the median and variance to be computed for each type of measurement for each specimen. Cases were found to have significantly lower median values for cortical hardness and indentation modulus. In addition, cases showed significantly less within-specimen variability in cortical modulus, cortical hardness, cortical storage modulus and trabecular hardness, and more within-specimen variability in trabecular loss modulus. Multivariate modeling indicated the presence of significant independent mechanical effects of cortical loss modulus, along with variability of cortical storage modulus, cortical loss modulus, and trabecular hardness. These results suggest mechanical heterogeneity of bone tissue may contribute to fracture resistance

  5. Treatment of osteonecrosis of femoral head with BMSCs-seeded bio-derived bone materials combined with rhBMP-2 in rabbits

    Institute of Scientific and Technical Information of China (English)

    XIAO Zeng-ming; JIANG Hua; ZHAN Xin-li; WU Zhen-guo; ZHANG Xing-lin

    2008-01-01

    Objective: To evaluate the effect of autologous bone marrow mesenchymal stem cells (BMSCs) seeded bio-derived bone materials (BBM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in repairing defect of osteonecrosis of femoral head (ONFH). Methods: Early-stage osteonecrosis in the left hip was induced in 36 adult New Zealand white rabbits (provided by the Animal Center of Guangxi Medical University, Nanning, China) after core decompression and delivery of liquid nitrogen into the femoral head. Then the animals were divided into three groups according to the type of implants for bone repair: 12 rabbits with nothing (GroupⅠ, the blank control group), 12 with BBM combined with rhBMP-2 (Group Ⅱ), and 12 with BMSCs-seeded BBM combined with rhBMP-2 (Group Ⅲ). At 4, 8, and 12 weeks after surgery, X-ray of the femoral head of every 4 rabbits in each group was taken, and then they were killed and the femoral heads were collected at each time point, respectively. Gross observation was made on the femoral heads. After hematoxylin and eosin staining, Lane-sandhu scores of X-ray and bone densitometry were calculated and the histomorphometric measurements were made for the new bone trabeculae. Results: At 12 weeks after surgery, two femoral heads collapsed in GroupⅠ, but none in Group Ⅱor Group Ⅲ. X-ray examination showed that the femoral heads in Group Ⅰ had defect shadow or collapsed while those in Group Ⅱ had a low density and those in Group Ⅲ presented with a normal density. Histologically, the defects of femoral heads were primarily filled with no new bone but fibrous tissues in Group Ⅰ. In contrast, new bone regeneration and fibrous tissues occurred in Group Ⅱ and only new bone regeneration occurrd in Group Ⅲ. Lane-sandhu scores of X-ray, bone mineral density and rate of new bone in trabecular area in Group Ⅲ were higher signifIcantly than those of the other two groups. Conclusions: Our findings indicate a superior choice of

  6. Mimicking the nanostructure of bone matrix to regenerate bone

    Directory of Open Access Journals (Sweden)

    Robert Kane

    2013-11-01

    Full Text Available Key features of bone tissue structure and composition are capable of directing cellular behavior toward the generation of new bone tissue. Bone tissue, as well as materials derived from bone, have a long and successful history of use as bone grafting materials. Recent developments in design and processing of synthetic scaffolding systems has allowed the replication of the bone's desirable biological activity in easy to fabricate polymeric materials with nano-scale features exposed on the surface. The biological response to these new tissue-engineering scaffold materials oftentimes exceeds that seen on scaffolds produced using biological materials.

  7. Preparation and characterization of chitosan/nano-hydroxyapatite composite used as bone substitute materials

    Institute of Scientific and Technical Information of China (English)

    Zhang Li; Li Yubao; Zhou Gang; Wu Lan; Mu Yuanhua; Yang Zheng

    2007-01-01

    Chitosan/nano-hydroxyapatite composites with different weight ratios were prepared through a co-precipitation method using Ca(OH)2, H3PO4 and chitosan as starting materials. The properties of these composites were characterized by means of TEM, IR, XRD, TGA, bum-out tests and universal matertial testing machine. The results showed that the HA synthesized here was poorly crystalline carbonated nanometer crystals and dispersed uniformly in chitosan phase and there was no phase-separation between the two phases. The addition of n-HA resulted in a decrease of decomposing temperature of chitosan. Because of the interactions between chitosan and n-HA, the mechanical properties of these composites were improved, and the maximum value of the compressive strength was measured to be about 120MPa corresponding to the chitosan/n-HA composite with a weight ratio of 30/70.

  8. [Mandibular bone tissue regeneration after the introduction of the implantation system performed on the basis of carbon composite material].

    Science.gov (United States)

    Chetvertnykh, V A; Loginova, N P; Astashina, N B; Rogozhnikov, G I; Rapekta, S I

    2013-01-01

    The purpose of this study was to investigate the processes of regeneration of bone tissue after the introduction of new implant systems. In the experiment, performed on 10 male pigs of Landras breed aged 50-55 days and weighing 17-18.5 kg, the time course of histological changes was studied in the area of mandibular regeneration after the formation of tissue defect and the introduction of the implant of a proposed construction. Morphological analysis of the experimental results 90, 180 and 270 days after the operation demonstrated the process of reparative regeneration of damaged bone along implant-bone block boundaries. Bone repair proceeded through the stage of formation of the woven bone with its progressive substitution by the lamellar bone, with the maintenance of the shape, size and symmetry of the damaged organ.

  9. ZMW型环氧乙烷灭菌箱对异体骨材料灭菌效果的初步观察%Primary observation of the sterilizing effects of ZMW anprolene case on foreign bone materials

    Institute of Scientific and Technical Information of China (English)

    孙建华; 史晨辉; 董卫; 黄新玲; 王永明; 董金波; 刘维刚

    2002-01-01

    @@ Background: The foreign bone material of the same species was widely applied, while for the multiple manipulating processes, it got lots of chances to be infected, especially for the bone manufacturing, the pollution odds increased greatly, so the sterilizing process was most important. Objective: To observe the sterilizing effects of ZMW anprolene case on foreign bone materials to find a safe and economic disinfecting way. Unit:First attached hospital of the Shihezi medical university. Subject:The manipulating method of the foreign bone material of the same species: In clean environment., bone was got in 2 hours after death of the donor, soft tissue was removed and it was made to foreign bone material of 0.5 cm× 0.5 cm× 2 cm, it was washed with water and marinated till the water got clear, then washed with distilled water repeatedly, lipid was removed with 1:1 chloroform and methanol for 4 hours at room temperature, calcium was removed with 0.6 mol/L HCL for 4 hours at 4 ℃ , it was washed with distilled water till the pH was 6.5. The bone material after treating were divided into two groups, one was dried in common air dried to make wet one plantation material and the other one was dried in 37℃ roasting case to make dry bone plantation material. They were both put in double polyethylene bags and sealed with standard sealing machine, the weight was 5 g,

  10. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

    Full Text Available Bone grafting is the process by which bone is transferred from a source (donor to site (recipient. Due to trauma from accidents by speedy vehicles, falling down from height or gunshot injury particularly in human being, acquired or developmental diseases like rickets, congenital defects like abnormal bone development, wearing out because of age and overuse; lead to bone loss and to replace the loss we need the bone grafting. Osteogenesis, osteoinduction, osteoconduction, mechanical supports are the four basic mechanisms of bone graft. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. An ideal bone graft material is biologically inert, source of osteogenic, act as a mechanical support, readily available, easily adaptable in terms of size, shape, length and replaced by the host bone. Except blood, bone is grafted with greater frequency. Bone graft indicated for variety of orthopedic abnormalities, comminuted fractures, delayed unions, non-unions, arthrodesis and osteomyelitis. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. By adopting different procedure of graft preservation its antigenicity can be minimized. The concept of bone banking for obtaining bone grafts and implants is very useful for clinical application. Absolute stability require for successful incorporation. Ideal bone graft must possess osteogenic, osteoinductive and osteocon-ductive properties. Cancellous bone graft is superior to cortical bone graft. Usually autologous cancellous bone graft are used as fresh grafts where as allografts are employed as an alloimplant. None of the available type of bone grafts possesses all these properties therefore, a single type of graft cannot be recomm-ended for all types of orthopedic abnormalities. Bone grafts and implants can be selected as per clinical problems, the equipments available and preference of

  11. PMMA-based composite materials with reactive ceramic fillers: IV. Radiopacifying particles embedded in PMMA beads for acrylic bone cements.

    Science.gov (United States)

    Abboud, M; Casaubieilh, L; Morvan, F; Fontanille, M; Duguet, E

    2000-01-01

    New acrylic bone cements were prepared from alumina particles previously treated by 3-(trimethoxysilyl)propylmethacrylate (gamma-MPS) and embedded in poly(methylmethacrylate-co-ethylacrylate) beads with about 7 mol% of ethyl acrylate repeating units. The encapsulation was performed through a conventional suspension polymerization process. The influence of (i) the concentration of the dispersion stabilizer and (ii) the alumina content upon the shape, size, and size distribution of the acrylic beads was studied. Cements were prepared from each batch by hand-mixing alumina-filled acrylic beads with a liquid monomer mixture containing methyl methacrylate, n-butyl methacrylate, and N,N-dimethyl-p-toluidine. Benzoyl peroxide was previously added to the solid part. The powder-to-liquid ratio was equal to 2 for each formulation. Compressive strength of cured cement decreases with alumina content, whereas compressive modulus remains roughly constant. These results are in contradiction to those obtained for cements based on a mixture of gamma-MPS-treated alumina and unfilled acrylic beads. Nevertheless, they are interpreted in terms of alumina arrangement in the cement. In the first case, alumina particles contribute to the reinforcement of the dispersed acrylic phase, with poor benefits for the whole materials. In the second case, they allow the reinforcement of the continuous acrylic phase and, therefore, the cement's one.

  12. Alterações bucais e cuidados orais no paciente transplantado de medula óssea Oral alterations and oral care in bone marrow transplant patients

    Directory of Open Access Journals (Sweden)

    Ana C. Luiz

    2008-12-01

    Full Text Available Os cuidados gerais relativos ao paciente submetido ao transplante de medula óssea (TMO incluem avaliações odontológicas rotineiras, as quais devem estar inseridas em um contexto multiprofissional. A cavidade oral constitui um sítio propício a infecções com grande potencial de desenvolvimento de bacteremia, sendo que lesões infecciosas devem ser previamente tratadas e controladas pelo cirurgião-dentista. O objetivo desta revisão é discutir questões em destaque na literatura nacional e internacional referentes aos quadros inflamatórios e infecciosos orais de importância para o paciente transplantado de medula óssea, tanto os predisponentes a complicações durante o transplante, quanto os que ocorrem durante e após a terapia mielossupressora. Destaca-se na literatura a doença periodontal avançada, a qual constitui um quadro infeccioso crônico que deve ser evitado ou controlado durante o TMO, principalmente devido à presença de S. viridans. Os fatores de risco para mucosite oral (OM, doença do enxerto contra o hospedeiro (DECH e xerostomia ainda não estão definidos, principalmente para OM e DECH. São citadas na literatura alternativas promissoras de tratamento para OM, tais como crioterapia, administração de fatores de crescimento e laserterapia. O risco aumentado de cárie é controverso e, dentre as lesões fúngicas e virais, destacam-se as infecções orais e de orofaringe por Candida e pela família de herpesvírus, de importância clínica considerável. Em pacientes pediátricos são relevantes as alterações craniofaciais e dentárias, decorrentes principalmente da radioterapia.General care in bone marrow transplant (BMT patients includes routine dental evaluations, which must be included in a multi-professional context. The oral cavity is a site that favors infections with high potential for consequent bacteremia and so infectious lesions must be treated or controlled by the dentist. The aim of this review is

  13. The Use of Micro and Nano Particulate Fillers to Modify the Mechanical and Material Properties of Acrylic Bone Cement

    Science.gov (United States)

    Slane, Joshua A.

    Acrylic bone cement (polymethyl methacrylate) is widely used in total joint replacements to provide long-term fixation of implants. In essence, bone cement acts as a grout by filling in the voids left between the implant and the patient's bone, forming a mechanical interlock. While bone cement is considered the `gold standard' for implant fixation, issues such as mechanical failure of the cement mantle (aseptic loosening) and the development of prosthetic joint infection (PJI) still plague joint replacement procedures and often necessitate revision arthroplasty. In an effort to address these failures, various modifications are commonly made to bone cement such as mechanical reinforcement with particles/fibers and the addition of antibiotics to mitigate PJI. Despite these attempts, issues such as poor particle interfacial adhesion, inadequate drug release, and the development of multidrug resistant bacteria limit the effectiveness of bone cement modifications. Therefore, the overall goal of this work was to use micro and nanoparticles to enhance the properties of acrylic bone cement, with particular emphasis placed on improving the mechanical properties, cumulative antibiotic release, and antimicrobial properties. An acrylic bone cement (Palacos R) was modified with three types of particles in various loading ratios: mesoporous silica nanoparticles (for mechanical reinforcement), xylitol microparticles (for increased antibiotic release), and silver nanoparticles (as an antimicrobial agent). These particles were used as sole modifications, not in tandem with one another. The resulting cement composites were characterized using a variety of mechanical (macro to nano, fatigue, fracture, and dynamic), imaging, chemical, thermal, biological, and antimicrobial testing techniques. The primary outcomes of this dissertation demonstrate that: (1) mesoporous silica, as used in this work, is a poor reinforcement phase for acrylic bone cement, (2) xylitol can significantly

  14. Experimental study on the effects of artificial bone composite materials on bone formation%复合人工骨材料对骨形成影响的实验研究

    Institute of Scientific and Technical Information of China (English)

    李练兵; 马明福; 张其清; 侯志伟; 朱一剑; 张丹妍; 吕静; 赵乐天; 杨智曦; 朱明华

    2014-01-01

    探讨胶原/羟基磷灰石(hydroxyapatile-collagen,CHA )-骨形态发生蛋白(bone morphogenetic protein,BMP)复合材料的体外成骨效应,以及体内修复兔桡骨缺损的效果。方法采用体外细胞培养技术,将人胚成骨细胞分别与纯羟基磷灰石(hydroxyapatile,HA)、CHA、HA-BMP 和 CHA-BMP材料于体外联合培养,观察细胞的生长情况。测定细胞冻融中的细胞增殖率,及碱性磷酸酶(alkline phosphatase,ALP)、骨钙素(osteocalcin,OC)的分泌水平。小鼠股部肌袋内植入,评价其异位骨诱导能力。然后在兔桡骨缺损部位植入,术后2周、4周、8周、16周、24周观察新骨形成规律。结果胶原/羟基磷灰石-骨形态发生蛋白复合材料的细胞增殖率、ALP、OC 水平明显高于相应单一材料,异位诱导可见软骨及骨组织,ALP呈阳性。桡骨植入8周、16周时 X射线显示骨断端形成紧密的纤维连接,有少量骨痂形成,镜下可见大量成熟板层骨及骨髓组织填充,免疫组织化学(BMP、I 型胶原、骨胶原)均呈阳性反应,非 BMP复合材料未见骨或软骨形成。结论 CHA-BMP 复合材料有利于成骨细胞早期黏附、生长,小鼠异位骨诱导,加速兔缺损桡骨的新骨形成,从而促进骨愈合,是一种较理想的骨修复材料。%Objective To explore the osteogenic effect of collagen/hydroxyapatite(CHA)composite of bone morphogenetic protein (BMP)material in vitro and in repairing rabbit radius defect effect.Methods With the technique of cell culture in vitro,the human embryo osteoblast was cultured in vitro with HA,CHA,HA-BMP and CHA-BMP materials respectively and was observed the cell growth in the materials.The cell proliferation rate and secretion of ALP and OC were detected in cell frozen solution.The ability to induce ectopic bone was evaluated in the implant of mouse femoral muscle pouches.The laws of new bone formation were

  15. Bone Biopsy

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Bone Biopsy Bone biopsy uses a needle and imaging ... the limitations of Bone Biopsy? What is a Bone Biopsy? A bone biopsy is an image-guided ...

  16. Skeletal maturity leads to a reduction in the strain magnitudes induced within the bone: a murine tibia study.

    Science.gov (United States)

    Razi, Hajar; Birkhold, Annette I; Zaslansky, Paul; Weinkamer, Richard; Duda, Georg N; Willie, Bettina M; Checa, Sara

    2015-02-01

    Bone adapts to changes in the local mechanical environment (e.g. strains) through formation and resorption processes. However, the bone adaptation response is significantly reduced with increasing age. The mechanical strains induced within the bone by external loading are determined by bone morphology and tissue material properties. Although it is known that changes in bone mass, architecture and bone tissue quality occur with age, to what extent they contribute to the altered bone adaptation response remains to be determined. This study investigated alterations in strains induced in the tibia of different aged female C57Bl/6J mice (young, 10-week-old; adult, 26-week-old; and elderly, 78-week-old) subjected to in vivo compressive loading. Using a combined in vivo/in silico approach, the strains in the bones were assessed by both strain gauging and finite element modeling experiments. In cortical bone, strain magnitudes induced at the mid-diaphysis decreased by 20% from young to adult mice and by 15% from adult to elderly mice. In the cancellous bone (at the proximal metaphysis), induced strains were 70% higher in young compared with adult and elderly mice. Taking into account previous studies showing a reduced bone adaptation response to mechanical loading in adulthood, these results suggest that the diminished adaptive response is in part due to a reduction in the strains induced within the bone.

  17. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Bone Densitometry (DEXA) Bone densitometry, also called dual-energy ... limitations of DEXA Bone Densitometry? What is a Bone Density Scan (DEXA)? Bone density scanning, also called ...

  18. Effects of vitamin K on the morphometric and material properties of bone in the tibiae of growing rats.

    Science.gov (United States)

    Matsumoto, Takeshi; Miyakawa, Takushi; Yamamoto, Daiki

    2012-03-01

    Suboptimal vitamin K nutriture is evident during rapid growth. We aimed to determine whether vitamin K(2) (menaquinone-4 [MK-4]) supplementation is beneficial to bone structure and intrinsic bone tissue properties in growing rats. Male Wistar rats (5 weeks old) were assigned to either a control diet (n = 8) or an MK-4-supplemented diet (22 mg d(-1) kg(-1) body weight, n = 8). After a 9-week feeding period, we determined the serum concentration ratio of undercarboxylated osteocalcin to γ-carboxylated osteocalcin and the urinary deoxypyridinoline level. All rats were then euthanized, and their tibiae were analyzed by micro-computed tomography for trabecular architecture and synchrotron radiation micro-computed tomography for cortical pore structure and mineralization. Fourier transform infrared microspectroscopy and a nanoindentation test were performed on the cortical midlayers of the anterior and posterior cortices to assess bone tissue properties. Neither body weight nor tibia length differed significantly between the 2 groups. Dietary MK-4 supplementation decreased the ratio of undercarboxylated osteocalcin to γ-carboxylated osteocalcin but did not affect deoxypyridinoline, indicating a positive effect on bone formation but not bone resorption. Trabecular volume fraction and thickness were increased by MK-4 (P < .05). Neither the cortical pore structure nor mineralization was affected by MK-4. On the other hand, MK-4 increased mineral crystallinity, collagen maturity, and hardness in both the anterior and posterior cortices (P < .05). These data indicate the potential benefit of MK-4 supplementation during growth in terms of enhancing bone quality.

  19. Changes in chemical composition of bone matrix in ovariectomized (OVX) rats detected by Raman spectroscopy and multivariate analysis

    Science.gov (United States)

    Oshima, Yusuke; Iimura, Tadahiro; Saitou, Takashi; Imamura, Takeshi

    2015-02-01

    Osteoporosis is a major bone disease that connotes the risk of fragility fractures resulting from alterations to bone quantity and/or quality to mechanical competence. Bone strength arises from both bone quantity and quality. Assessment of bone quality and bone quantity is important for prediction of fracture risk. In spite of the two factors contribute to maintain the bone strength, only one factor, bone mineral density is used to determine the bone strength in the current diagnosis of osteoporosis. On the other hand, there is no practical method to measure chemical composition of bone tissue including hydroxyapatite and collagen non-invasively. Raman spectroscopy is a powerful technique to analyze chemical composition and material properties of bone matrix non-invasively. Here we demonstrated Raman spectroscopic analysis of the bone matrix in osteoporosis model rat. Ovariectomized (OVX) rat was made and the decalcified sections of tibias were analyzed by a Raman microscope. In the results, Raman bands of typical collagen appeared in the obtained spectra. Although the typical mineral bands at 960 cm-1 (Phosphate) was absent due to decalcified processing, we found that Raman peak intensities of amide I and C-C stretching bands were significantly different between OVX and sham-operated specimens. These differences on the Raman spectra were statistically compared by multivariate analyses, principal component analysis (PCA) and liner discrimination analysis (LDA). Our analyses suggest that amide I and C-C stretching bands can be related to stability of bone matrix which reflects bone quality.

