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Sample records for altered bone material

  1. Alteration of the bone tissue material properties in type 1 diabetes mellitus: A Fourier transform infrared microspectroscopy study.

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    Mieczkowska, Aleksandra; Mansur, Sity Aishah; Irwin, Nigel; Flatt, Peter R; Chappard, Daniel; Mabilleau, Guillaume

    2015-07-01

    Type 1 diabetes mellitus (T1DM) is a severe disorder characterized by hyperglycemia and hypoinsulinemia. A higher occurrence of bone fractures has been reported in T1DM, and although bone mineral density is reduced in this disorder, it is also thought that bone quality may be altered in this chronic pathology. Vibrational microscopies such as Fourier transform infrared microspectroscopy (FTIRM) represent an interesting approach to study bone quality as they allow investigation of the collagen and mineral compartment of the extracellular matrix in a specific bone location. However, as spectral feature arising from the mineral may overlap with those of the organic component, the demineralization of bone sections should be performed for a full investigation of the organic matrix. The aims of the present study were to (i) develop a new approach, based on the demineralization of thin bone tissue section to allow a better characterization of the bone organic component by FTIRM, (ii) to validate collagen glycation and collagen integrity in bone tissue and (iii) to better understand what alterations of tissue material properties in newly forming bone occur in T1DM. The streptozotocin-injected mouse (150 mg/kg body weight, injected at 8 weeks old) was used as T1DM model. Animals were randomly allocated to control (n = 8) or diabetic (n = 10) groups and were sacrificed 4 weeks post-STZ injection. Bones were collected at necropsy, embedded in polymethylmethacrylate and sectioned prior to examination by FTIRM. FTIRM collagen parameters were collagen maturity (area ratio between 1660 and 1690 cm(-1) subbands), collagen glycation (area ratio between the 1032 cm(-1) subband and amide I) and collagen integrity (area ratio between the 1338 cm(-1) subband and amide II). No significant differences in the mineral compartment of the bone matrix could be observed between controls and STZ-injected animals. On the other hand, as compared with controls, STZ-injected animals presented with

  2. Bone material strength index as measured by impact microindentation is altered in patients with acromegaly.

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    Malgo, F; Hamdy, N A T; Rabelink, T J; Kroon, H M; Claessen, K M J A; Pereira, A M; Biermasz, N R; Appelman-Dijkstra, N M

    2017-03-01

    Acromegaly is a rare disease caused by excess growth hormone (GH) production by the pituitary adenoma. The skeletal complications of GH and IGF-1 excess include increased bone turnover, increased cortical bone mass and deteriorated microarchitecture of trabecular bone, associated with a high risk of vertebral fractures in the presence of relatively normal bone mineral density (BMD). We aimed to evaluate tissue-level properties of bone using impact microindentation (IMI) in well-controlled patients with acromegaly aged ≥18 years compared to 44 controls from the outpatient clinic of the Centre for Bone Quality. In this cross-sectional study, bone material strength index (BMSi) was measured in 48 acromegaly patients and 44 controls with impact microindentation using the osteoprobe. Mean age of acromegaly patients (54% male) was 60.2 years (range 37.9-76.5), and 60.5 years (range 39.8-78.6) in controls (50% male). Patients with acromegaly and control patients had comparable BMI (28.2 kg/m 2  ± 4.7 vs 26.6 kg/m 2  ± 4.3, P = 0.087) and comparable BMD at the lumbar spine (1.04 g/cm 2  ± 0.21 vs 1.03 g/cm 2  ± 0.13, P = 0.850) and at the femoral neck (0.84 g/cm 2  ± 0.16 vs 0.80 g/cm 2  ± 0.09, P = 0.246). BMSi was significantly lower in acromegaly patients than that in controls (79.4 ± 0.7 vs 83.2 ± 0.7; P acromegaly after reversal of long-term exposure to pathologically high GH and IGF-1 levels. Our findings also suggest that methods other than DXA should be considered to evaluate bone fragility in patients with acromegaly. © 2017 European Society of Endocrinology.

  3. Edentulation alters material properties of cortical bone in the human craniofacial skeleton: functional implications for craniofacial structure in primate evolution

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    Dechow, Paul C.; Wang, Qian; Peterson, Jill

    2011-01-01

    Skeletal adaptations to reduced function are an important source of skeletal variation and may be indicative of environmental pressures that lead to evolutionary changes. Humans serve as a model animal to investigate the effects of loss of craniofacial function through edentulation. In the human maxilla, it is known that edentulation leads to significant changes in skeletal structure such as residual ridge resorption and loss of cortical thickness. However, little is known about changes in bone tissue structure and material properties, which are also important for understanding skeletal mechanics but are often ignored. The aims of this study were to determine cortical material properties in edentulous crania and to evaluate differences with dentate crania and thus examine the effects of loss of function on craniofacial structure. Cortical bone samples from fifteen edentulous human skulls were measured for thickness and density. Elastic properties and directions of maximum stiffness were determined by using ultrasonic techniques. These data were compared to those from dentate crania reported in a previous investigation. Cortical bone from all regions of the facial skeleton of edentulous individuals is thinner than in dentate skulls. Elastic and shear moduli, and density are similar or greater in the zygoma and cranial vault of edentulous individuals, while these properties are less in the maxilla. Most cortical bone, especially in edentulous maxillae, has reduced directional orientation. The loss of significant occlusal loads following edentulation may contribute to the change in material properties and the loss of orientation over time during the normal process of bone remodeling. These results suggest that area-specific cortical microstructural changes accompany bone resorption following edentulation. They also suggest that functional forces are important for maintaining bone mass throughout the craniofacial skeleton, even in areas such as the browridges, which

  4. Bone alterations by stress in athletes

    International Nuclear Information System (INIS)

    Doege, H.

    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.) [de

  5. Alterations to the subchondral bone architecture during osteoarthritis : bone adaptation versus endochondral bone formation

    NARCIS (Netherlands)

    Cox, L.G.E.; Donkelaar, van C.C.; Rietbergen, van B.; Emans, P.J.; Ito, K.

    2013-01-01

    Objective Osteoarthritis (OA) is characterized by loss of cartilage and alterations in subchondral bone architecture. Changes in cartilage and bone tissue occur simultaneously and are spatially correlated, indicating that they are probably related. We investigated two hypotheses regarding this

  6. Megakaryocytic alterations in thrombocytopenia: A bone marrow aspiration study

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    Muhury Manas

    2009-10-01

    Full Text Available Context: Dysplastic changes are well documented in myelodysplastic syndromes (MDS. However, they are also observed in non-MDS hematological conditions. Aims: To evaluate the megakaryocytic alterations in the bone marrow aspirations in cases of non-MDS related thrombocytopenia. Setting and Design: A prospective study of 144 bone marrow aspirates was conducted in the department of pathology, Kasturba Medical College, Mangalore. The aspirates were studied to assess the number and morphology of the megakaryocytes in non-MDS related thrombocytopenia and evaluate their significance when compared to changes in MDS. Materials and Methods: The bone marrow aspiration smears were stained with Leishman stain and examined under light microscope. Statistical Analysis Used: Fisher′s exact test. A P value less than 0.05 was considered significant. Sensitivity and specificity was calculated for those features which were significant in the relevant hematological disorders. Results: The sensitivity of immature megakaryocytes, dysplastic forms and micromegakaryocytes in cases of immune thrombocytopenic purpura was 100%, 89% and 42% respectively. The specificity of emperipolesis was 74%. In cases of infection-associated thrombocytopenia, immature megakaryocytes had a sensitivity of 100% and cytoplasmic vacuolization were 86% specific. The sensitivity of the dysplastic forms in megaloblastic anemia was 75%. However, no platelet budding was observed. The presence of micromegakaryocyte had a specificity of 83% in MDS, and was statistically significant when compared to cases of non-MDS conditions (P< 0.05. Conclusions: Careful understanding of the morphological changes of megakaryocytes in bone marrow aspirates can improve the diagnostic accuracy for a wide range of hematological disorders thereby enabling proper therapeutic interventions.

  7. Alteration In Bones Metabolism In Active Rheumatoid Arthritis

    International Nuclear Information System (INIS)

    Salem, E.S.

    2013-01-01

    The strength and integrity of the human skeleton depends on a delicate equilibrium between bone resorption and bone formation. Osteocalcin (OC) is synthesized by osteoblasts and is considered to be a marker of bone formation and helps in corporating calcium into bone tissue. Rheumatoid arthritis (RA) is an autoimmune inflammatory joint disease characterized by bone complication including bone pain, erosion and osteoporosis. The aim of the present study is to evaluate some factors responsible in bone metabolism termed OC, vitamin D (vit. D), oncostatin M (OSM), ionized calcium and alkaline phosphatase. Fifty pre-menopausal female patients with active RA and twenty healthy controls of the same age were included in the present study. Radioimmunoassay (RIA) was used to estimate serum OC and active vitamin D. The quantitative determination of ionized calcium and alkaline phosphatase were carried out colorimetrically. OSM was measured by ELISA and serum levels of OC and active vitamin D were significantly decreased in RA patients as compared to those of the control group. On the other hand, the levels of serum OSM, ionized calcium and alkaline phosphatase were significantly increased in the RA patients as compared to their healthy control subjects. The results of this study indicated that early investigation and therapy of disturbances of bone metabolism in active RA are necessary for better prognosis and exhibited the importance of OC as a diagnostic tool of alterations of bone metabolism in RA patients.

  8. Advances in Osteobiologic Materials for Bone Substitutes.

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    Hasan, Anwarul; Byambaa, Batzaya; Morshed, Mahboob; Cheikh, Mohammad Ibrahim; Shakoor, Rana Abdul; Mustafy, Tanvir; Marei, Hany

    2018-04-27

    A significant challenge in the current orthopedics is the development of suitable osteobiologic materials that can replace the conventional allografts, autografts and xenografts, and thereby serve as implant materials as bone substitutes for bone repair or remodeling. The complex biology behind the nano-microstructure of bones and their repair mechanisms, which involve various types of chemical and biomechanical signaling amongst different cells, has set strong requirements for biomaterials to be used in bone tissue engineering. This review presents an overview of various types of osteobiologic materials to facilitate the formation of the functional bone tissue and healing of the bone, covering metallic, ceramic, polymeric and cell-based graft substitutes, as well as some biomolecular strategies including stem cells, extracellular matrices, growth factors and gene therapies. Advantages and disadvantages of each type, particularly from the perspective of osteoinductive and osteoconductive capabilities, are discussed. Although the numerous challenges of bone regeneration in tissue engineering and regenerative medicine are yet to be entirely addressed, further advancements in osteobiologic materials will pave the way towards engineering fully functional bone replacement grafts. This article is protected by copyright. All rights reserved.

  9. Biomimetic materials for controlling bone cell responses.

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    Drevelle, Olivier; Faucheux, Nathalie

    2013-01-01

    Bone defects that cannot "heal spontaneously during life" will become an ever greater health problem as populations age. Harvesting autografts has several drawbacks, such as pain and morbidity at both donor and acceptor sites, the limited quantity of material available, and frequently its inappropriate shape. Researchers have therefore developed alternative strategies that involve biomaterials to fill bone defects. These biomaterials must be biocompatible and interact with the surrounding bone tissue to allow their colonization by bone cells and blood vessels. The latest generation biomaterials are not inert; they control cell responses like adhesion, proliferation and differentiation. These biomaterials are called biomimetic materials. This review focuses on the development of third generation materials. We first briefly describe the bone tissue with its cells and matrix, and then how bone cells interact with the extracellular matrix. The next section covers the materials currently used to repair bone defects. Finally, we describe the strategies employed to modify the surface of materials, such as coating with hydroxyapatite and grafting biomolecules.

  10. Stress and Alterations in Bones: An Interdisciplinary Perspective

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    Pia-Maria Wippert

    2017-05-01

    Full Text Available Decades of research have demonstrated that physical stress (PS stimulates bone remodeling and affects bone structure and function through complex mechanotransduction mechanisms. Recent research has laid ground to the hypothesis that mental stress (MS also influences bone biology, eventually leading to osteoporosis and increased bone fracture risk. These effects are likely exerted by modulation of hypothalamic–pituitary–adrenal axis activity, resulting in an altered release of growth hormones, glucocorticoids and cytokines, as demonstrated in human and animal studies. Furthermore, molecular cross talk between mental and PS is thought to exist, with either synergistic or preventative effects on bone disease progression depending on the characteristics of the applied stressor. This mini review will explain the emerging concept of MS as an important player in bone adaptation and its potential cross talk with PS by summarizing the current state of knowledge, highlighting newly evolving notions (such as intergenerational transmission of stress and its epigenetic modifications affecting bone and proposing new research directions.

  11. Altered thermogenesis and impaired bone remodeling in Misty mice.

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    Motyl, Katherine J; Bishop, Kathleen A; DeMambro, Victoria E; Bornstein, Sheila A; Le, Phuong; Kawai, Masanobu; Lotinun, Sutada; Horowitz, Mark C; Baron, Roland; Bouxsein, Mary L; Rosen, Clifford J

    2013-09-01

    Fat mass may be modulated by the number of brown-like adipocytes in white adipose tissue (WAT) in humans and rodents. Bone remodeling is dependent on systemic energy metabolism and, with age, bone remodeling becomes uncoupled and brown adipose tissue (BAT) function declines. To test the interaction between BAT and bone, we employed Misty (m/m) mice, which were reported be deficient in BAT. We found that Misty mice have accelerated age-related trabecular bone loss and impaired brown fat function (including reduced temperature, lower expression of Pgc1a, and less sympathetic innervation compared to wild-type (+/ +)). Despite reduced BAT function, Misty mice had normal core body temperature, suggesting heat is produced from other sources. Indeed, upon acute cold exposure (4°C for 6 hours), inguinal WAT from Misty mice compensated for BAT dysfunction by increasing expression of Acadl, Pgc1a, Dio2, and other thermogenic genes. Interestingly, acute cold exposure also decreased Runx2 and increased Rankl expression in Misty bone, but only Runx2 was decreased in wild-type. Browning of WAT is under the control of the sympathetic nervous system (SNS) and, if present at room temperature, could impact bone metabolism. To test whether SNS activity could be responsible for accelerated trabecular bone loss, we treated wild-type and Misty mice with the β-blocker, propranolol. As predicted, propranolol slowed trabecular bone volume/total volume (BV/TV) loss in the distal femur of Misty mice without affecting wild-type. Finally, the Misty mutation (a truncation of DOCK7) also has a significant cell-autonomous role. We found DOCK7 expression in whole bone and osteoblasts. Primary osteoblast differentiation from Misty calvaria was impaired, demonstrating a novel role for DOCK7 in bone remodeling. Despite the multifaceted effects of the Misty mutation, we have shown that impaired brown fat function leads to altered SNS activity and bone loss, and for the first time that cold

  12. Multifunctional materials for bone cancer treatment

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    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

  13. Methionine restriction alters bone morphology and affects osteoblast differentiation

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    Amadou Ouattara

    2016-12-01

    Full Text Available Methionine restriction (MR extends the lifespan of a wide variety of species, including rodents, drosophila, nematodes, and yeasts. MR has also been demonstrated to affect the overall growth of mice and rats. The objective of this study was to evaluate the effect of MR on bone structure in young and aged male and female C57BL/6J mice. This study indicated that MR affected the growth rates of males and young females, but not aged females. MR reduced volumetric bone mass density (vBMD and bone mineral content (BMC, while bone microarchitecture parameters were decreased in males and young females, but not in aged females compared to control-fed (CF mice. However, when adjusted for bodyweight, the effect of MR in reducing vBMD, BMC and microarchitecture measurements was either attenuated or reversed suggesting that the smaller bones in MR mice is appropriate for its body size. In addition, CF and MR mice had similar intrinsic strength properties as measured by nanoindentation. Plasma biomarkers suggested that the low bone mass in MR mice could be due to increased collagen degradation, which may be influenced by leptin, IGF-1, adiponectin and FGF21 hormone levels. Mouse preosteoblast cell line cultured under low sulfur amino acid growth media attenuated gene expression levels of Col1al, Runx2, Bglap, Alpl and Spp1 suggesting delayed collagen formation and bone differentiation. Collectively, our studies revealed that MR altered bone morphology which could be mediated by delays in osteoblast differentiation. Keywords: Methionine restriction, Aged mice, Micro-computed tomography, Nanoindentation, MC3T3-E1 subclone 4

  14. 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.

  15. Piezoelectric materials as stimulatory biomedical materials and scaffolds for bone repair.

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    Tandon, Biranche; Blaker, Jonny J; Cartmell, Sarah H

    2018-04-16

    The process of bone repair and regeneration requires multiple physiological cues including biochemical, electrical and mechanical - that act together to ensure functional recovery. Myriad materials have been explored as bioactive scaffolds to deliver these cues locally to the damage site, amongst these piezoelectric materials have demonstrated significant potential for tissue engineering and regeneration, especially for bone repair. Piezoelectric materials have been widely explored for power generation and harvesting, structural health monitoring, and use in biomedical devices. They have the ability to deform with physiological movements and consequently deliver electrical stimulation to cells or damaged tissue without the need of an external power source. Bone itself is piezoelectric and the charges/potentials it generates in response to mechanical activity are capable of enhancing bone growth. Piezoelectric materials are capable of stimulating the physiological electrical microenvironment, and can play a vital role to stimulate regeneration and repair. This review gives an overview of the association of piezoelectric effect with bone repair, and focuses on state-of-the-art piezoelectric materials (polymers, ceramics and their composites), the fabrication routes to produce piezoelectric scaffolds, and their application in bone repair. Important characteristics of these materials from the perspective of bone tissue engineering are highlighted. Promising upcoming strategies and new piezoelectric materials for this application are presented. Electrical stimulation/electrical microenvironment are known effect the process of bone regeneration by altering the cellular response and are crucial in maintaining tissue functionality. Piezoelectric materials, owing to their capability of generating charges/potentials in response to mechanical deformations, have displayed great potential for fabricating smart stimulatory scaffolds for bone tissue engineering. The growing

  16. Method and apparatus for altering material

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    Stinnett, Regan W.; Greenly, John B.

    2002-02-05

    Methods and apparatus for thermally altering the near surface characteristics of a material are described. In particular, a repetitively pulsed ion beam system comprising a high energy pulsed power source and an ion beam generator are described which are capable of producing single species high voltage ion beams (0.25-2.5 MeV) at 1-1000 kW average power and over extended operating cycles (10.sup.8). Irradiating materials with such high energy, repetitively pulsed ion beams can yield surface treatments including localized high temperature anneals to melting, both followed by rapid thermal quenching to ambient temperatures to achieve both novel and heretofore commercially unachievable physical characteristics in a near surface layer of material.

  17. Osteoarthritis alters the patellar bones subchondral trabecular architecture.

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    Hoechel, Sebastian; Deyhle, Hans; Toranelli, Mireille; Müller-Gerbl, Magdalena

    2017-09-01

    Following the principles of "morphology reveals biomechanics," the cartilage-osseous interface and the trabecular network show defined adaptation in response to physiological loading. In the case of a compromised relationship, the ability to support the load diminishes and the onset of osteoarthritis (OA) may arise. To describe and quantify the changes within the subchondral bone plate (SBP) and trabecular architecture, 10 human OA patellae were investigated by CT and micro-CT. The results are presented in comparison to a previously published dataset of 10 non-OA patellae which were evaluated in the same manner. The analyzed OA samples showed no distinctive mineralization pattern in regards to the physiological biomechanics, but a highly irregular disseminated distribution. In addition, no regularity in bone distribution and architecture across the trabecular network was found. We observed a decrease of material as the bone volume and trabecular thickness/number were significantly reduced. In comparison to non-OA samples, greatest differences for all parameters were found within the first mm of trabecular bone. The differences decreased toward the fifth mm in a logarithmic manner. The interpretation of the logarithmic relation leads to the conclusion that the main impact of OA on bony structures is located beneath the SBP and lessens with depth. In addition to the clear difference in material with approximately 12% less bone volume in the first mm in OA patellae, the architectural arrangement is more rod-like and isotropic, accounting for an architectural decrease in stability and support. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1982-1989, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

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

    International Nuclear Information System (INIS)

    Herlin, Maria; Finnilä, Mikko A.J.; Zioupos, Peter; Aula, Antti; Risteli, Juha; Miettinen, Hanna M.; Jämsä, Timo; Tuukkanen, Juha; Korkalainen, Merja; Håkansson, Helen; Viluksela, Matti

    2013-01-01

    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 −/− ) and wild-type (Ahr +/+ ) 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 +/+ 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 −/− mice displayed a slightly modified bone phenotype as compared with untreated Ahr +/+ mice, while TCDD exposure caused only a few changes in bones of Ahr −/− 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 +/+ 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 results in increased trabecular bone

  19. 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

  20. Vitamin K2 improves femoral bone strength without altering bone mineral density in gastrectomized rats.

    Science.gov (United States)

    Iwamoto, Jun; Sato, Yoshihiro; Matsumoto, Hideo

    2014-01-01

    Gastrectomy (GX) induces osteopenia in rats. The present study examined the skeletal effects of vitamin K2 in GX rats. Thirty male Sprague-Dawley rats (12 wk old) were randomized by the stratified weight method into the following three groups of 10 animals each: sham operation (control) group; GX group; and GX+oral vitamin K2 (menatetrenone, 30 mg/kg, 5 d/wk) group. Treatment was initiated at 1 wk after surgery. After 6 wk of treatment, the bone mineral content (BMC), bone mineral density (BMD), and mechanical strength of the femoral diaphysis and distal metaphysis were determined by peripheral quantitative computed tomography and mechanical strength tests, respectively. GX induced decreases in the BMC, BMD, and ultimate force of the femoral diaphysis and distal metaphysis. Vitamin K2 did not significantly influence the BMC or BMD of the femoral diaphysis or distal metaphysis in GX rats, but attenuated the decrease in the ultimate force and increased the stiffness of the femoral diaphysis. The present study showed that administration of vitamin K2 to GX rats improved the bone strength of the femoral diaphysis without altering the BMC or BMD, suggesting effects of vitamin K2 on the cortical bone quality.

  1. A biomimetic approach toward artificial bone-like materials

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    Bertozzi, Carolyn R.

    2001-01-01

    Bone consists of microcrystalline hydroxyapatite and collagen, an elastic protein matrix that is decorated with mineral-nucleating phosphoproteins. Our rational design of artificial bone-like material uses natural bone as a guide. Hydrogel and self-assembling polymers that possess anionic groups suitably positioned for nucleating biominerals, and therefore mimic the natural function of the collagen-phosphoprotein matrix in bone, were designed to direct template-driven biomimetic mineralizatio...

  2. Biodegradable Magnesium Alloys Developed as Bone Repair Materials: A Review

    Directory of Open Access Journals (Sweden)

    Chen Liu

    2018-01-01

    Full Text Available Bone repair materials are rapidly becoming a hot topic in the field of biomedical materials due to being an important means of repairing human bony deficiencies and replacing hard tissue. Magnesium (Mg alloys are potentially biocompatible, osteoconductive, and biodegradable metallic materials that can be used in bone repair due to their in situ degradation in the body, mechanical properties similar to those of bones, and ability to positively stimulate the formation of new bones. However, rapid degradation of these materials in physiological environments may lead to gas cavities, hemolysis, and osteolysis and thus, hinder their clinical orthopedic applications. This paper reviews recent work on the use of Mg alloy implants in bone repair. Research to date on alloy design, surface modification, and biological performance of Mg alloys is comprehensively summarized. Future challenges for and developments in biomedical Mg alloys for use in bone repair are also discussed.

  3. Bionic Design, Materials and Performance of Bone Tissue Scaffolds

    Directory of Open Access Journals (Sweden)

    Tong Wu

    2017-10-01

    Full Text Available Design, materials, and performance are important factors in the research of bone tissue scaffolds. This work briefly describes the bone scaffolds and their anatomic structure, as well as their biological and mechanical characteristics. Furthermore, we reviewed the characteristics of metal materials, inorganic materials, organic polymer materials, and composite materials. The importance of the bionic design in preoperative diagnosis models and customized bone scaffolds was also discussed, addressing both the bionic structure design (macro and micro structure and the bionic performance design (mechanical performance and biological performance. Materials and performance are the two main problems in the development of customized bone scaffolds. Bionic design is an effective way to solve these problems, which could improve the clinical application of bone scaffolds, by creating a balance between mechanical performance and biological performance.

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

    Directory of Open Access Journals (Sweden)

    Abbas Jafari

    2017-02-01

    Full Text Available 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.

  5. 21 CFR 872.3930 - Bone grafting material.

    Science.gov (United States)

    2010-04-01

    ... of the oral and maxillofacial region. (b) Classification. (1) Class II (special controls) for bone grafting materials that do not contain a drug that is a therapeutic biologic. The special control is FDA's “Class II Special Controls Guidance Document: Dental Bone Grafting Material Devices.” (See § 872.1(e) for...

  6. Alterations in archaeological bones thermally treated: structure and morphology

    International Nuclear Information System (INIS)

    Pijoan, C.M.; Mansilla, J.; Leboreiro, I.; Lara, V.H.; Bosch, P.

    2004-01-01

    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

  7. Demineralized dentin matrix composite collagen material for bone tissue regeneration.

    Science.gov (United States)

    Li, Jianan; Yang, Juan; Zhong, Xiaozhong; He, Fengrong; Wu, Xiongwen; Shen, Guanxin

    2013-01-01

    Demineralized dentin matrix (DDM) had been successfully used in clinics as bone repair biomaterial for many years. However, particle morphology of DDM limited it further applications. In this study, DDM and collagen were prepared to DDM composite collagen material. The surface morphology of the material was studied by scanning electron microscope (SEM). MC3T3-E1 cells responses in vitro and tissue responses in vivo by implantation of DDM composite collagen material in bone defect of rabbits were also investigated. SEM analysis showed that DDM composite collagen material evenly distributed and formed a porous scaffold. Cell culture and animal models results indicated that DDM composite collagen material was biocompatible and could support cell proliferation and differentiation. Histological evaluation showed that DDM composite collagen material exhibited good biocompatibility, biodegradability and osteoconductivity with host bone in vivo. The results suggested that DDM composite collagen material might have a significant clinical advantage and potential to be applied in bone and orthopedic surgery.

  8. Prior ankle fractures in postmenopausal women are associated with low areal bone mineral density and bone microstructure alterations.

    Science.gov (United States)

    Biver, E; Durosier, C; Chevalley, T; Herrmann, F R; Ferrari, S; Rizzoli, R

    2015-08-01

    In a cross-sectional analysis in postmenopausal women, prior ankle fractures were associated with lower areal bone mineral density (BMD) and trabecular bone alterations compared to no fracture history. Compared to women with forearm fractures, microstructure alterations were of lower magnitude. These data suggest that ankle fractures are another manifestation of bone fragility. Whether ankle fractures represent fragility fractures associated with low areal bone mineral density (aBMD) and volumetric bone mineral density (vBMD) and/or bone microstructure alterations remains unclear, in contrast to the well-recognised association between forearm fractures and osteoporosis. The objective of this study was to investigate aBMD, vBMD and bone microstructure in postmenopausal women with prior ankle fracture in adulthood, compared with women without prior fracture or with women with prior forearm fractures, considered as typically of osteoporotic origin. In a cross-sectional analysis in the Geneva Retirees Cohort study, 63 women with ankle fracture and 59 with forearm fracture were compared to 433 women without fracture (mean age, 65 ± 1 years). aBMD was measured by dual-energy X-ray absorptiometry; distal radius and tibia vBMD and bone microstructure were measured by high-resolution peripheral quantitative computed tomography. Compared with women without fracture, those with ankle fractures had lower aBMD, radius vBMD (-7.9%), trabecular density (-10.7%), number (-7.3%) and thickness (-4.6%) and higher trabecular spacing (+14.5%) (P ankle fractures were 2.2 and 1.6, respectively, vs 2.2 and 2.7 for forearm fracture, respectively (P ≤ 0.001 for all). Compared to women with forearm fractures, those with ankle fractures had similar spine and hip aBMD, but microstructure alterations of lower magnitude. Women with ankle fractures have lower aBMD and vBMD and trabecular bone alterations, suggesting that ankle fractures are another manifestation of bone fragility.

  9. 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.).

  10. Material model of pelvic bone based on modal analysis: a study on the composite bone.

    Science.gov (United States)

    Henyš, Petr; Čapek, Lukáš

    2017-02-01

    Digital models based on finite element (FE) analysis are widely used in orthopaedics to predict the stress or strain in the bone due to bone-implant interaction. The usability of the model depends strongly on the bone material description. The material model that is most commonly used is based on a constant Young's modulus or on the apparent density of bone obtained from computer tomography (CT) data. The Young's modulus of bone is described in many experimental works with large variations in the results. The concept of measuring and validating the material model of the pelvic bone based on modal analysis is introduced in this pilot study. The modal frequencies, damping, and shapes of the composite bone were measured precisely by an impact hammer at 239 points. An FE model was built using the data pertaining to the geometry and apparent density obtained from the CT of the composite bone. The isotropic homogeneous Young's modulus and Poisson's ratio of the cortical and trabecular bone were estimated from the optimisation procedure including Gaussian statistical properties. The performance of the updated model was investigated through the sensitivity analysis of the natural frequencies with respect to the material parameters. The maximal error between the numerical and experimental natural frequencies of the bone reached 1.74 % in the first modal shape. Finally, the optimised parameters were matched with the data sheets of the composite bone. The maximal difference between the calibrated material properties and that obtained from the data sheet was 34 %. The optimisation scheme of the FE model based on the modal analysis data provides extremely useful calibration of the FE models with the uncertainty bounds and without the influence of the boundary conditions.

  11. Hormonal alterations in PCOS and its influence on bone metabolism.

    Science.gov (United States)

    Krishnan, Abhaya; Muthusami, Sridhar

    2017-02-01

    According to the World Health Organization (WHO) polycystic ovary syndrome (PCOS) occurs in 4-8% of women worldwide. The prevalence of PCOS in Indian adolescents is 12.2% according to the Indian Council of Medical Research (ICMR). The National Institute of Health has documented that it affects approximately 5 million women of reproductive age in the United States. Hormonal imbalance is the characteristic of many women with polycystic ovarian syndrome (PCOS). The influence of various endocrine changes in PCOS women and their relevance to bone remains to be documented. Hormones, which include gonadotrophin-releasing hormone (GnRH), insulin, the leutinizing/follicle-stimulating hormone (LH/FSH) ratio, androgens, estrogens, growth hormones (GH), cortisol, parathyroid hormone (PTH) and calcitonin are disturbed in PCOS women. These hormones influence bone metabolism in human subjects directly as well as indirectly. The imbalance in these hormones results in increased prevalence of osteoporosis in PCOS women. Limited evidence suggests that the drugs taken during the treatment of PCOS increase the risk of bone fracture in PCOS patients through endocrine disruption. This review is aimed at the identification of the relationship between bone mineral density and hormonal changes in PCOS subjects and identifies potential areas to study bone-related disorders in PCOS women. © 2017 Society for Endocrinology.

  12. Alterations of bone skeleton structure in connection with strontium-90 incorporation

    International Nuclear Information System (INIS)

    Rodionova, N.V.; Mazhuga, P.M.; Domashevskaya, E.I.; Gorskij, B.A.; Nakorenok, G.B.

    1994-01-01

    By using the methods of histology, electron microscopy and radiochemistry studied the bone skeleton state of animals (mouse like rodents and minks) which live in the 30 km zone of the ChNPP.It was defined contents of 90 Sr, 137 Cs, 134 Cs in the bones during 1989-1993 years. There were described changes in histostructure of the periost endost and bone compact of the tubular bones and also in metaepiphyzal growth plate. The mechanisms of the revealed alterations are discussed

  13. Marginal bone-level alterations of loaded zirconia and titanium dental implants: an experimental study in the dog mandible.

    Science.gov (United States)

    Thoma, Daniel S; Benic, Goran I; Muñoz, Fernando; Kohal, Ralf; Sanz Martin, Ignacio; Cantalapiedra, Antonio G; Hämmerle, Christoph H F; Jung, Ronald E

    2016-04-01

    The aim was to test whether or not the marginal bone-level alterations of loaded zirconia implants are similar to the bone-level alterations of a grade 4 titanium one-piece dental implant. In six dogs, all premolars and the first molars were extracted in the mandible. Four months later, three zirconia implants (BPI, VC, ZD) and a control titanium one-piece (STM) implant were randomly placed in each hemimandible and left for transmucosal healing (baseline). Six months later, CAD/CAM crowns were cemented. Sacrifice was scheduled at 6-month postloading. Digital X-rays were taken at implant placement, crowns insertion, and sacrifice. Marginal bone-level alterations were calculated, and intra- and intergroup comparisons performed adjusted by confounding factors. Implants were successfully placed. Until crown insertion, two implants were fractured (one VC, one ZD). At sacrifice, 5 more implants were (partly) fractured (one BPI, four ZD), and one lost osseointegration (VC). No decementation of crowns occurred. All implant systems demonstrated a statistically significant (except VC) loss of marginal bone between baseline and crown insertion ranging from 0.29 mm (VC; P = 0.116) to 0.80 mm (ZD; P = 0.013). The estimated marginal bone loss between baseline and 6 months of loading ranged between 0.19 mm (BPI) and 1.11 mm (VC), being statistically significant for STM and VC only (P implants and control implants (STM vs. BPI P = 0.007; vs. VC P = 0.001; vs. ZD P = 0.011). Zirconia implants were more prone to fracture prior to and after loading with implant-supported crowns compared to titanium implants. Individual differences and variability in the extent of the bone-level changes during the 12-month study period were found between the different implant types and materials. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. 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.

  15. Development of implants composed of bioactive materials for bone repair

    Science.gov (United States)

    Xiao, Wei

    The purpose of this Ph.D. research was to address the clinical need for synthetic bioactive materials to heal defects in non-loaded and loaded bone. Hollow hydroxyapatite (HA) microspheres created in a previous study were evaluated as a carrier for controlled release of bone morphogenetic protein-2 (BMP2) in bone regeneration. New bone formation in rat calvarial defects implanted with BMP2-loaded microspheres (43%) was significantly higher than microspheres without BMP2 (17%) at 6 weeks postimplantation. Then hollow HA microspheres with a carbonate-substituted composition were prepared to improve their resorption rate. Hollow HA microspheres with 12 wt. % of carbonate showed significantly higher new bone formation (73 +/- 8%) and lower residual HA (7 +/- 2%) than stoichiometric HA microspheres (59 +/- 2% new bone formation; 21 +/- 3% residual HA). The combination of carbonate-substituted hollow HA microspheres and clinically-safe doses of BMP2 could provide promising implants for healing non-loaded bone defects. Strong porous scaffolds of bioactive silicate (13-93) glass were designed with the aid of finite-element modeling, created by robocasting and evaluated for loaded bone repair. Scaffolds with a porosity gradient to mimic human cortical bone showed a compressive strength of 88 +/- 20 MPa, a flexural strength of 34 +/- 5 MPa and the ability to support bone infiltration in vivo. The addition of a biodegradable polylactic acid (PLA) layer to the external surface of these scaffolds increased their load-bearing capacity in four-point bending by 50% and dramatically enhanced their work of fracture, resulting in a "ductile" mechanical response. These bioactive glass-PLA composites, combining bioactivity, high strength, high work of fracture and an internal architecture conducive to bone infiltration, could provide optimal implants for structural bone repair.

  16. Exposure to Low-Dose X-Ray Radiation Alters Bone Progenitor Cells and Bone Microarchitecture.

    Science.gov (United States)

    Lima, Florence; Swift, Joshua M; Greene, Elisabeth S; Allen, Matthew R; Cunningham, David A; Braby, Leslie A; Bloomfield, Susan A

    2017-10-01

    Exposure to high-dose ionizing radiation during medical treatment exerts well-documented deleterious effects on bone health, reducing bone density and contributing to bone growth retardation in young patients and spontaneous fracture in postmenopausal women. However, the majority of human radiation exposures occur in a much lower dose range than that used in the radiation oncology clinic. Furthermore, very few studies have examined the effects of low-dose ionizing radiation on bone integrity and results have been inconsistent. In this study, mice were irradiated with a total-body dose of 0.17, 0.5 or 1 Gy to quantify the early (day 3 postirradiation) and delayed (day 21 postirradiation) effects of radiation on bone microarchitecture and bone marrow stromal cells (BMSCs). Female BALBc mice (4 months old) were divided into four groups: irradiated (0.17, 0.5 and 1 Gy) and sham-irradiated controls (0 Gy). Micro-computed tomography analysis of distal femur trabecular bone from animals at day 21 after exposure to 1 Gy of X-ray radiation revealed a 21% smaller bone volume (BV/TV), 22% decrease in trabecular numbers (Tb.N) and 9% greater trabecular separation (Tb.Sp) compared to sham-irradiated controls (P X-rays, whereas osteoclastogenesis was enhanced. A better understanding of the effects of radiation on osteoprogenitor cell populations could lead to more effective therapeutic interventions that protect bone integrity for individuals exposed to low-dose ionizing radiation.

  17. Development of a piezoelectric bone substitute material

    International Nuclear Information System (INIS)

    Al-Bader, Yousef 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 coefficient (d) in the axial direction was obtained as a function of the percent barium titanate added. The development of piezoelectricity when barium titanate is added was interpreted, using XRD, as due to the formation of barium titanate silicate. Compositions determined as having properties comparable to those of natural bone, were tested for in vitro solubility in pure water and saline solution. The results obtained showed that the selected composition (containing 15% kaolin, 10% barium titanate, pressed at 35 MPa and fired at 1350 degC for two hours) has properties comparable to those of dry bone and a reasonable in vitro solubility. (author)

  18. Value of skeletal scintiscanning in cases of primary bone tumours and tumourous alterations

    International Nuclear Information System (INIS)

    Sokolowski, U.

    1982-01-01

    In the course of an investigation on the storage behaviour of primary bone tumours and tumourous bone alterations the skeletal scintigrams of a total of 26 patients were evaluated. Bone scintiscanning was done according to current practice after injection of an average amount of 10mCi sup(99m)Tc-MDP, followed by a semiquantitative evaluation. In all cases of malignant bone tumours there was fond to be increased storage of radionuclide; with benign bone alterations this was so in 70 per cent of cases. To differentiate between benign and malignant tumours respectively inflammatory bone diseases was not as a rule possible; however, the investigation yielded additional information completing the X-ray findings essentially. Thus very high storage of radioactivity was established for all osteosarcomas, whereas benign bone growths exhibited more circumscribed accumulations of activity. Skeletal scintiscanning for diagnostical purposes is particularly informative as to the early detection of bone foci evading X-ray diagnosis, more accurate delimitation of tumourous processes, and course control of tumours tending to degenerate. (orig./MG) [de

  19. Bone strength and material properties of the glenoid

    DEFF Research Database (Denmark)

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

    1997-01-01

    of bone specimens harvested from the central part of the glenoid subchondral area. The elastic modulus varied from approximately 100 MPa at the glenoid bare area to 400 MPa at the superior part of the glenoid. With the elastic constants used a predictor of the mechanical anisotropy, the average anisotropy...... ratio was 5.2, indicating strong anisotropy. The apparent density was an average 0.35 gr. cm-3, and the Poisson ratio averaged 0.263. According to our findings the anisotropy of the glenoid cancellous bone, details concerning the strength distribution, and the load-bearing function of the cortical shell......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...

  20. Preliminary result on trabecular bone score (TBS in lumbar vertebrae with experimentally altered microarchitecture

    Directory of Open Access Journals (Sweden)

    M. Di Stefano

    2013-01-01

    Full Text Available The aim of this preliminary research is to investigate the reliability of a new qualitative parameter, called Trabecular Bone Score (TBS, recently proposed for evaluating the microarchitectural arrangement of cancellous bone in scans carried out by dual energy X-ray absorptiometry (DXA. Vertebral bodies of 15 fresh samples of lumbar spines of adult pig were analysed either in basal conditions and with altered microarchitecture of the cancellous bone obtained by progressive drilling. The examined bony areas do not show changes in bone mineral density (BMD, whereas TBS values decrease with the increasing alteration of the vertebral microtrabecular structure. Our preliminary data seem to confirm the reliability of TBS as a qualitative parameter useful for evaluating the microarchitectural strength in bony areas quantitatively analysed by DXA.

  1. Biomimetic Materials and Fabrication Approaches for Bone Tissue Engineering.

    Science.gov (United States)

    Kim, Hwan D; Amirthalingam, Sivashanmugam; Kim, Seunghyun L; Lee, Seunghun S; Rangasamy, Jayakumar; Hwang, Nathaniel S

    2017-12-01

    Various strategies have been explored to overcome critically sized bone defects via bone tissue engineering approaches that incorporate biomimetic scaffolds. Biomimetic scaffolds may provide a novel platform for phenotypically stable tissue formation and stem cell differentiation. In recent years, osteoinductive and inorganic biomimetic scaffold materials have been optimized to offer an osteo-friendly microenvironment for the osteogenic commitment of stem cells. Furthermore, scaffold structures with a microarchitecture design similar to native bone tissue are necessary for successful bone tissue regeneration. For this reason, various methods for fabricating 3D porous structures have been developed. Innovative techniques, such as 3D printing methods, are currently being utilized for optimal host stem cell infiltration, vascularization, nutrient transfer, and stem cell differentiation. In this progress report, biomimetic materials and fabrication approaches that are currently being utilized for biomimetic scaffold design are reviewed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Alterations of bone microstructure and strength in end-stage renal failure.

    Science.gov (United States)

    Trombetti, A; Stoermann, C; Chevalley, T; Van Rietbergen, B; Herrmann, F R; Martin, P-Y; Rizzoli, R

    2013-05-01

    End-stage renal disease (ESRD) patients have a high risk of fractures. We evaluated bone microstructure and finite-element analysis-estimated strength and stiffness in patients with ESRD by high-resolution peripheral computed tomography. We observed an alteration of cortical and trabecular bone microstructure and of bone strength and stiffness in ESRD patients. Fragility fractures are common in ESRD patients on dialysis. Alterations of bone microstructure contribute to skeletal fragility, independently of areal bone mineral density. We compared microstructure and finite-element analysis estimates of strength and stiffness by high-resolution peripheral quantitative computed tomography (HR-pQCT) in 33 ESRD patients on dialysis (17 females and 16 males; mean age, 47.0 ± 12.6 years) and 33 age-matched healthy controls. Dialyzed women had lower radius and tibia cortical density with higher radius cortical porosity and lower tibia cortical thickness, compared to controls. Radius trabecular number was lower with higher heterogeneity of the trabecular network. Male patients displayed only a lower radius cortical density. Radius and tibia cortical thickness correlated negatively with bone-specific alkaline phosphatase (BALP). Microstructure did not correlate with parathyroid hormone (PTH) levels. Cortical porosity correlated positively with "Kidney Disease: Improving Global Outcomes" working group PTH level categories (r = 0.36, p microstructure and calculated bone strength are altered in ESRD patients, predominantly in women. Bone microstructure and biomechanical assessment by HR-pQCT may be of major clinical relevance in the evaluation of bone fragility in ESRD patients.

  3. Instrumental neutron activation analysis of rib bone samples and of bone reference materials

    International Nuclear Information System (INIS)

    Saiki, M.; Takata, M.K.; Kramarski, S.; Borelli, A.

    2000-01-01

    The instrumental neutron activation analysis method was used for the determination of trace elements in rib bone samples taken from autopsies of accident victims. The elements Br, Ca, Cl, Cr, Fe, Mg, Mn, Na, P, Sr, Rb and Zn were determined in cortical tissues by using short and long irradiations with thermal neutron flux of the IEA-R1m nuclear reactor. The reference materials NIST SRM 1400 Bone Ash and NIST SRM 1486 Bone Meal were also analyzed in order to evaluate the precision and the accuracy of the results. It was verified that lyophilization is the most convenient process for drying bone samples since it does not cause any element losses. Comparisons were made between the results obtained for rib samples and the literature values as well as between the results obtained for different ribs from a single individual and for bones from different individuals. (author)

  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

    and Interpore 500 HA/CC) were implanted into 5-mm bur holes in rabbit tibiae. There was no difference in the amount of newly formed bone around the four biomaterials. Interpore 500 HA/CC resorbed completely, whereas the other three biomaterials did not undergo any detectable biodegradation. Bio......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 500......-Oss was osseointegrated to a higher degree than the other biomaterials. Material characteristics obtained by diffuse reflectance infrared Fourier transform spectrometry analysis and energy-dispersive spectrometry did not explain the differences in biologic behavior....

  5. Alterations of the subchondral bone in osteochondral repair – translational data and clinical evidence

    Directory of Open Access Journals (Sweden)

    P Orth

    2013-06-01

    Full Text Available Alterations of the subchondral bone are pathological features associated with spontaneous osteochondral repair following an acute injury and with articular cartilage repair procedures. The aim of this review is to discuss their incidence, extent and relevance, focusing on recent knowledge gained from both translational models and clinical studies of articular cartilage repair. Efforts to unravel the complexity of subchondral bone alterations have identified (1 the upward migration of the subchondral bone plate, (2 the formation of intralesional osteophytes, (3 the appearance of subchondral bone cysts, and (4 the impairment of the osseous microarchitecture as potential problems. Their incidence and extent varies among the different small and large animal models of cartilage repair, operative principles, and over time. When placed in the context of recent clinical investigations, these deteriorations of the subchondral bone likely are an additional, previously underestimated, factor that influences the long-term outcome of cartilage repair strategies. Understanding the role of the subchondral bone in both experimental and clinical articular cartilage repair thus holds great promise of being translated into further improved cell- or biomaterial-based techniques to preserve and restore the entire osteochondral unit.

  6. Alterations of bone microstructure and strength in end-stage renal failure

    NARCIS (Netherlands)

    Trombetti, A.; Stoermann, C.; Chevalley, T.; Rietbergen, van B.; Hermann, F.R.; Martin, P.Y.; Rizzoli, R.

    2013-01-01

    Summary End-stage renal disease (ESRD) patients have a high risk of fractures. We evaluated bone microstructure and finite-element analysis-estimated strength and stiffness in patients with ESRD by high-resolution peripheral computed tomography. We observed an alteration of cortical and trabecular

  7. 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.

  8. Absence of bone sialoprotein (BSP) alters profoundly hematopoiesis and upregulates osteopontin.

    Science.gov (United States)

    Granito, Renata Neves; Bouleftour, Wafa; Sabido, Odile; Lescale, Chloé; Thomas, Mireille; Aubin, Jane E; Goodhardt, Michèle; Vico, Laurence; Malaval, Luc

    2015-06-01

    Matrix proteins of the SIBLING family interact with bone cells, extracellular matrix and mineral and are thus in a key position to regulate the microenvironment of the bone tissue, including its hematopoietic component. In this respect, osteopontin (OPN) has been implicated in the hematopoietic stem cell (HSC) niche as negative regulator of the HSC function. We investigated the impact on hematopoietic regulation of the absence of the cognate bone sialoprotein (BSP). BSP knockout (-/-) mice display increased bone marrow cellularity, and an altered commitment of hematopoietic precursors to myeloid lineages, leading in particular to an increased frequency of monocyte/macrophage cells. The B cell pool is increased in -/- bone marrow, and its composition is shifted toward more mature lymphocyte stages. BSP-null mice display a decreased HSC fraction among LSK cells and a higher percentage of more committed progenitors as compared to +/+. The fraction of proliferating LSK progenitors is higher in -/- mice, and after PTH treatment the mutant HSC pool is lower than in +/+. Strikingly, circulating levels of OPN as well as its expression in the bone tissue are much higher in the -/-. Thus, a BSP-null bone microenvironment affects the hematopoietic system both quantitatively and qualitatively, in a manner in part opposite to the OPN knockout, suggesting that the effects might in part reflect the higher OPN expression in the absence of BSP. © 2014 Wiley Periodicals, Inc.

  9. 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.

  10. Alendronate treatment alters bone tissues at multiple structural levels in healthy canine cortical bone.

    Science.gov (United States)

    Acevedo, Claire; Bale, Hrishikesh; Gludovatz, Bernd; Wat, Amy; Tang, Simon Y; Wang, Mingyue; Busse, Björn; Zimmermann, Elizabeth A; Schaible, Eric; Allen, Matthew R; Burr, David B; Ritchie, Robert O

    2015-12-01

    Bisphosphonates are widely used to treat osteoporosis, but have been associated with atypical femoral fractures (AFFs) in the long term, which raises a critical health problem for the aging population. Several clinical studies have suggested that the occurrence of AFFs may be related to the bisphosphonate-induced changes of bone turnover, but large discrepancies in the results of these studies indicate that the salient mechanisms responsible for any loss in fracture resistance are still unclear. Here the role of bisphosphonates is examined in terms of the potential deterioration in fracture resistance resulting from both intrinsic (plasticity) and extrinsic (shielding) toughening mechanisms, which operate over a wide range of length-scales. Specifically, we compare the mechanical properties of two groups of humeri from healthy beagles, one control group comprising eight females (oral doses of saline vehicle, 1 mL/kg/day, 3 years) and one treated group comprising nine females (oral doses of alendronate used to treat osteoporosis, 0.2mg/kg/day, 3 years). Our data demonstrate treatment-specific reorganization of bone tissue identified at multiple length-scales mainly through advanced synchrotron x-ray experiments. We confirm that bisphosphonate treatments can increase non-enzymatic collagen cross-linking at molecular scales, which critically restricts plasticity associated with fibrillar sliding, and hence intrinsic toughening, at nanoscales. We also observe changes in the intracortical architecture of treated bone at microscales, with partial filling of the Haversian canals and reduction of osteon number. We hypothesize that the reduced plasticity associated with BP treatments may induce an increase in microcrack accumulation and growth under cyclic daily loadings, and potentially increase the susceptibility of cortical bone to atypical (fatigue-like) fractures. Published by Elsevier Inc.

