WorldWideScience

Sample records for bones maintain distinct

  1. Distinct Characteristics of Mandibular Bone Collagen Relative to Long Bone Collagen: Relevance to Clinical Dentistry

    Directory of Open Access Journals (Sweden)

    Takashi Matsuura

    2014-01-01

    Full Text Available Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

  2. Guided bone augmentation using ceramic space-maintaining devices: the impact of chemistry

    Science.gov (United States)

    Anderud, Jonas; Abrahamsson, Peter; Jimbo, Ryo; Isaksson, Sten; Adolfsson, Erik; Malmström, Johan; Naito, Yoshihito; Wennerberg, Ann

    2015-01-01

    The purpose of the study was to evaluate histologically, whether vertical bone augmentation can be achieved using a hollow ceramic space maintaining device in a rabbit calvaria model. Furthermore, the chemistry of microporous hydroxyapatite and zirconia were tested to determine which of these two ceramics are most suitable for guided bone generation. 24 hollow domes in two different ceramic materials were placed subperiosteal on rabbit skull bone. The rabbits were sacrificed after 12 weeks and the histology results were analyzed regarding bone-to-material contact and volume of newly formed bone. The results suggest that the effect of the microporous structure of hydroxyapatite seems to facilitate for the bone cells to adhere to the material and that zirconia enhance a slightly larger volume of newly formed bone. In conclusion, the results of the current study demonstrated that ceramic space maintaining devices permits new bone formation and osteoconduction within the dome. PMID:25792855

  3. Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory

    Directory of Open Access Journals (Sweden)

    Kara J Blacker

    2016-11-01

    Full Text Available Previous work has demonstrated a distinction between maintenance of two types of spatial information in working memory (WM: spatial locations and spatial relations. While a body of work has investigated the neural mechanisms of sensory-based information like spatial locations, little is known about how spatial relations are maintained in WM. In two experiments, we used fMRI to investigate the involvement of early visual cortex in the maintenance of spatial relations in WM. In both experiments, we found less quadrant-specific BOLD activity in visual cortex when a single spatial relation, compared to a single spatial location, was held in WM. Also across both experiments, we found a consistent set of brain regions that were differentially activated during maintenance of locations versus relations. Maintaining a location, compared to a relation, was associated with greater activity in typical spatial WM regions like posterior parietal cortex and prefrontal regions. Whereas maintaining a relation, compared to a location, was associated with greater activity in the parahippocampal gyrus and precuneus/retrosplenial cortex. Further, in Experiment 2 we manipulated WM load and included trials where participants had to maintain three spatial locations or relations. Under this high load condition, the regions sensitive to locations versus relations were somewhat different than under low load. We also identified regions that were sensitive to load specifically for location or relation maintenance, as well as overlapping regions sensitive to load more generally. These results suggest that the neural substrates underlying WM maintenance of spatial locations and relations are distinct from one another and that the neural representations of these distinct types of spatial information change with load.

  4. Hormone-sensitive lipase-knockout mice maintain high bone density during aging.

    Science.gov (United States)

    Shen, Wen-Jun; Liu, Li-Fen; Patel, Shailja; Kraemer, Fredric B

    2011-08-01

    We tested the hypothesis that the actions of hormone-sensitive lipase (HSL) affect the microenvironment of the bone marrow and that removal of HSL function by gene deletion maintains high bone mass in aging mice. We compared littermate control wild-type (WT) and HSL(-/-) mice during aging for changes in serum biochemical values, trabecular bone density using micro-computed tomography, bone histomorphometry, and characteristics of primary bone marrow cells and preosteoblasts. There is a regulated expression of HSL and genes involved in lipid metabolism in the bone marrow during aging. HSL(-/-) mice have increased serum levels of insulin and osteocalcin with decreased leptin levels. Compared with the marked adipocyte infiltration in WT bone marrow (65% by area) at 14 mo, HSL(-/-) mice have fewer (16%, PHSL(-/-) mice maintain a higher bone density (bone volume/total volume 6.1%) with age than WT mice (2.6%, PHSL(-/-) mice show increased growth rates and higher osteogenic potential, manifested by increased expression of Runx2 (3.5-fold, PHSL directs cells within the bone marrow toward osteoblast differentiation and favors the maintenance of bone density with aging.

  5. Guided bone augmentation using ceramic space-maintaining devices: the impact of chemistry

    Directory of Open Access Journals (Sweden)

    Anderud J

    2015-03-01

    Full Text Available Jonas Anderud,1,2 Peter Abrahamsson,2 Ryo Jimbo,1 Sten Isaksson,2 Erik Adolfsson,3 Johan Malmström,2 Yoshihito Naito,4 Ann Wennerberg1 1Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden; 2Maxillofacial Unit Halmstad, Region Halland, Halmstad, Sweden; 3Swedish Ceramic Institute, IVF, Mölndal, Sweden; 4Department of Oral and Maxillofacial Prosthodontics and Oral Implantology, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan Abstract: The purpose of the study was to evaluate histologically, whether vertical bone augmentation can be achieved using a hollow ceramic space maintaining device in a rabbit calvaria model. Furthermore, the chemistry of microporous hydroxyapatite and zirconia were tested to determine which of these two ceramics are most suitable for guided bone generation. 24 hollow domes in two different ceramic materials were placed subperiosteal on rabbit skull bone. The rabbits were sacrificed after 12 weeks and the histology results were analyzed regarding bone-to-material contact and volume of newly formed bone. The results suggest that the effect of the microporous structure of hydroxyapatite seems to facilitate for the bone cells to adhere to the material and that zirconia enhance a slightly larger volume of newly formed bone. In conclusion, the results of the current study demonstrated that ceramic space maintaining devices permits new bone formation and osteoconduction within the dome. Keywords: hydroxyapatite, zirconia, guided bone regeneration, GBR, histology, membrane

  6. Distinct regulatory mechanisms act to establish and maintain Pax3 expression in the developing neural tube.

    Directory of Open Access Journals (Sweden)

    Steven Moore

    Full Text Available Pattern formation in developing tissues is driven by the interaction of extrinsic signals with intrinsic transcriptional networks that together establish spatially and temporally restricted profiles of gene expression. How this process is orchestrated at the molecular level by genomic cis-regulatory modules is one of the central questions in developmental biology. Here we have addressed this by analysing the regulation of Pax3 expression in the context of the developing spinal cord. Pax3 is induced early during neural development in progenitors of the dorsal spinal cord and is maintained as pattern is subsequently elaborated, resulting in the segregation of the tissue into dorsal and ventral subdivisions. We used a combination of comparative genomics and transgenic assays to define and dissect several functional cis-regulatory modules associated with the Pax3 locus. We provide evidence that the coordinated activity of two modules establishes and refines Pax3 expression during neural tube development. Mutational analyses of the initiating element revealed that in addition to Wnt signaling, Nkx family homeodomain repressors restrict Pax3 transcription to the presumptive dorsal neural tube. Subsequently, a second module mediates direct positive autoregulation and feedback to maintain Pax3 expression. Together, these data indicate a mechanism by which transient external signals are converted into a sustained expression domain by the activities of distinct regulatory elements. This transcriptional logic differs from the cross-repression that is responsible for the spatiotemporal patterns of gene expression in the ventral neural tube, suggesting that a variety of circuits are deployed within the neural tube regulatory network to establish and elaborate pattern formation.

  7. Notch signaling maintains bone marrow mesenchymal progenitors by suppressing osteoblast differentiation.

    Science.gov (United States)

    Hilton, Matthew J; Tu, Xiaolin; Wu, Ximei; Bai, Shuting; Zhao, Haibo; Kobayashi, Tatsuya; Kronenberg, Henry M; Teitelbaum, Steven L; Ross, F Patrick; Kopan, Raphael; Long, Fanxin

    2008-03-01

    Postnatal bone marrow houses mesenchymal progenitor cells that are osteoblast precursors. These cells have established therapeutic potential, but they are difficult to maintain and expand in vitro, presumably because little is known about the mechanisms controlling their fate decisions. To investigate the potential role of Notch signaling in osteoblastogenesis, we used conditional alleles to genetically remove components of the Notch signaling system during skeletal development. We found that disruption of Notch signaling in the limb skeletogenic mesenchyme markedly increased trabecular bone mass in adolescent mice. Notably, mesenchymal progenitors were undetectable in the bone marrow of mice with high bone mass. As a result, these mice developed severe osteopenia as they aged. Moreover, Notch signaling seemed to inhibit osteoblast differentiation through Hes or Hey proteins, which diminished Runx2 transcriptional activity via physical interaction. These results support a model wherein Notch signaling in bone marrow normally acts to maintain a pool of mesenchymal progenitors by suppressing osteoblast differentiation. Thus, mesenchymal progenitors may be expanded in vitro by activating the Notch pathway, whereas bone formation in vivo may be enhanced by transiently suppressing this pathway.

  8. Sclerostin-antibody treatment of glucocorticoid-induced osteoporosis maintained bone mass and strength

    Science.gov (United States)

    Jiang, L.; Lay, E. Y.-A.; Zhong, Z.; Ritchie, R. O.; Li, X.; Ke, H.; Lane, N. E.

    2016-01-01

    Summary This study was to determine if antibody against sclerostin (Scl-Ab) could prevent glucocorticoid (GC)-induced osteoporosis in mice. We found that Scl-Ab prevented GC-induced reduction in bone mass and bone strength and that the anabolic effects of Scl-Ab might be partially achieved through the preservation of osteoblast activity through autophagy. Introduction Glucocorticoids (GCs) inhibit bone formation by altering osteoblast and osteocyte cell activity and lifespan. A monoclonal antibody against sclerostin, Scl-Ab, increased bone mass in both preclinical animal and clinical studies in subjects with low bone mass. The objectives of this study were to determine if treatment with the Scl-Ab could prevent loss of bone mass and strength in a mouse model of GC excess and to elucidate if Scl-Ab modulated bone cell activity through autophagy. Methods We generated reporter mice that globally expressed dsRed fused to LC3, a protein marker for autophagosomes, and evaluated the dose-dependent effects of GCs (0, 0.8, 2.8, and 4 mg/kg/day) and Scl-Ab on autophagic osteoblasts, bone mass, and bone strength. Results GC treatment at 2.8 and 4 mg/kg/day of methylprednisolone significantly lowered trabecular bone volume (Tb-BV/TV) at the lumbar vertebrae and distal femurs, cortical bone mass at the mid-shaft femur (FS), and cortical bone strength compared to placebo (PL). In mice treated with GC and Scl-Ab, Tb-BV/TV increased by 60–125 %, apparent bone strength of the lumbar vertebrae by 30–70 %, FS-BV by 10–18 %, and FS-apparent strength by 13–15 %, as compared to GC vehicle-treated mice. GC treatment at 4 mg/kg/ day reduced the number of autophagic osteoblasts by 70 % on the vertebral trabecular bone surface compared to the placebo group (PL, GC 0 mg), and GC + Scl-Ab treatment. Conclusions Treatment with Scl-Ab prevented GC-induced reduction in both trabecular and cortical bone mass and strength and appeared to maintain osteoblast activity through autophagy. PMID

  9. Marked increase in bone formation markers after cinacalcet treatment by mechanisms distinct from hungry bone syndrome in a haemodialysis patient

    Science.gov (United States)

    Goto, Shunsuke; Fujii, Hideki; Matsui, Yutaka; Fukagawa, Masafumi

    2010-01-01

    A 59-year-old female who was on dialysis due to diabetic nephropathy was referred to our hospital for severe hyperparathyroidism refractory to intravenous vitamin D receptor activator treatment. With subsequent cinacalcet hydrochloride treatment, parathyroid hormone (PTH) levels were only slightly suppressed. However, progressive increases were observed in serum alkaline phosphatase (ALP) and bone-specific alkaline phosphatase (BAP) levels with mild hypocalcaemia. A bone biopsy, obtained immediately before surgical parathyroidectomy after 3 months of cinacalcet treatment, revealed no disappearance of osteoclasts. These data suggest that cinacalcet hydrochloride treatment may induce a marked promotion of bone formation by mechanisms distinct from hungry bone syndrome that usually develops after parathyroidectomy. PMID:25949410

  10. t10c12-CLA maintains higher bone mineral density during aging by modulating osteoclastogenesis and bone marrow adiposity.

    Science.gov (United States)

    Rahman, Md M; Halade, Ganesh V; Williams, Paul J; Fernandes, Gabriel

    2011-09-01

    Conjugated linoleic acid (CLA) has been shown to positively influence calcium and bone metabolism. Earlier, we showed that CLA (equal mixture of c9t11-CLA and t10c12-CLA) could protect age-associated bone loss by modulating inflammatory markers and osteoclastogenesis. Since, c9t11-CLA and t10c12-CLA isomers differentially regulate functional parameters and gene expression in different cell types, we examined the efficacy of individual CLA isomers against age-associated bone loss using 12 months old C57BL/6 female mice fed for 6 months with 10% corn oil (CO), 9.5% CO + 0.5% c9t11-CLA, 9.5% CO + 0.5% t10c12-CLA or 9.5% CO + 0.25% c9t11-CLA + 0.25% t10c12-CLA. Mice fed a t10c12-CLA diet maintained a significantly higher bone mineral density (BMD) in femoral, tibial and lumbar regions than those fed CO and c9t11-CLA diets as measured by dual-energy-X-ray absorptiometry (DXA). The increased BMD was accompanied by a decreased production of osteoclastogenic factors, that is, RANKL, TRAP5b, TNF-alpha and IL-6 in serum. Moreover, a significant reduction of high fat diet-induced bone marrow adiposity was observed in t10c12-CLA fed mice as compared to that of CO and c9t11-CLA fed mice, as measured by Oil-Red-O staining of bone marrow sections. In addition, a significant reduction of osteoclast differentiation and bone resorbing pit formation was observed in t10c12-CLA treated RAW 264.7 cell culture stimulated with RANKL as compared to that of c9t11-CLA and linoleic acid treated cultures. In conclusion, these findings suggest that t10c12-CLA is the most potent CLA isomer and it exerts its anti-osteoporotic effect by modulating osteoclastogenesis and bone marrow adiposity.

  11. Mice deficient in 11beta-hydroxysteroid dehydrogenase type 1 lack bone marrow adipocytes, but maintain normal bone formation

    DEFF Research Database (Denmark)

    Justesen, Jeannette; Mosekilde, Lis; Holmes, Megan

    2004-01-01

    and regenerates active cortisol (corticosterone) from circulating inert 11-keto forms. The aim of the present study was to investigate the role of this intracrine activation of GCs on normal bone physiology in vivo using mice deficient in 11betaHSD1 (HSD1(-/-)). The HSD1(-/-) mice exhibited no significant changes...... in cortical or trabecular bone mass compared with wild-type (Wt) mice. Aged HSD1(-/-) mice showed age-related bone loss similar to that observed in Wt mice. Histomorphometric analysis showed similar bone formation and bone resorption parameters in HSD1(-/-) and Wt mice. However, examination of bone marrow...

  12. Aged human bone marrow stromal cells maintaining bone forming capacity in vivo evaluated using an improved method of visualization

    DEFF Research Database (Denmark)

    Stenderup, Karin; Rosada, Cecilia; Justesen, J;

    2004-01-01

    an in vivo assay for quantifying the bone forming capacity (BFC) and we compared the BFC of osteoblastic cells obtained from young and old donors. Osteoblasts were obtained from human bone marrow stromal cell cultures and implanted subcutaneously in immuno-deficient mice (NOD/LtSz- Prkdc(scid)). After 8...... weeks, the implants were removed and embedded un-decalcified in methyl methacrylate (MMA). Sections were stained histochemically with Goldner's Trichrome stain and immuno-histochemically using human-specific antibodies against known osteogenic markers. Implanted human marrow stromal cells (hMSC) were...... able to form bone in vivo. The donor origin of bone was verified using several human-specific antibodies. Dose-response experiments demonstrated that 5 x 10(5) hMSC per implant gave the maximal bone formation after 8 weeks. No difference in BFC was observed between cells obtained from young (24...

  13. Aromatase inhibitor-associated bone loss in breast cancer patients is distinct from postmenopausal osteoporosis.

    Science.gov (United States)

    Hadji, Peyman

    2009-01-01

    Women with breast cancer are increasingly being diagnosed and treated earlier in the disease process, resulting in significantly improved clinical outcomes. Aromatase inhibitor (AI) therapy has shown superior efficacy compared with tamoxifen in postmenopausal women and is quickly becoming the therapy of choice in this setting. However, adjuvant AI therapy depletes residual estrogen and is associated with rapid bone loss and increased fracture risk distinctly different from those observed in postmenopausal osteoporosis. Aromatase inhibitor-associated bone loss (AIBL) occurs at a rate at least 2-fold higher than bone loss seen in healthy, age-matched postmenopausal women, resulting in a significantly higher fracture incidence regardless of the AI administered. Thus, antiresorptive treatments designed to address postmenopausal osteoporosis may not be sufficient in this unique population. Furthermore, current guidelines for the management of bone health in women with breast cancer may not correctly identify patients who may benefit from therapy. Consequently, breast cancer patients receiving adjuvant AI therapy will require specialized management strategies to identify and treat patients at high risk for fracture. Recently, nitrogen-containing bisphosphonates have emerged as the treatment of choice for the prevention of AIBL and the reduction of fracture risk in this setting.

  14. Two Stage Repair of Composite Craniofacial Defects with Antibiotic Releasing Porous Poly(methyl methacrylate) Space Maintainers and Bone Regeneration

    Science.gov (United States)

    Spicer, Patrick

    Craniofacial defects resulting from trauma and resection present many challenges to reconstruction due to the complex structure, combinations of tissues, and environment, with exposure to the oral, skin and nasal mucosal pathogens. Tissue engineering seeks to regenerate the tissues lost in these defects; however, the composite nature and proximity to colonizing bacteria remain difficult to overcome. Additionally, many tissue engineering approaches have further hurdles to overcome in the regulatory process to clinical translation. As such these studies investigated a two stage strategy employing an antibiotic-releasing porous polymethylmethacrylate space maintainer fabricated with materials currently part of products approved or cleared by the United States Food and Drug Administration, expediting the translation to the clinic. This porous space maintainer holds the bone defect open allowing soft tissue to heal around the defect. The space maintainer can then be removed and one regenerated in the defect. These studies investigated the individual components of this strategy. The porous space maintainer showed similar soft tissue healing and response to non-porous space maintainers in a rabbit composite tissue defect. The antibiotic-releasing space maintainers showed release of antibiotics from 1-5 weeks, which could be controlled by loading and fabrication parameters. In vivo, space maintainers releasing a high dose of antibiotics for an extended period of time increased soft tissue healing over burst release space maintainers in an infected composite tissue defect model in a rabbit mandible. Finally, stabilization of bone defects and regeneration could be improved through scaffold structures and delivery of a bone forming growth factor. These studies illustrate the possibility of the two stage strategy for repair of composite tissue defects of the craniofacial complex.

  15. Evaluation of soft tissue coverage over porous polymethylmethacrylate space maintainers within nonhealing alveolar bone defects.

    Science.gov (United States)

    Kretlow, James D; Shi, Meng; Young, Simon; Spicer, Patrick P; Demian, Nagi; Jansen, John A; Wong, Mark E; Kasper, F Kurtis; Mikos, Antonios G

    2010-12-01

    Current treatment of traumatic craniofacial injuries often involves early free tissue transfer, even if the recipient site is contaminated or lacks soft tissue coverage. There are no current tissue engineering strategies to definitively regenerate tissues in such an environment at an early time point. For a tissue engineering approach to be employed in the treatment of such injuries, a two-stage approach could potentially be used. The present study describes methods for fabrication, characterization, and processing of porous polymethylmethacrylate (PMMA) space maintainers for temporary retention of space in bony craniofacial defects. Carboxymethylcellulose hydrogels were used as a porogen. Implants with controlled porosity and pore interconnectivity were fabricated by varying the ratio of hydrogel:polymer and the amount of carboxymethylcellulose within the hydrogel. The in vivo tissue response to the implants was observed by implanting solid, low-porosity, and high-porosity implants (n = 6) within a nonhealing rabbit mandibular defect that included an oral mucosal defect to allow open communication between the oral cavity and the mandibular defect. Oral mucosal wound healing was observed after 12 weeks and was complete in 3/6 defects filled with solid PMMA implants and 5/6 defects filled with either a low- or high-porosity PMMA implant. The tissue response around and within the pores of the two formulations of porous implants tested in vivo was characterized, with the low-porosity implants surrounded by a minimal but well-formed fibrous capsule in contrast to the high-porosity implants, which were surrounded and invaded by almost exclusively inflammatory tissue. On the basis of these results, PMMA implants with limited porosity hold promise for temporary implantation and space maintenance within clean/contaminated bone defects.