  20. Date identification of the Zhouji materials during the period of King Xin--The chronology Solving method of oracle boneS and bronzes in the Shang and Zhou dynasties

    Institute of Scientific and Technical Information of China (English)

    LI; Yong(李勇)

    2002-01-01

    By identifying the dates of the Zhouji materials (one kind of oracle bone) during the period of King Xin (also called Zhou the last monarch in Shang Dynasty), this paper establishes a new "Direct Solving Method" (DSM) to solve the chronology problems in the Shang and Zhou dynasties. The mathematical models are more suitable for those materials with the Ganzhi (the Heavenly Stems and Earthly Branches, the Chinese ancient date recorded method being of the 60-day cycle, that the repetitive cycle is independent of any astronomical parameter, each day within this cycle has its own name and can also be expressed by the numbers from l to 60) record of the date, lunar month, and their year intervals and all of them are in history documents, oracle bones and bronze vessels. For example, taking the 12 Zhouji materials in the period of King Xin,we derive the two best results of the first year when Xin assumed the reins of government in probably 1063 BC or 1052 BC.

  1. Short-term bisphosphonate treatment reduces serum 25(OH) vitamin D3 and alters values of parathyroid hormone, pentosidine, and bone metabolic markers

    Science.gov (United States)

    Kamimura, Mikio; Uchiyama, Shigeharu; Nakamura, Yukio; Ikegami, Shota; Mukaiyama, Keijiro; Kato, Hiroyuki

    2017-01-01

    This study aimed to clarify the effects of short-term bisphosphonate (BP) administration in Japanese osteoporotic patients retrospectively. Daily minodronate (MIN) at 1 mg/day (MIN group) or weekly risedronate (RIS) at 17.5 mg/week (RIS group) was primarily prescribed for each patient. We analyzed the laboratory data of 35 cases (18 of MIN and 17 of RIS) before the start of treatment and at 4 months afterward. The changes in 25(OH)D3, whole parathyroid hormone (PTH), serum pentosidine, and the bone turnover markers urinary cross-linked N-telopeptide of type I collagen (NTX), serum tartrate-resistant acid phosphatase (TRACP)-5b, bone-specific alkaline phosphatase (BAP), and undercarboxylated osteocalcin were evaluated. Overall, serum 25(OH)D3 was significantly decreased from 21.8 to 18.4 ng/mL at 4 months, with a percent change of −14.7%. Whole PTH increased significantly from 23.4 to 30.0 pg/mL, with a percent change of 32.1%. Serum pentosidine rose from 0.0306 to 0.0337 μg/mL, with a percent change of 15.2%. In group comparisons, 25(OH)D3 and pentosidine showed comparable changes in both groups after 4 months of treatment, whereas whole PTH became significantly more increased in the MIN group. All bone turnover markers were significantly decreased at 4 months in both groups. Compared with the RIS group, the MIN group exhibited significantly larger value changes for urinary NTX, serum TRACP-5b, and BAP at the study end point. This study demonstrated that serum 25(OH)D3 became significantly decreased after only 4 months of BP treatment in Japanese osteoporotic patients and confirmed that MIN more strongly inhibited bone turnover as compared with RIS.

  2. Maternal protein restriction during pregnancy and lactation alters central leptin signalling, increases food intake, and decreases bone mass in 1 year old rat offspring.

    Science.gov (United States)

    Qasem, Rani J; Li, Jing; Tang, Hee Man; Pontiggia, Laura; D'mello, Anil P

    2016-04-01

    The effects of perinatal nutrition on offspring physiology have mostly been examined in young adult animals. Aging constitutes a risk factor for the progressive loss of metabolic flexibility and development of disease. Few studies have examined whether the phenotype programmed by perinatal nutrition persists in aging offspring. Persistence of detrimental phenotypes and their accumulative metabolic effects are important for disease causality. This study determined the effects of maternal protein restriction during pregnancy and lactation on food consumption, central leptin sensitivity, bone health, and susceptibility to high fat diet-induced adiposity in 1-year-old male offspring. Sprague-Dawley rats received either a control or a protein restricted diet throughout pregnancy and lactation and pups were weaned onto laboratory chow. One-year-old low protein (LP) offspring exhibited hyperphagia. The inability of an intraperitoneal (i.p.) leptin injection to reduce food intake indicated that the hyperphagia was mediated by decreased central leptin sensitivity. Hyperphagia was accompanied by lower body weight suggesting increased energy expenditure in LP offspring. Bone density and bone mineral content that are negatively regulated by leptin acting via the sympathetic nervous system (SNS), were decreased in LP offspring. LP offspring did not exhibit increased susceptibility to high fat diet induced metabolic effects or adiposity. The results presented here indicate that the programming effects of perinatal protein restriction are mediated by specific decreases in central leptin signalling to pathways involved in the regulation of food intake along with possible enhancement of different CNS leptin signalling pathways acting via the SNS to regulate bone mass and energy expenditure.

  3. Determinants of ovine compact bone viscoelastic properties: effects of architecture, mineralization, and remodeling.

    Science.gov (United States)

    Les, C M; Spence, C A; Vance, J L; Christopherson, G T; Patel, B; Turner, A S; Divine, G W; Fyhrie, D P

    2004-09-01

    Significant decreases in ovine compact bone viscoelastic properties (specifically, stress-rate sensitivity, and damping efficiency) are associated with three years of ovariectomy and are particularly evident at higher frequencies [Proc. Orthop. Res. Soc. 27 (2002) 89]. It is unclear what materials or architectural features of bone are responsible for either the viscoelastic properties themselves, or for the changes in those properties that were observed with estrogen depletion. In this study, we examined the relationship between these viscoelastic mechanical properties and features involving bone architecture (BV/TV), materials parameters (ash density, %mineralization), and histologic evidence of remodeling (%remodeled, cement line interface). The extent of mineralization was inversely proportional to the material's efficiency in damping stress oscillations. The damping characteristics of bone material from ovariectomized animals were significantly more sensitive to variation in mineralization than was bone from control animals. At low frequencies (6 Hz or less), increased histologic evidence of remodeling was positively correlated with increased damping efficiency. However, the dramatic decreases in stress-rate sensitivity that accompanied 3-year ovariectomy were seen throughout the bone structure and occurred even in areas with little or no secondary Haversian remodeling as well as in areas of complete remodeling. Taken together, these data suggest that, while the mineral component may modify the viscoelastic behavior of bone, the basic mechanism underlying bone viscoelastic behavior, and of the changes in that behavior with estrogen depletion, reside in a non-mineral component of the bone that can be significantly altered in the absence of secondary remodeling.

  4. A structural approach in the study of bones: fossil and burnt bones at nanosize scale

    Science.gov (United States)

    Piga, Giampaolo; Baró, Maria Dolors; Escobal, Irati Golvano; Gonçalves, David; Makhoul, Calil; Amarante, Ana; Malgosa, Assumpció; Enzo, Stefano; Garroni, Sebastiano

    2016-12-01

    We review the different factors affecting significantly mineral structure and composition of bones. Particularly, it is assessed that micro-nanostructural and chemical properties of skeleton bones change drastically during burning; the micro- and nanostructural changes attending those phases manifest themselves, amongst others, in observable alterations to the bones colour, morphology, microstructure, mechanical strength and crystallinity. Intense changes involving the structure and chemical composition of bones also occur during the fossilization process. Bioapatite material is contaminated by an heavy fluorination process which, on a long-time scale reduces sensibly the volume of the original unit cell, mainly the a-axis of the hexagonal P63/m space group. Moreover, the bioapatite suffers to a varying degree of extent by phase contamination from the nearby environment, to the point that rarely a fluorapatite single phase may be found in fossil bones here examined. TEM images supply precise and localized information, on apatite crystal shape and dimension, and on different processes that occur during thermal processes or fossilization of ancient bone, complementary to that given by X-ray diffraction and Attenuated Total Reflection Infrared spectroscopy. We are presenting a synthesis of XRD, ATR-IR and TEM results on the nanostructure of various modern, burned and palaeontological bones.

  5. Monitoring the Changes of Material Properties at Bone-Implant Interface during the Healing Process In Vivo: A Viscoelastic Investigation

    Science.gov (United States)

    Chen, Hsiang-Ho; Lai, Wei-Yi; Chee, Tze-Jian

    2017-01-01

    The aim of this study was to monitor the changes of viscoelastic properties at bone-implant interface via resonance frequency analysis (RFA) and the Periotest device during the healing process in an experimental rabbit model. Twenty-four dental implants were inserted into the femoral condyles of rabbits. The animals were sacrificed immediately after implant installation or on day 14, 28, or 56 after surgery. Viscoelastic properties at bone-implant interface were evaluated by measuring the implant stability quotient (ISQ) using RFA and by measuring the Periotest values (PTVs) using the Periotest device. The bone/implant specimens were evaluated histopathologically and histomorphometrically to determine the degree of osseointegration (BIC%). The BIC% values at different time points were then compared with the corresponding ISQ values and PTVs. The mean ISQ value increased gradually and reached 81 ± 1.7 on day 56, whereas the mean PTV decreased over time, finally reaching −0.7 ± 0.5 on day 56. Significant correlations were found between ISQ and BIC% (r = 0.701, p < 0.001), PTV and BIC% (r = −0.637, p < 0.05), and ISQ and PTV (r = −0.68, p < 0.05). These results show that there is a positive correlation between implant stability parameters and peri-implant-bone healing, indicating that the RFA and Periotest are useful for measuring changes of viscoelastic properties at bone-implant interface and are reliable for indirectly predicting the degree of osseointegration. PMID:28373978

  6. Stress distribution in fixed-partial prosthesis and peri-implant bone tissue with different framework materials and vertical misfit levels: a three-dimensional finite element analysis.

    Science.gov (United States)

    Bacchi, Ataís; Consani, Rafael L X; Mesquita, Marcelo F; dos Santos, Mateus B F

    2013-09-01

    The purpose of this study was to evaluate the influence of superstructure material and vertical misfits on the stresses created in an implant-supported partial prosthesis. A three-dimensional (3-D) finite element model was prepared based on common clinical data. The posterior part of a severely resorbed jaw with two osseointegrated implants at the second premolar and second molar regions was modeled using specific modeling software (SolidWorks 2010). Finite element models were created by importing the solid model into mechanical simulation software (ANSYS Workbench 11). The models were divided into groups according to the prosthesis framework material (type IV gold alloy, silver-palladium alloy, commercially pure titanium, cobalt-chromium alloy, or zirconia) and vertical misfit level (10 µm, 50 µm, and 100 µm) created at one implant-prosthesis interface. The gap of the vertical misfit was set to be closed and the stress values were measured in the framework, porcelain veneer, retention screw, and bone tissue. Stiffer materials led to higher stress concentration in the framework and increased stress values in the retention screw, while in the same circumstances, the porcelain veneer showed lower stress values, and there was no significant difference in stress in the peri-implant bone tissue. A considerable increase in stress concentration was observed in all the structures evaluated within the misfit amplification. The framework material influenced the stress concentration in the prosthetic structures and retention screw, but not that in bone tissue. All the structures were significantly influenced by the increase in the misfit levels.

  7. Short-term bisphosphonate treatment reduces serum 25(OH vitamin D3 and alters values of parathyroid hormone, pentosidine, and bone metabolic markers

    Directory of Open Access Journals (Sweden)

    Kamimura M

    2017-02-01

    Full Text Available Mikio Kamimura,1 Shigeharu Uchiyama,2 Yukio Nakamura,2,3 Shota Ikegami,2 Keijiro Mukaiyama,2 Hiroyuki Kato2 1Center for Osteoporosis and Spinal Disorders, Kamimura Orthopaedic Clinic, Matsumoto, Japan; 2Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto, Japan; 3Department of Orthopedic Surgery, Showa-Inan General Hospital, Komagane, Japan Abstract: This study aimed to clarify the effects of short-term bisphosphonate (BP administration in Japanese osteoporotic patients retrospectively. Daily minodronate (MIN at 1 mg/day (MIN group or weekly risedronate (RIS at 17.5 mg/week (RIS group was primarily prescribed for each patient. We analyzed the laboratory data of 35 cases (18 of MIN and 17 of RIS before the start of treatment and at 4 months afterward. The changes in 25(OHD3, whole parathyroid hormone (PTH, serum pentosidine, and the bone turnover markers urinary cross-linked N-telopeptide of type I collagen (NTX, serum tartrate-resistant acid phosphatase (TRACP-5b, bone-specific alkaline phosphatase (BAP, and undercarboxylated osteocalcin were evaluated. Overall, serum 25(OHD3 was significantly decreased from 21.8 to 18.4 ng/mL at 4 months, with a percent change of –14.7%. Whole PTH increased significantly from 23.4 to 30.0 pg/mL, with a percent change of 32.1%. Serum pentosidine rose from 0.0306 to 0.0337 µg/mL, with a percent change of 15.2%. In group comparisons, 25(OHD3 and pentosidine showed comparable changes in both groups after 4 months of treatment, whereas whole PTH became significantly more increased in the MIN group. All bone turnover markers were significantly decreased at 4 months in both groups. Compared with the RIS group, the MIN group exhibited significantly larger value changes for urinary NTX, serum TRACP-5b, and BAP at the study end point. This study demonstrated that serum 25(OHD3 became significantly decreased after only 4 months of BP treatment in Japanese osteoporotic patients and

  8. Bone within a bone

    Energy Technology Data Exchange (ETDEWEB)

    Williams, H.J.; Davies, A.M. E-mail: wendy.turner@roh.nhs.uk; Chapman, S

    2004-02-01

    The 'bone within a bone' appearance is a well-recognized radiological term with a variety of causes. It is important to recognize this appearance and also to be aware of the differential diagnosis. A number of common conditions infrequently cause this appearance. Other causes are rare and some remain primarily of historical interest, as they are no longer encountered in clinical practice. In this review we illustrate some of the conditions that can give the bone within a bone appearance and discuss the physiological and pathological aetiology of each where known.

  9. Bone morphogenetic protein-2 (BMP-2 and transforming growth factor-β1 (TGF-β1 alter connexin 43 phosphorylation in MC3T3-E1 Cells

    Directory of Open Access Journals (Sweden)

    Rudkin George H

    2001-07-01

    Full Text Available Abstract Background Bone morphogenetic proteins (BMPs and transforming growth factor-βs (TGF-βs are important regulators of bone repair and regeneration. BMP-2 and TGF-β1 have been shown to inhibit gap junctional intercellular communication (GJIC in MC3T3-E1 cells. Connexin 43 (Cx43 has been shown to mediate GJIC in osteoblasts and it is the predominant gap junctional protein expressed in these murine osteoblast-like cells. We examined the expression, phosphorylation, and subcellular localization of Cx43 after treatment with BMP-2 or TGF-β1 to investigate a possible mechanism for the inhibition of GJIC. Results Northern blot analysis revealed no detectable change in the expression of Cx43 mRNA. Western blot analysis demonstrated no significant change in the expression of total Cx43 protein. However, significantly higher ratios of unphosphorylated vs. phosphorylated forms of Cx43 were detected after BMP-2 or TGF-β1 treatment. Immunofluorescence and cell protein fractionation revealed no detectable change in the localization of Cx43 between the cytosol and plasma membrane. Conclusions BMP-2 and TGF-β1 do not alter expression of Cx43 at the mRNA or protein level. BMP-2 and TGF-β1 may inhibit GJIC by decreasing the phosphorylated form of Cx43 in MC3T3-E1 cells.

  10. In Vitro Expansion of Bone Marrow Derived Mesenchymal Stem Cells Alters DNA Double Strand Break Repair of Etoposide Induced DNA Damage

    Directory of Open Access Journals (Sweden)

    Ian Hare

    2016-01-01

    Full Text Available Mesenchymal stem cells (MSCs are of interest for use in diverse cellular therapies. Ex vivo expansion of MSCs intended for transplantation must result in generation of cells that maintain fidelity of critical functions. Previous investigations have identified genetic and phenotypic alterations of MSCs with in vitro passage, but little is known regarding how culturing influences the ability of MSCs to repair double strand DNA breaks (DSBs, the most severe of DNA lesions. To investigate the response to DSB stress with passage in vitro, primary human MSCs were exposed to etoposide (VP16 at various passages with subsequent evaluation of cellular damage responses and DNA repair. Passage number did not affect susceptibility to VP16 or the incidence and repair kinetics of DSBs. Nonhomologous end joining (NHEJ transcripts showed little alteration with VP16 exposure or passage; however, homologous recombination (HR transcripts were reduced following VP16 exposure with this decrease amplified as MSCs were passaged in vitro. Functional evaluations of NHEJ and HR showed that MSCs were unable to activate NHEJ repair following VP16 stress in cells after successive passage. These results indicate that ex vivo expansion of MSCs alters their ability to perform DSB repair, a necessary function for cells intended for transplantation.

  11. Evaluation of the inflammatory potential of implant materials in a mouse model by bioluminescent imaging of intravenously injected bone marrow cells.

    Science.gov (United States)

    Rais, Bushra; Köster, Mario; Rahim, Muhammad Imran; Pils, Marina; Seitz, Jan-Marten; Hauser, Hansjörg; Wirth, Dagmar; Mueller, Peter P

    2016-09-01

    To evaluate the inflammatory potential of implants a bioluminescent imaging assay was developed using luciferase-expressing bone marrow cells that were injected into the blood circulation of wild-type mice. After subcutaneous implantation of titanium discs as an example for a clinically established biocompatible material, the luminosity was modest. Similarly, low luminosity signals were generated by pure magnesium implants that were used to represent metallic alloys that are presently under investigation as novel degradable implant materials. Increased luminosity was observed in response to degradable polymeric PLGA implants. Surgical wounds induced a basic luminescent response even in the absence of an implant. However, the material-independent response to injury could be minimized using injectable microparticle suspensions. In parallel with the resorption of biodegradable microparticles, the signal induced by PLGA declined faster when compared to non-degradable polystyrene suspensions. By using an interferon type I inducible Mx2 promoter construct to drive luciferase gene expression, the highest luminosity was observed in response to bacteria, indicating that the system could also be employed to monitor implant infections. Overall, labeled bone marrow cells yielded specific, well-defined localized signals that correlated with the inflammatory responses to implants. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2149-2158, 2016.

  12. Bone scintiscanning updated.

    Science.gov (United States)

    Lentle, B C; Russell, A S; Percy, J S; Scott, J R; Jackson, F I

    1976-03-01

    Use of modern materials and methods has given bone scintiscanning a larger role in clinical medicine, The safety and ready availability of newer agents have led to its greater use in investigating both benign and malignant disease of bone and joint. Present evidence suggests that abnormal accumulation of 99mTc-polyphosphate and its analogues results from ionic deposition at crystal surfaces in immature bone, this process being facilitated by an increase in bone vascularity. There is, also, a component of matrix localization. These factors are in keeping with the concept that abnormal scintiscan sites represent areas of increased osteoblastic activity, although this may be an oversimplification. Increasing evidence shows that the bone scintiscan is more sensitive than conventional radiography in detecting focal disease of bone, and its ability to reflect the immediate status of bone further complements radiographic findings. The main limitation of this method relates to nonspecificity of the results obtained.

  13. 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.

  14. Wettability alteration: A comprehensive review of materials/methods and testing the selected ones on heavy-oil containing oil-wet systems.