  11. Novel bone substitute material in alveolar bone healing following tooth extraction: an experimental study in sheep.

    Science.gov (United States)

    Liu, Jinyi; Schmidlin, Patrick R; Philipp, Alexander; Hild, Nora; Tawse-Smith, Andrew; Duncan, Warwick

    2016-07-01

    Electrospun cotton wool-like nanocomposite (ECWN) is a novel synthetic bone substitute that incorporates amorphous calcium phosphate nanoparticles into a biodegradable synthetic copolymer poly(lactide-co-glycolide). The objectives of this study were to develop a tooth extraction socket model in sheep for bone graft research and to compare ECWN and bovine-derived xenograft (BX) in this model. Sixteen cross-bred female sheep were used. Bilateral mandibular premolars were extracted atraumatically. Second and third premolar sockets were filled (Latin-square allocation) with BX, ECWN or left unfilled. Resorbable collagen membranes were placed over BX and selected ECWN grafted sockets. Eight sheep per time period were sacrificed after 8 and 16 weeks. Resin-embedded undemineralised sections were analysed for descriptive histology and histomorphometric analyses. At 8 weeks, there were with no distinct differences in healing among the different sites. At 16 weeks, osseous healing followed a fine trabecular pattern in ECWN sites. Non-grafted sites showed thick trabeculae separated by large areas of fibrovascular connective tissue. In BX grafted sites, xenograft particles were surrounded by newly formed bone or fibrovascular connective tissue. There were no statistically significant differences in bone formation across the four groups. However, ECWN sites had significantly less residual graft material than BX sites at 16 weeks (P = 0.048). This first description of a tooth extraction socket model in sheep supports the utility of this model for bone graft research. The results of this study suggested that the novel material ECWN did not impede bone ingrowth into sockets and showed evidence of material resorption. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. A novel hyperthermia treatment for bone metastases using magnetic materials

    International Nuclear Information System (INIS)

    Matsumine, Akihiko; Asanuma, Kunihiro; Matsubara, Takao; Nakamura, Tomoki; Uchida, Atsumasa; Sudo, Akihiro; Takegami, Kenji

    2011-01-01

    Patients with bone metastases in the extremities sometimes require surgical intervention to prevent deterioration of quality of life due to a pathological fracture. The use of localized radiotherapy combined with surgical reinforcement has been a gold standard for the treatment of bone metastases. However, radiotherapy sometimes induces soft tissue damage, including muscle induration and joint contracture. Moreover, cancer cells are not always radiosensitive. Hyperthermia has been studied since the 1940s using an experimental animal model to treat various types of advanced cancer, and studies have now reached the stage of clinical application, especially in conjunction with radiotherapy or chemotherapy. Nevertheless, bone metastases have several special properties which discourage oncologists from developing hyperthermic therapeutic strategies. First, the bone is located deep in the body, and has low thermal conductivity due to the thickness of cortical bone and the highly vascularized medulla. To address these issues, we developed new hyperthermic strategies which generate heat using magnetic materials under an alternating electromagnetic field, and started clinical application of this treatment modality. The purpose of this review is to summarize the latest studies on hyperthermic treatment in the field of musculoskeletal tumors, and to introduce the treatment strategy employing our novel hyperthermia approach. (author)

  13. A comparative analysis of microscopic alterations in modern and ancient undecalcified and decalcified dry bones.

    Science.gov (United States)

    Caruso, Valentina; Cummaudo, Marco; Maderna, Emanuela; Cappella, Annalisa; Caudullo, Giorgio; Scarpulla, Valentina; Cattaneo, Cristina

    2018-02-01

    The present study aims to evaluate the preservation of the microstructure of skeletal remains collected from four different known burial sites (archaeological and contemporary). Histological analysis on undecalcified and decalcified thin sections was performed in order to assess which of the two techniques is more affected by taphonomic insults. A histological analysis was performed on both undecalcified and decalcified thin sections of 40 long bones and the degree of diagenetic change was evaluated using transmitted and polarized light microscopy according to the Oxford Histological Index (OHI). In order to test the optical behavior of bone tissue, thin sections were observed by polarized light microscopy and the intensity of birefringence was evaluated. The more ancient samples are generally characterized by a low OHI (0-1) with extensive microscopic focal destruction; recent samples exhibited a better preservation of bone micromorphology. When comparing undecalcified to decalcified thin sections, the latter showed an amelioration in the conservation of microscopic structure. As regards the birefringence, it was very low in all the undecalcified thin sections, whereas decalcification process seems to improve its visibility. The preservation of the bone microscopic structure appears to be influenced not only by age, but also by the burial context. Undecalcified bones appear to be more affected by taphonomical alterations, probably because of the thickness of the thin sections; on the contrary, decalcified thin sections proved to be able to tackle this issue allowing a better reading of the bone tissue. © 2017 Wiley Periodicals, Inc.

  14. A novel algorithm for a precise analysis of subchondral bone alterations

    Science.gov (United States)

    Gao, Liang; Orth, Patrick; Goebel, Lars K. H.; Cucchiarini, Magali; Madry, Henning

    2016-01-01

    Subchondral bone alterations are emerging as considerable clinical problems associated with articular cartilage repair. Their analysis exposes a pattern of variable changes, including intra-lesional osteophytes, residual microfracture holes, peri-hole bone resorption, and subchondral bone cysts. A precise distinction between them is becoming increasingly important. Here, we present a tailored algorithm based on continuous data to analyse subchondral bone changes using micro-CT images, allowing for a clear definition of each entity. We evaluated this algorithm using data sets originating from two large animal models of osteochondral repair. Intra-lesional osteophytes were detected in 3 of 10 defects in the minipig and in 4 of 5 defects in the sheep model. Peri-hole bone resorption was found in 22 of 30 microfracture holes in the minipig and in 17 of 30 microfracture holes in the sheep model. Subchondral bone cysts appeared in 1 microfracture hole in the minipig and in 5 microfracture holes in the sheep model (n = 30 holes each). Calculation of inter-rater agreement (90% agreement) and Cohen’s kappa (kappa = 0.874) revealed that the novel algorithm is highly reliable, reproducible, and valid. Comparison analysis with the best existing semi-quantitative evaluation method was also performed, supporting the enhanced precision of this algorithm. PMID:27596562

  15. 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.

  16. Alterations in proteins of bone marrow extracellular matrix in undernourished mice

    Directory of Open Access Journals (Sweden)

    C.L. Vituri

    2000-08-01

    Full Text Available The objective of the present study was to determine the effect of protein malnutrition on the glycoprotein content of bone marrow extracellular matrix (ECM. Two-month-old male Swiss mice were submitted to protein malnutrition with a low-protein diet containing 4% casein as compared to 20% casein in the control diet. When the experimental group had attained a 20% loss of their original body weight, we extracted the ECM proteins from bone marrow with PBS buffer, and analyzed ECM samples by SDS-PAGE (7.5% and ECL Western blotting. Quantitative differences were observed between control and experimental groups. Bone marrow ECM from undernourished mice had greater amounts of extractable fibronectin (1.6-fold increase and laminin (4.8-fold increase when compared to the control group. These results suggest an association between fluctuations in the composition of the hematopoietic microenvironment and altered hematopoiesis observed in undernourished mice.

  17. 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

  18. Knee joint pain potentially due to bone alterations in a knee osteoarthritis patient.

    Science.gov (United States)

    Komatsu, Masatoshi; Nakamura, Yukio; Kamimura, Mikio; Uchiyama, Shigeharu; Mukaiyama, Keijiro; Ikegami, Shota; Kato, Hiroyuki

    2014-12-01

    Osteoarthritis (OA) is the leading cause of musculoskeletal pain and functional disability worldwide. However, the etiology of this condition is still largely unknown. We report the clinical course of an elderly man with knee OA. Plain radiographs and MRI examinations performed during follow-up suggested that the pathophysiology of the patient's knee OA and joint pain may have been primarily due to bone alterations.

  19. 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.

  20. Alteration in Bone Mineral Metabolism in Children with Acute Lymphoblastic Leukemia (ALL: A Review

    Directory of Open Access Journals (Sweden)

    Chowdhury Yakub Jamal

    2009-11-01

    Full Text Available In recent years there has been a significant increase in event free survival (EFS and overall survival in children with cancer. As survival rates for childhood cancer have radically improved, late effects associated with the successful but highly intensive chemotherapy and/or radiotherapy have dramatically increased. Many possible late effects of cancer treatment are recognized in pediatric cancer patients as infertility, endocrine deficiency, renal failure, pulmonary and cardiac toxicity, obesity and osteopenia/osteoporosis. Decreased bone mineral density (BMD and bone metabolism disturbances have been recognized and reported in literature. Osteopenia/osteoporosis skeletal abnormalities, osteonecrosis and pathological fractures are known to occur frequently in childhood acute lymphoblastic leukemia (ALL at diagnosis, during and after treatment with chemotherapy. Various studies have revealed different metabolic alterations related to ALL. Some suggestions have been made about their relationship with the disease process. Various metabolic abnormalities may be encountered in the newly diagnosed ALL patients. It includes decreased and increased serum levels of calcium and phosphate. Hypercalcemia may result from leukemic infiltrations of bone and release of parathormone like substance from lymphoblast. Elevated serum phosphate can occur as a result of leukemic cell lysis and may induce hypocalcemia. It has been postulated by other authors that leukemic cells may directly infiltrate bone and produce parathroid hormone related peptides, prostaglandin E and osteoblast inhibiting factors. Hypomagnesemia, hypocalcaemia and hypothyroidisum have been demonstrated in patients with ALL. Some patients may have poor nutrition and decreased physical activities during treatment. However postulations have also been made that chemotherapy may play a role in creating metabolic alterations in children with ALL. Corticosteroid, methotraxate and cranial irradiations

  1. Label-free Raman spectroscopy provides early determination and precise localization of breast cancer-colonized bone alterations.

    Science.gov (United States)

    Zhang, Chi; Winnard, Paul T; Dasari, Sidarth; Kominsky, Scott L; Doucet, Michele; Jayaraman, Swaathi; Raman, Venu; Barman, Ishan

    2018-01-21

    Breast neoplasms frequently colonize bone and induce development of osteolytic bone lesions by disrupting the homeostasis of the bone microenvironment. This degenerative process can lead to bone pain and pathological bone fracture, a major cause of cancer morbidity and diminished quality of life, which is exacerbated by our limited ability to monitor early metastatic disease in bone and assess fracture risk. Spurred by its label-free, real-time nature and its exquisite molecular specificity, we employed spontaneous Raman spectroscopy to assess and quantify early metastasis driven biochemical alterations to bone composition. As early as two weeks after intracardiac inoculations of MDA-MB-435 breast cancer cells in NOD-SCID mice, Raman spectroscopic measurements in the femur and spine revealed consistent changes in carbonate substitution, overall mineralization as well as crystallinity increase in tumor-bearing bones when compared with their normal counterparts. Our observations reveal the possibility of early stage detection of biochemical changes in the tumor-bearing bones - significantly before morphological variations are captured through radiographic diagnosis. This study paves the way for a better molecular understanding of altered bone remodeling in such metastatic niches, and for further clinical studies with the goal of establishing a non-invasive tool for early metastasis detection and prediction of pathological fracture risk in breast cancer.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    from the iliac crest. For both groups, mononuclear cells were isolated, and injected into a perfusion bioreactor (Millenium Biologix AG, Switzerland). Scaffold granules (Ø~900-1500 µm, ~88% porosity) in group 1, consisted of hydroxyapatite (HA, 70%) with β-tricalcium-phosphate (β-TCP, 30%) (Danish....... The superficial part was used for mechanical testing and micro-CT scanning, and the profound part for histomorphometry. Push-out tests were performed on an 858 Bionix MTS hydraulic materials testing machine (MTS Systems Corporation, USA). Shear mechanical properties between implant and newly generated bone were...

  3. Hard tissue regeneration using bone substitutes: an update on innovations in materials.

    Science.gov (United States)

    Sarkar, Swapan Kumar; Lee, Byong Taek

    2015-05-01

    Bone is a unique organ composed of mineralized hard tissue, unlike any other body part. The unique manner in which bone can constantly undergo self-remodeling has created interesting clinical approaches to the healing of damaged bone. Healing of large bone defects is achieved using implant materials that gradually integrate with the body after healing is completed. Such strategies require a multidisciplinary approach by material scientists, biological scientists, and clinicians. Development of materials for bone healing and exploration of the interactions thereof with the body are active research areas. In this review, we explore ongoing developments in the creation of materials for regenerating hard tissues.

  4. 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.)

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

    International Nuclear Information System (INIS)

    Reix, Philippe; Bellon, Gabriel; Braillon, Pierre

    2010-01-01

    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.)

  6. The in vitro viability and growth of fibroblasts cultured in the presence of different bone grafting materials (NanoBone and Straumann Bone Ceramic).

    Science.gov (United States)

    Kauschke, E; Rumpel, E; Fanghänel, J; Bayerlein, T; Gedrange, T; Proff, P

    2006-02-01

    Different clinical applications, including dentistry, are making increasing demands on bone grafting material. In the present study we have analysed the viability, proliferation and growth characteristics of fibroblasts cultured in vitro together with two different bone grafting materials, NanoBone and Straumann Bone Ceramic, over a period of 24 and 28 days respectively. Viability was measured at least every 72 hours by using the alamarBlue assay, a test that measures quantitatively cell proliferation and viability but does not require cell fixation or extraction. After one week of culture fibroblast viability was as high as in controls for both grafting materials and remained high (> 90%) for the duration of the experiment. Cell growth was evaluated microscopically. Scanning electron microscopy revealed a dense fibroblast growth at the surface of both bone grafting materials after three weeks of in vitro culture. Generally, our in vitro analyses contribute to further insights into cell - scaffold interactions.

  7. 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.

  8. Corrosion and alteration of materials from the nuclear industry

    International Nuclear Information System (INIS)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Feron, D.; Guerin, Y.; Latge, C.; Limoge, Y.; Madic, C.; Santarini, G.; Seiler, J.M.; Vernaz, E.; Richet, C.

    2010-01-01

    , testing means, experimental techniques, internal corrosion of zircaloy sheath - the iodine effect, stress corrosion of nickel alloys - hydrogen influence, stress corrosion of stainless steels; C - wear corrosion: a coupled phenomenon, research in the framework of service life extension of the French electronuclear park; 3 - Corrosion in future reactors: A - corrosion in gas reactors: corrosion by helium impurities, oxidation resistance of silicon carbide, corrosion of graphite and carbon-carbon composites; B - corrosion in liquid metal reactors: sodium FBRs, lead and lead alloys reactors; C- corrosion in molten salt reactors: corrosion of Hastelloy N-type nickel alloys by molten fluorides, mass transfer in aniso-thermal fluoride systems, tellurium embrittlement, electrochemical study of pure metals corrosion in molten fluorides; 4 - Materials corrosion and alteration in the back-end of the fuel cycle: A - corrosion in concentrated nitric environment: materials behaviour, self-catalytic mechanism of nitric acid reduction; B - corrosion in unsaturated aqueous environment: metallic corrosion in unsaturated environment - application to the storage of waste containers, bitumens alteration, reinforced concrete behaviour and iron framework corrosion, concrete behaviour in severe thermal environment; C - Corrosion in saturated aqueous environment: metals corrosion in clayey environment, long-term behaviour of glasses, ceramics alteration, underwater concrete durability, clays transformation; D - materials biodegradation: microorganisms and nuclear wastes, biodegradation of bitumen, concretes and steels; 5 - Conclusion, glossary

  9. Behavior of bone cells in contact with magnesium implant material.

    Science.gov (United States)

    Burmester, Anna; Willumeit-Römer, Regine; Feyerabend, Frank

    2017-01-01

    Magnesium-based implants exhibit several advantages, such as biodegradability and possible osteoinductive properties. Whether the degradation may induce cell type-specific changes in metabolism still remains unclear. To examine the osteoinductivity mechanisms, the reaction of bone-derived cells (MG63, U2OS, SaoS2, and primary human osteoblasts (OB)) to magnesium (Mg) was determined. Mg-based extracts were used to mimic more realistic Mg degradation conditions. Moreover, the influence of cells having direct contact with the degrading Mg metal was investigated. In exposure to extracts and in direct contact, the cells decreased pH and osmolality due to metabolic activity. Proliferating cells showed no significant reaction to extracts, whereas differentiating cells were negatively influenced. In contrast to extract exposure, where cell size increased, in direct contact to magnesium, cell size was stable or even decreased. The amount of focal adhesions decreased over time on all materials. Genes involved in bone formation were significantly upregulated, especially for primary human osteoblasts. Some osteoinductive indicators were observed for OB: (i) an increased cell count after extract addition indicated a higher proliferation potential; (ii) increased cell sizes after extract supplementation in combination with augmented adhesion behavior of these cells suggest an early switch to differentiation; and (iii) bone-inducing gene expression patterns were determined for all analyzed conditions. The results from the cell lines were inhomogeneous and showed no specific stimulus of Mg. The comparison of the different cell types showed that primary cells of the investigated tissue should be used as an in vitro model if Mg is analyzed. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 165-179, 2017. © 2015 Wiley Periodicals, Inc.

  10. [Children, Collect Bones! : Teaching Aids and Propaganda Material on Bone-Collections and Bone-Utilisation Used in German Schools During the "Third Reich"].

    Science.gov (United States)

    Vaupel, Elisabeth; Preiß, Florian

    2018-06-05

    In the nineteenth and early twentieth centuries bones were an essential raw material for the German chemical industry, vital to the production of fertilizer, glue, gelatine, soap and other products. As most of this material was imported, the German school system during the "Third Reich" took the utilisation of bones as an example to illustrate the relevance of the four-year plan of 1936 and its policy of economic self-sufficiency. The school children were encouraged to collect bones from domestic sources and bring them to the collecting points in the schools. Several NS-institutions developed a variety of teaching aids and materials to support school education on this economically and politically important topic. Focussing on the example of bone-utilisation, this paper examines the messages and intentions of these educational materials. It also demonstrates how even apparently ideologically unbiased school subjects, such as chemistry, were instrumentalised for the political indoctrination of the pupils.

  11. Mechanism of Action of Bortezomib and the New Proteasome Inhibitors on Myeloma Cells and the Bone Microenvironment: Impact on Myeloma-Induced Alterations of Bone Remodeling

    Directory of Open Access Journals (Sweden)

    Fabrizio Accardi

    2015-01-01

    Full Text Available Multiple myeloma (MM is characterized by a high capacity to induce alterations in the bone remodeling process. The increase in osteoclastogenesis and the suppression of osteoblast formation are both involved in the pathophysiology of the bone lesions in MM. The proteasome inhibitor (PI bortezomib is the first drug designed and approved for the treatment of MM patients by targeting the proteasome. However, recently novel PIs have been developed to overcome bortezomib resistance. Interestingly, several preclinical data indicate that the proteasome complex is involved in both osteoclast and osteoblast formation. It is also evident that bortezomib either inhibits osteoclast differentiation induced by the receptor activator of nuclear factor kappa B (NF-κB ligand (RANKL or stimulates the osteoblast differentiation. Similarly, the new PIs including carfilzomib and ixazomib can inhibit bone resorption and stimulate the osteoblast differentiation. In a clinical setting, PIs restore the abnormal bone remodeling by normalizing the levels of bone turnover markers. In addition, a bone anabolic effect was described in responding MM patients treated with PIs, as demonstrated by the increase in the osteoblast number. This review summarizes the preclinical and clinical evidence on the effects of bortezomib and other new PIs on myeloma bone disease.

  12. Evaluation of bone alterations in the jaws of HIV-infected menopausal women

    Directory of Open Access Journals (Sweden)

    Bruno Vieira Caputo

    2013-06-01

    Full Text Available The advent of highly active antiretroviral therapy (HAART has caused a reduction in mortality, thus contributing to an increase in the number of women with HIVࢧAIDS who reach the climacteric period, experience decline in ovarian function, and develop complications of viral infection and HAART, which can accelerate bone loss. The aim of this study was to detect possible alterations in the jaws of HIV-infected women by panoramic radiography. The study comprised a total of 120 women above 40 years of age who were divided into the following two groups: women who are HIV positive (Group I and women with no known HIV infection (Group II. Measurement of the following three radiomorphometric indexes was performed by panoramic radiography: Mental Index (MI, Panoramic Mandibular Index (PMI and Antegonial Depth (AD. A total of 70% of women in the control group and 50% of women in the HIV group were in the postmenopausal period, and the average values of both MI (p = 0.0054 and AD (p < 0.0001 for this period were lower in the HIV group than in the control group. For patients who were in the premenopausal period, the average AD was lower in the HIV group than in the control group (p = 0.0003. Despite the difference in the average age between groups, greater bone resorption in the mandible was found in the group of HIV-positive women.

  13. Developmental Toxicity Studies with Pregabalin in Rats: Significance of Alterations in Skull Bone Morphology.

    Science.gov (United States)

    Morse, Dennis C; Henck, Judith W; Bailey, Steven A

    2016-04-01

    Pregabalin was administered to pregnant Wistar rats during organogenesis to evaluate potential developmental toxicity. In an embryo-fetal development study, compared with controls, fetuses from pregabalin-treated rats exhibited increased incidence of jugal fused to maxilla (pregabalin 1250 and 2500 mg/kg) and fusion of the nasal sutures (pregabalin 2500 mg/kg). The alterations in skull development occurred in the presence of maternal toxicity (reduced body weight gain) and developmental toxicity (reduced fetal body weight and increased skeletal variations), and were initially classified as malformations. Subsequent investigative studies in pregnant rats treated with pregabalin during organogenesis confirmed the advanced jugal fused to maxilla, and fusion of the nasal sutures at cesarean section (gestation day/postmating day [PMD] 21) in pregabalin-treated groups. In a study designed to evaluate progression of skull development, advanced jugal fused to maxilla and fusion of the nasal sutures was observed on PMD 20-25 and PMD 21-23, respectively (birth occurs approximately on PMD 22). On postnatal day (PND) 21, complete jugal fused to maxilla was observed in the majority of control and 2500 mg/kg offspring. No treatment-related differences in the incidence of skull bone fusions occurred on PND 21, indicating no permanent adverse outcome. Based on the results of the investigative studies, and a review of historical data and scientific literature, the advanced skull bone fusions were reclassified as anatomic variations. Pregabalin was not teratogenic in rats under the conditions of these studies. © 2016 Wiley Periodicals, Inc.

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

    International Nuclear Information System (INIS)

    Chen, Zonggang; Kang, Lingzhi; Meng, Qing-Yuan; Liu, Huanye; Wang, Zhaoliang; Guo, Zhongwu; Cui, Fu-Zhai

    2014-01-01

    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

  15. 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.

  16. Early life vitamin D depletion alters the postnatal response to skeletal loading in growing and mature bone

    Science.gov (United States)

    Buckley, Harriet; Owen, Robert; Marin, Ana Campos; Lu, Yongtau; Eyles, Darryl; Lacroix, Damien; Reilly, Gwendolen C.; Skerry, Tim M.; Bishop, Nick J.

    2018-01-01

    There is increasing evidence of persistent effects of early life vitamin D exposure on later skeletal health; linking low levels in early life to smaller bone size in childhood as well as increased fracture risk later in adulthood, independently of later vitamin D status. A major determinant of bone mass acquisition across all ages is mechanical loading. We tested the hypothesis in an animal model system that early life vitamin D depletion results in abrogation of the response to mechanical loading, with consequent reduction in bone size, mass and strength during both childhood and adulthood. A murine model was created in which pregnant dams were either vitamin D deficient or replete, and their offspring moved to a vitamin D replete diet at weaning. Tibias of the offspring were mechanically loaded and bone structure, extrinsic strength and growth measured both during growth and after skeletal maturity. Offspring of vitamin D deplete mice demonstrated lower bone mass in the non loaded limb and reduced bone mass accrual in response to loading in both the growing skeleton and after skeletal maturity. Early life vitamin D depletion led to reduced bone strength and altered bone biomechanical properties. These findings suggest early life vitamin D status may, in part, determine the propensity to osteoporosis and fracture that blights later life in many individuals. PMID:29370213

  17. Perinatal exposure to PCB 153, but not PCB 126, alters bone tissue composition in female goat offspring

    International Nuclear Information System (INIS)

    Lundberg, Rebecca; Lyche, Jan L.; Ropstad, Erik; Aleksandersen, Mona; Roenn, Monika; Skaare, Janneche U.; Larsson, Sune; Orberg, Jan; Lind, P. Monica

    2006-01-01

    The aim of this study was to investigate if environmentally relevant doses of the putative estrogenic non dioxin-like PCB 153 and the dioxin-like PCB 126 caused changes in bone tissue in female goat offspring following perinatal exposure. Goat dams were orally dosed with PCB 153 in corn oil (98 μg/kg body wt/day) or PCB 126 (49 ng/kg body wt/day) from day 60 of gestation until delivery. The offspring were exposed to PCB in utero and through mother's milk. The suckling period lasted for 6 weeks. Offspring metacarpal bones were analysed using peripheral quantitative computed tomography (pQCT) after euthanisation at 9 months of age. The diaphyseal bone was analysed at a distance of 18% and 50% of the total bone length, and the metaphyseal bone at a distance of 9%. Also, biomechanical three-point bending of the bones was conducted, with the load being applied to the mid-diaphyseal pQCT measure point (50%). PCB 153 exposure significantly decreased the total cross-sectional area (125 mm 2 ± 4) versus non-exposed (142 mm 2 ± 5), decreased the marrow cavity (38 mm 2 ± 4) versus non-exposed (50 mm 2 ± 3) and decreased the moment of resistance (318 mm 3 ± 10) versus non-exposed (371 mm 3 ± 20) at the diaphyseal 18% measure point. At the metaphyseal measure point, the trabecular bone mineral density (121 mg/cm 3 ± 5) was increased versus non-exposed (111 mg/cm 3 ± 3). PCB 126 exposure did not produce any observable changes in bone tissue. The biomechanical testing of the bones did not show any significant changes in bone strength after PCB 153 or PCB 126 exposure. In conclusion, perinatal exposure to PCB 153, but not PCB 126, resulted in altered bone composition in female goat offspring

  18. Synthetic bone substitute material comparable with xenogeneic material for bone tissue regeneration in oral cancer patients: First and preliminary histological, histomorphometrical and clinical results.

    Science.gov (United States)

    Ghanaati, Shahram; Barbeck, Mike; Lorenz, Jonas; Stuebinger, Stefan; Seitz, Oliver; Landes, Constantin; Kovács, Adorján F; Kirkpatrick, Charles J; Sader, Robert A

    2013-07-01

    The present study was first to evaluate the material-specific cellular tissue response of patients with head and neck cancer to a nanocrystalline hydroxyapatite bone substitute NanoBone (NB) in comparison with a deproteinized bovine bone matrix Bio-Oss (BO) after implantation into the sinus cavity. Eight patients with tumor resection for oral cancer and severely resorbed maxillary bone received materials according to a split mouth design for 6 months. Bone cores were harvested prior to implantation and analyzed histologically and histomorphometrically. Implant survival was followed-up to 2 years after placement. Histologically, NB underwent a higher vascularization and induced significantly more tartrate-resistant acid phosphatase-positive (TRAP-positive) multinucleated giant cells when compared with BO, which induced mainly mononuclear cells. No significant difference was observed in the extent of new bone formation between both groups. The clinical follow-up showed undisturbed healing of all implants in the BO-group, whereas the loss of one implant was observed in the NB-group. Within its limits, the present study showed for the first time that both material classes evaluated, despite their induction of different cellular tissue reactions, may be useful as augmentation materials for dental and maxillofacial surgical applications, particularly in patients who previously had oral cancer.

  19. 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...... 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...

  20. 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.

  1. 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.

  2. 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

  3. Beneficial effects of a N-terminally modified GIP agonist on tissue-level bone material properties.

    Science.gov (United States)

    Mabilleau, Guillaume; Mieczkowska, Aleksandra; Irwin, Nigel; Simon, Yannick; Audran, Maurice; Flatt, Peter R; Chappard, Daniel

    2014-06-01

    Bone remodeling is under complex regulation from nervous, hormonal and local signals, including gut hormones. Among the gut hormones, a role for the glucose-dependent insulinotropic polypeptide (GIP) has been suggested. However, the rapid degradation of GIP in the bloodstream by the ubiquitous enzyme dipeptidyl peptidase-4 (DPP-4) precludes therapeutic use. To circumvent this problem, a series of N-terminally modified GIP agonists have been developed, with N-AcGIP being the most promising. The aims of the present study were to investigate the effects of N-AcGIP on bone at the micro-level using trabecular and cortical microstructural morphology, and at the tissue-level in rats. Copenhagen rats were randomly assigned into control or N-AcGIP-treated groups and received daily injection for 4 weeks. Bone microstructural morphology was assessed by microCT and dynamic histomorphometry and tissue-level properties by nanoindentation, qBEI and infra-red microscopy. Four week treatment with N-AcGIP did not alter trabecular or cortical microstructural morphology. In addition, no significant modifications of mechanical response and properties at the tissue-level were observed in trabecular bone. However, significant augmentations in maximum load (12%), hardness (14%), indentation modulus (13%) and dissipated energy (16%) were demonstrated in cortical bone. These beneficial modifications of mechanical properties at the tissue-level were associated with increased mineralization (22%) and collagen maturity (13%) of the bone matrix. Taken together, the results support a beneficial role of GIP, and particularly stable analogs such as N-AcGIP, on tissue material properties of bone. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. The effect of patient age on bone formation using a fully synthetic nanocrystalline bone augmentation material in maxillary sinus grafting.

    Science.gov (United States)

    Wolf, Michael; Wurm, Alexander; Heinemann, Friedhelm; Gerber, Thomas; Reichert, Christoph; Jäger, Andreas; Götz, Werner

    2014-01-01

    Maxillary sinus floor augmentation is a treatment that has been proposed for patients in whom the alveolar bone height is insufficient. This procedure is commonly used in patients aged 40 to 70 years and older. However, little information exists whether the factor of age might influence the outcome of augmentation procedures. The aim of this study was to investigate whether the patient's age has an effect on bone formation and incorporation in maxillary sinus floor augmentation procedures. A fully synthetic nanocrystalline bone augmentation material (NanoBone, Artoss) was used for sinus floor augmentation in patients with a subantral vertical bone height of at least 3 mm and maximum of 7 mm. After 7 months healing time, biopsy specimens were taken and were divided into two groups according to the patient's age. Exclusion criteria were poor general health (eg, severe renal/and or liver disease), history of a radiotherapy in the head region, chemotherapy at the time of surgical procedure, noncompensated diabetes mellitus, symptoms of a maxillary sinus disease, active periodontal or systemic diseases, smoking, and poor oral hygiene. Histologic analyses with hematoxylin-eosin stain were performed. Multinucleated osteoclast-like cells were identified by histochemical staining (tartrate-resistant acid phosphatase [TRAP]). Quantitative and age-dependent assessment of bone formation, residual bone grafting material, and soft tissue formation following sinus augmentation was performed using histomorphometric analysis and the Bonferroni adjustment of the Student t test. Twenty biopsy specimens from 17 patients were taken and divided into two groups according to age (group 1: 41 to 52 years; group 2: 66 to 71 years) containing 10 specimens each, which were analyzed in triplicate resulting in a total of 30 specimens per group. A regeneration process with varying amounts of newly formed bone surrounded by marrow-like tissue was present in all augmented regions. No signs of

  5. 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...

  6. Bone turnover is altered in transgenic rats overexpressing the P2Y2 purinergic receptor

    DEFF Research Database (Denmark)

    Ellegaard, Maria; Agca, Cansu; Petersen, Solveig

    2017-01-01

    overexpression on bone status and bone cell function using a transgenic rat. Three-month-old female transgenic Sprague Dawley rats overexpressing P2Y2R (P2Y2R-Tg) showed higher bone strength of the femoral neck. Histomorphometry showed increase in resorptive surfaces and reduction in mineralizing surfaces. Both...

  7. Overexpression of BMP3 in the developing skeleton alters endochondral bone formation resulting in spontaneous rib fractures.

    Science.gov (United States)

    Gamer, Laura W; Cox, Karen; Carlo, Joelle M; Rosen, Vicki

    2009-09-01

    Bone morphogenetic protein-3 (BMP) has been identified as a negative regulator in the skeleton as mice lacking BMP3 have increased bone mass. To further understand how BMP3 mediates bone formation, we created transgenic mice overexpressing BMP3 using the type I collagen promoter. BMP3 transgenic mice displayed spontaneous rib fractures that were first detected at E17.0. The fractures were due to defects in differentiation of the periosteum and late hypertrophic chondrocytes resulting in thinner cortical bone with decreased mineralization. As BMP3 modulates BMP and activin signaling through ActRIIB, we examined the ribs of ActRIIB receptor knockout mice and found they had defects in late chondrogenesis and mineralization similar to BMP3 transgenic mice. These data suggest that BMP3 exerts its effects in the skeleton by altering signaling through ActRIIB in chondrocytes and the periosteum, and this results in defects in bone collar formation and late hypertrophic chondrocyte maturation leading to decreased mineralization and less bone. 2009 Wiley-Liss, Inc.

  8. Multi-material 3D Models for Temporal Bone Surgical Simulation.

    Science.gov (United States)

    Rose, Austin S; Kimbell, Julia S; Webster, Caroline E; Harrysson, Ola L A; Formeister, Eric J; Buchman, Craig A

    2015-07-01

    A simulated, multicolor, multi-material temporal bone model can be created using 3-dimensional (3D) printing that will prove both safe and beneficial in training for actual temporal bone surgical cases. As the process of additive manufacturing, or 3D printing, has become more practical and affordable, a number of applications for the technology in the field of Otolaryngology-Head and Neck Surgery have been considered. One area of promise is temporal bone surgical simulation. Three-dimensional representations of human temporal bones were created from temporal bone computed tomography (CT) scans using biomedical image processing software. Multi-material models were then printed and dissected in a temporal bone laboratory by attending and resident otolaryngologists. A 5-point Likert scale was used to grade the models for their anatomical accuracy and suitability as a simulation of cadaveric and operative temporal bone drilling. The models produced for this study demonstrate significant anatomic detail and a likeness to human cadaver specimens for drilling and dissection. Simulated temporal bones created by this process have potential benefit in surgical training, preoperative simulation for challenging otologic cases, and the standardized testing of temporal bone surgical skills. © The Author(s) 2015.

  9. Alteration of the cementitious material under the saline environment

    International Nuclear Information System (INIS)

    Owada, H.; Asano, H.; Kuno, Y.; Sakamoto, H.; Shimoda, S.

    2006-01-01

    Leaching experiment of ordinary and fly ash mixed cement were carried out by using the artificial sea water and deionized water as leachates. The pH values of saline leachates were decreased at the lower solid/liquid ratio in comparison with the case of deionized leachates. Mg(OH) 2 and ettringite were observed only in the case of saline water. The results of the geochemical calculation with inputs of Mg(OH) 2 , ettringite and hydrotalcite well represented in the change of pH value and the mineral-composition with those of the experiment. However, in the latter stage of the fly ash mixed cement case, calculated concentrations of Si and Al of the leachate weren't consistent with the observed values. These results showed that substitution of Mg for Ca and influences of sulfate ion should be considered in the modeling of the cement alteration in the saline water case, and Al-substituted C-S-H might be considered in the alteration of fly ash mixed cement. (author)

  10. Severely impaired bone material quality in Chihuahua zebrafish resembles classical dominant human osteogenesis imperfecta.

    Science.gov (United States)

    Fiedler, Imke A K; Schmidt, Felix N; Wölfel, Eva M; Plumeyer, Christine; Milovanovic, Petar; Gioia, Roberta; Tonelli, Francesca; Bale, Hrishikesh A; Jähn, Katharina; Besio, Roberta; Forlino, Antonella; Busse, Björn

    2018-04-17

    Excessive skeletal deformations and brittle fractures in the vast majority of patients suffering from osteogenesis imperfecta (OI) are a result of substantially reduced bone quality. Since the mechanical competence of bone is dependent on the tissue characteristics at small length scales, it is of crucial importance to assess how osteogenesis imperfecta manifests at the micro- and nanoscale of bone. In this context, the Chihuahua (Chi/ +) zebrafish, carrying a heterozygous glycine substitution in the α1 chain of collagen type I, has recently been proposed as suitable animal model of classical dominant OI, showing skeletal deformities, altered mineralization patterns and a smaller body size. This study assessed the bone quality properties of Chi/+ at multiple length scales using micro-computed tomography (micro-CT), histomorphometry, quantitative back-scattered electron imaging, Fourier transform infrared spectroscopy, nanoindentation and X-ray microscopy. At the skeletal level, Chi/+ display smaller body size, deformities and fracture calli in the ribs. Morphological changes at the whole bone level showed that the vertebrae in Chi/+ had a smaller size, smaller thickness and distorted shape. At the tissue level, Chi/+ displayed a higher degree of mineralization, lower collagen maturity, lower mineral maturity, altered osteoblast morphology, and lower osteocyte lacunar density compared to WT. The alterations in the cellular, compositional and structural properties of Chi/+ bones bear an explanation for the impaired local mechanical properties, which promote an increase in overall bone fragility in Chi/ +. The quantitative assessment of bone quality in Chi/+ thus further validates this mutant as an important model reflecting osseous characteristics associated with human classical dominant osteogenesis imperfecta. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  11. Porous Polyethylene Coated with Functionalized Hydroxyapatite Particles as a Bone Reconstruction Material

    Directory of Open Access Journals (Sweden)

    H. Fouad

    2018-03-01

    Full Text Available In this study, porous polyethylene scaffolds were examined as bone substitutes in vitro and in vivo in critical-sized calvarial bone defects in transgenic Sprague-Dawley rats. A microscopic examination revealed that the pores appeared to be interconnected across the material, making them suitable for cell growth. The creep recovery behavior of porous polyethylene at different loads indicated that the creep strain had two main portions. In both portions, strain increased with increased applied load and temperature. In terms of the thermographic behavior of the material, remarkable changes in melting temperature and heat fusion were revealed with increased the heating rates. The tensile strength results showed that the material was sensitive to the strain rate and that there was adequate mechanical strength to support cell growth. The in vitro cell culture results showed that human bone marrow mesenchymal stem cells attached to the porous polyethylene scaffold. Calcium sulfate–hydroxyapatite (CS–HA coating of the scaffold not only improved attachment but also increased the proliferation of human bone marrow mesenchymal stem cells. In vivo, histological analysis showed that the study groups had active bone remodeling at the border of the defect. Bone regeneration at the border was also evident, which confirmed that the polyethylene acted as an osteoconductive bone graft. Furthermore, bone formation inside the pores of the coated polyethylene was also noted, which would enhance the process of osteointegration.

  12. Alert for bone alterations and low serum concentrations of vitamin D in patients with intestinal inflammatory disease

    Directory of Open Access Journals (Sweden)

    Lorete Maria da Silva Kotze

    Full Text Available Summary Background: Inflammatory bowel diseases (IBD, including Crohn's disease (CD and ulcerative colitis (UC, are characterized by chronic inflammation of the intestine that can reduce the absorption of nutrients such as vitamin D and calcium. Objective: To investigate bone alterations and serum levels of vitamin D in patients with IBD. Method: This was a cross-sectional study based on a review of medical records of patients from a private office in Curitiba, PR, Brazil. Serum levels of vitamin D and bone densitometry were measured at diagnosis of IBD. A total of 105 patients were included; 38 (58.4% with CD; 27 (41.6% with UC and 40 with irritable bowel syndrome (IBS as comparison group. Results: When compared to patients with UC, CD patients showed a higher prevalence of bone alterations, being 15.8% with osteoporosis and 36.8% with osteopenia. In UC, bone alterations occurred in 29.6% of cases, 3.7% with osteoporosis and 25.9% with osteopenia. As for vitamin D levels, among CD patients, 10.5% had vitamin deficiency, 65.8% insufficiency and 23.7% were sufficient. In UC, 7.4% of cases had deficiency, 74.1% insufficiency and 18.5% had sufficient serum levels of vitamin D. In the group with IBS, deficiency was observed in 17.5% of cases, insufficiency in 55% and sufficiency in 27.5% of them. There was no significant difference between groups. Conclusion: IBD patients have a high prevalence of bone changes, especially those with CD. Serum levels of vitamin D are below the recommended in all the evaluated groups.

  13. Inclusions in bone material as a source of error in radiocarbon dating

    International Nuclear Information System (INIS)

    Hassan, A.A.; Ortner, D.J.

    1977-01-01

    Electron probe microanalysis, X-ray diffraction and microscopic examination were conducted on bone material from several archaeological sites in order to identify post-burial inclusions which, if present, may affect radiocarbon dating of bone. Two types of inclusions were identified: (1) precipitates from ground water solutions, and (2) solid intrusion. The first type consists of calcite, pyrite, humates and an unknown material. The second type includes quartz grains, hyphae, rootlets, wood and charcoal. Precipitation of calcite in a macro-molecular level in bone may lead to erroneaous dating of bone apatite if such calcite was not removed completely. A special technique, therefore, must be employed to remove calcite comletely. Hyphae and rootlets also are likely to induce errors in radiocarbon dating of bone collagen. These very fine inclusions require more than hand picking. (author)

  14. Neuroblastoma cells undergo transcriptomic alterations upon dissemination into the bone marrow and subsequent tumor progression.

    Science.gov (United States)

    Rifatbegovic, Fikret; Frech, Christian; Abbasi, M Reza; Taschner-Mandl, Sabine; Weiss, Tamara; Schmidt, Wolfgang M; Schmidt, Iris; Ladenstein, Ruth; Ambros, Inge M; Ambros, Peter F

    2018-01-15

    Neuroblastoma is the most common extracranial solid tumor in childhood. The vast majority of metastatic (M) stage patients present with disseminated tumor cells (DTCs) in the bone marrow (BM) at diagnosis and relapse. Although these cells represent a major obstacle in the treatment of neuroblastoma patients, insights into their expression profile remained elusive. The present RNA-Seq study of stage 4/M primary tumors, enriched BM-derived diagnostic and relapse DTCs, as well as the corresponding BM-derived mononuclear cells (MNCs) from 53 patients revealed 322 differentially expressed genes in DTCs as compared to the tumors (q 2). Particularly, the levels of transcripts encoded by mitochondrial DNA were elevated in DTCs, whereas, for example, genes involved in angiogenesis were downregulated. Furthermore, 224 genes were highly expressed in DTCs and only slightly, if at all, in MNCs (q  6). Interestingly, we found the transcriptome of relapse DTCs largely resembling those of diagnostic DTCs with only 113 differentially expressed genes under relaxed cut-offs (q 0.5). Notably, relapse DTCs showed a positional enrichment of 31 downregulated genes on chromosome 19, including five tumor suppressor genes: SIRT6, BBC3/PUMA, STK11, CADM4 and GLTSCR2. This first RNA-Seq analysis of neuroblastoma DTCs revealed their unique expression profile in comparison to the tumors and MNCs, and less pronounced differences between diagnostic and relapse DTCs. The latter preferentially affected downregulation of genes encoded by chromosome 19. As these alterations might be associated with treatment failure and disease relapse, further functional studies on DTCs should be considered. © 2017 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

  15. Materials and scaffolds in medical 3D printing and bioprinting in the context of bone regeneration.

    Science.gov (United States)

    Heller, Martin; Bauer, Heide-Katharina; Goetze, Elisabeth; Gielisch, Matthias; Ozbolat, Ibrahim T; Moncal, Kazim K; Rizk, Elias; Seitz, Hermann; Gelinsky, Michael; Schröder, Heinz C; Wang, Xiaohong H; Müller, Werner E G; Al-Nawas, Bilal

    The structural and functional repair of lost bone is still one of the biggest challenges in regenerative medicine. In many cases, autologous bone is used for the reconstruction of bone tissue; however, the availability of autologous material is limited, which always means additional stress to the patient. Due to this, more and more frequently various biocompatible materials are being used instead for bone augmentation. In this context, in order to ensure the structural function of the bone, scaffolds are implanted and fixed into the bone defect, depending on the medical indication. Nevertheless, for the surgeon, every individual clinical condition in which standardized scaffolds have to be aligned is challenging, and in many cases the alignment is not possible without limitations. Therefore, in the last decades, 3D printing (3DP) or additive manufacturing (AM) of scaffolds has become one of the most innovative approaches in surgery to individualize and improve the treatment of patients. Numerous biocompatible materials are available for 3DP, and various printing techniques can be applied, depending on the process conditions of these materials. Besides these conventional printing techniques, another promising approach in the context of medical AM is 3D bioprinting, a technique which makes it possible to print human cells embedded in special carrier substances to generate functional tissues. Even the direct printing into bone defects or lesions becomes possible. 3DP is already improving the treatment of patients, and has the potential to revolutionize regenerative medicine in future.

  16. MR-based trabecular bone microstructure is not altered in subjects with indolent systemic mastocytosis.

    Science.gov (United States)

    Baum, Thomas; Karampinos, Dimitrios C; Brockow, Knut; Seifert-Klauss, Vanadin; Jungmann, Pia M; Biedermann, Tilo; Rummeny, Ernst J; Bauer, Jan S; Müller, Dirk

    2015-01-01

    Subjects with indolent systemic mastocytosis (ISM) have an increased risk for osteoporosis. It has been demonstrated that trabecular bone microstructure analysis improves the prediction of bone strength beyond dual-energy X-ray absorptiometry-based bone mineral density. The purpose of this study was to obtain Magnetic Resonance (MR)-based trabecular bone microstructure parameters as advanced imaging biomarkers in subjects with ISM (n=18) and compare them with those of normal controls (n=18). Trabecular bone microstructure parameters were not significantly (P>.05) different between subjects with ISM and controls. These findings revealed important pathophysiological information about ISM-associated osteoporosis and may limit the use of trabecular bone microstructure analysis in this clinical setting. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Onlay bone augmentation on mouse calvarial bone using a hydroxyapatite/collagen composite material with total blood or platelet-rich plasma.

    Science.gov (United States)

    Ohba, Seigo; Sumita, Yoshinori; Umebayashi, Mayumi; Yoshimura, Hitoshi; Yoshida, Hisato; Matsuda, Shinpei; Kimura, Hideki; Asahina, Izumi; Sano, Kazuo

    2016-01-01

    The aim of this study was to assess newly formed onlay bone on mouse calvarial bone using a new artificial bone material, a hydroxyapatite/collagen composite, with total blood or platelet-rich plasma. The hydroxyapatite/collagen composite material with normal saline, total blood or platelet-rich plasma was transplanted on mouse calvarial bone. The mice were sacrificed and the specimens were harvested four weeks after surgery. The newly formed bone area was measured on hematoxylin and eosin stained specimens using Image J software. The hydroxyapatite/collagen composite materials with total blood or platelet-rich plasma induced a significantly greater amount of newly formed bone than that with normal saline. Moreover, bone marrow was observed four weeks after surgery in the transplanted materials with total blood or platelet-rich plasma but not with normal saline. However, there were no significant differences in the amount of newly formed bone between materials used with total blood versus platelet-rich plasma. The hydroxyapatite/collagen composite material was valid for onlay bone augmentation and this material should be soaked in total blood or platelet-rich plasma prior to transplantation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Ceramic and non-ceramic hydroxyapatite as a bone graft material: a brief review.

    Science.gov (United States)

    Dutta, S R; Passi, D; Singh, P; Bhuibhar, A

    2015-03-01

    Treatment of dental, craniofacial and orthopedic defects with bone graft substitutes has shown promising result achieving almost complete bone regeneration depending on product resorption similar to human bone's physicochemical and crystallographic characteristics. Among these, non-ceramic and ceramic hydroxyapatite being the main inorganic salt of bone is the most studied calcium phosphate material in clinical practices ever since 1970s and non-ceramic since 1985. Its "chemical similarity" with the mineralized phase of biologic bone makes it unique. Hydroxyapatite as an excellent carrier of osteoinductive growth factors and osteogenic cell populations is also useful as drug delivery vehicle regardless of its density. Porous ceramic and non-ceramic hydroxyapatite is osteoconductive, biocompatible and very inert. The need for bone graft material keeps on increasing with increased age of the population and the increased conditions of trauma. Recent advances in genetic engineering and doping techniques have made it possible to use non-ceramic hydroxyapatite in larger non-ceramic crystals and cluster forms as a successful bone graft substitute to treat various types of bone defects. In this paper we have mentioned some recently studied properties of hydroxyapatite and its various uses through a brief review of the literatures available to date.

  19. Analysis of Bone Meal (NIST 1486) and Bone Ash (NIST 1400) reference materials by neutron activation method; Analise de materiais de referencia Bone Meal (NIST 1486) e Bone Ash (NIST 1400) pelo metodo de ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Takata, Marcelo K.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Borelli, Aurelio [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina

    1999-11-01

    In this work instrumental neutron activation analysis has been applied to determine Ba, ca, Cl, Cr, fe, Mg, Mn, Na, P, Sb, Sc, Sr and Zn in two biological reference materials NIST 1486 Bone Meal and NIST 1400 Bone Ash. The purpose of this work was to evaluate the precision and the accuracy of the results as well as to give a contribution to certificate these materials. Interferences found in the determination of some elements were also discussed. (author) 8 refs., 4 tabs.

  20. Excessive growth hormone expression in male GH transgenic mice adversely alters bone architecture and mechanical strength.