  16. Drosophila Muller F Elements Maintain a Distinct Set of Genomic Properties Over 40 Million Years of Evolution

    Science.gov (United States)

    Leung, Wilson; Shaffer, Christopher D.; Reed, Laura K.; Smith, Sheryl T.; Barshop, William; Dirkes, William; Dothager, Matthew; Lee, Paul; Wong, Jeannette; Xiong, David; Yuan, Han; Bedard, James E. J.; Machone, Joshua F.; Patterson, Seantay D.; Price, Amber L.; Turner, Bryce A.; Robic, Srebrenka; Luippold, Erin K.; McCartha, Shannon R.; Walji, Tezin A.; Walker, Chelsea A.; Saville, Kenneth; Abrams, Marita K.; Armstrong, Andrew R.; Armstrong, William; Bailey, Robert J.; Barberi, Chelsea R.; Beck, Lauren R.; Blaker, Amanda L.; Blunden, Christopher E.; Brand, Jordan P.; Brock, Ethan J.; Brooks, Dana W.; Brown, Marie; Butzler, Sarah C.; Clark, Eric M.; Clark, Nicole B.; Collins, Ashley A.; Cotteleer, Rebecca J.; Cullimore, Peterson R.; Dawson, Seth G.; Docking, Carter T.; Dorsett, Sasha L.; Dougherty, Grace A.; Downey, Kaitlyn A.; Drake, Andrew P.; Earl, Erica K.; Floyd, Trevor G.; Forsyth, Joshua D.; Foust, Jonathan D.; Franchi, Spencer L.; Geary, James F.; Hanson, Cynthia K.; Harding, Taylor S.; Harris, Cameron B.; Heckman, Jonathan M.; Holderness, Heather L.; Howey, Nicole A.; Jacobs, Dontae A.; Jewell, Elizabeth S.; Kaisler, Maria; Karaska, Elizabeth A.; Kehoe, James L.; Koaches, Hannah C.; Koehler, Jessica; Koenig, Dana; Kujawski, Alexander J.; Kus, Jordan E.; Lammers, Jennifer A.; Leads, Rachel R.; Leatherman, Emily C.; Lippert, Rachel N.; Messenger, Gregory S.; Morrow, Adam T.; Newcomb, Victoria; Plasman, Haley J.; Potocny, Stephanie J.; Powers, Michelle K.; Reem, Rachel M.; Rennhack, Jonathan P.; Reynolds, Katherine R.; Reynolds, Lyndsey A.; Rhee, Dong K.; Rivard, Allyson B.; Ronk, Adam J.; Rooney, Meghan B.; Rubin, Lainey S.; Salbert, Luke R.; Saluja, Rasleen K.; Schauder, Taylor; Schneiter, Allison R.; Schulz, Robert W.; Smith, Karl E.; Spencer, Sarah; Swanson, Bryant R.; Tache, Melissa A.; Tewilliager, Ashley A.; Tilot, Amanda K.; VanEck, Eve; Villerot, Matthew M.; Vylonis, Megan B.; Watson, David T.; Wurzler, Juliana A.; Wysocki, Lauren M.; Yalamanchili, Monica; Zaborowicz, Matthew A.; Emerson, Julia A.; Ortiz, Carlos; Deuschle, Frederic J.; DiLorenzo, Lauren A.; Goeller, Katie L.; Macchi, Christopher R.; Muller, Sarah E.; Pasierb, Brittany D.; Sable, Joseph E.; Tucci, Jessica M.; Tynon, Marykathryn; Dunbar, David A.; Beken, Levent H.; Conturso, Alaina C.; Danner, Benjamin L.; DeMichele, Gabriella A.; Gonzales, Justin A.; Hammond, Maureen S.; Kelley, Colleen V.; Kelly, Elisabeth A.; Kulich, Danielle; Mageeney, Catherine M.; McCabe, Nikie L.; Newman, Alyssa M.; Spaeder, Lindsay A.; Tumminello, Richard A.; Revie, Dennis; Benson, Jonathon M.; Cristostomo, Michael C.; DaSilva, Paolo A.; Harker, Katherine S.; Jarrell, Jenifer N.; Jimenez, Luis A.; Katz, Brandon M.; Kennedy, William R.; Kolibas, Kimberly S.; LeBlanc, Mark T.; Nguyen, Trung T.; Nicolas, Daniel S.; Patao, Melissa D.; Patao, Shane M.; Rupley, Bryan J.; Sessions, Bridget J.; Weaver, Jennifer A.; Goodman, Anya L.; Alvendia, Erica L.; Baldassari, Shana M.; Brown, Ashley S.; Chase, Ian O.; Chen, Maida; Chiang, Scott; Cromwell, Avery B.; Custer, Ashley F.; DiTommaso, Tia M.; El-Adaimi, Jad; Goscinski, Nora C.; Grove, Ryan A.; Gutierrez, Nestor; Harnoto, Raechel S.; Hedeen, Heather; Hong, Emily L.; Hopkins, Barbara L.; Huerta, Vilma F.; Khoshabian, Colin; LaForge, Kristin M.; Lee, Cassidy T.; Lewis, Benjamin M.; Lydon, Anniken M.; Maniaci, Brian J.; Mitchell, Ryan D.; Morlock, Elaine V.; Morris, William M.; Naik, Priyanka; Olson, Nicole C.; Osterloh, Jeannette M.; Perez, Marcos A.; Presley, Jonathan D.; Randazzo, Matt J.; Regan, Melanie K.; Rossi, Franca G.; Smith, Melanie A.; Soliterman, Eugenia A.; Sparks, Ciani J.; Tran, Danny L.; Wan, Tiffany; Welker, Anne A.; Wong, Jeremy N.; Sreenivasan, Aparna; Youngblom, Jim; Adams, Andrew; Alldredge, Justin; Bryant, Ashley; Carranza, David; Cifelli, Alyssa; Coulson, Kevin; Debow, Calise; Delacruz, Noelle; Emerson, Charlene; Farrar, Cassandra; Foret, Don; Garibay, Edgar; Gooch, John; Heslop, Michelle; Kaur, Sukhjit; Khan, Ambreen; Kim, Van; Lamb, Travis; Lindbeck, Peter; Lucas, Gabi; Macias, Elizabeth; Martiniuc, Daniela; Mayorga, Lissett; Medina, Joseph; Membreno, Nelson; Messiah, Shady; Neufeld, Lacey; Nguyen, San Francisco; Nichols, Zachary; Odisho, George; Peterson, Daymon; Rodela, Laura; Rodriguez, Priscilla; Rodriguez, Vanessa; Ruiz, Jorge; Sherrill, Will; Silva, Valeria; Sparks, Jeri; Statton, Geeta; Townsend, Ashley; Valdez, Isabel; Waters, Mary; Westphal, Kyle; Winkler, Stacey; Zumkehr, Joannee; DeJong, Randall J.; Hoogewerf, Arlene J.; Ackerman, Cheri M.; Armistead, Isaac O.; Baatenburg, Lara; Borr, Matthew J.; Brouwer, Lindsay K.; Burkhart, Brandon J.; Bushhouse, Kelsey T.; Cesko, Lejla; Choi, Tiffany Y. Y.; Cohen, Heather; Damsteegt, Amanda M.; Darusz, Jess M.; Dauphin, Cory M.; Davis, Yelena P.; Diekema, Emily J.; Drewry, Melissa; Eisen, Michelle E. M.; Faber, Hayley M.; Faber, Katherine J.; Feenstra, Elizabeth; Felzer-Kim, Isabella T.; Hammond, Brandy L.; Hendriksma, Jesse; Herrold, Milton R.; Hilbrands, Julia A.; Howell, Emily J.; Jelgerhuis, Sarah A.; Jelsema, Timothy R.; Johnson, Benjamin K.; Jones, Kelly K.; Kim, Anna; Kooienga, Ross D.; Menyes, Erika E.; Nollet, Eric A.; Plescher, Brittany E.; Rios, Lindsay; Rose, Jenny L.; Schepers, Allison J.; Scott, Geoff; Smith, Joshua R.; Sterling, Allison M.; Tenney, Jenna C.; Uitvlugt, Chris; VanDyken, Rachel E.; VanderVennen, Marielle; Vue, Samantha; Kokan, Nighat P.; Agbley, Kwabea; Boham, Sampson K.; Broomfield, Daniel; Chapman, Kayla; Dobbe, Ali; Dobbe, Ian; Harrington, William; Ibrahem, Marwan; Kennedy, Andre; Koplinsky, Chad A.; Kubricky, Cassandra; Ladzekpo, Danielle; Pattison, Claire; Ramirez, Roman E.; Wande, Lucia; Woehlke, Sarah; Wawersik, Matthew; Kiernan, Elizabeth; Thompson, Jeffrey S.; Banker, Roxanne; Bartling, Justina R.; Bhatiya, Chinmoy I.; Boudoures, Anna L.; Christiansen, Lena; Fosselman, Daniel S.; French, Kristin M.; Gill, Ishwar S.; Havill, Jessen T.; Johnson, Jaelyn L.; Keny, Lauren J.; Kerber, John M.; Klett, Bethany M.; Kufel, Christina N.; May, Francis J.; Mecoli, Jonathan P.; Merry, Callie R.; Meyer, Lauren R.; Miller, Emily G.; Mullen, Gregory J.; Palozola, Katherine C.; Pfeil, Jacob J.; Thomas, Jessica G.; Verbofsky, Evan M.; Spana, Eric P.; Agarwalla, Anant; Chapman, Julia; Chlebina, Ben; Chong, Insun; Falk, I.N.; Fitzgibbons, John D.; Friedman, Harrison; Ighile, Osagie; Kim, Andrew J.; Knouse, Kristin A.; Kung, Faith; Mammo, Danny; Ng, Chun Leung; Nikam, Vinayak S.; Norton, Diana; Pham, Philip; Polk, Jessica W.; Prasad, Shreya; Rankin, Helen; Ratliff, Camille D.; Scala, Victoria; Schwartz, Nicholas U.; Shuen, Jessica A.; Xu, Amy; Xu, Thomas Q.; Zhang, Yi; Rosenwald, Anne G.; Burg, Martin G.; Adams, Stephanie J.; Baker, Morgan; Botsford, Bobbi; Brinkley, Briana; Brown, Carter; Emiah, Shadie; Enoch, Erica; Gier, Chad; Greenwell, Alyson; Hoogenboom, Lindsay; Matthews, Jordan E.; McDonald, Mitchell; Mercer, Amanda; Monsma, Nicholaus; Ostby, Kristine; Ramic, Alen; Shallman, Devon; Simon, Matthew; Spencer, Eric; Tomkins, Trisha; Wendland, Pete; Wylie, Anna; Wolyniak, Michael J.; Robertson, Gregory M.; Smith, Samuel I.; DiAngelo, Justin R.; Sassu, Eric D.; Bhalla, Satish C.; Sharif, Karim A.; Choeying, Tenzin; Macias, Jason S.; Sanusi, Fareed; Torchon, Karvyn; Bednarski, April E.; Alvarez, Consuelo J.; Davis, Kristen C.; Dunham, Carrie A.; Grantham, Alaina J.; Hare, Amber N.; Schottler, Jennifer; Scott, Zackary W.; Kuleck, Gary A.; Yu, Nicole S.; Kaehler, Marian M.; Jipp, Jacob; Overvoorde, Paul J.; Shoop, Elizabeth; Cyrankowski, Olivia; Hoover, Betsy; Kusner, Matt; Lin, Devry; Martinov, Tijana; Misch, Jonathan; Salzman, Garrett; Schiedermayer, Holly; Snavely, Michael; Zarrasola, Stephanie; Parrish, Susan; Baker, Atlee; Beckett, Alissa; Belella, Carissa; Bryant, Julie; Conrad, Turner; Fearnow, Adam; Gomez, Carolina; Herbstsomer, Robert A.; Hirsch, Sarah; Johnson, Christen; Jones, Melissa; Kabaso, Rita; Lemmon, Eric; Vieira, Carolina Marques dos Santos; McFarland, Darryl; McLaughlin, Christopher; Morgan, Abbie; Musokotwane, Sepo; Neutzling, William; Nietmann, Jana; Paluskievicz, Christina; Penn, Jessica; Peoples, Emily; Pozmanter, Caitlin; Reed, Emily; Rigby, Nichole; Schmidt, Lasse; Shelton, Micah; Shuford, Rebecca; Tirasawasdichai, Tiara; Undem, Blair; Urick, Damian; Vondy, Kayla; Yarrington, Bryan; Eckdahl, Todd T.; Poet, Jeffrey L.; Allen, Alica B.; Anderson, John E.; Barnett, Jason M.; Baumgardner, Jordan S.; Brown, Adam D.; Carney, Jordan E.; Chavez, Ramiro A.; Christgen, Shelbi L.; Christie, Jordan S.; Clary, Andrea N.; Conn, Michel A.; Cooper, Kristen M.; Crowley, Matt J.; Crowley, Samuel T.; Doty, Jennifer S.; Dow, Brian A.; Edwards, Curtis R.; Elder, Darcie D.; Fanning, John P.; Janssen, Bridget M.; Lambright, Anthony K.; Lane, Curtiss E.; Limle, Austin B.; Mazur, Tammy; McCracken, Marly R.; McDonough, Alexa M.; Melton, Amy D.; Minnick, Phillip J.; Musick, Adam E.; Newhart, William H.; Noynaert, Joseph W.; Ogden, Bradley J.; Sandusky, Michael W.; Schmuecker, Samantha M.; Shipman, Anna L.; Smith, Anna L.; Thomsen, Kristen M.; Unzicker, Matthew R.; Vernon, William B.; Winn, Wesley W.; Woyski, Dustin S.; Zhu, Xiao; Du, Chunguang; Ament, Caitlin; Aso, Soham; Bisogno, Laura Simone; Caronna, Jason; Fefelova, Nadezhda; Lopez, Lenin; Malkowitz, Lorraine; Marra, Jonathan; Menillo, Daniella; Obiorah, Ifeanyi; Onsarigo, Eric Nyabeta; Primus, Shekerah; Soos, Mahdi; Tare, Archana; Zidan, Ameer; Jones, Christopher J.; Aronhalt, Todd; Bellush, James M.; Burke, Christa; DeFazio, Steve; Does, Benjamin R.; Johnson, Todd D.; Keysock, Nicholas; Knudsen, Nelson H.; Messler, James; Myirski, Kevin; Rekai, Jade Lea; Rempe, Ryan Michael; Salgado, Michael S.; Stagaard, Erica; Starcher, Justin R.; Waggoner, Andrew W.; Yemelyanova, Anastasia K.; Hark, Amy T.; Bertolet, Anne; Kuschner, Cyrus E.; Parry, Kesley; Quach, Michael; Shantzer, Lindsey; Shaw, Mary E.; Smith, Mary A.; Glenn, Omolara; Mason, Portia; Williams, Charlotte; Key, S. Catherine Silver; Henry, Tyneshia C. P.; Johnson, Ashlee G.; White, Jackie X.; Haberman, Adam; Asinof, Sam; Drumm, Kelly; Freeburg, Trip; Safa, Nadia; Schultz, Darrin; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Wellinghoff, Jules; Hoopes, Laura L. M.; Chau, Kim M.; Ward, Alyssa; Regisford, E. Gloria C.; Augustine, LaJerald; Davis-Reyes, Brionna; Echendu, Vivienne; Hales, Jasmine; Ibarra, Sharon; Johnson, Lauriaun; Ovu, Steven; Braverman, John M.; Bahr, Thomas J.; Caesar, Nicole M.; Campana, Christopher; Cassidy, Daniel W.; Cognetti, Peter A.; English, Johnathan D.; Fadus, Matthew C.; Fick, Cameron N.; Freda, Philip J.; Hennessy, Bryan M.; Hockenberger, Kelsey; Jones, Jennifer K.; King, Jessica E.; Knob, Christopher R.; Kraftmann, Karen J.; Li, Linghui; Lupey, Lena N.; Minniti, Carl J.; Minton, Thomas F.; Moran, Joseph V.; Mudumbi, Krishna; Nordman, Elizabeth C.; Puetz, William J.; Robinson, Lauren M.; Rose, Thomas J.; Sweeney, Edward P.; Timko, Ashley S.; Paetkau, Don W.; Eisler, Heather L.; Aldrup, Megan E.; Bodenberg, Jessica M.; Cole, Mara G.; Deranek, Kelly M.; DeShetler, Megan; Dowd, Rose M.; Eckardt, Alexandra K.; Ehret, Sharon C.; Fese, Jessica; Garrett, Amanda D.; Kammrath, Anna; Kappes, Michelle L.; Light, Morgan R.; Meier, Anne C.; O’Rouke, Allison; Perella, Mallory; Ramsey, Kimberley; Ramthun, Jennifer R.; Reilly, Mary T.; Robinett, Deirdre; Rossi, Nadine L.; Schueler, Mary Grace; Shoemaker, Emma; Starkey, Kristin M.; Vetor, Ashley; Vrable, Abby; Chandrasekaran, Vidya; Beck, Christopher; Hatfield, Kristen R.; Herrick, Douglas A.; Khoury, Christopher B.; Lea, Charlotte; Louie, Christopher A.; Lowell, Shannon M.; Reynolds, Thomas J.; Schibler, Jeanine; Scoma, Alexandra H.; Smith-Gee, Maxwell T.; Tuberty, Sarah; Smith, Christopher D.; Lopilato, Jane E.; Hauke, Jeanette; Roecklein-Canfield, Jennifer A.; Corrielus, Maureen; Gilman, Hannah; Intriago, Stephanie; Maffa, Amanda; Rauf, Sabya A.; Thistle, Katrina; Trieu, Melissa; Winters, Jenifer; Yang, Bib; Hauser, Charles R.; Abusheikh, Tariq; Ashrawi, Yara; Benitez, Pedro; Boudreaux, Lauren R.; Bourland, Megan; Chavez, Miranda; Cruz, Samantha; Elliott, GiNell; Farek, Jesse R.; Flohr, Sarah; Flores, Amanda H.; Friedrichs, Chelsey; Fusco, Zach; Goodwin, Zane; Helmreich, Eric; Kiley, John; Knepper, John Mark; Langner, Christine; Martinez, Megan; Mendoza, Carlos; Naik, Monal; Ochoa, Andrea; Ragland, Nicolas; Raimey, England; Rathore, Sunil; Reza, Evangelina; Sadovsky, Griffin; Seydoux, Marie-Isabelle B.; Smith, Jonathan E.; Unruh, Anna K.; Velasquez, Vicente; Wolski, Matthew W.; Gosser, Yuying; Govind, Shubha; Clarke-Medley, Nicole; Guadron, Leslie; Lau, Dawn; Lu, Alvin; Mazzeo, Cheryl; Meghdari, Mariam; Ng, Simon; Pamnani, Brad; Plante, Olivia; Shum, Yuki Kwan Wa; Song, Roy; Johnson, Diana E.; Abdelnabi, Mai; Archambault, Alexi; Chamma, Norma; Gaur, Shailly; Hammett, Deborah; Kandahari, Adrese; Khayrullina, Guzal; Kumar, Sonali; Lawrence, Samantha; Madden, Nigel; Mandelbaum, Max; Milnthorp, Heather; Mohini, Shiv; Patel, Roshni; Peacock, Sarah J.; Perling, Emily; Quintana, Amber; Rahimi, Michael; Ramirez, Kristen; Singhal, Rishi; Weeks, Corinne; Wong, Tiffany; Gillis, Aubree T.; Moore, Zachary D.; Savell, Christopher D.; Watson, Reece; Mel, Stephanie F.; Anilkumar, Arjun A.; Bilinski, Paul; Castillo, Rostislav; Closser, Michael; Cruz, Nathalia M.; Dai, Tiffany; Garbagnati, Giancarlo F.; Horton, Lanor S.; Kim, Dongyeon; Lau, Joyce H.; Liu, James Z.; Mach, Sandy D.; Phan, Thu A.; Ren, Yi; Stapleton, Kenneth E.; Strelitz, Jean M.; Sunjed, Ray; Stamm, Joyce; Anderson, Morgan C.; Bonifield, Bethany Grace; Coomes, Daniel; Dillman, Adam; Durchholz, Elaine J.; Fafara-Thompson, Antoinette E.; Gross, Meleah J.; Gygi, Amber M.; Jackson, Lesley E.; Johnson, Amy; Kocsisova, Zuzana; Manghelli, Joshua L.; McNeil, Kylie; Murillo, Michael; Naylor, Kierstin L.; Neely, Jessica; Ogawa, Emmy E.; Rich, Ashley; Rogers, Anna; Spencer, J. Devin; Stemler, Kristina M.; Throm, Allison A.; Van Camp, Matt; Weihbrecht, Katie; Wiles, T. Aaron; Williams, Mallory A.; Williams, Matthew; Zoll, Kyle; Bailey, Cheryl; Zhou, Leming; Balthaser, Darla M.; Bashiri, Azita; Bower, Mindy E.; Florian, Kayla A.; Ghavam, Nazanin; Greiner-Sosanko, Elizabeth S.; Karim, Helmet; Mullen, Victor W.; Pelchen, Carly E.; Yenerall, Paul M.; Zhang, Jiayu; Rubin, Michael R.; Arias-Mejias, Suzette M.; Bermudez-Capo, Armando G.; Bernal-Vega, Gabriela V.; Colon-Vazquez, Mariela; Flores-Vazquez, Arelys; Gines-Rosario, Mariela; Llavona-Cartagena, Ivan G.; Martinez-Rodriguez, Javier O.; Ortiz-Fuentes, Lionel; Perez-Colomba, Eliezer O.; Perez-Otero, Joseph; Rivera, Elisandra; Rodriguez-Giron, Luke J.; Santiago-Sanabria, Arnaldo J.; Senquiz-Gonzalez, Andrea M.; delValle, Frank R. Soto; Vargas-Franco, Dorianmarie; Velázquez-Soto, Karla I.; Zambrana-Burgos, Joan D.; Martinez-Cruzado, Juan Carlos; Asencio-Zayas, Lillyann; Babilonia-Figueroa, Kevin; Beauchamp-Pérez, Francis D.; Belén-Rodríguez, Juliana; Bracero-Quiñones, Luciann; Burgos-Bula, Andrea P.; Collado-Méndez, Xavier A.; Colón-Cruz, Luis R.; Correa-Muller, Ana I.; Crooke-Rosado, Jonathan L.; Cruz-García, José M.; Defendini-Ávila, Marianna; Delgado-Peraza, Francheska M.; Feliciano-Cancela, Alex J.; Gónzalez-Pérez, Valerie M.; Guiblet, Wilfried; Heredia-Negrón, Aldo; Hernández-Muñiz, Jennifer; Irizarry-González, Lourdes N.; Laboy-Corales, Ángel L.; Llaurador-Caraballo, Gabriela A.; Marín-Maldonado, Frances; Marrero-Llerena, Ulises; Martell-Martínez, Héctor A.; Martínez-Traverso, Idaliz M.; Medina-Ortega, Kiara N.; Méndez-Castellanos, Sonya G.; Menéndez-Serrano, Krizia C.; Morales-Caraballo, Carol I.; Ortiz-DeChoudens, Saryleine; Ortiz-Ortiz, Patricia; Pagán-Torres, Hendrick; Pérez-Afanador, Diana; Quintana-Torres, Enid M.; Ramírez-Aponte, Edwin G.; Riascos-Cuero, Carolina; Rivera-Llovet, Michelle S.; Rivera-Pagán, Ingrid T.; Rivera-Vicéns, Ramón E.; Robles-Juarbe, Fabiola; Rodríguez-Bonilla, Lorraine; Rodríguez-Echevarría, Brian O.; Rodríguez-García, Priscila M.; Rodríguez-Laboy, Abneris E.; Rodríguez-Santiago, Susana; Rojas-Vargas, Michael L.; Rubio-Marrero, Eva N.; Santiago-Colón, Albeliz; Santiago-Ortiz, Jorge L.; Santos-Ramos, Carlos E.; Serrano-González, Joseline; Tamayo-Figueroa, Alina M.; Tascón-Peñaranda, Edna P.; Torres-Castillo, José L.; Valentín-Feliciano, Nelson A.; Valentín-Feliciano, Yashira M.; Vargas-Barreto, Nadyan M.; Vélez-Vázquez, Miguel; Vilanova-Vélez, Luis R.; Zambrana-Echevarría, Cristina; MacKinnon, Christy; Chung, Hui-Min; Kay, Chris; Pinto, Anthony; Kopp, Olga R.; Burkhardt, Joshua; Harward, Chris; Allen, Robert; Bhat, Pavan; Chang, Jimmy Hsiang-Chun; Chen, York; Chesley, Christopher; Cohn, Dara; DuPuis, David; Fasano, Michael; Fazzio, Nicholas; Gavinski, Katherine; Gebreyesus, Heran; Giarla, Thomas; Gostelow, Marcus; Greenstein, Rachel; Gunasinghe, Hashini; Hanson, Casey; Hay, Amanda; He, Tao Jian; Homa, Katie; Howe, Ruth; Howenstein, Jeff; Huang, Henry; Khatri, Aaditya; Kim, Young Lu; Knowles, Olivia; Kong, Sarah; Krock, Rebecca; Kroll, Matt; Kuhn, Julia; Kwong, Matthew; Lee, Brandon; Lee, Ryan; Levine, Kevin; Li, Yedda; Liu, Bo; Liu, Lucy; Liu, Max; Lousararian, Adam; Ma, Jimmy; Mallya, Allyson; Manchee, Charlie; Marcus, Joseph; McDaniel, Stephen; Miller, Michelle L.; Molleston, Jerome M.; Diez, Cristina Montero; Ng, Patrick; Ngai, Natalie; Nguyen, Hien; Nylander, Andrew; Pollack, Jason; Rastogi, Suchita; Reddy, Himabindu; Regenold, Nathaniel; Sarezky, Jon; Schultz, Michael; Shim, Jien; Skorupa, Tara; Smith, Kenneth; Spencer, Sarah J.; Srikanth, Priya; Stancu, Gabriel; Stein, Andrew P.; Strother, Marshall; Sudmeier, Lisa; Sun, Mengyang; Sundaram, Varun; Tazudeen, Noor; Tseng, Alan; Tzeng, Albert; Venkat, Rohit; Venkataram, Sandeep; Waldman, Leah; Wang, Tracy; Yang, Hao; Yu, Jack Y.; Zheng, Yin; Preuss, Mary L.; Garcia, Angelica; Juergens, Matt; Morris, Robert W.; Nagengast, Alexis A.; Azarewicz, Julie; Carr, Thomas J.; Chichearo, Nicole; Colgan, Mike; Donegan, Megan; Gardner, Bob; Kolba, Nik; Krumm, Janice L.; Lytle, Stacey; MacMillian, Laurell; Miller, Mary; Montgomery, Andrew; Moretti, Alysha; Offenbacker, Brittney; Polen, Mike; Toth, John; Woytanowski, John; Kadlec, Lisa; Crawford, Justin; Spratt, Mary L.; Adams, Ashley L.; Barnard, Brianna K.; Cheramie, Martin N.; Eime, Anne M.; Golden, Kathryn L.; Hawkins, Allyson P.; Hill, Jessica E.; Kampmeier, Jessica A.; Kern, Cody D.; Magnuson, Emily E.; Miller, Ashley R.; Morrow, Cody M.; Peairs, Julia C.; Pickett, Gentry L.; Popelka, Sarah A.; Scott, Alexis J.; Teepe, Emily J.; TerMeer, Katie A.; Watchinski, Carmen A.; Watson, Lucas A.; Weber, Rachel E.; Woodard, Kate A.; Barnard, Daron C.; Appiah, Isaac; Giddens, Michelle M.; McNeil, Gerard P.; Adebayo, Adeola; Bagaeva, Kate; Chinwong, Justina; Dol, Chrystel; George, Eunice; Haltaufderhyde, Kirk; Haye, Joanna; Kaur, Manpreet; Semon, Max; Serjanov, Dmitri; Toorie, Anika; Wilson, Christopher; Riddle, Nicole C.; Buhler, Jeremy; Mardis, Elaine R.