    Science.gov (United States)

    Mohammed, Mohammedalmojtaba; Babadagli, Tayfun

    2015-06-01

    Changing the wetting state of materials is a growing field of research in many areas of engineering and science. In the oil industry, the term wettability alteration usually refers to the process of making the reservoir rock more water-wet. This is of particular importance in naturally hydrophobic carbonates, fractured formations, and heavy-oil systems. This shift in wettability enhances oil recovery in oil-wet and weakly water-wet reservoirs and eventually increases the ultimate oil recovery. For wettability alteration, two methods have been traditionally used: Thermal and chemical. Although many attempts have been made on reviewing the advancement of research in certain aspects of wettability, a comprehensive review of these techniques, especially in terms of the classification of the chemicals used, has been ignored. In this paper, we begin with this review and provide the past experience of wettability alteration in sandstone and carbonate reservoirs. More than 100 papers were reviewed extensively with an in-depth analysis of different methods suggested in literature. The areas of controversy and contradicted observations are discussed. The limitations and the applicability of each method were analyzed. Concerns on up-scaling laboratory findings to field scale are also addressed. The most promising potential methods are identified and their critical conditions highlighted. At the end, a selection of reviewed methods is validated experimentally for one of the most challenging cases: Extra heavy-oil and bitumen recovery from fractured-strongly-oil-wet carbonates. Berea sandstone (aged to be oil-wet) and Indiana limestone samples were saturated with heavy oil (3600cp). Next, the process was initiated by soaking the cores into solvent (heptane or diluent oil) and the oil recovery was estimated using refractive index measurements. Note that solvent was selected to dilute the oil and recover a considerable amount of oil as any chemical or thermal methods yielded

  15. Study of surface alterations of composite and ionomeric materials submitted to simulation of a high cariogenic challenge

    Directory of Open Access Journals (Sweden)

    VIEIRA Alexandre Rezende

    1999-01-01

    Full Text Available We evaluated the surface of composite resins and glass-ionomer cements in a situation of high cariogenic challenge. Based on seventy-five standard test specimens of one glass-ionomer cement (Chelon Fil - ESPE, one resin-modified glass-ionomer (Vitremer - 3M, two polyacid-modified composite (VariGlass and Dyract - Dentsply and one composite resin (Heliomolar - Vivadent, submitted to fourteen days of demineralization and remineralization cycling to simulate a high cariogenic challenge, the erosive aspects of the surface of the materials were assessed. All of the samples were evaluated by scanning electronic microscope and compared with another five test specimens of each material, prepared in the same way and serving as control. All of the materials studied suffered erosive action by the media, with different characteristics due to the different compositions, after being submitted to in vitro simulation of a high cariogenic challenge.

  16. Physical and chemical characterisation of crude meat and bone meal combustion residue: 'waste or raw material?'

    Energy Technology Data Exchange (ETDEWEB)

    Deydier, Eric [Laboratoire de Chimie Inorganique et Sante, Universite Paul Sabatier, IUT A, Avenue Georges Pompidou, 81100 Castres (France)]. E-mail: eric.deydier@iut-tlse3.fr; Guilet, Richard [Laboratoire de Chimie Inorganique et Sante, Universite Paul Sabatier, IUT A, Avenue Georges Pompidou, 81100 Castres (France); Sarda, Stephanie [Laboratoire de Chimie Inorganique et Sante, Universite Paul Sabatier, IUT A, Avenue Georges Pompidou, 81100 Castres (France); Sharrock, Patrick [LCBM, Universite Paul Sabatier, Avenue Georges Pompidou, 81100 Castres (France)

    2005-05-20

    As a result of the recent bovine spongiform encephalopathy (BSE) crisis in the European beef industry, the use of animal by-product is now severely controlled. Meat and bone meal (MBM) production can no longer be used to feed cattle and must be safely disposed of or transformed. Main disposal option is incineration, producing huge amounts of ashes the valorisation of which becomes a major concern. The aim of this work is to characterise MBM combustion residue in order to evaluate their physical and chemical properties to propose new valorisation avenues. The thermal behaviour of crude meat and bone meal was followed by thermogravimetric analysis (TGA) and (24 wt.%) inorganic residue was collected. The resulting ashes were characterised by powder X-ray diffraction (XRD), particle size distribution, specific surface area (BET), scanning electron microscopy (SEM) couple with energy disperse X-ray analysis (EDX). Elemental analysis revealed the presence of chloride, sodium, potassium, magnesium with high level of phosphate (56 wt.%) and calcium (31 wt.%), two major constituents of bone, mainly as a mixture of Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2} and Ca{sub 3}(PO{sub 4}){sub 2} phases. The impact of combustion temperature (from 550 to 1000 deg. C) on the constitution of ashes was followed by TGA, XRD and specific surface measurements. We observed a strong decrease of surface area for the ashes with crystallisation of calcium phosphates phases without major changes of chemical composition.

  17. Bone changes in leprosy

    Energy Technology Data Exchange (ETDEWEB)

    Mende, B.; Stein, G.; Kreysel, H.W.

    1985-02-01

    Bone lesions is a frequent organic manifestation in leprosy. Osseal destructions caused by granulomatous process induced by M. leprae are so-called specific lesions in contrast to non specific lesions based on nerval or arterial diseases. The specific osseal alterations are characterized by cystic brightenings in roentgenograms while non specific osseal changes show absorption to bone structure as akroosterolysis and osteoporosis. Typical radiologic findings in different stages of mutilation are demonstrated.

  18. Characterization of materials and alteration-degradation products of the Blessed Virgin Rosary altar in the Saint Dominic church in Ravenna: preliminary study for the restoration interventions

    Directory of Open Access Journals (Sweden)

    Cesare Fiori

    2003-02-01

    Full Text Available The construction of the Blessed Virgin Rosary altar in the Saint Dominic church (13th century in Ravenna occurred between 1723 and 1770. All the portions of the church are interested by intense degradation phenomena and, in particular, the altar preservation condition is worrying. The whole surface is covered by spots and deposits of various nature, efflorescences, swellings, detachments and lacunae. The main cause of damage is the humidity capillary climb. In a preliminary investigation, surveys and observations have been made in order to describe the materials and to evaluate the preservation condition. Then, the areas for sampling have been chosen for analyses and stratigraphies. The present work concerns the altar materials characterisation and the alteration – degradation products analyses: this is essential to plan the restoration interventions.

  19. Fiber-matrix interface studies on bioabsorbable composite materials for internal fixation of bone fractures. I. Raw material evaluation and measurement of fiber-matrix interfacial adhesion.

    Science.gov (United States)

    Slivka, M A; Chu, C C; Adisaputro, I A

    1997-09-15

    The objective of this study was to characterize and evaluate the performance of various fiber-matrix composite systems by studying the mechanical, thermal, and physical properties of the fiber and matrix components, and by studying the fiber-matrix interface adhesion strength using both microbond and fragmentation methods. The composites studies were poly(L-lactic acid) (PLLA) matrix reinforced with continuous fibers of either nonabsorbable AS4 carbon (C), absorbable calcium phosphate (CaP), poly(glycolic acid) (PGA), or chitin. Carbon and CaP single fibers had high Young's moduli and failed in a brittle manner. PGA and chitin single fibers had relatively lower Young's moduli and relatively higher ductility. Upon in vitro hydrolysis, CaP fibers retained 17% of their tensile strength and 39% of their Young's modulus after 12 h, PCA fibers retained 10% of their tensile strength and 52% of their Young's modulus after 16 days, and chitin fibers retained 87% of their tensile strength and 130% of their Young's modulus after 25 days. PLLA films had much lower strength and Young's moduli, but much higher ductility relative to the single fibers. Using the microbond method, the initial fiber-matrix interfacial shear strength (IFSS) of C/PLLA and CaP/PLLA microcomposites was 33.9 and 12.6 MPa, respectively. Upon in vitro hydrolysis, C/PLLA retained 49% of IFSS after 15 days and CaP/PLLA retained 46% of IFSS after 6 h. Using a fiber fragmentation method, the initial IFSS of C/PLLA, CaP/PLLA, and chitin/ PLLA was 22.2, 15.6, and 28.3 MPa, respectively. The performance of carbon fibers and C/PLLA composites was superior to the other fibers and fiber/PLLA systems, but the carbon fiber was nonabsorbable. CaP had the most suitable modulus of the absorbable fibers for fixing cortical bone fracture, but its rapid deterioration of mechanical properties and loss of IFSS limits its use. PGA and chitin fibers had suitable mechanical properties and their retention for fixing cancellous

  20. New bioactive hybrid material of nano-hydroxyapatite based on N-carboxyethylchitosan for bone tissue engineering

    Science.gov (United States)

    Lu, Yan; Zhu, Aiping; Wang, Wanpeng; Shi, Hongchan

    2010-09-01

    N-carboxyethylchitosan/nano-hydroxyapatite (NCECS/HA) composite films were fabricated and their potential applications in guiding bone regeneration were investigated in terms of their in vitro cellular activity. Fourier ransform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to investigate the structure and composition of the composite film. Field Emission scanning electron microscopy (FESEM) revealed that HA nanoparticles were dispersed homogeneously in NCECS matrix. The composite film has sufficient mechanical properties for tissue engineering scaffold. The composite film was found to have better cartilage cell adhesion and growth than pure NCECS film.

  1. Bone-derived mesenchymal stromal cells from HIV transgenic mice exhibit altered proliferation, differentiation capacity and paracrine functions along with impaired therapeutic potential in kidney injury

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Kang; Rai, Partab; Lan, Xiqian; Plagov, Andrei; Malhotra, Ashwani [Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Manhassett, NY (United States); Gupta, Sanjeev [Departments of Medicine and Pathology, Marion Bessin Liver Research Center, Diabetes Center, Cancer Center, Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Institute for Clinical and Translational Research, Albert Einstein College of Medicine, Bronx, NY (United States); Singhal, Pravin C., E-mail: psinghal@nshs.edu [Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Manhassett, NY (United States)

    2013-08-15

    Mesenchymal stem cells (MSCs) secrete paracrine factors that could be cytoprotective and serve roles in immunoregulation during tissue injury. Although MSCs express HIV receptors, and co-receptors, and are susceptible to HIV infection, whether HIV-1 may affect biological properties of MSCs needs more study. We evaluated cellular proliferation, differentiation and paracrine functions of MSCs isolated from compact bones of healthy control mice and Tg26 HIV-1 transgenic mice. The ability of MSCs to protect against cisplatin toxicity was studied in cultured renal tubular cells as well as in intact mice. We successfully isolated MSCs from healthy mice and Tg26 HIV-1 transgenic mice and found the latter expressed viral Nef, Vpu, NL4-3 and Vif genes. The proliferation and differentiation of Tg26 HIV-1 MSCs was inferior to MSCs from healthy mice. Moreover, transplantation of Tg26 HIV-1 MSCs less effectively improved outcomes compared with healthy MSCs in mice with acute kidney injury. Also, Tg26 HIV-1 MSCs secreted multiple cytokines, but at significantly lower levels than healthy MSCs, which resulted in failure of conditioned medium from these MSCs to protect cultured renal tubular cells from cisplatin toxicity. Therefore, HIV-1 had adverse biological effects on MSCs extending to their proliferation, differentiation, function, and therapeutic potential. These findings will help in advancing mechanistical insight in renal injury and repair in the setting of HIV-1 infection. -- Highlights: •MSCs isolated from HIV mice displayed HIV genes. •MSCs isolated from HIV mice exhibited attenuated growth and paracrine functions. •AKI mice with transplanted HIV-MSC displayed poor outcome. •HIV-1 MSC secreted multiple cytokines but at a lower level.

  2. Tribulus terrestris Alters the Expression of Growth Differentiation Factor 9 and Bone Morphogenetic Protein 15 in Rabbit Ovaries of Mothers and F1 Female Offspring.

    Science.gov (United States)

    Abadjieva, Desislava; Kistanova, Elena

    2016-01-01

    Although previous research has demonstrated the key role of the oocyte-derived factors, bone morphogenetic protein (BMP) 15 and growth differentiation factor (GDF) 9, in follicular development and ovulation, there is a lack of knowledge on the impact of external factors, which females are exposed to during folliculogenesis, on their expression. The present study investigated the effect of the aphrodisiac Tribulus terrestris on the GDF9 and BMP15 expression in the oocytes and cumulus cells at mRNA and protein levels during folliculogenesis in two generations of female rabbits. The experiment was conducted with 28 New Zealand rabbits. Only the diet of the experimental mothers group was supplemented with a dry extract of T. terrestris for the 45 days prior to insemination. The expression of BMP15 and GDF9 genes in the oocytes and cumulus cells of mothers and F1 female offspring was analyzed using real-time polymerase chain reaction (RT-PCR). The localization of the GDF9 and BMP15 proteins in the ovary tissues was determined by immunohistochemical analysis. The BMP15 and GDF9 transcripts were detected in the oocytes and cumulus cells of rabbits from all groups. T. terrestris caused a decrease in the BMP15 mRNA level in the oocytes and an increase in the cumulus cells. The GDF9 mRNA level increased significantly in both oocytes and cumulus cells. The downregulated expression of BMP15 in the treated mothers' oocytes was inherited in the F1 female offspring born to treated mothers. BMP15 and GDF9 show a clearly expressed sensitivity to the bioactive compounds of T. terrestris.

  3. Tribulus terrestris Alters the Expression of Growth Differentiation Factor 9 and Bone Morphogenetic Protein 15 in Rabbit Ovaries of Mothers and F1 Female Offspring.

    Directory of Open Access Journals (Sweden)

    Desislava Abadjieva

    Full Text Available Although previous research has demonstrated the key role of the oocyte-derived factors, bone morphogenetic protein (BMP 15 and growth differentiation factor (GDF 9, in follicular development and ovulation, there is a lack of knowledge on the impact of external factors, which females are exposed to during folliculogenesis, on their expression. The present study investigated the effect of the aphrodisiac Tribulus terrestris on the GDF9 and BMP15 expression in the oocytes and cumulus cells at mRNA and protein levels during folliculogenesis in two generations of female rabbits. The experiment was conducted with 28 New Zealand rabbits. Only the diet of the experimental mothers group was supplemented with a dry extract of T. terrestris for the 45 days prior to insemination. The expression of BMP15 and GDF9 genes in the oocytes and cumulus cells of mothers and F1 female offspring was analyzed using real-time polymerase chain reaction (RT-PCR. The localization of the GDF9 and BMP15 proteins in the ovary tissues was determined by immunohistochemical analysis. The BMP15 and GDF9 transcripts were detected in the oocytes and cumulus cells of rabbits from all groups. T. terrestris caused a decrease in the BMP15 mRNA level in the oocytes and an increase in the cumulus cells. The GDF9 mRNA level increased significantly in both oocytes and cumulus cells. The downregulated expression of BMP15 in the treated mothers' oocytes was inherited in the F1 female offspring born to treated mothers. BMP15 and GDF9 show a clearly expressed sensitivity to the bioactive compounds of T. terrestris.

  4. Optimization of a novel two-solution poly(methyl methacrylate) bone cement: Effect of composition on material properties and polymerization kinetics

    Science.gov (United States)

    Hasenwinkel, Julie Miller

    A novel two-solution poly(methyl methacrylate) bone cement was developed as an alternative to powder/liquid cements, which are used clinically for the fixation of total joint replacements. This material polymerizes via a free radical mechanism, initiated by the redox reaction of benzoyl peroxide (BPO) and N,N dimethyl-p-toluidine (DMPT). The two-solution concept is advantageous over powder/liquid formulations because it minimizes sources of porosity, produces a homogeneous microstructure, simplifies the mixing and delivery process, and reduces the dependence of material properties on surgical techniques. Experiments were performed to determine the effect of initiation chemistry on the material properties and polymerization kinetics of twelve cement compositions. Select material properties were also evaluated with respect to polymer/monomer ratio and initial polymer molecular weight. The results confirm the hypothesis that initiation chemistry affects material properties via the polymerization kinetics and resulting microstructural properties. The exotherm, setting time, flexural mechanical properties, fracture toughness, fatigue behavior, and residual monomer were evaluated, with respect to initiation chemistry. The flexural strength, modulus, and exotherm were maximized, while the residual monomer was minimized at a BPO:DMPT molar ratio of 1:1. High DMPT concentrations resulted in sub-optimal properties, with short setting times and reduced ductility, fracture toughness, and fatigue strength. Initial polymer molecular weight had no significant effect on the material properties. Polymer conversion and free radical concentration were measured by infrared (FTIR) and electron paramagnetic resonance (EPR) spectroscopy. These data were used to calculate the polymerization reaction rates and kinetic rate constants for each composition. Stoichiometric concentrations of BPO and DMPT maximized the radical concentration and conversion. The BPO and DMPT concentrations

  5. Bone Biochemistry on the International Space Station

    Science.gov (United States)

    Smith, Scott M.; Heer, Martina; Zwart, Sara R.

    2016-01-01

    Bone biochemical measures provide valuable insight into the nature and time course of microgravity effects on bone during space flight, where imaging technology cannot be employed. Increased bone resorption is a hallmark of space flight, while markers of bone formation are typically unchanged or decreased. Recent studies (after the deployment to ISS of the advanced resistive exercise device, ARED), have documented that astronauts with good nutritional intake (e.g., maintenance of body mass), good vitamin D status, and exercise maintained bone mineral density. These data are encouraging, but crewmembers exercising on the ARED do have alterations in bone biochemistry, specifically, bone resorption is still increased above preflight levels, but bone formation is also significantly increased. While this bone remodeling raises questions about the strength of the resulting bone, however documents beneficial effects of nutrition and exercise in counteracting bone loss of space flight.

  6. Alterations in bone morphogenetic protein 15, growth differentiation factor 9, and gene expression in granulosa cells in preovulatory follicles of dairy cows given porcine LH.

    Science.gov (United States)

    Behrouzi, Amir; Colazo, Marcos Germán; Ambrose, Divakar Justus

    2016-04-15

    In a previous work, using porcine LH (pLH) in lieu of GnRH for synchronizing ovulation in dairy cows improved pregnancy rates without increasing plasma progesterone concentrations after ovulation. The LH profile is known to remain elevated above basal concentrations (≥1 ng/mL) for up to 20 hours in pLH-treated cows compared to less than 6 hours in GnRH-treated cows. Because LH triggers a cascade of signaling networks in the preovulatory follicle to promote final maturation and support oocyte competence, we hypothesized that dissimilar LH profiles will differentially regulate the intrafollicular factors and expression of downstream genes associated with improved oocyte competence. Specific objectives were to determine differences in the abundance of oocyte-secreted factors in the preovulatory follicular fluid and target genes in granulosa cells associated with oocyte competence, in response to exogenous porcine LH or GnRH-induced endogenous bovine LH exposure, in dairy cows. Follicular contents were aspirated by a transvaginal ultrasound-guided procedure from the preovulatory follicle of cyclic, nonlactating Holstein cows 21 ± 1 hour after administration of either pLH (25-mg) or GnRH (100-μg). Mature forms of bone morphogenetic protein 15, growth differentiation factor 9, and transforming growth factorβ1 were approximately 2-fold more abundant in pLH-treated cows which were exposed to an extended, low LH profile, than in GnRH-treated cows that had a short, high LH profile. The relative abundance of messenger RNA for cyclooxygenase-2, LH receptor, and progesterone receptor in granulosa cells, was about two-, eight-, and two-fold higher, respectively, in cows subjected to pLH than GnRH treatment. We infer that the improved pregnancy rate after pLH-induced ovulation reported previously, occurred through greater activation of intrafollicular transforming growth factor-β1 superfamily members, as these proteins promote cumulus expansion and oocyte competence.

  7. Bone Markers

    Science.gov (United States)

    ... markers may be seen in conditions such as: Osteoporosis Paget disease Cancer that has spread to the bone (metastatic bone disease) Hyperparathyroidism Hyperthyroidism Osteomalacia in adults and rickets in children—lack of bone mineralization, ...

  8. Bone scan

    Science.gov (United States)

    ... legs, or spine fractures) Diagnose a bone infection (osteomyelitis) Diagnose or determine the cause of bone pain, ... 2015:chap 43. Read More Broken bone Metabolism Osteomyelitis Review Date 12/10/2015 Updated by: Jatin ...

  9. Bone Cancer

    Science.gov (United States)

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

  10. Bone Diseases

    Science.gov (United States)

    Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly ... childhood and your teens, your body adds new bone faster than it removes old bone. After about ...

  11. Nonspecific iodine accumulation in surgical suture material mimicking follicular thyroid cancer bone metastasis in (131)I scintigraphy.

    Science.gov (United States)

    Winkens, Thomas; Nietzsche, Sandor; Gottschaldt, Michael; Freesmeyer, Martin

    2014-02-01

    A 23-year-old man with follicular thyroid carcinoma and cervical lymph node metastases showed a clear I focus on the skull after radioiodine therapy; therefore, an osseous metastasis was suspected. I and MRI fusion suggested the I focus to be adjacent to an epicranial suture from an early childhood trepanation for epidural hematoma. Radio-guided surgery found dark brown material to be the source of the radiation and successfully removed the material. Subsequent electron microscopy revealed a thread within the dark brown material, suggesting suture material as the cause of I accumulation.