    Science.gov (United States)

    Lim, S V; Marenzana, M; Hopkinson, M; List, E O; Kopchick, J J; Pereira, M; Javaheri, B; Roux, J P; Chavassieux, P; Korbonits, M; Chenu, C

    2015-04-01

    Patients with acromegaly have a higher prevalence of vertebral fractures despite normal bone mineral density (BMD), suggesting that GH overexpression has adverse effects on skeletal architecture and strength. We used giant bovine GH (bGH) transgenic mice to analyze the effects of high serum GH levels on BMD, architecture, and mechanical strength. Five-month-old hemizygous male bGH mice were compared with age- and sex-matched nontransgenic littermates controls (NT; n=16/group). Bone architecture and BMD were analyzed in tibia and lumbar vertebrae using microcomputed tomography. Femora were tested to failure using three-point bending and bone cellular activity determined by bone histomorphometry. bGH transgenic mice displayed significant increases in body weight and bone lengths. bGH tibia showed decreases in trabecular bone volume fraction, thickness, and number compared with NT ones, whereas trabecular pattern factor and structure model index were significantly increased, indicating deterioration in bone structure. Although cortical tissue perimeter was increased in transgenic mice, cortical thickness was reduced. bGH mice showed similar trabecular BMD but reduced trabecular thickness in lumbar vertebra relative to controls. Cortical BMD and thickness were significantly reduced in bGH lumbar vertebra. Mechanical testing of femora confirmed that bGH femora have decreased intrinsic mechanical properties compared with NT ones. Bone turnover is increased in favor of bone resorption in bGH tibia and vertebra compared with controls, and serum PTH levels is also enhanced in bGH mice. These data collectively suggest that high serum GH levels negatively affect bone architecture and quality at multiple skeletal sites.

  1. High resolution bone material property assignment yields robust subject specific finite element models of complex thin bone structures.

    Science.gov (United States)

    Pakdel, Amirreza; Fialkov, Jeffrey; Whyne, Cari M

    2016-06-14

    Accurate finite element (FE) modeling of complex skeletal anatomy requires high resolution in both meshing and the heterogeneous mapping of material properties onto the generated mesh. This study introduces Node-based elastic Modulus Assignment with Partial-volume correction (NMAP) as a new approach for FE material property assignment to thin bone structures. The NMAP approach incorporates point spread function based deblurring of CT images, partial-volume correction of CT image voxel intensities and anisotropic interpolation and mapping of CT intensity assignment to FE mesh nodes. The NMAP procedure combined with a derived craniomaxillo-facial skeleton (CMFS) specific density-isotropic elastic modulus relationship was applied to produce specimen-specific FE models of 6 cadaveric heads. The NMAP procedure successfully generated models of the complex thin bone structures with surface elastic moduli reflective of cortical bone material properties. The specimen-specific CMFS FE models were able to accurately predict experimental strains measured under in vitro temporalis and masseter muscle loading (r=0.93, slope=1.01, n=5). The strength of this correlation represents a robust validation for CMFS FE modeling that can be used to better understand load transfer in this complex musculoskeletal system. The developed methodology offers a systematic process-flow able to address the complexity of the CMFS that can be further applied to create high-fidelity models of any musculoskeletal anatomy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. 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.

  3. Altered Osteocyte-Specific Protein Expression in Bone after Childhood Solid Organ Transplantation.

    Science.gov (United States)

    Pereira, Renata C; Valta, Helena; Tumber, Navdeep; Salusky, Isidro B; Jalanko, Hannu; Mäkitie, Outi; Wesseling Perry, Katherine

    2015-01-01

    Bone fragility is common post solid organ transplantation but little is known about bone pathology on a tissue level. Abnormal osteocytic protein expression has been linked to compromised bone health in chronic kidney disease (CKD) and immunosuppressant medications may impact osteocyte function. Transiliac bone biopsies were obtained from 22 pediatric solid organ allograft recipients (average age 15.6 years) an average of 6.3 ± 1.2 years after transplantation and from 12 pediatric pre-dialysis CKD patients (average age 13.2 years). Histomorphometry and immunohistochemistry for FGF23, DMP1, sclerostin, and osteopontin were performed on all biopsies. FGF23 and sclerostin were increased in transplant recipients relative to non-transplant CKD, regardless of the type of allograft received and despite, in the case of liver and heart recipients, a higher GFR. Bone DMP1 expression was higher in liver or heart than in kidney recipients, concomitant with higher serum phosphate values. Osteopontin expression was higher in CKD than in transplant recipients (pBone FGF23 and sclerostin correlated directly (r = 0.38, pbone FGF23 expression and osteoid thickness correlated inversely (r = - 0.46, ptransplantation is associated with increased FGF23 and sclerostin expression. The contribution of these findings to compromised bone health post transplantation warrants further evaluation.

  4. Dietary patterns in men and women are simultaneously determinants of altered glucose metabolism and bone metabolism.

    Science.gov (United States)

    Langsetmo, Lisa; Barr, Susan I; Dasgupta, Kaberi; Berger, Claudie; Kovacs, Christopher S; Josse, Robert G; Adachi, Jonathan D; Hanley, David A; Prior, Jerilynn C; Brown, Jacques P; Morin, Suzanne N; Davison, Kenneth S; Goltzman, David; Kreiger, Nancy

    2016-04-01

    We hypothesized that diet would have direct effects on glucose metabolism with direct and indirect effects on bone metabolism in a cohort of Canadian adults. We assessed dietary patterns (Prudent [fruit, vegetables, whole grains, fish, and legumes] and Western [soft drinks, potato chips, French fries, meats, and desserts]) from a semiquantitative food frequency questionnaire. We used fasting blood samples to measure glucose, insulin, homeostatic model assessment insulin resistance (HOMA-IR), 25-hydroxyvitamin D (25OHD), parathyroid hormone, bone-specific alkaline phosphatase (a bone formation marker), and serum C-terminal telopeptide (CTX; a bone resorption marker). We used multivariate regression models adjusted for confounders and including/excluding body mass index. In a secondary analysis, we examined relationships through structural equations models. The Prudent diet was associated with favorable effects on glucose metabolism (lower insulin and HOMA-IR) and bone metabolism (lower CTX in women; higher 25OHD and lower parathyroid hormone in men). The Western diet was associated with deleterious effects on glucose metabolism (higher glucose, insulin, and HOMA-IR) and bone metabolism (higher bone-specific alkaline phosphatase and lower 25OHD in women; higher CTX in men). Body mass index adjustment moved point estimates toward the null, indicating partial mediation. The structural equation model confirmed the hypothesized linkage with strong effects of Prudent and Western diet on metabolic risk, and both direct and indirect effects of a Prudent diet on bone turnover. In summary, a Prudent diet was associated with lower metabolic risk with both primary and mediated effects on bone turnover, suggesting that it is a potential target for reducing fracture risk. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Macroscopic anisotropic bone material properties in children with severe osteogenesis imperfecta.

    Science.gov (United States)

    Albert, Carolyne; Jameson, John; Tarima, Sergey; Smith, Peter; Harris, Gerald

    2017-11-07

    Children with severe osteogenesis imperfecta (OI) typically experience numerous fractures and progressive skeletal deformities over their lifetime. Recent studies proposed finite element models to assess fracture risk and guide clinicians in determining appropriate intervention in children with OI, but lack of appropriate material property inputs remains a challenge. This study aimed to characterize macroscopic anisotropic cortical bone material properties and investigate relationships with bone density measures in children with severe OI. Specimens were obtained from tibial or femoral shafts of nine children with severe OI and five controls. The specimens were cut into beams, characterized in bending, and imaged by synchrotron radiation X-ray micro-computed tomography. Longitudinal modulus of elasticity, yield strength, and bending strength were 32-65% lower in the OI group (p<0.001). Yield strain did not differ between groups (p≥0.197). In both groups, modulus and strength were lower in the transverse direction (p≤0.009), but anisotropy was less pronounced in the OI group. Intracortical vascular porosity was almost six times higher in the OI group (p<0.001), but no differences were observed in osteocyte lacunar porosity between the groups (p=0.086). Volumetric bone mineral density was lower in the OI group (p<0.001), but volumetric tissue mineral density was not (p=0.770). Longitudinal OI bone modulus and strength were correlated with volumetric bone mineral density (p≤0.024) but not volumetric tissue mineral density (p≥0.099). Results indicate that cortical bone in children with severe OI yields at the same strain as normal bone, and that their decreased bone material strength is associated with reduced volumetric bone mineral density. These results will enable the advancement of fracture risk assessment capability in children with severe OI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Is Graphene a Promising Nano-Material for Promoting Surface Modification of Implants or Scaffold Materials in Bone Tissue Engineering?

    Science.gov (United States)

    Gu, Ming; Liu, Yunsong; Chen, Tong; Du, Feng; Zhao, Xianghui; Xiong, Chunyang

    2014-01-01

    Bone tissue engineering promises to restore bone defects that are caused by severe trauma, congenital malformations, tumors, and nonunion fractures. How to effectively promote the proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) or seed cells has become a hot topic in this field. Many researchers are studying the ways of conferring a pro-osteodifferentiation or osteoinductive capability on implants or scaffold materials, where osteogenesis of seed cells is promoted. Graphene (G) provides a new kind of coating material that may confer the pro-osteodifferentiation capability on implants and scaffold materials by surface modification. Here, we review recent studies on the effects of graphene on surface modifications of implants or scaffold materials. The ability of graphene to improve the mechanical and biological properties of implants or scaffold materials, such as nitinol and carbon nanotubes, and its ability to promote the adhesion, proliferation, and osteogenic differentiation of MSCs or osteoblasts have been demonstrated in several studies. Most previous studies were performed in vitro, but further studies will explore the mechanisms of graphene's effects on bone regeneration, its in vivo biocompatibility, its ability to promote osteodifferentiation, and its potential applications in bone tissue engineering. PMID:24447041

  7. Is graphene a promising nano-material for promoting surface modification of implants or scaffold materials in bone tissue engineering?

    Science.gov (United States)

    Gu, Ming; Liu, Yunsong; Chen, Tong; Du, Feng; Zhao, Xianghui; Xiong, Chunyang; Zhou, Yongsheng

    2014-10-01

    Bone tissue engineering promises to restore bone defects that are caused by severe trauma, congenital malformations, tumors, and nonunion fractures. How to effectively promote the proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) or seed cells has become a hot topic in this field. Many researchers are studying the ways of conferring a pro-osteodifferentiation or osteoinductive capability on implants or scaffold materials, where osteogenesis of seed cells is promoted. Graphene (G) provides a new kind of coating material that may confer the pro-osteodifferentiation capability on implants and scaffold materials by surface modification. Here, we review recent studies on the effects of graphene on surface modifications of implants or scaffold materials. The ability of graphene to improve the mechanical and biological properties of implants or scaffold materials, such as nitinol and carbon nanotubes, and its ability to promote the adhesion, proliferation, and osteogenic differentiation of MSCs or osteoblasts have been demonstrated in several studies. Most previous studies were performed in vitro, but further studies will explore the mechanisms of graphene's effects on bone regeneration, its in vivo biocompatibility, its ability to promote osteodifferentiation, and its potential applications in bone tissue engineering.

  8. Development of a Moldable, Biodegradable Polymeric Bone Repair Material

    Science.gov (United States)

    1994-03-30

    26% Cellulose 2 85% PCL 1250 15% Calcium Carbonate 2 85% PCL 1250 15% Carnauba Wax 3 80% PCL 1250 20% Carboxymethyl 4 Cellulose 85% PCL 1250 15% Gum...Tragacanth 4 83% PCL 1250 17% Gelatin 5 83% PCL 1250 17% Gum Xanthan 7 79% PCL 2000 21% Carnauba Wax 7 85% PCL 2000 15% Calcium Stearate 7 83% PLA 2000...azaum 200 wo ) After the revision of the statement of work, the objective of this contract was the development of a biodegradable bone wax . It would be

  9. 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)

  10. Surface materials map of Afghanistan: carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Dudek, Kathleen B.; Livo, Keith E.

    2012-01-01

    This map shows the distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of HyMap imaging spectrometer data of Afghanistan. Using a NASA (National Aeronautics and Space Administration) WB-57 aircraft flown at an altitude of ~15,240 meters or ~50,000 feet, 218 flight lines of data were collected over Afghanistan between August 22 and October 2, 2007. The HyMap data were converted to apparent surface reflectance, then further empirically adjusted using ground-based reflectance measurements. The reflectance spectrum of each pixel of HyMap data was compared to the spectral features of reference entries in a spectral library of minerals, vegetation, water, ice, and snow. This map shows the spatial distribution of minerals that have diagnostic absorption features in the shortwave infrared wavelengths. These absorption features result primarily from characteristic chemical bonds and mineralogical vibrations. Several criteria, including (1) the reliability of detection and discrimination of minerals using the HyMap spectrometer data, (2) the relative abundance of minerals, and (3) the importance of particular minerals to studies of Afghanistan's natural resources, guided the selection of entries in the reference spectral library and, therefore, guided the selection of mineral classes shown on this map. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated. Minerals having similar spectral features were less easily discriminated, especially where the minerals were not particularly abundant and (or) where vegetation cover reduced the absorption strength of mineral features. Complications in reflectance calibration also affected the detection and identification of minerals.

  11. Development of bone-lead reference materials for validating in vivo XRF measurements

    International Nuclear Information System (INIS)

    Parsons, P.J.; Zong, Y.Y.; Matthews, M. R.

    1995-01-01

    A number of biological reference materials (RM) have been prepared in our laboratory specifically for validating analytical methods for the determination of Pb in biological matrices (e.g. blood, urine, liver, and bone). The RM's were developed using animal (goats and cows) that are routinely dosed with lead acetate to produce proficiency test samples for blood lead (and erythrocyte protoporphyrin). In cases where an animal becomes injured or infirm, the veterinarian in charge may recommend that the animal be euthanized. In such cases, samples of bone, brain, liver, and other tissues containing lead are removed at autopsy. Currently, we have collected bone samples from nine goats and one cow that were dosed with lead over periods ranging from 1 to 10 years. During the autopsy, the epiphyses (bone joints) are separated from each long bone. Skin, muscle, and other adhering tissues are dissected or scraped from each bone. Bone marrow is also removed. All bare bones are currently stored at -70 degrees C until analyses for Pb are conducted

  12. Maxillary Sinus Floor Augmentation With Synthetic Bone Substitutes Compared With Other Grafting Materials

    DEFF Research Database (Denmark)

    Starch-Jensen, Thomas; Mordenfeld, Arne; Becktor, Jonas Peter

    2018-01-01

    OBJECTIVE: To test the hypotheses of no differences in implant treatment outcome after maxillary sinus floor augmentation (MSFA) with synthetic bone substitutes (SBS) compared with other grafting materials applying the lateral window technique. MATERIALS AND METHODS: A MEDLINE/PubMed, Embase and ...

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

    International Nuclear Information System (INIS)

    Piccirillo, C.; Silva, M.F.; Pullar, R.C.; Braga da Cruz, I.; Jorge, R.; Pintado, M.M.E.; Castro, P.M.L.

    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 °C, giving a biphasic material of hydroxyapatite and tricalcium phosphate (Ca 10 (PO 4 ) 6 (OH) 2 and β-Ca(PO 4 ) 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 10 (PO 4 ) 6 Cl 2 ) and fluorapatite (Ca 10 (PO 4 ) 6 F 2 ) were obtained using CaCl 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: ► Apatite and calcium phosphate compounds extraction from cod fish bonesBone calcination: biphasic material hydroxyapatite-calcium phosphate production ► Bone pre-treatments in solution change the material composition. ► Single phase materials (hydroxy-, chloro- or fluoroapatite) are obtained. ► Concentration of other elements (Na, F, Cl) suitable for biomedical applications

  14. 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.

  15. 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 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.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.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.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 tissue mineral density, as well as

  16. Alterations to Bone Mineral Composition as an Early Indication of Osteomyelitis in the Diabetic Foot

    OpenAIRE

    Esmonde-White, Karen A.; Esmonde-White, Francis W.L.; Holmes, Crystal M.; Morris, Michael D.; Roessler, Blake J.

    2013-01-01

    OBJECTIVE Osteomyelitis in the diabetic foot is a major risk factor for amputation, but there is a limited understanding of early-stage infection, impeding limb-preserving diagnoses. We hypothesized that bone composition measurements provide insight into the early pathophysiology of diabetic osteomyelitis. RESEARCH DESIGN AND METHODS Compositional analysis by Raman spectroscopy was performed on bone specimens from patients with a clinical diagnosis of osteomyelitis in the foot requiring surgi...

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

    Science.gov (United States)

    Settem, Rajendra P; Honma, Kiyonobu; Sharma, Ashu

    2014-01-01

    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. 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.

  19. Composite resin as an implant material in bone. Histologic, radiologic, microradiologic and oxytetracycline fluorescence examination of rats

    Energy Technology Data Exchange (ETDEWEB)

    Vainio, J; Rokkanen, P [Tampere Univ. (Finland). Inst. of Clinical Sciences; Central Hospital, Tampere (Finland))

    1978-01-01

    The potential of a bis-GMA composite resin as implant material in bone is evaluated. The material is claimed to have mechanical and physical properties superior to those of the bone cements used today. A groove made in the cortex of the tibia in 18 rats was filled with bis-GMA, while a similar was left empty in the contralateral tibia. The reaction of the bone to this material was evaluated by histologic, radiologic, microradiograph and OTC-fluorescence methods. The material was well tolerated by the bone; after 1,3 and 6 weeks no reaction to the material was observed.

  20. Histological analysis of the alterations on cortical bone channels network after radiotherapy: A rabbit study.

    Science.gov (United States)

    Rabelo, Gustavo Davi; Beletti, Marcelo Emílio; Dechichi, Paula

    2010-10-01

    The aim of this study was to evaluate the effects of radiotherapy in cortical bone channels network. Fourteen rabbits were divided in two groups and test group received single dose of 15 Gy cobalt-60 radiation in tibia, bilaterally. The animals were sacrificed and a segment of tibia was removed and histologically processed. Histological images were taken and had their bone channels segmented and called regions of interest (ROI). Images were analyzed through developed algorithms using the SCILAB mathematical environment, getting percentage of bone matrix, ROI areas, ROI perimeters, their standard deviations and Lacunarity. The osteocytes and empty lacunae were also counted. Data were evaluated using Kolmogorov-Smirnov, Mann Whitney, and Student's t test (P < 0.05). Significant differences in bone matrix percentage, area and perimeters of the channels, their respective standard deviations and lacunarity were found between groups. In conclusion, the radiotherapy causes reduction of bone matrix and modifies the morphology of bone channels network. © 2010 Wiley-Liss, Inc.

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

    Czech Academy of Sciences Publication Activity Database

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

    2014-01-01

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

  2. Rib fractures in chronic alcoholic men: Relationship with feeding habits, social problems, malnutrition, bone alterations, and liver dysfunction.

    Science.gov (United States)

    González-Reimers, Emilio; García-Valdecasas-Campelo, Elena; Santolaria-Fernández, Francisco; Milena-Abril, Antonio; Rodríguez-Rodríguez, Eva; Martínez-Riera, Antonio; Pérez-Ramírez, Alina; Alemán-Valls, María Remedios

    2005-10-01

    Rib fractures are common in alcoholics. This high prevalence might be due to ethanol-associated malnutrition, bone disease, liver dysfunction, or the peculiar lifestyle of the alcoholic with frequent trauma and altercations. In this study we try to discern the role of these factors on rib fracture (assessed on a plain thoracic X-ray film) in 81 consecutive alcoholic patients, 25 of them cirrhotics. Serum albumin, prothrombin aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), gamma-glutamyl transpeptidase, C-terminal cross-linking telopeptide of type 1 collagen, osteocalcin, insulin growth factor 1, 1,25-dihydroxyvitamin D, parathyroid hormone, estradiol, free testosterone, and corticosterone were measured, and the patients also underwent assessment of bone mineral density by a HOLOGIC QDR-2000 bone densitometer (Waltham, MA, USA). Body mass index, triceps skinfold, and brachial perimeter were also determined, and the patients and their families were asked about tobacco consumption, social and familial links, consumption of ethanol by other members of the family, kind of job, and feeding habits. Forty-two male nondrinker sanitary workers of similar age served as controls. Forty of the 81 patients showed rib fractures. There was a statistically significant association between rib fractures and disruption of social and familial links, irregular feeding habits (in bars or pubs, not at home), ethanol consumption by close relatives, and intensity of tobacco consumption, but not between rib fractures and liver function tests, nutritional parameters, or bone mineral density, besides a nearly significant trend (p = .053) with the presence of osteopenia at the femoral neck. Patients with major withdrawal symptoms at admission also presented more frequent rib fractures. We conclude that rib fractures in alcoholics are related to the peculiar lifestyle of these patients rather than to bone alterations, liver dysfunction, or nutritional status.

  3. 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.

  4. 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

  5. The Effect of Reduced Graphene Oxide-Coated Biphasic Calcium Phosphate Bone Graft Material on Osteogenesis.

    Science.gov (United States)

    Kim, Jeong-Woo; Shin, Yong Cheol; Lee, Jin-Ju; Bae, Eun-Bin; Jeon, Young-Chan; Jeong, Chang-Mo; Yun, Mi-Jung; Lee, So-Hyoun; Han, Dong-Wook; Huh, Jung-Bo

    2017-08-08

    This study was conducted to evaluate the effect of biphasic calcium phosphate (BCP) coated with reduced graphene oxide (rGO) as bone graft materials on bone regeneration. The rGO-coated BCP bone graft material was fabricatied by mixing rGO and BCP at various concentrations. The surface charge of rGO-coated BCP was measured to be -14.43 mV, which formed a static electrostatic interaction. Cell viabilities were significantly diminished at higher concentrations of ≥100 μg/mL. The calvarial defects of 48 rats were implanted rGO-coated BCPs at a weight ratio of 2:1000 (rGO2), 4:1000 (rGO4), and 10:1000 (rGO10), repectively. BCP was used as a control group. The micro-CT and histological analysis were performed to evaluate new bone formation at 2 and 8 weeks after surgery. The results showed that the new bone volume (mm³) was significantly higher in the experimental groups than in the control group. Histological analysis showed that new bone areas (%) were significantly higher in the rGO2 and rGO10 than in the control, and significantly higher in rGO4 than in the rGO2 and rGO10. Conclusively, the rGO-coated BCP was found to be effective on osteogenesis and the concentration of the composite was an important factor.

  6. Investigation of novel bioactive rapidly resorbable bone substitute materials and their influence on osteoblastic cell differentiation in vivo

    OpenAIRE

    Jonscher, Sebastian

    2010-01-01

    Among the various techniques to reconstruct or enlarge a deficient alveolar ridge, the concept of guided bone regeneration (GBR) has become a predictable and well-documented surgical approach. At present, autogenous bone grafts are preferably combined with barrier membranes. Using synthetic biodegradable bone substitute materials, however, is advantageous, since it avoids second-site surgery for autograft harvesting. A bone substitute for alveolar ridge augmentation must be rapidly resorbable...

  7. Content Validity of Temporal Bone Models Printed Via Inexpensive Methods and Materials.

    Science.gov (United States)

    Bone, T Michael; Mowry, Sarah E

    2016-09-01

    Computed tomographic (CT) scans of the 3-D printed temporal bone models will be within 15% accuracy of the CT scans of the cadaveric temporal bones. Previous studies have evaluated the face validity of 3-D-printed temporal bone models designed to train otolaryngology residents. The purpose of the study was to determine the content validity of temporal bone models printed using inexpensive printers and materials. Four cadaveric temporal bones were randomly selected and clinical temporal bone CT scans were obtained. Models were generated using previously described methods in acrylonitrile butadiene styrene (ABS) plastic using the Makerbot Replicator 2× and Hyrel printers. Models were radiographically scanned using the same protocol as the cadaveric bones. Four images from each cadaveric CT series and four corresponding images from the model CT series were selected, and voxel values were normalized to black or white. Scan slices were compared using PixelDiff software. Gross anatomic structures were evaluated in the model scans by four board certified otolaryngologists on a 4-point scale. Mean pixel difference between the cadaver and model scans was 14.25 ± 2.30% at the four selected CT slices. Mean cortical bone width difference and mean external auditory canal width difference were 0.58 ± 0.66 mm and 0.55 ± 0.46 mm, respectively. Expert raters felt the mastoid air cells were well represented (2.5 ± 0.5), while middle ear and otic capsule structures were not accurately rendered (all averaged bones for training residents in cortical mastoidectomies, but less effective for middle ear procedures.

  8. Material heterogeneity in cancellous bone promotes deformation recovery after mechanical failure.

    Science.gov (United States)

    Torres, Ashley M; Matheny, Jonathan B; Keaveny, Tony M; Taylor, David; Rimnac, Clare M; Hernandez, Christopher J

    2016-03-15

    Many natural structures use a foam core and solid outer shell to achieve high strength and stiffness with relatively small amounts of mass. Biological foams, however, must also resist crack growth. The process of crack propagation within the struts of a foam is not well understood and is complicated by the foam microstructure. We demonstrate that in cancellous bone, the foam-like component of whole bones, damage propagation during cyclic loading is dictated not by local tissue stresses but by heterogeneity of material properties associated with increased ductility of strut surfaces. The increase in surface ductility is unexpected because it is the opposite pattern generated by surface treatments to increase fatigue life in man-made materials, which often result in reduced surface ductility. We show that the more ductile surfaces of cancellous bone are a result of reduced accumulation of advanced glycation end products compared with the strut interior. Damage is therefore likely to accumulate in strut centers making cancellous bone more tolerant of stress concentrations at strut surfaces. Hence, the structure is able to recover more deformation after failure and return to a closer approximation of its original shape. Increased recovery of deformation is a passive mechanism seen in biology for setting a broken bone that allows for a better approximation of initial shape during healing processes and is likely the most important mechanical function. Our findings suggest a previously unidentified biomimetic design strategy in which tissue level material heterogeneity in foams can be used to improve deformation recovery after failure.

  9. 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 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.

  10. Dynamic alterations of bone marrow cytokine landscape of myelodysplastic syndromes patients treated with 5-azacytidine

    Czech Academy of Sciences Publication Activity Database

    Moudra, A.; Hubackova, Sona; Machalova, V.; Vančurová, M.; Bartek, J.; Reinis, M.; Hodny, Z.; Jonasova, A.

    2016-01-01

    Roč. 5, č. 10 (2016), č. článku e1183860. ISSN 2162-402X Institutional support: RVO:86652036 Keywords : 5-azacytidine * DNA damage * cytokines * bone marrow plasma Subject RIV: FD - Oncology ; Hematology Impact factor: 7.719, year: 2016

  11. Dynamic alterations of bone marrow cytokine landscape of myelodysplastic syndromes patients treated with 5-azacytidine

    Czech Academy of Sciences Publication Activity Database

    Moudrá, Alena; Hubáčková, Soňa; Machalová, Veronika; Vančurová, Markéta; Bartek, Jiří; Reiniš, Milan; Hodný, Zdeněk; Jonasova, A.

    2016-01-01

    Roč. 5, č. 10 (2016), č. článku e1183860. ISSN 2162-402X R&D Projects: GA MZd NT14174 Institutional support: RVO:68378050 Keywords : 5-azacyatidine * bone marrow plasma * cytokines * DNA damage * inflammation * myelodysplastic syndromes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.719, year: 2016

  12. 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 i...

  13. Sinus Floor Elevation and Augmentation Using Synthetic Nanocrystalline and Nanoporous Hydroxyapatite Bone Substitute Materials: Preliminary Histologic Results.

    Science.gov (United States)

    Belouka, Sofia-Maria; Strietzel, Frank Peter

    To compare the tissue composition of augmented sites after using two different synthetic bone substitute materials, nanocrystalline and nanoporous hydroxyapatite (HA), for sinus floor elevation and augmentation. Forty-four patients received 88 titanium screw implants (Camlog Promote plus) of 4.3-mm diameter and 11- or 13-mm length, placed simultaneously during sinus floor elevation and augmentation. Nanocrystalline (Ostim) or nanoporous (NanoBone) HA were used exclusively. Bone substitute materials and implant lengths were allocated by randomization. Bone biopsy specimens were obtained from the former area of the lateral access window at implant exposure during healing abutment placement after 6 months. Biopsy specimens were prepared and examined histologically and histomorphometrically. All implants were osseointegrated at the time of exposure. Clinically and histologically, no signs of inflammation in the augmented sites were present. The histomorphometric analysis of 44 biopsy specimens revealed 31.8% ± 11.6% newly formed bone for sites augmented with nanocrystalline HA and 34.6% ± 9.2% for nanoporous HA (P = .467). The proportion of remaining bone substitute material was 28.4% ± 18.6% and 30% ± 13%, respectively (P = .453). The proportion of soft tissue within the biopsy specimens was 39.9% ± 11.1% and 35.4% ± 6.8%, respectively (P = .064). No significant differences were found between the area fractions of bone, bone substitute material, and soft tissue concerning the bone substitute material utilized. Within the present study, both synthetic bone substitute materials, nanocrystalline and nanoporous HA, were found to support bone formation in sinus floor elevation and augmentation procedures by osteoconductivity. They were not completely resorbed after 6 months. The amounts of newly formed bone, soft tissue, and bone substitute material remnants were found to be similar, indicating that both materials are likewise suitable for sinus floor elevation and

  14. Characterisation of β-tricalcium phosphate-based bone substitute materials by electron paramagnetic resonance spectroscopy

    Science.gov (United States)

    Matković, Ivo; Maltar-Strmečki, Nadica; Babić-Ivančić, Vesna; Dutour Sikirić, Maja; Noethig-Laslo, Vesna

    2012-10-01

    β-TCP based materials are frequently used as dental implants. Due to their resorption in the body and direct contact with tissues, in order to inactivate bacteria, fungal spores and viruses, they are usually sterilized by γ-irradiation. However, the current literature provides little information about effects of the γ-irradiation on the formation and stability of the free radicals in the bone graft materials during and after sterilization procedure. In this work five different bone graft substitution materials, composed of synthetic beta tricalcium phosphate (β-TCP) and hydroxyapatite (HAP) present in the market were characterized by electron paramagnetic resonance (EPR) spectroscopy, X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Paramagnetic species Mn2+, Fe3+, trapped H-atoms and CO2- radicals were detected in the biphasic material (60% HAP, 40% β-TCP), while in β-TCP materials only Mn2+ andor trapped hydrogen atoms were detected. EPR analysis revealed the details of the structure of these materials at the atomic level. The results have shown that EPR spectroscopy is a method which can be used to improve the quality control of bone graft materials after syntering, processing and sterilization procedure.

  15. Reactions and Surface Transformations of a Bone-Bioactive Material in a Simulated Microgravity Environment

    Science.gov (United States)

    Radin, S.; Ducheyne, P.; Ayyaswamy, P. S.

    1999-01-01

    A comprehensive program to investigate the expeditious in vitro formation of three-dimensional bone-like tissue is currently underway at the University of Pennsylvania. The study reported here forms a part of that program. Three-dimensional bone-like tissue structures may be grown under the simulated microgravity conditions of NASA designed Rotating Wall Bioreactor Vessels (RWV's). Such tissue growth will have wide clinical applications. In addition, an understanding of the fundamental changes that occur to bone cells under simulated microgravity would yield important information that will help in preventing or minimizing astronaut bone loss, a major health issue with travel or stay in space over long periods of time. The growth of three-dimensional bone-like tissue structures in RWV's is facilitated by the use of microcarriers which provide structural support. If the microcarrier material additionally promotes bone cell growth, then it is particularly advantageous to employ such microcarriers. We have found that reactive, bone-bioactive glass (BBG) is an attractive candidate for use as microcarrier material. Specifically, it has been found that BBG containing Ca- and P- oxides upregulates osteoprogenitor cells to osteoblasts. This effect on cells is preceded by BBG reactions in solution which result in the formation of a Ca-P surface layer. This surface further transforms to a bone-like mineral (i.e., carbonated crystalline hydroxyapatite (c-HA)). At normal gravity, time-dependent, immersion-induced BBG reactions and transformations are greatly affected both by variations in the composition of the milieu in which the glass is immersed and on the immersion conditions. However, the nature of BBG reactions and phase transformations under the simulated microgravity conditions of RWV's are unknown, and must be understood in order to successfully use BBG as microcarrier material in RWV'S. In this paper, we report some of our recent findings in this regard using

  16. Comparison of the effectiveness of two different bone substitute materials for socket preservation after tooth extraction: a controlled clinical study.

    Science.gov (United States)

    Shakibaie-M, Behnam

    2013-01-01

    The aim of this study was to compare the effectiveness of two bone substitute materials for socket preservation after tooth extraction. Extraction sockets in 10 patients were filled with either inorganic bovine bone material (Bio-Oss) or with synthetic material consisting of hydroxyapatite and silicon dioxide (NanoBone). Extraction sockets without filling served as the control. The results demonstrate the effectiveness of the presented protocol for socket preservation and that the choice of a suitable bone substitute material is crucial. The dimensions of the alveolar ridge were significantly better preserved with Bio-Oss than with NanoBone or without treatment. Bio-Oss treatment resulted in better bone quality and quantity for successful implant placement.

  17. Effect of Flapless Immediate Implantation and Filling the Buccal Gap with Xenograft Material on the Buccal Bone Level: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Mojgan Paknejad

    2017-12-01

    Full Text Available Objectives: Following tooth extraction, soft and hard tissue alterations occur; Different factors can affect this process. The objective of this study was to determine the effect of gap filling on buccal alveolar crestal bone level after immediate implant placement after 4- to 6-month observation period.Materials and Methods: This   randomized clinical trial was performed on 20 patients (mean age of 38.8 years requiring tooth extraction in a total of 27 areas in the anterior maxilla. The treatment strategy was as follows: atraumatic flapless tooth extraction, implant placement, insertion of a graft (test group or no material (control group between the implant and the socket wall, connection healing abutment placement and suturing the area. Clinical and cone beam computed tomographic examinations were performed before implant placement (baseline, 24 hours after surgery and 4-6 months (T2 after implant placement, to assess the buccal plate height (BH and implant complications.Results: After 4 months of healing, a reduction in different bone measurements was noticed in the two groups. No statistically significant differences were assessed in bone height measurements between the test and control groups at different time points. The study demonstrated that immediate implantation resulted in 1.30 and 1.66 mm reduction in buccal bone plate in the test and control groups, respectively.Conclusions: The study demonstrated that immediate implantation in the extraction socket together with xenograft failed to prevent bone resorption.

  18. 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...

  19. Fixation strength analysis of cup to bone material using finite element simulation

    NARCIS (Netherlands)

    Anwar, Iwan Budiwan; Saputra, Eko; Ismail, Rifky; Jamari, J.; Van Der Heide, Emile

    2016-01-01

    Fixation of acetabular cup to bone material is an important initial stability for artificial hip joint. In general, the fixation in cement less-type acetabular cup uses press-fit and screw methods. These methods can be applied alone or together. Based on literature survey, the additional screw

  20. Assessment of compressive failure process of cortical bone materials using damage-based model.

    Science.gov (United States)

    Ng, Theng Pin; R Koloor, S S; Djuansjah, J R P; Abdul Kadir, M R

    2017-02-01

    The main failure factors of cortical bone are aging or osteoporosis, accident and high energy trauma or physiological activities. However, the mechanism of damage evolution coupled with yield criterion is considered as one of the unclear subjects in failure analysis of cortical bone materials. Therefore, this study attempts to assess the structural response and progressive failure process of cortical bone using a brittle damaged plasticity model. For this reason, several compressive tests are performed on cortical bone specimens made of bovine femur, in order to obtain the structural response and mechanical properties of the material. Complementary finite element (FE) model of the sample and test is prepared to simulate the elastic-to-damage behavior of the cortical bone using the brittle damaged plasticity model. The FE model is validated in a comparative method using the predicted and measured structural response as load-compressive displacement through simulation and experiment. FE results indicated that the compressive damage initiated and propagated at central region where maximum equivalent plastic strain is computed, which coincided with the degradation of structural compressive stiffness followed by a vast amount of strain energy dissipation. The parameter of compressive damage rate, which is a function dependent on damage parameter and the plastic strain is examined for different rates. Results show that considering a similar rate to the initial slope of the damage parameter in the experiment would give a better sense for prediction of compressive failure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Electron beam irradiation to the allogeneic, xenogenic and synthetic bone materials

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soung Min; Park, Min Woo; Jeong, Hyun Oh [School of Dentistry Seoul National University, Seoul (Korea, Republic of); and others

    2013-07-01

    For the development of the biocompatible bony regeneration materials, allogenic, xenogenic and synthetic bone were irradiated by electron beam to change the basic components and structures. For the efficient electron beam irradiating condition of these allogenic, xenogenic and artificial bone substitutes, the optimal electron beam energy and their individual dose were established, to maximize the bony regeneration capacity. Commercial products of four allogenic bones, such as Accell (ISOTIS OrthogBiologics Co., USA), Allotis (Korea Bone Bank Co., Korea), Oragraft (LifeNet Co., USA), and Orthoblast (Integra Orthobiologics Inc., USA), six xenogenic bones, such as BBP (OscoTec Co., Korea), Bio-cera (OscoTec Co., Korea), Bio-oss (Geistlich Pharma AG, Switzerland), Indu-cera (OscoTec Co., Korea), OCS-B (Nibec Co., Korea), and OCS-H (Nibec Co., Korea), and six synthetic bones, such as BMP (Couellmedi Co., Korea), BoneMedik (Meta Biomed Co., Korea), Bone plus (Megagen Co., Korea), MBCP (Biomatlante Co., France), Osteon (Genoss Co., Korea), and Osteogen (Impladent LTD., USA), were used. We used 1.0 and 2.0 MeV superconduction accelerator, and/or microtrone with different individual 60, 120 kGy irradiation dose. Different dose irradiated specimens were divided 6 portions each, so total 360 groups were prepared. 4 portions were analyzed each by elementary analysis using FE-SEM (Field Emission Scanning Microscopy) and another 2 portions were grafted to the calvarial defect of Sprague-Dawley rat, following histologic, immunohistochemical analysis and TEM study were processed at the 8th and 16th weeks, in vivo. This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST)

  2. OSTEOCALCIN DINAMIC OF DISTROPHICAL BONE KISTS BY TITANIUM NIKELID POROUS MATERIALS IMPLANTATION IN CHILDREN

    Directory of Open Access Journals (Sweden)

    I. I. Kuzhelivsky

    2015-01-01

    Full Text Available The article presents results of bone kists treatment by porous granular titanium nikelid materials and dynamic of osteokalcin. A comparative examination with standard treatment technology group demonstrated high efficiency of a proposed method. Porous granular titanium nikelid materials possess mechanical strength, optimization of regeneration at the expense of osteoinductivity by osteokalcin and allow you to effectively fill the cavity with a complex anatomical structure. 

  3. OSTEOCALCIN DINAMIC OF DISTROPHICAL BONE KISTS BY TITANIUM NIKELID POROUS MATERIALS IMPLANTATION IN CHILDREN

    OpenAIRE

    I. I. Kuzhelivsky; M. A. Akselrov; L. A. Sitko

    2015-01-01

    The article presents results of bone kists treatment by porous granular titanium nikelid materials and dynamic of osteokalcin. A comparative examination with standard treatment technology group demonstrated high efficiency of a proposed method. Porous granular titanium nikelid materials possess mechanical strength, optimization of regeneration at the expense of osteoinductivity by osteokalcin and allow you to effectively fill the cavity with a complex anatomical structure. 

  4. 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.

  5. Corrosion and alteration of materials from the nuclear industry; La Corrosion et l'alteration des materiaux du nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Feron, D.; Guerin, Y.; Latge, C.; Limoge, Y.; Madic, C.; Santarini, G.; Seiler, J.M.; Vernaz, E.; Richet, C.

    2010-07-01

    , testing means, experimental techniques, internal corrosion of zircaloy sheath - the iodine effect, stress corrosion of nickel alloys - hydrogen influence, stress corrosion of stainless steels; C - wear corrosion: a coupled phenomenon, research in the framework of service life extension of the French electronuclear park; 3 - Corrosion in future reactors: A - corrosion in gas reactors: corrosion by helium impurities, oxidation resistance of silicon carbide, corrosion of graphite and carbon-carbon composites; B - corrosion in liquid metal reactors: sodium FBRs, lead and lead alloys reactors; C- corrosion in molten salt reactors: corrosion of Hastelloy N-type nickel alloys by molten fluorides, mass transfer in aniso-thermal fluoride systems, tellurium embrittlement, electrochemical study of pure metals corrosion in molten fluorides; 4 - Materials corrosion and alteration in the back-end of the fuel cycle: A - corrosion in concentrated nitric environment: materials behaviour, self-catalytic mechanism of nitric acid reduction; B - corrosion in unsaturated aqueous environment: metallic corrosion in unsaturated environment - application to the storage of waste containers, bitumens alteration, reinforced concrete behaviour and iron framework corrosion, concrete behaviour in severe thermal environment; C - Corrosion in saturated aqueous environment: metals corrosion in clayey environment, long-term behaviour of glasses, ceramics alteration, underwater concrete durability, clays transformation; D - materials biodegradation: microorganisms and nuclear wastes, biodegradation of bitumen, concretes and steels; 5 - Conclusion, glossary

  6. [Preparation of sodium alginate-nanohydroxyapatite composite material for bone repair and its biocompatibility].

    Science.gov (United States)

    Wang, Yanmei; He, Jiacai; Li, Quanli; Shen, Jijia

    2014-02-01

    To prepare sodium alginate-nanohydroxyapatite composite material and to explore its feasibility as a bone repair material. Sodium alginate-nanohydroxyapatite composite material was prepared using chemical cross-linking and freeze-drying technology. The composite was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) and its porosity was measured by liquid displacement method. The fifth passage of bone marrow stromal stem cells (BMSCs) were incubated on the composite material and then growth was observed by inverted microscope and SEM. BMSCs were cultured with liquid extracts of the material, methyl thiazolyl tetrazolium (MTT) assay was used to calculate the relative growth rate (RGR) on 1, 3, 5 d and to evaluate the cytotoxicity. Fresh dog blood was added into the liquid extracts to conduct hemolysis test, the spectrophotometer was used to determine the optical density (OD) and to calculate the hemolysis rate. Sodium alginate-nanohydroxyapatite composite material displayed porosity, the porous pore rate was (88.6 +/- 4.5)%. BMSCs showed full stretching and vigorous growth under inverted microscope and SEM. BMSCs cultured with liquid extracts of the material had good activities. The toxicity of composite material was graded as 1. Hemolysis test results showed that the hemolysis rate of the composite material was 1.28%, thus meeting the requirement of medical biomaterials. The composite material fabricated in this study has high porosity and good biocompatibility.

  7. 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.

  8. Multislice quantitative computed tomography allows early detection of bone mineral density alterations induced by atherogenic diet in a growing rat experimental model

    International Nuclear Information System (INIS)

    Gubert, M.J.; Monforte, F.; Calo, C.; Lylyk, P.; Friedman, M.F.; Gamba, C.A.

    2012-01-01

    Purpose. To demonstrate the utility of Multislice Quantitative Computed Tomography (MS-QCT) in the early detection of mandibular bone mineral density (BMD) alterations induced by an atherogenic diet in a growing rat experimental model. Materials and Methods. Male weanling Wistar rats (n =16) were divided by body weight (Wt) into 2 groups: control (C) and experimental (E), with no significant differences in the mean initial Wt (p>0.05). C was fed rodent stock diet ad libitum, and E an atherogenic diet for 3 weeks (3w). Zoometry (body weight and length) and diet intake (g/100g rat/day) were monitored. At 3 w in serum (mg/dL) lipidlipoprotein profile was studied: total cholesterol (t-C), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), non-HDL cholesterol (non-HDL-C) and MSQCT (Philips 64 CT, quantified with the eFilm Workstation 2.1) in seven mandibular areas (MA): n. 1 to 4: from chin to mandibular foramen, n. 5: coronoid process, n. 6: condylar process, n. 7: angular process. Statistics: Pearson's correlation between BMD in each MA and serum t-C. p 0.05). Correlation coefficients (r) and their significance levels (p) were relevant in 5/7 MA. MA1:-0.580 (p=0.019), MA2:-0.709 (p=0.002), MA3:-0.635 (p=0.008), MA5:-0.674 (p=0.004), MA6:-0.564 (p=0.023). Conclusions. These results suggest that MS-QCT is an imaging diagnostic method that allows the early detection of mandible bone architecture alterations induced by an atherogenic diet. Inverse correlation between BMD and t-C would indicate an association between an atherogenic diet intake and potential temporomandibular disorders. (authors)

  9. 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

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    Tomasz Gredes

    2016-01-01

    Full Text Available 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.

  12. 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.

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

    International Nuclear Information System (INIS)

    Wydra, A; Maev, R Gr

    2013-01-01

    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. (note)

  14. Boron enhances strength and alters mineral composition of bone in rabbits fed a high energy diet.

    Science.gov (United States)

    Hakki, Sema S; Dundar, Niyazi; Kayis, Seyit Ali; Hakki, Erdogan E; Hamurcu, Mehmet; Kerimoglu, Ulku; Baspinar, Nuri; Basoglu, Abdullah; Nielsen, Forrest H

    2013-04-01

    An experiment was performed to determine whether boron had a beneficial effect on bone strength and composition in rabbits with apparent adiposity induced by a high energy diet. Sixty female New Zealand rabbits, aged 8 months, were randomly divided into five groups with the following treatments for seven months: control 1, fed alfalfa hay only (5.91 MJ/kg); control 2, high energy diet (11.76 MJ and 3.88 mg boron/kg); B10, high energy diet+10 mg/kg body weight boron gavage/96 h; B30, high energy diet+30 mg/kg body weight boron gavage/96 h; B50, high energy diet+50mg/kg body weight boron gavage/96 h. Bone boron concentrations were lowest in rabbits fed the high energy diet without boron supplementation, which suggested an inferior boron status. Femur maximum breaking force was highest in the B50 rabbits. Tibia compression strength was highest in B30 and B50 rabbits. All boron treatments significantly increased calcium and magnesium concentrations, and the B30 and B50 treatments increased the phosphorus concentration in tibia of rabbits fed the high energy diet. The B30 treatment significantly increased calcium, phosphorus and magnesium concentrations in femur of rabbits fed the high energy diet. Principal component analysis of the tibia minerals showed that the three boron treatments formed a separate cluster from controls. Discriminant analysis suggested that the concentrations of the minerals in femur could predict boron treatment. The findings indicate boron has beneficial effects on bone strength and mineral composition in rabbits fed a high energy diet. Copyright © 2012 Elsevier GmbH. All rights reserved.

  15. Optimization of Sample Preparation processes of Bone Material for Raman Spectroscopy.

    Science.gov (United States)

    Chikhani, Madelen; Wuhrer, Richard; Green, Hayley

    2018-03-30

    Raman spectroscopy has recently been investigated for use in the calculation of postmortem interval from skeletal material. The fluorescence generated by samples, which affects the interpretation of Raman data, is a major limitation. This study compares the effectiveness of two sample preparation techniques, chemical bleaching and scraping, in the reduction of fluorescence from bone samples during testing with Raman spectroscopy. Visual assessment of Raman spectra obtained at 1064 nm excitation following the preparation protocols indicates an overall reduction in fluorescence. Results demonstrate that scraping is more effective at resolving fluorescence than chemical bleaching. The scraping of skeletonized remains prior to Raman analysis is a less destructive method and allows for the preservation of a bone sample in a state closest to its original form, which is beneficial in forensic investigations. It is recommended that bone scraping supersedes chemical bleaching as the preferred method for sample preparation prior to Raman spectroscopy. © 2018 American Academy of Forensic Sciences.

  16. Marker for the pre-clinical development of bone substitute materials

    Directory of Open Access Journals (Sweden)

    de Wild Michael

    2017-09-01

    Full Text Available Thin mechanically stable Ti-cages have been developed for the in-vivo application as X-ray and histology markers for the optimized evaluation of pre-clinical performance of bone graft materials. A metallic frame defines the region of interest during histological investigations and supports the identification of the defect site. This standardization of the procedure enhances the quality of pre-clinical experiments. Different models of thin metallic frameworks were designed and produced out of titanium by additive manufacturing (Selective Laser Melting. The productibility, the mechanical stability, the handling and suitability of several frame geometries were tested during surgery in artificial and in ex-vivo bone before a series of cages was preclinically investigated in the female Göttingen minipigs model. With our novel approach, a flexible process was established that can be adapted to the requirements of any specific animal model and bone graft testing.

  17. 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.

  18. 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.

  19. Evaluation of Three Bone Substitute Materials in the Treatment of Experimentally Induced Defects in Rabbit Calvaria

    Directory of Open Access Journals (Sweden)

    M. Paknejad

    2007-12-01

    Full Text Available Objective: The aim of present study was to evaluate the quality, density and thickness of newly formed bone in experimental defects treated with Combi-Pack®, Bio-Oss® and Biostite®.Materials and Methods: Eight New Zealand white rabbits were included in this randomized,blinded study. Four equal 3×6 mm bone defects were created on the frontal and parietal bones of each animal and three were immediately grafted with Bio-Oss®, Combi-Pack® and Biostite® while one was left untreated, serving as negative control. Histologic and histomorphometric analysis was performed four weeks after surgery.Results: Histomorphometric bone area and trabecular maturity was significantly higher in the Bio-Oss® and Combi-Pack® samples as compared to the Biostite® and control cases.The amount of remaining biomaterial was almost equal in the three experimental groups at the end of the study period. Neither foreign body reaction nor severe inflammation was seen in any of the specimens except for the Biostite® samples.Conclusion: It may be suggested that implantation of Bio-Oss® particles and Combi-Pack® blocks can promote bone regeneration more effectively than Biostite®.