    2015-01-01

    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu. PMID:25740935

  17. Drosophila muller f elements maintain a distinct set of genomic properties over 40 million years of evolution.

    Science.gov (United States)

    Leung, Wilson; Shaffer, Christopher D; Reed, Laura K; Smith, Sheryl T; Barshop, William; Dirkes, William; Dothager, Matthew; Lee, Paul; Wong, Jeannette; Xiong, David; Yuan, Han; Bedard, James E J; Machone, Joshua F; Patterson, Seantay D; Price, Amber L; Turner, Bryce A; Robic, Srebrenka; Luippold, Erin K; McCartha, Shannon R; Walji, Tezin A; Walker, Chelsea A; Saville, Kenneth; Abrams, Marita K; Armstrong, Andrew R; Armstrong, William; Bailey, Robert J; Barberi, Chelsea R; Beck, Lauren R; Blaker, Amanda L; Blunden, Christopher E; Brand, Jordan P; Brock, Ethan J; Brooks, Dana W; Brown, Marie; Butzler, Sarah C; Clark, Eric M; Clark, Nicole B; Collins, Ashley A; Cotteleer, Rebecca J; Cullimore, Peterson R; Dawson, Seth G; Docking, Carter T; Dorsett, Sasha L; Dougherty, Grace A; Downey, Kaitlyn A; Drake, Andrew P; Earl, Erica K; Floyd, Trevor G; Forsyth, Joshua D; Foust, Jonathan D; Franchi, Spencer L; Geary, James F; Hanson, Cynthia K; Harding, Taylor S; Harris, Cameron B; Heckman, Jonathan M; Holderness, Heather L; Howey, Nicole A; Jacobs, Dontae A; Jewell, Elizabeth S; Kaisler, Maria; Karaska, Elizabeth A; Kehoe, James L; Koaches, Hannah C; Koehler, Jessica; Koenig, Dana; Kujawski, Alexander J; Kus, Jordan E; Lammers, Jennifer A; Leads, Rachel R; Leatherman, Emily C; Lippert, Rachel N; Messenger, Gregory S; Morrow, Adam T; Newcomb, Victoria; Plasman, Haley J; Potocny, Stephanie J; Powers, Michelle K; Reem, Rachel M; Rennhack, Jonathan P; Reynolds, Katherine R; Reynolds, Lyndsey A; Rhee, Dong K; Rivard, Allyson B; Ronk, Adam J; Rooney, Meghan B; Rubin, Lainey S; Salbert, Luke R; Saluja, Rasleen K; Schauder, Taylor; Schneiter, Allison R; Schulz, Robert W; Smith, Karl E; Spencer, Sarah; Swanson, Bryant R; Tache, Melissa A; Tewilliager, Ashley A; Tilot, Amanda K; VanEck, Eve; Villerot, Matthew M; Vylonis, Megan B; Watson, David T; Wurzler, Juliana A; Wysocki, Lauren M; Yalamanchili, Monica; Zaborowicz, Matthew A; Emerson, Julia A; Ortiz, Carlos; Deuschle, Frederic J; DiLorenzo, Lauren A; Goeller, Katie L; Macchi, Christopher R; Muller, Sarah E; Pasierb, Brittany D; Sable, Joseph E; Tucci, Jessica M; Tynon, Marykathryn; Dunbar, David A; Beken, Levent H; Conturso, Alaina C; Danner, Benjamin L; DeMichele, Gabriella A; Gonzales, Justin A; Hammond, Maureen S; Kelley, Colleen V; Kelly, Elisabeth A; Kulich, Danielle; Mageeney, Catherine M; McCabe, Nikie L; Newman, Alyssa M; Spaeder, Lindsay A; Tumminello, Richard A; Revie, Dennis; Benson, Jonathon M; Cristostomo, Michael C; DaSilva, Paolo A; Harker, Katherine S; Jarrell, Jenifer N; Jimenez, Luis A; Katz, Brandon M; Kennedy, William R; Kolibas, Kimberly S; LeBlanc, Mark T; Nguyen, Trung T; Nicolas, Daniel S; Patao, Melissa D; Patao, Shane M; Rupley, Bryan J; Sessions, Bridget J; Weaver, Jennifer A; Goodman, Anya L; Alvendia, Erica L; Baldassari, Shana M; Brown, Ashley S; Chase, Ian O; Chen, Maida; Chiang, Scott; Cromwell, Avery B; Custer, Ashley F; DiTommaso, Tia M; El-Adaimi, Jad; Goscinski, Nora C; Grove, Ryan A; Gutierrez, Nestor; Harnoto, Raechel S; Hedeen, Heather; Hong, Emily L; Hopkins, Barbara L; Huerta, Vilma F; Khoshabian, Colin; LaForge, Kristin M; Lee, Cassidy T; Lewis, Benjamin M; Lydon, Anniken M; Maniaci, Brian J; Mitchell, Ryan D; Morlock, Elaine V; Morris, William M; Naik, Priyanka; Olson, Nicole C; Osterloh, Jeannette M; Perez, Marcos A; Presley, Jonathan D; Randazzo, Matt J; Regan, Melanie K; Rossi, Franca G; Smith, Melanie A; Soliterman, Eugenia A; Sparks, Ciani J; Tran, Danny L; Wan, Tiffany; Welker, Anne A; Wong, Jeremy N; Sreenivasan, Aparna; Youngblom, Jim; Adams, Andrew; Alldredge, Justin; Bryant, Ashley; Carranza, David; Cifelli, Alyssa; Coulson, Kevin; Debow, Calise; Delacruz, Noelle; Emerson, Charlene; Farrar, Cassandra; Foret, Don; Garibay, Edgar; Gooch, John; Heslop, Michelle; Kaur, Sukhjit; Khan, Ambreen; Kim, Van; Lamb, Travis; Lindbeck, Peter; Lucas, Gabi; Macias, Elizabeth; Martiniuc, Daniela; Mayorga, Lissett; Medina, Joseph; Membreno, Nelson; Messiah, Shady; Neufeld, Lacey; Nguyen, San Francisco; Nichols, Zachary; Odisho, George; Peterson, Daymon; Rodela, Laura; Rodriguez, Priscilla; Rodriguez, Vanessa; Ruiz, Jorge; Sherrill, Will; Silva, Valeria; Sparks, Jeri; Statton, Geeta; Townsend, Ashley; Valdez, Isabel; Waters, Mary; Westphal, Kyle; Winkler, Stacey; Zumkehr, Joannee; DeJong, Randall J; Hoogewerf, Arlene J; Ackerman, Cheri M; Armistead, Isaac O; Baatenburg, Lara; Borr, Matthew J; Brouwer, Lindsay K; Burkhart, Brandon J; Bushhouse, Kelsey T; Cesko, Lejla; Choi, Tiffany Y Y; Cohen, Heather; Damsteegt, Amanda M; Darusz, Jess M; Dauphin, Cory M; Davis, Yelena P; Diekema, Emily J; Drewry, Melissa; Eisen, Michelle E M; Faber, Hayley M; Faber, Katherine J; Feenstra, Elizabeth; Felzer-Kim, Isabella T; Hammond, Brandy L; Hendriksma, Jesse; Herrold, Milton R; Hilbrands, Julia A; Howell, Emily J; Jelgerhuis, Sarah A; Jelsema, Timothy R; Johnson, Benjamin K; Jones, Kelly K; Kim, Anna; Kooienga, Ross D; Menyes, Erika E; Nollet, Eric A; Plescher, Brittany E; Rios, Lindsay; Rose, Jenny L; Schepers, Allison J; Scott, Geoff; Smith, Joshua R; Sterling, Allison M; Tenney, Jenna C; Uitvlugt, Chris; VanDyken, Rachel E; VanderVennen, Marielle; Vue, Samantha; Kokan, Nighat P; Agbley, Kwabea; Boham, Sampson K; Broomfield, Daniel; Chapman, Kayla; Dobbe, Ali; Dobbe, Ian; Harrington, William; Ibrahem, Marwan; Kennedy, Andre; Koplinsky, Chad A; Kubricky, Cassandra; Ladzekpo, Danielle; Pattison, Claire; Ramirez, Roman E; Wande, Lucia; Woehlke, Sarah; Wawersik, Matthew; Kiernan, Elizabeth; Thompson, Jeffrey S; Banker, Roxanne; Bartling, Justina R; Bhatiya, Chinmoy I; Boudoures, Anna L; Christiansen, Lena; Fosselman, Daniel S; French, Kristin M; Gill, Ishwar S; Havill, Jessen T; Johnson, Jaelyn L; Keny, Lauren J; Kerber, John M; Klett, Bethany M; Kufel, Christina N; May, Francis J; Mecoli, Jonathan P; Merry, Callie R; Meyer, Lauren R; Miller, Emily G; Mullen, Gregory J; Palozola, Katherine C; Pfeil, Jacob J; Thomas, Jessica G; Verbofsky, Evan M; Spana, Eric P; Agarwalla, Anant; Chapman, Julia; Chlebina, Ben; Chong, Insun; Falk, I N; Fitzgibbons, John D; Friedman, Harrison; Ighile, Osagie; Kim, Andrew J; Knouse, Kristin A; Kung, Faith; Mammo, Danny; Ng, Chun Leung; Nikam, Vinayak S; Norton, Diana; Pham, Philip; Polk, Jessica W; Prasad, Shreya; Rankin, Helen; Ratliff, Camille D; Scala, Victoria; Schwartz, Nicholas U; Shuen, Jessica A; Xu, Amy; Xu, Thomas Q; Zhang, Yi; Rosenwald, Anne G; Burg, Martin G; Adams, Stephanie J; Baker, Morgan; Botsford, Bobbi; Brinkley, Briana; Brown, Carter; Emiah, Shadie; Enoch, Erica; Gier, Chad; Greenwell, Alyson; Hoogenboom, Lindsay; Matthews, Jordan E; McDonald, Mitchell; Mercer, Amanda; Monsma, Nicholaus; Ostby, Kristine; Ramic, Alen; Shallman, Devon; Simon, Matthew; Spencer, Eric; Tomkins, Trisha; Wendland, Pete; Wylie, Anna; Wolyniak, Michael J; Robertson, Gregory M; Smith, Samuel I; DiAngelo, Justin R; Sassu, Eric D; Bhalla, Satish C; Sharif, Karim A; Choeying, Tenzin; Macias, Jason S; Sanusi, Fareed; Torchon, Karvyn; Bednarski, April E; Alvarez, Consuelo J; Davis, Kristen C; Dunham, Carrie A; Grantham, Alaina J; Hare, Amber N; Schottler, Jennifer; Scott, Zackary W; Kuleck, Gary A; Yu, Nicole S; Kaehler, Marian M; Jipp, Jacob; Overvoorde, Paul J; Shoop, Elizabeth; Cyrankowski, Olivia; Hoover, Betsy; Kusner, Matt; Lin, Devry; Martinov, Tijana; Misch, Jonathan; Salzman, Garrett; Schiedermayer, Holly; Snavely, Michael; Zarrasola, Stephanie; Parrish, Susan; Baker, Atlee; Beckett, Alissa; Belella, Carissa; Bryant, Julie; Conrad, Turner; Fearnow, Adam; Gomez, Carolina; Herbstsomer, Robert A; Hirsch, Sarah; Johnson, Christen; Jones, Melissa; Kabaso, Rita; Lemmon, Eric; Vieira, Carolina Marques Dos Santos; McFarland, Darryl; McLaughlin, Christopher; Morgan, Abbie; Musokotwane, Sepo; Neutzling, William; Nietmann, Jana; Paluskievicz, Christina; Penn, Jessica; Peoples, Emily; Pozmanter, Caitlin; Reed, Emily; Rigby, Nichole; Schmidt, Lasse; Shelton, Micah; Shuford, Rebecca; Tirasawasdichai, Tiara; Undem, Blair; Urick, Damian; Vondy, Kayla; Yarrington, Bryan; Eckdahl, Todd T; Poet, Jeffrey L; Allen, Alica B; Anderson, John E; Barnett, Jason M; Baumgardner, Jordan S; Brown, Adam D; Carney, Jordan E; Chavez, Ramiro A; Christgen, Shelbi L; Christie, Jordan S; Clary, Andrea N; Conn, Michel A; Cooper, Kristen M; Crowley, Matt J; Crowley, Samuel T; Doty, Jennifer S; Dow, Brian A; Edwards, Curtis R; Elder, Darcie D; Fanning, John P; Janssen, Bridget M; Lambright, Anthony K; Lane, Curtiss E; Limle, Austin B; Mazur, Tammy; McCracken, Marly R; McDonough, Alexa M; Melton, Amy D; Minnick, Phillip J; Musick, Adam E; Newhart, William H; Noynaert, Joseph W; Ogden, Bradley J; Sandusky, Michael W; Schmuecker, Samantha M; Shipman, Anna L; Smith, Anna L; Thomsen, Kristen M; Unzicker, Matthew R; Vernon, William B; Winn, Wesley W; Woyski, Dustin S; Zhu, Xiao; Du, Chunguang; Ament, Caitlin; Aso, Soham; Bisogno, Laura Simone; Caronna, Jason; Fefelova, Nadezhda; Lopez, Lenin; Malkowitz, Lorraine; Marra, Jonathan; Menillo, Daniella; Obiorah, Ifeanyi; Onsarigo, Eric Nyabeta; Primus, Shekerah; Soos, Mahdi; Tare, Archana; Zidan, Ameer; Jones, Christopher J; Aronhalt, Todd; Bellush, James M; Burke, Christa; DeFazio, Steve; Does, Benjamin R; Johnson, Todd D; Keysock, Nicholas; Knudsen, Nelson H; Messler, James; Myirski, Kevin; Rekai, Jade Lea; Rempe, Ryan Michael; Salgado, Michael S; Stagaard, Erica; Starcher, Justin R; Waggoner, Andrew W; Yemelyanova, Anastasia K; Hark, Amy T; Bertolet, Anne; Kuschner, Cyrus E; Parry, Kesley; Quach, Michael; Shantzer, Lindsey; Shaw, Mary E; Smith, Mary A; Glenn, Omolara; Mason, Portia; Williams, Charlotte; Key, S Catherine Silver; Henry, Tyneshia C P; Johnson, Ashlee G; White, Jackie X; Haberman, Adam; Asinof, Sam; Drumm, Kelly; Freeburg, Trip; Safa, Nadia; Schultz, Darrin; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Wellinghoff, Jules; Hoopes, Laura L M; Chau, Kim M; Ward, Alyssa; Regisford, E Gloria C; Augustine, LaJerald; Davis-Reyes, Brionna; Echendu, Vivienne; Hales, Jasmine; Ibarra, Sharon; Johnson, Lauriaun; Ovu, Steven; Braverman, John M; Bahr, Thomas J; Caesar, Nicole M; Campana, Christopher; Cassidy, Daniel W; Cognetti, Peter A; English, Johnathan D; Fadus, Matthew C; Fick, Cameron N; Freda, Philip J; Hennessy, Bryan M; Hockenberger, Kelsey; Jones, Jennifer K; King, Jessica E; Knob, Christopher R; Kraftmann, Karen J; Li, Linghui; Lupey, Lena N; Minniti, Carl J; Minton, Thomas F; Moran, Joseph V; Mudumbi, Krishna; Nordman, Elizabeth C; Puetz, William J; Robinson, Lauren M; Rose, Thomas J; Sweeney, Edward P; Timko, Ashley S; Paetkau, Don W; Eisler, Heather L; Aldrup, Megan E; Bodenberg, Jessica M; Cole, Mara G; Deranek, Kelly M; DeShetler, Megan; Dowd, Rose M; Eckardt, Alexandra K; Ehret, Sharon C; Fese, Jessica; Garrett, Amanda D; Kammrath, Anna; Kappes, Michelle L; Light, Morgan R; Meier, Anne C; O'Rouke, Allison; Perella, Mallory; Ramsey, Kimberley; Ramthun, Jennifer R; Reilly, Mary T; Robinett, Deirdre; Rossi, Nadine L; Schueler, Mary Grace; Shoemaker, Emma; Starkey, Kristin M; Vetor, Ashley; Vrable, Abby; Chandrasekaran, Vidya; Beck, Christopher; Hatfield, Kristen R; Herrick, Douglas A; Khoury, Christopher B; Lea, Charlotte; Louie, Christopher A; Lowell, Shannon M; Reynolds, Thomas J; Schibler, Jeanine; Scoma, Alexandra H; Smith-Gee, Maxwell T; Tuberty, Sarah; Smith, Christopher D; Lopilato, Jane E; Hauke, Jeanette; Roecklein-Canfield, Jennifer A; Corrielus, Maureen; Gilman, Hannah; Intriago, Stephanie; Maffa, Amanda; Rauf, Sabya A; Thistle, Katrina; Trieu, Melissa; Winters, Jenifer; Yang, Bib; Hauser, Charles R; Abusheikh, Tariq; Ashrawi, Yara; Benitez, Pedro; Boudreaux, Lauren R; Bourland, Megan; Chavez, Miranda; Cruz, Samantha; Elliott, GiNell; Farek, Jesse R; Flohr, Sarah; Flores, Amanda H; Friedrichs, Chelsey; Fusco, Zach; Goodwin, Zane; Helmreich, Eric; Kiley, John; Knepper, John Mark; Langner, Christine; Martinez, Megan; Mendoza, Carlos; Naik, Monal; Ochoa, Andrea; Ragland, Nicolas; Raimey, England; Rathore, Sunil; Reza, Evangelina; Sadovsky, Griffin; Seydoux, Marie-Isabelle B; Smith, Jonathan E; Unruh, Anna K; Velasquez, Vicente; Wolski, Matthew W; Gosser, Yuying; Govind, Shubha; Clarke-Medley, Nicole; Guadron, Leslie; Lau, Dawn; Lu, Alvin; Mazzeo, Cheryl; Meghdari, Mariam; Ng, Simon; Pamnani, Brad; Plante, Olivia; Shum, Yuki Kwan Wa; Song, Roy; Johnson, Diana E; Abdelnabi, Mai; Archambault, Alexi; Chamma, Norma; Gaur, Shailly; Hammett, Deborah; Kandahari, Adrese; Khayrullina, Guzal; Kumar, Sonali; Lawrence, Samantha; Madden, Nigel; Mandelbaum, Max; Milnthorp, Heather; Mohini, Shiv; Patel, Roshni; Peacock, Sarah J; Perling, Emily; Quintana, Amber; Rahimi, Michael; Ramirez, Kristen; Singhal, Rishi; Weeks, Corinne; Wong, Tiffany; Gillis, Aubree T; Moore, Zachary D; Savell, Christopher D; Watson, Reece; Mel, Stephanie F; Anilkumar, Arjun A; Bilinski, Paul; Castillo, Rostislav; Closser, Michael; Cruz, Nathalia M; Dai, Tiffany; Garbagnati, Giancarlo F; Horton, Lanor S; Kim, Dongyeon; Lau, Joyce H; Liu, James Z; Mach, Sandy D; Phan, Thu A; Ren, Yi; Stapleton, Kenneth E; Strelitz, Jean M; Sunjed, Ray; Stamm, Joyce; Anderson, Morgan C; Bonifield, Bethany Grace; Coomes, Daniel; Dillman, Adam; Durchholz, Elaine J; Fafara-Thompson, Antoinette E; Gross, Meleah J; Gygi, Amber M; Jackson, Lesley E; Johnson, Amy; Kocsisova, Zuzana; Manghelli, Joshua L; McNeil, Kylie; Murillo, Michael; Naylor, Kierstin L; Neely, Jessica; Ogawa, Emmy E; Rich, Ashley; Rogers, Anna; Spencer, J Devin; Stemler, Kristina M; Throm, Allison A; Van Camp, Matt; Weihbrecht, Katie; Wiles, T Aaron; Williams, Mallory A; Williams, Matthew; Zoll, Kyle; Bailey, Cheryl; Zhou, Leming; Balthaser, Darla M; Bashiri, Azita; Bower, Mindy E; Florian, Kayla A; Ghavam, Nazanin; Greiner-Sosanko, Elizabeth S; Karim, Helmet; Mullen, Victor W; Pelchen, Carly E; Yenerall, Paul M; Zhang, Jiayu; Rubin, Michael R; Arias-Mejias, Suzette M; Bermudez-Capo, Armando G; Bernal-Vega, Gabriela V; Colon-Vazquez, Mariela; Flores-Vazquez, Arelys; Gines-Rosario, Mariela; Llavona-Cartagena, Ivan G; Martinez-Rodriguez, Javier O; Ortiz-Fuentes, Lionel; Perez-Colomba, Eliezer O; Perez-Otero, Joseph; Rivera, Elisandra; Rodriguez-Giron, Luke J; Santiago-Sanabria, Arnaldo J; Senquiz-Gonzalez, Andrea M; delValle, Frank R Soto; Vargas-Franco, Dorianmarie; Velázquez-Soto, Karla I; Zambrana-Burgos, Joan D; Martinez-Cruzado, Juan Carlos; Asencio-Zayas, Lillyann; Babilonia-Figueroa, Kevin; Beauchamp-Pérez, Francis D; Belén-Rodríguez, Juliana; Bracero-Quiñones, Luciann; Burgos-Bula, Andrea P; Collado-Méndez, Xavier A; Colón-Cruz, Luis R; Correa-Muller, Ana I; Crooke-Rosado, Jonathan L; Cruz-García, José M; Defendini-Ávila, Marianna; Delgado-Peraza, Francheska M; Feliciano-Cancela, Alex J; Gónzalez-Pérez, Valerie M; Guiblet, Wilfried; Heredia-Negrón, Aldo; Hernández-Muñiz, Jennifer; Irizarry-González, Lourdes N; Laboy-Corales, Ángel L; Llaurador-Caraballo, Gabriela A; Marín-Maldonado, Frances; Marrero-Llerena, Ulises; Martell-Martínez, Héctor A; Martínez-Traverso, Idaliz M; Medina-Ortega, Kiara N; Méndez-Castellanos, Sonya G; Menéndez-Serrano, Krizia C; Morales-Caraballo, Carol I; Ortiz-DeChoudens, Saryleine; Ortiz-Ortiz, Patricia; Pagán-Torres, Hendrick; Pérez-Afanador, Diana; Quintana-Torres, Enid M; Ramírez-Aponte, Edwin G; Riascos-Cuero, Carolina; Rivera-Llovet, Michelle S; Rivera-Pagán, Ingrid T; Rivera-Vicéns, Ramón E; Robles-Juarbe, Fabiola; Rodríguez-Bonilla, Lorraine; Rodríguez-Echevarría, Brian O; Rodríguez-García, Priscila M; Rodríguez-Laboy, Abneris E; Rodríguez-Santiago, Susana; Rojas-Vargas, Michael L; Rubio-Marrero, Eva N; Santiago-Colón, Albeliz; Santiago-Ortiz, Jorge L; Santos-Ramos, Carlos E; Serrano-González, Joseline; Tamayo-Figueroa, Alina M; Tascón-Peñaranda, Edna P; Torres-Castillo, José L; Valentín-Feliciano, Nelson A; Valentín-Feliciano, Yashira M; Vargas-Barreto, Nadyan M; Vélez-Vázquez, Miguel; Vilanova-Vélez, Luis R; Zambrana-Echevarría, Cristina; MacKinnon, Christy; Chung, Hui-Min; Kay, Chris; Pinto, Anthony; Kopp, Olga R; Burkhardt, Joshua; Harward, Chris; Allen, Robert; Bhat, Pavan; Chang, Jimmy Hsiang-Chun; Chen, York; Chesley, Christopher; Cohn, Dara; DuPuis, David; Fasano, Michael; Fazzio, Nicholas; Gavinski, Katherine; Gebreyesus, Heran; Giarla, Thomas; Gostelow, Marcus; Greenstein, Rachel; Gunasinghe, Hashini; Hanson, Casey; Hay, Amanda; He, Tao Jian; Homa, Katie; Howe, Ruth; Howenstein, Jeff; Huang, Henry; Khatri, Aaditya; Kim, Young Lu; Knowles, Olivia; Kong, Sarah; Krock, Rebecca; Kroll, Matt; Kuhn, Julia; Kwong, Matthew; Lee, Brandon; Lee, Ryan; Levine, Kevin; Li, Yedda; Liu, Bo; Liu, Lucy; Liu, Max; Lousararian, Adam; Ma, Jimmy; Mallya, Allyson; Manchee, Charlie; Marcus, Joseph; McDaniel, Stephen; Miller, Michelle L; Molleston, Jerome M; Diez, Cristina Montero; Ng, Patrick; Ngai, Natalie; Nguyen, Hien; Nylander, Andrew; Pollack, Jason; Rastogi, Suchita; Reddy, Himabindu; Regenold, Nathaniel; Sarezky, Jon; Schultz, Michael; Shim, Jien; Skorupa, Tara; Smith, Kenneth; Spencer, Sarah J; Srikanth, Priya; Stancu, Gabriel; Stein, Andrew P; Strother, Marshall; Sudmeier, Lisa; Sun, Mengyang; Sundaram, Varun; Tazudeen, Noor; Tseng, Alan; Tzeng, Albert; Venkat, Rohit; Venkataram, Sandeep; Waldman, Leah; Wang, Tracy; Yang, Hao; Yu, Jack Y; Zheng, Yin; Preuss, Mary L; Garcia, Angelica; Juergens, Matt; Morris, Robert W; Nagengast, Alexis A; Azarewicz, Julie; Carr, Thomas J; Chichearo, Nicole; Colgan, Mike; Donegan, Megan; Gardner, Bob; Kolba, Nik; Krumm, Janice L; Lytle, Stacey; MacMillian, Laurell; Miller, Mary; Montgomery, Andrew; Moretti, Alysha; Offenbacker, Brittney; Polen, Mike; Toth, John; Woytanowski, John; Kadlec, Lisa; Crawford, Justin; Spratt, Mary L; Adams, Ashley L; Barnard, Brianna K; Cheramie, Martin N; Eime, Anne M; Golden, Kathryn L; Hawkins, Allyson P; Hill, Jessica E; Kampmeier, Jessica A; Kern, Cody D; Magnuson, Emily E; Miller, Ashley R; Morrow, Cody M; Peairs, Julia C; Pickett, Gentry L; Popelka, Sarah A; Scott, Alexis J; Teepe, Emily J; TerMeer, Katie A; Watchinski, Carmen A; Watson, Lucas A; Weber, Rachel E; Woodard, Kate A; Barnard, Daron C; Appiah, Isaac; Giddens, Michelle M; McNeil, Gerard P; Adebayo, Adeola; Bagaeva, Kate; Chinwong, Justina; Dol, Chrystel; George, Eunice; Haltaufderhyde, Kirk; Haye, Joanna; Kaur, Manpreet; Semon, Max; Serjanov, Dmitri; Toorie, Anika; Wilson, Christopher; Riddle, Nicole C; Buhler, Jeremy; Mardis, Elaine R; Elgin, Sarah C R