  12. Pseudoanaplastic tumors of bone

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Won-Jong [Uijongbu St. Mary Hospital, The Catholic University of Korea, Department of Orthopaedic Surgery, Gyunggido, 480-821 (Korea); Mirra, Joseph M. [Orthopaedic Hospital, Orthopedic Oncology, Los Angeles, California (United States)

    2004-11-01

    To discuss the concept of pseudoanaplastic tumors of bone, which pathologically show hyperchromatism and marked pleomorphism with quite enlarged, pleomorphic nuclei, but with no to extremely rare, typical mitoses, and to propose guidelines for their diagnosis. From a database of 4,262 bone tumors covering from 1971 to 2001, 15 cases of pseudoanaplastic bone tumors (0.35% of total) were retrieved for clinical, radiographic and pathologic review. Postoperative follow-up after surgical treatment was at least 3 years and a maximum of 7 years. There were eight male and seven female patients. Their ages ranged from 10 to 64 years with average of 29.7 years. Pathologic diagnoses of pseudoanaplastic variants of benign bone tumors included: osteoblastoma (4 cases), giant cell tumor (4 cases), chondromyxoid fibroma (3 cases), fibrous dysplasia (2 cases), fibrous cortical defect (1 case) and aneurysmal bone cyst (1 case). Radiography of all cases showed features of a benign bone lesion. Six cases, one case each of osteoblastoma, fibrous dysplasia, aneurysmal bone cyst, chondromyxoid fibroma, giant cell tumor and osteoblastoma, were initially misdiagnosed as osteosarcoma. The remaining cases were referred for a second opinion to rule out sarcoma. Despite the presence of significant cytologic aberrations, none of our cases showed malignant behavior following simple curettage or removal of bony lesions. Our observation justifies the concept of pseudoanaplasia in some benign bone tumors as in benign soft tissue tumors, especially in their late evolutionary stage when bizarre cytologic alterations strongly mimic a sarcoma. (orig.)

  13. Guided bone regeneration using autogenous tooth bone graft in implant therapy: case series.

    Science.gov (United States)

    Kim, Young-Kyun; Kim, Su-Gwan; Bae, Ji-Hyun; Um, In-Woong; Oh, Ji-Su; Jeong, Kyung-In

    2014-04-01

    Recently, techniques have been reported that involve the preparation of extracted teeth from patients used as particulated bone graft materials for bone graft purposes. For implant placement and bone graft, autogenous teeth bone graft materials were used in 15 patients, and clinically excellent results were obtained. In histological examination, favorable bony healing by osteoconduction was observed.

  14. The study of bone repair effect of recombinant human bone morphogenetic protein-2 combined with artificial bone substitute materials in alveolar defect around the dental implant%骨形态发生蛋白2复合人工骨替代材料修复犬种植体周骨缺损的研究

    Institute of Scientific and Technical Information of China (English)

    张敬阳; 黄翠

    2014-01-01

    Objective To evaluate the bone repair capacity of β-tricalciumphosphate (β-TCP) or Bio-Oss combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in Beagle dogs.Methods Ten healthy adult Beagle dogs were used in this study.The mandibular premolars of the dogs were extracted firstly.Three months later,dental implants were placed in the mandibular,and a 5 mm× 4 mm× 3 mm bone defect area was prepared on the buccal side of each implant.The bone defect areas were filled with β-TCP,rhBMP-2/β-TCP compound,Bio-Oss or rhBMP-2/Bio-Oss compound respectively.The bone defect areas were filled nothing as the blank.The dogs were sacrificed after 4 or 12 weeks.Samples were prepared for the gross observation,X-ray analysis and histomorphology analysis.Results The new bone formation was observed in all experiment groups.After 4 weeks,the bone density of materials combined with rhBMP-2 groups [(36.70 ± 1.73) % and (38.50 ± 1.83) %] were higher than the raw materials groups [(30.50 ± 1.81)% and (31.48 ± 1.86)%].After 12 weeks,the bone density of materials combined with rhBMP-2 groups [(52.84 ± 1.85) % and (54.85 ± 1.87) %] were also higher than the raw materials groups [(43.65 ± 1.81) % and (44.94 ± 1.88) %].And new bone formation rate of the materials combined with rhBMP-2 groups were higher than the raw materials groups at each evaluation time.Conclusion rhBMP-2 can promote the bone regeneration activity of the artificial bone substitute materials effectively.%目的 观察重组人骨形态发生蛋白-2(rhBMP-2)复合β-磷酸三钙(β-TCP)及无机牛骨(Bio-Oss)对骨缺损修复能力的影响.方法 拔除10条Beagle犬下颌前磨牙,3个月骨质愈合后预备种植窝并制备5 mm×4 mm×3 mm骨缺损区,植入种植体,并分别在骨缺损区填入β-TCP、rhBMP-2/β-TCP复合物、Bio-Oss或rhBMP-2/Bio-Oss复合物;空白对照组不充填.术后4、12周处死犬,行大体观察、X线观察和组织形态

  15. PMMA-based composite materials with reactive ceramic fillers: part III: radiopacifying particle-reinforced bone cements.

    Science.gov (United States)

    Abboud, M; Vol, S; Duguet, E; Fontanille, M

    2000-05-01

    New acrylic bone cements were prepared from alumina particles previously treated by 3-(trimethoxysilyl)propylmethacrylate (gamma-MPS), able to act both as radiopacifying and reinforcing agents. The present study deals with the handling characteristics and the compressive behavior of such cements. The influence of the particles morphology, their surface-modification by gamma-MPS bonding agent, their concentration in the cement, the powder-to-liquid ratio and the benzoyl peroxide concentration are reported. The role of grafted gamma-MPS molecules as coupling agent was confirmed. For several formulations, compressive strength and modulus reached 150 MPa and 3400 MPa respectively. Limitations in the use of such formulations are also comprehensively discussed.

  16. Novel Approaches to Bone Grafting: Porosity, Bone Morphogenetic Proteins, Stem Cells, and the Periosteum

    OpenAIRE

    Petrochenko, Peter; Narayan, Roger J.

    2010-01-01

    The disadvantages involving the use of a patient’s own bone as graft material have led surgeons to search for alternative materials. In this review, several characteristics of a successful bone graft material are discussed. In addition, novel synthetic materials and natural bone graft materials are being considered. Various factors can determine the success of a bone graft substitute. For example, design considerations such as porosity, pore shape, and interconnection play significant roles i...

  17. Bone-Forming Capabilities of a Newly Developed NanoHA Composite Alloplast Infused with Collagen: A Pilot Study in the Sheep Mandible

    Directory of Open Access Journals (Sweden)

    Charles Marin

    2013-01-01

    Full Text Available Lateral or vertical bone augmentation has always been a challenge, since the site is exposed to constant pressure from the soft tissue, and blood supply only exists from the donor site. Although, for such clinical cases, onlay grafting with autogenous bone is commonly selected, the invasiveness of the secondary surgical site and the relatively fast resorption rate have been reported as a drawback, which motivated the investigation of alternative approaches. This study evaluated the bone-forming capability of a novel nanoHA alloplast infused with collagen graft material made from biodegradable polylactic acid/polyglycolic acid versus a control graft material with the same synthesized alloplast without the nanoHA component and collagen infiltration. The status of newly formed bone and the resorption of the graft material were evaluated at 6 weeks in vivo histologically and three dimensionally by means of 3D microcomputed tomography. The histologic observation showed that newly formed bone ingrowth and internal resorption of the block were observed for the experimental blocks, whereas for the control blocks less bone ingrowth occurred along with lower resorption rate of the block material. The three-dimensional observation indicated that the experimental block maintained the external geometry, but at the same time successfully altered the graft material into bone. It is suggested that the combination of numerous factors contributed to the bone ingrowth and the novel development could be an alternative bone grafting choice.

  18. 复合α-TCP透磷灰石骨水泥材料的生物相容性研究%Biocompatibility of α-TCP brushite bone cement material

    Institute of Scientific and Technical Information of China (English)

    马建敏; 杨洪; 王凯; 刘璨; 赵慧娟

    2012-01-01

    目的:观察复合α-TCP透磷灰石骨水泥的生物相容性,为该复合骨水泥的临床应用提供动物组织学实验依据.方法:在β-TCP+ MCPM骨水泥的基础上添加α-TCP,得到一种改进型透磷灰石骨水泥.以传统的透磷灰石骨水泥为对照组,对其进行体外溶血试验、热源试验、急性毒性试验、皮肤过敏试验、肌内植入试验.结果:α-TCP透磷灰石骨水泥的溶血率<5%,无热源性、无毒性、无皮肤过敏,植入肌肉后无明显炎症反应.结论:α-TCP的透磷灰石骨水泥具有良好的生物相容性和安全性,可作为体内骨替换材料.%AIM: To investigate the biocompatibility of α-TCP brushite bone cement. METHOD; a-TCP was introduced to β-TCP + MCPM bone cement to obtain α-TCP brashite bone cement. The material was evaluated by hemulysis test, pyrogen test, acute toxicity test, skin allergy test and muscle implant test. The bioeompatibility of α-TCP brushite bone cement was compared with traditional brushite bone cement. RESULTS: The hemolysis rate of α-TCP brushite bone cement was below 5 percent. No pyrogenic, no toxic, no skin allergic, and no obvious inflammatory reaction were observs. CONCLUSION: The α-TCP brushite bone cement shows excellent biocompatibilily and safety, tence can be used in vivo as a bone substitute material.

  19. CT assisted biomimetic artificial bone des

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-gang; ZHANG Chao-zong; GUO Zhi-ping; TIAN Jie-mo

    2001-01-01

    @@ In the recent years, bioceramic materials have been widely used in the clinics. They are mainly fabricated as the substitution of human hard tissue, such as artificial bone and false tooth. As a medical implant, those that have similar structure to human bone have better biocompatibility and osteoinductional property. So it is necessary to design bone model close to human bone.

  20. Examination of Bone Marrow Mesenchymal Stem Cells Seeded onto Poly(3-hydroxybutyrate-co-3-hydroxybutyrate Biological Materials for Myocardial Patch

    Directory of Open Access Journals (Sweden)

    Junsheng Mu

    2014-03-01

    Full Text Available The implantation of the Bone Marrow Mesenchymal Stem Cells (BMSCs into the heart has been reported to be effective for the treatment of myocardial infarction; however, the methods most suitable for supporting stem cell growth in a myocardial patch, still remain unknown. We used a new polymer material composed of poly(3-hydroxybutyrate-co-3-hydroxybutyrate [P(3HB-co-3HB] co-cultured with BMSCs to create a myocardial patch. The BMSCs were obtained from healthy male BSL-C57 mice. The cells were treated with 5-azacytidine to investigate their differentiation into cardiomyocytes. The cells were seeded for 24 hours onto the P(3HB-co-3HB biological material films (n=8. Cell-biomaterial constructs were fixed and analyzed using different methods. BMSCs were CD34-, CD45-, CD90+ (low and CD73+. The cells were stained with anti-cardiac troponin T (cTnT and anti-connexin 43 (CX43 antibodies after 5-azacytidine treatment. Scanning electron microscopy revealed that the morphology of the BMSC was normal and that cell numbers were more abundant on the P(3HB-co-3HB material surfaces. The growth curve of the BMSCs on the biomaterial patches showed the P(3HB-co-3HB material enhanced good stem cell growth. Owing to its excellent biocompatibility and biodegradability properties, in particular its porosity, the P(3HB-co-3HB is hailed as an optimal material to support myocardial cell growth and to create a myocardial patch in patients with myocardial infarction.

  1. The effect of perfusion culture on proliferation and differentiation of human mesenchymal stem cells on biocorrodible bone replacement material

    Energy Technology Data Exchange (ETDEWEB)

    Farack, J., E-mail: jana.farack@tu-dresden.de [Technische Universitaet Dresden, Max Bergmann Center of Biomaterials, Budapester Str. 27, D-01069 Dresden (Germany); Wolf-Brandstetter, C. [Technische Universitaet Dresden, Max Bergmann Center of Biomaterials, Budapester Str. 27, D-01069 Dresden (Germany); Glorius, S.; Nies, B. [InnoTERE GmbH, Tatzberg 47-49, D-01307 Dresden (Germany); Standke, G. [Fraunhofer Institute for Ceramic Technologies and Systems (IKTS), Winterbergstr. 28, D-01277 Dresden (Germany); Quadbeck, P. [Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM), Winterbergstr. 28, D-01277 Dresden (Germany); Worch, H.; Scharnweber, D. [Technische Universitaet Dresden, Max Bergmann Center of Biomaterials, Budapester Str. 27, D-01069 Dresden (Germany)

    2011-12-15

    Biocorrodible iron foams were coated with different calcium phosphate phases (CPP) to obtain a bioactive surface and controlled degradation. Further adhesion, proliferation and differentiation of SaOs-2 and human mesenchymal stem cells were investigated under both static and dynamic culture conditions. Hydroxyapatite (HA; [Ca{sub 10}(PO{sub 4}){sub 6}OH{sub 2}]) coated foams released 500 {mu}g/g iron per day for Dulbecco's modified eagle medium (DMEM) and 250 {mu}g/g iron per day for McCoys, the unmodified reference 1000 {mu}g/g iron per day for DMEM and 500 {mu}g/g iron per day for McCoys, while no corrosion could be detected on brushite (CaHPO{sub 4}) coated foams. Using a perfusion culture system with conditions closer to the in vivo situation, cells proliferated and differentiated on iron foams coated with either brushite or HA while in static cell culture cells could proliferate only on Fe-brushite. We conclude that the degradation behaviour of biocorrodible iron foams can be varied by different calcium phosphate coatings, offering opportunities for design of novel bone implants. Further studies will focus on the influence of different modifications of iron foams on the expression of oxidative stress enzymes. Additional information about in vivo reactions and remodelling behaviour are expected from testing in implantation studies.

  2. Curcumin-functionalized silk materials for enhancing adipogenic differentiation of bone marrow-derived human mesenchymal stem cells.

    Science.gov (United States)

    Li, Chunmei; Luo, Tingting; Zheng, Zhaozhu; Murphy, Amanda R; Wang, Xiaoqin; Kaplan, David L

    2015-01-01

    Curcumin, a natural phenolic compound derived from the plant Curcuma longa, was physically entrapped and stabilized in silk hydrogel films, and its influence on human bone marrow-derived mesenchymal stem cells (hBMSC) was assessed related to adipogenic differentiation. The presence of curcumin significantly reduced the silk gelation time and changed the porous morphology of gel matrix, but did not change the formation of the silk beta-sheet structure. Based on spectrofluorimetric analysis, curcumin most likely interacted with hydrophobic residues in silk, interacting with the beta-sheet domains formed in the hydrogels. The antioxidant activity of silk film-associated curcumin remained functional over at least one month in both the dry and hydrated state. Negligible curcumin was released from silk hydrogel films over 48 h incubation in aqueous solution. For hBMSC cultured on silk films containing more than 0.25 mg ml(-1) curcumin, cell proliferation was inhibited, while adipogenesis was significantly promoted based on transcripts as well as Oil Red O staining. When hBMSC were cultured in media containing free curcumin, both proliferation and adipogenesis of hBMSC were inhibited when curcumin concentrations exceeded 5 μM, which is more than 1000 times higher than the level of curcumin released from the films in aqueous solution. Thus, silk film-associated curcumin exhibited different effects on hBMSC proliferation and differentiation compared with curcumin in solution.

  3. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    Full Text Available BACKGROUND: Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth. MATERIALS AND METHODS: The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant-bone interface was also investigated by push-out tests. RESULTS: The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony

  4. Relleno de cavidades óseas en cirugía maxilofacial con materiales aloplásticos Bone cavity filling with alloplastic material in maxillofacial surgery

    Directory of Open Access Journals (Sweden)

    S. Ochandiano Caicoya

    2007-02-01

    spontánea y en esos casos tienen utilidad tanto el hueso autólogo como los biomateriales y las membranas de regeneración.Two types of defects are differentiated in bone regeneration studies. Those that lack a capacity for spontaneous regeneration during the entire life of the individual (critical size defect and those that do have this capacity (non-critical size defect, providing the adequate conditions are found such as blood clot stability, space-maintaining and mechanical rest (the guided bone regeneration concept. In this controversy, bony defects of the maxillary sinus and the residual cavities after cyst removal are revised. Both are non-critical size defects that conserve several walls. Many authors used to conclude that for sinus elevation, using autologous bone in the graft material was always necessary, either on its own or mixed differently with biomaterials in proportions that were not defined, 50:50, 20:80 etc. Clinical evidence, which has also been reflected in the literature over recent years, contradicts this conclusion and it has been stated that biomaterials on their own in the maxillary sinuses achieve results that are comparable to those achieved with autologous bone, providing the ossification period is increased. We review new studies that even dispute the need for using any type of graft at all in order to achieve new bone formation within the maxillary sinus. The results in the residual cavities of bony defects after cyst removal, if various walls can be conserved, are even more conclusive. The best treatment for these defects is direct closure of the mucosa and waiting for the spontaneous regeneration of the defect. The use of autologous bone is unnecessary and, if we introduce biomaterials, we still do not achieve better biomechanical behavior of the residual bone. Ossification is delayed and the number of complications increases. Only in total thickness defects will the use of membranes be of any benefit. The defects that have lost various walls

  5. Quantifying Changes in the Spatial Structure of Trabecular Bone

    CERN Document Server

    Marwan, Norbert; Felsenberg, Dieter; Saparin, Peter; Kurths, Jürgen

    2010-01-01

    We apply recently introduced measures of complexity for the structural quantfication of distal tibial bone. For the first time, we are able to investigate the temporal structural alteration of trabecular bone. Based on four patients, we show how bone may alter due to temporal immobilisation.

  6. Predicting the elastic properties of selective laser sintered PCL/β-TCP bone scaffold materials using computational modelling.

    Science.gov (United States)

    Doyle, Heather; Lohfeld, Stefan; McHugh, Peter

    2014-03-01

    This study assesses the ability of finite element (FE) models to capture the mechanical behaviour of sintered orthopaedic scaffold materials. Individual scaffold struts were fabricated from a 50:50 wt% poly-ε-caprolactone (PCL)/β-tricalcium phosphate (β-TCP) blend, using selective laser sintering. The tensile elastic modulus of single struts was determined experimentally. High resolution FE models of single struts were generated from micro-CT scans (28.8 μm resolution) and an effective strut elastic modulus was calculated from tensile loading simulations. Three material assignment methods were employed: (1) homogeneous PCL elastic constants, (2) composite PCL/β-TCP elastic constants based on rule of mixtures, and (3) heterogeneous distribution of micromechanically-determined elastic constants. In comparison with experimental results, the use of homogeneous PCL properties gave a good estimate of strut modulus; however it is not sufficiently representative of the real material as it neglects the β-TCP phase. The rule of mixtures method significantly overestimated strut modulus, while there was no significant difference between strut modulus evaluated using the micromechanically-determined elastic constants and experimentally evaluated strut modulus. These results indicate that the multi-scale approach of linking micromechanical modelling of the sintered scaffold material with macroscale modelling gives an accurate prediction of the mechanical behaviour of the sintered structure.

  7. Pathophysiology of chronic kidney disease-mineral and bone disorder.

    Science.gov (United States)

    Mac Way, Fabrice; Lessard, Myriam; Lafage-Proust, Marie-Hélène

    2012-12-01

    Chronic kidney disease (CKD) alters the metabolism of several minerals, thereby inducing bone lesions and vessel-wall calcifications that can cause functional impairments and excess mortality. The histological bone abnormalities seen in CKD, known as renal osteodystrophy, consist of alterations in the bone turnover rate, which may be increased (osteitis fibrosa [OF]) or severely decreased (adynamic bone disease [AD]); abnormal mineralization (osteomalacia [OM]), and bone loss. Secondary hyperparathyroidism is related to early phosphate accumulation (responsible for FGF23 overproduction by bone tissue), decreased calcitriol production by the kidneys, and hypocalcemia. Secondary hyperparathyroidism is associated with OF. Other factors that affect bone include acidosis, chronic inflammation, nutritional deficiencies, and iatrogenic complications.

  8. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... of DXA Bone Densitometry? What is a Bone Density Scan (DXA)? Bone density scanning, also called dual-energy x-ray absorptiometry ( ... is today's established standard for measuring bone mineral density (BMD). An x-ray (radiograph) is a noninvasive ...