  20. Modulation of Host Osseointegration during Bone Regeneration by Controlling Exogenous Stem Cells Differentiation Using a Material Approach.

    Science.gov (United States)

    Yu, Xiaohua; Wang, Liping; Xia, Zengmin; Chen, Li; Jiang, Xi; Rowe, David; Wei, Mei

    2014-02-01

    Stem cell-based tissue engineering for large bone defect healing has attracted enormous attention in regenerative medicine. However, sufficient osseointegration of the grafts combined with exogenous stem cells still remains a major challenge. Here we developed a material approach to modulate the integration of the grafts to the host tissue when exogenous bone marrow stromal cells (BMSCs) were used as donor cells. Distinctive osseointegration of bone grafts was observed as we varied the content of hydroxyapatite (HA) in the tissue scaffolds implanted in a mouse femur model. More than 80% of new bone was formed in the first two weeks of implantation in high HA content scaffold but lack of host integration while only less than 5% of the new bone was formed during this time period in the no HA group but with much stronger host integration. Cell origin analysis leveraging GFP reporter indicates new bone in HA containing groups was mainly derived from donor BMSCs. In comparison, both host and donor cells were found on new bone surface in the no HA groups which led to seamless bridging between host tissue and the scaffold. Most importantly, host integration during bone formation is closely dictated to the content of HA present in the scaffolds. Taken together, we demonstrate a material approach to modulate the osseointegration of bone grafts in the context of exogenous stem cell-based bone healing strategy which might lead to fully functional bone tissue regeneration.

  1. Lead induces chondrogenesis and alters transforming growth factor-beta and bone morphogenetic protein signaling in mesenchymal cell populations.

    Science.gov (United States)

    Zuscik, Michael J; Ma, Lin; Buckley, Taylor; Puzas, J Edward; Drissi, Hicham; Schwarz, Edward M; O'Keefe, Regis J

    2007-09-01

    It has been established that skeletal growth is stunted in lead-exposed children. Because chondrogenesis is a seminal step during skeletal development, elucidating the impact of Pb on this process is the first step toward understanding the mechanism of Pb toxicity in the skeleton. The aim of this study was to test the hypothesis that Pb alters chondrogenic commitment of mesenchymal cells and to assess the effects of Pb on various signaling pathways. We assessed the influence of Pb on chondrogenesis in murine limb bud mesenchymal cells (MSCs) using nodule formation assays and gene analyses. The effects of Pb on transforming growth factor-beta (TGF-beta) and bone morphogenetic protein (BMP) signaling was studied using luciferase-based reporters and Western analyses, and luciferase-based assays were used to study cyclic adenosine monophosphate response element binding protein (CREB), beta-catenin, AP-1, and nuclear factor-kappa B (NF-kappaB) signaling. We also used an ectopic bone formation assay to determine how Pb affects chondrogenesis in vivo. Pb-exposed MSCs showed enhanced basal and TGF-beta/BMP induction of chondrogenesis, evidenced by enhanced nodule formation and up-regulation of Sox-9, type 2 collagen, and aggrecan, all key markers of chondrogenesis. We observed enhanced chondrogenesis during ectopic bone formation in mice preexposed to Pb via drinking water. In MSCs, Pb enhanced TGF-beta but inhibited BMP-2 signaling, as measured by luciferase reporter assays and Western analyses of Smad phosphorylation. Although Pb had no effect on basal CREB or Wnt/beta-catenin pathway activity, it induced NFkappaB signaling and inhibited AP-1 signaling. The in vitro and in vivo induction of chondrogenesis by Pb likely involves modulation and integration of multiple signaling pathways including TGF-beta, BMP, AP-1, and NFkappaB.

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

    Science.gov (United States)

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

    2017-12-01

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

  3. [Mastoid obliteration with a highly porous bone grafting material in combination with cartilage].

    Science.gov (United States)

    Punke, C; Goetz, W; Just, T; Pau, H-W

    2012-09-01

    An open mastoid cavity might lead to various problems for the patient. Chronic inflammation of the cavity with secretion, changes in the acoustic behavior, vertigo in restricted situations and an impaired self-cleaning function might affect the patient. For surgical treatment reducing of the size of such cavities have been described. Besides autologous materials such as hydroxyapatite or alloplastic substances as tricalcium phosphate have been previously used. A very slow resorption of these materials with rejection has been described. The new ceramic NanoBone® was fabricated in a sol-gel process at 700 °C depositing unsintered hydroxylapatite in a SiO2 structure. This method provides a nano/microstructure of high porosity of the resulting matrix. 20 patients were reexamined after an average of 2 years and 5 months after obliteration of the open mastoid cavity with NanoBone®. We compared pre- and postoperative findings in terms of otorrhea, frequency of medical consultation, vertigo and otoscopic findings. In 5 patients, in addition, a postoperative CT scan of the temporal bones was used for evaluation of osteoinduction and osteointegration. After obliteration of the open mastoid cavity with NanoBone ® we observed an uneventfully healing. After surgery we achieved a reduction of vertigo, otorrhea and frequency of medical consultations for the single patient. The obliteration of an open mastoid cavity with NanoBone ® is a safe alternative method relative to the surgical techniques with autologous materials. © Georg Thieme Verlag KG Stuttgart · New York.

  4. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Human Studies of Vertical and Horizontal Alveolar Ridge Augmentation Comparing Different Types of Bone Graft Materials: A Systematic Review.

    Science.gov (United States)

    Chavda, Suraj; Levin, Liran

    2018-02-01

    Alveolar ridge augmentation can be completed with various types of bone augmentation materials (autogenous, allograft, xenograft, and alloplast). Currently, autogenous bone is labeled as the "gold standard" because of faster healing times and integration between native and foreign bone. No systematic review has currently determined whether there is a difference in implant success between various bone augmentation materials. The purpose of this article was to systematically review comparative human studies of vertical and horizontal alveolar ridge augmentation comparing different types of bone graft materials (autogenous, allograft, xenograft, and alloplast). A MEDLINE search was conducted under the 3 search concepts of bone augmentation, dental implants, and alveolar ridge augmentation. Studies pertaining to socket grafts or sinus lifts were excluded. Case reports, small case series, and review papers were excluded. A bias assessment tool was applied to the final articles. Overall, 219 articles resulted from the initial search, and 9 articles were included for final analysis. There were no discernible differences in implant success between bone augmentation materials. Generally, patients preferred nonautogenous bone sources as there were fewer hospital days, less pain, and better recovery time. Two articles had industrial support; however, conclusions of whether that support influenced the outcomes could not be determined. Future comparative studies should compare nonautogenous bone sources and have longer follow-up times.

  6. 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.

  7. Micromechanical modeling of the cement-bone interface: the effect of friction, morphology and material properties on the micromechanical response

    OpenAIRE

    Janssen, Dennis; Mann, Kenneth A.; Verdonschot, Nico

    2008-01-01

    In order to gain insight into the micro-mechanical behavior of the cement-bone interface, the effect of parametric variations of frictional, morphological and material properties on the mechanical response of the cement-bone interface were analyzed using a finite element approach. Finite element models of a cement-bone interface specimen were created from micro-computed tomography data of a physical specimen that was sectioned from an in vitro cemented total hip arthroplasty. In five models t...

  8. Study of the toughening mechanisms in bone and biomimetic hydroxyapatite materials using Raman microprobe spectroscopy.

    Science.gov (United States)

    Pezzotti, Giuseppe; Sakakura, Seiji

    2003-05-01

    A Raman microprobe spectroscopy characterization of microscopic fracture mechanisms is presented for a natural hydroxyapatite material (cortical bovine femur) and two synthetic hydroxyapatite-based materials with biomimetic structures-a hydroxyapatite skeleton interpenetrated with a metallic (silver) or a polymeric (nylon-6) phase. In both the natural and synthetic materials, a conspicuous amount of toughening arose from a microscopic crack-bridging mechanism operated by elasto-plastic stretching of unbroken second-phase ligaments along the crack wake. This mechanism led to a rising R-curve behavior. An additional micromechanism, responsible for stress relaxation at the crack tip, was recognized in the natural bone material and was partly mimicked in the hydroxyapatite/silver composite. This crack-tip mechanism conspicuously enhanced the cortical bone material resistance to fracture initiation. A piezo-spectroscopic technique, based on a microprobe measurement of 980 cm(-1) Raman line of hydroxyapatite, enabled us to quantitatively assess in situ the microscopic stress fields developed during fracture both at the crack tip and along the crack wake. Using the Raman piezo-spectroscopy technique, toughening mechanisms were assessed quantitatively and rationally related to the macroscopic fracture characteristics of hydroxyapatite-based materials. Copyright 2003 Wiley Periodicals, Inc.

  9. 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.

  10. 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.

  11. A numerical study on stress distribution across the ankle joint: Effects of material distribution of bone, muscle force and ligaments.

    Science.gov (United States)

    Mondal, Subrata; Ghosh, Rajesh

    2017-09-01

    The goal of this study is to develop a realistic three dimensional FE model of intact ankle joint. Three dimensional FE model of the intact ankle joint was developed using computed tomography data sets. The effect of muscle force, ligaments and proper material property distribution of bone on stress distribution across the intact ankle joint was studied separately. Present study indicates bone material property, ligaments and muscle force have influence on stress distribution across the ankle joint. Proper bone material, ligaments and muscle must be considered in the computational model for pre-clinical analysis of ankle prosthesis.

  12. 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...

  13. Itataia ore deposit - Caracterization of the massif according alteration/argilization and estimation of material volume inside a pit

    International Nuclear Information System (INIS)

    Alcantara e Silva, J.R. de.

    1986-01-01

    This paper sumarizes the geotechnically characterization of the Itataia ore deposit according to the relationship rock alteration/argilization. Through this charaterization it was defined three types of material related to the degree of alteration and argillization: Type I (fresh or pratically fresh and little or monargillized material); Type II (partially altered and argillized material). The new geological syntesis and iformation, together with seismic parameters allowed to a material classification according to the scarificability, and important factor in the costs of an open pit mine. (author) [pt

  14. 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.

  15. Estrogen depletion and drug treatment alter the microstructure of type I collagen in bone

    Directory of Open Access Journals (Sweden)

    Meagan A. Cauble

    2016-12-01

    Full Text Available The impact of estrogen depletion and drug treatment on type I collagen fibril nanomorphology and collagen fibril packing (microstructure was evaluated by atomic force microscopy (AFM using an ovariectomized (OVX rabbit model of estrogen deficiency induced bone loss. Nine month-old New Zealand white female rabbits were treated as follows: sham-operated (Sham; n = 11, OVX + vehicle (OVX + Veh; n = 12, OVX + alendronate (ALN, 600 μg/kg/wk., s.c.; n = 12, and OVX + cathepsin-K inhibitor L-235 (CatKI, 10 mg/kg, daily, p.o.; n = 13 in prevention mode for 27 weeks. Samples from the cortical femur and trabecular lumbar vertebrae were polished, demineralized, and imaged using AFM. Auto-correlation of image patches was used to generate a vector field for each image that mathematically approximated the collagen fibril alignment. This vector field was used to compute an information-theoretic entropy that was employed as a quantitative fibril alignment parameter (FAP to allow image-to-image and sample-to-sample comparison. For all samples, no change was observed in the average FAP values; however significant differences in the distribution of FAP values were observed. In particular, OVX + Veh lumbar vertebrae samples contained a tail of lower FAP values representing regions of greater fibril alignment. OVX + ALN treatment resulted in a FAP distribution with a tail indicating greater alignment for cortical femur and less alignment for trabecular lumbar vertebrae. OVX + CatKI treatment gave a distribution of FAP values with a tail indicating less alignment for cortical femur and no change for trabecular lumbar vertebrae. Fibril alignment was also evaluated by considering when a fibril was part of discrete bundles or sheets (classified as parallel or not (classified as oblique. For this analysis, the percentage of parallel fibrils in cortical femur for the OVX group was 17% lower than the Sham group. OVX + ALN treatment partially

  16. A well-balanced diet combined or not with exercise induces fat mass loss without any decrease of bone mass despite bone micro-architecture alterations in obese rat.

    Science.gov (United States)

    Gerbaix, Maude; Metz, Lore; Mac-Way, Fabrice; Lavet, Cédric; Guillet, Christelle; Walrand, Stéphane; Masgrau, Aurélie; Vico, Laurence; Courteix, Daniel

    2013-04-01

    The association of a well-balanced diet with exercise is a key strategy to treat obesity. However, weight loss is linked to an accelerated bone loss. Furthermore, exercise is known to induce beneficial effects on bone. We investigated the impact of a well-balanced isoenergetic reducing diet (WBR) and exercise on bone tissue in obese rats. Sixty male rats had previously been fed with a high fat/high sucrose diet (HF/HS) for 4months to induce obesity. Then, 4 regimens were initiated for 2months: HF/HS diet plus exercise (treadmill: 50min/day, 5days/week), WBR diet plus exercise, HF/HS diet plus inactivity and WBR diet plus inactivity. Body composition and total BMD were assessed using DXA and visceral fat mass was weighed. Tibia densitometry was assessed by Piximus. Bone histomorphometry was performed on the proximal metaphysis of tibia and on L2 vertebrae (L2). Trabecular micro-architectural parameters were measured on tibia and L2 by 3D microtomography. Plasma concentration of osteocalcin and CTX were measured. Both WBR diet and exercise had decreased global weight, global fat and visceral fat mass (pdiet alone failed to alter total and tibia bone mass and BMD. However, Tb.Th, bone volume density and degree of anisotropy of tibia were decreased by the WBR diet (pdiet had involved a significant lower MS/BS and BFR/BS in L2 (pdiet inducing weight and fat mass losses did not affected bone mass and BMD of obese rats despite alterations of their bone micro-architecture. The moderate intensity exercise performed had improved the tibia BMD of obese rats without any trabecular and cortical adaptation. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Promoted new bone formation in maxillary distraction osteogenesis using a tissue-engineered osteogenic material.

    Science.gov (United States)

    Kinoshita, Kazuhiko; Hibi, Hideharu; Yamada, Yoichi; Ueda, Minoru

    2008-01-01

    Bilateral maxillary distraction was performed at a higher rate in rabbits to determine whether locally applied tissue-engineered osteogenic material (TEOM) enhances bone regeneration. The material was an injectable gel composed of autologous mesenchymal stem cells, which were cultured then induced to be osteogenic in character, and platelet-rich plasma (PRP). After a 5-day latency period, distraction devices were activated at a rate of 2.0 mm once daily for 4 days. Twelve rabbits were divided into 2 groups. At the end of distraction, the experimental group of rabbits received an injection of TEOM into the distracted tissue on one side, whereas, saline solution was injected into the distracted tissue on the contralateral side as the internal control. An additional control group received an injection of PRP or saline solution into the distracted tissue in the same way as the experimental group. The distraction regenerates were assessed by radiological and histomorphometric analyses. The radiodensity of the distraction gap injected with TEOM was significantly higher than that injected with PRP or saline solution at 2, 3, and 4 weeks postdistraction. The histomorphometric analysis also showed that both new bone zone and bony content in the distraction gap injected with TEOM were significantly increased when compared with PRP or saline solution. Our results demonstrated that the distraction gap injected with TEOM showed significant new bone formation. Therefore, injections of TEOM may be able to compensate for insufficient distraction gaps.

  18. Mechanical, material, and antimicrobial properties of acrylic bone cement impregnated with silver nanoparticles.

    Science.gov (United States)

    Slane, Josh; Vivanco, Juan; Rose, Warren; Ploeg, Heidi-Lynn; Squire, Matthew

    2015-03-01

    Prosthetic joint infection is one of the most serious complications that can lead to failure of a total joint replacement. Recently, the rise of multidrug resistant bacteria has substantially reduced the efficacy of antibiotics that are typically incorporated into acrylic bone cement. Silver nanoparticles (AgNPs) are an attractive alternative to traditional antibiotics resulting from their broad-spectrum antimicrobial activity and low bacterial resistance. The purpose of this study, therefore, was to incorporate metallic silver nanoparticles into acrylic bone cement and quantify the effects on the cement's mechanical, material and antimicrobial properties. AgNPs at three loading ratios (0.25, 0.5, and 1.0% wt/wt) were incorporated into a commercial bone cement using a probe sonication technique. The resulting cements demonstrated mechanical and material properties that were not substantially different from the standard cement. Testing against Staphylococcus aureus and Staphylococcus epidermidis using Kirby-Bauer and time-kill assays demonstrated no antimicrobial activity against planktonic bacteria. In contrast, cements modified with AgNPs significantly reduced biofilm formation on the surface of the cement. These results indicate that AgNP-loaded cement is of high potential for use in primary arthroplasty where prevention of bacterial surface colonization is vital. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. The effect of distal ulnar implant stem material and length on bone strains.

    Science.gov (United States)

    Austman, Rebecca L; Beaton, Brendon J B; Quenneville, Cheryl E; King, Graham J W; Gordon, Karen D; Dunning, Cynthia E

    2007-01-01

    Implant design parameters can greatly affect load transfer from the implant stem to the bone. We have investigated the effect of length or material of distal ulnar implant stems on the surrounding bone strains. Eight cadaveric ulnas were instrumented with 12 strain gauges and secured in a customized jig. Strain data were collected while loads (5-30 N) were applied to the medial surface of the native ulnar head. The native ulnar head was removed, and a stainless steel implant with an 8-cm-long finely threaded stem was cemented into the canal. After the cement had cured, the 8-cm stem was removed, leaving a threaded cement mantle in the canal that could accept shorter threaded stems of interest. The loading protocol was then repeated for stainless steel stems that were 7, 5, and 3 cm in length, as well as for a 5-cm-long titanium alloy (TiAl(6)V(4)) stem. Other stainless steel stem lengths between 3 and 7 cm were tested at intervals of 0.5 cm, with only a 20 N load applied. No stem length tested matched the native strains at all gauge locations. No significant differences were found between any stem length and the native bone at the 5th and 6th strain gauge positions. Strains were consistently closer to the native bone strains with the titanium stem than the stainless steel stem for each gauge pair that was positioned on the bone overlying the stem. The 3-cm stem results were closer to the native strains than the 7-cm stem for all loads at gauges locations that were on top of the stem. The results from this study suggest that the optimal stem characteristics for distal ulnar implants from a load transfer point of view are possessed by shorter (approximately 3 to 4 cm) titanium stems.

  20. Alteration of cancer pain-related signals by radiation: Proteomic analysis in an animal model with cancer bone invasion

    International Nuclear Information System (INIS)

    Park, Hee Chul; Seong, Jinsil; An, Jung Hee; Kim, Jiyoung; Kim, Un Jung; Lee, Bae Whan

    2005-01-01

    Purpose: Although radiotherapy is highly effective in relieving bone pain due to cancer invasion, its mechanism remains unclear. The aim of this study was to explore this mechanism in an animal model system. Methods and Materials: A hind paw model of cancer pain was developed by transplanting a murine hepatocarcinoma, HCa-1, into the periosteal membrane of the foot dorsum of C3H/HeJ mice. Bone invasion from HCa-1 was histopathologically confirmed from sequential tumor sampling. For three experimental groups, a control (N), tumor without radiation (T), and tumor with radiation (TR), the development and level of pain were objectively examined in mice with a growing tumor by assessing pain-associated behavior. The differential expression of pain-related signals in the spinal cord was analyzed by proteomic analysis using high-resolution two-dimensional gel electrophoresis (2-DE) and mass spectrometry, and those of proteins by Western blotting. The pain-mediating neurotransmitters in the spinal cord were also examined by immunohistochemical staining for calcitonin gene-related peptide (CGRP) and substance P. Results: In the histopathologic examinations, bone invasion from HCa-1 was seen from Day 7 and was evident at Day 14 after transplantation, and measurable pain-associated behaviors were developed from Day 7. After 25 Gy of radiation to the tumors, the objective level of pain in the TR group decreased, with higher thresholds to mechanical and thermal stimulation than in the T group. From the 2-DE of spinal cord, 107 spots were identified; 12 proteins were changed more than fivefold because of tumor formation but then reversed after radiation in the tumor-bearing mice. The proteins involved included secretagogin, syntenin, P2X purinoreceptor 6 (P2X6), and Ca 2+ /Calmodulin-dependent protein kinase 1 (CaM kinase 1), the functions of which have been known to be involved in the Ca 2+ -signaling cascade, ATP-mediated fast synaptic transmission, or control of vesicular

  1. Alteration of cancer pain-related signals by radiation: Proteomic analysis in an animal model with cancer bone invasion

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hee Chul [Department of Radiation Oncology, Hallym University, Chuncheon (Korea, Republic of); Seong, Jinsil [Department of Radiation Oncology, Brain Korea 21 Project for Medicine, Yonsei University, Seoul (Korea, Republic of); An, Jung Hee [Department of Radiation Oncology, Brain Korea 21 Project for Medicine, Yonsei University, Seoul (Korea, Republic of); Kim, Jiyoung [Department of Radiation Oncology, Brain Korea 21 Project for Medicine, Yonsei University, Seoul (Korea, Republic of); Kim, Un Jung [Yonsei Medical Research Center, Brain Korea 21 Project for Medicine, Yonsei University, Seoul (Korea, Republic of); Lee, Bae Whan [Yonsei Medical Research Center, Brain Korea 21 Project for Medicine, Yonsei University, Seoul (Korea, Republic of)

    2005-04-01

    Purpose: Although radiotherapy is highly effective in relieving bone pain due to cancer invasion, its mechanism remains unclear. The aim of this study was to explore this mechanism in an animal model system. Methods and Materials: A hind paw model of cancer pain was developed by transplanting a murine hepatocarcinoma, HCa-1, into the periosteal membrane of the foot dorsum of C3H/HeJ mice. Bone invasion from HCa-1 was histopathologically confirmed from sequential tumor sampling. For three experimental groups, a control (N), tumor without radiation (T), and tumor with radiation (TR), the development and level of pain were objectively examined in mice with a growing tumor by assessing pain-associated behavior. The differential expression of pain-related signals in the spinal cord was analyzed by proteomic analysis using high-resolution two-dimensional gel electrophoresis (2-DE) and mass spectrometry, and those of proteins by Western blotting. The pain-mediating neurotransmitters in the spinal cord were also examined by immunohistochemical staining for calcitonin gene-related peptide (CGRP) and substance P. Results: In the histopathologic examinations, bone invasion from HCa-1 was seen from Day 7 and was evident at Day 14 after transplantation, and measurable pain-associated behaviors were developed from Day 7. After 25 Gy of radiation to the tumors, the objective level of pain in the TR group decreased, with higher thresholds to mechanical and thermal stimulation than in the T group. From the 2-DE of spinal cord, 107 spots were identified; 12 proteins were changed more than fivefold because of tumor formation but then reversed after radiation in the tumor-bearing mice. The proteins involved included secretagogin, syntenin, P2X purinoreceptor 6 (P2X6), and Ca{sup 2+}/Calmodulin-dependent protein kinase 1 (CaM kinase 1), the functions of which have been known to be involved in the Ca{sup 2+}-signaling cascade, ATP-mediated fast synaptic transmission, or control of

  2. The Development of Biomimetic Spherical Hydroxyapatite/Polyamide 66 Biocomposites as Bone Repair Materials

    Directory of Open Access Journals (Sweden)

    Xuesong Zhang

    2014-01-01

    Full Text Available A novel biomedical material composed of spherical hydroxyapatite (s-HA and polyamide 66 (PA biocomposite (s-HA/PA was prepared, and its composition, mechanical properties, and cytocompatibility were characterized and evaluated. The results showed that HA distributed uniformly in the s-HA/PA matrix. Strong molecule interactions and chemical bonds were presented between the s-HA and PA in the composites confirmed by IR and XRD. The composite had excellent compressive strength in the range between 95 and 132 MPa, close to that of natural bone. In vitro experiments showed the s-HA/PA composite could improve cell growth, proliferation, and differentiation. Therefore, the developed s-HA/PA composites in this study might be used for tissue engineering and bone repair.

  3. Application of Glow Discharge Plasma to Alter Surface Properties of Materials

    Science.gov (United States)

    Trigwell, Steve; Buhler, Charles R.; Calle, Carlos I.

    2005-01-01

    Some polymer materials that are considered important for spaceport operations are rendered noncompliant when subjected to the Kennedy Space Center (KSC) Standard electrostatic testing. These materials operate in stringent environmental conditions, such as high humidity. Treating materials that fail electrostatic testing and altering their surface properties so that they become compliant would result in considerable cost savings. Significant improvement in electrostatic dissipation of Saf-T-Vu PVC after treatment with air Atmospheric Plasma Glow Discharge (APGD) was observed and the material now passed the KSC electrostatic test. The O:C ratio on the surface, as monitored by X-ray Photoelectron Spectroscopy, increased from 0.165 tO 0.275 indicating enhanced oxidation, and surface contact angle measurements decreased from 107.5 to 72.6 showing increased hydrophilicity that accounted for the increased conductivity. Monitoring of the aging showed that the materials hydrophobic recovery resulted in it failing the electrostatic test 30 hours after treatment. This was probably due to the out-diffusion of the added Zn, Ba, and Cd salt stabilizers detected on the surface and/or diffusion of low molecular weight oligomers. On going work includes improving the long term hydrophilicity by optimizing the APGD process with different gas mixtures. Treatment of other spaceport materials is also presented.

  4. A Phex mutation in a murine model of X-linked hypophosphatemia alters phosphate responsiveness of bone cells.

    Science.gov (United States)

    Ichikawa, Shoji; Austin, Anthony M; Gray, Amie K; Econs, Michael J

    2012-02-01

    Mutations in the PHEX gene cause X-linked hypophosphatemia (XLH). Hypophosphatemia in XLH results from increased circulating levels of a phosphaturic hormone, fibroblast growth factor 23 (FGF23), which inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D (calcitriol) synthesis. The current standard therapy for XLH--high-dose phosphate and calcitriol--further increases FGF23 concentrations, suggesting that patients with XLH may have an altered response to extracellular phosphate. To test for the presence of abnormal phosphate responsiveness, we compared serum biochemistries and femoral Fgf23 mRNA expression between wild-type mice, murine models of XLH (Phex(K496X)) and hyperphosphatemic tumoral calcinosis (Galnt3(-/-)), and Galnt3/Phex double-mutant mice. Phex mutant mice had not only increased Fgf23 expression but also reduced proteolytic cleavage of intact Fgf23 protein, resulting in markedly elevated intact Fgf23 levels and consequent hypophosphatemia. In contrast, despite markedly increased Fgf23 expression, Galnt3 knockout mice had significantly high proteolytic cleavage of Fgf23 protein, leading to low intact Fgf23 concentrations and hyperphosphatemia. Galnt3/Phex double-mutant mice had an intermediate biochemical phenotype between wild-type and Phex mutant mice, including slightly elevated intact Fgf23 concentrations with milder hypophosphatemia. Despite the hypophosphatemia, double-mutant mice attempted to reduce serum phosphate back to the level of Phex mutant mice by upregulating Fgf23 expression as much as 24-fold higher than Phex mutant mice. These data suggest that Phex mutations alter the responsiveness of bone cells to extracellular phosphate concentrations and may create a lower set point for "normal" phosphate levels.

  5. Immobilization and long-term recovery results in large changes in bone structure and strength but no corresponding alterations of osteocyte lacunar properties.

    Science.gov (United States)

    Bach-Gansmo, Fiona Linnea; Wittig, Nina Kølln; Brüel, Annemarie; Thomsen, Jesper Skovhus; Birkedal, Henrik

    2016-10-01

    The ability of osteocytes to demineralize the perilacunar matrix, osteocytic osteolysis, and thereby participate directly in bone metabolism, is an aspect of osteocyte biology that has received increasing attention during the last couple of years. The aim of the present work was to investigate whether osteocyte lacunar properties change during immobilization and subsequent recovery. A rat cortical bone model with negligible Haversian remodeling effects was used, with temporary immobilization of one hindlimb induced by botulinum toxin. Several complementary techniques covering multiple length scales enabled correlation of osteocyte lacunar properties to changes observed on the organ and tissue level of femoral bone. Bone structural parameters measured by μCT and mechanical properties were compared to sub-micrometer resolution SR μCT data mapping an unprecedented number (1.85 million) of osteocyte lacunae. Immobilization induced a significant reduction in aBMD, bone volume, tissue volume, and load to fracture, as well as the muscle mass of rectus femoris. During the subsequent recovery period, the bone structural and mechanical properties were only partly regained in spite of a long-term (28weeks) study period. No significant changes in osteocyte lacunar volume, density, oblateness, stretch, or orientation were detected upon immobilization or subsequent recovery. In conclusion, the bone architecture and not osteocyte lacunar properties or bone material characteristics dominate the immobilization response as well as the subsequent recovery. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Injectable calcium sulfate/mineralized collagen-based bone repair materials with regulable self-setting properties.

    Science.gov (United States)

    Chen, Zonggang; Liu, Huanye; Liu, Xi; Cui, Fu-Zhai

    2011-12-15

    An injectable and self-setting bone repair materials (nano-hydroxyapatite/collagen/calcium sulfate hemihydrate, nHAC/CSH) was developed in this study. The nano-hydroxyapatite/collagen (nHAC) composite, which is the mineralized fibril by self-assembly of nano-hydrocyapatite and collagen, has the same features as natural bone in both main hierarchical microstructure and composition. It is a bioactive osteoconductor due to its high level of biocompatibility and appropriate degradation rate. However, this material lacks handling characteristics because of its particle or solid-preformed block shape. Herein, calcium sulfate hemihydrate (CSH) was introduced into nHAC to prepare an injectable and self-setting in situ bone repair materials. The morphology of materials was observed using SEM. Most important and interesting of all, calcium sulfate dihydrate (CSD), which is not only the reactant of preparing CSH but also the final solidified product of CSH, was introduced into nHAC as setting accelerator to regulate self-setting properties of injectable nHAC/CSH composite, and thus the self-setting time of nHAC/CSH composite can be regulated from more than 100 min to about 30 min and even less than 20 min by adding various amount of setting accelerator. The compressive properties of bone graft substitute after final setting are similar to those of cancellous bone. CSD as an excellent setting accelerator has no significant effect on the mechanical property and degradability of bone repair materials. In vitro biocompatibility and in vivo histology studies demonstrated that the nHAC/CSH composite could provide more adequate stimulus for cell adhesion and proliferation, embodying favorable cell biocompatibility and a strong ability to accelerate bone formation. It can offer a satisfactory biological environment for growing new bone in the implants and for stimulating bone formation. Copyright © 2011 Wiley Periodicals, Inc.

  7. 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

  8. The influence of different loads on the remodeling process of a bone and bioresorbable material mixture with voids

    Science.gov (United States)

    Giorgio, Ivan; Andreaus, Ugo; Madeo, Angela

    2016-03-01

    A model of a mixture of bone tissue and bioresorbable material with voids was used to numerically analyze the physiological balance between the processes of bone growth and resorption and artificial material resorption in a plate-like sample. The adopted model was derived from a theory for the behavior of porous solids in which the matrix material is linearly elastic and the interstices are void of material. The specimen—constituted by a region of bone living tissue and one of bioresorbable material—was acted by different in-plane loading conditions, namely pure bending and shear. Ranges of load magnitudes were identified within which physiological states become possible. Furthermore, the consequences of applying different loading conditions are examined at the end of the remodeling process. In particular, maximum value of bone and material mass densities, and extensions of the zones where bone is reconstructed were identified and compared in the two different load conditions. From the practical view point, during surgery planning and later rehabilitation, some choice of the following parameters is given: porosity of the graft, material characteristics of the graft, and adjustment of initial mixture tissue/bioresorbable material and later, during healing and remodeling, optimal loading conditions.

  9. Sterilisation of allograft cortical bone using gamma irradiation: effect on strength and material ultrastructure

    International Nuclear Information System (INIS)

    Price, R.; Walters, M.

    1996-01-01

    Full text: The use of allograft bone in revision joint and limb salvage surgery is widespread and increasing (Buck B.E. et al, Clin Orthop 303: 8-17, 1994). To reduce the risk of disease transmission from donor graft contamination (particularly HIV and hepatitis) sterilisation is practiced worldwide. Gamma (γ)-irradiation using a dose of 1.5 - 2.5 Mrads is common. However, γ-irradiation is known to reduce bone strength, though the extent and mechanisms are controversial (eg Bright RW et al, Trans Orthop Res Soc 3: 210, 1978). We measured the effect of γ-irradiation on bone strength and properties reflecting bone material ultrastructure. Diaphyseal bone was obtained from the femur of a 47 year-old male would-be donor with suspicious hepatitis serology. Beams of cortical bone (long axes parallel to the femur) were cut using a low speed diamond saw bathed in Ringer's solution. Four groups were irradiated with γ-rays (0, 1.5, 2.5 and 5.0±0.5[SD] Mrads). Blinded investigations were performed: Ultimate stress (Ult Stress, N= 16 replicates in each dose group). Each beam was loaded at its midpoint at a rate of 25 mm/min until failure, while its ends were supported 40 mms apart. Ult stress was calculated from 3-point bending theory using the load vs displacement curve and the cross-sectional area of the break (Power RA et al, submitted to J Bone and Joint Surg). Differential scanning calorimetry (DSC) was performed over the range -15 to +5 deg C. Samples were demineralized and small (7-10 mg) blocks were cut and sealed in stainless steel calorimetry capsules. The enthalpy (reflecting the normalised free water content) was calculated from the sample mass plus area under the heat capacity curve. Pyridinoline collagen (acid-insoluble) crosslinks (Pyrid, N=10) (Randall D et al, JBone and Min Res, 1996, in press) were determined from 5-mm 3 demineralised, freeze dried samples. Small and medium angle X-ray diffraction (XRD, N=5). Demineralised bone was sliced into thin

  10. Effect of the Interposition of Calcium Phosphate Materials on Tendon-Bone Healing During Repair of Chronic Rotator Cuff Tear.

    Science.gov (United States)

    Zhao, Song; Peng, Lingjie; Xie, Guoming; Li, Dingfeng; Zhao, Jinzhong; Ning, Congqin

    2014-08-01

    The current nature of tendon-bone healing after rotator cuff (RC) repair is still the formation of granulation tissue at the tendon-bone interface rather than the formation of fibrocartilage, which is the crucial structure in native tendon insertion and can be observed after knee ligament reconstruction. The interposition of calcium phosphate materials has been found to be able to enhance tendon-bone healing in knee ligament reconstruction. However, whether the interposition of these kinds of materials can enhance tendon-bone healing or even change the current nature of tendon-bone healing after RC repair still needs to be explored. The interposition of calcium phosphate materials during RC repair would enhance tendon-bone healing or change its current nature of granulation tissue formation into a more favorable process. Controlled laboratory study. A total of 144 male Sprague-Dawley rats underwent unilateral detachment of the supraspinatus tendon, followed by delayed repair after 3 weeks. The animals were allocated into 1 of 3 groups: (1) repair alone, (2) repair with Ca5(PO4)2SiO4 (CPS) bioceramic interposition, or (3) repair with hydroxyapatite (HA) bioceramic interposition at the tendon-bone interface. Animals were sacrificed at 2, 4, or 8 weeks postoperatively, and microcomputed tomography (micro-CT) was used to quantify the new bone formation at the repair site. New fibrocartilage formation and collagen organization at the tendon-bone interface was evaluated by histomorphometric analysis. Biomechanical testing of the supraspinatus tendon-bone complex was performed. Statistical analysis was performed using 1-way analysis of variance. Significance was set at P repair, CPS bioceramic significantly increased the area of fibrocartilage at the tendon-bone interface compared with the control and HA groups. Moreover, CPS and HA bioceramics had significantly improved collagen organization. Biomechanical tests indicated that the CPS and HA groups have greater ultimate

  11. 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.

  12. The effect of nitrates on the alteration of the cementitious material

    International Nuclear Information System (INIS)

    Takei, Akihiko; Owada, Hitoshi; Fujita, Hideki; Negishi, Kumi

    2002-02-01

    TRU waste includes various chemical compounds such as nitrates. The influence of the chemical compounds on the performance of the barrier system should be estimated. Since the temperature of the deep-underground is higher than that of the near surface and a part of the TRU waste generates the heat accompanied with the decay of the radioactive nuclides, the influences of the heat to the barrier material also should be taken into account. In this study, we estimated the influence of sodium nitrate and also that of the leachate from the ROBE-waste (borate-solidified body of concentrated low-level waste) to the degradation of the cementitious material. We also obtained the mineralogical data of cementitious mineral after alteration in elevated temperature conditions. Results in this year are described below. 1) Alteration of characteristics of cementitious material in nitrate solution were evaluated by the water permeation test using sodium nitrate solution. The enhancement of the alteration of cementitious material due to sodium nitrate was observed. The dissolution quantity of the calcium of sodium nitrate solution permeated sample was larger than that of deionized water permeated sample (denoted as 'blank' in following). Hydraulic conductivity of sodium nitrate solution permeated sample was lower than blank, but after changing permeation liquid from sodium nitrate solution to deionized water, hydraulic conductivity rose quickly. The increase of porosity and the decrease of compressive strength were observed in the case of sodium nitrate solution compared with blank. In the nitrate solution, sulfate type and carbonate type of AFm changed into the nitrate type AFm. The nitrate type AFm altered to the carbonate type AFm when the nitrate concentration was lowered. 2) The influence of the leachate from the two types of ROBE-waste on the dissolution of the cementitious material was evaluated by the leaching experiments. Dissolution of the calcium from the cementitious

  13. Bone cell-material interactions on metal-ion doped polarized hydroxyapatite

    International Nuclear Information System (INIS)

    Bodhak, Subhadip; Bose, Susmita; Bandyopadhyay, Amit

    2011-01-01

    The objective of this work is to study the influence of Mg 2+ and Sr 2+ dopants on in vitro bone cell-material interactions of electrically polarized hydroxyapatite [HAp, Ca 10 (PO 4 ) 6 (OH) 2 ] ceramics with an aim to achieve additional advantage of matching bone chemistry along with the original benefits of electrical polarization treatment relevant to biomedical applications. To achieve our research objective, commercial phase pure HAp has been doped with MgO, and SrO in single, and binary compositions. All samples have been sintered at 1200 deg. C for 2 h and subsequently polarized using an external d.c. field (2.0 kV/cm) at 400 deg. C for 1 h. Combined addition of 1 wt.% MgO/1 wt.% SrO in HAp has been most beneficial in enhancing the polarizability in which stored charge was 4.19 μC/cm 2 compared to pure HAp of 2.23 μC/cm 2 . Bone cell-material interaction has been studied by culturing with human fetal osteoblast cells (hFOB) for a maximum of 7 days. Scanning electron microscope (SEM) images of cell morphology reveal that favorable surface properties and dopant chemistry lead to good cellular adherence and spreading on negatively charged surfaces of both Sr 2+ and Mg 2+ doped HAp samples over undoped HAp. MTT assay results at 7 days show the highest viable cell densities on the negatively charged surfaces of binary doped HAp samples, while positive charged doped HAp surfaces exhibit limited cellular growth in comparison to neutral surfaces.

  14. Bone substitute material composition and morphology differentially modulate calcium and phosphate release through osteoclast-like cells.

    Science.gov (United States)

    Konermann, A; Staubwasser, M; Dirk, C; Keilig, L; Bourauel, C; Götz, W; Jäger, A; Reichert, C

    2014-04-01

    The aim of this study was to determine the material composition and cell-mediated remodelling of different calcium phosphate-based bone substitutes. Osteoclasts were cultivated on bone substitutes (Cerabone, Maxresorb, and NanoBone) for up to 5 days. Bafilomycin A1 addition served as the control. To determine cellular activity, the supernatant content of calcium and phosphate was measured by inductively coupled plasma optical emission spectrometry. Cells were visualized on the materials by scanning electron microscopy. Material composition and surface characteristics were assessed by energy-dispersive X-ray spectroscopy. Osteoclast-induced calcium and phosphate release was material-specific. Maxresorb exhibited the highest ion release to the medium (P = 0.034; calcium 40.25mg/l day 5, phosphate 102.08 mg/l day 5) and NanoBone the lowest (P = 0.021; calcium 8.43 mg/l day 5, phosphate 15.15 mg/l day 5); Cerabone was intermediate (P = 0.034; calcium 16.34 mg/l day 5, phosphate 30.6 mg/l day 5). All investigated materials showed unique resorption behaviours. The presented methodology provides a new perspective on the investigation of bone substitute biodegradation, maintaining the material-specific micro- and macrostructure. Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  15. Modelling of Cortical Bone Tissue as a Fluid Saturated Double-Porous Material - Parametric Study

    Directory of Open Access Journals (Sweden)

    Jana TURJANICOVÁ

    2013-06-01

    Full Text Available In this paper, the cortical bone tissue is considered as a poroelastic material with periodic structure represented at microscopic and mesoscopic levels. The pores of microscopic scale are connected with the pores of mesoscopic scale creating one system of connected network filled with compressible fluid. The method of asymptotic homogenization is applied to upscale the microscopic model of the fluid-solid interaction under a static loading. Obtained homogenized coefficients describe material properties of the poroelastic matrix fractured by fluid-filled pores whose geometry is described at the mesoscopic level. The second-level upscaling provides homogenized poroelastic coefficients relevant on the macroscopic scale. Furthermore, we study the dependence of these coefficients on geometrical parameters on related microscopic and macroscopic scales.

  16. 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

  17. 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

  18. Design, Materials, and Mechanobiology of Biodegradable Scaffolds for Bone Tissue Engineering

    Science.gov (United States)

    Velasco, Marco A.; Narváez-Tovar, Carlos A.; Garzón-Alvarado, Diego A.

    2015-01-01

    A review about design, manufacture, and mechanobiology of biodegradable scaffolds for bone tissue engineering is given. First, fundamental aspects about bone tissue engineering and considerations related to scaffold design are established. Second, issues related to scaffold biomaterials and manufacturing processes are discussed. Finally, mechanobiology of bone tissue and computational models developed for simulating how bone healing occurs inside a scaffold are described. PMID:25883972

  19. 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.

  20. Reduced bone formation markers, and altered trabecular and cortical bone mineral densities of non-paretic femurs observed in rats with ischemic stroke: A randomized controlled pilot study.

    Directory of Open Access Journals (Sweden)

    Karen N Borschmann

    Full Text Available Immobility and neural damage likely contribute to accelerated bone loss after stroke, and subsequent heightened fracture risk in humans.To investigate the skeletal effect of middle cerebral artery occlusion (MCAo stroke in rats and examine its utility as a model of human post-stroke bone loss.Twenty 15-week old spontaneously hypertensive male rats were randomized to MCAo or sham surgery controls. Primary outcome: group differences in trabecular bone volume fraction (BV/TV measured by Micro-CT (10.5 micron istropic voxel size at the ultra-distal femur of stroke affected left legs at day 28. Neurological impairments (stroke behavior and foot-faults and physical activity (cage monitoring were assessed at baseline, and days 1 and 27. Serum bone turnover markers (formation: N-terminal propeptide of type 1 procollagen, PINP; resorption: C-terminal telopeptide of type 1 collagen, CTX were assessed at baseline, and days 7 and 27.No effect of stroke was observed on BV/TV or physical activity, but PINP decreased by -24.5% (IQR -34.1, -10.5, p = 0.046 at day 27. In controls, cortical bone volume (5.2%, IQR 3.2, 6.9 and total volume (6.4%, IQR 1.2, 7.6 were higher in right legs compared to left legs, but these side-to-side differences were not evident in stroke animals.MCAo may negatively affect bone formation. Further investigation of limb use and physical activity patterns after MCAo is required to determine the utility of this current model as a representation of human post-stroke bone loss.

  1. The processing and characterization of animal-derived bone to yield materials with biomedical applications. Part II: milled bone powders, reprecipitated hydroxyapatite and the potential uses of these materials.

    Science.gov (United States)

    Johnson, G S; Mucalo, M R; Lorier, M A; Gieland, U; Mucha, H

    2000-11-01

    Further studies on the processing and use of animal-bone-derived calcium phosphate materials in biomedical applications are presented. Bone powders sourced either from the direct crushing and milling of bovine, ovine and cervine bone or after being subjected to defatting and acid digestion/NaOH reprecipitation and sodium hypochlorite hydrogen peroxide treatment of animal bones were characterized using Fourier transform infra-red (FTIR) spectroscopy, 13C solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, atomic absorption (AA) and inductively coupled plasma (ICP) spectrometric techniques. Bone powders were trialled for their potential use as a substrate for phosphine coupling and enzyme immobilization as well as a feedstock powder for plasma spraying on titanium metal substrates. Results indicated that enzyme immobilization by phosphine coupling could be successfully achieved on milled cervine bone with the immobilized enzyme retaining some activity. It was found that the presence of impurities normally carried down with the processing of the bone materials (viz., fat and collagen) played an important role in influencing the adsorbency and reactivity of the powders. Plasma spraying studies using reprecipitated bovine-derived powders produced highly adherent coatings on titanium metal, the composition of which was mostly hydroxyapatite (Ca10(PO4)6(OH)2) with low levels of alpha-tricalcium phosphate (alpha-Ca3(PO4)2) and tetracalcium phosphate (Ca4P2O9) also detected. In general, animal derived calcium phosphate materials constitute a potentially cheaper source of calcium phosphate materials for biomedical applications and make use of a largely under-utilized resource from abattoir wastes. Copyright 2000 Kluwer Academic Publishers

  2. An altered hormonal profile and elevated rate of bone loss are associated with low bone mass in professional horse-racing jockeys.

    Science.gov (United States)

    Dolan, Eimear; McGoldrick, Adrian; Davenport, Colin; Kelleher, Grainne; Byrne, Brendan; Tormey, William; Smith, Diarmuid; Warrington, Giles D

    2012-09-01

    Horse-racing jockeys are a group of weight-restricted athletes, who have been suggested as undertaking rapid and extreme weight cycling practices in order to comply with stipulated body-mass standards. The aim of this study was to examine bone mass, turnover and endocrine function in jockeys and to compare this group with age, gender and body mass index matched controls. Twenty male professional jockeys and 20 healthy male controls participated. Dual energy X-ray absorptiometry scans and early morning fasting blood and urine samples were used to measure bone mass, turnover and a hormonal profile. Total body bone mineral density (BMD) was significantly lower in jockeys (1.143 ± 0.05 vs. 1.27 ± 0.06 g cm(-3), p professional jockeys have an elevated rate of bone loss and reduced bone mass that appears to be associated with disrupted hormonal activity. It is likely that this may have occurred in response to the chronic weight cycling habitually experienced by this group.

  3. Chronic alcohol abuse in men alters bone mechanical properties by affecting both tissue mechanical properties and microarchitectural parameters.

    Science.gov (United States)

    Cruel, M; Granke, M; Bosser, C; Audran, M; Hoc, T

    2017-06-01

    Alcohol-induced secondary osteoporosis in men has been characterized by higher fracture prevalence and a modification of bone microarchitecture. Chronic alcohol consumption impairs bone cell activity and results in an increased fragility. A few studies highlighted effects of heavy alcohol consumption on some microarchitectural parameters of trabecular bone. But to date and to our knowledge, micro- and macro-mechanical properties of bone of alcoholic subjects have not been investigated. In the present study, mechanical properties and microarchitecture of trabecular bone samples from the iliac crest of alcoholic male patients (n=15) were analyzed and compared to a control group (n=8). Nanoindentation tests were performed to determine the tissue's micromechanical properties, micro-computed tomography was used to measure microarchitectural parameters, and numerical simulations provided the apparent mechanical properties of the samples. Compared to controls, bone tissue from alcoholic patients exhibited an increase of micromechanical properties at tissue scale, a significant decrease of apparent mechanical properties at sample scale, and significant changes in several microarchitectural parameters. In particular, a crucial role of structure model index (SMI) on mechanical properties was identified. 3D microarchitectural parameters are at least as important as bone volume fraction to predict bone fracture risk in the case of alcoholic patients. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. Comparative analysis of guided bone regeneration using autogenous tooth bone graft material with and without resorbable membrane

    Directory of Open Access Journals (Sweden)

    Ji-Young Lee

    2013-09-01

    Conclusion: Both groups showed clinically acceptable bone regeneration without any eventful complications. Within the limitation of this study, we can carefully conclude that the use of resorbable membrane is not a critical factor in GBR when using AutoBT.

  5. TiO2/bone composite materials for the separation of heavy metal impurities from waste water solutions

    Science.gov (United States)

    Dakroury, G.; Labib, Sh.; Abou El-Nour, F. H.

    2012-09-01

    Pure bone material obtained from cow meat, as apatite-rich material, and TiO2-bone composite materials are prepared and studied to be used for heavy metal ions separation from waste water solutions. Meat wastes are chemically and thermally treated to control their microstructure in order to prepare the composite materials that fulfill all the requirements to be used as selective membranes with high performance, stability and mechanical strength. The prepared materials are analyzed using Hg-porosimetry for surface characterization, energy dispersive X-ray spectroscopy (EDAX) for elemental analysis and Fourier transform infrared spectroscopy (FTIR) for chemical composition investigation. Structural studies are performed using X-ray diffraction (XRD). Microstructural properties are studied using scanning electron microscopy (SEM) and specific surface area studies are performed using Brunauer-Emmet-Teller (BET) method. XRD studies show that multiphase structures are obtained as a result of 1h sintering at 700-1200 °C for both pure bone and TiO2-bone composite materials. The factors affecting the transport of different heavy metal ions through the selected membranes are determined from permeation flux measurements. It is found that membrane pore size, membrane surface roughness and membrane surface charge are the key parameters that control the transport or rejection of heavy metal ions through the selected membranes.