    2015-03-04

    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25-50%) than euchromatic reference regions (3-11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11-27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4-3.6 vs. 8.4-8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu.

  18. Maintaining space in localized ridge augmentation using guided bone regeneration with tenting screw technology.

    Science.gov (United States)

    Chasioti, Evdokia; Chiang, Tat Fai; Drew, Howard J

    2013-01-01

    Prosthetic guided implant surgery requires adequate ridge dimensions for proper implant placement. Various surgical procedures can be used to augment deficient alveolar ridges. Studies have examined new bone formation on deficient ridges, utilizing numerous surgical techniques and biomaterials. The goal is to develop time efficient techniques, which have low morbidity. A crucial factor for successful bone grafting procedures is space maintenance. The article discusses space maintenance tenting screws, used in conjunction with bone allografts and resorbable barrier membranes, to ensure uneventful guided bone regeneration (GBR) enabling optimal implant positioning. The technique utilized has been described in the literature to treat severely resorbed alveolar ridges and additionally can be considered in restoring the vertical and horizontal component of deficient extraction sites. Three cases are presented to illustrate the utilization and effectiveness of tenting screw technology in the treatment of atrophic extraction sockets and for deficient ridges.

  19. Receptor activator of nuclear factor-κB ligand and osteoprotegerin: maintaining the balance to prevent bone loss

    Directory of Open Access Journals (Sweden)

    Anne-Priscille Trouvin

    2010-11-01

    Full Text Available Anne-Priscille Trouvin, Vincent GoëbDepartment of Rheumatology, Rouen University Hospital, Rouen, FranceAbstract: Bone remodeling requires a precise balance between resorption and formation. It is a complex process that involves numerous factors: hormones, growth factors, vitamins, and cytokines, and notably osteoprotegerin (OPG and receptor activator for nuclear factor-κB (RANK ligand. The signaling pathway OPG/RANK/RANKL is key to regulation for maintaining the balance between the activity of osteoblasts and osteoclasts in order to prevent bone loss and ensure a normal bone turnover. In this review, the RANK/RANKL/OPG pathway is described. The multiple interactions of various factors (hormones, cytokines, growth factors, and vitamins with the OPG/RANK/RANKL pathway are also commented on. Finally, the effects of denosumab, a human monoclonal antibody that binds to RANKL and thereby inhibits the activation of osteoclasts, and of strontium ranelate are also described. Indeed, these two new drugs afford appreciable assistance in daily care practice, helping to prevent bone loss in patients with osteoporosis.Keywords: osteoprotegerin, OPG, RANK, RANKL, denosumab, strontium ranelate, osteoporosis

  20. Systematic analysis of reportedly distinct populations of multipotent bone marrow-derived stem cells reveals a lack of distinction.

    Science.gov (United States)

    Lodie, Tracey A; Blickarz, Courtney E; Devarakonda, Tara J; He, Chufa; Dash, Ajeeta B; Clarke, Jennifer; Gleneck, Kristen; Shihabuddin, Lamya; Tubo, Ross

    2002-10-01

    Adult human bone marrow-derived stem cells, having the ability to differentiate into cells of multiple lineages, have been isolated and propagated by varied protocols, including positive (CD105(+))/negative (CD45(-)GlyA(-)) selection with immunomagnetic beads, or direct plating into selective culture media. Each substratum-adherent cell population was subjected to a systematic analysis of their cell surface markers and differentiation potential. In the initial stages of culture, each cell population proliferated slowly, reaching confluence in 10-14 days. Adherent cells proliferated at similar rates whether cultured in serum-free medium supplemented with basic fibroblast growth factor, medium containing 2% fetal bovine serum (FBS) supplemented with epidermal growth factor and platelet-derived growth factor, or medium containing 10% FBS alone. Cell surface marker analysis revealed that more than 95% of the cells were positive for CD105/endoglin, a putative mesenchymal stem cell marker, and negative for CD34, CD31, and CD133, markers of hematopoietic, endothelial, and neural stem cells, respectively, regardless of cell isolation and propagation method. CD44 expression was variable, apparently dependent on serum concentration. Functional similarity of the stem cell populations was also observed, with each different cell population expressing the cell type-specific markers beta-tubulin, type II collagen, and desmin, and demonstrating endothelial tube formation when cultured under conditions favoring neural, cartilage, muscle, and endothelial cell differentiation, respectively. On the basis of these data, adult human bone marrow-derived stem cells cultured in adherent monolayer are virtually indistinguishable, both physically and functionally, regardless of the method of isolation or proliferative expansion.

  1. Lasting antibody responses are mediated by a combination of newly formed and established bone marrow plasma cells drawn from clonally distinct precursors.

    Science.gov (United States)

    Chernova, Irene; Jones, Derek D; Wilmore, Joel R; Bortnick, Alexandra; Yucel, Mesut; Hershberg, Uri; Allman, David

    2014-11-15

    Current models hold that serum Ab titers are maintained chiefly by long-lived bone marrow (BM) plasma cells (PCs). In this study, we characterize the role of subpopulations of BM PCs in long-term humoral responses to T cell-dependent Ag. Surprisingly, our results indicate that 40-50% of BM PCs are recently formed cells, defined, in part, by rapid steady-state turnover kinetics and secretion of low-affinity IgM Abs. Further, for months after immunization with a hapten-protein conjugate, newly formed Ag-induced, IgM-secreting BM PCs were detected in parallel with longer-lived IgG-secreting cells, suggesting ongoing and parallel input to the BM PC pool from two distinct pools of activated B cells. Consistent with this interpretation, IgM and IgG Abs secreted by cells within distinct PC subsets exhibited distinct L chain usage. We conclude that long-term Ab responses are maintained by a dynamic BM PC pool composed of both recently formed and long-lived PCs drawn from clonally disparate precursors.

  2. Lasting antibody responses are mediated by a combination of newly formed and established bone marrow plasma cells drawn from clonally distinct precursors 1

    Science.gov (United States)

    Chernova, Irene; Jones, Derek D.; Wilmore, Joel R.; Bortnick, Alexandra; Yucel, Mesut; Hershberg, Uri; Allman, David

    2014-01-01

    Current models hold that serum antibody titers are maintained chiefly by long-lived bone marrow (BM) plasma cells (PCs). Here we characterize the role of subpopulations of BM PCs in long-term humoral responses to T-cell dependent antigen. Surprisingly, our results indicate that 40–50% of BM PCs are recently formed cells, defined in part by rapid steady state turnover kinetics and secretion of low affinity immunoglobulin-M (IgM) antibodies. Further, for months after immunization with a hapten-protein conjugate newly formed antigen-induced IgM-secreting BM PCs were detected in parallel with longer-lived IgG-secreting cells, suggesting ongoing and parallel input to the BM PC pool from two distinct pools of activated B cells. Consistent with this interpretation, IgM and IgG antibodies secreted by cells within distinct PC subsets exhibited distinct light chain usage. We conclude that long-term antibody responses are maintained by a dynamic BM PC pool comprised of both recently formed and long-lived PCs drawn from clonally disparate precursors. PMID:25326027

  3. Moderate Resistive Training Maintains Bone Mineral Density and Improves Functional Fitness in Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    Danilo Sales Bocalini

    2010-01-01

    Full Text Available Twenty five subjects were randomized to untrained (UN and resistive-trained (RT groups. The RT group exercised three sessions per week at 60%–70% of the load according to individual 1RM test during 24 weeks. Both groups were evaluated before and after protocol period assessing lumbar spine (LS and femoral neck (FN BMD by dual-energy X-ray absorptiometry, VO2 max, and neuromuscular fitness. After 24 weeks, there were significant reductions in LS (0.89±0.16% loss and FN BMD (1.54±0.35% loss for UN but no change was found in the TR (LS: 0.01±0.12% and FN: 0.04±0.05% loss. The UN group had no changes in neuromuscular performance. However, RT exhibited a significant improvement on the functional fitness parameters evaluated, with the exception of agility. Our results indicate RT suppresses the decline in BMD and simultaneously improves the functional fitness of postmenopausal women without hormone replacement therapy, which may reduce fall risk and related bone fractures.

  4. Oncostatin M maintains the hematopoietic microenvironment in the bone marrow by modulating adipogenesis and osteogenesis.

    Directory of Open Access Journals (Sweden)

    Fumi Sato

    Full Text Available The bone marrow (BM is an essential organ for hematopoiesis in adult, in which proliferation and differentiation of hematopoietic stem/progenitor cells (HSPC is orchestrated by various stromal cells. Alterations of BM hematopoietic environment lead to various hematopoietic disorders as exemplified by the linking of fatty marrow with increased adipogenesis to anemia or pancytopenia. Therefore, the composition of mesenchymal stromal cell (MSC-derived cells in the BM could be crucial for proper hematopoiesis, but the mechanisms underlying the MSC differentiation for hematopoiesis remain poorly understood. In this study, we show that Oncostatin M (OSM knock out mice exhibited pancytopenia advancing fatty marrow with age. OSM strongly inhibited adipogenesis from BM MSC in vitro, whereas it enhanced their osteogenesis but suppressed the terminal differentiation. Intriguingly, OSM allowed the MSC-derived cells to support the ex vivo expansion of HSPC effectively as feeder cells. Furthermore, the administration of OSM in lethally irradiated wild-type mice blocked fatty marrow and enhanced the recovery of HSPC number in the BM and peripheral blood cells after engraftment of HSPC. Collectively, OSM plays multiple critical roles in the maintenance and development of the hematopoietic microenvironment in the BM at a steady state as well as after injury.

  5. Metaphyseal and diaphyseal bone loss in the tibia following transient muscle paralysis are spatiotemporally distinct resorption events.