  9. Mechanical and physicochemical properties of xenogeneic bone scaffold materials A comparative study%猪骨支架材料与人骨支架材料的理化性能及力学特征

    Institute of Scientific and Technical Information of China (English)

    李晋; 曲戎梅; 戴景兴; 周志涛; 原林

    2008-01-01

    BACKGROUND: The core of bone tissue engineering is to construct a scaffold that is similar to human bone tissue structure and features.OBJECTIVE: To compare pathochemical and mechanical characteristics between pig and human bone scaffold materials.DESIGN, TIME AND SETTING: Contrast study was performed at Clinical Anatomy Institute, South Medical University; Guangdong Province Key Laboratory of Tissue Construction and Detection from March to December 2006.MATERIALS: Four fresh health adult human cadavers were provided by South Medical University, Guangzhou Red Cross Society, and the relatives knew the fact. Ultra low temperature freezing 6-month iliac bones of 6 adult swines were also used in this study.METHODS: Pig iliac and healthy adults iliac bones were obtained to remove soft tissue, curettage periosteum and bone marrow. Bone sawing machine was used to cut cancellous bone into smaller bone sections around 5 mm×5 mm×40 mm, which underwent ultrasonic cleaning, H2O2 and alcohol soaking, freeze drying and radiation treatment; finally, xenogeneic bone scaffold and allogeneic bone scaffold were obtained.MAIN OUTCOME MEASURES: Xenogeneic bone scaffold material and human allograft bone scaffold were observed with scanning electron microscopy to compare porosity, contents of protein content, calcium and phosphorus, and mechanical properties.RESULTS: Xenogeneic bone scaffold and allogeneic bone scaffold both had intrinsical bone trabecula, trabecular spaces and bone cavity system. Both of them had unabridged natural three dimensional network structure. The 3D supporting frames of them were complete. The xenogeneic bone scaffold had more spaces than allogeneic bone scaffold. The size of both scaffolds was approximation, about 400 μm. The interval porosity of xenogeneic bone scaffold was higher than the allogeneic bone scaffold (P0.05), and there was no significant difference in Young's modulus of xenogeneic bone scaffold and allogeneic bone scaffold (P>0.05).CONCLUSION

  10. (238)U/(235)U isotope ratios of crustal material, rivers and products of hydrothermal alteration: new insights on the oceanic U isotope mass balance.

    Science.gov (United States)

    Noordmann, Janine; Weyer, Stefan; Georg, R Bastian; Jöns, Svenja; Sharma, Mukul

    2016-01-01

    In this study, the U isotope composition, n((238)U)/n((235)U), of major components of the upper continental crust, including granitic rocks of different age and post-Archaean shales, as well as that of rivers (the major U source to the oceans) was investigated. Furthermore, U isotope fractionation during the removal of U at mid-ocean ridges, an important sink for U from the oceans, was investigated by the analyses of hydrothermal water samples (including low- and high-temperature fluids), low-temperature altered basalts and calcium carbonate veins. All analysed rock samples from the continental crust fall into a limited range of δ(238)U between -0.45 and -0.21 ‰ (relative to NBL CRM 112-A), with an average of -0.30 ± 0.15 ‰ (2 SD, N = 11). Despite differences in catchment lithologies, all major rivers define a relatively narrow range between -0.31 and -0.13 ‰, with a weighted mean isotope composition of -0.27 ‰, which is indistinguishable from the estimate for the upper continental crust (-0.30 ‰). Only some tributary rivers from the Swiss Alps display a slightly larger range in δ(238)U (-0.29 to +0.01 ‰) and lower U concentrations (0.87-3.08 nmol/kg) compared to the investigated major rivers (5.19-11.69 nmol/kg). These findings indicate that only minor net U isotope fractionation occurs during weathering and transport of material from the continental crust to the oceans. Altered basalts display moderately enriched U concentrations (by a factor of 3-18) compared to those typically observed for normal mid-ocean ridge basalts. These, and carbonate veins within altered basalts, show large U isotope fractionation towards both heavy and light U isotope compositions (ranging from -0.63 to +0.27 ‰). Hydrothermal water samples display low U concentrations (0.3-1 nmol/kg) and only limited variations in their U isotope composition (-0.43 ± 0.25 ‰) around the seawater value. Nevertheless, two of the investigated fluids display

  11. Bone marrow aspiration

    Science.gov (United States)

    Iliac crest tap; Sternal tap; Leukemia - bone marrow aspiration; Aplastic anemia - bone marrow aspiration; Myelodysplastic syndrome - bone marrow aspiration; Thrombocytopenia - bone marrow aspiration; Myelofibrosis - bone marrow aspiration

  12. Visualization and quantification of heterogeneous diffusion rates in granodiorite samples by X-ray absorption imaging. Diffusion within gouge materials, altered rim and intact rock matrix

    Energy Technology Data Exchange (ETDEWEB)

    Altman, S.J.; Tidwell, V.C. [Sandia National Laboratories, Albuquerque, NM (United States); Uchida, M. [Japan Nuclear Cycle Development Inst., Ibaraki (Japan)

    2001-08-01

    Matrix diffusion is one of the most important contaminant migration retardation processes in crystalline rocks. Performance assessment calculations in various countries assume that only the area of the fracture surface where advection is active provides access to the rock matrix. However, accessibility to the matrix could be significantly enhanced with diffusion into stagnant zones, fracture fillings, and through an alteration rim in the matrix. Laboratory visualization experiments were conducted on granodiorite samples to investigate and quantify diffusion rates within different zones of a Cretaceous granodiorite. Samples were collected from the Kamaishi experimental site in the northern part of the main island of Japan. Diffusion of iodine out of the sample is visualized and rates are measured using x-ray absorption imaging. X-ray images allow for measurements of relative iodine concentration and relative iodine mass as a function of time and two-dimensional space at a sub-millimeter spatial resolution. In addition, two-dimensional heterogeneous porosity fields (at the same resolution as the relative concentration fields) are measured. This imaging technique allows for a greater understanding of the spatial variability of diffusion rates than can be accomplished with standard bulk measurements. It was found that diffusion rates were fastest in partially gouge-filled fractures. Diffusion rates in the recrystallized calcite-based fracture-filling material were up to an order of magnitude lower than in gouge-filled fractures. Diffusion in altered matrix around the fractures was over an order of magnitude lower than that in the gouge-filled fractures. Healed fractures did not appear to have different diffusion rates than the unaltered matrix.

  13. Hyperspectral surface materials map of quadrangles 3666 and 3766, Balkh (219), Mazar-e Sharif (220), Qarqin (213), and Hazara Toghai (214) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  14. Hyperspectral surface materials map of quadrangles 3360 and 3460, Kawir-e Naizar (413), Kohe-Mahmudo-Esmailjan (414), Kol-e Namaksar (407), and Ghoriyan (408) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  15. Hyperspectral surface materials map of quadrangles 2962 and 3062, Gawdezereh (615), Galachah (616), Chahar Burjak (609), and Khan Neshin (610) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Hoefen, Todd M.; Kokaly, Raymond F.; King, Trude V.V.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  16. Hyperspectral surface materials map of quadrangles 3668 and 3768, Baghlan (221), Taluqan (222), Imam Sahib (215), and Rustaq (216) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  17. Hyperspectral surface materials map of quadrangles 3664 and 3764, Char Shengo (123), Shibirghan (124), Jalajin (117), and Kham-Ab (118) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  18. Hyperspectral surface materials map of quadrangle 3260, Dasht-e-Chah-e-Mazar (419) and Anar Darah (420) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  19. Matrix Vesicle Enzyme Activity and Phospholipid Content in Endosteal Bone Following Implantation of Osseointegrating and Non-Osseointegrating Implant Materials.

    Science.gov (United States)

    1991-11-01

    matrix vesicles (Schwartz et al., 1990a; Boyan et al., 1988; Peress et al., 1974) and is intimately associated with mineral formation as the principle...directly related to the process of primary mineral formation in tissues adjacent to osseointegrating and non- integrating materials. Of particular...Evans, L. 1981. Mechanisms of mineral formation by matrix vesicles. In: Matrix Vesicles, Proc. 3rd Int. Conf. Matrix Vesicles. Ascenci, A., Bonucci, D

  20. Implants of polyanionic collagen matrix in bone defects of ovariectomized rats.

    Science.gov (United States)

    Cunha, Marcelo Rodrigues; Santos, Arnaldo Rodrigues; Goissis, Gilberto; Genari, Selma C

    2008-03-01

    In recent years, there has been a great interest in the development of biomaterials that could be used in the repair of bone defects. Collagen matrix (CM) has the advantage that it can be modified chemically to improve its mechanical properties. The aim of the present study was to evaluate the effect of three-dimensional membranes of native or anionic (submitted to alkaline treatment for 48 or 96 h) collagen matrix on the consolidation of osteoporosis bone fractures resulting from the gonadal hormone alterations caused by ovariectomy in rats subjected to hormone replacement therapy. The animals received the implants 4 months after ovariectomy and were sacrificed 8 weeks after implantation of the membranes into 4-mm wide bone defects created in the distal third of the femur with a surgical bur. Macroscopic analysis revealed the absence of pathological alterations in the implanted areas, suggesting that the material was biocompatible. Microscopic analysis showed a lower amount of bone ingrowth in the areas receiving the native membrane compared to the bone defects filled with the anionic membranes. In ovariectomized animals receiving anionic membranes, a delay in bone regeneration was observed mainly in animals not subjected to hormone replacement therapy. We conclude that anionic membranes treated with alkaline solution for 48 and 96 h presented better results in terms of bone ingrowth.

  1. Exploring gamma radiation effect on exoelectron emission properties of bone

    Energy Technology Data Exchange (ETDEWEB)

    Zakaria, M.; Dekhtyar, Y.; Bogucharska, T.; Noskov, V. [Riga Technical Univ., Biomedical Engineering and Nanotechnology Institute (Latvia)

    2006-07-01

    Gamma radiation is used for radiation therapy to treat carcinogenic diseases including bone cancer. Ionising radiation kills carcinogenic calls. However, there are side effects of the gamma radiation on the bone surface electron structure. One of the effects is in the form of altering electron density of states of bone that, with time, influences biomedical reactions on bone life condition. (authors)

  2. Evaluation of a novel nanocrystalline hydroxyapatite paste Ostim® in comparison to Alpha-BSM® - more bone ingrowth inside the implanted material with Ostim® compared to Alpha BSM®

    Directory of Open Access Journals (Sweden)

    Palazzi Xavier

    2009-12-01

    Full Text Available Abstract Background The purpose of this study was to evaluate the performance a newly developed nanocrystalline hydroxyapatite, OSTIM® following functional implantation in femoral sites in thirty-eight sheep for 1, 2 or 3 months. Ostim® 35 was compared to an established calcium phosphate, Alpha BSM®. Methods Biomechanical testing, μ-CT analysis, histological and histomorphological analyses were conducted to compare the treatments including evaluation of bone regeneration level, material degradation, implant biomechanical characteristics. Results The micro-computed tomography (μCT analysis and macroscopic observations showed that Ostim® seemed to diffuse easily particularly when the defects were created in a cancellous bone area. Alpha BSM® remained in the defect. The performance of Ostim was good in terms of mechanical properties that were similar to Alpha BSM® and the histological analysis showed that the bone regeneration was better with Ostim® than with Alpha BSM®. The histomorphometric analysis confirmed the qualitative analysis and showed more bone ingrowth inside the implanted material with Ostim® when compared to Alpha BSM ® at all time points. Conclusions The successful bone healing with osseous consolidation verifies the importance of the nanocrystalline hydroxyapatite in the treatment of metaphyseal osseous volume defects in the metaphyseal spongiosa.

  3. Rapidly growing Brtl/+ mouse model of osteogenesis imperfecta improves bone mass and strength with sclerostin antibody treatment.

    Science.gov (United States)

    Sinder, Benjamin P; Salemi, Joseph D; Ominsky, Michael S; Caird, Michelle S; Marini, Joan C; Kozloff, Kenneth M

    2015-02-01

    Osteogenesis imperfecta (OI) is a heritable collagen-related bone dysplasia, characterized by brittle bones with increased fracture risk that presents most severely in children. Anti-resorptive bisphosphonates are frequently used to treat pediatric OI and controlled clinical trials have shown that bisphosphonate therapy improves vertebral outcomes but has little benefit on long bone fracture rate. New treatments which increase bone mass throughout the pediatric OI skeleton would be beneficial. Sclerostin antibody (Scl-Ab) is a potential candidate anabolic therapy for pediatric OI and functions by stimulating osteoblastic bone formation via the canonical Wnt signaling pathway. To explore the effect of Scl-Ab on the rapidly growing OI skeleton, we treated rapidly growing 3week old Brtl/+ mice, harboring a typical heterozygous OI-causing Gly→Cys substitution on col1a1, for 5weeks with Scl-Ab. Scl-Ab had anabolic effects in Brtl/+ and led to new cortical bone formation and increased cortical bone mass. This anabolic action resulted in improved mechanical strength to WT Veh levels without altering the underlying brittle nature of the material. While Scl-Ab was anabolic in trabecular bone of the distal femur in both genotypes, the effect was less strong in these rapidly growing Brtl/+ mice compared to WT. In conclusion, Scl-Ab was able to stimulate bone formation in a rapidly growing Brtl/+ murine model of OI, and represents a potential new therapy to improve bone mass and reduce fracture risk in pediatric OI.

  4. New generation poly(ε-caprolactone)/gel-derived bioactive glass composites for bone tissue engineering: Part I. Material properties.

    Science.gov (United States)

    Dziadek, Michal; Menaszek, Elzbieta; Zagrajczuk, Barbara; Pawlik, Justyna; Cholewa-Kowalska, Katarzyna

    2015-11-01

    Poly(ε-caprolactone) (PCL) based composite films containing 12 and 21vol.% bioactive glass (SBG) microparticles were prepared by solvent casting method. Two gel-derived SBGs of SiO2-CaO-P2O5 system differing in SiO2 and CaO contents were applied (mol%): S2: 80SiO2, 16CaO, 4P2O5 and A2: 40SiO2, 54CaO, 6P2O5. The surfaces of the films in contact with Petri dish and exposed to the gas phase during casting were denoted as GS and AS, respectively. Both surfaces of films were characterised in terms of their morphology, micro- and nano-topography as well as wettability. Also mechanical properties (tensile strength, Young's modulus) and PCL matrix crystallinity (degree of crystallinity, crystal size) were evaluated. Degradation behaviour was examined by incubation of materials in UHQ-water at 37°C for 56weeks. The crystallinity, melting temperature and mass loss of incubated materials and pH changes of water were monitored. Furthermore, proliferation of MG-63 osteoblastic cells by direct contact and cytotoxic effect of obtained materials were investigated. Results showed that opposite surfaces of the same polymer and composite films differ in studied surface parameters. The addition of SBG particles into PCL matrix improves nano- and micro-roughness of both surfaces, enhances the hydrophilicity of GS surfaces (~67° for 21A2-PCL compared to ~78° for pure PCL) and also makes AS surface more hydrophobic (~94° for 21S2-PCL compared to ~86° for pure PCL). The nucleation density of PCL was increased with increasing content of SBG particles, which results in the large number of fine spherulites on composite AS surfaces observed using polarized optical (POM), scanning electron (SEM), and atomic force (AFM) microscopies. Higher content of SBG particles causes a notable increase of Young's modulus (from 0.38GPa for pure PCL, 0.90GPa for 12A2-PCL to 1.31GPa for 21A2-PCL), which also depends on SBG chemical composition. After 56-week degradation test, considerably higher

  5. New generation poly(ε-caprolactone)/gel-derived bioactive glass composites for bone tissue engineering: Part I. Material properties

    Energy Technology Data Exchange (ETDEWEB)

    Dziadek, Michal, E-mail: dziadek@agh.edu.pl [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland); Menaszek, Elzbieta, E-mail: elzbieta.menaszek@uj.edu.pl [Jagiellonian University, Collegium Medicum, Department of Cytobiology, 9 Medyczna St., 30-688 Krakow (Poland); Zagrajczuk, Barbara, E-mail: b.zagrajczuk@gmail.com [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland); Pawlik, Justyna, E-mail: pawlikj@agh.edu.pl [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland); Cholewa-Kowalska, Katarzyna, E-mail: cholewa@agh.edu.pl [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland)

    2015-11-01

    Poly(ε-caprolactone) (PCL) based composite films containing 12 and 21 vol.% bioactive glass (SBG) microparticles were prepared by solvent casting method. Two gel-derived SBGs of SiO{sub 2}–CaO–P{sub 2}O{sub 5} system differing in SiO{sub 2} and CaO contents were applied (mol%): S2: 80SiO{sub 2}, 16CaO, 4P{sub 2}O{sub 5} and A2: 40SiO{sub 2}, 54CaO, 6P{sub 2}O{sub 5}. The surfaces of the films in contact with Petri dish and exposed to the gas phase during casting were denoted as GS and AS, respectively. Both surfaces of films were characterised in terms of their morphology, micro- and nano-topography as well as wettability. Also mechanical properties (tensile strength, Young's modulus) and PCL matrix crystallinity (degree of crystallinity, crystal size) were evaluated. Degradation behaviour was examined by incubation of materials in UHQ-water at 37 °C for 56 weeks. The crystallinity, melting temperature and mass loss of incubated materials and pH changes of water were monitored. Furthermore, proliferation of MG-63 osteoblastic cells by direct contact and cytotoxic effect of obtained materials were investigated. Results showed that opposite surfaces of the same polymer and composite films differ in studied surface parameters. The addition of SBG particles into PCL matrix improves nano- and micro-roughness of both surfaces, enhances the hydrophilicity of GS surfaces (~ 67° for 21A2-PCL compared to ~ 78° for pure PCL) and also makes AS surface more hydrophobic (~ 94° for 21S2-PCL compared to ~ 86° for pure PCL). The nucleation density of PCL was increased with increasing content of SBG particles, which results in the large number of fine spherulites on composite AS surfaces observed using polarized optical (POM), scanning electron (SEM), and atomic force (AFM) microscopies. Higher content of SBG particles causes a notable increase of Young's modulus (from 0.38 GPa for pure PCL, 0.90 GPa for 12A2-PCL to 1.31 GPa for 21A2-PCL), which also depends on

  6. Comparative study of three types of polymer materials co-cultured with bone marrow mesenchymal stem cells for use as a myocardial patch in cardiomyocyte regeneration.

    Science.gov (United States)

    Niu, Hongxing; Mu, Junsheng; Zhang, Jianqun; Hu, Ping; Bo, Ping; Wang, Yan

    2013-06-01

    The purpose of this study was to investigate the most suitable polymer material for supporting stem cell growth as a myocardial patch. After cell isolation and expansion of mouse bone marrow mesenchymal stem cells (BMSC), the cells were induced to differentiate into cardiomyocytes with 5-azacytidine to determine their differentiation potential. BMSCs were also seeded onto three types of polymer material film, including polyurethane (PU), 3-hydroxybutyrate-co-4-hydroxybutyrate [P(3HB-co-4HB)], and polypropylene carbonate (PPC). The results revealed that cell numbers were more abundant on both the PU and P(3HB-co-4HB) material surfaces. Conversely, the surface of PPC was smooth with only cell lysate debris observed. The average cell counts were as follows: 143.78 ± 38.38 (PU group), 159.50 ± 33.07 [P(3HB-co-4HB) group], and 1.40 ± 0.70 (PPC group). There was no statistically significant difference in cell numbers between the PU and P(3HB-co-4HB) groups. A statistically significant difference was identified between the PPC group and both the PU (P1) and P(3HB-co-4HB) groups (P2). Polymer biomaterial patches composed of PU and P(3HB-co-4HB) permit good stem cell growth. P(3HB-co-4HB) has the potential for development as a clinical alternative to current treatment methods for the regeneration of cardiomyocytes in patients with myocardial infarction.

  7. Quantitative exposure assessment for the combustion of meat and bone meal derived from specified risk material in the context of BSE in Ireland.