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

    International Nuclear Information System (INIS)

    Qin Ling; Leung, Kwok Sui; Griffith, J.F.

    2007-01-01

    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.)

  7. A visco-poroelastic model of functional adaptation in bones reconstructed with bio-resorbable materials.

    Science.gov (United States)

    Giorgio, Ivan; Andreaus, Ugo; Scerrato, Daria; dell'Isola, Francesco

    2016-10-01

    In this paper, the phenomena of resorption and growth of bone tissue and resorption of the biomaterial inside a bicomponent system are studied by means of a numerical method based on finite elements. The material behavior is described by a poro-viscoelastic model with infiltrated voids. The mechanical stimulus that drives these processes is a linear combination of density of strain energy and viscous dissipation. The external excitation is represented by a bending load slowly variable with sinusoidal law characterized by different frequencies. Investigated aspects are the influence of the load frequency, of type of the stimulus and of the effective porosity on the time evolution of the mass densities of considered system.

  8. Type I Collagen and Strontium-Containing Mesoporous Glass Particles as Hybrid Material for 3D Printing of Bone-Like Materials.

    Science.gov (United States)

    Montalbano, Giorgia; Fiorilli, Sonia; Caneschi, Andrea; Vitale-Brovarone, Chiara

    2018-04-28

    Bone tissue engineering offers an alternative promising solution to treat a large number of bone injuries with special focus on pathological conditions, such as osteoporosis. In this scenario, the bone tissue regeneration may be promoted using bioactive and biomimetic materials able to direct cell response, while the desired scaffold architecture can be tailored by means of 3D printing technologies. In this context, our study aimed to develop a hybrid bioactive material suitable for 3D printing of scaffolds mimicking the natural composition and structure of healthy bone. Type I collagen and strontium-containing mesoporous bioactive glasses were combined to obtain suspensions able to perform a sol-gel transition under physiological conditions. Field emission scanning electron microscopy (FESEM) analyses confirmed the formation of fibrous nanostructures homogeneously embedding inorganic particles, whereas bioactivity studies demonstrated the large calcium phosphate deposition. The high-water content promoted the strontium ion release from the embedded glass particles, potentially enhancing the osteogenic behaviour of the composite. Furthermore, the suspension printability was assessed by means of rheological studies and preliminary extrusion tests, showing shear thinning and fast material recovery upon deposition. In conclusion, the reported results suggest that promising hybrid systems suitable for 3D printing of bioactive scaffolds for bone tissue engineering have been developed.

  9. Main properties of nanocrystalline hydroxyapatite as a bone graft material in treatment of periodontal defects. A review of literature

    International Nuclear Information System (INIS)

    Bayani, Mojtaba; Torabi, Sepehr; Shahnaz, Aysan; Pourali, Mohammad

    2017-01-01

    This study aims to provide a literature review on nanocrystalline hydroxyapatite (n-HA). n-HA constitutes the principle inorganic part of hard tissues. Therefore, preparation of commercial synthetic analogues, the so-called ‘biomimetic’, has gained a lot of attention since it can precisely mimic the physicochemical features of biological apatite compounds. Due to its improved osseointegrative properties, n-HA may represent a promising class of bone graft materials. n-HA binds to the bone and by stimulation of osteoblast activity and enhancing local growth factors it improves bone healing. Periodontitis is an inflammatory condition in response to microbial plaque that leads to periodontal tissue destruction and osseous defects in alveolar bone. A review of the extant literature reveals that n-HA has certain advantages in periodontal tissue regeneration including minimal patient morbidity, better biocompatibility, and lack of toxicity

  10. Characterization of biocomposites of sheep hydroxyapatite (SHA)/shellac/sugar as bone filler material

    Science.gov (United States)

    Triyono, Joko; Rizha, Yushak; Triyono, Teguh

    2018-04-01

    The use of biomaterials in orthopedics is increasing. This led to the growth of innovations in the field of medicine, one of them is the development of biomaterials. Study of Sheep Hydroxyapatite (SHA)/shellac/sugar biocomposite characterization was to determine the phase of the material, porosity, hardness and compressive strength of them. This research was conducted to develop new types of biomaterials that can be used as bone filler material. The analysis that used in this research was dry methods. The results showed that observation of XRD (X-Ray Diffraction) shows the pattern of diffraction 2θ: 31.6472°, 32.7753°, 32.0723°, The highest hardness of SHA/shellac/sugar ratio was 70:30% (7.38±0.1395 VHN) and the lowest at 50:50% (4.91±0.37 VHN). The highest Diametral Tensile Strength (DTS) test was 70:30% (5.43±1.395 MPa) and the lowest at 50:50% (3.10±0.26 MPa). SEM observations are performed to see the material porosity.

  11. 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.

  12. 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.

  13. An analysis of bones and other materials collected by Cape Vultures ...

    African Journals Online (AJOL)

    We compared bones and non-faunal items collected by Cape Vultures at the Blouberg and Kransberg colonies. Bones from the base of the nesting cliffs were on average longer than those from the crops and stomachs of birds. Bones from the Blouberg cliff base were on average shorter than those from the Kransberg.

  14. 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. © 2014 Wiley Periodicals, Inc.

  15. Carprofen neither reduces postoperative facial expression scores in rabbits treated with buprenorphine nor alters long term bone formation after maxillary sinus grafting.

    Science.gov (United States)

    Hedenqvist, Patricia; Trbakovic, Amela; Thor, Andreas; Ley, Cecilia; Ekman, Stina; Jensen-Waern, Marianne

    2016-08-01

    In connection with bilateral maxillary sinus augmentation, the acute effects of the nonsteroidal anti-inflammatory drug carprofen on facial expressions and long-term effects on bone formation were evaluated in 18 male New Zealand White rabbits. A 10×10mm bone window was drilled in the maxilla, the sinus membrane elevated and a titanium mini-implant inserted. One of two test materials was randomly inserted unilaterally and bovine bone chips (control) on the contralateral side in the created space. Rabbits were randomly allocated to receive buprenorphine plus carprofen (n=9) or buprenorphine plus saline (n=9) postoperatively. Buprenorphine was administered subcutaneously every 6h for 3days in a tapered dose (0.05-0.01mg/kg) and carprofen (5mg/kg) or saline administered subcutaneously 1h before, and daily for 4days postoperatively. To assess pain, clinical examination, body weight recording and scoring of facial expressions from photos taken before, and 6-13h after surgery were performed. Twelve weeks after surgery the rabbits were euthanized and sections of maxillary bones and sinuses were analysed with histomorphometry and by qualitative histology. Carprofen had no effect on mean facial expression scores, which increased from 0.0 to 3.6 (carprofen) and 4.3 (saline), of a maximum of 8.0. Neither did carprofen have an effect on bone formation or implant incorporation, whereas the test materials had. In conclusion, treatment with 5mg/kg carprofen once daily for 5days did not reduce facial expression scores after maxillary sinus augmentation in buprenorphine treated rabbits and did not affect long term bone formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. 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.

  18. Bone health nutraceuticals alter microarray mRNA gene expression: A randomized, parallel, open-label clinical study.

    Science.gov (United States)

    Lin, Yumei; Kazlova, Valentina; Ramakrishnan, Shyam; Murray, Mary A; Fast, David; Chandra, Amitabh; Gellenbeck, Kevin W

    2016-01-15

    Dietary intake of fruits and vegetables has been suggested to have a role in promoting bone health. More specifically, the polyphenols they contain have been linked to physiological effects related to bone mineral density and bone metabolism. In this research, we use standard microarray analyses of peripheral whole blood from post-menopausal women treated with two fixed combinations of plant extracts standardized to polyphenol content to identify differentially expressed genes relevant to bone health. In this 28-day open-label study, healthy post-menopausal women were randomized into three groups, each receiving one of three investigational fixed combinations of plant extracts: an anti-resorptive (AR) combination of pomegranate fruit (Punica granatum L.) and grape seed (Vitis vinifera L.) extracts; a bone formation (BF) combination of quercetin (Dimorphandra mollis Benth) and licorice (Glycyrrhiza glabra L.) extracts; and a fixed combination of all four plant extracts (AR plus BF). Standard microarray analysis was performed on peripheral whole blood samples taken before and after each treatment. Annotated genes were analyzed for their association to bone health by comparison to a gene library. The AR combination down-regulated a number of genes involved in reduction of bone resorption including cathepsin G (CTSG) and tachykinin receptor 1 (TACR1). The AR combination also up-regulated genes associated with formation of extracellular matrix including heparan sulfate proteoglycan 2 (HSPG2) and hyaluronoglucosaminidase 1 (HYAL1). In contrast, treatment with the BF combination resulted in up-regulation of bone morphogenetic protein 2 (BMP-2) and COL1A1 (collagen type I α1) genes which are linked to bone and collagen formation while down-regulating genes linked to osteoclastogenesis. Treatment with a combination of all four plant extracts had a distinctly different effect on gene expression than the results of the AR and BF combinations individually. These results could

  19. A metabolite of leucine (β-hydroxy-β-methylbutyrate given to sows during pregnancy alters bone development of their newborn offspring by hormonal modulation.

    Directory of Open Access Journals (Sweden)

    Tomasz Blicharski

    Full Text Available The effects of dietary β-hydroxy-β-methylbutyrate (HMB supplementation during gestation on bone, growth plate, and articular cartilage in newborns were determined. Thermal analysis of articular cartilage was performed to examine the structural changes in collagen. At day 70 of gestation, a total of 12 sows (Large White Polish breed, at the second parity were randomly assigned to two groups, with each group receiving either a basal diet or the same diet supplemented with 0.2 g/day HMB until the 90th day. Maternal HMB supplementation enhanced body weight, bone length, and diameter in males. It also improved geometric and mechanical properties contributing to increased bone morphology and endurance. In turn, alteration of the length was only observed in females. The positive effects were mediated by increased serum concentrations of insulin-like growth factor-1 and leptin. HMB-treatment enhanced the concentration of FSH, LH, estradiol, and testosterone. Serum TAP was enhanced by the HMB-treatment by 34% in females and 138% in males. Beneficial effects of the HMB-treatment on trabecular bone and content of proteoglycans in articular cartilage were shown. The HMB-treatment significantly changed the collagen structure in cartilages, especially in the females, which was demonstrated by the PSR analysis. Differences between the HMB-supplemented and the control females in the calorimetric peak temperatures were presumably related to different collagen fibril density in the articular cartilage structure. In summary, maternal HMB supplementation in the mid-gestation period significantly improved general growth and mechanical endurance of long bones by the influence on the somatotropic and pituitary-gonadal axes in the offspring.

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

    Science.gov (United States)

    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

  1. Alteration and long-term behaviour of different types of innovative materials for long-lived radionuclides confinement

    International Nuclear Information System (INIS)

    Leturcq, G.

    1998-01-01

    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)

  2. Large diameter femoral heads impose significant alterations on the strains developed on femoral component and bone: a finite element analysis.

    Science.gov (United States)

    Theodorou, E G; Provatidis, C G; Babis, G C; Georgiou, C S; Megas, P D

    2011-01-01

    Total Hip Arthroplasty aims at fully recreating a functional hip joint. Over the past years modular implant systems have become common practice and are widely used, due to the surgical options they provide. In addition Big Femoral Heads have also been implemented in the process, providing more flexibility for the surgeon. The current study aims at investigating the effects that femoral heads of bigger diameter may impose on the mechanical behavior of the bone-implant assembly. Using data acquired by Computed Tomographies and a Coordinate Measurement Machine, a cadaveric femur and a Profemur-E modular stem were fully digitized, leading to a three dimensional finite element model in ANSYS Workbench. Strains and stresses were then calculated, focusing on areas of clinical interest, based on Gruen zones: the calcar and the corresponding below the greater trochanter area in the proximal femur, the stem tip region and a profile line along linea aspera. The performed finite elements analysis revealed that the use of large diameter heads produces significant changes in strain development within the bone volume, especially in the lateral side. The application of Frost's law in bone remodeling, validated the hypothesis that for all diameters normal bone growth occurs. However, in the calcar area lower strain values were recorded, when comparing with the reference model featuring a 28mm femoral head. Along line aspera and for the stem tip area, higher values were recorded. Finally, stresses calculated on the modular neck revealed increased values, but without reaching the yield strength of the titanium alloy used.

  3. 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).

  4. Intercalated chitosan/hydroxyapatite nanocomposites: Promising materials for bone tissue engineering applications.

    Science.gov (United States)

    Nazeer, Muhammad Anwaar; Yilgör, Emel; Yilgör, Iskender

    2017-11-01

    Preparation and characterization of chitosan/hydroxyapatite (CS/HA) nanocomposites displaying an intercalated structure is reported. Hydroxyapatite was synthesized through sol-gel process. Formic acid was introduced as a new solvent to obtain stable dispersions of nano-sized HA particles in polymer solution. CS/HA dispersions with HA contents of 5, 10 and 20% by weight were prepared. Self-assembling of HA nanoparticles during the drying of the solvent cast films led to the formation of homogeneous CS/HA nanocomposites. Composite films were analyzed by scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-rays (EDX) analysis, Fourier transform infrared (FTIR) spectroscopy, X-rays diffraction (XRD) analysis and thermogravimetric analysis (TGA). SEM and AFM confirmed the presence of uniformly distributed HA nanoparticles on the chitosan matrix surface. XRD patterns and cross-sectional SEM images showed the formation of layered nanocomposites. Complete degradation of chitosan matrix in TGA experiments, led to the formation of nanoporous 3D scaffolds containing hydroxyapatite, β-tricalcium phosphate and calcium pyrophosphate. CS/HA composites can be considered as promising materials for bone tissue engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effect of modifications in mineralized collagen fibril and extra-fibrillar matrix material properties on submicroscale mechanical behavior of cortical bone.

    Science.gov (United States)

    Wang, Yaohui; Ural, Ani

    2018-06-01

    A key length scale of interest in assessing the fracture resistance of bone is the submicroscale which is composed of mineralized collagen fibrils (MCF) and extra-fibrillar matrix (EFM). Although the processes through which the submicroscale constituents of bone contribute to the fracture resistance in bone have been identified, the extent of the modifications in submicroscale mechanical response due to the changes in individual properties of MCFs and EFM has not been determined. As a result, this study aims to quantify the influence of individual MCF and EFM material property modifications on the mechanical behavior (elastic modulus, ultimate strength, and resistance to failure) of bone at the submicroscale using a novel finite element modeling approach that incorporate 3D networks of MCFs with three different orientations as well as explicit representation of EFM. The models were evaluated under tensile loading in transverse (representing MCF separation) and longitudinal (representing MCF rupture) directions. The results showed that the apparent elastic modulus at the submicroscale under both loading directions for all orientations was only affected by the change in the elastic modulus of MCFs. MCF separation and rupture strengths were mainly dependent on the ultimate strength of EFM and MCFs, respectively, with minimal influence of other material properties. The extent of damage during MCF separation increased with increasing ultimate strength of EFM and decreased with increasing fracture energy of EFM with minimal contribution from elastic modulus of MCFs. For MCF rupture, there was an almost one-to-one linear relationship between the percent change in fracture energy of MCFs and the percent change in the apparent submicroscale fracture energy. The ultimate strength and elastic modulus of MCFs had moderate to limited influence on the MCF rupture fracture energy. The results of this study quantified the extent of changes that may be seen in the energy

  6. Plug and play: combining materials and technologies to improve bone regenerative strategies

    NARCIS (Netherlands)

    Moroni, Lorenzo; Nandakumar, A.; Barrère, F.; van Blitterswijk, Clemens; Habibovic, Pamela

    2015-01-01

    Despite recent advances in the development of biomaterials intended to replace natural bone grafts for the regeneration of large, clinically relevant defects, most synthetic solutions that are currently applied in the clinic are still inferior to natural bone grafts with regard to regenerative

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

    Energy Technology Data Exchange (ETDEWEB)

    Gryshkov, Oleksandr, E-mail: gryshkov@imp.uni-hannover.de [Institute for Multiphase Processes, Leibniz Universität Hannover, 30167 Hannover (Germany); Klyui, Nickolai I., E-mail: klyuini@ukr.net [College of Physics, Jilin University, 130012 Changchun (China); V. Lashkaryov Institute of Semiconductor Physics, National Academy of Science of Ukraine, 03028 Kyiv (Ukraine); Temchenko, Volodymyr P., E-mail: tvp@isp.kiev.ua [V. Lashkaryov Institute of Semiconductor Physics, National Academy of Science of Ukraine, 03028 Kyiv (Ukraine); Kyselov, Vitalii S., E-mail: kyselov@isp.kiev.ua [V. Lashkaryov Institute of Semiconductor Physics, National Academy of Science of Ukraine, 03028 Kyiv (Ukraine); Chatterjee, Anamika, E-mail: chatterjee@imp.uni-hannover.de [Institute for Multiphase Processes, Leibniz Universität Hannover, 30167 Hannover (Germany); Belyaev, Alexander E., E-mail: belyaev@isp.kiev.ua [V. Lashkaryov Institute of Semiconductor Physics, National Academy of Science of Ukraine, 03028 Kyiv (Ukraine); Lauterboeck, Lothar, E-mail: lauterboeck@imp.uni-hannover.de [Institute for Multiphase Processes, Leibniz Universität Hannover, 30167 Hannover (Germany); Iarmolenko, Dmytro, E-mail: iarmolenko.dmytro@isp.kiev.ua [V. Lashkaryov Institute of Semiconductor Physics, National Academy of Science of Ukraine, 03028 Kyiv (Ukraine); Glasmacher, Birgit, E-mail: glasmacher@imp.uni-hannover.de [Institute for Multiphase Processes, Leibniz Universität Hannover, 30167 Hannover (Germany)

    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/ZrO{sub 2}) 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/ZrO{sub 2} 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 ZrO{sub 2} to the initial HA powder resulted in significant decomposition of the final HA/ZrO{sub 2} 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/ZrO{sub 2} 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. - Highlights: • Synthesis and characterization of porous biomorphic SiC ceramics derived from wood • Successful deposition of bioactive calcium phosphate coatings using gas detonation deposition • Porosity and pore size of Si

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

    International Nuclear Information System (INIS)

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

    2016-01-01

    Porous and cytocompatible silicon carbide (SiC) ceramics derived from wood precursors and coated with bioactive hydroxyapatite (HA) and HA-zirconium dioxide (HA/ZrO 2 ) 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/ZrO 2 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 ZrO 2 to the initial HA powder resulted in significant decomposition of the final HA/ZrO 2 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/ZrO 2 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. - Highlights: • Synthesis and characterization of porous biomorphic SiC ceramics derived from wood • Successful deposition of bioactive calcium phosphate coatings using gas detonation deposition • Porosity and pore size of SiC ceramics depend on wood

  9. 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

  10. Evaluation of the in vivo performance of composite aluminum/calcium phosphate (CAPs) as bone reconstruction material

    International Nuclear Information System (INIS)

    Araujo, P.M.; Lima, M.G.; Costa, A.C.; Pallone, E.M.

    2016-01-01

    This study aims to evaluate the in vivo performance of composite aluminum/calcium phosphate (CAPs) as bone reconstruction material. To this end, mass CAPs relative to the total weight of Al2O3 prepared Al_2O_3/CAPs using percentage of 0, 10, 20 and 30% composites. The composites characterized were by X-ray diffraction, scanning electron microscopy with scanning. After implanted in rabbit tibia randomly divided were into two groups, each with nine rabbits, according to the euthanasia period (30 days after surgery). After euthanasia was performed radiographic and histological evaluation of the grafted areas. The results confirm that the compounds Al_2O_3/CAPs presented major phase of alumina and the second phase calcium pyrophosphate. Increasing the concentration of CAPs on alumina promoted with a reduction in density and increase in porosity, as well as an increase in grain size and heterogeneity in the microstructure. Upon radiographic examination of the tibiae of the nine (9) rabbits score was observed with grade 3, or similar radiopacity presented by the remaining cortical bone. It shown was that the tibiae of rabbits with the implant showed the presence of foreign material (composite), well delimited with bone formation and bone proliferation around the implants. At the point where the composite in 30 days' time of sacrifice, there was no observable sign of infection was established, since there were observed no cellular infiltration, no rejection of the implant, concluding that the biocompatible composite was studied. (author)

  11. Characterization of the interaction between therapeutical carbon ions and bone-like materials and related impact on treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Eichhorn, Anna; Durante, Marco [GSI Helmholtzzentrum fuer Schwereionen, Darmstadt (Germany); TU Darmstadt (Germany); Carlino, Antonio [University of Palermo (Italy); Kaderka, Robert; Kraemer, Michael; La Tessa, Chiara; Scifoni, Emanuele [GSI Helmholtzzentrum fuer Schwereionen, Darmstadt (Germany)

    2013-07-01

    Radiotherapy is one of the most common and effective therapies for cancer. The treatment planning system for ions TRiP98 was developed at GSI, Darmstadt. In TRiP98, the interaction between primary radiation and tissue is modeled from experimental data measured in water and rescaled to other tissue. This approximation is not accurate enough for biological materials whose elemental composition besides density deviates significantly from water. The nuclear attenuation of carbon beams in bone-like materials was measured and an estimation of the fragmentation cross section was done. In parallel, the dose profile inhomogeneity predicted by TRiP98 at the interface between water and bones was investigated and measured at HIT (Heidelberg). A 3D treatment plan was delivered in a water phantom equipped with bone targets. Pin-point ionization chambers and X-ray dosimetric films were used for measuring the dose at different positions. As a further step, the measured cross sections of carbon ions in bone have been implemented in TRiP98. The comparison of the dose profiles calculated with the standard and benchmarked versions of the treatment planning will give an estimate of the improvement.

  12. The effects of cutting parameters on cutting forces and heat generation when drilling animal bone and biomechanical test materials.

    Science.gov (United States)

    Cseke, Akos; Heinemann, Robert

    2018-01-01

    The research presented in this paper investigated the effects of spindle speed and feed rate on the resultant cutting forces (thrust force and torque) and temperatures while drilling SawBones ® biomechanical test materials and cadaveric cortical bone (bovine and porcine femur) specimens. It also investigated cortical bone anisotropy on the cutting forces, when drilling in axial and radial directions. The cutting forces are only affected by the feed rate, whereas the cutting temperature in contrast is affected by both spindle speed and feed rate. The temperature distribution indicates friction as the primary heat source, which is caused by the rubbing of the tool margins and the already cut chips over the borehole wall. Cutting forces were considerably higher when drilling animal cortical bone, in comparison to cortical test material. Drilling direction, and therewith anisotropy, appears to have a negligible effect on the cutting forces. The results suggest that this can be attributed to the osteons being cut at an angle rather than in purely axial or radial direction, as a result of a twist drill's point angle. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  13. Nanostructured hydroxyapatite surfaces-mediated adsorption alters recognition of BMP receptor IA and bioactivity of bone morphogenetic protein-2.

    Science.gov (United States)

    Huang, Baolin; Yuan, Yuan; Ding, Sai; Li, Jianbo; Ren, Jie; Feng, Bo; Li, Tong; Gu, Yuantong; Liu, Changsheng

    2015-11-01

    Highly efficient loading of bone morphogenetic protein-2 (BMP-2) onto carriers with desirable performance is still a major challenge in the field of bone regeneration. Till now, the nanoscaled surface-induced changes of the structure and bioactivity of BMP-2 remains poorly understood. Here, the effect of nanoscaled surface on the adsorption and bioactivity of BMP-2 was investigated with a series of hydroxyapatite surfaces (HAPs): HAP crystal-coated surface (HAP), HAP crystal-coated polished surface (HAP-Pol), and sintered HAP crystal-coated surface (HAP-Sin). The adsorption dynamics of recombinant human BMP-2 (rhBMP-2) and the accessibility of the binding epitopes of adsorbed rhBMP-2 for BMP receptors (BMPRs) were examined by a quartz crystal microbalance with dissipation. Moreover, the bioactivity of adsorbed rhBMP-2 and the BMP-induced Smad signaling were investigated with C2C12 model cells. A noticeably high mass-uptake of rhBMP-2 and enhanced recognition of BMPR-IA to adsorbed rhBMP-2 were found on the HAP-Pol surface. For the rhBMP-2-adsorbed HAPs, both ALP activity and Smad signaling increased in the order of HAP-Sinuses of rhBMP-2 in clinical applications and arouse broad interests among researchers in the fields of nano-biotechnology, biomaterials and bone tissue engineering. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Permission of the alteration in nuclear fuel material processing business in the Kumatori Works of Nuclear Fuel Industries, Ltd. (report)

    International Nuclear Information System (INIS)

    1982-01-01

    A report by the Nuclear Safety Commission to the Prime Minister concerning the permission of the alteration in nuclear fuel material processing business in the Kumatori Works, Nuclear Fuel Industries Ltd., was presented. The technical capability of NFI and the safety of the business alteration were confirmed. The items of the safety examination concerning the alteration, made by the Committee on Examination of Nuclear Fuel Safety of NSC, are as follows: the aseismic design and fire prevention measures of the No.2 processing building and the No.3 waste storage building to be newly installed; criticality control concerning the No.2 processing building; the release control of gaseous and liquid wastes; the management of solid wastes; radiation control; the exposure dose of general public. (J.P.N.)

  15. The Role of Water Compartments in the Material Properties of Cortical Bone.

    Science.gov (United States)

    Granke, Mathilde; Does, Mark D; Nyman, Jeffry S

    2015-09-01

    Comprising ~20% of the volume, water is a key determinant of the mechanical behavior of cortical bone. It essentially exists in two general compartments: within pores and bound to the matrix. The amount of pore water-residing in the vascular-lacunar-canalicular space-primarily reflects intracortical porosity (i.e., open spaces within the matrix largely due to Haversian canals and resorption sites) and as such is inversely proportional to most mechanical properties of bone. Movement of water according to pressure gradients generated during dynamic loading likely confers hydraulic stiffening to the bone as well. Nonetheless, bound water is a primary contributor to the mechanical behavior of bone in that it is responsible for giving collagen the ability to confer ductility or plasticity to bone (i.e., allows deformation to continue once permanent damage begins to form in the matrix) and decreases with age along with fracture resistance. Thus, dehydration by air-drying or by solvents with less hydrogen bonding capacity causes bone to become brittle, but interestingly, it also increases stiffness and strength across the hierarchical levels of organization. Despite the importance of matrix hydration to fracture resistance, little is known about why bound water decreases with age in hydrated human bone. Using (1)H nuclear magnetic resonance (NMR), both bound and pore water concentrations in bone can be measured ex vivo because the proton relaxation times differ between the two water compartments, giving rise to two distinct signals. There are also emerging techniques to measure bound and pore water in vivo with magnetic resonance imaging (MRI). The NMR/MRI-derived bound water concentration is positively correlated with both the strength and toughness of hydrated bone and may become a useful clinical marker of fracture risk.

  16. Study of Radiation Induced Radicals in HAP and β-TCP Based Bone Graft Materials by ERP Spectroscopy

    International Nuclear Information System (INIS)

    Maltar-Strmecki, N.; Matkovic, I.

    2013-01-01

    Calcium phosphates such as beta-tricalcium phosphate (β-TCP) and hydroxyapatite (HAP) are frequently used as dental implants due to proven excellent biocompatibility. Because of their resorption in the body and direct contact with tissues, in order to inactivate bacteria, fungal spores and viruses, they are usually sterilized by γ-irradiation. However, literature provides little information about effects of γ-irradiation on the formation and stability of the free radicals in the bone graft materials during and after sterilization procedure. In this study EPR (electron paramagnetic resonance) spectroscopy was used to investigate HAP and β-TCP based dental implants present on the market. Eight dental graft materials present on the market were investigated: Bioresorb R Macropore, Poresorb R -TCP, Easy-Graft T M and Cerasorb R synthetic β-tricalcium phosphates, Easy-Graft T M crystal and Ossceram R two phase synthetic CaP consisting of 60 % HAP and 40 % β-TCP, and Dexabone R and Bio-Oss R bone graft material of bovine origin. EPR study shows that this is the only technique for characterization of free radicals that can simultaneously determine not only the presence and content, but also the position and the structure of free radicals formed by γ-sterilization in the investigated materials, as well as the paramagnetic substitutions incorporated in the materials during the synthesis (such as Mn 2+ , Fe 3+ or Cr 2+ ). Additionally, EPR provides information on stability of irradiation-induced radicals (CO 2 - , trapped H-atoms, NO 3 2 etc.) and processes for reducing them. Results show that EPR should be considered as a valuable technique in improving the quality of bone graft materials, which must be sterile, and to offer the high quality, efficacy and reliable materials to the patients.(author)

  17. Regeneration of skull bones in adult rabbits after implantation of commercial osteoinductive materials and transplantation of a tissue-engineering construct.

    Science.gov (United States)

    Volkov, A V; Alekseeva, I S; Kulakov, A A; Gol'dshtein, D V; Shustrov, S A; Shuraev, A I; Arutyunyan, I V; Bukharova, T B; Rzhaninova, A A; Bol'shakova, G B; Grigor'yan, A S

    2010-10-01

    We performed a comparative study of reparative osteogenesis in rabbits with experimental critical defects of the parietal bones after implantation of commercial osteoinductive materials "Biomatrix", "Osteomatrix", "BioOss" in combination with platelet-rich plasma and transplantation of a tissue-engineering construct on the basis of autogenic multipotent stromal cells from the adipose tissue predifferentiated in osteogenic direction. It was found that experimental reparative osteogenesis is insufficiently stimulated by implantation materials and full-thickness trepanation holes were not completely closed. After transplantation of the studied tissue-engineering construct, the defect was filled with full-length bone regenerate (in the center of the regenerate and from the maternal bone) in contrast to control and reference groups, where the bone tissue was formed only on the side of the maternal bone. On day 120 after transplantation of the tissue-engineering construct, the percent of newly-formed bone tissue in the regenerate was 24% (the total percent of bone tissue in the regenerate was 39%), which attested to active incomplete regenerative process in contrast to control and reference groups. Thus, the study demonstrated effective regeneration of the critical defects of the parietal bones in rabbits 120 days after transplantation of the tissue-engineering construct in contrast to commercial osteoplastic materials for directed bone regeneration.

  18. 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.

  19. Radiographic and histological study of perennial bone defect repair in rat calvaria after treatment with blocks of porous bovine organic graft material.

    Science.gov (United States)

    Marins, Lucele Vieira; Cestari, Tania Mary; Sottovia, André Dotto; Granjeiro, José Mauro; Taga, Rumio

    2004-03-01

    Over the last few years, various bone graft materials of bovine origin to be used in oromaxillofacial surgeries have entered the market. In the present study, we determined the capacity of a block organic bone graft material (Gen-ox, Baumer SA, Brazil) prepared from bovine cancellous bone to promote the repair of critical size bone injuries in rat calvaria. A transosseous defect measuring approximately 8mm in diameter was performed with a surgical trephine in the parietal bone of 25 rats. In 15 animals, the defects were filled with a block of graft material measuring 8mm in diameter and soaked in the animal's own blood, and in the other 10 animals the defects were only filled with blood clots. The calvariae of rats receiving the material were collected 1, 3 and 6 months after surgery, and those of animals receiving the blood clots were collected immediately and 6 months after surgery. During surgery, the graft material was found to be of easy handling and to adapt perfectly to the receptor bed after soaking in blood. The results showed that, in most animals treated, the material was slowly resorbed and served as a space filling and maintenance material, favoring angiogenesis, cell migration and adhesion, and bone neoformation from the borders of the lesion. However, a foreign body-type granulomatous reaction, with the presence of numerous giant cells preventing local bone neoformation, was observed in two animals of the 1-month subgroup and in one animal of the 3-month subgroup. These cases were interpreted as resulting from the absence of demineralization and the lack of removal of potential antigen factors during production of the biomaterial. We conclude that, with improvement in the quality control of the material production, block organic bone matrix will become a good alternative for bone defect repair in the oromaxillofacial region due to its high osteoconductive capacity.

  20. Micro-mechanical modeling of the cement-bone interface: the effect of friction, morphology and material properties on the micromechanical response.

    NARCIS (Netherlands)

    Janssen, D.; Mann, K.A.; Verdonschot, N.J.J.

    2008-01-01

    In order to gain insight into the micro-mechanical behavior of the cement-bone interface, the effect of parametric variations of frictional, morphological and material properties on the mechanical response of the cement-bone interface were analyzed using a finite element approach. Finite element

  1. Micro-mechanical modeling of the cement-bone interface: the effect of friction morphology and material properties on the micromechanical response

    NARCIS (Netherlands)

    Janssen, Dennis; Mann, Kenneth A.; Verdonschot, Nicolaas Jacobus Joseph

    2008-01-01

    In order to gain insight into the micro-mechanical behavior of the cement–bone interface, the effect of parametric variations of frictional, morphological and material properties on the mechanical response of the cement–bone interface were analyzed using a finite element approach. Finite element

  2. Does modifying the particle size distribution of a granular material (i.e., material scalping alters its shear strength?

    Directory of Open Access Journals (Sweden)

    Azéma Emilien

    2017-01-01

    Full Text Available By means of two dimensional contact dynamics simulations, we analyzed the effect of the particle size distribution (PSD on the shear strength of granular materials composed of un-breakable disks. We modelled PSDs with a normalized beta function, which allows for building S-shaped gradation curves, such as those that typically occur in soils. We systematically controlled and varied the size span and the shape of the PSD, and found that the shear strength is independent both characteristics. This implies that PSD modification procedures such as material scalping (i.e., removing the smallest and/or largest particles in the sample should not affect significantly the shear strength of the material composed of unbreakable discs. In order to explore the origins of the invariance of the shear strength with PSD, we analyzed the connectivity, force transmission, and friction mobilization in terms of anisotropies, finding that the constant shear strength is due to a subtle compensation of anisotropies.

  3. A Phex Mutation in a Murine Model of X-linked Hypophosphatemia Alters Phosphate Responsiveness of Bone Cells

    OpenAIRE

    Ichikawa, Shoji; Austin, Anthony M.; Gray, Amie K.; Econs, Michael J.

    2012-01-01

    Mutations in the PHEX gene cause X-linked hypophosphatemia (XLH). Hypophosphatemia in XLH results from increased circulating levels of a phosphaturic hormone, fibroblast growth factor 23 (FGF23), which inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D (calcitriol) synthesis. The current standard therapy for XLH – high dose phosphate and calcitriol – further increases FGF23 concentrations, suggesting that patients with XLH may have an altered response to extracellular phosphate...

  4. Loss of Asxl1 Alters Self-Renewal and Cell Fate of Bone Marrow Stromal Cell, Leading to Bohring-Opitz-like Syndrome in Mice

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2016-06-01

    Full Text Available De novo ASXL1 mutations are found in patients with Bohring-Opitz syndrome, a disease with severe developmental defects and early childhood mortality. The underlying pathologic mechanisms remain largely unknown. Using Asxl1-targeted murine models, we found that Asxl1 global loss as well as conditional deletion in osteoblasts and their progenitors led to significant bone loss and a markedly decreased number of bone marrow stromal cells (BMSCs compared with wild-type littermates. Asxl1−/− BMSCs displayed impaired self-renewal and skewed differentiation, away from osteoblasts and favoring adipocytes. RNA-sequencing analysis revealed altered expression of genes involved in cell proliferation, skeletal development, and morphogenesis. Furthermore, gene set enrichment analysis showed decreased expression of stem cell self-renewal gene signature, suggesting a role of Asxl1 in regulating the stemness of BMSCs. Importantly, re-introduction of Asxl1 normalized NANOG and OCT4 expression and restored the self-renewal capacity of Asxl1−/− BMSCs. Our study unveils a pivotal role of ASXL1 in the maintenance of BMSC functions and skeletal development.

  5. Loss of Asxl1 Alters Self-Renewal and Cell Fate of Bone Marrow Stromal Cell, Leading to Bohring-Opitz-like Syndrome in Mice.

    Science.gov (United States)

    Zhang, Peng; Xing, Caihong; Rhodes, Steven D; He, Yongzheng; Deng, Kai; Li, Zhaomin; He, Fuhong; Zhu, Caiying; Nguyen, Lihn; Zhou, Yuan; Chen, Shi; Mohammad, Khalid S; Guise, Theresa A; Abdel-Wahab, Omar; Xu, Mingjiang; Wang, Qian-Fei; Yang, Feng-Chun

    2016-06-14

    De novo ASXL1 mutations are found in patients with Bohring-Opitz syndrome, a disease with severe developmental defects and early childhood mortality. The underlying pathologic mechanisms remain largely unknown. Using Asxl1-targeted murine models, we found that Asxl1 global loss as well as conditional deletion in osteoblasts and their progenitors led to significant bone loss and a markedly decreased number of bone marrow stromal cells (BMSCs) compared with wild-type littermates. Asxl1(-/-) BMSCs displayed impaired self-renewal and skewed differentiation, away from osteoblasts and favoring adipocytes. RNA-sequencing analysis revealed altered expression of genes involved in cell proliferation, skeletal development, and morphogenesis. Furthermore, gene set enrichment analysis showed decreased expression of stem cell self-renewal gene signature, suggesting a role of Asxl1 in regulating the stemness of BMSCs. Importantly, re-introduction of Asxl1 normalized NANOG and OCT4 expression and restored the self-renewal capacity of Asxl1(-/-) BMSCs. Our study unveils a pivotal role of ASXL1 in the maintenance of BMSC functions and skeletal development. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. Volumetric analysis of bone substitute material performance within the human sinus cavity of former head and neck cancer patients: A prospective, randomized clinical trial.

    Science.gov (United States)

    Lorenz, Jonas; Eichler, Kathrin; Barbeck, Mike; Lerner, Henriette; Stübinger, Stefan; Seipel, Catherine; Vogl, Thomas J; Kovács, Adorján F; Ghanaati, Shahram; Sader, Robert A

    2016-01-01

    In numerous animal and human studies, it could be detected that in bone augmentation procedures, material's physicochemical characteristics can influence the cellular inflammatory pattern and therefore the integration in the host tissue. Histological, histomorphometrical, and clinical analyses of the integration of the biomaterial in the surrounding tissue are well established methodologies; however, they do not make a statement on volume and density changes of the augmented biomaterial. The aim of the present study was to assess the volume and density of a xenogeneic (Bio-Oss ® , BO) and a synthetic (NanoBone ® , NB) bone substitute material in split-mouth sinus augmentations in former tumor patients to complete histological and histomorphometrical assessment. Immediately and 6 months after sinus augmentation computed tomography scans were recorded, bone grafts were marked, and the volume was calculated with radiologic RIS-PACS software (General Electric Healthcare, Chalfont St. Giles, Great Britain) to determine the integration and degradation behavior of both biomaterials. Radiographic analysis revealed a volume reduction of the initial augmented bone substitute material (i.e. 100%) to 77.36 (±11.68) % in the BO-group, respectively, 75.82 (±22.28) % in the NB-group six months after augmentation. In both materials, the volume reduction was not significant. Bone density significantly increased in both groups. The presented radiological investigation presents a favorable method to obtain clinically relevant information concerning the integration and degradation behavior of bone substitute materials.

  7. Identification of proteinaceous material in the bone of the dinosaur Iguanodon.

    Science.gov (United States)

    Embery, Graham; Milner, Angela C; Waddington, Rachel J; Hall, Rachel C; Langley, Martin S; Milan, Anna M

    2003-01-01

    This study has directed attention at the search for bone-related proteins in an extract of demineralized rib bone of the 120 mya Iguanodon. The inner compact bone was demineralized and the GuCl extract resolved into 11 fractions using anion exchange chromatography, which all contained silver-reactive proteins with various amino acid profiles. Two specific fractions, iv and xi, revealed characteristics typical of contemporary phosphoproteins and proteoglycans, respectively. Fraction iv, 43-57 kDa, contained a high ratio of aspartate and serine, although no phosphate was discernable. Fraction xi contained a band of 41-47 kDa and was rich in chondroitin sulphate and hyaluronan. In addition an early eluting fraction was immunoreactive with an antibody against osteocalcin. A cancellous bone fraction from the same bone sample was also analyzed using N-terminal sequencing and revealed potential similarities with cystatin. While we do not claim to have identified the presence of intact proteins, this study has value in demonstrating that extruded extracellular matrix is protected by its capacity to induce mineralization, which subsequently is important in conserving detectable protein products in ancient skeletal tissues.

  8. 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

    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...... 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...

  9. Increased cartilage type II collagen degradation in patients with osteogenesis imperfecta used as a human model of bone type I collagen alterations.

    Science.gov (United States)

    Rousseau, Jean-Charles; Chevrel, Guillaume; Schott, Anne-Marie; Garnero, Patrick

    2010-04-01

    We investigated whether cartilage degradation is altered in adult patients with mild osteogenesis imperfecta (OI) used as a human model of bone type I collagen-related osteoarthritis (OA). Sixty-four adult patients with OI (39% women, mean age+/-SD: 37+/-12 years) and 64 healthy age-matched controls (54% women, 39+/-7 years) were included. We also compared data in 87 patients with knee OA (73% women, 63+/-8 years, mean disease duration: 6 years) and 291 age-matched controls (80% women, 62+/-10 years). Urinary C-terminal cross-linked telopeptide of type II collagen (CTX-II), a marker of cartilage degradation, urinary helical peptide of type I collagen (Helix-I), a marker of bone resorption, and the urinary ratio between non-isomerised/isomerised (alpha/beta CTX-I) type I collagen C-telopeptide, a marker of type I collagen maturation, were measured. Patients with OI had CTX-II levels similar to those of subjects with knee OA (p=0.89; mean+/-SEM; 460+/-57 ng/mmol Cr for OI group and 547+/-32 ng/mmol Cr for OA group) and significantly higher than both young (144+/-7.8 ng/mmol Cr, p<0.0001) and old controls (247+/-7 ng/mmol Cr, p<0.0001). In patients with OI, increased Helix-I (p<0.0001) and alpha/beta CTX-I (p=0.0067) were independently associated with increased CTX-II and together explained 26% of its variance (p< 0.0001). In patients with knee OA, increased levels of alpha/beta CTX-I ratio were also associated with higher CTX-II levels. Adult patients with OI or knee OA are characterized by increased cartilage type II collagen degradation, which is associated with increased type I collagen degradation for OI and lower type I collagen maturation for both OI and OA. These data suggest that both quantitative and qualitative alterations of bone type I collagen metabolism are involved in increased cartilage degradation in patients with OI or knee OA. Copyright 2009 Elsevier Inc. All rights reserved.

  10. Mechanical alterations of rabbit Achilles' tendon after immobilization correlate with bone mineral density but not with magnetic resonance or ultrasound imaging.

    Science.gov (United States)

    Trudel, Guy; Koike, Yoichi; Ramachandran, Nanthan; Doherty, Geoff; Dinh, Laurent; Lecompte, Martin; Uhthoff, Hans K

    2007-12-01

    To assess the usefulness of magnetic resonance imaging (MRI), ultrasound (US) imaging, or bone mineral density (BMD) in predicting the mechanical properties of immobilized rabbit Achilles' tendons. Experimental study. Basic university laboratory. Twenty-eight rabbits. Twelve rabbits had 1 hindlimb casted for 4 weeks and 10 rabbits were casted for 8 weeks. Contralateral legs and 12 normal hindlimbs served as controls. Achilles' tendon dimensions on MRI and US, T1- and T2-signal intensities on MRI, classification of abnormalities on MRI and US; BMD of the calcaneus with dual-energy x-ray absorptiometry. Biomechanic measures consisted of peak load, stiffness, and stress. Imaging variables were correlated with biomechanic alterations. Immobilized Achilles' tendons were weaker and showed decreased mechanical stress compared with their contralateral legs and controls (all PAchilles' tendons after immobilization. However, neither increased MRI nor US signal abnormality was found. BMD was lower in immobilized calcanei and larger in contralateral legs than controls. Only BMD correlated with both the decreased peak load (R2=.42, PAchilles' tendon. This study established weakened mechanical properties of immobilized Achilles' tendons. BMD of the calcaneus, but not MRI and US, was predictive of the mechanical alterations in immobilized Achilles' tendons. BMD may be a useful biomarker to monitor disease and recovery in Achilles' tendons.

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

    International Nuclear Information System (INIS)

    He, Fupo; Zhang, Jing; Yang, Fanwen; Zhu, Jixiang; Tian, Xiumei; Chen, Xiaoming

    2015-01-01

    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

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

    International Nuclear Information System (INIS)

    Jo, Sun Young; Youn, Min Ho; Lim, Youn Mook; Gwon, Hui Jeong; Park, Jong Seok; Nho, Young Chang

    2010-01-01

    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 ∼ 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

  13. Response of Primary Human Bone Marrow Mesenchymal Stromal Cells and Dermal Keratinocytes to Thermal Printer Materials In Vitro.

    Science.gov (United States)

    Schmelzer, Eva; Over, Patrick; Gridelli, Bruno; Gerlach, Jörg C

    Advancement in thermal three-dimensional printing techniques has greatly increased the possible applications of various materials in medical applications and tissue engineering. Yet, potential toxic effects on primary human cells have been rarely investigated. Therefore, we compared four materials commonly used in thermal printing for bioengineering, namely thermally printed acrylonitrile butadiene styrene, MED610, polycarbonate, and polylactic acid, and investigated their effects on primary human adult skin epidermal keratinocytes and bone marrow mesenchymal stromal cells (BM-MSCs) in vitro. We investigated indirect effects on both cell types caused by potential liberation of soluble substances from the materials, and also analyzed BM-MSCs in direct contact with the materials. We found that even in culture without direct contact with the materials, the culture with MED610 (and to a lesser extent acrylonitrile butadiene styrene) significantly affected keratinocytes, reducing cell numbers and proliferation marker Ki67 expression, and increasing glucose consumption, lactate secretion, and expression of differentiation-associated genes. BM-MSCs had decreased metabolic activity, and exhibited increased cell death in direct culture on the materials. MED610 and acrylonitrile butadiene styrene induced the strongest expression of genes associated to differentiation and estrogen receptor activation. In conclusion, we found strong cell-type-specific effects of the materials, suggesting that materials for applications in regenerative medicine should be carefully selected not only based on their mechanical properties but also based on their cell-type-specific biological effects.

  14. Castor oil polyurethane containing silica nanoparticles as filling material of bone defect in rats.

    Science.gov (United States)

    Nacer, Renato Silva; Poppi, Rodrigo Ré; Carvalho, Paulo de Tarso Camilo de; Silva, Baldomero Antonio Kato da; Odashiro, Alexandre Nakao; Silva, Iandara Schettert; Delben, José Renato Jurkevicz; Delben, Angela Antonia Sanches Tardivo

    2012-01-01

    To evaluate the biologic behavior of the castor polymer containing silica nanoparticles as a bone substitute in diafisary defect. Twenty seven male Rattus norvegicus albinus Wistar lineage were submitted to bone defect filled with castor oil polymer. Three experimental groups had been formed with nine animals each: (1) castor oil polymer containing only calcium carbonate; (2) castor oil polymer with calcium carbonate and doped with 5% of silica nanoparticles; (3) castor polymer with calcium carbonate doped with 10% of silica nanoparticles; 3 animals of each group were submitted to euthanasia 15, 30 and 60 days after experimental procedure, and their femurs were removed to histological evaluation. there was bone growth in all the studied groups, with a greater tendency of growth in the group 1. After 30 days all the groups presented similar results. After 60 days a greater amount of fibroblasts, osteoblasts, osteocytes and osteoclasts in group 3 was observed, with integrated activity of 3 kinds of cells involved in the bone activation-reabsorption-formation. The castor polymer associated to the silica nanoparticles is biocompatible and allows osteoconduction. The presence of osteoprogenitors cells suggests silica osteoinduction capacity.

  15. Advanced Glycation Endproducts and Bone Material Properties in Type 1 Diabetic Mice.

    Directory of Open Access Journals (Sweden)

    Mishaela R Rubin

    Full Text Available Fractures, particularly at the lower extremities and hip, are a complication of diabetes. In both type 1 (T1D and type 2 diabetes (T2D, fracture risk is disproportionately worse than that predicted from the measurement of bone mineral density. Although an explanation for this discrepancy is the presence of organic matrix abnormalities, it has not been fully elucidated how advanced glycation endproducts (AGEs relate to bone deterioration at both the macroscopic and microscopic levels. We hypothesized that there would be a relationship between skeletal AGE levels (determined by Raman microspectroscopy at specific anatomical locations and bone macroscopic and microscopic properties, as demonstrated by the biomechanical measures of crack growth and microindentation respectively. We found that in OVE26 mice, a transgenic model of severe early onset T1D, AGEs were increased by Raman (carboxymethyl-lysine [CML] wildtype (WT: 0.0143 ±0.0005 vs T1D: 0.0175 ±0.0002, p = 0.003 at the periosteal surface. These differences were associated with less tough bone in T1D by fracture mechanics (propagation toughness WT: 4.73 ± 0.32 vs T1D: 3.39 ± 0.24 NM/m1/2, p = 0.010 and by reference point indentation (indentation distance increase WT: 6.85 ± 0.44 vs T1D: 9.04 ± 0.77 μm; p = 0.043. Within T1D, higher AGEs by Raman correlated inversely with macroscopic bone toughness. These data add to the existing body of knowledge regarding AGEs and the relationship between skeletal AGEs with biomechanical indices.

  16. ANOMALY DETECTION AND COMPARATIVE ANALYSIS OF HYDROTHERMAL ALTERATION MATERIALS TROUGH HYPERSPECTRAL MULTISENSOR DATA IN THE TURRIALBA VOLCANO

    Directory of Open Access Journals (Sweden)

    J. G. Rejas

    2012-07-01

    Full Text Available 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.

  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. Evolution of the alteration process in time of granitic materials from Valdemorillo quarries used in built heritage, Madrid, Spain

    Science.gov (United States)

    Alvarez de Buergo, M.; Fort, R.; Perez-Monserrat, E. M.