    Science.gov (United States)

    Ausk, Brandon J; Huber, Philippe; Srinivasan, Sundar; Bain, Steven D; Kwon, Ronald Y; McNamara, Erin A; Poliachik, Sandra L; Sybrowsky, Christian L; Gross, Ted S

    2013-12-01

    When the skeleton is catabolically challenged, there is great variability in the timing and extent of bone resorption observed at cancellous and cortical bone sites. It remains unclear whether this resorptive heterogeneity, which is often evident within a single bone, arises from increased permissiveness of specific sites to bone resorption or localized resorptive events of varied robustness. To explore this question, we used the mouse model of calf paralysis induced bone loss, which results in metaphyseal and diaphyseal bone resorption of different timing and magnitude. Given this phenotypic pattern of resorption, we hypothesized that bone loss in the proximal tibia metaphysis and diaphysis occurs through resorption events that are spatially and temporally distinct. To test this hypothesis, we undertook three complimentary in vivo/μCT imaging studies. Specifically, we defined spatiotemporal variations in endocortical bone resorption during the 3weeks following calf paralysis, applied a novel image registration approach to determine the location where bone resorption initiates within the proximal tibia metaphysis, and explored the role of varied basal osteoclast activity on the magnitude of bone loss initiation in the metaphysis using μCT based bone resorption parameters. A differential response of metaphyseal and diaphyseal bone resorption was observed throughout each study. Acute endocortical bone loss following muscle paralysis occurred almost exclusively within the metaphyseal compartment (96.5% of total endocortical bone loss within 6days). Using our trabecular image registration approach, we further resolved the initiation of metaphyseal bone loss to a focused region of significant basal osteoclast function (0.03mm(3)) adjacent to the growth plate. This correlative observation of paralysis induced bone loss mediated by basal growth plate cell dynamics was supported by the acute metaphyseal osteoclastic response of 5-week vs. 13-month-old mice. Specifically

  6. The role of vitamin D in maintaining bone health in older people.

    Science.gov (United States)

    Hill, Thomas R; Aspray, Terry J

    2017-04-01

    This review summarises aspects of vitamin D metabolism, the consequences of vitamin D deficiency, and the impact of vitamin D supplementation on musculoskeletal health in older age. With age, changes in vitamin D exposure, cutaneous vitamin D synthesis and behavioural factors (including physical activity, diet and sun exposure) are compounded by changes in calcium and vitamin D pathophysiology with altered calcium absorption, decreased 25-OH vitamin D [25(OH)D] hydroxylation, lower renal fractional calcium reabsorption and a rise in parathyroid hormone. Hypovitaminosis D is common and associated with a risk of osteomalacia, particularly in older adults, where rates of vitamin D deficiency range from 10-66%, depending on the threshold of circulating 25(OH)D used, population studied and season. The relationship between vitamin D status and osteoporosis is less clear. While circulating 25(OH)D has a linear relationship with bone mineral density (BMD) in some epidemiological studies, this is not consistent across all racial groups. The results of randomized controlled trials of vitamin D supplementation on BMD are also inconsistent, and some studies may be less relevant to the older population, as, for example, half of participants in the most robust meta-analysis were aged under 60 years. The impact on BMD of treating vitamin D deficiency (and osteomalacia) is also rarely considered in such intervention studies. When considering osteoporosis, fracture risk is our main concern, but vitamin D therapy has no consistent fracture-prevention effect, except in studies where calcium is coprescribed (particularly in frail populations living in care homes). As a J-shaped effect on falls and fracture risk is becoming evident with vitamin D interventions, we should target those at greatest risk who may benefit from vitamin D supplementation to decrease falls and fractures, although the optimum dose is still unclear.

  7. A Distinct Slow-Cycling Cancer Stem-like Subpopulation of Pancreatic Adenocarcinoma Cells is maintained in Vivo

    Energy Technology Data Exchange (ETDEWEB)

    Dembinski, Jennifer L., E-mail: jennifer.dembinski@rr-research.no; Krauss, Stefan [Cellular and Genetic Therapy, Department of Microbiology, Cancer Stem Cell Innovation Center (CAST), Oslo University Hospital, Rikshospitalet, Oslo (Norway)

    2010-11-29

    Pancreatic adenocarcinoma has the worst prognosis of any major malignancy, with <5% of patients surviving five years. This can be contributed to the often late diagnosis, lack of sufficient treatment and metastatic spread. Heterogeneity within tumors is increasingly becoming a focus in cancer research, as novel therapies are required to target the most aggressive subpopulations of cells that are frequently termed cancer stem cells (CSCs). In the current study, we describe the identification of a slow-cycling cancer stem-like population of cells in vivo in BxPC-3 and Panc03.27 xenografts. A distinct slow-cycling label-retaining population of cells (DiI+/SCC) was found both at the edge of tumors, and in small circumscribed areas within the tumors. DiI+/SCC in these areas display an epithelial-to-mesenchymal transition (EMT) fingerprint, including an upregulation of the mesenchymal markers vimentin and N-cadherin and a loss of the epithelial marker E-cadherin. DiI+/SCC also displayed a critical re-localization of beta-catenin from the membrane to the nucleus. Additionally, the DiI+/SCC population was found to express the developmental signaling molecule sonic hedgehog. This study represents a novel step in defining the biological activities of a tumorigenic subpopulation within the heterogeneous tumor microenvironment in vivo. Understanding the interactions and functions of a CSC population within the context of the tumor microenvironment is critical to design targeted therapeutics.

  8. Multiparameter Analysis of Human Bone Marrow Stromal Cells Identifies Distinct Immunomodulatory and Differentiation-Competent Subtypes

    NARCIS (Netherlands)

    S. James (Sally); J. Fox (James); F. Afsari (Farinaz); J. Lee (Jennifer); S. Clough (Sally); C. Knight (Charlotte); J. Ashmore (James); P. Ashton (Peter); O. Preham (Olivier); M.J. Hoogduijn (Martin); R.D.A.R. Ponzoni (Raquel De Almeida Rocha); Y. Hancock; M. Coles (Mark); P.G. Genever (Paul)

    2015-01-01

    textabstractBone marrow stromal cells (BMSCs, also called bone-marrow-derived mesenchymal stromal cells) provide hematopoietic support and immunoregulation and contain a stem cell fraction capable of skeletogenic differentiation. We used immortalized human BMSC clonal lines for multi-level analysis

  9. Role of bone marrow macrophages in controlling homeostasis and repair in bone and bone marrow niches.

    Science.gov (United States)

    Kaur, Simranpreet; Raggatt, Liza Jane; Batoon, Lena; Hume, David Arthur; Levesque, Jean-Pierre; Pettit, Allison Robyn

    2017-01-01

    Macrophages, named for their phagocytic ability, participate in homeostasis, tissue regeneration and inflammatory responses. Bone and adjacent marrow contain multiple functionally unique resident tissue macrophage subsets which maintain and regulate anatomically distinct niche environments within these interconnected tissues. Three subsets of bone-bone marrow resident tissue macrophages have been characterised; erythroblastic island macrophages, haematopoietic stem cell niche macrophages and osteal macrophages. The role of these macrophages in controlling homeostasis and repair in bone and bone marrow niches is reviewed in detail.

  10. Clinical and radiographic delineation of Bent Bone Dysplasia-FGFR2 type or Bent Bone Dysplasia with Distinctive Clavicles and Angel-shaped Phalanges.

    Science.gov (United States)

    Krakow, Deborah; Cohn, Daniel H; Wilcox, William R; Noh, Grace J; Raffel, Leslie J; Sarukhanov, Anna; Ivanova, Margarita H; Danielpour, Moise; Grange, Dorothy K; Elliott, Alison M; Bernstein, Jonathan A; Rimoin, David L; Merrill, Amy E; Lachman, Ralph S

    2016-10-01

    Bent Bone Dysplasia-FGFR2 type is a relatively recently described bent bone phenotype with diagnostic clinical, radiographic, and molecular characteristics. Here we report on 11 individuals, including the original four patients plus seven new individuals with three longer-term survivors. The prenatal phenotype included stillbirth, bending of the femora, and a high incidence of polyhydramnios, prematurity, and perinatal death in three of 11 patients in the series. The survivors presented with characteristic radiographic findings that were observed among those with lethality, including bent bones, distinctive (moustache-shaped) small clavicles, angel-shaped metacarpals and phalanges, poor mineralization of the calvarium, and craniosynostosis. Craniofacial abnormalities, hirsutism, hepatic abnormalities, and genitourinary abnormalities were noted as well. Longer-term survivors all needed ventilator support. Heterozygosity for mutations in the gene that encodes Fibroblast Growth Factor Receptor 2 (FGFR2) was identified in the nine individuals with available DNA. Description of these patients expands the prenatal and postnatal findings of Bent Bone Dysplasia-FGFR2 type and adds to the phenotypic spectrum among all FGFR2 disorders. © 2016 Wiley Periodicals, Inc.

  11. Sphingosine-1-phosphate mediates proliferation maintaining the multipotency of human adult bone marrow and adipose tissue-derived stem cells.

    Science.gov (United States)

    He, Xiaoli; H'ng, Shiau-Chen; Leong, David T; Hutmacher, Dietmar W; Melendez, Alirio J

    2010-08-01

    High renewal and maintenance of multipotency of human adult stem cells (hSCs), are a prerequisite for experimental analysis as well as for potential clinical usages. The most widely used strategy for hSC culture and proliferation is using serum. However, serum is poorly defined and has a considerable degree of inter-batch variation, which makes it difficult for large-scale mesenchymal stem cells (MSCs) expansion in homogeneous culture conditions. Moreover, it is often observed that cells grown in serum-containing media spontaneously differentiate into unknown and/or undesired phenotypes. Another way of maintaining hSC development is using cytokines and/or tissue-specific growth factors; this is a very expensive approach and can lead to early unwanted differentiation. In order to circumvent these issues, we investigated the role of sphingosine-1-phosphate (S1P), in the growth and multipotency maintenance of human bone marrow and adipose tissue-derived MSCs. We show that S1P induces growth, and in combination with reduced serum, or with the growth factors FGF and platelet-derived growth factor-AB, S1P has an enhancing effect on growth. We also show that the MSCs cultured in S1P-supplemented media are able to maintain their differentiation potential for at least as long as that for cells grown in the usual serum-containing media. This is shown by the ability of cells grown in S1P-containing media to be able to undergo osteogenic as well as adipogenic differentiation. This is of interest, since S1P is a relatively inexpensive natural product, which can be obtained in homogeneous high-purity batches: this will minimize costs and potentially reduce the unwanted side effects observed with serum. Taken together, S1P is able to induce proliferation while maintaining the multipotency of different human stem cells, suggesting a potential for S1P in developing serum-free or serum-reduced defined medium for adult stem cell cultures.

  12. Bone marrow mesenchymal stem cells from patients with aplastic anemia maintain functional and immune properties and do not contribute to the pathogenesis of the disease.

    Science.gov (United States)

    Bueno, Clara; Roldan, Mar; Anguita, Eduardo; Romero-Moya, Damia; Martín-Antonio, Beatriz; Rosu-Myles, Michael; del Cañizo, Consuelo; Campos, Francisco; García, Regina; Gómez-Casares, Maite; Fuster, Jose Luis; Jurado, Manuel; Delgado, Mario; Menendez, Pablo

    2014-07-01

    Aplastic anemia is a life-threatening bone marrow failure disorder characterized by peripheral pancytopenia and marrow hypoplasia. The majority of cases of aplastic anemia remain idiopathic, although hematopoietic stem cell deficiency and impaired immune responses are hallmarks underlying the bone marrow failure in this condition. Mesenchymal stem/stromal cells constitute an essential component of the bone marrow hematopoietic microenvironment because of their immunomodulatory properties and their ability to support hematopoiesis, and they have been involved in the pathogenesis of several hematologic malignancies. We investigated whether bone marrow mesenchymal stem cells contribute, directly or indirectly, to the pathogenesis of aplastic anemia. We found that mesenchymal stem cell cultures can be established from the bone marrow of aplastic anemia patients and display the same phenotype and differentiation potential as their counterparts from normal bone marrow. Mesenchymal stem cells from aplastic anemia patients support the in vitro homeostasis and the in vivo repopulating function of CD34(+) cells, and maintain their immunosuppressive and anti-inflammatory properties. These data demonstrate that bone marrow mesenchymal stem cells from patients with aplastic anemia do not have impaired functional and immunological properties, suggesting that they do not contribute to the pathogenesis of the disease.

  13. Bone marrow-derived mesenchymal stem cells maintain the resting phenotype of microglia and inhibit microglial activation.

    Directory of Open Access Journals (Sweden)

    Ke Yan

    Full Text Available Many studies have shown that microglia in the activated state may be neurotoxic. It has been proven that uncontrolled or over-activated microglia play an important role in many neurodegenerative disorders. Bone marrow-derived mesenchymal stem cells (BMSCs have been shown in many animal models to have a therapeutic effect on neural damage. Such a therapeutic effect is attributed to the fact that BMSCs have the ability to differentiate into neurons and to produce trophic factors, but there is little information available in the literature concerning whether BMSCs play a therapeutic role by affecting microglial activity. In this study, we triggered an inflammatory response situation in vitro by stimulating microglia with the bacterial endotoxin lipopolysaccharide (LPS, and then culturing these microglia with BMSC-conditioned medium (BMSC-CM. We found that BMSC-CM significantly inhibited proliferation and secretion of pro-inflammatory factors by activated microglia. Furthermore, we found that the phagocytic capacity of microglia was also inhibited by BMSC-CM. Finally, we investigated whether the induction of apoptosis and the production of nitric oxide (NO were involved in the inhibition of microglial activation. We found that BMSC-CM significantly induced apoptosis of microglia, while no apoptosis was apparent in the LPS-stimulated microglia. Our study also provides evidence that NO participates in the inhibitory effect of BMSCs. Our experimental results provide evidence that BMSCs have the ability to maintain the resting phenotype of microglia or to control microglial activation through their production of several factors, indicating that BMSCs could be a promising therapeutic tool for treatment of diseases associated with microglial activation.

  14. Scanning Electron Microscopy Reveals Two Distinct Classes of Erythroblastic Island Isolated from Adult Mammalian Bone Marrow.

    Science.gov (United States)

    Yeo, Jia Hao; McAllan, Bronwyn M; Fraser, Stuart T

    2016-04-01

    Erythroblastic islands are multicellular clusters in which a central macrophage supports the development and maturation of red blood cell (erythroid) progenitors. These clusters play crucial roles in the pathogenesis observed in animal models of hematological disorders. The precise structure and function of erythroblastic islands is poorly understood. Here, we have combined scanning electron microscopy and immuno-gold labeling of surface proteins to develop a better understanding of the ultrastructure of these multicellular clusters. The erythroid-specific surface antigen Ter-119 and the transferrin receptor CD71 exhibited distinct patterns of protein sorting during erythroid cell maturation as detected by immuno-gold labeling. During electron microscopy analysis we observed two distinct classes of erythroblastic islands. The islands varied in size and morphology, and the number and type of erythroid cells interacting with the central macrophage. Assessment of femoral marrow isolated from a cavid rodent species (guinea pig, Cavis porcellus) and a marsupial carnivore species (fat-tailed dunnarts, Sminthopsis crassicaudata) showed that while the morphology of the central macrophage varied, two different types of erythroblastic islands were consistently identifiable. Our findings suggest that these two classes of erythroblastic islands are conserved in mammalian evolution and may play distinct roles in red blood cell production.

  15. Estrogens maintain bone mass by regulating expression of genes controlling function and life span in mature osteoclasts.

    Science.gov (United States)

    Imai, Yuuki; Youn, Ming-Young; Kondoh, Shino; Nakamura, Takashi; Kouzmenko, Alexander; Matsumoto, Takahiro; Takada, Ichiro; Takaoka, Kunio; Kato, Shigeaki

    2009-09-01

    Estrogens play a key role in regulation of bone mass and strength by controlling activity of bone-forming osteoblasts and bone-resorbing osteoclasts. Cellular effects of estrogens are mediated predominantly by the action of estrogen receptor alpha (ERalpha). In earlier studies, ablation of the ERalpha gene in mice did not result in osteoporotic phenotypes due to systemic endocrine disturbance and compensatory effects of elevated levels of testosterone. Despite the relatively well-established effects in osteoblasts, little is known about the direct action of estrogen in osteoclasts. Development in the last decade of more sophisticated genetic manipulation approaches opened new possibilities to explore cell-specific roles of nuclear receptors in bone tissue. Recently, we have generated osteoclast-specific ERalpha gene knockout mice and shown that in vivo estrogens directly regulate the life span of mature osteoclasts by inducing the expression of pro-apoptotic Fas ligand (FasL). Inhibitory effects of estrogens on osteoclast function were further studied in vitro. We observed sufficiently detectable ERalpha expression in osteoclasts differentiating from primary bone marrow cells or RAW264 cells, although levels of ERalpha were decreasing during progression of the differentiation into mature osteoclasts. Treatment with estrogens led to reduction in expression of osteoclast-specific genes controlling bone resorption activity. However, estrogens did not affect the size of multinucleated osteoclasts or number of nuclei in a mature osteoclast. In conclusion, in osteoclasts, estrogens function to inhibit bone resorption activity and vitality rather than differentiation.

  16. Differential expression of surface markers in mouse bone marrow mesenchymal stromal cell subpopulations with distinct lineage commitment.

    Directory of Open Access Journals (Sweden)

    Maria Rostovskaya

    Full Text Available Bone marrow mesenchymal stromal cells (BM MSCs represent a heterogeneous population of progenitors with potential for generation of skeletal tissues. However the identity of BM MSC subpopulations is poorly defined mainly due to the absence of specific markers allowing in situ localization of those cells and isolation of pure cell types. Here, we aimed at characterization of surface markers in mouse BM MSCs and in their subsets with distinct differentiation potential. Using conditionally immortalized BM MSCs we performed a screening with 176 antibodies and high-throughput flow cytometry, and found 33 markers expressed in MSCs, and among them 3 were novel for MSCs and 13 have not been reported for MSCs from mice. Furthermore, we obtained clonally derived MSC subpopulations and identified bipotential progenitors capable for osteo- and adipogenic differentiation, as well as monopotential osteogenic and adipogenic clones, and thus confirmed heterogeneity of MSCs. We found that expression of CD200 was characteristic for the clones with osteogenic potential, whereas SSEA4 marked adipogenic progenitors lacking osteogenic capacity, and CD140a was expressed in adipogenic cells independently of their efficiency for osteogenesis. We confirmed our observations in cell sorting experiments and further investigated the expression of those markers during the course of differentiation. Thus, our findings provide to our knowledge the most comprehensive characterization of surface antigens expression in mouse BM MSCs to date, and suggest CD200, SSEA4 and CD140a as markers differentially expressed in distinct types of MSC progenitors.

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

    DEFF Research Database (Denmark)

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

    2002-01-01

    Human bone marrow stromal cells (hMSCs) were stably transduced by a retroviral vector containing the gene for the catalytic subunit of human telomerase (hTERT). Transduced cells (hMSC-TERTs) had telomerase activity, and the mean telomere length was increased as compared with that of control cells......, did not form tumors, and had a normal karyotype. When implanted subcutaneously in immunodeficient mice, the transduced cells formed more bone than did normal cells. These results suggest that ectopic expression of telomerase in hMSCs prevents senescence-associated impairment of osteoblast functions....

  18. Neutron activation analysis in the central nervous system tissues and bones of rats maintained on minerally unbalanced diets

    Energy Technology Data Exchange (ETDEWEB)

    Yasui, Masayuki; Ota, Kiichiro [Wakayama Medical Coll. (Japan); Sasajima, Kazuhisa

    1994-07-01

    It is presumed that by the shortage of Mg, Zn and Ca, functional or organic diseases may occur. When Al deposits to central nervous tissues and bones, various diseases are induced. As the degeneracy of central nervous system, in which minerals are presumed to take part, amyotrophic lateral sclerosis, Parkinsonism dementia, Alzheimer disease and Parkinson`s disease are enumerated. Four groups of Winstar rats were bred for 90 days with standard diet, low Ca diet, low Ca and Mg diet and low Ca and Mg, high Al diet, and the contents of Mg, Ca and Zn in the tissues of various parts were analyzed by plasma luminescence analysis, and the content of Al was analyzed by activation analysis. The results for blood serum, bones, soft tissues and the correlation of respective minerals in thighbones and lumbars are reported. It was presumed that the adjustment of the mineralization of bones was disturbed by low Ca and Mg diet, and consequently, also the adjustment of Al, Mn, Zn and other elements caused failure in living bodies. It is considered that as the adjustment of the mineralization of bones was disturbed, the deposit of Al in living bodies was increased. The possibility of preventing Al deposit can be expected by the rational adjustment of mineral metabolism. (K.I.).

  19. Rat bone marrow-derived dendritic cells generated with GM-CSF/IL-4 or FLT3L exhibit distinct phenotypical and functional characteristics.

    Science.gov (United States)

    N'diaye, Marie; Warnecke, Andreas; Flytzani, Sevasti; Abdelmagid, Nada; Ruhrmann, Sabrina; Olsson, Tomas; Jagodic, Maja; Harris, Robert A; Guerreiro-Cacais, Andre Ortlieb

    2016-03-01

    Dendritic cells are professional APCs that play a central role in the initiation of immune responses. The limited ex vivo availability of dendritic cells inspires the widespread use of bone marrow-derived dendritic cells as an alternative in research. However, the functional characteristics of bone marrow-derived dendritic cells are incompletely understood. Therefore, we compared functional and phenotypic characteristics of rat bone marrow-derived dendritic cells generated with GM-CSF/IL-4 or FLT3 ligand bone marrow-derived dendritic cells. A comparison of surface markers revealed that FLT3 ligand-bone marrow-derived dendritic cells expressed signal regulatory protein α, CD103, and CD4 and baseline levels of MHC class II, CD40, and CD86, which were highly up-regulated upon stimulation. Conversely, GM-CSF/IL-4-bone marrow-derived dendritic cells constitutively expressed signal regulatory protein α, CD11c, and CD11b but only mildly up-regulated MHC class II, CD40, or CD86 following stimulation. Expression of dendritic cell-associated core transcripts was restricted to FLT3 ligand-bone marrow-derived dendritic cells . GM-CSF/IL-4-bone marrow-derived dendritic cells were superior at phagocytosis but were outperformed by FLT3 ligand-bone marrow-derived dendritic cells at antigen presentation and T cell stimulation in vitro. Stimulated GM-CSF/IL-4-bone marrow-derived dendritic cells secreted more TNF, CCL5, CCL20, and NO, whereas FLT3 ligand-bone marrow-derived dendritic cells secreted more IL-6 and IL-12. Finally, whereas GM-CSF/IL-4-bone marrow-derived dendritic cell culture supernatants added to resting T cell cultures promoted forkhead box p3(+) regulatory T cell populations, FLT3 ligand-bone marrow-derived dendritic cell culture supernatants drove Th17 differentiation. We conclude that rat GM-CSF/IL-4-bone marrow-derived dendritic cells and FLT3 ligand-bone marrow-derived dendritic cells are functionally distinct. Our data support the current rationale that FLT3

  20. Investigating the impact of socioeconomic status on the effectiveness of a pamphlet on achieving and maintaining bone health in breast cancer survivors: a patient education resource development primer.

