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Bone Powder (bone + powder)
Selected AbstractsTechnical note: Efficiency of total demineralization and ion-exchange column for DNA extraction from boneAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Seung Bum Seo Abstract We investigated whether a combination of recently introduced methods, total demineralization and ion-exchange columns, would increase DNA recovery from old bone. Ten bone samples taken after a burial period of ,60 years were used in this study. Bone powder was digested using total or incomplete demineralization. DNA was extracted by the standard organic method. The DNA extract was purified with ion-exchange columns or QIAquick® spin columns. The efficiency of different DNA extraction methods was compared in terms of DNA concentration, inhibitors generated by real-time PCR, and conventional STR typing results. The mean DNA concentration using the total demineralization method is ,3 times higher than that using the incomplete demineralization method. For DNA purification, the method using QIAquick® spin columns appeared to yield approximately double the DNA than the method using ion-exchange columns. Furthermore, 2 out of 10 samples showed higher levels of inhibition with CT values of IPC ,30 cycles when using only ion-exchange columns. In STR results, total demineralization yielded more locus profiles by 4.2 loci than incomplete demineralization, and QIAquick® spin columns also yielded more locus profiles by 3.5 loci than ion-exchange columns. Total demineralization of bone powder significantly increased DNA yield and improved STR typing results. However, the use of ion-exchange columns was not efficient when compared with the method using QIAquick® spin columns. It is suggested that the combination of total demineralization and QIAquick® spin columns lead to greatly improved STR typing results. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] Histological evaluation of the osteoinduction capability of human dentineINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2006M. E. L. Machado Abstract Aim, To assess whether human dentine has the potential to promote the development of calcified tissues when implanted in the muscle tissue of mice. Methodology, Root canals in extracted human teeth were instrumented to produce dentine fragments. The dentine fragments produced were divided into two. In group 1, fragments were demineralized and sterilized. In group 2, the fragments were not submitted to any additional treatment. The dentine fragments were then implanted in the muscle of mice. In group 3, the muscles were implanted with rehydrated lyophilized human bone powder. Animals were killed following test periods of 7, 15, 30, 60, 120 and 180 days, the fragments were removed together with adjacent muscle and examined under light microscopy to assess calcification. Results, Areas of calcification were observed in groups 1 and 3 after a period of 180 days. In group 2, the surrounding tissues displayed only chronic inflammatory infiltration. Conclusions, On the basis of the experimental model adopted in this study, fibroblast-rich connective tissue formed in groups 1 and 3, which could reflect an osteoinductive process. Further studies are suggested to identify which dentinal factors are capable of inducing the formation of a calcified matrix. [source] Bone regeneration in rabbit sinus lifting associated with bovine BMPJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2004Sergio Allegrini Jr. Abstract Autogenous bone is considered the optimal grafting material for sinus lifting, although its harvesting causes great patient discomfort. Various approaches have been taken in order to obtain sinus lifting with preexisting tissue. However, because of the unsuitability of such tissue, additional materials have been required. Alternatively, biomaterials from humans or other animals are used. In this study, the efficacy of using morphogenetic bovine bone protein (BMPb) to augment the maxillary sinus floor was examined. Four grafting materials were employed: lyophilized bovine bone powder, absorbable collagen flakes, natural hydroxylapatite, and synthetic hydroxylapatite. Two groups of rabbits were studied. In one group, graft material only was used. In the other, graft material was combined with 0.5 mg BMPb. During 8 weeks of observation, polyfluorochrome tracers were injected in subcutaneous tissue to evaluate new bone- deposition periods. Following sacrifice, the samples were examined under fluorescent and light microscopes. Results indicated 33.34% more newly formed bone in BMPb animals than in controls. Graft-material resorption increased, but natural HA showed no significant alterations. The results show that the use of BMPb, although providing osteoinduction, might not promote sufficient bone formation. Nonetheless, this material could provide an alternative to autogenous grafts, thereby avoiding patient discomfort. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 68B: 127,131, 2004 [source] Rapid quantitative bioassay of osteoinductionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2000Huston Davis Adkisson We developed a reproducible, relatively rapid bioassay that quantitatively correlates with the osteoinductive capacity of demineralized bone matrix obtained from human long bones. We have found that Saos human osteosarcoma cells proliferate in response to incubation with demineralized bone matrix and that an index of this proliferative activity correlates with demineralized bone matrix-induced osteogenesis in vivo. The bioassay (Saos cell proliferation) had an interassay coefficient of variation of 23 ± 2% and an intra-assay cocfficient of 11 ± 1%. Cell proliferation was normalized to a standard sample of demineralized bone matrix with a clinically high osteoinductive capacity, which was assigned a value of one. The Saos cell proliferation for each sample was related to the standard and assigned a value placing it into thc low (0.00-0.39), intermediate (0.40-0.69). or high (0.70-1.49) osteoinductivc index group. Osteoinduction of human demineralized bone matrix was quantitated by expressing new bone formation as a function of the total bone volume (new bone plus the demineralized bone powder). The demineralized bone matrix was placed in pouches formed in the rectus abdominis muscles of athymic rats, and endochondral bone formation was assessed at 35 days following implantation, when