    2012-04-01

    Alteration of building materials used for heritage construction already starts in the quarries, where materials are subjected to both natural alteration and anthropic decay, this latter caused by the rock extracting, cutting and carving processes. Once the materials are placed in the building, they are exposed to other agents that accelerate their decay, especially if they are exposed to aggressive environments. Materials petrophysical properties tend to vary according to the alteration degree they have experienced, the longer they have been exposed to decay agents, the greater the properties change. Surface hardness of granitic rocks tend to diminish when they deteriorate, increasing its porosity, which usually is reflected on a decrease of the ultrasound propagation velocity measurements. Ultrasound velocity and surface hardness were measured in 200 monzogranite ashlars use to build the Assumption of Our Lady church (Valdemorillo, Madrid, Spain). Ultrasound velocity was measured using the indirect transmission mode, with 54 kHz frequency transductors, and surface hardness by means of the Schmidt hammer rebound tester. This monument was erected in different building stages. The starting point was a Mozarab or Visigoth defensive tower (8th century). Templars readapt it to a castle-convent (12th and 14th centuries), the tower being converted into a higher bell-tower. During the 14th-15th centuries the Cistercian Order made significant modifications of the complex, being the construction of the Chapter House one of the last enlargements during the 17th century. The quarries located in the surroundings of the monument were used for the first building stages. In the recent fronts of these quarries that have been used along the 20th century, ultrasound and hardness measurements were performed to obtain the values of these parameters in unaltered materials to compare them to those measured in ashlars from different constructive periods. A total of 50 recent front

  19. 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.

  20. Lateral approach for maxillary sinus membrane elevation without bone materials in maxillary mucous retention cyst with immediate or delayed implant rehabilitation: case reports.

    Science.gov (United States)

    Han, Ji-Deuk; Cho, Seong-Ho; Jang, Kuk-Won; Kim, Seong-Gwang; Kim, Jung-Han; Kim, Bok-Joo; Kim, Chul-Hun

    2017-08-01

    This case series study demonstrates the possibility of successful implant rehabilitation without bone augmentation in the atrophic posterior maxilla with cystic lesion in the sinus. Sinus lift without bone graft using the lateral approach was performed. In one patient, the cyst was aspirated and simultaneous implantation under local anesthesia was performed, whereas the other cyst was removed under general anesthesia, and the sinus membrane was elevated in a second process, followed by implantation. In both cases, tapered 11.5-mm-long implants were utilized. With all of the implants, good stability and appropriate bone height were achieved. The mean bone level gain was 5.73 mm; adequate bone augmentation around the implants was shown, the sinus floor was moved apically, and the cyst was no longer radiologically detected. Completion of all of the treatments required an average of 12.5 months. The present study showed that sufficient bone formation and stable implantation in a maxilla of insufficient bone volume are possible through sinus lift without bone materials. The results serve to demonstrate, moreover, that surgical treatment of mucous retention cyst can facilitate rehabilitation. These techniques can reduce the risk of complications related to bone grafts, save money, and successfully treat antral cyst.

  1. 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.

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

    Czech Academy of Sciences Publication Activity Database

    Vagaská, Barbora; Bačáková, Lucie; Filová, Elena; Balík, Karel

    2010-01-01

    Roč. 59, č. 3 (2010), s. 309-322 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA106/06/1576; GA ČR GA106/09/1000; GA AV ČR(CZ) KAN400480701 Institutional research plan: CEZ:AV0Z50110509; CEZ:AV0Z30460519 Keywords : multi-phase composites * nanoroughness * bone implants Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.646, year: 2010

  3. [The historical materials of stomatology in the oracle bone inscriptions of the Yin-Shang Dynasties].

    Science.gov (United States)

    Li, Xiaojun; Zhu, Lang

    2015-07-01

    Some oracle bone inscriptions of the Yin-Shang Dynasties were related to the stomatology, including special terms of diseases of the mouth, tongue and teeth which were classified, and proper nouns of some special diseases. Moreover, witch doctors' exploration for the causes of oral diseases, the observation on different stages of oral diseases, and the records of oral disease treatment were also involved. All of these reflected the sprouting stage of stomatology in the Yin-Shang Dynasties in ancient China.

  4. "Ruffled border" formation on a CaP-free substrate: A first step towards osteoclast-recruiting bone-grafts materials able to re-establish bone turn-over.

    Science.gov (United States)

    Merolli, Antonio; Fung, Stephanie; Murthy, N Sanjeeva; Pashuck, E Thomas; Mao, Yong; Wu, Xiaohuan; Steele, Joseph A M; Martin, Daniel; Moghe, Prabhas V; Bromage, Timothy; Kohn, Joachim

    2018-03-21

    Osteoclasts are large multinucleated giant cells that actively resorb bone during the physiological bone turnover (BTO), which is the continuous cycle of bone resorption (by osteoclasts) followed by new bone formation (by osteoblasts). Osteoclasts secrete chemotactic signals to recruit cells for regeneration of vasculature and bone. We hypothesize that a biomaterial that attracts osteoclasts and re-establishes BTO will induce a better healing response than currently used bone graft materials. While the majority of bone regeneration efforts have focused on maximizing bone deposition, the novelty in this approach is the focus on stimulating osteoclastic resorption as the starter for BTO and its concurrent new vascularized bone formation. A biodegradable tyrosine-derived polycarbonate, E1001(1k), was chosen as the polymer base due to its ability to support bone regeneration in vivo. The polymer was functionalized with a RGD peptide or collagen I, or blended with β-tricalcium phosphate. Osteoclast attachment and early stages of active resorption were observed on all substrates. The transparency of E1001(1k) in combination with high resolution confocal imaging enabled visualization of morphological features of osteoclast activation such as the formation of the "actin ring" and the "ruffled border", which previously required destructive forms of imaging such as transmission electron microscopy. The significance of these results is twofold: (1) E1001(1k) is suitable for osteoclast attachment and supports osteoclast maturation, making it a base polymer that can be further modified to optimize stimulation of BTO and (2) the transparency of this polymer makes it a suitable analytical tool for studying osteoclast behavior.

  5. OSTEOSYNTHESIS OF THE METACARPAL BONE WITH BIOABSORBABLE MATERIALS: A CASE REPORTS

    Directory of Open Access Journals (Sweden)

    Ernest Novak

    2004-04-01

    Full Text Available Background. Recent advances in biomaterial technology make it possible to produce easy-to-handle implants for osteosynthesis with ultra-high strenght and excellent biocompatibility. Biomechanical studies have shown that fixation rigidity achieved with self-reinforced (SR pins, screws and miniplates is comparable with that of metallic fixation methods. Internal fixation by means of bioabsorbable plates, screws, and pins can be used to stabilize some fractures of small bones in the hand.We report our experience with three cases where internal fixation with a SR (poly-L/DL-lactide 70/30; SR-P (L/DL LA 70/30, BioSorbTMFX miniplates and screws was carried out for stabilization of a metacarpal shaft fracture and thumb replantation.Conclusions. After bone healing is complete, metallic osteosynthesis devices become unnecessary or can even be harmful. Metallic implant-related long-term complications and secondary removal operation are avoided by using of bioabsorbable osteosynthesis devices for metacarpal bones osteosynthesis.

  6. A novel bio-inorganic bone implant containing deglued bone

    Indian Academy of Sciences (India)

    With the aim of developing an ideal bone graft, a new bone grafting material was developed using deglued bone, chitosan and gelatin. Deglued bone (DGB) which is a by-product of bone glue industries and has the close crystallographic similarities of hydroxyapatite was used as main component in the preparation of bone ...

  7. [Fabrication of porous poly lactic acid-bone matrix gelatin composite bioactive material and its osteoinductive activity].

    Science.gov (United States)

    Zhang, Yumin; Li, Baoxing; Li, Ji

    2007-02-01

    To fabricate a novel porous bioactive composite biomaterial consisting of poly lactic acid (PLA)-bone matrix gelatin (BMG) by using the supercritical carbon dioxide fluid technique (SC-CO2) and to evaluate its osteoinductive activity. The cortical bones selected from healthy adult donors were processed into BMG by the defatting, demineralizing, and deproteinizing processes. PLA and BMG were mixed at a volume radio of 3 : 1; then, the PLA-BMG mixed material and the pure PLA material were respectively placed in the supercritical carbon dioxide reaction kettles, and were respectively added by the NaCl particles 100-200 microm in diameter for the porosity of the materials so that the porous PLA-BMG composite material and the porous PLA composite material could be formed. The mouse osteoblast-like MC3T3-E1 cells were cultured in the dulbecco's modified eagle medium (DMEM) supplemented with 10% fetal bovine serum. Then, 20 microl of the MC3T3-E1 cell suspensions containing 2 X 10(6) cells /ml were delivered into the culturing plate (24 wells/plate) made of the different materials, which were co-cultured for 2 weeks. In the PLA-BMG group, 100 microg of the crushed PLA-BMG material was contained in each well; in the PLA group, 100 microg of the crushed PLA material was contained in each well; and in the DMEM group, only DMEM was contained, which served as the control group. There were 6 wells in each group. The quantitative analysis on the calcification area was performed by the staining of the alizarin red S. The co-cultured cells were harvested and lysated in 1 ml of 0. 2% Nonidet P-40 by the ultrasonic lysating technique. Then, the ALP activity and the Ca content were measured according to the illuminations of the reagent kits. The porous PLA-BMG composite material showed a good homological porosity with a pore diameter of 50-150 microm and a good connectivity between the pores. The ALP activity, the Ca content, and the calcification area were significantly greater in

  8. Early osteoinductive human bone marrow mesenchymal stromal/stem cells support an enhanced hematopoietic cell expansion with altered chemotaxis- and adhesion-related gene expression profiles

    Energy Technology Data Exchange (ETDEWEB)

    Sugino, Noriko [Department of Hematology/Oncology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Miura, Yasuo, E-mail: ym58f5@kuhp.kyoto-u.ac.jp [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Yao, Hisayuki [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Iwasa, Masaki; Fujishiro, Aya [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Division of Gastroenterology and Hematology, Shiga University of Medical Science, Shiga 520-2192 (Japan); Fujii, Sumie [Department of Hematology/Oncology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Hirai, Hideyo [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Takaori-Kondo, Akifumi [Department of Hematology/Oncology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Ichinohe, Tatsuo [Department of Hematology and Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Maekawa, Taira [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan)

    2016-01-22

    Bone marrow (BM) microenvironment has a crucial role in supporting hematopoiesis. Here, by using a microarray analysis, we demonstrate that human BM mesenchymal stromal/stem cells (MSCs) in an early osteoinductive stage (e-MSCs) are characterized by unique hematopoiesis-associated gene expression with an enhanced hematopoiesis-supportive ability. In comparison to BM-MSCs without osteoinductive treatment, gene expression in e-MSCs was significantly altered in terms of their cell adhesion- and chemotaxis-related profiles, as identified with Gene Ontology and Gene Set Enrichment Analysis. Noteworthy, expression of the hematopoiesis-associated molecules CXCL12 and vascular cell adhesion molecule 1 was remarkably decreased in e-MSCs. e-MSCs supported an enhanced expansion of CD34{sup +} hematopoietic stem and progenitor cells, and generation of myeloid lineage cells in vitro. In addition, short-term osteoinductive treatment favored in vivo hematopoietic recovery in lethally irradiated mice that underwent BM transplantation. e-MSCs exhibited the absence of decreased stemness-associated gene expression, increased osteogenesis-associated gene expression, and apparent mineralization, thus maintaining the ability to differentiate into adipogenic cells. Our findings demonstrate the unique biological characteristics of e-MSCs as hematopoiesis-regulatory stromal cells at differentiation stage between MSCs and osteoprogenitor cells and have significant implications in developing new strategy for using pharmacological osteoinductive treatment to support hematopoiesis in hematopoietic stem and progenitor cell transplantation. - Highlights: • Human BM-MSCs in an early osteoinductive stage (e-MSCs) support hematopoiesis. • Adhesion- and chemotaxis-associated gene signatures are altered in e-MSCs. • Expression of CXCL12 and VCAM1 is remarkably decreased in e-MSCs. • e-MSCs are at differentiation stage between MSCs and osteoprogenitor cells. • Osteoinductive treatment

  9. Comparison of the mechanical properties between tantalum and nickel-titanium foams implant materials for bone ingrowth applications

    International Nuclear Information System (INIS)

    Sevilla, P.; Aparicio, C.; Planell, J.A.; Gil, F.J.

    2007-01-01

    Metallic porous materials are designed to allow the ingrowth of living tissue inside the pores and to improve the mechanical anchorage of the implant. In the present work, tantalum and nickel-titanium porous materials have been characterized. The tantalum foams were produced by vapour chemical deposition (CVD/CVI) and the NiTi foams by self-propagating high temperature synthesis (SHS). The former exhibited an open porosity ranging between 65 and 73% and for the latter it ranged between 63 and 68%. The pore sizes were between 370 and 440 μm for tantalum and between 350 and 370 μm for nickel-titanium. The Young's modulus in compression of the foams studied, especially for tantalum, were very similar to those of cancellous bone. This similitude may be relevant in order to minimize the stress shielding effect in the load transfer from the implant to bone. The strength values for NiTi foam are higher than for tantalum, especially of the strain to fracture which is about 23% for NiTi and only 8% for tantalum. The fatigue endurance limit set at 10 8 cycles is about 7.5 MPa for NiTi and 13.2 MPa for tantalum. The failure mechanisms have been studied by scanning electron microscopy

  10. Integrin expression by human osteoblasts cultured on degradable polymeric materials applicable for tissue engineered bone.

    Science.gov (United States)

    El-Amin, Saadiq F; Attawia, Mohamed; Lu, Helen H; Shah, Asist K; Chang, Richard; Hickok, Noreen J; Tuan, Rocky S; Laurencin, Cato T

    2002-01-01

    The use of biodegradable polymers in the field of orthopaedic surgery has gained increased popularity, as surgical pins and screws, and as potential biological scaffolds for repairing cartilage and bone defects. One such group of polymers that has gained considerable attention are the polyesters, poly(lactide-co-glycolide) (PLAGA) and polylactic acid (PLA), because of their minimal tissue inflammatory response, favorable biocompatibility and degradation characteristics. The objective of this study was to evaluate human osteoblastic cell adherence and growth on PLAGA and PLA scaffolds by examining integrin receptor (alpha2, alpha3, alpha4, alpha5, alpha6 and beta1) expression. Primary human osteoblastic cells isolated from trabecular bone adhered efficiently to both PLAGA and PLA, with the rate of adherence on PLAGA comparable to that of control tissue culture polystyrene (TCPS), and significantly higher than on PLA polymers at 3, 6 and 12 h. Human osteoblastic phenotypic expression, alkaline phosphatase (ALP) activity was positive on both degradable matrices, whereas osteocalcin levels were significantly higher on cells grown on PLAGA than on PLA composites. Interestingly, the integrin subunits, alpha2, alpha3, alpha4, alpha5, alpha6 and beta1 were all expressed at higher levels by osteoblasts cultured on PLAGA than those on PLA as analyzed by westerns blots and by flow cytometry. Among the integrins, alpha2, beta5 and beta1 showed the greatest difference in levels between the two surfaces. Thus, both PLA and PLAGA support osteoblastic adhesion and its accompanying engagement of integrin receptor and expression of osteocalcin and ALP. However PLAGA consistently appeared to be a better substrate for osteoblastic cells based on these parameters. This study is one of the first to investigate the ability of primary human osteoblastic cells isolated from trabecular bone to adhere to the biodegradable polymers PLAGA and PLA, and to examine the expression of their key

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

    Science.gov (United States)

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

    2017-06-01

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

  12. Sharp and blunt force trauma concealment by thermal alteration in homicides: An in-vitro experiment for methodology and protocol development in forensic anthropological analysis of burnt bones.

    Science.gov (United States)

    Macoveciuc, Ioana; Márquez-Grant, Nicholas; Horsfall, Ian; Zioupos, Peter

    2017-06-01

    Burning of human remains is one method used by perpetrators to conceal fatal trauma and expert opinions regarding the degree of skeletal evidence concealment are often disparate. This experiment aimed to reduce this incongruence in forensic anthropological interpretation of burned human remains and implicitly contribute to the development of research methodologies sufficiently robust to withstand forensic scrutiny in the courtroom. We have tested the influence of thermal alteration on pre-existing sharp and blunt trauma on twenty juvenile sheep radii in the laboratory using an automated impact testing system and an electric furnace. The testing conditions simulated a worst-case scenario where remains with pre-existing sharp or blunt trauma were exposed to burning with an intentional vehicular fire scenario in mind. All impact parameters as well as the burning conditions were based on those most commonly encountered in forensic cases and maintained constant throughout the experiment. The results have shown that signatures associated with sharp and blunt force trauma were not masked by heat exposure and highlights the potential for future standardization of fracture analysis in burned bone. Our results further emphasize the recommendation given by other experts on handling, processing and recording burned remains at the crime scene and mortuary. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. 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.

  14. 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.

  15. Histopathological Alterations after Single Epidural Injection of Ropivacaine, Methylprednizolone Acetate, or Contrast Material in Swine

    International Nuclear Information System (INIS)

    Kitsou, Maria-Chrysanthi; Kostopanagiotou, Georgia; Kalimeris, Konstantinos; Vlachodimitropoulos, Demetrios; Soultanis, Konstantinos; Batistaki, Chrysanthi; Kelekis, Alexis

    2011-01-01

    Purpose: The consequences from the injection of different types of drugs in the epidural space remains unknown. Increasing evidence suggests that localized inflammation, fibrosis, and arachnoiditis can complicate sequential epidural blockades, or even epidural contrast injection. We investigate the in vivo effect of epidural injections in the epidural space in an animal model. Materials and Methods: A group of ten male adult pigs, five punctures to each at distinct vertebral interspaces under general anesthesia, were examined, testing different drugs, used regularly in the epidural space (iopamidol, methylprednisolone acetate, ropivacaine). Each site was marked with a percutaneous hook wire marker. Histological analysis of the epidural space, the meninges, and the underlying spinal cord of the punctured sites along with staining for caspase-3 followed 20 days later. Results: The epidural space did not manifest adhesions or any other pathology, and the outer surface of the dura was not impaired in any specimen. The group that had the contrast media injection showed a higher inflammation response compared to the other groups (P = 0.001). Positive staining for caspase-3 was limited to <5% of neurons with all substances used. Conclusion: No proof of arachnoiditis and/or fibrosis was noted in the epidural space with the use of the above-described drugs. A higher inflammation rate was noted with the use of contrast media.

  16. 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.

  17. Biogeochemical alteration of dissolved organic material in the Cape Fear River Estuary as a function of freshwater discharge

    Science.gov (United States)

    Dixon, Jennifer L.; Helms, John R.; Kieber, Robert J.; Avery, G. Brooks

    2014-08-01

    This study presents the first extensive examination of the controls on optical properties of chromophoric dissolved organic matter (CDOM) within the Cape Fear River Estuary (CFRE) utilizing spectral slope ratios (SR). The application of SUVA254 values, absorption spectral slopes (S) and SR values has presented a distinct opportunity to observe compositional changes in CDOM in the CFRE that was not possible using bulk DOC and aCDOM(350) values alone. By comparing estuarine trends in CDOM spectral shape during both normal and historically low flow conditions, we found that diagenetic processing of CDOM in the CFRE is controlled primarily by riverine discharge rates. These findings suggest that the chromophoric fraction of DOM is altered during estuarine transport under low flow regimes but reaches the coastal ocean relatively unaltered under higher flow conditions. This highlights the tendency for autochthonous sources of DOC to offset photochemical losses and indicates that in situ DOC production can significantly contribute to the overall carbon load if discharge is low or sufficient biogeochemical alteration of the terrestrial DOM end-member occurs. This provides new insight into the usefulness of these optical properties into understanding the cycling, fate and transport of CDOM to the coastal ocean. SR values provide a simple but potentially powerful tool in understanding the flux, transport and impact of terrestrially derived organic material deposited in the coastal ocean.

  18. Effect of a Particulate and a Putty-Like Tricalcium Phosphate-Based Bone-grafting Material on Bone Formation, Volume Stability and Osteogenic Marker Expression after Bilateral Sinus Floor Augmentation in Humans

    Directory of Open Access Journals (Sweden)

    Christine Knabe

    2017-07-01

    Full Text Available This study examines the effect of a hyaluronic acid (HyAc containing tricalcium phosphate putty scaffold material (TCP-P and of a particulate tricalcium phosphate (TCP-G graft on bone formation, volume stability and osteogenic marker expression in biopsies sampled 6 months after bilateral sinus floor augmentation (SFA in 7 patients applying a split-mouth design. 10% autogenous bone chips were added to the grafting material during surgery. The grain size of the TCP granules was 700 to 1400 µm for TCP-G and 125 to 250 µm and 500 to 700 µm (ratio 1:1 for TCP-P. Biopsies were processed for immunohistochemical analysis of resin-embedded sections. Sections were stained for collagen type I (Col I, alkaline phosphatase (ALP, osteocalcin (OC and bone sialoprotein (BSP. Furthermore, the bone area and biomaterial area fraction were determined histomorphometrically. Cone-beam CT data recorded after SFA and 6 months later were used for calculating the graft volume at these two time points. TCP-P displayed more advantageous surgical handling properties and a significantly greater bone area fraction and smaller biomaterial area fraction. This was accompanied by significantly greater expression of Col I and BSP and in osteoblasts and osteoid and a less pronounced reduction in grafting volume with TCP-P. SFA using both types of materials resulted in formation of sufficient bone volume for facilitating stable dental implant placement with all dental implants having been in function without any complications for 6 years. Since TCP-P displayed superior surgical handling properties and greater bone formation than TCP-G, without the HyAc hydrogel matrix having any adverse effect on bone formation or graft volume stability, TCP-P can be regarded as excellent grafting material for SFA in a clinical setting. The greater bone formation observed with TCP-P may be related to the difference in grain size of the TCP granules and/or the addition of the HyAc.

  19. Comparative study of new autologous material, bone-cartilage composite graft, for ossiculoplasty with Polycel® and Titanium.

    Science.gov (United States)

    Kong, J S; Jeong, C Y; Shim, M J; Kim, W J; Yeo, S W; Park, S N

    2018-04-01

    Ossiculoplasty is a surgical procedure that recreates sound transmission of the middle ear in conductive hearing loss. Various materials have been used for ossicular reconstruction, but the most ideal material for ossiculoplasty remains controversial. The purpose of this study was to introduce a novel method of autologous ossiculoplasty, bone-cartilage composite graft (BCCG) and to compare its surgical results with different types of ossiculoplastic prostheses. A retrospective study was performed in a tertiary referral centre. Data of 275 patients who received ossiculoplasty using the three different materials of BCCG, Polycel ® and titanium were analysed according to type of ossiculoplasty: partial or total ossicular replacement prosthesis (PORP or TORP). Hearing results, complication rates and clinical parameters including age, sex, past history, preoperative diagnosis and surgery type were compared among different groups. Ossiculoplasty with BCCG showed satisfactory hearing outcomes and the lowest complication rate among the three different materials. In particular, its extrusion rate was 0%. We propose that the BCCG technique is a useful alternative method for ossiculoplasty, with proper patient selection. © 2017 John Wiley & Sons Ltd.

  20. Hydroxyapatite grafted carbon nanotubes and graphene nanosheets: Promising bone implant materials

    Science.gov (United States)

    Oyefusi, Adebola; Olanipekun, Opeyemi; Neelgund, Gururaj M.; Peterson, Deforest; Stone, Julia M.; Williams, Ebonee; Carson, Laura; Regisford, Gloria; Oki, Aderemi

    2014-11-01

    In the present study, hydroxyapatite (HA) was successfully grafted to carboxylated carbon nanotubes (CNTs) and graphene nanosheets. The HA grafted CNTs and HA-graphene nanosheets were characterized using FT-IR, TGA, SEM and X-ray diffraction. The HA grafted CNTs and graphene nanosheets (CNTs-HA and Gr-HA) were further used to examine the proliferation and differentiation rate of temperature-sensitive human fetal osteoblastic cell line (hFOB 1.19). Total protein assays and western blot analysis of osteocalcin expression were used as indicators of cell proliferation and differentiation. Results indicated that hFOB 1.19 cells proliferate and differentiate well in treatment media containing CNTs-HA and graphene-HA. Both CNTs-HA and graphene-HA could be promising nanomaterials for use as scaffolds in bone tissue engineering.

  1. Hydroxyapatite grafted carbon nanotubes and graphene nanosheets: promising bone implant materials.

    Science.gov (United States)

    Oyefusi, Adebola; Olanipekun, Opeyemi; Neelgund, Gururaj M; Peterson, Deforest; Stone, Julia M; Williams, Ebonee; Carson, Laura; Regisford, Gloria; Oki, Aderemi

    2014-11-11

    In the present study, hydroxyapatite (HA) was successfully grafted to carboxylated carbon nanotubes (CNTs) and graphene nanosheets. The HA grafted CNTs and HA-graphene nanosheets were characterized using FT-IR, TGA, SEM and X-ray diffraction. The HA grafted CNTs and graphene nanosheets (CNTs-HA and Gr-HA) were further used to examine the proliferation and differentiation rate of temperature-sensitive human fetal osteoblastic cell line (hFOB 1.19). Total protein assays and western blot analysis of osteocalcin expression were used as indicators of cell proliferation and differentiation. Results indicated that hFOB 1.19 cells proliferate and differentiate well in treatment media containing CNTs-HA and graphene-HA. Both CNTs-HA and graphene-HA could be promising nanomaterials for use as scaffolds in bone tissue engineering. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Fe and Fe-P Foam for Biodegradable Bone Replacement Material: Morphology, Corrosion Behaviour, and Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Monika Hrubovčáková

    2016-01-01

    Full Text Available Iron and iron-phosphorus open-cell foams were manufactured by a replica method based on a powder metallurgical approach to serve as a temporary biodegradable bone replacement material. Iron foams alloyed with phosphorus were prepared with the aim of enhancing the mechanical properties and manipulating the corrosion rate. Two different types of Fe-P foams containing 0.5 wt.% of P were prepared: Fe-P(I foams from a phosphated carbonyl iron powder and Fe-P(II foams from a mixture of carbonyl iron and commercial Fe3P. The microstructure of foams was analyzed using scanning electron microscopy. The mechanical properties and the corrosion behaviour were studied by compression tests and potentiodynamic polarization in Hank’s solution and a physiological saline solution. The results showed that the manufactured foams exhibited an open, interconnected, microstructure similar to that of a cancellous bone. The presence of phosphorus improved the mechanical properties of the foams and decreased the corrosion rate as compared to pure iron foams.

  3. P(3HB) based magnetic nanocomposites: smart materials for bone tissue engineering

    Czech Academy of Sciences Publication Activity Database

    Akaraonye, E.; Filip, J.; Šafaříková, Miroslava; Salih, V.; Keshavarz, T.; Knowles, J.C.; Roy, I.

    -, č. 2016 (2016), č. článku 3897592. ISSN 1687-4110 Institutional support: RVO:60077344 Keywords : composite films * dispersions * elastic moduli * intelligent materials * nanocomposites Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.871, year: 2016

  4. Dependence of the bone-to-soft-part ratios in skeletal scintigrams on the type of the malignans disease, morphological alterations visible by X-ray, laboratory parameters, age and sex of patients

    International Nuclear Information System (INIS)

    Pfeifer, H.

    1982-01-01

    This study was aimed to establish whether in tumor patients information detectable by scintigrams on diffuse pathological bone alterations can be obtained prior to or without typical foci of radioactivity being discoverable. By means of a quantitative evaluation of the scintigrams consisting in a comparison of the ratios of counting rate densities, the attempt was made to find out whether there were differences between visually ''normal'' scintigrams of patients with malignant tumors with a tendency towards metastatic spread into the skeletal system, and such same scans of patients without carcinomas showing no clinical signs of bone diseases. Laboratory values including serum creatinine as a parameter of renal function, as well as the administration of a tumor-specific therapy were additionally put in correlation with their possible influence on the accumulation of sup(99m)technetium-tin-phosphate compounds in bones. (orig./MG) [de

  5. Studies the alterations of biochemical and mineral contents in bone tissue of mus musculus due to aluminum toxicity and the protective action of desferrioxamine and deferiprone by FTIR, ICP-OES, SEM and XRD techniques.

    Science.gov (United States)

    Sivakumar, S; Khatiwada, Chandra Prasad; Sivasubramanian, J

    2014-05-21

    The present study has attempt to analyze the changes in the biochemical and mineral contents of aluminum intoxicated bone and determine the protective action of desferrioxamine (DFO) and deferiprone (DFP) by using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), inductively coupled plasma optical emission spectroscopy (ICP-OES), and scanning electron microscopy (SEM) techniques for four groups of animals such as control (Group I), aluminum intoxicated (Group II), Al+DFP (Group III) and Al+DFO+DFP (Group IV) treated groups respectively. The FTIR spectra of the aluminum intoxicated bone showed significant alteration in the biochemical constituents. The bands ratio at I1400/I877 significantly decreased from control to aluminum, but enhanced it by Al+DFP to Al+DFO+DFP treated bone tissue for treatments of 16 weeks. This result suggests that DFO and DFP are the carbonate inhibitor, recovered from chronic growth of bone diseases and pathologies. The alteration of proteins profile indicated by Amide I and Amide II, where peak area values decreased from control to aluminum respectively, but enhanced by treated with DFP (p.o.) and DFO+DFP (i.p.) respectively. The XRD analysis showed a decrease in crystallinity due to aluminum toxicity. Further, the Ca, Mg, and P contents of the aluminum exposed bone were less than those of the control group, and enhanced by treatments with DFO and DFP. The concentrations of trace elements were found by ICP-OES. Therefore, present study suggests that due to aluminum toxicity severe loss of bone minerals, decrease in the biochemical constituents and changes in the surface morphology. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Three-dimensional structure of human lamellar bone: the presence of two different materials and new insights into the hierarchical organization.

    Science.gov (United States)

    Reznikov, Natalie; Shahar, Ron; Weiner, Steve

    2014-02-01

    Lamellar bone is the most common bone type in humans. The predominant components of individual lamellae are plywood-like arrays of mineralized collagen fibrils aligned in different directions. Using a dual-beam electron microscope and the Serial Surface View (SSV) method we previously identified a small, but significantly different layer in rat lamellar bone, namely a disordered layer with collagen fibrils showing little or no preferred orientation. Here we present a 3D structural analysis of 12 SSV volumes (25 complete lamellae) from femora of 3 differently aged human individuals. We identify the ordered and disordered motifs in human bone as in the rat, with several significant differences. The ordered motif shows two major preferred orientations, perpendicular to the long axis of the bone, and aligned within 10-20° of the long axis, as well as fanning arrays. At a higher organizational level, arrays of ordered collagen fibrils are organized into 'rods' around 2 to 3μm in diameter, and the long axes of these 'rods' are parallel to the lamellar boundaries. Human bone also contains a disordered component that envelopes the rods and fills in the spaces between them. The disordered motif is especially well-defined between adjacent layers of rods. The disordered motif and its interfibrillar substance stain heavily with osmium tetroxide and Alcian blue indicating the presence of another organic component in addition to collagen. The canalicular network is confined to the disordered material, along with voids and individual collagen fibrils, some of which are also aligned more or less perpendicular to the lamellar boundaries. The organization of the ordered fibril arrays into rods enveloped in the continuous disordered structure was not observed in rat lamellar bone. We thus conclude that human lamellar bone is comprised of two distinct materials, an ordered material and a disordered material, and contains an additional hierarchical level of organization composed of

  7. 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.

  8. 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)

  9. 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 ...

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

    International Nuclear Information System (INIS)

    Singh, Atul Kumar; Gajiwala, Astrid Lobo; Rai, Ratan Kumar; Khan, Mohd Parvez; Singh, Chandan; Barbhuyan, Tarun; Vijayalakshmi, S.; Chattopadhyay, Naibedya; Sinha, Neeraj; Kumar, Ashutosh; Bellare, Jayesh R.

    2016-01-01

    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

  11. 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

  12. 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

  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. Bone substitute biomaterials

    CERN Document Server

    Mallick, K

    2014-01-01

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

  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. The influence of production conditions, starting material and deposition environment on charcoal alteration in a tropical biome.

    Science.gov (United States)

    Ascough, Philippa; Bird, Michael; Meredith, Will; Large, David; Snape, Colin; Manion, Corinne

    2014-05-01

    Natural and anthropogenic burning events are a key link in the global carbon cycle, substantially influencing atmospheric CO2 levels, and consuming c.8700 teragrams yr-1 of dry biomass [1,2,3]. An important result of this process is charcoal, when lignocellulosic structures in biomass (e.g. wood) are converted to aromatic domains with high chemical stability. Charcoal is therefore not readily re-oxidized to CO2, with estimates of 5-7 ky for the half-life of charcoal carbon in soils [3,4]. Charcoal's high carbon content coupled with high environmental resistance has led to the concept of biochar as a valuable means of global carbon sequestration, capable of carbon offsets comparable to annual anthropogenic fuel emissions [5,6,7]. Charcoal is not, however, an environmentally inert substance, and at least some components of charcoal are susceptible to alteration in depositional environments. Despite the importance of charcoal in global carbon cycling, the mechanisms by which charcoal is altered in the environment remain, as yet, poorly understood. This fact limits our ability to properly incorporate both natural environmental charcoal and biochar into global carbon budgets. This study aimed to improve understanding of charcoal alteration in the environment by examining the influence of production conditions, starting material and deposition environment on the physical and chemical characteristics of charcoal at a field site in the Daintree rainforest. These factors have been identified as critical in determining the dynamics of charcoal in depositional environments [8,9] and climatic conditions at the field site (in Tropical Queensland, Australia) are likely to result in extensive alteration of charcoal. Charcoal from wood (Nothofagus spp.), algae (Enteromorpha spp.), and sugarcane (Saccharum spp.) biomass was produced at temperatures over 300-500°C and exposed to conditions of varying pH and vegetation cover. The effect of these variables on charcoal chemistry

  18. 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.

  19. Anorexia Nervosa and Bone

    Science.gov (United States)

    Misra, Madhusmita; Klibanski, Anne

    2014-01-01

    Anorexia nervosa (AN) is a condition of severe low weight that is associated with low bone mass, impaired bone structure and reduced bone strength, all of which contribute to increased fracture risk., Adolescents with AN have decreased rates of bone accrual compared with normal-weight controls, raising addition concerns of suboptimal peak bone mass and future bone health in this age group. Changes in lean mass and compartmental fat depots, hormonal alterations secondary to nutritional factors contribute to impaired bone metabolism in AN. The best strategy to improve bone density is to regain weight and menstrual function. Oral estrogen-progesterone combinations are not effective in increasing bone density in adults or adolescents with AN, and transdermal testosterone replacement is not effective in increasing bone density in adult women with AN. However, physiologic estrogen replacement as transdermal estradiol with cyclic progesterone does increase bone accrual rates in adolescents with AN to approximate that in normal-weight controls, leading to a maintenance of bone density Z-scores. A recent study has shown that risedronate increases bone density at the spine and hip in adult women with AN. However, bisphosphonates should be used with great caution in women of reproductive age given their long half-life and potential for teratogenicity, and should be considered only in patients with low bone density and clinically significant fractures when non-pharmacological therapies for weight gain are ineffective. Further studies are necessary to determine the best therapeutic strategies for low bone density in AN. PMID:24898127

  20. Micro-mechanical modeling of the cement-bone interface: the effect of friction, morphology and material properties on the micromechanical response.

    Science.gov (United States)

    Janssen, Dennis; Mann, Kenneth A; Verdonschot, Nico

    2008-11-14

    In order to gain insight into the micro-mechanical behavior of the cement-bone interface, the effect of parametric variations of frictional, morphological and material properties on the mechanical response of the cement-bone interface were analyzed using a finite element approach. Finite element models of a cement-bone interface specimen were created from micro-computed tomography data of a physical specimen that was sectioned from an in vitro cemented total hip arthroplasty. In five models the friction coefficient was varied (mu=0.0; 0.3; 0.7; 1.0 and 3.0), while in one model an ideally bonded interface was assumed. In two models cement interface gaps and an optimal cement penetration were simulated. Finally, the effect of bone cement stiffness variations was simulated (2.0 and 2.5 GPa, relative to the default 3.0 GPa). All models were loaded for a cycle of fully reversible tension-compression. From the simulated stress-displacement curves the interface deformation, stiffness and hysteresis were calculated. The results indicate that in the current model the mechanical properties of the cement-bone interface were caused by frictional phenomena at the shape-closed interlock rather than by adhesive properties of the cement. Our findings furthermore show that in our model maximizing cement penetration improved the micromechanical response of the cement-bone interface stiffness, while interface gaps had a detrimental effect. Relative to the frictional and morphological variations, variations in the cement stiffness had only a modest effect on the micro-mechanical behavior of the cement-bone interface. The current study provides information that may help to better understand the load-transfer mechanisms taking place at the cement-bone interface.

  1. 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.

  2. Evaluation of the sealing ability of bone cement as furcation perforation repair material when compared with mineral trioxide aggregate and calcium phosphate cement: An in-vitro study

    Directory of Open Access Journals (Sweden)

    Rashmi Chordiya

    2010-01-01

    Full Text Available Aim: This study was undertaken to compare the sealing ability of bone cement as furcation perforation repair material when compared with mineral trioxide aggregate and calcium phosphate cement. Materials and Methods: A total of 70 sound mandibular molars were selected for this study. The sample teeth were randomly divided into five groups: group I - n=20, perforation repair material used, mineral trioxide aggregate; group II - n=20, perforation repair material used, calcium phosphate cement; group III - n=20, perforation repair material used, bone cement; group IV - positive control, n=5, the furcation were not repaired with any material; group V - negative control, n=5, furcation area intact, no perforation done. The teeth were immersed in silver nitrate solution for 2 hours and then rinsed with photographic developer solution for 6 hours. They were then sectioned in a longitudinal direction and examined under a stereomicroscope. In each section the actual values of dye leakage were calculated from outer margins of perforation to the level of pulpal floor and were then subjected to statistical analysis. Results: An unpaired ′t′ test revealed that different groups exhibited significantly different dye penetrations (P<0.01. Conclusion: Furcation perforation repaired with MTA showed minimum microleakage (mean 54.5%, calcium phosphate cement showed maximum microleakage (100%, and bone cement showed moderate dye leakage (87.8%.

  3. 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

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

    International Nuclear Information System (INIS)

    Sharma, Gulshan B.; Robertson, Douglas D.

    2013-01-01

    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

  5. A comparison of three materials used in ESR dosimetry: L-α-alanine, DL-α-alanine and standard bone powder. Response to Co-60 gamma radiation

    International Nuclear Information System (INIS)

    Stuglik, Z.; Sadlo, J.

    1995-01-01

    Three solid state materials: L-α-alanine, DL-α-alanine and standard bone powder were irradiated with gamma analyzed with ESR method. It was stated that the G-value of paramagnetic centres in L-α-alanine is practically the same as in DL-alpha-alanine and about 50 times higher than in non-deproteinized bone powder. The sensitivities of investigated materials are proportional to their G-values if double integrals of ESR signals are chosen as a measure of radiation effects. When first derivatives of ESR absorption bands are used to the construction of dose-response curves (peak-to-peak method) the sensitivities of all investigated materials are comparable. (author). 14 refs, 1 fig., 3 tabs

  6. Multifunctional zirconium oxide doped chitosan based hybrid nanocomposites as bone tissue engineering materials.

    Science.gov (United States)

    Bhowmick, Arundhati; Jana, Piyali; Pramanik, Nilkamal; Mitra, Tapas; Banerjee, Sovan Lal; Gnanamani, Arumugam; Das, Manas; Kundu, Patit Paban

    2016-10-20

    This paper reports the development of multifunctional zirconium oxide (ZrO2) doped nancomposites having chitosan (CTS), organically modified montmorillonite (OMMT) and nano-hydroxyapatite (HAP). Formation of these nanocomposites was confirmed by various characterization techniques such as Fourier transform infrared spectroscopy and powder X-ray diffraction. Scanning electron microscopy images revealed uniform distribution of OMMT and nano-HAP-ZrO2 into CTS matrix. Powder XRD study and TEM study revealed that OMMT has partially exfoliated into the polymer matrix. Enhanced mechanical properties in comparison to the reported literature were obtained after the addition of ZrO2 nanoparticle into the nanocomposites. In rheological measurements, CMZH I-III exhibited greater storage modulus (G') than loss modulus (G″). TGA results showed that these nanocomposites are thermally more stable compare to pure CTS film. Strong antibacterial zone of inhibition and the lowest minimum inhibition concentration (MIC) value of these nanocomposites against bacterial strains proved that these materials have the ability to prevent bacterial infection in orthopedic implants. Compatibility of these nanocomposites with pH and blood of human body was established. It was observed from the swelling study that the swelling percentage was increased with decreasing the hydrophobic OMMT content. Human osteoblastic MG-63 cell proliferations were observed on the nanocomposites and cytocompatibility of these nanocomposites was also established. Moreover, addition of 5wt% OMMT and 5wt% nano-HAP-ZrO2 into 90wt% CTS matrix provides maximum tensile strength, storage modulus, aqueous swelling and cytocompatibility along with strong antibacterial effect, pH and erythrocyte compatibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. An open source software tool to assign the material properties of bone for ABAQUS finite element simulations.

    Science.gov (United States)

    Pegg, Elise C; Gill, Harinderjit S

    2016-09-06

    A new software tool to assign the material properties of bone to an ABAQUS finite element mesh was created and compared with Bonemat, a similar tool originally designed to work with Ansys finite element models. Our software tool (py_bonemat_abaqus) was written in Python, which is the chosen scripting language for ABAQUS. The purpose of this study was to compare the software packages in terms of the material assignment calculation and processing speed. Three element types were compared (linear hexahedral (C3D8), linear tetrahedral (C3D4) and quadratic tetrahedral elements (C3D10)), both individually and as part of a mesh. Comparisons were made using a CT scan of a hemi-pelvis as a test case. A small difference, of -0.05kPa on average, was found between Bonemat version 3.1 (the current version) and our Python package. Errors were found in the previous release of Bonemat (version 3.0 downloaded from www.biomedtown.org) during calculation of the quadratic tetrahedron Jacobian, and conversion of the apparent density to modulus when integrating over the Young׳s modulus field. These issues caused up to 2GPa error in the modulus assignment. For these reasons, we recommend users upgrade to the most recent release of Bonemat. Processing speeds were assessed for the three different element types. Our Python package took significantly longer (110s on average) to perform the calculations compared with the Bonemat software (10s). Nevertheless, the workflow advantages of the package and added functionality makes 'py_bonemat_abaqus' a useful tool for ABAQUS users. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. 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

  9. 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

  10. Lightweight Open-Cell Scaffolds from Sea Urchin Spines with Superior Material Properties for Bone Defect Repair.

    Science.gov (United States)

    Cao, Lei; Li, Xiaokang; Zhou, Xiaoshu; Li, Yong; Vecchio, Kenneth S; Yang, Lina; Cui, Wei; Yang, Rui; Zhu, Yue; Guo, Zheng; Zhang, Xing

    2017-03-22

    Sea urchin spines (Heterocentrotus mammillatus), with a hierarchical open-cell structure similar to that of human trabecular bone and superior mechanical property (compressive strength ∼43.4 MPa) suitable for machining to shape, were explored for potential applications of bone defect repair. Finite element analyses reveal that the compressive stress concentrates along the dense growth rings and dissipates through strut structures of the stereoms, indicating that the exquisite mesostructures play an important role in high strength-to-weight ratios. The fracture strength of magnesium-substituted tricalcium phosphate (β-TCMP) scaffolds produced by hydrothermal conversion of urchin spines is about 9.3 MPa, comparable to that of human trabecular bone. New bone forms along outer surfaces of β-TCMP scaffolds after implantation in rabbit femoral defects for one month and grows into the majority of the inner open-cell spaces postoperation in three months, showing tight interface between the scaffold and regenerative bone tissue. Fusion of beagle lumbar facet joints using a Ti-6Al-4V cage and β-TCMP scaffold can be completed within seven months with obvious biodegradation of the β-TCMP scaffold, which is nearly completely degraded and replaced by newly formed bone ten months after implantation. Thus, sea urchin spines suitable for machining to shape have advantages for production of biodegradable artificial grafts for bone defect repair.

  11. 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

  12. Mechanisms of diabetes mellitus-induced bone fragility

    DEFF Research Database (Denmark)

    Napoli, Nicola; Chandran, Manju; Pierroz, Dominique D

    2017-01-01

    The risk of fragility fractures is increased in patients with either type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM). Although BMD is decreased in T1DM, BMD in T2DM is often normal or even slightly elevated compared with an age-matched control population. However, in both T1DM...... and T2DM, bone turnover is decreased and the bone material properties and microstructure of bone are altered; the latter particularly so when microvascular complications are present. The pathophysiological mechanisms underlying bone fragility in diabetes mellitus are complex, and include hyperglycaemia......-induced hypoglycaemia, certain antidiabetic medications with a direct effect on bone and mineral metabolism (such as thiazolidinediones), as well as an increased propensity for falls, all contribute to the increased fracture risk in patients with diabetes mellitus....

  13. Bone tumors

    International Nuclear Information System (INIS)

    Unni, K.K.

    1988-01-01

    This book contains the proceedings on bone tumors. Topics covered include: Bone tumor imaging: Contribution of CT and MRI, staging of bone tumors, perind cell tumors of bone, and metastatic bone disease

  14. Alterations in vitamin D metabolite, parathyroid hormone and fibroblast growth factor-23 concentrations in sclerostin-deficient mice permit the maintenance of a high bone mass.

    Science.gov (United States)

    Ryan, Zachary C; Craig, Theodore A; McGee-Lawrence, Meghan; Westendorf, Jennifer J; Kumar, Rajiv

    2015-04-01

    Humans with mutations of the sclerostin (SOST) gene, and knockout animals in which the Sost gene has been experimentally deleted, exhibit an increase in bone mass. We review the mechanisms by which Sost knockout mice are able to accrete increased amounts of calcium and phosphorus required for the maintenance of a high bone mass. Recently published information from our laboratory, shows that bone mass is increased in Sost-deficient mice through an increase in osteoblast and a decrease in osteoclast activity, which is mediated by activation of β-catenin and an increase in prostacyclin synthesis in osteocytes and osteoblasts. The increases in calcium and phosphorus retention required for enhanced bone mineral accretion are brought about by changes in the vitamin D endocrine system, parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF-23). Thus, in Sost knockout mice, concentrations of serum 1,25-dihydroxyvitamin D (1,25(OH)2D) are increased and concentrations of FGF-23 are decreased thereby allowing a positive calcium and phosphorus balance. Additionally, in the absence of Sost expression, urinary calcium is decreased, either through a direct effect of sclerostin on renal calcium handling, or through its effect on the synthesis of 1,25(OH)2D. Adaptations in vitamin D, PTH and FGF-23 physiology occur in the absence of sclerostin expression and mediate increased calcium and phosphorus retention required for the increase in bone mineralization. This article is part of a Special Issue entitled '17th Vitamin D Workshop'. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Understanding the processes involved in weathering and experimental alteration of glassy materials. The case of some volcanic glasses from eastern Sicily (Italy)

    International Nuclear Information System (INIS)

    Liotta, Angelo

    2014-01-01

    The objective of this thesis is to study the effects of weathering and experimental alteration in order to understand the geochemical processes involved and the variation of mineral phases in altered natural glasses. For the first time, five samples of natural volcanic glasses having different composition were collected in eastern Sicily (Italy) in order to be artificially altered and analyzed. The study of naturally altered samples has allowed to observe the effects of weathering after a period of time corresponding to the age of the sample. Moreover, the use of samples of natural glass of volcanic origin has allowed to obtain some powder or thin plates of fresh silicate glass that have been subjected to artificial alteration in the laboratory, in order to model the geochemical processes that have occurred. Alteration experiments were conducted in pure water at 90 C; samples have been altered from 1 to 1000 days of experiment. The characterization of the samples was obtained by Raman spectroscopy, which showed the effects of the devitrification and the presence of some secondary minerals such as carbonates and anatase on the obsidian thin plates, but also phillipsite and chabazite, two varieties of zeolite usually found in the cavities of oldest basalts. Solid modifications were observed by SEM. The analysis showed the formation of several secondary minerals having a composition compatible with smectites, determined by EDS spectroscopy. All these results allow to test the geochemical modeling in the long term. Further analysis will be needed to reach a full understanding of the weathering of glassy materials. (author)

  16. Effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of hydroxyapatite-collagen composites as artificial bone materials

    Energy Technology Data Exchange (ETDEWEB)

    Yunoki, Shunji [Life Science Group, Tokyo Metropolitan Industrial Technology Research Institute, 2-11-1 Fukasawa, Setagaya-ku, Tokyo 158-0081 (Japan); Sugiura, Hiroaki; Kondo, Eiji; Yasuda, Kazunori [Department of Sports Medicine and Joint Surgery, Graduate School of Medicine, Hokkaido University, Kita-15 Nishi-7, Sapporo, Hokkaido 060-8638 Japan (Japan); Ikoma, Toshiyuki; Tanaka, Junzo, E-mail: yunoki.shunji@iri-tokyo.jp [Department of Metallurgy and Ceramics Science, 2-12-1-S7-1, Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

    2011-02-15

    The aim of this study was to evaluate the effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of porous hydroxyapatite (HAp)-collagen composites as artificial bone materials. Seven types of porous HAp-collagen composites were prepared from HAp nanocrystals and dense collagen fibrils. Their densities and HAp/collagen weight ratios ranged from 122 to 331 mg cm{sup -3} and from 20/80 to 80/20, respectively. The flexural modulus and strength increased with an increase in density, reaching 2.46 {+-} 0.48 and 0.651 {+-} 0.103 MPa, respectively. The porous composites with a higher collagen-matrix density exhibited much higher mechanical properties at the same densities, suggesting that increasing the collagen-matrix density is an effective way of improving the mechanical properties. It was also suggested that other structural factors in addition to collagen-matrix density are required to achieve bone-like mechanical properties. The in vivo absorbability of the composites was investigated in bone defects of rabbit femurs, demonstrating that the absorption rate decreased with increases in the composite density. An exhaustive increase in density is probably limited by decreases in absorbability as artificial bones.