    Science.gov (United States)

    Adirim, Tara; Chafranskaia, Aleksandra; Nyhof-Young, Joyce

    2012-03-01

    Considerable need exists to raise awareness of breast cancer (BC) treatment-induced bone loss and provide management and preventative strategies. We describe the development and evaluation process of an educational pamphlet for BC survivors on achieving and maintaining bone health. A Participatory Design approach was used. The pamphlet was first critically evaluated by interdisciplinary healthcare professionals and less vulnerable members of the target audience prior to evaluation by 45 BC survivors, who completed two questionnaires inquiring about demographics and pamphlet evaluation and satisfaction. Pamphlet effectiveness was correlated with income and education to determine differences between socioeconomic groups. Perceived knowledge increased significantly after reading the brochure for all groups. Socioeconomic status had no impact on pamphlet effectiveness. This methodological approach is presented as a blueprint to promote knowledge translation in cancer patient education contexts aiming to provide cancer patients with the best possible resources for effective self-management of their conditions.

  1. Paget disease of bone-associated UBA domain mutations of SQSTM1 exert distinct effects on protein structure and function

    Science.gov (United States)

    Goode, Alice; Long, Jed E.; Shaw, Barry; Ralston, Stuart H.; Visconti, Micaela Rios; Gianfrancesco, Fernando; Esposito, Teresa; Gennari, Luigi; Merlotti, Daniela; Rendina, Domenico; Rea, Sarah L.; Sultana, Melanie; Searle, Mark S.; Layfield, Robert

    2014-01-01

    SQSTM1 mutations are common in patients with Paget disease of bone (PDB), with most affecting the C-terminal ubiquitin-associated (UBA) domain of the SQSTM1 protein. We performed structural and functional analyses of two UBA domain mutations, an I424S mutation relatively common in UK PDB patients, and an A427D mutation associated with a severe phenotype in Southern Italian patients. Both impaired SQSTM1's ubiquitin-binding function in pull-down assays and resulted in activation of basal NF-κB signalling, compared to wild-type, in reporter assays. We found evidence for a relationship between the ability of different UBA domain mutants to activate NF-κB signalling in vitro and number of affected sites in vivo in 1152 PDB patients from the UK and Italy, with A427D-SQSTM1 producing the greatest level of activation (relative to wild-type) of all PDB mutants tested to date. NMR and isothermal titration calorimetry studies were able to demonstrate that I424S is associated with global structural changes in the UBA domain, resulting in 10-fold weaker UBA dimer stability than wild-type and reduced ubiquitin-binding affinity of the UBA monomer. Our observations provide insights into the role of SQSTM1-mediated NF-κB signalling in PDB aetiology, and demonstrate that different mutations in close proximity within loop 2/helix 3 of the SQSTM1 UBA domain exert distinct effects on protein structure and stability, including indirect effects at the UBA/ubiquitin-binding interface. PMID:24642144

  2. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

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

  3. 钛膜引导骨生长保持牙槽骨骨量的临床研究%Clinical research on using titanium membrane to promote bone regeneration and maintain content of alveolar bone

    Institute of Scientific and Technical Information of China (English)

    吴纪楠; 胡文; 梁国谦

    2008-01-01

    Objective To evaluated the clinical skills and results of using Titanium Membrane to promot bone regeneration and maintain bone volume after tooth extraction. Methods 62 patients with one frant teeth removed were randomly divided into 3 groups. Group Ⅰ(21 patients) was used as control. The socket was not treated. In group Ⅱ(20 patients), the socket was covered by Titanium Membrance. In group Ⅲ(21 patients), the socket was filled with artificial bone and covered with titanium Membrane. The heitht and density of the surrounding alveolar bone were measured 1, 2, 3 and 6 months after extraction. Results The results revealed that the bone height and the alveolar bone density were diffirent in these 3 groups. The absorption rate of the 3 groups were (26.42 ± 0.89)%, (14.71 ± 0.92)% and (7.43 ± 0.76)% separately. The bone density in the 3 group were 0.192 ± 0.056, 0.123 ± 0.043 and 0.389 ± 0.058 separately. Conclusion Titanium Membrane might help to maintain the bone volume after tooth extraction.%目的 评价钛膜在拔牙后引导骨生长保持牙槽骨骨量的临床效果,并探讨其应用技巧.方法 选取 62例只拔除1颗前牙的病例,随机分为3组,第1组(21例)为对照组,拔牙后3 ~ 4个月回院接受种植牙手术,第2组(20例)为钛膜组,拔牙后牙槽窝经过修整,放置稍大于牙槽窝的纯钛膜并将周围组织拉拢缝合,5 ~ 6个月回院接受种植牙手术或钛膜取出手术.第3组(21例)为钛膜加人工骨组,拔牙后牙槽窝即刻填入人工骨并放置稍大于牙槽窝的纯钛膜并缝合,5 ~ 6个月回院接受种植牙手术或钛膜取出手术.在曲面断层片上测量牙槽骨高度的变化.以上各组分别于拔牙后1、2、3及6个月后进行牙槽骨密度的测量.结果 在拔牙后5 ~ 6个月时,牙槽骨平均退缩率分别为(26.42 ± 0.89)%,(14.71 ± 0.92)%,(7.43 ± 0.76)%.第1、2组间差异具有统计学意义(P < 0.01);在术后1 ~ 2个月时,第2、3组

  4. The Preventive Effect of Calcium Supplementation on Weak Bones Caused by the Interaction of Exercise and Food Restriction in Young Female Rats During the Period from Acquiring Bone Mass to Maintaining Bone Mass

    OpenAIRE

    Aikawa, Yuki; Agata, Umon; Kakutani, Yuya; Kato, Shoyo; Noma, Yuichi; Hattori, Satoshi; Ogata, Hitomi; Ezawa, Ikuko; Omi, Naomi

    2016-01-01

    Increasing calcium (Ca) intake is important for female athletes with a risk of weak bone caused by inadequate food intake. The aim of the present study was to examine the preventive effect of Ca supplementation on low bone strength in young female athletes with inadequate food intake, using the rats as an experimental model. Seven-week-old female Sprague-Dawley rats were divided into four groups: the sedentary and ad libitum feeding group (SED), voluntary running exercise and ad libitum feedi...

  5. Acid ceramidase maintains the chondrogenic phenotype of expanded primary chondrocytes and improves the chondrogenic differentiation of bone marrow-derived mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Calogera M Simonaro

    Full Text Available Acid ceramidase is required to maintain the metabolic balance of several important bioactive lipids, including ceramide, sphingosine and sphingosine-1-phosphate. Here we show that addition of recombinant acid ceramidase (rAC to primary chondrocyte culture media maintained low levels of ceramide and led to elevated sphingosine by 48 hours. Surprisingly, after three weeks of expansion the chondrogenic phenotype of these cells also was markedly improved, as assessed by a combination of histochemical staining (Alcian Blue and Safranin-O, western blotting (e.g., Sox9, aggrecan, collagen 2A1, and/or qPCR. The same effects were evident in rat, equine and human cells, and were observed in monolayer and 3-D cultures. rAC also reduced the number of apoptotic cells in some culture conditions, contributing to overall improved cell quality. In addition to these effects on primary chondrocytes, when rAC was added to freshly harvested rat, equine or feline bone marrow cultures an ~2-fold enrichment of mesenchymal stem cells (MSCs was observed by one week. rAC also improved the chondrogenic differentiation of MSCs, as revealed by histochemical and immunostaining. These latter effects were synergistic with TGF-beta1. Based on these results we propose that rAC could be used to improve the outcome of cell-based cartilage repair by maintaining the quality of the expanded cells, and also might be useful in vivo to induce endogenous cartilage repair in combination with other techniques. The results also suggest that short-term changes in sphingolipid metabolism may lead to longer-term effects on the chondrogenic phenotype.

  6. Osteoblastomatosis of bone. A benign, multifocal osteoblastic lesion, distinct from osteoid osteoma and osteoblastoma, radiologically simulating a vascular tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kyriakos, Michael [Washington University School of Medicine, Division of Surgical Pathology, Campus Box 8118, St. Louis, MO (United States); El-Khoury, Georges Y. [University of Iowa, Department of Radiology, Roy J. and Lucille A. Carver School of Medicine, Iowa City, IA (United States); McDonald, Douglas J. [Washington University School of Medicine, Department of Orthopaedic Surgery, St. Louis, MO (United States); Buckwalter, Joseph A. [University of Iowa, Department of Orthopaedics, Roy J. and Lucille A. Carver School of Medicine, Iowa City, IA (United States); Sundaram, Murali [Cleveland Clinic Foundation, Department of Radiology, Cleveland, OH (United States); DeYoung, Barry [University of Iowa, Department of Pathology, School of Medicine, Iowa City, IA (United States); O' Brien, Michael P. [University of Wisconsin Hospital, Department of Radiology, Madison, WI (United States)

    2007-03-15

    Two adult patients are described with multifocal osteolytic lesions radiologically simulating a vascular tumor. One patient had multiple bones involved. Histologically, the individual lesions had the features of the nidus of osteoid osteoma/osteoblastoma. A review of the English language medical literature yielded only one other reported case with similar features. The process is designated as osteoblastomatosis to indicate its bone-forming character, prominent osteoblast proliferation, and multiplicity. The cases are distinguished from multifocal/multicentric osteoid osteoma and osteoblastoma, and from benign and malignant vascular tumors. (orig.)

  7. Distinct Ca2+ channels maintain a high motility state of the sperm that may be needed for penetration of egg jelly of the newt, Cynops pyrrhogaster.

    Science.gov (United States)

    Takahashi, Tomoe; Kutsuzawa, Megumi; Shiba, Kogiku; Takayama-Watanabe, Eriko; Inaba, Kazuo; Watanabe, Akihiko

    2013-09-01

    Activation state of sperm motility named "hyperactivation" enables mammalian sperm to progress through the oviductal matrix, although a similar state of sperm motility is unknown in non-mammalian vertebrates at fertilization. Here, we found a high motility state of the sperm in the newt Cynops pyrrhogaster. It was predominantly caused in egg jelly extract (JE) and characterized by a high wave velocity of the undulating membrane (UM) that was significantly higher at the posterior midpiece. An insemination assay suggested that the high motility state might be needed for sperm to penetrate the egg jelly, which is the accumulated oviductal matrix. Specific characteristics of the high motility state were completely abrogated by a high concentration of verapamil, which blocks the L-type and T-type voltage-dependent Ca(2+) channels (VDCCs). Mibefradil, a dominant blocker of T-type VDCCs, suppressed the wave of the UM at the posterior midpiece with separate wave propagation from both the anterior midpiece and the posterior principal piece. In addition, nitrendipine, a dominant L-type VDCC blocker, weakened the wave of the UM, especially in the anterior midpiece. Live Ca(2+) imaging showed that, compared with the intact sperm in the JE, the relative intracellular Ca(2+) level changed especially in the anterior and posterior ends of the midpiece of the blocker-treated sperm. These suggest that different types of Ca(2+) channels mediate the intracellular Ca(2+) level predominantly in the anterior and posterior ends of the midpiece to maintain the high motility state of the newt sperm.

  8. Simplification to abacavir/lamivudine + atazanavir maintains viral suppression and improves bone and renal biomarkers in ASSURE, a randomized, open label, non-inferiority trial.

    Directory of Open Access Journals (Sweden)

    David A Wohl

    groups. CONCLUSIONS: After 24 weeks, simplification to ABC/3TC+ATV from TDF/FTC+ATV/r maintained viral suppression was well-tolerated, and led to improvements in bone and renal biomarkers and HDL cholesterol. TRIAL REGISTRATION: ClinicalTrials.gov NCT01102972 GlaxoSmithKline Clinical Study Register #113734.

  9. A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties.

    Science.gov (United States)

    Wang, Meng-Yu; Nestvold, Janne; Rekdal, Øystein; Kvalheim, Gunnar; Fodstad, Øystein

    2017-02-09

    Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo.

  10. Identification of a distinct small cell population from human bone marrow reveals its multipotency in vivo and in vitro.

    Directory of Open Access Journals (Sweden)

    James Wang

    Full Text Available Small stem cells, such as spore-like cells, blastomere-like stem cells (BLSCs, and very-small embryonic-like stem cells (VSELs have been described in recent studies, although their multipotency in human tissues has not yet been confirmed. Here, we report the discovery of adult multipotent stem cells derived from human bone marrow, which we call StemBios (SB cells. These isolated SB cells are smaller than 6 ìm and are DAPI+ and Lgr5+ (Leucine-Rich Repeat Containing G Protein-Coupled Receptor 5. Because Lgr5 has been characterized as a stem cell marker in the intestine, we hypothesized that SB cells may have a similar function. In vivo cell tracking assays confirmed that SB cells give rise to three types of cells, and in vitro studies demonstrated that SB cells cultured in proprietary media are able to grow to 6-25 ìm in size. Once the SB cells have attached to the wells, they differentiate into different cell lineages upon exposure to specific differentiation media. We are the first to demonstrate that stem cells smaller than 6 ìm can differentiate both in vivo and in vitro. In the future, we hope that SB cells will be used therapeutically to cure degenerative diseases.

  11. A Distinct Subpopulation of Bone Marrow Mesenchymal Stem Cells, Muse Cells, Directly Commit to the Replacement of Liver Components.

    Science.gov (United States)

    Katagiri, H; Kushida, Y; Nojima, M; Kuroda, Y; Wakao, S; Ishida, K; Endo, F; Kume, K; Takahara, T; Nitta, H; Tsuda, H; Dezawa, M; Nishizuka, S S

    2016-02-01

    Genotyping graft livers by short tandem repeats after human living-donor liver transplantation (n = 20) revealed the presence of recipient or chimeric genotype cases in hepatocytes (6 of 17, 35.3%), sinusoidal cells (18 of 18, 100%), cholangiocytes (15 of 17, 88.2%) and cells in the periportal areas (7 of 8, 87.5%), suggesting extrahepatic cell involvement in liver regeneration. Regarding extrahepatic origin, bone marrow mesenchymal stem cells (BM-MSCs) have been suggested to contribute to liver regeneration but compose a heterogeneous population. We focused on a more specific subpopulation (1-2% of BM-MSCs), called multilineage-differentiating stress-enduring (Muse) cells, for their ability to differentiate into liver-lineage cells and repair tissue. We generated a physical partial hepatectomy model in immunodeficient mice and injected green fluorescent protein (GFP)-labeled human BM-MSC Muse cells intravenously (n = 20). Immunohistochemistry, fluorescence in situ hybridization and species-specific polymerase chain reaction revealed that they integrated into regenerating areas and expressed liver progenitor markers during the early phase and then differentiated spontaneously into major liver components, including hepatocytes (≈74.3% of GFP-positive integrated Muse cells), cholangiocytes (≈17.7%), sinusoidal endothelial cells (≈2.0%), and Kupffer cells (≈6.0%). In contrast, the remaining cells in the BM-MSCs were not detected in the liver for up to 4 weeks. These results suggest that Muse cells are the predominant population of BM-MSCs that are capable of replacing major liver components during liver regeneration.

  12. CREB-regulated transcription coactivator 1 enhances CREB-dependent gene expression in spinal cord to maintain the bone cancer pain in mice

    Science.gov (United States)

    Liang, Ying; Liu, Yue; Hou, Bailing; Zhang, Wei; Liu, Ming; Sun, Yu-E; Gu, Xiaoping

    2016-01-01

    Background cAMP response element binding protein (CREB)-dependent gene expression plays an important role in central sensitization. CREB-regulated transcription coactivator 1 (CRTC1) dramatically increases CREB-mediated transcriptional activity. Brain-derived neurotrophic factor, N-methyl-d-aspartate receptor subunit 2B, and miRNA-212/132, which are highly CREB responsive, function downstream from CREB/CRTC1 to mediate activity-dependent synaptic plasticity and in turn loops back to amplify CREB/CRTC1 signaling. This study aimed to investigate the role of spinal CRTC1 in the maintenance of bone cancer pain using an RNA interference method. Results Osteosarcoma cells were implanted into the intramedullary space of the right femurs of C3H/HeNCrlVr mice to induce bone cancer pain. Western blotting was applied to examine the expression of spinal phospho-Ser133 CREB and CRTC1. We further investigated effects of repeated intrathecal administration with Adenoviruses expressing CRTC1-small interfering RNA (siRNA) on nociceptive behaviors and on the upregulation of CREB/CRTC1-target genes associated with bone cancer pain. Inoculation of osteosarcoma cells induced progressive mechanical allodynia and spontaneous pain, and resulted in upregulation of spinal p-CREB and CRTC1. Repeated intrathecal administration with Adenoviruses expressing CRTC1-siRNA attenuated bone cancer–evoked pain behaviors, and reduced CREB/CRTC1-target genes expression in spinal cord, including BDNF, NR2B, and miR-212/132. Conclusions Upregulation of CRTC1 enhancing CREB-dependent gene transcription in spinal cord may play an important role in bone cancer pain. Inhibition of spinal CRTC1 expression reduced bone cancer pain. Interruption to the positive feedback circuit between CREB/CRTC1 and its targets may contribute to the analgesic effects. These findings may provide further insight into the mechanisms and treatment of bone cancer pain. PMID:27060162

  13. Mesenchymal stem cells maintain TGF-beta-mediated chondrogenic phenotype in alginate bead culture

    DEFF Research Database (Denmark)

    Mehlhorn, A T; Schmal, H; Kaiser, S

    2006-01-01

    This article addresses the stability of chondrogenic phenotype and the transdifferentiation potential of bone marrow-derived mesenchymal stem cells (MSCs) at distinct stages of differentiation. Differentiated MSCs were expected to maintain cartilage-like gene expression pattern in the absence of ...

  14. Arteriolar niches maintain haematopoietic stem cell quiescence.

    Science.gov (United States)

    Kunisaki, Yuya; Bruns, Ingmar; Scheiermann, Christoph; Ahmed, Jalal; Pinho, Sandra; Zhang, Dachuan; Mizoguchi, Toshihide; Wei, Qiaozhi; Lucas, Daniel; Ito, Keisuke; Mar, Jessica C; Bergman, Aviv; Frenette, Paul S

    2013-10-31

    Cell cycle quiescence is a critical feature contributing to haematopoietic stem cell (HSC) maintenance. Although various candidate stromal cells have been identified as potential HSC niches, the spatial localization of quiescent HSCs in the bone marrow remains unclear. Here, using a novel approach that combines whole-mount confocal immunofluorescence imaging techniques and computational modelling to analyse significant three-dimensional associations in the mouse bone marrow among vascular structures, stromal cells and HSCs, we show that quiescent HSCs associate specifically with small arterioles that are preferentially found in endosteal bone marrow. These arterioles are ensheathed exclusively by rare NG2 (also known as CSPG4)(+) pericytes, distinct from sinusoid-associated leptin receptor (LEPR)(+) cells. Pharmacological or genetic activation of the HSC cell cycle alters the distribution of HSCs from NG2(+) periarteriolar niches to LEPR(+) perisinusoidal niches. Conditional depletion of NG2(+) cells induces HSC cycling and reduces functional long-term repopulating HSCs in the bone marrow. These results thus indicate that arteriolar niches are indispensable for maintaining HSC quiescence.

  15. Distinct H3F3A and H3F3B driver mutations define chondroblastoma and giant cell tumor of bone.

    Science.gov (United States)

    Behjati, Sam; Tarpey, Patrick S; Presneau, Nadège; Scheipl, Susanne; Pillay, Nischalan; Van Loo, Peter; Wedge, David C; Cooke, Susanna L; Gundem, Gunes; Davies, Helen; Nik-Zainal, Serena; Martin, Sancha; McLaren, Stuart; Goody, Victoria; Goodie, Victoria; Robinson, Ben; Butler, Adam; Teague, Jon W; Halai, Dina; Khatri, Bhavisha; Myklebost, Ola; Baumhoer, Daniel; Jundt, Gernot; Hamoudi, Rifat; Tirabosco, Roberto; Amary, M Fernanda; Futreal, P Andrew; Stratton, Michael R; Campbell, Peter J; Flanagan, Adrienne M

    2013-12-01

    It is recognized that some mutated cancer genes contribute to the development of many cancer types, whereas others are cancer type specific. For genes that are mutated in multiple cancer classes, mutations are usually similar in the different affected cancer types. Here, however, we report exquisite tumor type specificity for different histone H3.3 driver alterations. In 73 of 77 cases of chondroblastoma (95%), we found p.Lys36Met alterations predominantly encoded in H3F3B, which is one of two genes for histone H3.3. In contrast, in 92% (49/53) of giant cell tumors of bone, we found histone H3.3 alterations exclusively in H3F3A, leading to p.Gly34Trp or, in one case, p.Gly34Leu alterations. The mutations were restricted to the stromal cell population and were not detected in osteoclasts or their precursors. In the context of previously reported H3F3A mutations encoding p.Lys27Met and p.Gly34Arg or p.Gly34Val alterations in childhood brain tumors, a remarkable picture of tumor type specificity for histone H3.3 driver alterations emerges, indicating that histone H3.3 residues, mutations and genes have distinct functions.

  16. Maintained hand function and forearm bone health 14 months after an in-home virtual-reality videogame hand telerehabilitation intervention in an adolescent with hemiplegic cerebral palsy.