    Science.gov (United States)

    Cummins, E J; Grace, P M; Fry, D J; McDonnell, K P; Colgan, S F; Ward, S M

    2002-11-01

    The probability and severity of an adverse event can be analyzed by quantitative exposure assessment (QEA). This methodology was applied to model the human health risks associated with the combustion of specified risk material (SRM) derived meat and bone meal (MBM) in a combustion facility. The identification of MBM and SRM as significant factors in the spread of bovine spongiform encephalopathy (BSE) has resulted in restrictions on their use and movement, and this has led to a requirement for alternative end-uses for these products. A stochastic (Latin Hypercube sampling) simulation model was developed to assess the exposure and hence the risks associated with the use of SRM-derived MBM in a combustion facility. The model simulates the potential infectivity pathways that SRM-derived MBM follows, including its production from animals potentially infected with sub-clinical BSE and subsequent processing of the material with segregation and heat treatments. A failure probability was included to take account of sub-optimal operating conditions. Two scenarios, reflecting the infectivity risk in different animal tissues as defined by the European Commission's scientific steering committee (SSC), were performed with 100,000 iterations of the model. Model results showed that the societal exposure to humans resulting from the combustion of SRM-derived MBM is extremely small (mean values ranging from 7.57 x 10(-6) ID50/year to 8.38 x 10(-5) ID50/year). The resulting societal risks are significantly less than the background societal risk of approximately 2.5 cases of sporadic CJD in Ireland each year. A sensitivity analysis revealed that the species barrier had a large impact on exposure calculations and hence should be the focus of further scientific investigation to reduce our uncertainty about this parameter. The model predicts that material spillage into untreated effluent represents the biggest risk to humans, indicating that efforts for risk mitigation should be focused

  8. The Hydrothermal System at Home Plate in Gusev Crater, Mars: Formation of High Silica Material by Acid-Sulfate Alteration of Basalt

    Science.gov (United States)

    Morris, R. V.; Ming, D. W.; Gellert, R.; Yen, A.; Clark, B. C.; Gnaff, T. G.; Arvidson, R. E.; Squyres, S. W.

    2008-01-01

    The Alpha Particle X-ray Spectrometer (APXS) instrument on the Mars Exploration Rover (MER) Spirit measured three targets on or adjacent to Home Plate in Gusev Crater that have unusually high SiO2 concentrations (68% to 91%), unusually low FeO concentrations (1% to 7%, with total Fe as FeO), and unusually high TiO2/FeO ratios (0.2 to 1.2 by weight) [1]. Two targets (Kenosha Comets and Lefty Ganote) are located on high albedo soil (Gertrude Weise) that was exposed by the rover wheels, and one target is a float rock called Fuzzy Smith. Kenosha Comets has the highest SiO2 concentration, lowest FeO concentration, and highest TiO2/FeO ratio. Mineralogical evidence from the MER Miniature Thermal Emission Spectrometer (Mini-TES) suggests that the SiO2 is present as amorphous (noncrystalline) SiO2 at Gertrude Weise and nearby targets [2,3]. Mini-TES data were not acquired for Fuzzy Smith. Home Plate is considered to have an explosive volcanic origin, resulting when basaltic magma came into contact with ground water or ice [4]. Within 50 m to 1 km of Home Plate are sulfate rich soil deposits (Paso Robles class soils with 22-35% SO3) which are considered to be probable fumarolic and/or hydrothermal deposits associated with the volcanism [5]. We develop the model here, suggested by [5], that the high-silica materials are another manifestation of acid-sulfate processes associated with fumarolic and hydrothermal activity at Home Plate. This is done by analogy with basaltic materials altered by acid sulfate processes on the Island of Hawaii.

  9. Prone to excitement: adolescent females with Non-suicidal self-injury (NSSI) show altered cortical pattern to emotional and NSS-related material.

    Science.gov (United States)

    Plener, Paul L; Bubalo, Nikola; Fladung, Anne K; Ludolph, Andrea G; Lulé, Dorothée

    2012-01-01

    Emotion-regulation difficulties have been identified as one of the core components in Non-suicidal self-injury (NSSI), a behaviour often beginning in adolescence. This pilot study evaluated differences in emotion processing between 18 female adolescents with and without NSSI by using verbal responses and functional magnetic resonance imaging (fMRI). Responses to pictures taken from the International Affective Picture System and slides with reference to NSSI were recorded both by verbal rating of valence and arousal and by fMRI. The NSSI group rated pictures with self-injurious reference as significantly more arousing than controls. For emotional pictures, the NSSI group showed a significantly stronger brain response in the amygdala, hippocampus and anterior cingulate cortex bilaterally. Depression explained differences between groups in the limbic area. Furthermore, the NSSI group also showed increased activity in the middle orbitofrontal cortex, and inferior and middle frontal cortex when viewing NSSI picture material. Participants with NSSI showed decreased activity in correlation to arousal in the occipital cortex and to valence in inferior frontal cortex when watching emotional pictures. The fMRI data support the notion that individuals with NSSI show an altered neural pattern for emotional and NSSI pictures. Behavioural data highlight proneness to excitement regarding NSSI topics. This fMRI study provides evidence for emotion-regulation deficits in the developing brain of adolescents with NSSI.

  10. Polysulphone composite membranes modified with two types of carbon additives as a potential material for bone tissue regeneration

    Indian Academy of Sciences (India)

    ALICJA WEDEL-GRZENDA; ANETA FRACZEK-SZCZYPTA; MAURICIO TERRONES; ANA LAURA ELÍAS; MALGORZATA LEKKA; ELZBIETA MENASZEK; STANISLAW BLAZEWICZ

    2017-02-01

    This study presents a detailed evaluation of the impact of carbon fibrous materials on the physicochemical properties of polysulphone (PSU) membranes and their preliminary osteoblast-like cells response in vitro. Multiwalled carbon nanotubes (MWCNTs) and short carbon fibres (SCFs) were incorporated into PSU and membranes were produced by the phase inversion method. Then, the physicochemical properties of the membranes’ surface were investigated. Scanning electron microscopy (SEM) was used to evaluate microstructure and porosity. Surface properties such as roughness, wettability and surface energy were evaluated using atomic force microscopy (AFM), contact profilometry and a goniometer, respectively. The presence of carbon fibrous additives in the PSU matrix improved its hydrophilicity. Porosity and topography of the PSU membranes were also changed upon incorporation of carbon additives. The mechanical properties of the PSU membranes were improved after SCF addition. All physicochemical properties of the obtained composite membranes had significant impact on the osteoblast-like cells response. Preliminary viability tests indicated biocompatibility of all membranes.

  11. Theory-Guided Materials Design of Multi-Phase Ti-Nb Alloys with Bone-Matching Elastic Properties

    Directory of Open Access Journals (Sweden)

    Jörg Neugebauer

    2012-10-01

    Full Text Available We present a scale-bridging approach for modeling the integral elasticresponse of polycrystalline composite that is based on a multi-disciplinary combination of(i parameter-free first-principles calculations of thermodynamic phase stability andsingle-crystal elastic stiffness; and (ii homogenization schemes developed forpolycrystalline aggregates and composites. The modeling is used as a theory-guidedbottom-up materials design strategy and applied to Ti-Nb alloys as promising candidatesfor biomedical implant applications. The theoretical results (i show an excellent agreementwith experimental data and (ii reveal a decisive influence of the multi-phase character ofthe polycrystalline composites on their integral elastic properties. The study shows thatthe results based on the density functional theory calculations at the atomistic level canbe directly used for predictions at the macroscopic scale, effectively scale-jumping severalorders of magnitude without using any empirical parameters.

  12. Impact of bone graft harvesting techniques on bone formation and graft resorption

    DEFF Research Database (Denmark)

    Saulacic, Nikola; Bosshardt, Dieter D; Jensen, Simon S;

    2015-01-01

    formation and graft resorption in vivo. MATERIAL AND METHODS: Four harvesting techniques were used: (i) corticocancellous blocks particulated by a bone mill; (ii) bone scraper; (iii) piezosurgery; and (iv) bone slurry collected from a filter device upon drilling. The grafts were placed into bone defects...

  13. In Vivo Assessment of Bone Regeneration in Alginate/Bone ECM Hydrogels with Incorporated Skeletal Stem Cells and Single Growth Factors

    Science.gov (United States)

    Gothard, David; Smith, Emma L.; Kanczler, Janos M.; Black, Cameron R.; Wells, Julia A.; Roberts, Carol A.; White, Lisa J.; Qutachi, Omar; Peto, Heather; Rashidi, Hassan; Rojo, Luis; Stevens, Molly M.; El Haj, Alicia J.; Rose, Felicity R. A. J.; Shakesheff, Kevin M.; Oreffo, Richard O. C.

    2015-01-01

    The current study has investigated the use of decellularised, demineralised bone extracellular matrix (ECM) hydrogel constructs for in vivo tissue mineralisation and bone formation. Stro-1-enriched human bone marrow stromal cells were incorporated together with select growth factors including VEGF, TGF-β3, BMP-2, PTHrP and VitD3, to augment bone formation, and mixed with alginate for structural support. Growth factors were delivered through fast (non-osteogenic factors) and slow (osteogenic factors) release PLGA microparticles. Constructs of 5 mm length were implanted in vivo for 28 days within mice. Dense tissue assessed by micro-CT correlated with histologically assessed mineralised bone formation in all constructs. Exogenous growth factor addition did not enhance bone formation further compared to alginate/bone ECM (ALG/ECM) hydrogels alone. UV irradiation reduced bone formation through degradation of intrinsic growth factors within the bone ECM component and possibly also ECM cross-linking. BMP-2 and VitD3 rescued osteogenic induction. ALG/ECM hydrogels appeared highly osteoinductive and delivery of angiogenic or chondrogenic growth factors led to altered bone formation. All constructs demonstrated extensive host tissue invasion and vascularisation aiding integration and implant longevity. The proposed hydrogel system functioned without the need for growth factor incorporation or an exogenous inducible cell source. Optimal growth factor concentrations and spatiotemporal release profiles require further assessment, as the bone ECM component may suffer batch variability between donor materials. In summary, ALG/ECM hydrogels provide a versatile biomaterial scaffold for utilisation within regenerative medicine which may be tailored, ultimately, to form the tissue of choice through incorporation of select growth factors. PMID:26675008

  14. N-phenacylthiazolium bromide reduces bone fragility induced by nonenzymatic glycation.

    Directory of Open Access Journals (Sweden)

    Brian S Bradke

    Full Text Available Nonenzymatic glycation (NEG describes a series of post-translational modifications in the collagenous matrices of human tissues. These modifications, known as advanced glycation end-products (AGEs, result in an altered collagen crosslink profile which impacts the mechanical behavior of their constituent tissues. Bone, which has an organic phase consisting primarily of type I collagen, is significantly affected by NEG. Through constant remodeling by chemical resorption, deposition and mineralization, healthy bone naturally eliminates these impurities. Because bone remodeling slows with age, AGEs accumulate at a greater rate. An inverse correlation between AGE content and material-level properties, particularly in the post-yield region of deformation, has been observed and verified. Interested in reversing the negative effects of NEG, here we evaluate the ability of n-phenacylthiazolium bromide (PTB to cleave AGE crosslinks in human cancellous bone. Cancellous bone cylinders were obtained from nine male donors, ages nineteen to eighty, and subjected to one of six PTB treatments. Following treatment, each specimen was mechanically tested under physiological conditions to failure and AGEs were quantified by fluorescence. Treatment with PTB showed a significant decrease in AGE content versus control NEG groups as well as a significant rebound in the post-yield material level properties (p<0.05. The data suggest that treatment with PTB could be an effective means to reduce AGE content and decrease bone fragility caused by NEG in human bone.

  15. Evaluation of laboratory and industrial meat and bone meal combustion residue as cadmium immobilizing material for remediation of polluted aqueous solutions: "chemical and ecotoxicological studies".

    Science.gov (United States)

    Coutand, M; Deydier, E; Cyr, M; Mouchet, F; Gauthier, L; Guilet, R; Savaete, L Bernues; Cren, S; Clastres, P

    2009-07-30

    Meat and Bone Meals (MBM) combustion residues (ashes) are calcium and phosphate-rich materials. The aim of this work is to evaluate ashes efficiency for remediation of cadmium-contaminated aqueous solutions, and to assess the bioavailability of cadmium on Xenopus laevis larvae. In this study both industrial (MBM-BA) and laboratory (MBM-LA) ashes are compared regarding their efficiency. Kinetic investigations reveal that cadmium ions are quickly immobilized, with a maximum cadmium uptake at 57 mg Cd(2+)/g of ashes for MBM-LA, two times higher than metal uptake quantity of MBM-BA, in our experimental conditions. Chemical and X-ray diffraction analysis (XRD) reveal that Cd(2+) is mainly immobilized as Ca(10-x)Cd(x)(PO(4))(6)(OH)(2) by both ashes, whereas otavite, Cd(CO(3)), is also involved for MBM-LA in cadmium uptake. Otavite formation could be explained by the presence of carbonates in MBM-LA, as observed by IR. Genotoxicity of cadmium solution on Xenopus larvae is observed at 0.02, 0.2 and 2mg Cd(2+)/L. However addition of only 0.1g/L MBM-LA inhibits these effects for the above concentration values whereas Cd(2+) bioaccumulation in larvae's liver is similar for both experiments, with and without ashes.

  16. Microtomographic and morphometric characterization of a bioceramic bone substitute in dental implantology

    Directory of Open Access Journals (Sweden)

    Deborah Meleo

    2012-01-01

    Full Text Available In recent years, bone tissue regeneration studies have led to a deeper knowledge of chemical and structural features of the best biomaterials to be used as replacements for lost bone structures, with the autologus bone still today the only graft material able to ostegenerate, osteinduct and/or osteoconduct. The difficulties of the small available amount of autologus bone, together with morbidity of a second surgical operation on the same patient, have been overcome using both synthetic and biologic substitute bones. The possibility of investigating morphometric characteristics of substitute bones makes it possible to evaluate the predictability of regenerative processes and, so far, a range of different methods have been used for the purpose. X-ray microtomography (micro-CT is a miniaturized form of conventional tomography, able to analyze the internal structure of small objects, performing three-dimensional images with high spatial resolution (<10 micron pixel size. For a correct analysis, samples need not be altered or treated in any way, as micro-CT is a non-invasive and non-destructive technique. It shows promising results in biomaterial studies and tissue engineering. This work shows the potential applications of this microtomographic technique by means of an in vitro analysis system, in characterizing morphometric features of human bone tissue, and contributes to the use of this technique in studies concerning biomaterials and bioscaffolds inserted in bone tissue.

  17. Bone healing around nanocrystalline hydroxyapatite, deproteinized bovine bone mineral, biphasic calcium phosphate, and autogenous bone in mandibular bone defects

    DEFF Research Database (Denmark)

    Broggini, Nina; Bosshardt, Dieter D; Jensen, Simon S;

    2015-01-01

    The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled with nanocr......The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled...... with nanocrystalline hydroxyapatite (HA-SiO), deproteinized bovine bone mineral (DBBM), biphasic calcium phosphate (BCP) with a 60/40% HA/β-TCP (BCP 60/40) ratio, or particulate autogenous bone (A) for histological and histomorphometric analysis. At 2 weeks, percent filler amongst the test groups (DBBM (35.65%), HA...

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Cancer Cell Colonisation in the Bone Microenvironment

    Directory of Open Access Journals (Sweden)

    Casina Kan

    2016-10-01

    Full Text Available Bone metastases are a common complication of epithelial cancers, of which breast, prostate and lung carcinomas are the most common. The establishment of cancer cells to distant sites such as the bone microenvironment requires multiple steps. Tumour cells can acquire properties to allow epithelial-to-mesenchymal transition, extravasation and migration. Within the bone metastatic niche, disseminated tumour cells may enter a dormancy stage or proliferate to adapt and survive, interacting with bone cells such as hematopoietic stem cells, osteoblasts and osteoclasts. Cross-talk with the bone may alter tumour cell properties and, conversely, tumour cells may also acquire characteristics of the surrounding microenvironment, in a process known as osteomimicry. Alternatively, these cells may also express osteomimetic genes that allow cell survival or favour seeding to the bone marrow. The seeding of tumour cells in the bone disrupts bone-forming and bone-resorbing activities, which can lead to macrometastasis in bone. At present, bone macrometastases are incurable with only palliative treatment available. A better understanding of how these processes influence the early onset of bone metastasis may give insight into potential therapies. This review will focus on the early steps of bone colonisation, once disseminated tumour cells enter the bone marrow.

  20. Cancer Cell Colonisation in the Bone Microenvironment

    Science.gov (United States)

    Kan, Casina; Vargas, Geoffrey; Le Pape, François; Clézardin, Philippe

    2016-01-01

    Bone metastases are a common complication of epithelial cancers, of which breast, prostate and lung carcinomas are the most common. The establishment of cancer cells to distant sites such as the bone microenvironment requires multiple steps. Tumour cells can acquire properties to allow epithelial-to-mesenchymal transition, extravasation and migration. Within the bone metastatic niche, disseminated tumour cells may enter a dormancy stage or proliferate to adapt and survive, interacting with bone cells such as hematopoietic stem cells, osteoblasts and osteoclasts. Cross-talk with the bone may alter tumour cell properties and, conversely, tumour cells may also acquire characteristics of the surrounding microenvironment, in a process known as osteomimicry. Alternatively, these cells may also express osteomimetic genes that allow cell survival or favour seeding to the bone marrow. The seeding of tumour cells in the bone disrupts bone-forming and bone-resorbing activities, which can lead to macrometastasis in bone. At present, bone macrometastases are incurable with only palliative treatment available. A better understanding of how these processes influence the early onset of bone metastasis may give insight into potential therapies. This review will focus on the early steps of bone colonisation, once disseminated tumour cells enter the bone marrow. PMID:27782035

  1. Gaucher disease and bone manifestations.

    Science.gov (United States)

    Marcucci, Gemma; Zimran, Ari; Bembi, Bruno; Kanis, John; Reginster, Jean-Yves; Rizzoli, Renè; Cooper, Cyrus; Brandi, Maria Luisa

    2014-12-01

    Gaucher disease is a relatively rare metabolic disease caused by the inherited deficiency of the lysosomal enzyme glucocerebrosidase. Gaucher disease affects multiple organs, among which is the skeleton. Bone involvement occurs frequently in Gaucher disease, and is one of its most debilitating features, reducing the quality of life of patients. Bone status is an important consideration for treatment to ameliorate symptoms and reduce the risk of irreversible complications. We have conducted a systematic review of all the various aspects of Gaucher disease, focusing on different skeletal manifestations, pathophysiology of bone alterations, clinical symptoms, and current diagnostic and therapeutic approaches.

  2. Novel approaches to bone grafting: porosity, bone morphogenetic proteins, stem cells, and the periosteum.

    Science.gov (United States)

    Petrochenko, Peter; Narayan, Roger J

    2010-01-01

    The disadvantages involving the use of a patient's own bone as graft material have led surgeons to search for alternative materials. In this review, several characteristics of a successful bone graft material are discussed. In addition, novel synthetic materials and natural bone graft materials are being considered. Various factors can determine the success of a bone graft substitute. For example, design considerations such as porosity, pore shape, and interconnection play significant roles in determining graft performance. The effective delivery of bone morphogenetic proteins and the ability to restore vascularization also play significant roles in determining the success of a bone graft material. Among current approaches, shorter bone morphogenetic protein sequences, more efficient delivery methods, and periosteal graft supplements have shown significant promise for use in autograft substitutes or autograft extenders.

  3. Changes of hyoid bone position following treatment of class II div1 malocclusion with Farmand functional appliance

    Directory of Open Access Journals (Sweden)

    Yassaei S

    2007-01-01

    Full Text Available Background and Aim: Unlike other bones of the head and neck, hyoid bone has no bony articulations. It is connected to mandible, cranium and pharynx through muscles and ligaments. During treatment with functional appliance in patients with class II div1 malocclusion, mandible is positioned in inferior and anterior direction. Regarding the relation between hyoid and mandibular bone, alterations of hyoid bone position can be a result of functional appliance therapy. The aim of this study was to evaluate the changes of hyoid bone position following treatment with Farmand functional appliance in patients with class II div 1 malocclusion. Materials and Methods: In this before-after clinical trial, 28 patients with class II div 1 malocclusion which were under treatment with Farmand functional appliance for 11 months were selected. Facial growth in vertical, normal or horizontal direction was determined by cephalometric measurement. Data were analyzed with Paired-t test to compare the differences of mean values pre and post treatment. Variance analysis was used to compare the three growth patterns. P<0.05 was considered as the limit of significance. Results: Hyoid bone shifted significantly forward in horizontal dimension (P<0.01 and non-significantly upward in vertical dimension. There was no significant difference among the three studied groups with respect to hyoid bone position alterations in horizontal dimension but significant difference was observed between horizontal and vertical growth pattern in vertical dimension (P<0.05. There was significant correlation between decrease of ANB angle and forward movement of hyoid bone. Conclusion: Based on the results of this study, treatment with Farmand functional appliance (Fa II leads to significant alterations in the position and anterior displacement of the hyoid bone.

  4. Evaluation of meat and bone meal combustion residue as lead immobilizing material for in situ remediation of polluted aqueous solutions and soils: "chemical and ecotoxicological studies".