  17. Effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of hydroxyapatite-collagen composites as artificial bone materials

    International Nuclear Information System (INIS)

    Yunoki, Shunji; Sugiura, Hiroaki; Kondo, Eiji; Yasuda, Kazunori; Ikoma, Toshiyuki; Tanaka, Junzo

    2011-01-01

    The aim of this study was to evaluate the effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of porous hydroxyapatite (HAp)-collagen composites as artificial bone materials. Seven types of porous HAp-collagen composites were prepared from HAp nanocrystals and dense collagen fibrils. Their densities and HAp/collagen weight ratios ranged from 122 to 331 mg cm -3 and from 20/80 to 80/20, respectively. The flexural modulus and strength increased with an increase in density, reaching 2.46 ± 0.48 and 0.651 ± 0.103 MPa, respectively. The porous composites with a higher collagen-matrix density exhibited much higher mechanical properties at the same densities, suggesting that increasing the collagen-matrix density is an effective way of improving the mechanical properties. It was also suggested that other structural factors in addition to collagen-matrix density are required to achieve bone-like mechanical properties. The in vivo absorbability of the composites was investigated in bone defects of rabbit femurs, demonstrating that the absorption rate decreased with increases in the composite density. An exhaustive increase in density is probably limited by decreases in absorbability as artificial bones.

  18. Comparison of the Influence of Phospholipid-Coated Porous Ti-6Al-4V Material on the Osteosarcoma Cell Line Saos-2 and Primary Human Bone Derived Cells

    Directory of Open Access Journals (Sweden)

    Axel Deing

    2016-03-01

    Full Text Available Biomaterial surface functionalization remains of great interest in the promotion of cell osteogenic induction. Previous studies highlighted the positive effects of porous Ti-6Al-4V and phospholipid coating on osteoblast differentiation and bone remodeling. Therefore, the first objective of this study was to evaluate the potential synergistic effects of material porosity and phospholipid coating. Primary human osteoblasts and Saos-2 cells were cultured on different Ti-6Al-4V specimens (mirror-like polished or porous specimens and were coated or not with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE for three weeks or five weeks. Selected gene expressions (e.g., classical bone markers: alkaline phosphatase, osteocalcin, osteoprotegerin (OPG, receptor activator of nuclear factor kappa-β ligand (RANKL and runt-related transcription factor 2 were estimated in vitro. Furthermore, the expressions of osteocalcin and osteopontin were examined via fluorescent microscopy at five weeks (immunocytochemistry. Consequently, it was observed that phospholipid coating potentiates preferences for low and high porosities in Saos-2 and primary cells, respectively, at the gene and protein levels. Additionally, RANKL and OPG exhibited different gene expression patterns; primary cells showed dramatically increased RANKL expression, whereas OPG expression was decreased in the presence of POPE. A synergistic effect of increased porosity and phospholipid coating was observed in primary osteoblasts in bone remodeling. This study showed the advantage of primary cells over the standard bone cell model.

  19. 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. © 2016 John Wiley & Sons Australia, Ltd.

  20. Influence of bioactive material coating of Ti dental implant surfaces on early healing and osseointegration of bone

    International Nuclear Information System (INIS)

    Yeo, In-Sung; Min, Seung-Ki; An, Young-Bai

    2010-01-01

    The dental implant surface type is one of many factors that determine the long-term clinical success of implant restoration. The implant surface consists of bioinert titanium oxide, but recently coatings with bioactive calcium phosphate ceramics have often been used on Ti implant surfaces. Bio-active surfaces are known to significantly improve the healing time of the human bone around the inserted dental implant. In this study, we characterized two types of coated implant surfaces by scanning electron microscopy, energy dispersive spectrometry, and surface roughness testing. The effect of surface modification on early bone healing was then tested by using the rabbit tibia model to measure bone-to-implant contact ratios and removal torque values. These modified surfaces showed different characteristics in terms of surface topography, chemical composition, and surface roughness. However, no significant differences were found in the bone-to-implant contact and the resistance to removal torque between these surfaces. Both the coated implants may induce similar favorable early bone responses in terms of the early functioning and healing of dental implants even though they differed in their surface characteristics.

  1. 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.

  2. The potential of materials analysis by electron rutherford backscattering as illustrated by a case study of mouse bones and related compounds.

    Science.gov (United States)

    Vos, Maarten; Tökési, Károly; Benkö, Ilona

    2013-06-01

    Electron Rutherford backscattering (ERBS) is a new technique that could be developed into a tool for materials analysis. Here we try to establish a methodology for the use of ERBS for materials analysis of more complex samples using bone minerals as a test case. For this purpose, we also studied several reference samples containing Ca: calcium carbonate (CaCO(3)) and hydroxyapatite and mouse bone powder. A very good understanding of the spectra of CaCO(3) and hydroxyapatite was obtained. Quantitative interpretation of the bone spectrum is more challenging. A good fit of these spectra is only obtained with the same peak widths as used for the hydroxyapatite sample, if one allows for the presence of impurity atoms with a mass close to that of Na and Mg. Our conclusion is that a meaningful interpretation of spectra of more complex samples in terms of composition is indeed possible, but only if widths of the peaks contributing to the spectra are known. Knowledge of the peak widths can either be developed by the study of reference samples (as was done here) or potentially be derived from theory.

  3. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    Directory of Open Access Journals (Sweden)

    Ji Cheol Bae

    2017-12-01

    Full Text Available In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL/β-tricalcium phosphate (β-TCP/bone decellularized extracellular matrix (bdECM scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, % but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %. Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results.

  4. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    Science.gov (United States)

    Bae, Ji Cheol; Lee, Jin-Ju; Shim, Jin-Hyung; Park, Keun-Ho; Lee, Jeong-Seok; Bae, Eun-Bin; Choi, Jae-Won; Huh, Jung-Bo

    2017-01-01

    In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP)/bone decellularized extracellular matrix (bdECM) scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT) to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, %) but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %). Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results. PMID:29258172

  5. Proximal alveolar bone loss in a longitudinal radiographic investigation. III. Some predictors with a possible influence on the progress in an unselected material

    Energy Technology Data Exchange (ETDEWEB)

    Bolin, A.; Lavstedt, S.; Henrikson, C.O.; Frithiof, L.

    1986-01-01

    The difference in proximal alveolar bone height between 1970 and 1980, the /sup A/BD index/sup ,/ has been measured longitudinally in radiographs from an unselected material. The group constitutes 406 individuals born in 1904 - 1952 in the county of Stockholm. 13 of 18 predictors determined in 1970 were significantly related to the ABD index in the simple correlation analyses. The predictor /sup t/he alveolar bone loss 1970/sup /(ABL index 1970) had the strongest correlation to the ABD index. In the stepwise multiple regression analysis the predictor ABL index 1970 and three other predictors reached significant levels. These were age, number of lost teeth and Russell's Periodontal Index. 21 refs.

  6. Animal Bone Remnants from Trench CLXII of the Bolgar City Site: Some New Methods of Archaeozoological Materials Processing and Evaluation

    Directory of Open Access Journals (Sweden)

    Yavorskaya Lilia V.

    2012-03-01

    Full Text Available It is for the first time in the study of animal bone remnants from the Bolgar city site that modern techniques have been applied, which have made it possible to solve archaeological and historical problems rather than purely biological ones. A detailed description of the work process based on these techniques and of the results obtained is offered. In particular, it has been found out that the cattle intended for slaughter in Bolgar had not been bred within the city limits but rather supplied from outside. Also for the first time, a change in the distribution structure of finds of wild animals’ bones as per chronological periods has been recorded.

  7. On permission of alteration of business of processing nuclear fuel materials in Japan Nuclear Fuel Co., Ltd

    International Nuclear Information System (INIS)

    1985-01-01

    The Nuclear Safety Commission sent the report on this matter to the Prime Minister on December 13, 1984, upon having received the report from the Committee on Examination of Nuclear Fuel Safety and after the deliberation. It was recognized that the technical capability of the applicant is appropriate. Also it was judged that the safety after the alteration of the processing facilities can be ensured. The alteration of the processing facilities is as follows. According to the revision of production, the maximum processing capacity is changed from 750 t U/year to 640 t U/year, and accompanying this change, the maximum processing capacity of the assembling facilities is changed from 850 t U/year to 640 t U/year. The installation of the assembling plant with 295 t U/year capacity in No.2 shop is abolished, and the capacity of the assembling plant in No.1 shop is increased from 555 t U/year to 640 t U/year. No.2 fuel assembly preserving area is set up in No.2 shop, and its capacity is changed from 24 t UO 2 to 170 t UO 2 . By the examination of criticality control and radiation control, the safety of this alteration was confirmed. (Kako, I.)

  8. 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.

  9. Are osseous artefacts a window to perishable material culture? Implications of an unusually complex bone tool from the Late Pleistocene of East Timor.

    Science.gov (United States)

    O'Connor, S; Robertson, G; Aplin, K P

    2014-02-01

    We report the discovery of an unusually complex and regionally unique bone artefact in a Late Pleistocene archaeological assemblage (c. 35 ka [thousands of years ago]) from the site of Matja Kuru 2 on the island of Timor, in Wallacea. The artefact is interpreted as the broken butt of a formerly hafted projectile point, and it preserves evidence of a complex hafting mechanism including insertion into a shaped or split shaft, a complex pattern of binding including lateral stabilization of the cordage within a bilateral series of notches, and the application of mastic at several stages in the hafting process. The artefact provides the earliest direct evidence for the use of this combination of hafting technologies in the wider region of Southeast Asia, Wallacea, Melanesia and Australasia, and is morphologically unparallelled in deposits of any age. By contrast, it bears a close morphological resemblance to certain bone artefacts from the Middle Stone Age of Africa and South Asia. Examination of ethnographic projectile technology from the region of Melanesia and Australasia shows that all of the technological elements observed in the Matja Kuru 2 artefact were in use historically in the region, including the unusual feature of bilateral notching to stabilize a hafted point. This artefact challenges the notion that complex bone-working and hafting technologies were a relatively late innovation in this part of the world. Moreover, its regional uniqueness encourages us to abandon the perception of bone artefacts as a discrete class of material culture, and to adopt a new interpretative framework in which they are treated as manifestations of a more general class of artefacts that more typically were produced on perishable raw materials including wood. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  10. Early effect of platelet-rich plasma on bone healing 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.

    2007-01-01

    OBJECTIVE: The early effect of platelet-rich plasma (PRP) on bone regeneration in combination with dense biphasic hydroxyl apatite (HA)/beta-tricalcium phosphate (TCP) particles (ratio 60%/40%) was evaluated in rat cranial defects with a diameter of 6.2 mm. We hypothesize that PRP exerts its

  11. Experimental and computational analysis of micromotions of an uncemented femoral knee implant using elastic and plastic bone material models

    NARCIS (Netherlands)

    Berahmani, Sanaz; Janssen, Dennis; Verdonschot, Nico

    2017-01-01

    It is essential to calculate micromotions at the bone-implant interface of an uncemented femoral total knee replacement (TKR) using a reliable computational model. In the current study, experimental measurements of micromotions were compared with predicted micromotions by Finite Element Analysis

  12. Systemic dystrophic alterations of skeleton

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kishkovskij, A.N.; Elashov, Yu.G.

    1984-01-01

    A roentgenologic picture of dystrophic alterations of bones following hard, acute and chronic infections diseases, distinct disorders of vitanium balance, diseases of endocrine system, disorder of metabolism and diet, long-term exogenous intoxications including medicinal is given. Distinct dystrophic disorders are characterized both by quantitative and qualitative deviations in physiological change of bones

  13. Safety concerning the alteration in fuel material usage (new installation of the uranium enrichment pilot plant) at Ningyo Pass Mine of Power Reactor and Nuclear Fuel Development Corporation

    International Nuclear Information System (INIS)

    1978-01-01

    A report of the Committee on Examination of Nuclear Fuel Safety was presented to the Atomic Energy Commission of Japan, which is concerned with the safety in the alteration of fuel material usage (new installation of the uranium enrichment pilot plant) at the Ningyo Pass Mine. Its safety was confirmed. The alteration, i.e. installation of the uranium enrichment pilot plant, is as follows. Intended for the overall test of centrifugal uranium enrichment technology, the pilot plant includes a two-storied main building of about 9,000 m 2 floor space, containing centrifuges, UF 6 equipment, etc., a uranium storage of about 1,000 m 2 floor space, and a waste water treatment facility, two-storied with about 300 m 2 floor space. The contents of the examination are safety of the facilities, criticality control, radiation control, waste treatment, and effects of accidents on the surrounding environment. (Mori, K

  14. Analysis of bone mineral density of human bones for strength ...

    Indian Academy of Sciences (India)

    Different types of bone strength are required for various ... To statically analyse various methods to find BMD and related material ... bone study for research purpose. ..... and Dagoberto Vela Arvizo 2007 A qualitative stress analysis of a cross ...

  15. Method of altering the effective bulk density of solid material and the resulting product: hollow polymeric particles

    International Nuclear Information System (INIS)

    Kool, L.B.; Nolen, R.L.; Solomon, D.E.

    1981-01-01

    Hollow spherical particles are made by spraying a mixture of powdered solid material with a solution of a film-forming polymer in a solvent therefor into a heated chamber where the solvent evaporates. The powder is thereby captured in the wall of the hollow polymer particles formed. Such particles are used to form a suspension in a fluid material. The hollow particles are of such size and wall thickness, in relation to the bulk density of the powdered solid material, that the bulk density of each hollow spherical particle is commensurate with the density of the fluid material. The particles thereby remain in suspension over a substantial period of time with little or no agitation of the fluid. (author)

  16. EFFECT OF INFLIXIMAB ON DYNAMICS OF FUNCTIONAL CLASS AND RADIOLOGICAL SIGN OF BONE AND CARTILAGINOUS TISSUES ALTERATION OF JOINTS IN PATIENTS WITH DIFFERENT TYPES OF JUVENILE ARTHRITIS

    Directory of Open Access Journals (Sweden)

    E.I. Alexeeva

    2008-01-01

    Full Text Available An objective of this trial was evaluation of effect of treatment with blocker of tumor necrosis factor infliximab on dynamics of functional class and radiological changes of bone and cartilaginous tissue of joints in children with different clinical types of juvenile arthritis (JA. Infliximab was used according to standard scheme on 0, 2, 6 and then every 8 week by intravenous infusion. Mean single dose of infliximab was 6,8 ± 2,3 mg/kg. All children were treated with immunosuppressive agents (ciclosporin in 6% of patients, methotrexate in 60%, ciclosporin combined with methotrexate — 20%, ciclosporin with leflunomide — 5%, leflunomide with methotreate — 4% combined with anti cytokine treatment. 7 children were treated with oral glucocorticoids in mean dose 0,37 mg/kg daily. disorders in joint function and structural changes of joints of different severity (radiological sign were discovered in all patients before starting of treatment with infliximab. Duration of observation was 6 week — 2 years. Authors made a conclusion that treatment with infliximab prevents progressing of bone and cartilaginous destruction in all types of AJ, not depending on intensity of its clinical activity. This medication provides for full functional recovery of joints and elimination of features of disablement in patients with good clinical activity.Key words: children, juvenile arthritis, infliximab, treatment.

  17. Sharp and blunt force trauma concealment by thermal alteration in homicides: an in-vitro experiment for methodology and protocol development in forensic anthropological analysis of burnt bones

    OpenAIRE

    Macoveciuc, I; Marquez-Grant, N; Horsfall, I; Zioupos, P

    2017-01-01

    Burning of human remains is one method used by perpetrators to conceal fatal trauma and expert opinions regarding the degree of skeletal evidence concealment are often disparate. This experiment aimed to reduce this incongruence in forensic anthropological interpretation of burned human remains and implicitly contribute to the development of research methodologies sufficiently robust to withstand forensic scrutiny in the courtroom. We have tested the influence of thermal alteration on pre-exi...

  18. 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.

  19. In Vitro Expansion of Bone Marrow Derived Mesenchymal Stem Cells Alters DNA Double Strand Break Repair of Etoposide Induced DNA Damage.

    Science.gov (United States)

    Hare, Ian; Gencheva, Marieta; Evans, Rebecca; Fortney, James; Piktel, Debbie; Vos, Jeffrey A; Howell, David; Gibson, Laura F

    2016-01-01

    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.

  20. Alterations in bone marrow and blood mononuclear cell polyamine and methylglyoxal bis(guanylhydrazone) levels: phase I evaluation of alpha-difluoromethylornithine and methylglyoxal bis(guanylhydrazone) treatment of human hematological malignancies.

    Science.gov (United States)

    Maddox, A M; Freireich, E J; Keating, M J; Haddox, M K

    1988-03-01

    Nine patients with hematological malignancies were treated with difluoromethylornithine and methylglyoxal bis(guanylhydrazone). The number of circulating blast cells decreased in all of the patients treated with DFMO and MGBG for longer than 1 wk. Morphological evidence of myeloid maturation was evident in four patients with leukemia and the circulating M Protein decreased in one patient with multiple myeloma. The polyamine content of the mononuclear cells in both the peripheral blood and bone marrow was transiently increased after the initial MGBG dose. During administration of DFMO decreases were achieved in the peripheral blood mononuclear cell putrescine levels in 7 patients, spermidine levels in 5 patients, and spermine levels in 4 patients. Alterations in bone marrow mononuclear cell polyamine levels were similar to those which occurred in the peripheral cells. An average of 9 days of DFMO treatment was required to lower mononuclear cell polyamine levels. Three of the 4 evaluable patients receiving multiple MGBG doses had an increased mononuclear cell content of MGBG after DFMO pretreatment. Enhancement of cellular MGBG levels was not directly correlated to the degree of cellular polyamine depletion.

  1. 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.

  2. Expansion of the CHR bone code system

    International Nuclear Information System (INIS)

    Farnham, J.E.; Schlenker, R.A.

    1976-01-01

    This report describes the coding system used in the Center for Human Radiobiology (CHR) to identify individual bones and portions of bones of a complete skeletal system. It includes illustrations of various bones and bone segments with their respective code numbers. Codes are also presented for bone groups and for nonbone materials

  3. Evaluation of the in vivo performance of composite aluminum/calcium phosphate (CAPs) as bone reconstruction material; Avaliacao in vivo do desempenho de compositos de alumina/fosfato de calcio (CaPs) como material de reconstrucao ossea

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, P.M.; Lima, M.G.; Costa, A.C. [Universidade Federal de Campina Grande (UFCG), PB (Brazil); Pallone, E.M. [Universidade de Sao Paulo (FZEA/USP), Pirassununga, SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos; Kiminami, R.H. [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil)

    2016-07-01

    This study aims to evaluate the in vivo performance of composite aluminum/calcium phosphate (CAPs) as bone reconstruction material. To this end, mass CAPs relative to the total weight of Al2O3 prepared Al{sub 2}O{sub 3}/CAPs using percentage of 0, 10, 20 and 30% composites. The composites characterized were by X-ray diffraction, scanning electron microscopy with scanning. After implanted in rabbit tibia randomly divided were into two groups, each with nine rabbits, according to the euthanasia period (30 days after surgery). After euthanasia was performed radiographic and histological evaluation of the grafted areas. The results confirm that the compounds Al{sub 2}O{sub 3}/CAPs presented major phase of alumina and the second phase calcium pyrophosphate. Increasing the concentration of CAPs on alumina promoted with a reduction in density and increase in porosity, as well as an increase in grain size and heterogeneity in the microstructure. Upon radiographic examination of the tibiae of the nine (9) rabbits score was observed with grade 3, or similar radiopacity presented by the remaining cortical bone. It shown was that the tibiae of rabbits with the implant showed the presence of foreign material (composite), well delimited with bone formation and bone proliferation around the implants. At the point where the composite in 30 days' time of sacrifice, there was no observable sign of infection was established, since there were observed no cellular infiltration, no rejection of the implant, concluding that the biocompatible composite was studied. (author)

  4. The use of an ion-beam source to alter the surface morphology of biological implant materials

    Science.gov (United States)

    Weigand, A. J.

    1978-01-01

    An electron-bombardment ion-thruster was used as a neutralized-ion-beam sputtering source to texture the surfaces of biological implant materials. The materials investigated included 316 stainless steel; titanium-6% aluminum, 4% vanadium; cobalt-20% chromium, 15% tungsten; cobalt-35% nickel, 20% chromium, 10% molybdenum; polytetrafluoroethylene; polyoxymethylene; silicone and polyurethane copolymer; 32%-carbon-impregnated polyolefin; segmented polyurethane; silicone rubber; and alumina. Scanning electron microscopy was used to determine surface morphology changes of all materials after ion-texturing. Electron spectroscopy for chemical analysis was used to determine the effects of ion-texturing on the surface chemical composition of some polymers. Liquid contact angle data were obtained for ion-textured and untextured polymer samples. Results of tensile and fatigue tests of ion-textured metal alloys are presented. Preliminary data of tissue response to ion-textured surfaces of some metals, polytetrafluoroethylene, alumina, and segmented polyurethane have been obtained.

  5. Thermoplastic starch/ethylene vinyl alcohol/forsterite nanocomposite as a candidate material for bone tissue engineering

    International Nuclear Information System (INIS)

    Mahdieh, Zahra; Bagheri, Reza; Eslami, Masoud; Amiri, Mohammad; Shokrgozar, Mohammad Ali; Mehrjoo, Morteza

    2016-01-01

    Recently, biodegradable polymers such as starch based blends have been well renowned in the biomedical field. Studies have considered them suitable for bone scaffolds, bone cements, tissue engineering scaffolds, drug delivery systems and hydrogels. The aim of this study was to synthesize nanocomposite biomaterial consisting a blend of thermoplastic starch and ethylene vinyl alcohol as the polymer matrix, and nano-structured forsterite as the ceramic reinforcing phase for bone tissue engineering applications. Furthermore, vitamin E was applied as a thermal stabilizer during melt compounding. Extrusion and injection molding were incorporated for melt blending and shaping of samples, respectively. With blending thermoplastic starch and ethylene vinyl alcohol, some properties of thermoplastic starch such as degradation rate and water absorption were modified. In addition, using nanoforsterite as the ceramic reinforcing phase resulted in the improvement of mechanical and biological traits. The addition of nanoforsterite decreased the weight loss of the thermoplastic starch and ethylene vinyl alcohol blend in simulated body fluid. Moreover, this addition modified the pH in the MTT (methyl thiazolyl tetrazolium) assay and stimulated the cell proliferation. Cell adhesion assays indicated a favorable interaction between cells and the biomaterial. The proposed nanocomposite has appropriate biocompatibility, as well as mechanical properties in order to be used in bone tissue engineering. - Highlights: • A biodegradable nanocomposite is proposed for orthopedic applications. • Vitamin E is used as an antioxidant to prevent the thermomechanical degradations. • Nanoforsterite reduced the composite degradation rate in the simulated body fluid. • Nanoforsterite modified pH in MTT assay and stimulated cell proliferation.

  6. Thermoplastic starch/ethylene vinyl alcohol/forsterite nanocomposite as a candidate material for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Mahdieh, Zahra [Polymeric Materials Research Group (PMRG), Department of Materials Science and Engineering, Sharif University of Technology, Tehran, P.O. Box 11155-9466 (Iran, Islamic Republic of); Bagheri, Reza, E-mail: rezabagh@sharif.edu [Polymeric Materials Research Group (PMRG), Department of Materials Science and Engineering, Sharif University of Technology, Tehran, P.O. Box 11155-9466 (Iran, Islamic Republic of); Eslami, Masoud; Amiri, Mohammad [Polymeric Materials Research Group (PMRG), Department of Materials Science and Engineering, Sharif University of Technology, Tehran, P.O. Box 11155-9466 (Iran, Islamic Republic of); Shokrgozar, Mohammad Ali; Mehrjoo, Morteza [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of)

    2016-12-01

    Recently, biodegradable polymers such as starch based blends have been well renowned in the biomedical field. Studies have considered them suitable for bone scaffolds, bone cements, tissue engineering scaffolds, drug delivery systems and hydrogels. The aim of this study was to synthesize nanocomposite biomaterial consisting a blend of thermoplastic starch and ethylene vinyl alcohol as the polymer matrix, and nano-structured forsterite as the ceramic reinforcing phase for bone tissue engineering applications. Furthermore, vitamin E was applied as a thermal stabilizer during melt compounding. Extrusion and injection molding were incorporated for melt blending and shaping of samples, respectively. With blending thermoplastic starch and ethylene vinyl alcohol, some properties of thermoplastic starch such as degradation rate and water absorption were modified. In addition, using nanoforsterite as the ceramic reinforcing phase resulted in the improvement of mechanical and biological traits. The addition of nanoforsterite decreased the weight loss of the thermoplastic starch and ethylene vinyl alcohol blend in simulated body fluid. Moreover, this addition modified the pH in the MTT (methyl thiazolyl tetrazolium) assay and stimulated the cell proliferation. Cell adhesion assays indicated a favorable interaction between cells and the biomaterial. The proposed nanocomposite has appropriate biocompatibility, as well as mechanical properties in order to be used in bone tissue engineering. - Highlights: • A biodegradable nanocomposite is proposed for orthopedic applications. • Vitamin E is used as an antioxidant to prevent the thermomechanical degradations. • Nanoforsterite reduced the composite degradation rate in the simulated body fluid. • Nanoforsterite modified pH in MTT assay and stimulated cell proliferation.

  7. BONES WITH BIOCERAMICS

    Directory of Open Access Journals (Sweden)

    Wijianto Wijianto

    2017-01-01

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

  8. 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.

  9. DON-induced changes in bone homeostasis in mink dams

    Directory of Open Access Journals (Sweden)

    Tomaszewska Ewa

    2017-09-01

    Full Text Available Introduction: The aim of the study was to investigate the mechanical and geometric properties as well as bone tissue and mineral density of long bones in mink dams exposed to deoxynivalenol (DON since one day after mating, throughout gestation (ca. 46 d and lactation to pelt harvesting. Material and Methods: Thirty clinically healthy multiparous minks (Neovison vison of the standard dark brown type were used. After the mating, the minks were randomly assigned into two equal groups: nontreated control group and DON group fed wheat contaminated naturally with DON at a concentration of 1.1 mg·kg-1 of feed. Results: The final body weight and weight and length of the femur did not differ between the groups. However, DON contamination decreased mechanical endurance of the femur. Furthermore, DON reduced the mean relative wall thickness and vertical wall thickness of the femur, while vertical cortical index, midshaft volume, and cross-sectional moment of inertia increased. Finally, DON contamination did not alter bone tissue density, bone mineral density, or bone mineral content, but decreased the values of all investigated structural and material properties. Conclusion: DON at applied concentration probably intensified the process of endosteal resorption, which was the main reason for bone wall thinning and the weakening of the whole bone.

  10. Commercially pure titanium (cp-Ti) versus titanium alloy (Ti6Al4V) materials as bone anchored implants - Is one truly better than the other?

    Science.gov (United States)

    Shah, Furqan A; Trobos, Margarita; Thomsen, Peter; Palmquist, Anders

    2016-05-01

    Commercially pure titanium (cp-Ti) and titanium alloys (typically Ti6Al4V) display excellent corrosion resistance and biocompatibility. Although the chemical composition and topography are considered important, the mechanical properties of the material and the loading conditions in the host have, conventionally, influenced material selection for different clinical applications: predominantly Ti6Al4V in orthopaedics while cp-Ti in dentistry. This paper attempts to address three important questions: (i) To what extent do the surface properties differ when cp-Ti and Ti6Al4V materials are manufactured with the same processing technique?, (ii) Does bone tissue respond differently to the two materials, and (iii) Do bacteria responsible for causing biomaterial-associated infections respond differently to the two materials? It is concluded that: (i) Machined cp-Ti and Ti6Al4V exhibit similar surface morphology, topography, phase composition and chemistry, (ii) Under experimental conditions, cp-Ti and Ti6Al4V demonstrate similar osseointegration and biomechanical anchorage, and (iii) Experiments in vitro fail to disclose differences between cp-Ti and Ti6Al4V to harbour Staphylococcus epidermidis growth. No clinical comparative studies exist which could determine if long-term, clinical differences exist between the two types of bulk materials. It is debatable whether cp-Ti or Ti6Al4V exhibit superiority over the other, and further comparative studies, particularly in a clinical setting, are required. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Relationships between in vivo microdamage and the remarkable regional material and strain heterogeneity of cortical bone of adult deer, elk, sheep and horse calcanei

    Science.gov (United States)

    Skedros, John G; Sybrowsky, Christian L; Anderson, Wm Erick; Chow, Frank

    2011-01-01

    Natural loading of the calcanei of deer, elk, sheep and horses produces marked regional differences in prevalent/predominant strain modes: compression in the dorsal cortex, shear in medial–lateral cortices, and tension/shear in the plantar cortex. This consistent non-uniform strain distribution is useful for investigating mechanisms that mediate the development of the remarkable regional material variations of these bones (e.g. collagen orientation, mineralization, remodeling rates and secondary osteon morphotypes, size and population density). Regional differences in strain-mode-specific microdamage prevalence and/or morphology might evoke and sustain the remodeling that produces this material heterogeneity in accordance with local strain characteristics. Adult calcanei from 11 animals of each species (deer, elk, sheep and horses) were transversely sectioned and examined using light and confocal microscopy. With light microscopy, 20 linear microcracks were identified (deer: 10; elk: six; horse: four; sheep: none), and with confocal microscopy substantially more microdamage with typically non-linear morphology was identified (deer: 45; elk: 24; horse: 15; sheep: none). No clear regional patterns of strain-mode-specific microdamage were found in the three species with microdamage. In these species, the highest overall concentrations occurred in the plantar cortex. This might reflect increased susceptibility of microdamage in habitual tension/shear. Absence of detectable microdamage in sheep calcanei may represent the (presumably) relatively greater physical activity of deer, elk and horses. Absence of differences in microdamage prevalence/morphology between dorsal, medial and lateral cortices of these bones, and the general absence of spatial patterns of strain-mode-specific microdamage, might reflect the prior emergence of non-uniform osteon-mediated adaptations that reduce deleterious concentrations of microdamage by the adult stage of bone development. PMID

  12. Multiscale Modeling of Bone

    Science.gov (United States)

    2014-12-01

    is an ordered array of bone fibers in a matrix material [1]. It is the dominant form of bone and closely resembles a layered fiber - reinforced ...mineral [3], [14]. These fibers are not independent structures, but exist only within the complex lamellar bone [13], similar to a fiber reinforced ...accuracy of this method. What this model does not provide is the transverse properties or a Poisson ’ s ratio for TC. Thus, we must assume that

  13. 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 <3) formation environment [4]. Jarosite and other sulfate minerals, including kieserite, gypsum, and alunite have also been identified in several locations in orbital remote sensing data from the MEx OMEGA and MRO CRISM instruments [e.g. 5-8]. Acid sulfate weathering of basaltic materials is an obvious pathway for formation of sulfate-bearing phases on Mars [e.g. 4, 9, 10]. In order to constrain acid-sulfate pathways on Mars, we are studying the mineralogical and chemical manifestations of acid-sulfate alteration of basaltic compositions in terrestrial environments. We have previously shown that acidsulfate alteration of tephra under hydrothermal conditions on the Puu Poliahu cone (summit region of Mauna Kea 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

  14. An investigation of the mineral in ductile and brittle cortical mouse bone.

    Science.gov (United States)

    Rodriguez-Florez, Naiara; Garcia-Tunon, Esther; Mukadam, Quresh; Saiz, Eduardo; Oldknow, Karla J; Farquharson, Colin; Millán, José Luis; Boyde, Alan; Shefelbine, Sandra J

    2015-05-01

    Bone is a strong and tough material composed of apatite mineral, organic matter, and water. Changes in composition and organization of these building blocks affect bone's mechanical integrity. Skeletal disorders often affect bone's mineral phase, either by variations in the collagen or directly altering mineralization. The aim of the current study was to explore the differences in the mineral of brittle and ductile cortical bone at the mineral (nm) and tissue (µm) levels using two mouse phenotypes. Osteogenesis imperfecta model, oim(-/-) , mice have a defect in the collagen, which leads to brittle bone; PHOSPHO1 mutants, Phospho1(-/-) , have ductile bone resulting from altered mineralization. Oim(-/-) and Phospho1(-/-) were compared with their respective wild-type controls. Femora were defatted and ground to powder to measure average mineral crystal size using X-ray diffraction (XRD) and to monitor the bulk mineral to matrix ratio via thermogravimetric analysis (TGA). XRD scans were run after TGA for phase identification to assess the fractions of hydroxyapatite and β-tricalcium phosphate. Tibiae were embedded to measure elastic properties with nanoindentation and the extent of mineralization with backscattered electron microscopy (BSE SEM). Results revealed that although both pathology models had extremely different whole-bone mechanics, they both had smaller apatite crystals, lower bulk mineral to matrix ratio, and showed more thermal conversion to β-tricalcium phosphate than their wild types, indicating deviations from stoichiometric hydroxyapatite in the original mineral. In contrast, the degree of mineralization of bone matrix was different for each strain: brittle oim(-/-) were hypermineralized, whereas ductile Phospho1(-/-) were hypomineralized. Despite differences in the mineralization, nanoscale alterations in the mineral were associated with reduced tissue elastic moduli in both pathologies. Results indicated that alterations from normal crystal size

  15. 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.

  16. Bone changes in leprosy

    International Nuclear Information System (INIS)

    Mende, B.; Stein, G.; Kreysel, H.W.

    1985-01-01

    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. (orig.) [de

  17. Bone Geometry as a Predictor of Tissue Fragility and Stress Fracture Risk

    National Research Council Canada - National Science Library

    Jepsen, Karl

    2003-01-01

    ... and bone quality, such that slender bones are associated with more damageable bone tissue. We postulate that a similar reciprocal relationship between bone mass and bone material properties exists in the human skeleton...

  18. Bone Geometry as a Predictor of Tissue Fragility and Stress Fracture Risk

    National Research Council Canada - National Science Library

    Jepsen, Karl J

    2004-01-01

    ... and bone quality, such that slender bones are associated with more damageable bone tissue. We postulate that a similar reciprocal relationship between bone mass and bone material properties exists in the human skeleton...

  19. Bone Geometry as a Predictor of Tissue Fragility and Stress Fracture Risk

    National Research Council Canada - National Science Library

    Jepsen, Karl J

    2006-01-01

    ... and bone quality, such that slender bones are associated with more damageable bone tissue. We postulate that a similar reciprocal relationship between bone mass and bone material properties exists in the human skeleton...

  20. Bone Geometry as a Predictor of Tissue Fragility and Stress Fracture Risk

    National Research Council Canada - National Science Library

    Jepsen, Karl

    2002-01-01

    ... and bone quality, such that slender bones are associated with more damageable bone tissue. We postulate that a similar reciprocal relationship between bone mass and bone material properties exists in the human skeleton...

  1. Animal Bone Remnants from Trench CLXII of the Bolgar City Site: Some New Methods of Archaeozoological Materials Processing and Evaluation

    OpenAIRE

    Yavorskaya Lilia V.

    2012-01-01

    It is for the first time in the study of animal bone remnants from the Bolgar city site that modern techniques have been applied, which have made it possible to solve archaeological and historical problems rather than purely biological ones. A detailed description of the work process based on these techniques and of the results obtained is offered. In particular, it has been found out that the cattle intended for slaughter in Bolgar had not been bred within the city limits but rather supplied...

  2. Competition between clonal plasma cells and normal cells for potentially overlapping bone marrow niches is associated with a progressively altered cellular distribution in MGUS vs myeloma.

    Science.gov (United States)

    Paiva, B; Pérez-Andrés, M; Vídriales, M-B; Almeida, J; de las Heras, N; Mateos, M-V; López-Corral, L; Gutiérrez, N C; Blanco, J; Oriol, A; Hernández, M T; de Arriba, F; de Coca, A G; Terol, M-J; de la Rubia, J; González, Y; Martín, A; Sureda, A; Schmidt-Hieber, M; Schmitz, A; Johnsen, H E; Lahuerta, J-J; Bladé, J; San-Miguel, J F; Orfao, A

    2011-04-01

    Disappearance of normal bone marrow (BM) plasma cells (PC) predicts malignant transformation of monoclonal gammopathy of undetermined significance (MGUS) and smoldering myeloma (SMM) into symptomatic multiple myeloma (MM). The homing, behavior and survival of normal PC, but also CD34(+) hematopoietic stem cells (HSC), B-cell precursors, and clonal PC largely depends on their interaction with stromal cell-derived factor-1 (SDF-1) expressing, potentially overlapping BM stromal cell niches. Here, we investigate the distribution, phenotypic characteristics and competitive migration capacity of these cell populations in patients with MGUS, SMM and MM vs healthy adults (HA) aged >60 years. Our results show that BM and peripheral blood (PB) clonal PC progressively increase from MGUS to MM, the latter showing a slightly more immature immunophenotype. Of note, such increased number of clonal PC is associated with progressive depletion of normal PC, B-cell precursors and CD34(+) HSC in the BM, also with a parallel increase in PB. In an ex vivo model, normal PC, B-cell precursors and CD34(+) HSC from MGUS and SMM, but not MM patients, were able to abrogate the migration of clonal PC into serial concentrations of SDF-1. Overall, our results show that progressive competition and replacement of normal BM cells by clonal PC is associated with more advanced disease in patients with MGUS, SMM and MM.

  3. Kinetics of sup(99m)Tc-pyrophosphate in comparison with 85Sr in acutely and chronically altered soft part and bone regions

    International Nuclear Information System (INIS)

    Buell, U.; Balser, D.; Boehner-Schoberth, I.; Frey, K.W.; Muenchen Univ.; Muenchen Univ.

    1974-01-01

    Summarizing our findings, we can state that *Tc-pyrophosphate concentrates in acutely inflammated soft tissue and some malignant soft-tissue tumors. In comparison with *Sr, Tc-pyrophosphate concentration is relatively higher but absolute concentration does not exceed the Sr concentration up to 3 hours post injection. 24 hours after injection we found a significantly higher *Tc-PyP concentration in all soft tissues, whether inflammated or not, pure muscle excluded. These findings correlate well with the collagen contents in the tissues, which is underlined by the fact that the highest *Tc-PyP concentration in normal soft tissue examined has been found in the patellar tendon. In rheumatic arthritis the positive joint scan with *Tc-PyP could be due to the damaged soft tissue only, even when bone destruction is evident. In humans bearing osteoarthritis of the hip joint we found a threefold higher concentration of *Tc-PyP in the joint capsule compared with the muscle. 85 Sr concentration was twice as high. (orig.) [de

  4. Smectite alteration

    International Nuclear Information System (INIS)

    Anderson, D.M.

    1984-11-01

    This report contains the proceedings of a second workshop in Washington DC December 8-9, 1983 on the alteration of smectites intended for use as buffer materials in the long-term containment of nuclear wastes. It includes extended summaries of all presentations and a transcript of the detailed scientific discussion. The discussions centered on three main questions: What is the prerequisite for and what is the precise mechanism by which smectite clays may be altered to illite. What are likly sources of potassium with respect to the KBS project. Is it likely that the conversion of smectite to illite will be of importance in the 10 5 to the 10 6 year time frame. The workshop was convened to review considerations and conclusions in connection to these questions and also to broaden the discussion to consider the use of smectite clays as buffer materials for similar applications in different geographical and geological settings. SKBF/KBS technical report 83-03 contains the proceedings from the first workshop on these matters that was held at the State University of New York, Buffalo May 26-27, 1982. (Author)

  5. Bone scintigraphy for horses

    International Nuclear Information System (INIS)

    Jahn, Werner

    2010-01-01

    Scintigraphy (bone scan) is being used approximately since 1980 in the horse under general anaesthesia. With the construction of custom-made overhead gantries for gamma-cameras scintigraphy found widespread entry in big equine referral hospitals for bone-scanning of the standing horse. Indications for the use of a bone scan in the horse are inflammatory alterations in the locomotor apparatus. It is primarily used for diagnosis of lameness of unknown origin, suspect of stress fracture or hairline fracture and for horses with bad riding comfort with suspected painful lesions in the spine. (orig.)

  6. 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

    International Nuclear Information System (INIS)

    Cheng, Kang; Rai, Partab; Lan, Xiqian; Plagov, Andrei; Malhotra, Ashwani; Gupta, Sanjeev; Singhal, Pravin C.

    2013-01-01

    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

  7. 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.

  8. 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)

    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. PMID:26928288

  9. 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.

  10. 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.

  11. Materials for heavy current accelerators and their alteration under scattered protons resulted from acceleration and secondary radiations

    International Nuclear Information System (INIS)

    L'vov, A.N.; Sidorenko, I.S.; Khizhnyak, N.A.; Shilyaev, B.A.; Yamnitskij, V.A.

    1983-01-01

    Changes of macroscopic properties of materials for new generation accelerators during irradiation by spill protons and secondary radiations have been analyzed. It is shown, that the change in properties is a result of many interrelated processes: nuclear ones, in which initially knocked out atoms (IKA) and products of nuclear reactions (especially helium and hydrogen) are formed, atomic ones consisting in the development of cascade collisions induced by IKA and resulting in the formation of initial regions of point defects accumulation; structural ones, resulting in the formation ssociations of defects, pores, dislocations and in the processes of creep, swelling, embrittlement etc. Each process is deccribed by a model and is realized by a computer code. The full program complex is written in the FORTRAN and ALGOL (GDR) for the BEhSM-6 and EC-1040 computers. Total number of standard code library exceeds 20 thousand operators, the memory size of base data is about 10 megabyte

  12. Hypermineralization and High Osteocyte Lacunar Density in Osteogenesis Imperfecta Type V Bone Indicate Exuberant Primary Bone Formation.

    Science.gov (United States)

    Blouin, Stéphane; Fratzl-Zelman, Nadja; Glorieux, Francis H; Roschger, Paul; Klaushofer, Klaus; Marini, Joan C; Rauch, Frank

    2017-09-01

    In contrast to "classical" forms of osteogenesis imperfecta (OI) types I to IV, caused by a mutation in COL1A1/A2, OI type V is due to a gain-of-function mutation in the IFITM5 gene, encoding the interferon-induced transmembrane protein 5, or bone-restricted interferon-inducible transmembrane (IFITM)-like protein (BRIL). Its phenotype distinctly differs from OI types I to IV by absence of blue sclerae and dentinogenesis imperfecta, by the occurrence of ossification disorders such as hyperplastic callus and forearm interosseous membrane ossification. Little is known about the impact of the mutation on bone tissue/material level in untreated and bisphosphonate-treated patients. Therefore, investigations of transiliac bone biopsy samples from a cohort of OI type V children (n = 15, 8.7 ± 4 years old) untreated at baseline and a subset (n = 8) after pamidronate treatment (2.6 years in average) were performed. Quantitative backscattered electron imaging (qBEI) was used to determine bone mineralization density distribution (BMDD) as well as osteocyte lacunar density. The BMDD of type V OI bone was distinctly shifted toward a higher degree of mineralization. The most frequently occurring calcium concentration (CaPeak) in cortical (Ct) and cancellous (Cn) bone was markedly increased (+11.5%, +10.4%, respectively, p < 0.0001) compared to healthy reference values. Treatment with pamidronate resulted in only a slight enhancement of mineralization. The osteocyte lacunar density derived from sectioned bone area was elevated in OI type V Ct and Cn bone (+171%, p < 0.0001; +183.3%, p < 0.01; respectively) versus controls. The high osteocyte density was associated with an overall immature primary bone structure ("mesh-like") as visualized by polarized light microscopy. In summary, the bone material from OI type V patients is hypermineralized, similar to other forms of OI. The elevated osteocyte lacunar density in connection with lack of regular bone

  13. MR imaging of the bone marrow using short TI IR, 1. Normal and pathological intensity distribution of the bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Ishizaka, Hiroshi; Kurihara, Mikiko; Tomioka, Kuniaki; Kobayashi, Kanako; Sato, Noriko; Nagai, Teruo; Heshiki, Atsuko; Amanuma, Makoto; Mizuno, Hitomi.

    1989-02-01

    Normal vertebral bone marrow intensity distribution and its alteration in various anemias were evaluated on short TI IR sequences. Material consists of 73 individuals, 48 normals and 25 anemic patients excluding neoplastic conditions. All normal and reactive hypercellular bone marrow revealed characteristic intensity distribution; marginal high intensity and central low intensity, corresponding well to normal distribution of red and yellow marrows and their physiological or reactive conversion between red and yellow marrows. Aplastic anemia did not reveal normal intensity distribution, presumably due to autonomous condition.

  14. Effect of Poly(Vinyl Alcohol) Addition on the Properties of Hydrothermal Derived Calcium Phosphate Cement for Bone Filling Materials

    Science.gov (United States)

    Razali, N. N.; Sopyan, I.; Mel, M.; Salleh, H. M.; Rahman, M. M.; Singh, R.

    2017-06-01

    The effect of addition of poly(vinyl alcohol) on hydrothermal derived calcium phosphate cement has been studied. The precursors used to prepare the cement were calcium oxide (CaO) and ammonium dihydrogen phosphate (NH4H2PO4); the reaction was conducted in water at 80-100°C. To improve properties of CPC, poly(vinyl alcohol) (PVA) of 1wt% and 2wt% was added to the liquid phase of CPC and the results were compared to CPC without PVA addition. The addition of PVA was proved to bring remarkable effects on cohesion, setting time and mechanical strength of CPC which make it suitable physically for injectable bone filler applications.

  15. Chemical Makeup of Microdamaged Bone Differs from Undamaged Bone

    International Nuclear Information System (INIS)

    Ruppel, M.; Burr, D.; Miller, L.

    2006-01-01

    Microdamage naturally occurs in bone tissue as a result of cyclic loading placed on the body from normal daily activities. While it is usually repaired through the bone turnover process, accumulation of microdamage may result in reduced bone quality and increased fracture risk. It is unclear whether certain areas of bone are more susceptible to microdamage than others due to compositional differences. This study examines whether areas of microdamaged bone are chemically different than undamaged areas of bone. Bone samples (L3 vertebrae) were harvested from 15 dogs. Samples were stained with basic fuchsin, embedded in poly-methylmethacrylate, and cut into 5-(micro)m-thick sections. Fuchsin staining was used to identify regions of microdamage, and synchrotron infrared microspectroscopic imaging was used to determine the local bone composition. Results showed that microdamaged areas of bone were chemically different than the surrounding undamaged areas. Specifically, the mineral stoichiometry was altered in microdamaged bone, where the carbonate/protein ratio and carbonate/phosphate ratio were significantly lower in areas of microdamage, and the acid phosphate content was higher. No differences were observed in tissue mineralization (phosphate/protein ratio) or crystallinity between the microdamaged and undamaged bone, indicating that the microdamaged regions of bone were not over-mineralized. The collagen cross-linking structure was also significantly different in microdamaged areas of bone, consistent with ruptured cross-links and reduced fracture resistance. All differences in composition had well-defined boundaries in the microcrack region, strongly suggesting that they occurred after microcrack formation. Even so, because microdamage results in an altered bone composition, an accumulation of microdamage might result in a long-term reduction in bone quality

  16. Early MRI Detection and Closed Bone Graft Epiphysiodesis May Alter the Course of Avascular Necrosis Following Unstable Slipped Capital Femoral Epiphysis.

    Science.gov (United States)

    Napora, Joshua K; Gilmore, Allison; Son-Hing, Jochen P; Grimberg, Dominic C; Thompson, George H; Liu, Raymond W

    2018-04-01

    Unstable slipped capital femoral epiphysis (SCFE) has an increased incidence of avascular necrosis (AVN). Early identification and surgical intervention for AVN may help preserve the femoral head. We retrospectively reviewed 48 patients (50 hips) with unstable SCFE managed between 2000 and 2014. AVN was diagnosed based on 2 different postoperative protocols. Seventeen patients (17 hips) had a scheduled magnetic resonance imaging (MRI) between 1 and 6 months from initial surgery, and the remaining 31 patients (33 hips) were evaluated by plain radiographs alone. If AVN was diagnosed, we offered core decompression and closed bone graft epiphysiodesis (CBGE) to mitigate its affects. At final follow-up, we assessed progression of AVN using the Steinberg classification. Overall 13 hips (26%) with unstable SCFEs developed AVN. MRI revealed AVN in 7 of 17 hips (41%) at a mean of 2.5 months postoperatively (range, 1.0 to 5.2 mo). Six hips diagnosed by MRI received surgical intervention (4 CBGE, 1 free vascularized fibula graft, and 1 repinning due to screw cutout) at a mean of 4.1 months (range, 1.3 to 7.2 mo) postoperatively. None of the 4 patients treated with CBGE within 2 months postoperatively progressed to stage IVC AVN. The 2 patients treated after 4 months postoperatively both progressed to stage VC AVN.Plain radiographs demonstrated AVN in 6 of 33 hips (18%) at a mean of 6.8 months postoperatively (range, 2.1 to 21.1 mo). One patient diagnosed with stage IVB AVN at 2.4 months had screw cutout and received CBGE at 2.5 months from initial pinning. The remaining 5 were not offered surgical intervention. Five of the 6 radiographically diagnosed AVN, including the 1 treated with CBGE, progressed to stage IVC AVN or greater. Although all patients with positive MRI scans developed radiographic AVN, none of the 4 patients treated with CBGE within 2 months after pinning developed grade IVC or greater AVN. Early MRI detection and CBGE may mitigate the effects of AVN after

  17. 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 ...