    Science.gov (United States)

    Golomb, Meredith R; Warden, Stuart J; Fess, Elaine; Rabin, Bryan; Yonkman, Janell; Shirley, Bridget; Burdea, Grigore C

    2011-03-01

    Virtual reality videogames can be used to motivate rehabilitation, and telerehabilitation can be used to improve access to rehabilitation. These uses of technology to improve health outcomes are a burgeoning area of rehabilitation research. So far, there is a lack of reports of long-term outcomes of these types of interventions. The authors report a 15-year-old boy with hemiplegic cerebral palsy and epilepsy because of presumed perinatal stroke who improved his plegic hand function and increased his plegic forearm bone health during a 14-month virtual reality videogame hand telerehabilitation intervention. A total of 14 months after the intervention ended, repeat evaluation demonstrated maintenance of both increased hand function and forearm bone health. The implications of this work for the future of rehabilitation in children with neurological disabilities are discussed in this article.

  17. IKAROS expression in distinct bone marrow cell populations as a candidate biomarker for outcome with lenalidomide-dexamethasone therapy in multiple myeloma.

    Science.gov (United States)

    Bolomsky, Arnold; Hübl, Wolfgang; Spada, Stefano; Müldür, Ercan; Schlangen, Karin; Heintel, Daniel; Rocci, Alberto; Weißmann, Adalbert; Fritz, Veronique; Willheim, Martin; Zojer, Niklas; Palumbo, Antonio; Ludwig, Heinz

    2017-03-01

    Immunomodulatory drugs (IMiDs) are a cornerstone in the treatment of multiple myeloma (MM), but specific markers to predict outcome are still missing. Recent work pointed to a prognostic role for IMiD target genes (e.g. CRBN). Moreover, indirect activity of IMiDs on immune cells correlated with outcome, raising the possibility that cell populations in the bone marrow (BM) microenvironment could serve as biomarkers. We therefore analysed gene expression levels of six IMiD target genes in whole BM samples of 44 myeloma patients treated with lenalidomide-dexamethasone. Expression of CRBN (R = 0.30, P = .05), IKZF1 (R = 0.31, P = .04), IRF4 (R = 0.38, P = .01), MCT-1 (R = 0.30, P = .05), and CD147 (R = 0.38, P = .01), but not IKZF3 (R = -0.15, P = .34), was significantly associated with response. Interestingly, IKZF1 expression was elevated in BM environmental cells and thus selected for further investigation by multicolor flow cytometry. High IKAROS protein levels in total BM mononuclear cells (median OS 83.4 vs. 32.2 months, P = .02), CD19(+) B cells (median OS 71.1 vs. 32.2 months, P = .05), CD3(+) CD8(+) T cells (median OS 83.4 vs 19.0 months, P = .008) as well as monocytes (median OS 53.9 vs 18.0 months, P = .009) were associated with superior overall survival (OS). In contrast, IKAROS protein expression in MM cells was not predictive for OS. Our data therefore corroborate the central role of immune cells for the clinical activity of IMiDs and built the groundwork for prospective analysis of IKAROS protein levels in distinct cell populations as a potential biomarker for IMiD based therapies.

  18. Potential role of 20S proteasome in maintaining stem cell integrity of human bone marrow stromal cells in prolonged culture expansion

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Li, E-mail: luli7300@126.com [Department of Anatomy, Shanxi Medical University, Taiyuan 030001 (China); Song, Hui-Fang; Zhang, Wei-Guo; Liu, Xue-Qin; Zhu, Qian; Cheng, Xiao-Long; Yang, Gui-Jiao [Department of Anatomy, Shanxi Medical University, Taiyuan 030001 (China); Li, Ang [Department of Anatomy, University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Xiao, Zhi-Cheng, E-mail: zhicheng.xiao@monash.edu [Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical College, Kunming 650031 (China); Monash Immunology and Stem Cell Laboratories, Monash University, Clayton, Melbourne 3800 (Australia)

    2012-05-25

    Highlights: Black-Right-Pointing-Pointer Prolonged culture expansion retards proliferation and induces senescence of hBMSCs. Black-Right-Pointing-Pointer Reduced 20S proteasomal activity and expression potentially contribute to cell aging. Black-Right-Pointing-Pointer MG132-mediated 20S proteasomal inhibition induces senescence-like phenotype. Black-Right-Pointing-Pointer 18{alpha}-GA stimulates proteasomal activity and restores replicative senescence. Black-Right-Pointing-Pointer 18{alpha}-GA retains differentiation without affecting stem cell characterizations. -- Abstract: Human bone marrow stromal cells (hBMSCs) could be used in clinics as precursors of multiple cell lineages following proper induction. Such application is impeded by their characteristically short lifespan, together with the increasing loss of proliferation capability and progressive reduction of differentiation potential after the prolonged culture expansion. In the current study, we addressed the possible role of 20S proteasomes in this process. Consistent with prior reports, long-term in vitro expansion of hBMSCs decreased cell proliferation and increased replicative senescence, accompanied by reduced activity and expression of the catalytic subunits PSMB5 and PSMB1, and the 20S proteasome overall. Application of the proteasome inhibitor MG132 produced a senescence-like phenotype in early passages, whereas treating late-passage cells with 18{alpha}-glycyrrhetinic acid (18{alpha}-GA), an agonist of 20S proteasomes, delayed the senescence progress, enhancing the proliferation and recovering the capability of differentiation. The data demonstrate that activation of 20S proteasomes assists in counteracting replicative senescence of hBMSCs expanded in vitro.

  19. Distinct effects of pioglitazone and metformin on circulating sclerostin and biochemical markers of bone turnover in men with type 2 diabetes mellitus.

    NARCIS (Netherlands)

    Lierop, A.H. van; Hamdy, N.A.; Meer, R.W. van der; Jonker, J.T.; Lamb, H.J.; Rijzewijk, L.J.; Diamant, M.; Romijn, J.A.; Smit, J.W.A.; Papapoulos, S.E.

    2012-01-01

    OBJECTIVE: Patients with type 2 diabetes mellitus (T2DM) have an increased risk of fractures and thiazolidinediones (TZDs) increase this risk. TZDs stimulate the expression of sclerostin, a negative regulator of bone formation, in vitro. Abnormal sclerostin production may, therefore, be involved in

  20. Bone Health and Osteoporosis.

    Science.gov (United States)

    Lupsa, Beatrice C; Insogna, Karl

    2015-09-01

    Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone tissue leading to decreased bone strength and an increased risk of low-energy fractures. Central dual-energy X-ray absorptiometry measurements are the gold standard for determining bone mineral density. Bone loss is an inevitable consequence of the decrease in estrogen levels during and following menopause, but additional risk factors for bone loss can also contribute to osteoporosis in older women. A well-balanced diet, exercise, and smoking cessation are key to maintaining bone health as women age. Pharmacologic agents should be recommended in patients at high risk for fracture.

  1. Two distinct mechanisms mediate the involvement of bone marrow cells in islet remodeling: neogenesis of insulin-producing cells and support of islet recovery.

    Science.gov (United States)

    Iskovich, Svetlana; Goldenberg-Cohen, Nitza; Sadikov, Tamila; Yaniv, Isaac; Stein, Jerry; Askenasy, Nadir

    2015-01-01

    We have recently reported that small-sized bone marrow cells (BMCs) isolated by counterflow centrifugal elutriation and depleted of lineage markers (Fr25lin(-)) have the capacity to differentiate and contribute to regeneration of injured islets. In this study, we assess some of the characteristics of these cells compared to elutriated hematopoietic progenitors (R/O) and whole BMCs in a murine model of streptozotocin-induced chemical diabetes. The GFP(bright)CD45(+) progeny of whole BMCs and R/O progenitors progressively infiltrate the pancreas with evolution of donor chimerism; are found at islet perimeter, vascular, and ductal walls; and have a modest impact on islet recovery from injury. In contrast, Fr25lin(-) cells incorporate in the islets, convert to GFP(dim)CD45(-)PDX-1(+) phenotypes, produce proinsulin, and secrete insulin with significant contribution to stabilization of glucose homeostasis. The elutriated Fr25lin(-) cells express low levels of CD45 and are negative for SCA-1 and c-kit, as removal of cells expressing these markers did not impair conversion to produce insulin. BMCs mediate two synergistic mechanisms that contribute to islet recovery from injury: support of islet remodeling by hematopoietic cells and neogenesis of insulin-producing cells from stem cells.

  2. Recursive Distinctioning

    CERN Document Server

    Isaacson, Joel

    2016-01-01

    Recursive distinctioning (RD) is a name coined by Joel Isaacson in his original patent document describing how fundamental patterns of process arise from the systematic application of operations of distinction and description upon themselves. Recursive distinctioning means just what it says. A pattern of distinctions is given in a space based on a graphical structure (such as a line of print or a planar lattice or given graph). Each node of the graph is occupied by a letter from some arbitrary alphabet. A specialized alphabet is given that can indicate distinctions about neighbors of a given node. The neighbors of a node are all nodes that are connected to the given node by edges in the graph. The letters in the specialized alphabet (call it SA) are used to describe the states of the letters in the given graph and at each stage in the recursion, letters in SA are written at all nodes in the graph, describing its previous state. The recursive structure that results from the iteration of descriptions is called ...

  3. Arteriolar niches maintain haematopoietic stem cell quiescence

    Science.gov (United States)

    Kunisaki, Yuya; Bruns, Ingmar; Scheiermann, Christoph; Ahmed, Jalal; Pinho, Sandra; Zhang, Dachuan; Mizoguchi, Toshihide; Wei, Qiaozhi; Lucas, Daniel; Ito, Keisuke; Mar, Jessica C.; Bergman, Aviv; Frenette, Paul S.

    2013-01-01

    Cell cycle quiescence is a critical feature contributing to haematopoietic stem cell (HSC) maintenance. Although various candidate stromal cells have been identified as potential HSC niches, the spatial localization of quiescent HSCs in the bone marrow (BM) remains unclear. Here, using a novel approach that combines whole-mount confocal immunofluorescence imaging techniques and computational modelling to analyse significant tridimensional associations among vascular structures, stromal cells and HSCs, we show that quiescent HSCs associate specifically with small arterioles that are preferentially found in endosteal BM. These arterioles are ensheathed exclusively by rare NG2+ pericytes, distinct from sinusoid-associated LepR+ cells. Pharmacological or genetic activation of HSC cell cycle alters the distribution of HSCs from NG2+ peri-arteriolar niches to LepR+ peri-sinusoidal niches. Conditional depletion of NG2+ cells induces HSC cycling and reduces functional long-term repopulating HSCs in BM. These results thus indicate that arteriolar niches are indispensable to maintain HSC quiescence. PMID:24107994

  4. 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 ...

  5. Regulation of Bone Metabolism.

    Science.gov (United States)

    Shahi, Maryam; Peymani, Amir; Sahmani, Mehdi

    2017-04-01

    Bone is formed through the processes of endochondral and intramembranous ossification. In endochondral ossification primary mesenchymal cells differentiate to chondrocytes and then are progressively substituted by bone, while in intramembranous ossification mesenchymal stem cells (MSCs) differentiate directly into osteoblasts to form bone. The steps of osteogenic proliferation, differentiation, and bone homeostasis are controlled by various markers and signaling pathways. Bone needs to be remodeled to maintain integrity with osteoblasts, which are bone-forming cells, and osteoclasts, which are bone-degrading cells.In this review we considered the major factors and signaling pathways in bone formation; these include fibroblast growth factors (FGFs), bone morphogenetic proteins (BMPs), wingless-type (Wnt) genes, runt-related transcription factor 2 (RUNX2) and osteoblast-specific transcription factor (osterix or OSX).

  6. Regulation of Bone Metabolism

    Science.gov (United States)

    Shahi, Maryam; Peymani, Amir; Sahmani, Mehdi

    2017-01-01

    Bone is formed through the processes of endochondral and intramembranous ossification. In endochondral ossification primary mesenchymal cells differentiate to chondrocytes and then are progressively substituted by bone, while in intramembranous ossification mesenchymal stem cells (MSCs) differentiate directly into osteoblasts to form bone. The steps of osteogenic proliferation, differentiation, and bone homeostasis are controlled by various markers and signaling pathways. Bone needs to be remodeled to maintain integrity with osteoblasts, which are bone-forming cells, and osteoclasts, which are bone-degrading cells.In this review we considered the major factors and signaling pathways in bone formation; these include fibroblast growth factors (FGFs), bone morphogenetic proteins (BMPs), wingless-type (Wnt) genes, runt-related transcription factor 2 (RUNX2) and osteoblast-specific transcription factor (osterix or OSX). PMID:28367467

  7. A preliminary study of effects of immediate bone grafting at mandibular first molar fresh extraction socketon maintaining alveolar bone height in adult orthodontic patients%成人正畸患者减数下颌第一恒磨牙即刻植骨对于牙槽嵴保持作用的初步研究

    Institute of Scientific and Technical Information of China (English)

    陈启兴; 周治波; 周彦恒

    2014-01-01

    Objective To evaluate the effect of immediate bone graftingat fresh mandibular first molar extraction socket on maintain alveolar bone height during orthodontic treatment.Methods 32 adult orthodontic patients withmandibular first molars extraction treatment plan were selected.Thetotal of 40 molar extraction sites were divided into graft group and non-graft group randomly.All patients received orthodontic treatment 2weeks after extraction (with or without bone graft).Cone beam CT were taken before (T0)and one year after extraction(T1).Compare the changes of alveolar height and width of two groups by Invivo Dental 5.0 software.Results One year after orthodontic treatment,extraction spacesingraft group and non-graft group decreased by an average of 2.85 mm and 3.50 mm respectively.In graft group,the alveolar width at 3 mm and 6mrn level from alveolarcrest decreased by 0.71 mm and 0.39 mm.In non-graft group,the alveolar width at 3 mm,6 mm and 9 mm level from alveolarcrest decreased by 4.1 mm,2.4 mm and 1.1 mm.Paired t-test showed significant changes (P<0.01).The alveolar height in non-graft group reduced by 1.72 rnm,the difference is significant (P<0.01),while graft group has no significant difference.Conclusions For orthodontic patients with mandibular first molar extraction plan,imeediatebone grafting after extraction can delaythe resorption of the alveolar bone crest,facilitating long-distance space closure.%目的 评价减数下颌第一恒磨牙后即刻植骨对正畸治疗中牙槽嵴的保持效果.方法 选取32名需要减数下颌第一恒磨牙的成年正畸患者,共40个牙位.随机分成拔牙后即刻植骨与非植骨两组.拔牙(植骨)后,患者均进行常规正畸治疗.拍摄拔牙前(T0)、拔牙后一年(T1)的锥体束CT,采用Invivo Dental 5.0软件进行三维测量,比较两组T0~T1牙槽嵴高度、宽度的变化.结果 植骨组在拔牙后一年,距离牙槽嵴顶3mm、6mm处牙槽嵴宽度分别减小了0.71 mm,0.39 mm

  8. Clinical evaluation of the efficacy of a GTR membrane (HEALIGUIDE® and demineralised bone matrix (OSSEOGRAFT® as a space maintainer in the treatment of Miller′s Class I gingival recession

    Directory of Open Access Journals (Sweden)

    S Nanditha

    2011-01-01

    Full Text Available Background: Periodontal plastic surgical procedures aimed at coverage of exposed root surface have evolved into routine treatment modalities. The present study was designed to evaluate the effectiveness and predictability of using a collagen barrier along with a demineralized bone matrix in the treatment of recession defects in a single surgical procedure. Materials and Methods: Seventeen patients with Miller′s class I recession were treated with a combination of a collagen barrier used along with a bone graft and coronally advanced flap technique. Clinical parameters were recorded at baseline, 3 months, 6 months, and 9 months. Results: The study showed a highly significant reduction in the recession depth (70.29 ± 21.96% at the end of the study. This study showed that the use of this technique for recession coverage is highly predictable and highly esthetic root coverage can be obtained.

  9. Bone Biopsy

    Science.gov (United States)

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

  10. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

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

  11. Androgens and bone.

    Science.gov (United States)

    Vanderschueren, Dirk; Vandenput, Liesbeth; Boonen, Steven; Lindberg, Marie K; Bouillon, Roger; Ohlsson, Claes

    2004-06-01

    Loss of estrogens or androgens increases the rate of bone remodeling by removing restraining effects on osteoblastogenesis and osteoclastogenesis, and also causes a focal imbalance between resorption and formation by prolonging the lifespan of osteoclasts and shortening the lifespan of osteoblasts. Conversely, androgens, as well as estrogens, maintain cancellous bone mass and integrity, regardless of age or sex. Although androgens, via the androgen receptor (AR), and estrogens, via the estrogen receptors (ERs), can exert these effects, their relative contribution remains uncertain. Recent studies suggest that androgen action on cancellous bone depends on (local) aromatization of androgens into estrogens. However, at least in rodents, androgen action on cancellous bone can be directly mediated via AR activation, even in the absence of ERs. Androgens also increase cortical bone size via stimulation of both longitudinal and radial growth. First, androgens, like estrogens, have a biphasic effect on endochondral bone formation: at the start of puberty, sex steroids stimulate endochondral bone formation, whereas they induce epiphyseal closure at the end of puberty. Androgen action on the growth plate is, however, clearly mediated via aromatization in estrogens and interaction with ERalpha. Androgens increase radial growth, whereas estrogens decrease periosteal bone formation. This effect of androgens may be important because bone strength in males seems to be determined by relatively higher periosteal bone formation and, therefore, greater bone dimensions, relative to muscle mass at older age. Experiments in mice again suggest that both the AR and ERalpha pathways are involved in androgen action on radial bone growth. ERbeta may mediate growth-limiting effects of estrogens in the female but does not seem to be involved in the regulation of bone size in males. In conclusion, androgens may protect men against osteoporosis via maintenance of cancellous bone mass and

  12. Maintaining Learners’Motivation

    Institute of Scientific and Technical Information of China (English)

    SI Zi-han

    2015-01-01

    Foreign language learning is a complex process and its success is determined by a variety of factors. The prime one of them is motivation ,which, as everyone knows, could be controlled by external forces so as to be taken advantage of. Motivation could prompt the learner to have his own learning goals and let him finish his learning task autonomously. All of that shows the im⁃portance of maintaining learners’motivation. This paper will demonstrate not only the definition and the types of motivation, but al⁃so the methods that could be used to stimulate and maintain the motivation.

  13. Economy Maintains Good Health

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    China’s national economy has maintained rapid even growth in the first half of 2007, according to Xie Fuzhan, Commissioner of the National Bureau of Statistics. He was referring to major economic indicators of the January-June period that reveal that Chi

  14. Calcium, vitamin D, and your bones

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000490.htm Calcium, vitamin D, and your bones To use the sharing ... and maintain strong bones. How Much Calcium and Vitamin D do I Need? Amounts of calcium are ...

  15. Bone within a bone

    Energy Technology Data Exchange (ETDEWEB)

    Williams, H.J.; Davies, A.M. E-mail: wendy.turner@roh.nhs.uk; Chapman, S

    2004-02-01

    The 'bone within a bone' appearance is a well-recognized radiological term with a variety of causes. It is important to recognize this appearance and also to be aware of the differential diagnosis. A number of common conditions infrequently cause this appearance. Other causes are rare and some remain primarily of historical interest, as they are no longer encountered in clinical practice. In this review we illustrate some of the conditions that can give the bone within a bone appearance and discuss the physiological and pathological aetiology of each where known.

  16. Nuclear power plant maintainability.

    Science.gov (United States)

    Seminara, J L; Parsons, S O

    1982-09-01

    In the mid-1970s a general awareness of human factors engineering deficiencies associated with power plant control rooms took shape and the Electric Power Research Institute (EPRI) awarded the Lockheed Corporation a contract to review the human factors aspects of five representative operational control rooms and their associated simulators. This investigation revealed a host of major and minor deficiencies that assumed unforeseen dimensions in the post- Three Mile Island accident period. In the course of examining operational problems (Seminara et al, 1976) and subsequently the methods for overcoming such problems (Seminara et al, 1979, 1980) indications surfaced that power plants were far from ideal in meeting the needs of maintenance personnel. Accordingly, EPRI sponsored an investigation of the human factors aspects of power plant maintainability (Seminara, 1981). This paper provides an overview of the maintainability problems and issues encountered in the course of reviewing five nuclear power plants.

  17. Direct bonded space maintainers.

    Science.gov (United States)

    Santos, V L; Almeida, M A; Mello, H S; Keith, O

    1993-01-01

    The aim of this study was to evaluate clinically a bonded space maintainer, which would reduce chair-side time and cost. Sixty appliances were fabricated from 0.7 mm stainless steel round wire and bonded using light-cured composite to the two teeth adjacent to the site of extraction of a posterior primary tooth. Twenty males and sixteen females (age range 5-9-years-old) were selected from the Pedodontic clinic of the State University of Rio de Janeiro. The sixty space maintainers were divided into two groups according to the site in which they were placed: a) absent first primary molar and b) absent second primary molar. Impressions and study models were obtained prior to and 6 months after bonding the appliances. During this period only 8.3% of failures were observed, most of them from occlusal or facial trauma. Student t-test did not show statistically significant alterations in the sizes of the maintained spaces during the trial period.

  18. Bone repair and stem cells.

    Science.gov (United States)

    Ono, Noriaki; Kronenberg, Henry M

    2016-10-01

    Bones are an important component of vertebrates; they grow explosively in early life and maintain their strength throughout life. Bones also possess amazing capabilities to repair-the bone is like new without a scar after complete repair. In recent years, a substantial progress has been made in our understanding on mammalian bone stem cells. Mouse genetic models are powerful tools to understand the cell lineage, giving us better insights into stem cells that regulate bone growth, maintenance and repair. Recent findings about these stem cells raise new questions that require further investigations.