marrow spaces in the ossicles were formed by new bone bridging the spaces between demineralized bone matrix particles. The proliferative index correlated with the area of new bone formation in histological sections ol the newly formed ossicles. When the proliferative index (the osteoinductive index) was divided into low, intermediate. and high groups, the correlation between it and new bone formation (osteoinduction) was 0.850 (p < 0.0005) in 25 samples of demineralized bone matrix. There was no overlap in the osteoinduction stimulated between the samples with low and high osteoinductive indices. We conclude that the proliferation assay is useful for the routine screening of bone allograft donors for osteoinductivc potential. Furthermore, the two-dimensional area of new bone formation. as it relates to total new bone area, is a quantitative measure of osteoinduction. [source] Technical note: Efficiency of total demineralization and ion-exchange column for DNA extraction from boneAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Seung Bum Seo Abstract We investigated whether a combination of recently introduced methods, total demineralization and ion-exchange columns, would increase DNA recovery from old bone. Ten bone samples taken after a burial period of ,60 years were used in this study. Bone powder was digested using total or incomplete demineralization. DNA was extracted by the standard organic method. The DNA extract was purified with ion-exchange columns or QIAquick® spin columns. The efficiency of different DNA extraction methods was compared in terms of DNA concentration, inhibitors generated by real-time PCR, and conventional STR typing results. The mean DNA concentration using the total demineralization method is ,3 times higher than that using the incomplete demineralization method. For DNA purification, the method using QIAquick® spin columns appeared to yield approximately double the DNA than the method using ion-exchange columns. Furthermore, 2 out of 10 samples showed higher levels of inhibition with CT values of IPC ,30 cycles when using only ion-exchange columns. In STR results, total demineralization yielded more locus profiles by 4.2 loci than incomplete demineralization, and QIAquick® spin columns also yielded more locus profiles by 3.5 loci than ion-exchange columns. Total demineralization of bone powder significantly increased DNA yield and improved STR typing results. However, the use of ion-exchange columns was not efficient when compared with the method using QIAquick® spin columns. It is suggested that the combination of total demineralization and QIAquick® spin columns lead to greatly improved STR typing results. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] Bone Marrow Mesenchymal Stem Cells Form Ectopic Woven Bone In Vivo Through Endochondral Bone FormationARTIFICIAL ORGANS, Issue 4 2009Sophia Chia-Ning Chang Abstract:, Autologous vascularized bone grafts, allografts, and biocompatible artificial bone substitutes each have their shortcomings. Bones regenerated using recombinant human bone morphogenetic proteins, demineralized bone powder, or combinations of these are generally small and do not meet the need. The current trend is to use tissue engineering approaches with bone marrow mesenchymal stem cells (MSCs) to generate bones of a desired size and shape. A suspension of osteogenically induced MSCs (CD11a,, CD29+, CD44+) was added to 2% alginate, gelled by mixing this combination with calcium sulfate (CaSO4 0.2 g/mL), and injected into the subcutaneous pocket in the dorsal aspect of nude mice. Cells of various concentrations (0, 10, 50, and 70 million/mL) were used. These implanted constructs were harvested at predetermined times up to 30 weeks for histology. The doubling time of bovine MSCs is 3.75 ± 1.96 days and the proliferation is rapid. Histological evaluation revealed signs of endochondrosis with woven bone deposition. The equilibrium modulus increased with time in vivo, though less than that of normal tissue. Implants seeded with 70 million cells/mL for 6 months resulted in the best formation of equilibrium modulus. This approach has several advantages: (i) obtaining MSCs is associated with low donor morbidity; (ii) MSCs proliferate rapidly in vitro, and a large number of viable cells can be obtained; and (iii) the MSC/alginate constructs can develop into bone-like nodules with high cell viability. Such a system may be useful in large-scale production of bony implants or in the repair of bony defects. The fact that endochondral bone formation led to woven bone suggests its potential feasibility in regional cell therapy. [source] An in,vitro Assay to Measure Targeted Drug Delivery to Bone MineralCHEMMEDCHEM, Issue 5 2010Wolfgang Jahnke Dr. Abstract Targeted delivery of drugs to their site of action is a promising strategy to decrease adverse effects and enhance efficacy, but successful applications of this strategy have been scarce. Human bone is a tissue with unique properties due to its high hydroxyapatite mineral content. However, with the exception of bisphosphonates, bone mineral has not been targeted in a successful clinical application of drugs that act on bone, such as anti-resorptive or bone anabolic agents. Herein we present an NMR-based in,vitro assay to measure binding affinities of small molecules to hydroxyapatite (HAP) or bone powder. Binding was shown to be specific and competitive, and the assay can be carried out in a direct binding format or in competition mode. A selection of clinically relevant bisphosphonates was ranked by their binding affinity for HAP. The binding affinity decreases in the order: pamidronate > alendronate > zoledronate > risedronate > ibandronate. The differences in binding affinities span a factor of 2.1 between pamidronate and ibandronate, consistent with previous studies. The rank order is very similar with bone powder, although the binding capacity of bone powder is smaller and binding kinetics are slower. A zoledronate derivative that lacks the central hydroxy group binds to HAP with 2.3-fold weaker affinity than zoledronate itself. Any small molecule can be analyzed for its binding to HAP or bone powder, and the binding of common bone-staining agents such as alizarin and its derivatives was confirmed in the new assay. This assay supports a strategy for targeted delivery of drugs to bone by attaching a bone-affinity tag to the active drug substance. [source] | |||||||||||||