    Science.gov (United States)

    Deydier, E; Guilet, R; Cren, S; Pereas, V; Mouchet, F; Gauthier, L

    2007-07-19

    As a result of bovine spongiform encephalopathy (BSE) crisis, meat and bone meal (MBM) production can no longer be used to feed cattle and must be safely disposed of or transformed. MBM specific incineration remains an alternative that could offer the opportunity to achieve both thermal valorization and solid waste recovery as ashes are calcium phosphate-rich material. The aim of this work is to evaluate ashes efficiency for in situ remediation of lead-contaminated aqueous solutions and soils, and to assess the bioavailability of lead using two biological models, amphibian Xenopus laevis larvae and Nicotiana tabaccum tobacco plant. With the amphibian model, no toxic or genotoxic effects of ashes are observed with concentrations from 0.1 to 5 g of ashes/L. If toxic and genotoxic effects of lead appear at concentration higher than 1 mg Pb/L (1 ppm), addition of only 100 mg of ashes/L neutralizes lead toxicity even with lead concentration up to 10 ppm. Chemical investigations (kinetics and X-ray diffraction (XRD) analysis) reveals that lead is quickly immobilized as pyromorphite [Pb10(PO4)6(OH)2] and lead carbonate dihydrate [PbCO(3).2H2O]. Tobacco experiments are realized on contaminated soils with 50, 100, 2000 and 10000 ppm of lead with and without ashes amendment (35.3g ashes/kg of soil). Tobacco measurements show that plant elongation is bigger in an ashes-amended soil contaminated with 10000 ppm of lead than on the reference soil alone. Tobacco model points out that ashes present two beneficial actions as they do not only neutralize lead toxicity but also act as a fertilizer.

  5. Stress-induced alterations in the programmed natural cycles of post-natal lymphoid organ development in C57BL/6 mice: Evidence for a regulatory feedback relationship between bone marrow and thymus.

    Science.gov (United States)

    Domínguez-Gerpe, Lourdes

    2007-01-01

    This study investigated some effects of weaning and immobilization stress in C57BL/6 mice aged 22-68 days, i.e., over a period including activation of the hypothalamus-pituitary-adrenal (HPA) axis and puberty. Specifically, the study evaluated the evolution, over the referred age interval, of a set of variables (body, thymus, spleen and axillary lymph nodes weights, the proportion of lymphoid cells in the bone marrow, the relative chemoattraction capacity of thymic supernatants for lymphoid cells and the migratory capacity of bone marrow lymphoid cells) in either weaned mice or weaned mice subjected to immobilization stress, compared to "non-stressed" unweaned mice. Cyclic patterns, observed for most variables in unweaned mice, were especially pronounced in two cases: the relative migratory capacity of bone marrow lymphoid cells collected at different ages towards neonatal thymic supernatant, and the relative chemoattraction capacity of thymic supernatants of different ages as tested against a sample of bone marrow lymphoid cells from mice aged 35 days. Weaning stress tended to intensify the involution stages of the cycles in thymus, spleen and lymph node weight, but increased the relative proportion of lymphoid cells in the bone marrow cell population. Both types of exogenous stress tended to affect cycle phase, i.e., cycle peaks and troughs were shifted in time. Correlations were observed between patterns seen in the thymus and bone marrow, suggesting the existence of an autoregulatory feedback loop governing pre-T cell migration and bone marrow/thymus homeostasis. These results also suggest that exogenous stress acts as a non-programmed regulator, modulating the naturally programmed cyclic patterns.

  6. The Experimental Research in Repairing the Bone Defect Around Dental Implant by a New Type Material%Gel-HA-M/PRP复合材料对种植体周围骨缺损修复的实验研究

    Institute of Scientific and Technical Information of China (English)

    尚新华; 周健; 李全利; 孙传锋; 窦晓晨

    2011-01-01

    目的:观察明胶-羟基磷灰石-米诺环素(Gel-HA-M)纳米复合物与富血小板血浆(platelet-rich plasma,PRP)复合(GEL-HA-M/PRP)修复种植体周围骨缺损的效果,探讨其作为种植体周围骨缺损修复材料的可行性.方法:普通健康杂种犬6只,拔除双侧下颌第二、三、四前磨牙,3个月后每侧拔牙处植入3枚直径4 mm、长11 mm的种植体,并于钛钉周围制造宽约1.5mm、深4mm的环形骨缺损,分别植入自体骨、Gel-HA-M/PRP,最后为空白作为对照.种植术后4、8、12周各处死2只动物,进行大体、影像学及组织学观察.结果:实验组种植体周围骨缺损区较空白对照组新骨形成量多、外形好,并未见材料剩余;自体骨组可见成熟骨组织,较多新骨形成,同时有少量骨吸收存在;空白组主要为纤维性结合,有少量的骨组织再生.结论:提示Gel-HA-M纳米复合物的PRP复合凝胶能够促进种植体周围骨缺损的修复.%Objective: To investigate the feasibility of a hybrid biomaterial gelatin-apatite-minocycline nanocomposite combined with platelet-rich plasma (Gel-HA-M/PRP) to repair the bone defects around dental implants.Methods: 6 healthy mongrel dogs, their 2nd, 3rd, and 4th premolars were extracted from both sides of the mandible.Three months after extraction, 3 implants with the diameter of 4 mm and length of 11 mm were separately implanted in each side of the mandible.At the same time, a bone defect with the size of 1.5 mm in width and 4 mm in depth was created around the neck of each implant.The bone defects were grafted with autogenous bone, Gel-HA-M/PRP, and kept void as control respectively.Every 2 dogs were sacrificed at 4-, 8-, and 12-week respectively after the implantation.Specimen were examined by X-ray and histopathology sections.Results: In hybrid material grafted wounds, more new bone formation were observed, the Gel-HA-M nanocomposite was fully adsorbed.In autogenous bone grafted wounds, mature bone and a few

  7. Periodontal materials.

    Science.gov (United States)

    Darby, I

    2011-06-01

    Periodontics is more associated with debridement of periodontal pockets and not generally thought of as using dental materials in the treatment of patients. However, the last 30 years have seen the development of materials used in regeneration of the periodontal tissues following periodontal disease, guided tissue regeneration, and the use of these materials in bone regeneration more recently, guided bone regeneration. The materials used include bone grafts and membranes, but also growth factors and cells-based therapies. This review provides an overview of the materials currently used and looks at contemporary research with a view to what may be used in the future. It also looks at the clinical effectiveness of these regenerative therapies with an emphasis on what is available in Australia.

  8. Properties of deproteinized bone for reparation of big segmental defect in long bone

    Institute of Scientific and Technical Information of China (English)

    JIAN Yue-kui; TIAN Xiao-bin; LI Bo; QIU Bing; ZHOU Zuo-jia; YANG Zheng; LI Qi-hong

    2008-01-01

    Objective: To explore suitable scaffold material for big segmental long bone defect by studying the properties of the prepared deproteinized bone. Methods: Cancellated bone were made as 30 mm ×3 mm ×3 mm bone blocks from inferior extremity of pig femur along bone trabecula. The deproteinized bone was prepared with an improved method. Their morphological features, components, cell compatibility, mechanical and immunological properties were investigated respectively. Results: Deproteinized bone maintained natural re ticular pore system. The main organic material is collagen Ⅰand inorganic composition is hydroxyapatite. It has good mechanical properties, cell adhesion rate and histocompatibility. Conlusion: This deproteinized bone can be applicable as scaffold for reparation of big segmental defect in long bone.

  9. Raman spectroscopy of bone metastasis

    Science.gov (United States)

    Esmonde-White, Karen A.; Sottnik, Joseph; Morris, Michael; Keller, Evan

    2012-02-01

    Raman spectroscopy of bone has been used to characterize chemical changes occurring in diseases such as osteoporosis, osteoarthritis and osteomyelitis. Metastasis of cancer into bone causes changes to bone quality that are similar to those observed in osteoporosis, such as decreased bone strength, but with an accelerated timeframe. In particular, osteolytic (bone degrading) lesions in bone metastasis have a marked effect on patient quality of life because of increased risk of fractures, pain, and hypercalcemia. We use Raman spectroscopy to examine bone from two different mouse models of osteolytic bone metastasis. Raman spectroscopy measures physicochemical information which cannot be obtained through standard biochemical and histological measurements. This study was reviewed and approved by the University of Michigan University Committee on the Care and Use of Animals. Two mouse models of prostate cancer bone metastasis, RM1 (n=3) and PC3-luc (n=4) were examined. Tibiae were injected with RM1 or PC3-luc cancer cells, while the contralateral tibiae received a placebo injection for use as controls. After 2 weeks of incubation, the mice were sacrificed and the tibiae were examined by Raman microspectroscopy (λ=785 nm). Spectroscopic markers corresponding to mineral stoichiometry, bone mineralization, and mineral crystallinity were compared in spectra from the cancerous and control tibiae. X-ray imaging of the tibia confirmed extensive osteolysis in the RM1 mice, with tumor invasion into adjoining soft tissue and moderate osteolysis in the PC3-luc mice. Raman spectroscopic markers indicate that osteolytic lesions are less mineralized than normal bone tissue, with an altered mineral stoichiometry and crystallinity.

  10. Evaluation of a synthetic bone defect test model to aid in the selection of materials for use in vertebral body compression fracture repair.

    Science.gov (United States)

    Carroll, Michael; Lewis, Gladius; Xu, J; Moseley, Jon; Cole, Jantzen; Haggard, Warren

    2004-01-01

    A synthetic test model was developed to assist in screening injectable cements with a focus on mechanical strength for vertebral body compression fracture repair. The two-part defect model consisted of a polyurethane foam cube to simulate trabecular bone and a defect to which various injectable cements could be introduced. In addition, a finite element analysis model was developed and the results were compared to laboratory testing. Agreement was found between the finite element analysis and test results. Once the finite element analysis model was validated with experimental data, an additional finite element analysis was conducted to study various parameters affecting mechanical performance such as simulated bone and cement stiffness. Finite element analysis models were also created using orthotropic bone properties typical of healthy trabecular bone and were compared to various foam stiffnesses. The foam model was a good in vitro representation of actual trabecular bone found in vertebral bodies and is a valid model to evaluate the mechanical strength of injectable cements for percutaneous vertebral body fracture repair.

  11. Different bone graft fusion materials applied in lumbar interbody fusion%不同植骨融合材料在腰椎椎体间脊柱融合中的应用

    Institute of Scientific and Technical Information of China (English)

    覃建朴; 王翀; 张朋云; 曹广如; 蔡玉强; 廖文波

    2016-01-01

    背景:脊柱融合治疗时选择合适的替代移植骨具有重要的意义,能够解决自体骨移植及其他移植材料带来的弊端。目的:观察不同植骨融合材料性能,探讨不同植骨融合材料在犬腰椎椎体间脊柱融合中的应用效果。方法:选取45只中华田园犬建立腰椎椎体间脊柱融合模型,建模后随机分3组,分别植入自体髂骨、重组人骨形态发生蛋白2复合材料和同种异体髂骨,分析不同植骨融合材料在犬腰椎椎体间脊柱融合中的效果。结果与结论:①融合率:重组人骨形态发生蛋白2复合材料组犬融合率显著高于其他组(P <0.05);②Oswestry 功能障碍指数:重组人骨形态发生蛋白2复合材料组术后 Oswestry 功能障碍指数显著低于其他2组(P <0.05);②组织学形态:苏木精-伊红染色显示,术后12周,与其他2组相比,重组人骨形态发生蛋白2犬完全骨性融合,且形成了连续骨小梁,植入骨与犬上下椎体完全粘连;④结果提示:重组人骨形态发生蛋白2复合材料更能够促更好地促进脊柱愈合,效果优于自体和同种异体骨移植。%BACKGROUND: The choice of suitable bone graft substitute is vital for spinal fusion treatment, which can solve some limitations caused by autogenous bone graft and other materials. OBJECTIVE: To investigate properties of different bone graft fusion materials, and to explore their application in dog spinal fusion of lumbar vertebral body. METHODS: Forty-five Chinese rural dogs were enrol ed to prepare lumbar interbody fusion models, and then were randomized into three groups transplanted with autogenous ilium, recombinant human bone morphogenetic protein-2 composite or al ograft ilium, respectively. Afterwards, effects of different materials in the lumbar interbody fusion were analyzed. RESULTS AND CONCLUSION: The fusion rate of the composite group was significantly higher than those of the other

  12. Bone x-ray

    Science.gov (United States)

    ... or broken bone Bone tumors Degenerative bone conditions Osteomyelitis (inflammation of the bone caused by an infection) ... Multiple myeloma Osgood-Schlatter disease Osteogenesis imperfecta Osteomalacia Osteomyelitis Paget disease of the bone Rickets X-ray ...

  13. Cytocompatibility between novel nerve conduit composite materials and bone marrow mesenchymal stem cells%新型神经导管复合材料与骨髓间充质干细胞的相容性*★

    Institute of Scientific and Technical Information of China (English)

    胡辉; 张伟才; 黄继锋; 严琼娇; 殷义霞; 李世普

    2013-01-01

      结果与结论:MTT检测结果显示,共培养5,7 d,实验组吸光度值高于对照组(P OBJECTIVE:To evaluate the cytocompatibility of rat bone marrow mesenchymal stem cel s with (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composites. METHODS:Passage 3 bone marrow mesenchymal stem cel s which were isolated from Sprague-Dawley rats were co-cultured with (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composite materials or their extracts, serving as experimental control. Another bone marrow mesenchymal stem cel s cultured in the culture medium containing 10%fetal bovine serum served as controls. Cel growth, survival and apoptosis on the composite materials were observed. RESULTS AND CONCLUSION:Results from 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that absorbance values in the experimental group were higher than those in the control group after co-culture for days 5 and 7 (P<0.05). Annexin V-FITC/PI double staining results showed that the apoptosis rate of the experimental group was significantly lower than that of the control group (P<0.05). Under a scanning electron microscope, bone marrow mesenchymal stem cel s grew wel on the surface of (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composite materials. Many protrusions ran out from the cel s, and they were woven into a mesh, which was typical performance of neuron-like cel s. These findings indicate that (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composite materials have good cytocompatibility with bone marrow mesenchymal stem cel s, which can be regarded as an excel ent carrier for artificial nerve construction.

  14. Mechanisms of multiple myeloma bone disease

    Science.gov (United States)

    Galson, Deborah L; Silbermann, Rebecca; Roodman, G David

    2012-01-01

    Multiple myeloma is the second most common hematological malignancy and the most frequent cancer to involve the skeleton. Multiple myeloma bone disease (MMBD) is characterized by abnormal bone remodeling with dysfunction of both bone resorption and bone formation, and thus can be used as a paradigm for other inflammatory bone diseases, and the regulation of osteoclasts and osteoblasts in malignancy. Studies of MMBD have identified novel regulators that increase osteoclastogenesis and osteoclast function, repress osteoblast differentiation, increase angiogenesis, or permanently alter stromal cells. This review will discuss the current understanding of mechanisms of osteoclast and osteoblast regulation in MMBD, and therapeutic approaches currently in use and under development that target mediators of bone destruction and blockade of bone formation for myeloma patients, including new anabolic therapies. PMID:23951515

  15. 负离子材料对骨质瓷性能影响研究%Study on Effect of Negative Ion Materials on the Properties of Bone-China

    Institute of Scientific and Technical Information of China (English)

    王秀文; 李悦; 杨欢欢

    2016-01-01

    为使骨质瓷具有释放负离子的功能,在传统骨质瓷釉料配方的基础上,添加具有释放负离子功能的负离子材料.将负离子粉和稀土类原料分别加入骨质瓷釉料中,研究负离子材料对骨质瓷性能影响规律,确定合适的负离子材料的种类及添加量.结果表明:在骨质瓷基础釉料配方中,引入负离子粉较稀土类氧化物,样品对蒸馏水pH值影响最大,负离子释放效果最为明显.随着负离子粉添加量的增多,骨质瓷样品负离子释放量增多,综合考虑负离子释放效果、产品性能及产品成本,负离子粉添加量控制在3~4%为合适.负离子粉影响骨质瓷白度,引入越多白度降低越明显,通过钴蓝调色,能使白度达到81.09%,使其达到国家规定的骨质瓷白度要求.加入负离子粉后,样品的热稳定性满足国标规定的骨质瓷性能要求,但对釉层的显微结构产生了一定的影响,需要适当微调基础釉料配方,合理控制烧成制度,保证釉面质量.%In order to make bone-china can possess the function of anon releasing,the negative ion materials with ability of anion releasing were adopted based on the formula of traditional bone-china glaze.Negative ion powders and rare earth materials were added in the bone-china glaze.The effect of negative ion materials on the properties of bone china were discussed,and the negative ion materials and the addition content were confirmed.Studying showed that the influence of negative ion material inducer on PH of distilled water when added several negative ion materials to bone china glaze was largest,meanwhile the most negative ions were released by the burnt product which introduces negative ion powder.The electronegative ion releasing concentration of bone-china increased when the addition of negative ion powders increased.Considering the effect of electronegative ion realeasing,product properties and product cost,the addition of negative ion powder

  16. 四环素骨诱导活性材料整复牙槽缺损的实验研究%Experimental study on repairing the defect in alveolar bone with tetracycline activated materials for bone guide

    Institute of Scientific and Technical Information of China (English)

    刘牧菲

    2000-01-01

    目的:将盐酸四环素处理的人离体非功能牙块用于诱导骨再生技术中,观察和比较其对牙槽骨再生修复的影响。方法:拔除大鼠第一磨牙近中根做人工牙槽缺损。置入盐酸四环素处理的离体人牙块,以盐酸处理的离体人牙块为阳性对照,未做任何处理的离体人牙块为阴性对照。不同时期取材做组织观察和评价。结果:四环素处理组炎症反应小,早期成骨明显。中晚期成骨量明显高于对照组。结论:盐酸四环素处理的人离体非功能牙块有抑制骨吸收,诱导、促进牙槽骨再生等作用。%Objective:The effect on alveolar bone regeneration and repair was observed and compared with guide bone regeneration technique -isolated human dentin blocks treated with tetracycline-HCL.Methods:The first molar mesial roots of rats were extracted as defects in alveolar bone and the isolated human dentin blocks treated with tetracycline-HCL as positive control and and untreated with anything as negative control were implanted the defect sites for histologic observation and evaluation at the different periods.Results:There is less inflammatory (in tetracycline treatment groups than control at early stages and they showed marked osteaogenesis),but the osteogenic quantity is larger than control groups at middle and late stages. Conclusion:The isolated teeth blocks treated with tetracycline HCL have actions on inhibiting bone resorption, and promoting alveolar bone generation.

  17. Chemical and Mineralogical Characterization of Acid-Sulfate Alteration of Basaltic Material on Mauna Kea Volcano, Hawaii: Jarosite and Hydrated Halloysite

    Science.gov (United States)

    Graff, Trevor G.; Morris, R. V.; Archilles C. N.; Agresti, D. G.; Ming, D. W.; Hamilton, J. C.; Mertzman, S. A.; Smith, J.

    2012-01-01

    Sulfates have been identified on the martian surface during robotic surface exploration and by orbital remote sensing. Measurements at Meridiani Planum (MP) by the Alpha-Particle X-ray Spectrometer (APXS) and Mossbauer (MB) instruments on the Mars Exploration Rover Opportunity document the presence of a ubiquitous sulfate-rich outcrop (20-40% SO3) that has jarosite as an anhydrous Fe3+-sulfate [1- 3]. The presence of jarosite implies a highly acidic (pH volcano, Hawaii) resulted in jarosite and alunite as sulfate-bearing alteration products [11-14]. Other, more soluble, sulfates may have formed, but were leached away by rain and melting snow. Acidsulfate processes on Puu Poliahu also formed hematite spherules similar (except in size) to the hematite spherules observed at MP as an alteration product [14]. Phyllosilicates, usually smectite }minor kaolinite are also present as alteration products [13]. We discuss here an occurrence of acid-sulfate alteration on Mauna Kea Volcano (Hawaii). We report VNIR spectra (0.35-2.5 microns ASD spectrometer), Mossbauer spectra (MER-like ESPI backscatter spectrometer), powder XRD (PANalytical), and major element chemical compositions (XRF with LOI and Fe redox) for comparison to similar data acquired or to be acquired by MRO-CRISM and MEx OMEGA, MERMB, MSL-CheMin, and MER and MSL APXS, respectively.