  18. 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 ...

  19. A multifunctional bioactive material that stimulates osteogenesis and promotes the vascularization bone marrow stem cells and their resistance to bacterial infection.

    Directory of Open Access Journals (Sweden)

    Chuang Ma

    Full Text Available The main limitation of tissue engineering lies in the inability to stimulate osteogenesis, angiogenesis of stem cells and broad-spectrum antimicrobial activity. However, the development of multifunctional bioactive materials with these capabilities remains a great challenge. In this study, we prepared mesoporous silica nanoparticles encapsulated with silver nanocrystals (AG-MSN with uniform sphere size and mesopores. Platelet-derived growth factor BB (PDGF-BB was effectively loaded in the AG-MSN mesopores (P-AG-MSN. The silicon ions (Si released by P-AG-MSN stimulate osteogenic differentiation of bone marrow stromal cells (BMSC by activating the alkaline phosphatase (ALP activity of bone-related genes and increasing protein (OCN, RUNX2 and OPN expression. Ag+ ions could be slowly released from the interior of the shell, highlighting their durable antibacterial activity. The sustained release of PDGF-BB from P-AG-MSN stimulated the angiogenic differentiation of BMSC, as indicated by the enhanced secretion of vascular endothelial growth factor (VEGF, HIF-1α, HGF and ANG-1 and protein expression. Our results show that P-AG-MSN can clearly promote BMSC osteostimulation and vascularization. This research serves as a preliminary study of the utilization of this multifunctional mixture to fabricate a new active biological scaffold that integrates BMSC osteostimulation, vascularization and bactericidal effects by 3D printing technology.

  20. Connexin 43 Channels are Essential for Normal Bone Structure and Osteocyte Viability

    Science.gov (United States)

    Xu, Huiyun; Gu, Sumin; Riquelme, Manuel A.; Burra, Sirisha; Callaway, Danielle; Cheng, Hongyun; Guda, Teja; Schmitz, James; Fajardo, Roberto J.; Werner, Sherry L.; Zhao, Hong; Shang, Peng; Johnson, Mark L.; Bonewald, Lynda F.; Jiang, Jean X.

    2014-01-01

    Connexin (Cx) 43 serves important roles in bone function and development. Targeted deletion of Cx43 in osteoblasts or osteocytes leads to increased osteocyte apoptosis, osteoclast recruitment, and reduced biomechanical properties. Cx43 forms both gap junction channels and hemichannels, which mediate the communication between adjacent cells or between cell and extracellular environments, respectively. Two transgenic mouse models driven by a DMP1 promoter with the overexpression of dominant negative Cx43 mutants were generated to dissect the functional contribution of Cx43 gap junction channels and hemichannels in osteocytes. The R76W mutant blocks gap junction channel, but not hemichannel function, and the Δ130-136 mutant inhibits activity of both types of channels. Δ130-136 mice showed a significant increase in bone mineral density compared to WT and R76W mice. MicroCT analyses revealed a significant increase in total tissue and bone area in midshaft cortical bone of Δ130-136 mice. The bone marrow cavity was expanded, whereas the cortical thickness was increased and associated with increased bone formation along the periosteal area. However, there is no significant alteration in the structure of trabecular bone. Histologic sections of the midshaft showed increased apoptotic osteocytes in Δ130-136, but not in WT and R76W, mice which correlated with altered biomechanical and estimated bone material properties. Osteoclasts were increased along the endocortical surface in both transgenic mice with a greater effect in Δ130-136 mice which likely contributed to the increased marrow cavity. Interestingly, the overall expression of serum bone formation and resorption markers were higher in R76W mice. These findings suggest that osteocytic Cx43 channels play distinctive roles in the bone; hemichannels play a dominant role in regulating osteocyte survival, endocortical bone resorption and periosteal apposition, and gap junction communication is involved in the process of

  1. 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.)

  2. Nurse’s A-Phase Material Enhance Adhesion, Growth and Differentiation of Human Bone Marrow-Derived Stromal Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Ruben Rabadan-Ros

    2017-03-01

    Full Text Available The purpose of this study was to evaluate the bioactivity and cell response of a well-characterized Nurse’s A-phase (7CaO·P2O5·2SiO2 ceramic and its effect compared to a control (tissue culture polystyrene-TCPS on the adhesion, viability, proliferation, and osteogenic differentiation of ahMSCs in vitro. Cell proliferation (Alamar Blue Assay, Alizarin Red-S (AR-s staining, alkaline phosphatase (ALP activity, osteocalcin (OCN, and collagen I (Col I were evaluated. Also, field emission scanning electron microscopy (FESEM images were acquired in order to visualise the cells and the topography of the material. The proliferation of cells growing in a direct contact with the material was slower at early stages of the study because of the new environmental conditions. However, the entire surface was colonized after 28 days of culture in growth medium (GM. Osteoblastic differentiation markers were significantly enhanced in cells growing on Nurse’s A phase ceramic and cultured with osteogenic medium (OM, probably due to the role of silica to stimulate the differentiation of ahMSCs. Moreover, calcium nodules were formed under the influence of ceramic material. Therefore, it is predicted that Nurse’s A-phase ceramic would present high biocompatibility and osteoinductive properties and would be a good candidate to be used as a biomaterial for bone tissue engineering.

  3. 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.

    2014-01-01

    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 (hBMSCs) was assessed related to adipogenic differentiation. The presence of curcumin significantly reduced silk gelation time and changed the porous morphology of gel matrix, but did not change the formation of silk beta-sheet structure. Based on spectrofluorimetric analysis, curcumin 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 hours incubation in aqueous solution. For hBMSCs cultured on silk films containing more than 0.25 mg/mL curcumin, cell proliferation was inhibited while adipogenesis was significantly promoted based on transcripts as well as oil red O staining. When hBMSCs were cultured in media containing free curcumin, both proliferation and adipogenesis of hBMSCs were inhibited when curcumin concentrations exceeded 5 μM, which is more than 1,000-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 when compared to curcumin in solution. PMID:25132274

  4. The effect of perfusion culture on proliferation and differentiation of human mesenchymal stem cells on biocorrodible bone replacement material

    International Nuclear Information System (INIS)

    Farack, J.; Wolf-Brandstetter, C.; Glorius, S.; Nies, B.; Standke, G.; Quadbeck, P.; Worch, H.; Scharnweber, D.

    2011-01-01

    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 10 (PO 4 ) 6 OH 2 ]) coated foams released 500 μg/g iron per day for Dulbecco's modified eagle medium (DMEM) and 250 μg/g iron per day for McCoys, the unmodified reference 1000 μg/g iron per day for DMEM and 500 μg/g iron per day for McCoys, while no corrosion could be detected on brushite (CaHPO 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.

  5. Effects of exercise prior or during pregnancy in high fat diet fed mice alter bone gene expression of female offspring: An experimental study

    Directory of Open Access Journals (Sweden)

    Abbasali Gaeini

    2017-08-01

    Full Text Available Background: Ovarian hyperstimulation syndrome (OHSS is one of the most important complications of assisted reproduction treatment. Many substances are involved in the regulation of the vascular permeability, which have been concerned to cause OHSS. Vascular endothelial growth factor (VEGF has emerged as one of the main angiogenic factors, which could be responsible for increased vascular permeability. Objective: In this study the association of vascular endothelial growth factor - 460C/T and +405 G/C polymorphisms and susceptibility to ovarian hyperstimulation syndrome was evaluated. Materials and Methods: In this cross sectional study, VEGF gene polymorphisms were amplified by Polymerase chain reaction- Restriction Fragment Length Polymorphism in 75 women with established OHSS (case group and 85 normoresponder (control group which received conventional ovarian stimulation regimen. Results: There was no significant difference in the frequency of -460 C/T polymorphism between cases and controls (p=0.85. The frequency of +405 G/C polymorphism was significantly higher in the OHSS women (p=0.03, OR=2.44; 95% CI=1.23-4.82. Conclusion: In women who developed OHSS, VEGF gene polymorphism +405 could be effective. Two of the polymorphisms -460 C/T and +405 G/C were reported to be associated with increased VEGF basal promoter activity. However, only +405 G/C gene polymorphisms were more frequent in cases than controls

  6. 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

  7. Functionalization of deproteinized bovine bone with a coating-incorporated depot of BMP-2 renders the material efficienctly osteoinductive and suppresses foreign-body reactivity

    NARCIS (Netherlands)

    Wu, G.; Hunziker, E.B.; Zheng, Y.; Wismeijer, D.; Liu, Y.

    2011-01-01

    The repair of critical-sized bony defects remains a challenge in the fields of implantology, maxillofacial surgery and orthopaedics. As an alternative bone-defect filler to autologous bone grafts, deproteinized bovine bone (DBB) is highly osteoconductive and clinically now widely used. However, this

  8. Influence of prosthesis type and material on the stress distribution in bone around implants: A 3-dimensional finite element analysis

    Directory of Open Access Journals (Sweden)

    Gökçe Meriç

    2011-03-01

    Conclusions: Prosthesis design and materials affect the load-transmission mechanism. Although additional experimental and clinical studies are needed, FRC FPDs can be considered a suitable alternative treatment choice for implant-supported prostheses. Within the limitations of the study, the 3-unit FPD supported by 2 implants with a cantilevered extension revealed acceptable stress distributions.

  9. Mechanisms of diabetes mellitus-induced bone fragility.

    Science.gov (United States)

    Napoli, Nicola; Chandran, Manju; Pierroz, Dominique D; Abrahamsen, Bo; Schwartz, Ann V; Ferrari, Serge L

    2017-04-01

    The risk of fragility fractures is increased in patients with either type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM). Although BMD is decreased in T1DM, BMD in T2DM is often normal or even slightly elevated compared with an age-matched control population. However, in both T1DM and T2DM, bone turnover is decreased and the bone material properties and microstructure of bone are altered; the latter particularly so when microvascular complications are present. The pathophysiological mechanisms underlying bone fragility in diabetes mellitus are complex, and include hyperglycaemia, oxidative stress and the accumulation of advanced glycation endproducts that compromise collagen properties, increase marrow adiposity, release inflammatory factors and adipokines from visceral fat, and potentially alter the function of osteocytes. Additional factors including treatment-induced hypoglycaemia, certain antidiabetic medications with a direct effect on bone and mineral metabolism (such as thiazolidinediones), as well as an increased propensity for falls, all contribute to the increased fracture risk in patients with diabetes mellitus.

  10. 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.

  11. 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

    International Nuclear Information System (INIS)

    Altman, S.J.; Tidwell, V.C.; Uchida, M.

    2001-01-01

    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

  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. Biomimetic soluble collagen purified from bones.

    Science.gov (United States)

    Ferreira, Ana Marina; Gentile, Piergiorgio; Sartori, Susanna; Pagliano, Cristina; Cabrele, Chiara; Chiono, Valeria; Ciardelli, Gianluca

    2012-11-01

    Type I collagen has been extensively exploited as a biomaterial for biomedical applications and drug delivery; however, small molecular alterations occurring during the isolation procedure and its interaction with residual bone extracellular matrix molecules or proteins might affect the overall material biocompatibility and performance. The aim of the current work is to study the potential alterations in collagen properties and organization associated with the absence of proteoglycans, which mimic pathological conditions associated with age-related diseases. A new approach for evaluating the effect of proteoglycans on the properties of isolated type I collagen from the bone matrix is described. Additional treatment with guanidine hydrochloride was introduced to remove residual proteoglycans from the collagen matrix. The properties of the isolated collagen with/without guanidine hydrochloride treatment were investigated and compared with a commercial rabbit collagen as control. We demonstrate that the absence of proteoglycans in the isolated type I collagen affects its thermal properties, the extraction into its native structure, and its ability to hydrate and self-assemble into fibers. The fine control and tuning of all these features, linked to the absence of non-collagenous proteins as proteoglycans, offer the possibility of designing new strategies and biomaterials with advanced biomimetic properties aimed at regenerating bone tissue in the case of fragility and/or defects. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Maxillary sinus lift with solely autogenous bone compared to a combination of autogenous bone and growth factors or (solely) bone substitutes. A systematic review : a systematic review

    NARCIS (Netherlands)

    Rickert, D.; Slater, J. J. R. Huddleston; Meijer, H. J. A.; Vissink, A.; Raghoebar, G. M.

    Literature regarding the outcome of maxillary sinus floor elevation to create sufficient bone fraction to enable implant placement was systematically reviewed. Bone fraction and implant survival rate were assessed to determine whether grafting material or applied growth factor affected bone

  15. Biomechanical properties of bone allografts

    International Nuclear Information System (INIS)

    Pelker, R.R.; Friedlaender, G.E.; Markham, T.C.

    1983-01-01

    The biomechanical properties of allograft bone can be altered by the methods chosen for its preservation and storage. These effects are minimal with deep-freezing or low-level radiation. Freeze-drying, however, markedly diminishes the torsional and bending strength of bone allografts but does not deleteriously affect the compressive or tensile strength. Irradiation of bone with more than 3.0 megarad or irradiation combined with freeze-drying appears to cause a significant reduction in breaking strength. These factors should be considered when choosing freeze-dried or irradiated allogeneic bone that will be subjected to significant loads following implantation

  16. Gut microbiome and bone.

    Science.gov (United States)

    Ibáñez, Lidia; Rouleau, Matthieu; Wakkach, Abdelilah; Blin-Wakkach, Claudine

    2018-04-11

    The gut microbiome is now viewed as a tissue that interacts bidirectionally with the gastrointestinal, immune, endocrine and nervous systems, affecting the cellular responses in numerous organs. Evidence is accumulating of gut microbiome involvement in a growing number of pathophysiological processes, many of which are linked to inflammatory responses. More specifically, data acquired over the last decade point to effects of the gut microbiome on bone mass regulation and on the development of bone diseases (such as osteoporosis) and of inflammatory joint diseases characterized by bone loss. Mice lacking a gut microbiome have bone mass alteration that can be reversed by gut recolonization. Changes in the gut microbiome composition have been reported in mice with estrogen-deficiency osteoporosis and have also been found in a few studies in humans. Probiotic therapy decreases bone loss in estrogen-deficient animals. The effect of the gut microbiome on bone tissue involves complex mechanisms including modulation of CD4 + T cell activation, control of osteoclastogenic cytokine production and modifications in hormone levels. This complexity may contribute to explain the discrepancies observed betwwen some studies whose results vary depending on the age, gender, genetic background and treatment duration. Further elucidation of the mechanisms involved is needed. However, the available data hold promise that gut microbiome manipulation may prove of interest in the management of bone diseases. Copyright © 2018 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  17. Materialism.

    Science.gov (United States)

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website. Copyright © 2012 John Wiley & Sons, Ltd.

  18. [Biomaterials in bone repair].

    Science.gov (United States)

    Puska, Mervi; Aho, Allan J; Vallittu, Pekka K

    2013-01-01

    In orthopedics, traumatology, and craniofacial surgery, biomaterials should meet the clinical demands of bone that include shape, size and anatomical location of the defect, as well as the physiological load-bearing stresses. Biomaterials are metals, ceramics, plastics or materials of biological origin. In the treatment of large defects, metallic endoprostheses or bone grafts are employed, whereas ceramics in the case of small defects. Plastics are employed on the artificial joint surfaces, in the treatment of vertebral compression fractures, and as biodegradable screws and plates. Porosity, bioactivity, and identical biomechanics to bone are fundamental for achieving a durable, well-bonded, interface between biomaterial and bone. In the case of severe bone treatments, biomaterials should also imply an option to add biologically active substances.

  19. 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

  20. 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

  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. Exploring gamma radiation effect on exoelectron emission properties of bone

    International Nuclear Information System (INIS)

    Zakaria, M.; Dekhtyar, Y.; Bogucharska, T.; Noskov, V.

    2006-01-01

    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)

  3. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  4. 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.

  5. Nano-TiO2/PEEK bioactive composite as a bone substitute material: in vitro and in vivo studies

    Science.gov (United States)

    Wu, Xiaomian; Liu, Xiaochen; Wei, Jie; Ma, Jian; Deng, Feng; Wei, Shicheng

    2012-01-01

    Background Compared with titanium (Ti) and other metal implant materials, poly(ether-ether ketone) (PEEK) shows outstanding biomechanical properties. A number of studies have also reported attractive bioactivity for nano-TiO2 (n-TiO2). Methods In this study, n-TiO2/PEEK nanocomposites were prepared, taking advantage of the unique properties of both PEEK polymer and n-TiO2. The in vitro and in vivo bioactivity of these nanocomposites was assessed against a PEEK polymer control. The effect of surface morphology or roughness on the bioactivity of the n-TiO2/PEEK nanocomposites was also studied. n-TiO2/PEEK was successfully fabricated and cut into disks for physical and chemical characterization and in vitro studies, and prepared as cylindrical implants for in vivo studies. Their presence on the surface and dispersion in the composites was observed and analyzed by scanning and transmission electron microscopy and X-ray photoelectron spectroscopy. Results Bioactivity evaluation of the nanocomposites revealed that pseudopods of osteoblasts preferred to anchor at areas where n-TiO2 was present on the surface. In a cell attachment test, smooth PEEK showed the lowest optical density value (0.56 ± 0.07) while rough n-TiO2/PEEK exhibited the highest optical density value (1.21 ± 0.34, P PEEK was approximately twice as large as that of PEEK (P PEEK, especially if it has a rough composite surface. A n-TiO2/PEEK composite with a rough surface could be a novel alternative implant material for orthopedic and dental applications. PMID:22419869

  6. Influence of bone morphogenetic protein-2 on the extracellular matrix, material properties, and gene expression of long-term articular chondrocyte cultures: loss of chondrocyte stability.

    Science.gov (United States)

    Krawczak, David A; Westendorf, Jennifer J; Carlson, Cathy S; Lewis, Jack L

    2009-06-01

    The aim of this study was to determine the effects of bone morphogenetic protein-2 (BMP-2) on articular chondrocyte tissues grown as monolayers in vitro for up to 8 weeks. Articular chondrocytes were isolated from New Zealand White rabbits and plated in monolayer cultures. The cultures were supplemented with 100 ng/mL of BMP-2 for up to 8 weeks and the extracellular matrix (ECM) composition, material properties, and messenger RNA (mRNA) expression were analyzed. mRNA expression of cartilage-specific genes, type II collagen, and aggrecan showed that BMP-2 enhanced chondrocyte stability for up to 3 weeks. After 3 weeks in culture, there was substantially more type I collagen expression and more osteopontin and runt-related transcription factor 2 expression in 5- and 8-week cultures treated with BMP-2 than in controls. Additionally, matrix metalloproteinase-13 and ADAMTS-5 (A disintegrin-like and metalloproteinase with thrombospondin 5) were upregulated in 5- and 8-week cultures treated with BMP-2, coinciding with a loss of ECM density, collagen, and proteoglycan. Eight-week tissue stimulated with BMP-2 was more fragile and tore more easily when removed from the culture dish as compared to controls, suggesting temporal limitations to the effectiveness of BMP-2 in monolayer systems and perhaps other models to enhance the generation of a cartilage-like tissue for tissue engineering purposes.

  7. Materials

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2009-02-01

    Full Text Available . It is generally included as part of a structurally insulated panel (SIP) where the foam is sandwiched between external skins of steel, wood or cement. Cement composites Cement bonded composites are an important class of building materials. These products... for their stone buildings, including the Egyptians, Aztecs and Inca’s. As stone is a very dense material it requires intensive heating to become warm. Rocks were generally stacked dry but mud, and later cement, can be used as a mortar to hold the rocks...

  8. Bone tumors

    International Nuclear Information System (INIS)

    Moylan, D.J.; Yelovich, R.M.

    1991-01-01

    Primary bone malignancies are relatively rare with less than 4,000 new cases per year. Multiple myeloma (more correctly a hematologic malignancy) accounts for 40%; osteosarcomas, 28%; chondrosarcomas, 13%; fibrosarcomas arising in bone, 4%; and Ewing's sarcoma, 7%. The authors discuss various treatments for bone tumors, including radiotherapy, chemotherapy and surgery

  9. 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

  10. 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

    BACKGROUND: Harvesting techniques can affect cellular parameters of autogenous bone grafts in vitro. Whether these differences translate to in vivo bone formation, however, remains unknown. OBJECTIVE: The purpose of this study was to assess the impact of different harvesting techniques on bone fo......: Transplantation of autogenous bone particles harvested with four techniques in the present model resulted in moderate differences in terms of bone formation and graft resorption.......BACKGROUND: Harvesting techniques can affect cellular parameters of autogenous bone grafts in vitro. Whether these differences translate to in vivo bone formation, however, remains unknown. OBJECTIVE: The purpose of this study was to assess the impact of different harvesting techniques on bone...... 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...

  11. 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 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......-SiO (34.47%), followed by BCP 60/40 (23.64%)) was significantly higher than the more rapidly substituted autogenous bone (17.1%). Autogenous bone yielded significantly more new bone (21.81%) over all test groups (4.91%-7.74%) and significantly more osteoid (5.53%) than BCP 60/40 (3%) and DBBM (2...

  12. 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.

  13. Bone banking.

    Science.gov (United States)

    Howard, W

    1999-04-01

    The use of human organs and tissues for transplantation in Australia has increased significantly over the past 30 years. In 1997, the Australian Coordinating Committee on Organ Registries and Donation (ACCORD) reported a total number of 190 organ donors, 636 corneal donors and 1509 bone donors Australia wide. Of the 1509 bone donations, 143 came from cadaveric sources and 1366 were made by living donors. Bone transplantation is not as widely recognised as solid organ or corneal transplantation. Due to improved technology and surgical skills, the demand for bone transplantation has increased markedly. This Clinical Update will provide an overview of the physiological aspects of bone transplantation and explore bone banking, a key step in the complex and critical process of bone transplantation.

  14. The petrous bone

    DEFF Research Database (Denmark)

    Jørkov, Marie Louise Schjellerup; Heinemeier, Jan; Lynnerup, Niels

    2009-01-01

    Intraskeletal variation in the composition of carbon (delta(13)C) and nitrogen (delta(15)N) stable isotopes measured in collagen is tested from various human bones and dentine. Samples were taken from the femur, rib, and petrous part of the temporal bone from well-preserved skeletons of both adults...... (n = 34) and subadults (n = 24). Additional samples of dentine from the root of 1st molars were taken from 16 individuals. The skeletal material is from a medieval cemetery (AD 1200-1573) in Holbaek, Denmark. Our results indicate that the petrous bone has an isotopic signal that differs significantly...... from that of femur and rib within the single skeleton (P bone and the 1st molar. The intraskeletal variation may reflect differences...

  15. Bone microarchitecture and bone mineral density in multiple sclerosis

    DEFF Research Database (Denmark)

    Olsson, A; Oturai, A B; Søndergaard, H B

    2018-01-01

    BACKGROUND: Multiple sclerosis (MS) patients are at increased risk of reduced bone mineral density (BMD) and fractures. The aetiology of bone loss in MS is unclear. Trabecular bone score (TBS) is a novel analytical tool that provides a measurement of the bone microarchitecture. Decreased TBS...... included. TBS was calculated using TBS iNsight software (MediMaps® ). Multivariable regression analyses were performed with information on smoking, alcohol, glucocorticoid (GC) treatment, sun exposure, physical activity, vitamin D and BMI. RESULTS: Trabecular bone score was not significantly different from...... an age-matched reference population. Low TBS was associated with high age (P = .014) and smoking (P = .03). Smoking and physical inactivity were associated with low BMD in spine (P = .034, P = .032). GC treatment was not associated with TBS. CONCLUSION: We could not find altered TBS values among MS...

  16. Receptor tyrosine kinase inhibition causes simultaneous bone loss and excess bone formation within growing bone in rats

    International Nuclear Information System (INIS)

    Nurmio, Mirja; Joki, Henna; Kallio, Jenny; Maeaettae, Jorma A.; Vaeaenaenen, H. Kalervo; Toppari, Jorma; Jahnukainen, Kirsi; Laitala-Leinonen, Tiina

    2011-01-01

    During postnatal skeletal growth, adaptation to mechanical loading leads to cellular activities at the growth plate. It has recently become evident that bone forming and bone resorbing cells are affected by the receptor tyrosine kinase (RTK) inhibitor imatinib mesylate (STI571, Gleevec (registered) ). Imatinib targets PDGF, ABL-related gene, c-Abl, c-Kit and c-Fms receptors, many of which have multiple functions in the bone microenvironment. We therefore studied the effects of imatinib in growing bone. Young rats were exposed to imatinib (150 mg/kg on postnatal days 5-7, or 100 mg/kg on postnatal days 5-13), and the effects of RTK inhibition on bone physiology were studied after 8 and 70 days (3-day treatment), or after 14 days (9-day treatment). X-ray imaging, computer tomography, histomorphometry, RNA analysis and immunohistochemistry were used to evaluate bone modeling and remodeling in vivo. Imatinib treatment eliminated osteoclasts from the metaphyseal osteochondral junction at 8 and 14 days. This led to a resorption arrest at the growth plate, but also increased bone apposition by osteoblasts, thus resulting in local osteopetrosis at the osteochondral junction. The impaired bone remodelation observed on day 8 remained significant until adulthood. Within the same bone, increased osteoclast activity, leading to bone loss, was observed at distal bone trabeculae on days 8 and 14. Peripheral quantitative computer tomography (pQCT) and micro-CT analysis confirmed that, at the osteochondral junction, imatinib shifted the balance from bone resorption towards bone formation, thereby altering bone modeling. At distal trabecular bone, in turn, the balance was turned towards bone resorption, leading to bone loss. - Research highlights: → 3-Day imatinib treatment. → Causes growth plate anomalies in young rats. → Causes biomechanical changes and significant bone loss at distal trabecular bone. → Results in loss of osteoclasts at osteochondral junction.

  17. A novel bio-inorganic bone implant containing deglued bone ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. With the aim of developing an ideal bone graft, a new bone grafting material was developed using ... ing of a HA powder in a chitosan solution and coating of. HA particle .... system and the cell parameters were calculated using the.

  18. Scanning electron microscopy of bone.

    Science.gov (United States)

    Boyde, Alan

    2012-01-01

    This chapter described methods for Scanning Electron Microscopical imaging of bone and bone cells. Backscattered electron (BSE) imaging is by far the most useful in the bone field, followed by secondary electrons (SE) and the energy dispersive X-ray (EDX) analytical modes. This chapter considers preparing and imaging samples of unembedded bone having 3D detail in a 3D surface, topography-free, polished or micromilled, resin-embedded block surfaces, and resin casts of space in bone matrix. The chapter considers methods for fixation, drying, looking at undersides of bone cells, and coating. Maceration with alkaline bacterial pronase, hypochlorite, hydrogen peroxide, and sodium or potassium hydroxide to remove cells and unmineralised matrix is described in detail. Attention is given especially to methods for 3D BSE SEM imaging of bone samples and recommendations for the types of resin embedding of bone for BSE imaging are given. Correlated confocal and SEM imaging of PMMA-embedded bone requires the use of glycerol to coverslip. Cathodoluminescence (CL) mode SEM imaging is an alternative for visualising fluorescent mineralising front labels such as calcein and tetracyclines. Making spatial casts from PMMA or other resin embedded samples is an important use of this material. Correlation with other imaging means, including microradiography and microtomography is important. Shipping wet bone samples between labs is best done in glycerol. Environmental SEM (ESEM, controlled vacuum mode) is valuable in eliminating -"charging" problems which are common with complex, cancellous bone samples.

  19. A comparison of chemical compositions of reported altered oceanic crusts and global MORB data set: implication for isotopic heterogeneity of recycled materials

    Science.gov (United States)

    Shimoda, G.; Kogiso, T.

    2017-12-01

    Chemical composition of altered oceanic crust is one of important constraints to delineate chemical heterogeneity of the mantle. Accordingly, many researchers have been studied to determine bulk chemical composition of altered oceanic crust mainly based on chemical compositions of old oceanic crusts at Site 801 and Site 417/418, and young crust at Site 504 (e.g., Staudigel et al., 1996; Bach et al. 2003; Kuo et al., 2016). Their careful estimation provided reliable bulk chemical compositions of these Sites and revealed common geochemical feature of alteration. To assess effect of recycling of altered oceanic crust on chemical evolution of the mantle, it might be meaningful to discuss whether the reported chemical compositions of altered oceanic crusts can represent chemical composition of globally subducted oceanic crusts. Reported chemical compositions of fresh glass or less altered samples from Site 801, 417/418 and 504 were highly depleted compared to that of global MORB reported by Gale et al. (2013), suggesting that there might be sampling bias. Hence, it could be important to consider chemical difference between oceanic crusts of these three Sites and global MORB to discuss effect of recycling of oceanic crust on isotopic heterogeneity of the mantle. It has been suggested that one of controlling factors of chemical variation of oceanic crust is crustal spreading rate because different degree of partial melting affects chemical composition of magmas produced at a mid-ocean ridge. Crustal spreading rate could also affect intensity of alteration. Namely, oceanic crusts produced at slow-spreading ridges may prone to be altered due to existence of larger displacement faults compared to fast spreading ridges which have relatively smooth topography. Thus, it might be significant to evaluate isotopic evolution of oceanic crusts those were produced at different spreading rates. In this presentation, we will provide a possible chemical variation of altered oceanic

  20. 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.

  1. 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.

  2. Bone development

    DEFF Research Database (Denmark)

    Tatara, M.R.; Tygesen, Malin Plumhoff; Sawa-Wojtanowicz, B.

    2007-01-01

    The objective of this study was to determine the long-term effect of alpha-ketoglutarate (AKG) administration during early neonatal life on skeletal development and function, with emphasis on bone exposed to regular stress and used to serve for systemic changes monitoring, the rib. Shropshire ram.......01). Furthermore, AKG administration induced significantly higher bone mineral density of the cortical bone by 7.1% (P

  3. Functionalization of deproteinized bovine bone with a coating-incorporated depot of BMP-2 renders the material efficiently osteoinductive and suppresses foreign-body reactivity.

    Science.gov (United States)

    Wu, Gang; Hunziker, Ernst B; Zheng, Yuanna; Wismeijer, Daniel; Liu, Yuelian

    2011-12-01

    The repair of critical-sized bony defects remains a challenge in the fields of implantology, maxillofacial surgery and orthopaedics. As an alternative bone-defect filler to autologous bone grafts, deproteinized bovine bone (DBB) is highly osteoconductive and clinically now widely used. However, this product suffers from the disadvantage of not being intrinsically osteoinductive. In the present study, this property was conferred by coating DBB with a layer of calcium phosphate into which bone morphogenetic protein 2 (BMP-2) was incorporated. Granules of DBB bearing a coating-incorporated depot of BMP-2--together with the appropriate controls (DBB bearing a coating but no BMP-2; uncoated DBB bearing adsorbed BMP-2; uncoated DBB bearing no BMP-2)--were implanted subcutaneously in rats. Five weeks later, the implants were withdrawn for a histomorphometric analysis of the volume densities of (i) bone, (ii) bone marrow, (iii) foreign-body giant cells and (iv) fibrous capsular tissue. Parameters (i) and (ii) were highest, whilst parameters (iii) and (iv) were lowest in association with DBB bearing a coating-incorporated depot of BMP-2. Hence, this mode of functionalization not only confers DBB with the property of osteoinductivity but also improves its biocompatibility--thus dually enhancing its clinical potential in the repair of bony defects. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. 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.

  5. Evaluation of the potential of chitosan/beta-1,3-glucan/hydroxyapatite material as a scaffold for living bone graft production in vitro by comparison of ADSC and BMDSC behaviour on its surface

    Czech Academy of Sciences Publication Activity Database

    Przekora, A.; Vandrovcová, Marta; Trávníčková, Martina; Pajorová, Julie; Molitor, M.; Ginalska, G.; Bačáková, Lucie

    2017-01-01

    Roč. 12, č. 1 (2017), č. článku 015030. ISSN 1748-6041 R&D Projects: GA MZd(CZ) NV15-33018A Institutional support: RVO:67985823 Keywords : runx2 * adipose-derived stem cells * bone marrow-derived stem cells * osteogenic differentiation Subject RIV: EI - Biotechnology ; Bionics OBOR OECD: Bioproducts (products that are manufactured using biological material as feedstock) biomaterials, bioplastics, biofuels, bioderived bulk and fine chemicals, bio-derived novel materials Impact factor: 2.469, year: 2016

  6. [Guided bone regeneration: general survey].

    Science.gov (United States)

    Cosyn, Jan; De Bruyn, Hugo

    2009-01-01

    The principle of 'guided bone regeneration' was first described in 1988 on the basis of animal-experimental data. Six weeks after transmandibular defects had been created and protected by non-resorbable teflonmembranes, complete bone regeneration was found. The technique was based on the selective repopulation of the wound: every infiltration of cells outside the neighbouring bone tissue was prevented by the application of the membrane. Additional animal experiments showed that guided bone regeneration was a viable treatment option for local bone defects surrounding dental implants. Clinical practice, however, showed that premature membrane exposure was a common complication, which was responsible for a tremendous reduction in regenerated bone volume. In addition, a second surgical intervention was always necessary to remove the membrane. As a result, resorbable alternatives were developed. Since these are less rigid, bone fillers are usually used simultaneously. These comprise autogenous bone chips and bone substitutes from allogenic or xenogenic origine. Also alloplastic materials could be used for this purpose. Based on their characteristics this article provides an overview of the biomaterials that could be considered for guided bone regeneration. Specific attention goes to their application in clinical practice.

  7. Broken bone

    Science.gov (United States)

    ... Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Broken bone URL of this page: //medlineplus.gov/ency/ ... following steps to reduce your risk of a broken bone: Wear protective ... pads. Create a safe home for young children. Place a gate at stairways ...

  8. Bone densitometry

    DEFF Research Database (Denmark)

    Ravn, Pernille; Alexandersen, P; Møllgaard, A

    1999-01-01

    The bisphosphonates have been introduced as alternatives to hormone replacement therapy (HRT) for the treatment and prevention of postmenopausal osteoporosis. The expected increasing application in at clinical practice demands cost-effective and easily handled methods to monitor the effect on bone....... The weak response at the distal forearm during antiresorptive treatment has restricted the use of bone densitometry at this region. We describe a new model for bone densitometry at the distal forearm, by which the response obtained is comparable to the response in other regions where bone densitometry...... is much more expensive and technically complicated. By computerized iteration of single X-ray absorptiometry forearm scans we defined a region with 65% trabecular bone. The region was analyzed in randomized, double-masked, placebo- controlled trials: a 2-year trial with alendronate (n = 69), a 1-year...

  9. 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.

  10. Bone healing and bone substitutes.

    Science.gov (United States)

    Costantino, Peter D; Hiltzik, David; Govindaraj, Satish; Moche, Jason

    2002-02-01

    With the advent of new biomaterials and surgical techniques, the reconstructive surgeon has a wider range of treatment modalities for the rehabilitation and reconstruction of craniofacial skeletal deformities than ever before. These innovative substances act as true bone graft substitutes, thereby allowing the surgeon to avoid the use of autogenous bone grafts and their associated donor site morbidity. Surgeons have long been interested in producing a composite graft that can heal faster by induction, incorporate with surrounding tissues, and be remodeled to resemble native bone. Currently, there are a host of bone graft substitutes available that vary in both their composition and properties. Craniomaxillofacial surgeons must therefore become comfortable with numerous biomaterials to best tailor the treatment for each patient individually. Ongoing investigations into the next phase of tissue engineering will continue to bring us closer to the ability to regenerate or replace bone.

  11. Bone apatite composition of necrotic trabecular bone in the femoral head of immature piglets.

    Science.gov (United States)

    Aruwajoye, Olumide O; Kim, Harry K W; Aswath, Pranesh B

    2015-04-01

    Ischemic osteonecrosis of the femoral head (IOFH) can lead to excessive resorption of the trabecular bone and collapse of the femoral head as a structure. A well-known mineral component to trabecular bone is hydroxyapatite, which can be present in many forms due to ionic substitution, thus altering chemical composition. Unfortunately, very little is known about the chemical changes to bone apatite following IOFH. We hypothesized that the apatite composition changes in necrotic bone possibly contribute to increased osteoclast resorption and structural collapse of the femoral head. The purpose of this study was to assess the macroscopic and local phosphate composition of actively resorbed necrotic trabecular bone to isolate differences between areas of increased osteoclast resorption and normal bone formation. A piglet model of IOFH was used. Scanning electron microscopy (SEM), histology, X-ray absorbance near edge structure (XANES), and Raman spectroscopy were performed on femoral heads to characterize normal and necrotic trabecular bone. Backscattered SEM, micro-computed tomography and histology showed deformity and active resorption of necrotic bone compared to normal. XANES and Raman spectroscopy obtained from actively resorbed necrotic bone and normal bone showed increased carbonate-to-phosphate content in the necrotic bone. The changes in the apatite composition due to carbonate substitution may play a role in the increased resorption of necrotic bone due to its increase in solubility. Indeed, a better understanding of the apatite composition of necrotic bone could shed light on osteoclast activity and potentially improve therapeutic treatments that target excessive resorption of bone.

  12. Effects of gamma irradiation on microhardness and Fourier Transform Infrared Spectroscopy of bovine bone

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Derly Augusto; Pereira, Daisa L.; Gomes, Gabriela V.; Sugahara, Vanessa M.L.; Mathor, Monica B.; Zezell, Denise Maria, E-mail: zezell@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro para Lasers e Aplicacoes

    2017-07-01

    The skeletal systems with the structural arrangement of the bone are very important for load distribution, mechanical resistance and vital organs protection. The bone structure is multiphase and composed of organic, inorganic (mineral) compounds and water. Gamma radiation is an ionizing radiation that comes from gamma radiation sources or X-ray generator is commonly used in health establishments such as radio diagnostic exams, radiotherapy and sterilization of allograft. The characterization of the irradiated bone tissue can be is an important tool to study of the components that are affected and how much each dose of ionizing radiation can alter its mechanical properties. This information will be very important in in vitro and ex vivo studies where sterilization of the bone material is necessary and may still be useful in understanding the effects on the bone tissue of patients undergoing short-term radiotherapy. For this, 110 samples of bovine femur diaphysis were randomized into 11 groups: G1 untreated (control); G2 to G11 were submitted to gamma irradiation ({sup 60}Co Gammacel). Samples were polished before irradiation and submitted to a Knoop Microhardness Test to determine the hardness of bovine bone and Fourier transform Infrared spectroscopy (FTIR) to biochemical characterization. Spectra were collected in the mid-infrared range in Attenuated Total Reflectance (ATR) sampling mode associated whit PCA multivariate technique to evaluate the molecular changes in bone matrix. It was observed that hardness was not altered by gamma irradiation and FTIR spectroscopy associated with PCA is a good method to analyze the changes in bone tissue submitted to ionizing radiation. (author)

  13. Effects of gamma irradiation on microhardness and Fourier Transform Infrared Spectroscopy of bovine bone

    International Nuclear Information System (INIS)

    Dias, Derly Augusto; Pereira, Daisa L.; Gomes, Gabriela V.; Sugahara, Vanessa M.L.; Mathor, Monica B.; Zezell, Denise Maria

    2017-01-01

    The skeletal systems with the structural arrangement of the bone are very important for load distribution, mechanical resistance and vital organs protection. The bone structure is multiphase and composed of organic, inorganic (mineral) compounds and water. Gamma radiation is an ionizing radiation that comes from gamma radiation sources or X-ray generator is commonly used in health establishments such as radio diagnostic exams, radiotherapy and sterilization of allograft. The characterization of the irradiated bone tissue can be is an important tool to study of the components that are affected and how much each dose of ionizing radiation can alter its mechanical properties. This information will be very important in in vitro and ex vivo studies where sterilization of the bone material is necessary and may still be useful in understanding the effects on the bone tissue of patients undergoing short-term radiotherapy. For this, 110 samples of bovine femur diaphysis were randomized into 11 groups: G1 untreated (control); G2 to G11 were submitted to gamma irradiation ("6"0Co Gammacel). Samples were polished before irradiation and submitted to a Knoop Microhardness Test to determine the hardness of bovine bone and Fourier transform Infrared spectroscopy (FTIR) to biochemical characterization. Spectra were collected in the mid-infrared range in Attenuated Total Reflectance (ATR) sampling mode associated whit PCA multivariate technique to evaluate the molecular changes in bone matrix. It was observed that hardness was not altered by gamma irradiation and FTIR spectroscopy associated with PCA is a good method to analyze the changes in bone tissue submitted to ionizing radiation. (author)

  14. [Preparation of nano-nacre artificial bone].

    Science.gov (United States)

    Chen, Jian-ting; Tang, Yong-zhi; Zhang, Jian-gang; Wang, Jian-jun; Xiao, Ying

    2008-12-01

    To assess the improvements in the properties of nano-nacre artificial bone prepared on the basis of nacre/polylactide acid composite artificial bone and its potential for clinical use. The compound of nano-scale nacre powder and poly-D, L-lactide acid (PDLLA) was used to prepare the cylindrical hollow artificial bone, whose properties including raw material powder scale, pore size, porosity and biomechanical characteristics were compared with another artificial bone made of micron-scale nacre powder and PDLLA. Scanning electron microscope showed that the average particle size of the nano-nacre powder was 50.4-/+12.4 nm, and the average pore size of the artificial bone prepared using nano-nacre powder was 215.7-/+77.5 microm, as compared with the particle size of the micron-scale nacre powder of 5.0-/+3.0 microm and the pore size of the resultant artificial bone of 205.1-/+72.0 microm. The porosities of nano-nacre artificial bone and the micron-nacre artificial bone were (65.4-/+2.9)% and (53.4-/+2.2)%, respectively, and the two artificial bones had comparable compressive strength and Young's modulus, but the flexural strength of the nano-nacre artificial bone was lower than that of the micro-nacre artificial bone. The nano-nacre artificial bone allows better biodegradability and possesses appropriate pore size, porosity and biomechanical properties for use as a promising material in bone tissue engineering.

  15. 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.

  16. Automated radiogrammetry is a feasible method for measuring bone quality and bone maturation in severely disabled children

    International Nuclear Information System (INIS)

    Mergler, Sandra; Man, Stella A. de; Boot, Annemieke M.; Heus, Karen G.C.B.B.; Huijbers, Wim A.R.; Rijn, Rick R. van; Penning, Corine; Evenhuis, Heleen M.

    2016-01-01

    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.)

  17. 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.)

  18. Adhesion, growth and differentiation markers in human osteoblast-like cells cultured on surface-modified metallic materials designed for bone implants

    Czech Academy of Sciences Publication Activity Database

    Bačáková, Lucie; Kabátová, J.; Lisá, Věra; Starý, V.; Fencl, J.

    2006-01-01

    Roč. 9, č. 58-60 (2006), s. 1-3 ISSN 1429-7248 R&D Projects: GA ČR(CZ) GA101/06/0226 Institutional research plan: CEZ:AV0Z50110509 Keywords : bone tissue engineering * metals * surface modifications Subject RIV: EI - Biotechnology ; Bionics

  19. 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.

  20. Microradiographic investigations on experimentally provoked structural alterations in hard tooth tissues after sealing with plastic material in places where caries is apt to develop

    International Nuclear Information System (INIS)

    Falten, E.

    1981-01-01

    The aim of the present investigation was, after sealing three areas in extracted human teeth: fissures, dental necksand approximate areas and subsequent exposure to experimentally produced cariogenous noxae, to establish possible alterations in the area of transition between sealed and unsealed dental enamal. This would provide a further decision-taking aid with regard to the question whether also the remaining parts where caries is apt to develop should be sealed. (orig./MG) [de

  1. Assessment of bone mineral content in the internal bone volume

    International Nuclear Information System (INIS)

    Hoeiseth, A.; Alho, A.; Husby, T.; Ullevaal Sykehus, Oslo

    1991-01-01

    A method for assessing values related to bone density and mass is described. Mean attenuation and pixel area are measured in pixels selected on the basis of CT units. The method is to a large extent computerized and not dependent on manual positioning or outlining of a region of interest. Because it is not dependent on a comparatively large volume of homogeneous bone it can be used to make assessments even in very heterogeneous bones including cortical bone. The method is adaptable for measurement in all parts of the skeleton and values related to both bone density (DRV) and bone mass (MRV) are derived. The measurements in the femoral condyles were shown to have a precision of approximately 0.25 to 0.30 Z-score units (standard deviation of the measurements expressed in Z-score units). The agreement between chemically analyzed calcium density (weight of calcium per volume) and DRV was little less than 0.50 Z-scores and 0.30 Z-scores for the chemically determined calcium mass and the MRV. The agreement with mechanical bone strength was 0.78 Z-scores for DRV and 0.64 for the MRV. Altering scan parameters or measuring approaches gave systematic differences in the measurements. There were, however, good linear correlations between the measurements which show that these different measuring approaches essentially gave identical measurements. (orig.)

  2. Occipital bone lacunae

    International Nuclear Information System (INIS)

    Pavlica, P.; Sciascia, R.

    1988-01-01

    Sixteen patients with lacunar alterations of the squamous occipital bone were studied in various radiographic projections; in many cases studies were also performed. In 7 cases lacunae in the cerebral fossa were observed, with an average diameter of 3 cm. These defects were due to a thinning of the inner table of the theca. In 9 cases smaller lacunae were demonstrated bilaterally, which were more radiolucent, isolated or confluent, located in the area corresponding to the internal occipital protuberance at the ridges of cruciform eminence. The latter were representative of diploic venous lakes, as the best demonstrated in lateral projection. This kind of lacunae are considered as anatomic variants, because no bone destruction is demonstrable, as confirmed by technetium scintigraphy

  3. Bone Biopsy

    Science.gov (United States)

    ... several inches long with a hollow core to capture the bone specimen. The CT scanner is typically ... IV), ultrasound machine and devices that monitor your heart beat and blood pressure. top of page How ...

  4. 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....

  5. Bone sarcomas

    International Nuclear Information System (INIS)

    Mudry, P.

    2008-01-01

    Bone sarcomas are malignancies with peak incidence in adolescents and young adults. The most frequent are osteosarcoma and Ewing sarcoma/PNET, in an older adults are seen chondrosarcomas, other ones are rare. In general, biology of sarcomas is closely related to pediatric malignancies with fast growth, local aggressiveness, tendency to early hematogenic dissemination and chemo sensitivity. Diagnostics and treatment of bone sarcomas should be done in well experienced centres due to low incidence and broad issue of this topic. An interdisciplinary approach and staff education is essential in due care of patients with bone sarcoma. If these criteria are achieved, the cure rate is contemporary at 65 - 70 %, while some subpopulation of patients has chance for cure up to 90 %. Osteosarcoma and Ewing sarcoma/PNET are discussed below as types of most frequent bone sarcoma. (author)

  6. Accelerated bone ingrowth by local delivery of Zinc from bioactive ...

    African Journals Online (AJOL)

    Background: Synthetic bone graft substitutes such as bioactive glass (BG) material are developed in order to achieve successful bone regeneration. Zn plays an important role in the proper bone growth, development, and maintenance of healthy bones. Aims: This study aims to evaluate in vivo the performance therapy of ...

  7. Mandibular reconstruction using bone allografts

    International Nuclear Information System (INIS)

    Chang Joon Yim

    1999-01-01

    Further understanding of bone healing mechanisms, bone physiology and bone biology, transplantation immunology, and development of Tissue Banking procedures has enabled oral and maxillofacial surgeons to reconstruct even the most difficult bony defects successfully with the preserved allogeneic bone implant. Although it had been known that bone allografts were clinically effective, its application has not been widespread until the reports of Inclan (I 942), Hyatt and Butler (I 950), and Wilson (I 95 1). Tissue Banking provides the surgeon with a readily available, relatively inexpensive, and relatively safe selection of allogeneic bone for clinical use. Now autogenous bone and allogeneic bone implants present a wide variety of surgical options to surgeons, whether used separately or in combination. The surgeons are able to make judicious and fruitful choices, only with a thorough knowledge of the above-mentioned biological principles and skillful techniques. Many kinds of bone grafting techniques have been tried for reconstructing defective osseous tissues of the oral and maxillofacial region, though they have varying degrees of success. The osseous defects which require grafting include those of various size, shape, position, or amount. Unlike autogenous grafts, whose function is to provide osteogenic cells, allografts are purely passive, offering only a matrix for the inductive phase of bone healing. The condition of the recipient bed is of primary importance, because the host must produce all of the essential elements for the bone allograft to become incorporated. Depending on the processing methods of the allogeneic bone, the bone graft materials have different qualities, different healing potentials and different indications. Proper selection of grafts and surgical techniques requires an understanding of graft immunology and the mechanisms of graft healing. The surgeons should know about the biological principles to raise the clinical success rate

  8. Biocompatibility of orthopaedic implants on bone forming cells

    OpenAIRE

    Kapanen, A. (Anita)

    2002-01-01

    Abstract Reindeer antler was studied for its possible use as a bone implant material. A molecular biological study showed that antler contains a growth factor promoting bone formation. Ectopic bone formation assay showed that antler is not an equally effective inducer as allogenic material. Ectopic bone formation assay was optimised for biocompatibility studies of orthopaedic NiTi implants. Ti-6Al-4V and stainless steel were used as reference materials. The assay...

  9. Bone health in anorexia