  18. Automated radiogrammetry is a feasible method for measuring bone quality and bone maturation in severely disabled children

    Energy Technology Data Exchange (ETDEWEB)

    Mergler, Sandra [Erasmus MC, Department of General Practice and Intellectual Disability Medicine, University Medical Centre, Rotterdam (Netherlands); Care and Service Centre for People with Intellectual Disabilities, Medical Department ASVZ, Sliedrecht (Netherlands); Man, Stella A. de [Amphia Hospital, Department of Paediatrics, Breda (Netherlands); Boot, Annemieke M. [University of Groningen, Department of Paediatric Endocrinology, University Medical Centre Groningen, Groningen (Netherlands); Heus, Karen G.C.B.B. [Erasmus MC, Department of General Paediatrics, Sophia Children' s Hospital, University Medical Centre, Rotterdam (Netherlands); Huijbers, Wim A.R. [Beatrix Hospital, Department of Paediatrics, Gorinchem (Netherlands); Rijn, Rick R. van [Emma Children' s Hospital/Academic Medical Centre, Department of Radiology, Amsterdam (Netherlands); Penning, Corine; Evenhuis, Heleen M. [Erasmus MC, Department of General Practice and Intellectual Disability Medicine, University Medical Centre, Rotterdam (Netherlands)

    2016-06-15

    Children with severe neurological impairment and intellectual disability are prone to low bone quality and fractures. We studied the feasibility of automated radiogrammetry in assessing bone quality in this specific group of children. We measured outcome of bone quality and, because these children tend to have altered skeletal maturation, we also studied bone age. We used hand radiographs obtained in 95 children (mean age 11.4 years) presenting at outpatient paediatric clinics. We used BoneXpert software to determine bone quality, expressed as paediatric bone index and bone age. Regarding feasibility, we successfully obtained a paediatric bone index in 60 children (63.2%). The results on bone quality showed a mean paediatric bone index standard deviation score of -1.85, significantly lower than that of healthy peers (P < 0.0001). Almost 50% of the children had severely diminished bone quality. In 64% of the children bone age diverged more than 1 year from chronological age. This mostly concerned delayed bone maturation. Automated radiogrammetry is feasible for evaluating bone quality in children who have disabilities but not severe contractures. Bone quality in these children is severely diminished. Because bone maturation frequently deviated from chronological age, we recommend comparison to bone-age-related reference values. (orig.)

  19. Carbon nanohorns accelerate bone regeneration in rat calvarial bone defect

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Takao; Iizuka, Tadashi; Kanamori, Takeshi; Yokoyama, Atsuro [Department of Oral Functional Prosthodontics, Division of Oral Functional Science, Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8586 (Japan); Matsumura, Sachiko; Shiba, Kiyotaka [Division of Protein Engineering, Cancer Institute, Japanese Foundation for Cancer Research, 3-8-31, Ariake, koutou-ku, Tokyo 135-8550 (Japan); Yudasaka, Masako; Iijima, Sumio, E-mail: tkasai@den.hokudai.ac.jp [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology, Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565 (Japan)

    2011-02-11

    A recent study showed that carbon nanohorns (CNHs) have biocompatibility and possible medical uses such as in drug delivery systems. It was reported that some kinds of carbon nanomaterials such as carbon nanotubes were useful for bone formation. However, the effect of CNHs on bone tissue has not been clarified. The purpose of this study was to evaluate the effect of CNHs on bone regeneration and their possible application for guided bone regeneration (GBR). CNHs dispersed in ethanol were fixed on a porous polytetrafluoroethylene membrane by vacuum filtration. Cranial defects were created in rats and covered by a membrane with/without CNHs. At two weeks, bone formation under the membrane with CNHs had progressed more than under that without CNHs and numerous macrophages were observed attached to CNHs. At eight weeks, there was no significant difference in the amount of newly formed bone between the groups and the appearance of macrophages was decreased compared with that at two weeks. Newly formed bone attached to some CNHs directly. These results suggest that macrophages induced by CNHs are related to bone regeneration. In conclusion, the present study indicates that CNHs are compatible with bone tissue and effective as a material for GBR.

  20. Carbon nanohorns accelerate bone regeneration in rat calvarial bone defect

    Science.gov (United States)

    Kasai, Takao; Matsumura, Sachiko; Iizuka, Tadashi; Shiba, Kiyotaka; Kanamori, Takeshi; Yudasaka, Masako; Iijima, Sumio; Yokoyama, Atsuro

    2011-02-01

    A recent study showed that carbon nanohorns (CNHs) have biocompatibility and possible medical uses such as in drug delivery systems. It was reported that some kinds of carbon nanomaterials such as carbon nanotubes were useful for bone formation. However, the effect of CNHs on bone tissue has not been clarified. The purpose of this study was to evaluate the effect of CNHs on bone regeneration and their possible application for guided bone regeneration (GBR). CNHs dispersed in ethanol were fixed on a porous polytetrafluoroethylene membrane by vacuum filtration. Cranial defects were created in rats and covered by a membrane with/without CNHs. At two weeks, bone formation under the membrane with CNHs had progressed more than under that without CNHs and numerous macrophages were observed attached to CNHs. At eight weeks, there was no significant difference in the amount of newly formed bone between the groups and the appearance of macrophages was decreased compared with that at two weeks. Newly formed bone attached to some CNHs directly. These results suggest that macrophages induced by CNHs are related to bone regeneration. In conclusion, the present study indicates that CNHs are compatible with bone tissue and effective as a material for GBR.

  1. Materials

    Science.gov (United States)

    Glaessgen, Edward H.; Schoeppner, Gregory A.

    2006-01-01

    NASA Langley Research Center has successfully developed an electron beam freeform fabrication (EBF3) process, a rapid metal deposition process that works efficiently with a variety of weldable alloys. The EBF3 process can be used to build a complex, unitized part in a layer-additive fashion, although the more immediate payoff is for use as a manufacturing process for adding details to components fabricated from simplified castings and forgings or plate products. The EBF3 process produces structural metallic parts with strengths comparable to that of wrought product forms and has been demonstrated on aluminum, titanium, and nickel-based alloys to date. The EBF3 process introduces metal wire feedstock into a molten pool that is created and sustained using a focused electron beam in a vacuum environment. Operation in a vacuum ensures a clean process environment and eliminates the need for a consumable shield gas. Advanced metal manufacturing methods such as EBF3 are being explored for fabrication and repair of aerospace structures, offering potential for improvements in cost, weight, and performance to enhance mission success for aircraft, launch vehicles, and spacecraft. Near-term applications of the EBF3 process are most likely to be implemented for cost reduction and lead time reduction through addition of details onto simplified preforms (casting or forging). This is particularly attractive for components with protruding details that would require a significantly large volume of material to be machined away from an oversized forging, offering significant reductions to the buy-to-fly ratio. Future far-term applications promise improved structural efficiency through reduced weight and improved performance by exploiting the layer-additive nature of the EBF3 process to fabricate tailored unitized structures with functionally graded microstructures and compositions.

  2. Bone sialoprotein and osteopontin in bone metastasis of osteotropic cancers.

    Science.gov (United States)

    Kruger, Thomas E; Miller, Andrew H; Godwin, Andrew K; Wang, Jinxi

    2014-02-01

    The mechanisms underlying malignant cell metastasis to secondary sites such as bone are complex and no doubt multifactorial. Members of the small integrin-binding ligand N-linked glycoproteins (SIBLINGs) family, particularly bone sialoprotein (BSP) and osteopontin (OPN), exhibit multiple activities known to promote malignant cell proliferation, detachment, invasion, and metastasis of several osteotropic cancers. The expression level of BSP and OPN is elevated in a variety of human cancers, particularly those that metastasize preferentially to the skeleton. Recent studies suggest that the "osteomimicry" of malignant cells is not only conferred by transmembrane receptors bound by BSP and OPN, but includes the "switch" in gene expression repertoire typically expressed in cells of skeletal lineage. Understanding the role of BSP and OPN in tumor progression, altered pathophysiology of bone microenvironment, and tumor metastasis to bone will likely result in development of better diagnostic approaches and therapeutic regimens for osteotropic malignant diseases.

  3. Bone pain

    DEFF Research Database (Denmark)

    Frost, Charlotte Ørsted; Hansen, Rikke Rie; Heegaard, Anne-Marie

    2016-01-01

    Skeletal conditions are common causes of chronic pain and there is an unmet medical need for improved treatment options. Bone pain is currently managed with disease modifying agents and/or analgesics depending on the condition. Disease modifying agents affect the underlying pathophysiology...... of the disease and reduce as a secondary effect bone pain. Antiresorptive and anabolic agents, such as bisphosphonates and intermittent parathyroid hormone (1-34), respectively, have proven effective as pain relieving agents. Cathepsin K inhibitors and anti-sclerostin antibodies hold, due to their disease...... modifying effects, promise of a pain relieving effect. NSAIDs and opioids are widely employed in the treatment of bone pain. However, recent preclinical findings demonstrating a unique neuronal innervation of bone tissue and sprouting of sensory nerve fibers open for new treatment possibilities....

  4. Bone graft

    Science.gov (United States)

    ... around the area. The bone graft can be held in place with pins, plates, or screws. Why ... Orthopaedic Surgery, San Francosco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the ...

  5. 口腔修复膜材料在牙种植中引导骨再生中的应用%Clinical Observation of Dental Restorations Membrane Materials in the Application of Dental Implants in Guided Bone Regeneration

    Institute of Scientific and Technical Information of China (English)

    吴喆; 王涛

    2015-01-01

    目的:观察口腔修复膜材料在牙种植中引导骨再生中的应用效果及安全性。方法:选择行牙种植再生的患者106例,按照随机数字对照表法平均分为两组,对照组(53例)采用钛膜引导骨再生,研究组(53例)采用海奥口腔修复膜引导骨再生,观察两组修复成功率及1周骨厚度、植骨厚度,并评价安全性。结果:研究组修复成功率为94.3%,明显高于对照组的83.0%,差异有统计学意义(P<0.05)。研究组患者1周骨厚度和植骨厚度均显著高于对照组,差异有统计学意义(P<0.05)。研究组不良反应发生率为3.8%,明显低于对照组的13.2%,差异有统计学意义(P<0.05)。结论:海奥口腔修复膜在牙种植中引导骨再生中效果良好,修复成功率高,有效促进骨和植骨的发育,值得临床推广和普及。%Objective:To observe clinical of dental restorations membrane materials in the application of dental implants in guided bone regeneration.Method:Teeth plant regeneration of 106 patients were selected and divided into two groups according to random number table method, control group (53 cases) used titanium membrane guided bone regeneration, reserach group (53 cases) used the oral repair membrane guided bone regeneration,Repair success rate and 1 week bone thickness, thickness of bone graft, and evaluation of safety of two groups was observed.Result: The repair success rate of reserach group was 94.3%, significantly higher than 83.0% of the control group, (P<0.05). The 1 week bone thickness and thickness of the bone graft of reserach group were significantly higher than that of control group (P<0.05).The incidence of adverse reactions of reserach group was 3.8%, significantly lower than 13.2% of the control group,there was statistically significant difference(P<0.05).Conclusion:The haiao dental restorations membrane guided bone regeneration in the dental implants is good effect, and

  6. The effect of permanent grafting materials on the preservation of the buccal bone plate after tooth extraction: an experimental study in the dog.

    LENUS (Irish Health Repository)

    Bashara, Haitham

    2012-08-01

    The aim of the present study was to evaluate the effects of a novel bone substitute system (Natix(®)), consisting of porous titanium granules (PTG) and a bovine-derived xenograft (Bio-Oss(®)), on hard tissue remodelling following their placement into fresh extraction sockets in dogs.

  7. Characterization of bone quality in prostate cancer bone metastases using Raman spectroscopy

    Science.gov (United States)

    Bi, Xiaohong; Patil, Chetan; Morrissey, Colm; Roudier, Martine P.; Mahadevan-Jansen, Anita; Nyman, Jeffry

    2010-02-01

    Prostate cancer is the most common primary tumor in men, with a high propensity to metastasize to bone. Bone metastases in prostate cancer are associated with active pathologic bone remodeling, leading to increased mortality and morbidity. Detailed characterization of bone metastases is important in the management of prostate cancer. Raman spectroscopy was applied in this study to investigate the structure and composition of metastatic bone in prostate cancer with the ultimate goal of identifying spectral features that are related to the alterations in bone quality as the bone metastases develop. Osteoblastic-, osteolytic- and tumor-absent bone specimens from prostate cancer patients were investigated using bench-top Raman microspectroscopy. Raman derived measurements of collagen mineralization, mineral crystallinity, and carbonate substitution were calculated. The osteolytic lesions demonstrated significantly lower collagen mineralization, determined by phosphate ν1/proline, and higher carbonate substitution than normal and osteoblastic bones. Mineral crystallinity was significantly lower in both blastic and lytic specimens. In addition, a significant increase in the ratio of hydroxyproine: proline was observed in the osteoblastic specimen, indicating an increase in the content of hydroxyproline at the blastic lesions. This study demonstrate that Raman spectroscopy shows promise in determining alterations in osteoblastic and osteolytic bone metastases as well as assessing the response of metastatic bone to therapies.

  8. Low Bone Density

    Science.gov (United States)

    ... Information › Bone Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your ... compared to people with normal bone density. Detecting Low Bone Density A bone density test will determine ...

  9. Tusk or Bone? An Example of Ivory Substitute in the Wildlife Trade

    Directory of Open Access Journals (Sweden)

    Margaret E. Sims

    2011-08-01

    Full Text Available Bone carvings (and other ivory substitutes are common in the modern-day lucrative international ivory trade.  Souvenirs for unknowing travelers and market shoppers can be made of non-biological material (plastic "ivory" beads or skillfully crafted natural objects made to resemble something other than their true origin.  Many of these items are received at the U. S. National Fish and Wildlife Forensics Laboratory (NFWFL for species identification as part of law enforcement investigations.  Morphologists at the Lab often receive uniquely carved ivory items that have been imported with little or no documentation.  In recent years, analysts examined several purported ivory tusks suspected to be walrus, a protected marine mammal.  After examination, the Lab determined their origin as carved leg bones of cattle using principles and methods of zooarchaeology and ancient DNA analysis.  The naturally long and straight ungulate metapodials had been cut, carved, filled, stained, and polished to closely resemble unmodified ivory tusks.  Morphological species identification of these bones proved to be a challenge since diagnostic characters of the bones had been altered and country of origin was unknown. Genetic analysis showed that the bones originated from cattle.  While bone is commonly used as a substitute for ivory, this style of artifact was not previously documented in the wildlife trade prior to our analysis.  Archaeological ethnobiologists commonly encounter bone tools and other forms of material culture from prehistoric and historic contexts; in this case bone tools come from a modern context, thus the application of methods common in zooarchaeology are situated in wildlife forensics.  In addition, results reported here pertain to cross-cultural ivory trade and conservation science.

  10. Stable Incretin Mimetics Counter Rapid Deterioration of Bone Quality in Type 1 Diabetes Mellitus.

    Science.gov (United States)

    Mansur, Sity Aishah; Mieczkowska, Aleksandra; Bouvard, Béatrice; Flatt, Peter R; Chappard, Daniel; Irwin, Nigel; Mabilleau, Guillaume

    2015-12-01

    Type 1 diabetes mellitus is associated with a high risk for bone fractures. Although bone mass is reduced, bone quality is also dramatically altered in this disorder. However, recent evidences suggest a beneficial effect of the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) pathways on bone quality. The aims of the present study were to conduct a comprehensive investigation of bone strength at the organ and tissue level; and to ascertain whether enzyme resistant GIP or GLP-1 mimetic could be beneficial in preventing bone fragility in type 1 diabetes mellitus. Streptozotocin-treated mice were used as a model of type 1 diabetes mellitus. Control and streptozotocin-diabetic animals were treated for 21 days with an enzymatic-resistant GIP peptide ([D-Ala(2) ]GIP) or with liraglutide (each at 25 nmol/kg bw, ip). Bone quality was assessed at the organ and tissue level by microCT, qXRI, 3-point bending, qBEI, nanoindentation, and Fourier-transform infrared microspectroscopy. [D-Ala2]GIP and liraglutide treatment did prevent loss of whole bone strength and cortical microstructure in the STZ-injected mice. However, tissue material properties were significantly improved in STZ-injected animals following treatment with [D-Ala2]GIP or liraglutide. Treatment of STZ-diabetic mice with [D-Ala(2) ]GIP or liraglutide was capable of significantly preventing deterioration of the quality of the bone matrix. Further studies are required to further elucidate the molecular mechanisms involved and to validate whether these findings can be translated to human patients.

  11. Early diagenesis and recrystallization of bone

    Science.gov (United States)

    Keenan, Sarah W.; Engel, Annette Summers

    2017-01-01

    One of the most challenging problems in paleobiology is determining how bone transforms from a living tissue into a fossil. The geologic record is replete with vertebrate fossils preserved from a range of depositional environments, including wetland systems. However, thermodynamic models suggest that bone (modeled as hydroxylapatite) is generally unstable in a range of varying geochemical conditions and should readily dissolve if it does not alter to a more thermodynamically stable phase, such as a fluorine-enriched apatite. Here, we assess diagenesis of alligator bone from fleshed, articulated skeletons buried in wetland soils and from de-fleshed bones in experimental mesocosms with and without microbial colonization. When microbial colonization of bone was inhibited, bioapatite recrystallization to a more stable apatite phase occurred after one month of burial. Ca-Fe-phosphate phases in bone developed after several months to years due to ion substitutions from the protonation of the hydroxyl ion. These rapid changes demonstrate a continuum of structural and bonding transformations to bone that have not been observed previously. When bones were directly in contact with sediment and microbial cells, rapid bioerosion and compositional alteration occurred after one week, but slowed after one month because biofilms reduced exposed surfaces and subsequent bioapatite lattice substitutions. Microbial contributions are likely essential in forming stable apatite phases during early diagenesis and for enabling bone preservation and fossilization.

  12. Preferential preservation of noncollagenous protein during bone diagenesis: Implications for chronometric and stable isotopic measurements

    Science.gov (United States)

    Masters, Patricia M.

    1987-12-01

    Preferential preservation of noncollagenous proteins (NCP) in diagenetically altered bone will affect amino acid compositions, inflate D/L aspartic acid ratios, and increase C/N ratios. Human skeletal remains representing both well preserved (collagenous) and diagenetically altered (noncollagenous) bones were selected from several southern California coastal archaeological sites that date from 8400 to 4100 years B.P. Amino acid compositions of the poorly preserved samples resembled NCP, which are probably retained by adsorption to the hydroxyapatite mineral phase of bone whereas collagen is degraded and lost to the environment over time. Since the racemization rate of aspartic acid in NCP is an order of magnitude faster than in collagen, the conservation of NCP in diagenetically altered bone can explain the high D/L aspartic acid ratios, and the erroneous Upper Pleistocene racemization ages calculated from these ratios, for several California Indian burials. Amino acid compositional analyses also indicated a non-amino acid source of nitrogen in the poorly preserved samples, which may account for their lower C/N ratios despite the acidic amino acid profiles typical of NCP. Preservation of NCP rather than collagen also precludes the extraction of a gelatin residue for radiocarbon dating and stable isotope analyses, but remnant NCP can yield apparently accurate radiocarbon dates. As collagen and phosphoprotein purified from a sample of modern human dentin have the same δ 13C and δ 15N values, remnant NCP may also be useful for paleodiet reconstructions based on stable carbon and nitrogen isotope compositions. Dentin collagen appears to be more resistant to diagenetic changes than does bone collagen. Consequently, dentin promises to be a more reliable material than bone for chronometric and stable isotope measurements.

  13. Bone marrow transplant

    Science.gov (United States)

    Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; Umbilical ...

  14. Electrophoretic deposition of organic/inorganic composite coatings on metallic substrates for bone replacement applications: mechanisms and development of new bioactive materials based on polysaccharides

    OpenAIRE

    Cordero Arias, Luis Eduardo

    2015-01-01

    Regarding the need to improve the usually encountered osteointegration of metallic implants with the surrounding body tissue in bone replacement applications, bioactive organic/inorganic composite coatings on metallic substrates were developed in this work using electrophoretic deposition (EPD) as coating technology. In the present work three polysaccharides, namely alginate, chondroitin sulfate and chitosan were used as the organic part, acting as the matrix of the coating and enabling the c...

  15. Characterization of silane coated hollow sphere alumina-reinforced ultra high molecular weight polyethylene composite as a possible bone substitute material

    Indian Academy of Sciences (India)

    S Roy; S Pal

    2002-12-01

    Silane coated hollow sphere alumina ceramic particles were moulded with ultra high molecular weight polyethylene (UHMWPE) to form a series of composites with alumina weight percent in the range from 15 to 50. The composites were prepared in a cyl