  19. Growth patterns of fossil vertebrates as deduced from bone microstructure: case studies from India

    Indian Academy of Sciences (India)

    S Ray; D Mukherjee; S Bandyopadhyay

    2009-11-01

    Bone microstructure is affected by ontogeny, phylogeny, biomechanics and environments. These aspects of life history of an extinct animal, especially its growth patterns, may be assessed as fossil bone generally maintains its histological integrity. Recent studies on the bone histology of fossil vertebrates from India encompass different types of temnospondyls and dicynodonts from different Permian and Triassic horizons. The examined taxa show that they had distinct bone histology and varied growth patterns. The Early Triassic trematosaurids had an overall fast growth, which contrasts with that of the Middle and Late Triassic temnospondyl taxa examined. The dicynodonts on the other hand, were characterized by an overall fast growth with periodic interruptions, variable growth rates dependent on ontogeny and indeterminate growth strategy. A comparative study encompassing several neotherapsid genera including the dicynodonts shows significant evolutionary trends towards determinate growth strategy and reduced developmental plasticity.

  20. Bone Biochemistry on the International Space Station

    Science.gov (United States)

    Smith, Scott M.; Heer, Martina; Zwart, Sara R.

    2016-01-01

    Bone biochemical measures provide valuable insight into the nature and time course of microgravity effects on bone during space flight, where imaging technology cannot be employed. Increased bone resorption is a hallmark of space flight, while markers of bone formation are typically unchanged or decreased. Recent studies (after the deployment to ISS of the advanced resistive exercise device, ARED), have documented that astronauts with good nutritional intake (e.g., maintenance of body mass), good vitamin D status, and exercise maintained bone mineral density. These data are encouraging, but crewmembers exercising on the ARED do have alterations in bone biochemistry, specifically, bone resorption is still increased above preflight levels, but bone formation is also significantly increased. While this bone remodeling raises questions about the strength of the resulting bone, however documents beneficial effects of nutrition and exercise in counteracting bone loss of space flight.

  1. Bone Markers

    Science.gov (United States)

    ... markers may be seen in conditions such as: Osteoporosis Paget disease Cancer that has spread to the bone (metastatic bone disease) Hyperparathyroidism Hyperthyroidism Osteomalacia in adults and rickets in children—lack of bone mineralization, ...

  2. Bone scan

    Science.gov (United States)

    ... legs, or spine fractures) Diagnose a bone infection (osteomyelitis) Diagnose or determine the cause of bone pain, ... 2015:chap 43. Read More Broken bone Metabolism Osteomyelitis Review Date 12/10/2015 Updated by: Jatin ...

  3. 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 ...

  4. 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 ...

  5. Maintaining Web Cache Coherency

    Directory of Open Access Journals (Sweden)

    2000-01-01

    Full Text Available Document coherency is a challenging problem for Web caching. Once the documents are cached throughout the Internet, it is often difficult to keep them coherent with the origin document without generating a new traffic that could increase the traffic on the international backbone and overload the popular servers. Several solutions have been proposed to solve this problem, among them two categories have been widely discussed: the strong document coherency and the weak document coherency. The cost and the efficiency of the two categories are still a controversial issue, while in some studies the strong coherency is far too expensive to be used in the Web context, in other studies it could be maintained at a low cost. The accuracy of these analysis is depending very much on how the document updating process is approximated. In this study, we compare some of the coherence methods proposed for Web caching. Among other points, we study the side effects of these methods on the Internet traffic. The ultimate goal is to study the cache behavior under several conditions, which will cover some of the factors that play an important role in the Web cache performance evaluation and quantify their impact on the simulation accuracy. The results presented in this study show indeed some differences in the outcome of the simulation of a Web cache depending on the workload being used, and the probability distribution used to approximate updates on the cached documents. Each experiment shows two case studies that outline the impact of the considered parameter on the performance of the cache.

  6. Mesenchymal Stromal Cells from Osteoarthritic Synovium Are a Distinct Population Compared to Their Bone-Marrow Counterparts regarding Surface Marker Distribution and Immunomodulation of Allogeneic CD4+ T-Cell Cultures.

    Science.gov (United States)

    Hagmann, Sebastien; Rimmele, Claudia; Bucur, Florin; Dreher, Thomas; Zeifang, Felix; Moradi, Babak; Gotterbarm, Tobias

    2016-01-01

    Introduction. The participation of an inflammatory joint milieu has been described in osteoarthritis (OA) pathogenesis. Mesenchymal stromal cells (MSCs) play an important role in modulating inflammatory processes. Based on previous studies in an allogeneic T-cell coculture model, we aimed at further determining the role of synovial MSCs in OA pathogenesis. Methods. Bone-marrow (BM) and synovial membrane (SM) MSCs from hip joints of late stage OA patients and CD4+ T-cells from healthy donors were analysed regarding surface marker expression before and after coculture. Proliferation upon CD3/CD28 stimulation and cytokine analyses were compared between MSCs. Results. SM-MSCs differed from BM-MSCs in several surface markers and their osteogenic differentiation potential. Cocultures of both MSCs with CD4+ T-cells resulted in recruitment of CD45RA+ FoxP3+ regulatory T-cells. Upon stimulation, only SM-MSCs suppressed CD4+ T-cell proliferation, while both SM-MSCs and BM-MSCs modified cytokine profiles through suppressing IL-2 and TNF-α as well as increasing IL-6 secretion. Conclusions. Synovial MSCs from OA joints are a unique fraction that can be distinguished from their bone-marrow derived counterparts. Their unique ability to suppress CD3/CD28 induced CD4+ T-cell proliferation makes them a potential target for future therapeutic approaches.

  7. Quantum Distinction: Quantum Distinctiones!

    OpenAIRE

    Zeps, Dainis

    2009-01-01

    10 pages; How many distinctions, in Latin, quantum distinctiones. We suggest approach of anthropic principle based on anthropic reference system which should be applied equally both in theoretical physics and in mathematics. We come to principle that within reference system of life subject of mathematics (that of thinking) should be equated with subject of physics (that of nature). For this reason we enter notions of series of distinctions, quantum distinction, and argue that quantum distinct...

  8. Modified bonded bridge space maintainer.

    Science.gov (United States)

    Liegeois, F; Limme, M

    1999-01-01

    The premature loss of primary teeth can create the need for space maintenance and restoration of function. This article presents a fixed bonded space maintainer, which allows space to be maintained with economy of dental tissues.

  9. Assessing optimal software architecture maintainability

    NARCIS (Netherlands)

    Bosch, Jan; Bengtsson, P.O.; Smedinga, Rein; Sousa, P; Ebert, J

    2000-01-01

    Over the last decade, several authors have studied the maintainability of software architectures. In particular, the assessment of maintainability has received attention. However, even when one has a quantitative assessment of the maintainability of a software architecture, one still does not have a

  10. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... of DXA Bone Densitometry? What is a Bone Density Scan (DXA)? Bone density scanning, also called dual-energy x-ray absorptiometry ( ... is today's established standard for measuring bone mineral density (BMD). An x-ray (radiograph) is a noninvasive ...

  11. Androgen and bone mass in men

    Institute of Scientific and Technical Information of China (English)

    AnnieW.C.Kung

    2003-01-01

    Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function,activity and lifespan through complex mechanisms. Also androgens increase periosteal bone apposition, resulting in larger bone size and thicker cortical bone in men. There is convincing evidence to show that aromatization to estrogens was an important pathway for mediating the action of testosterone on bone physiology. Estrogen is probably the dominant sex steroid regulating bone resorption in men, but both testosterone and estrogen are important in maintaining bone formation. ( Asian J Androl 2003 Jun; 5: 148-154)

  12. 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

  13. Parallel mechanisms suppress cochlear bone remodeling to protect hearing.

    Science.gov (United States)

    Jáuregui, Emmanuel J; Akil, Omar; Acevedo, Claire; Hall-Glenn, Faith; Tsai, Betty S; Bale, Hrishikesh A; Liebenberg, Ellen; Humphrey, Mary Beth; Ritchie, Robert O; Lustig, Lawrence R; Alliston, Tamara

    2016-08-01

    Bone remodeling, a combination of bone resorption and formation, requires precise regulation of cellular and molecular signaling to maintain proper bone quality. Whereas osteoblasts deposit and osteoclasts resorb bone matrix, osteocytes both dynamically resorb and replace perilacunar bone matrix. Osteocytes secrete proteases like matrix metalloproteinase-13 (MMP13) to maintain the material quality of bone matrix through perilacunar remodeling (PLR). Deregulated bone remodeling impairs bone quality and can compromise hearing since the auditory transduction mechanism is within bone. Understanding the mechanisms regulating cochlear bone provides unique ways to assess bone quality independent of other aspects that contribute to bone mechanical behavior. Cochlear bone is singular in its regulation of remodeling by expressing high levels of osteoprotegerin. Since cochlear bone expresses a key PLR enzyme, MMP13, we examined whether cochlear bone relies on, or is protected from, osteocyte-mediated PLR to maintain hearing and bone quality using a mouse model lacking MMP13 (MMP13(-/-)). We investigated the canalicular network, collagen organization, lacunar volume via micro-computed tomography, and dynamic histomorphometry. Despite finding defects in these hallmarks of PLR in MMP13(-/-) long bones, cochlear bone revealed no differences in these markers, nor hearing loss as measured by auditory brainstem response (ABR) or distortion product oto-acoustic emissions (DPOAEs), between wild type and MMP13(-/-) mice. Dynamic histomorphometry revealed abundant PLR by tibial osteocytes, but near absence in cochlear bone. Cochlear suppression of PLR corresponds to repression of several key PLR genes in the cochlea relative to long bones. These data suggest that cochlear bone uniquely maintains bone quality and hearing independent of MMP13-mediated osteocytic PLR. Furthermore, the cochlea employs parallel mechanisms to inhibit remodeling by osteoclasts and osteoblasts, and by

  14. Use of porous space maintainers in staged mandibular reconstruction.

    Science.gov (United States)

    Henslee, Allan M; Spicer, Patrick P; Shah, Sarita R; Tatara, Alexander M; Kasper, F Kurtis; Mikos, Antonios G; Wong, Mark E

    2014-05-01

    The success of mandibular reconstructions depends not only on restoring the form and function of lost bone but also on the preservation of the overlying soft tissue layer. In this case study, 5 porous polymethylmethacrylate space maintainers fabricated via patient-specific molds were implanted initially to maintain the vitality of the overlying oral mucosa during staged mandibular reconstructions. Three of the 5 patients healed well; the other 2 patients developed dehiscences, likely due to a thin layer of soft tissue overlying the implant. The results presented provide evidence that a larger investigation of space maintainers fabricated using this method is warranted.

  15. Bone health in cancer patients

    DEFF Research Database (Denmark)

    Coleman, R; Body, J J; Aapro, M

    2014-01-01

    There are three distinct areas of cancer management that make bone health in cancer patients of increasing clinical importance. First, bone metastases are common in many solid tumours, notably those arising from the breast, prostate and lung, as well as multiple myeloma, and may cause major...... morbidity including fractures, severe pain, nerve compression and hypercalcaemia. Through optimum multidisciplinary management of patients with bone metastases, including the use of bone-targeted treatments such as potent bisphosphonates or denosumab, it has been possible to transform the course of advanced...... cancer for many patients resulting in a major reduction in skeletal complications, reduced bone pain and improved quality of life. Secondly, many of the treatments we use to treat cancer patients have effects on reproductive hormones, which are critical for the maintenance of normal bone remodelling...

  16. Acidosis, hypoxia and bone.

    Science.gov (United States)

    Arnett, Timothy R

    2010-11-01

    Bone homeostasis is profoundly affected by local pH and oxygen tension. It has long been recognised that the skeleton contains a large reserve of alkaline mineral (hydroxyapatite), which is ultimately available to neutralise metabolic H(+) if acid-base balance is not maintained within narrow limits. Bone cells are extremely sensitive to the direct effects of pH: acidosis inhibits mineral deposition by osteoblasts but it activates osteoclasts to resorb bone and other mineralised tissues. These reciprocal responses act to maximise the availability of OH(-) ions from hydroxyapatite in solution, where they can buffer excess H(+). The mechanisms by which bone cells sense small pH changes are likely to be complex, involving ion channels and receptors in the cell membrane, as well as direct intracellular effects. The importance of oxygen tension in the skeleton has also long been known. Recent work shows that hypoxia blocks the growth and differentiation of osteoblasts (and thus bone formation), whilst strongly stimulating osteoclast formation (and thus bone resorption). Surprisingly, the resorptive function of osteoclasts is unimpaired in hypoxia. In vivo, tissue hypoxia is usually accompanied by acidosis due to reduced vascular perfusion and increased glycolytic metabolism. Thus, disruption of the blood supply can engender a multiple negative impact on bone via the direct actions of reduced pO(2) and pH on bone cells. These observations may contribute to our understanding of the bone disturbances that occur in numerous settings, including ageing, inflammation, fractures, tumours, anaemias, kidney disease, diabetes, respiratory disease and smoking.

  17. Pathologic bone tissues in a Turkey vulture and a nonavian dinosaur: implications for interpreting endosteal bone and radial fibrolamellar bone in fossil dinosaurs.

    Science.gov (United States)

    Chinsamy, Anusuya; Tumarkin-Deratzian, Allison

    2009-09-01

    We report on similar pathological bone microstructure in an extant turkey vulture (Cathartes aura) and a nonavian dinosaur from Transylvania. Both these individuals exhibit distinctive periosteal reactive bone deposition accompanied by endosteal bone deposits in the medullary cavity. Our findings have direct implications on the two novel bone tissues recently described among nonavian dinosaurs, radial fibrolamellar bone tissue and medullary bone tissue. On the basis of the observed morphology of the periosteal reactive bone in the turkey vulture and the Transylvanian dinosaur, we propose that the radial fibrolamellar bone tissues observed in mature dinosaurs may have had a pathological origin. Our analysis also shows that on the basis of origin, location, and morphology, pathologically derived endosteal bone tissue can be similar to medullary bone tissues described in nonavian dinosaurs. As such, we caution the interpretation of all endosteally derived bone tissue as homologous to avian medullary bone.

  18. Social conformity despite individual preferences for distinctiveness.

    Science.gov (United States)

    Smaldino, Paul E; Epstein, Joshua M

    2015-03-01

    We demonstrate that individual behaviours directed at the attainment of distinctiveness can in fact produce complete social conformity. We thus offer an unexpected generative mechanism for this central social phenomenon. Specifically, we establish that agents who have fixed needs to be distinct and adapt their positions to achieve distinctiveness goals, can nevertheless self-organize to a limiting state of absolute conformity. This seemingly paradoxical result is deduced formally from a small number of natural assumptions and is then explored at length computationally. Interesting departures from this conformity equilibrium are also possible, including divergence in positions. The effect of extremist minorities on these dynamics is discussed. A simple extension is then introduced, which allows the model to generate and maintain social diversity, including multimodal distinctiveness distributions. The paper contributes formal definitions, analytical deductions and counterintuitive findings to the literature on individual distinctiveness and social conformity.

  19. Distinctive skeletal dysplasia in Cockayne syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Silengo, M.C.; Franceschini, P.; Bianco, R.; Biagioli, M.; Pastorin, L.; Vista, N.; Baldassar, A.; Benso, L.

    1986-03-01

    Cockayne syndrome is a well-known autosomal recessive form of dwarfism with senile-like appearance. Skeletal changes such as flattening of vertebral bodies, ivory epiphyses and thickening of cranial vault, have been observed in some patients with this condition. We describe here a 5.5-year-old girl with the typical clinical signs of Cockayne syndrome and a distinctive form of bone dysplasia with major involvement of the spine.

  20. Computational visual distinctness metric

    NARCIS (Netherlands)

    Martínez-Baena, J.; Toet, A.; Fdez-Vidal, X.R.; Garrido, A.; Rodríguez-Sánchez, R.

    1998-01-01

    A new computational visual distinctness metric based on principles of the early human visual system is presented. The metric is applied to quantify (1) the visual distinctness of targets in complex natural scenes and (2) the perceptual differences between compressed and uncompressed images. The new

  1. Histone acetyltransferase cofactor Trrap is essential for maintaining the hematopoietic stem/progenitor cell pool.

    Science.gov (United States)

    Loizou, Joanna I; Oser, Gabriela; Shukla, Vivek; Sawan, Carla; Murr, Rabih; Wang, Zhao-Qi; Trumpp, Andreas; Herceg, Zdenko

    2009-11-15

    The pool of hematopoietic stem/progenitor cells, which provide life-long reconstitution of all hematopoietic lineages, is tightly controlled and regulated by self-renewal and apoptosis. Histone modifiers and chromatin states are believed to govern establishment, maintenance, and propagation of distinct patterns of gene expression in stem cells, however the underlying mechanism remains poorly understood. In this study, we identified a role for the histone acetytransferase cofactor Trrap in the maintenance of hematopietic stem/progenitor cells. Conditional deletion of the Trrap gene in mice resulted in ablation of bone marrow and increased lethality. This was due to the depletion of early hematopoietic progenitors, including hematopoietic stem cells, via a cell-autonomous mechanism. Analysis of purified bone marrow progenitors revealed that these defects are associated with induction of p53-independent apoptosis and deregulation of Myc transcription factors. Together, this study has identified a critical role for Trrap in the mechanism that maintains hematopoietic stem cells and hematopoietic system, and underscores the importance of Trrap and histone modifications in tissue homeostasis.

  2. Marshal: Maintaining Evolving Models Project

    Data.gov (United States)

    National Aeronautics and Space Administration — SIFT proposes to design and develop the Marshal system, a mixed-initiative tool for maintaining task models over the course of evolving missions. Marshal-enabled...

  3. Simple fixed functional space maintainer.

    Science.gov (United States)

    Goenka, Puneet; Sarawgi, Aditi; Marwah, Nikhil; Gumber, Parvind; Dutta, Samir

    2014-01-01

    Premature loss of a primary tooth is one of the most common etiology for malocclusion. Space maintainers are employed to prevent this complication. In anterior region, esthetics is an important concern along with function and space management. Fiber-reinforced composite (FRC) retained space maintainer solves all these purposes ef ficiently and ef fectively. In addition, the technique is simple and the appliance is very comfortable inside the oral cavity. Here is a case of premature loss of anterior primary tooth which was replaced by FRC retained esthetic functional space maintainer. The appliance was found to be functioning satisfactorily inside the oral cavity till the last visit (1 Year). How to cite this article: Goenka P, Sarawgi A, Marwah N, Gumber P, Dutta S. Simple Fixed Functional Space Maintainer. Int J Clin Pediatr Dent 2014;7(3):225-228.

  4. A Novel Polarization Maintaining Fiber

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    It introduces a novel elliptical jacket polarization maintaining fiber, whose SAP is like numeral "1". One preform can be drawn over 8km. Fiber's performances show that it is fit for fiber gyroscope and other sensors.

  5. A Novel Polarization Maintaining Fiber

    Institute of Scientific and Technical Information of China (English)

    Benjamin Xue

    2003-01-01

    It introduces a novel elliptical jacket polarization maintaining fiber, whose SAP is like numeral "1" One preform can be drawn over 8km. Fiber's performances show that it is fit for fiber gyroscope and other sensors.

  6. Simple Fixed Functional Space Maintainer

    OpenAIRE

    Goenka, Puneet; Sarawgi, Aditi; Marwah, Nikhil; Gumber, Parvind; Dutta, Samir

    2015-01-01

    ABSTRACT% Premature loss of a primary tooth is one of the most common etiology for malocclusion. Space maintainers are employed to prevent this complication. In anterior region, esthetics is an important concern along with function and space management. Fiber-reinforced composite (FRC) retained space maintainer solves all these purposes ef ficiently and ef fectively. In addition, the technique is simple and the appliance is very comfortable inside the oral cavity. Here is a case of premature ...

  7. Bone Metabolism on ISS Missions

    Science.gov (United States)

    Smith, S. M.; Heer, M. A.; Shackelford, L. C.; Zwart, S. R.

    2014-01-01

    Spaceflight-induced bone loss is associated with increased bone resorption (1, 2), and either unchanged or decreased rates of bone formation. Resistive exercise had been proposed as a countermeasure, and data from bed rest supported this concept (3). An interim resistive exercise device (iRED) was flown for early ISS crews. Unfortunately, the iRED provided no greater bone protection than on missions where only aerobic and muscular endurance exercises were available (4, 5). In 2008, the Advanced Resistive Exercise Device (ARED), a more robust device with much greater resistance capability, (6, 7) was launched to the ISS. Astronauts who had access to ARED, coupled with adequate energy intake and vitamin D status, returned from ISS missions with bone mineral densities virtually unchanged from preflight (7). Bone biochemical markers showed that while the resistive exercise and adequate energy consumption did not mitigate the increased bone resorption, bone formation was increased (7, 8). The typical drop in circulating parathyroid hormone did not occur in ARED crewmembers. In 2014, an updated look at the densitometry data was published. This study confirmed the initial findings with a much larger set of data. In 42 astronauts (33 male, 9 female), the bone mineral density response to flight was the same for men and women (9), and those with access to the ARED did not have the typical decrease in bone mineral density that was observed in early ISS crewmembers with access to the iRED (Figure 1) (7). Biochemical markers of bone formation and resorption responded similarly in men and women. These data are encouraging, and represent the first in-flight evidence in the history of human space flight that diet and exercise can maintain bone mineral density on long-duration missions. However, the maintenance of bone mineral density through bone remodeling, that is, increases in both resorption and formation, may yield a bone with strength characteristics different from those

  8. Properties of deproteinized bone for reparation of big segmental defect in long bone

    Institute of Scientific and Technical Information of China (English)

    JIAN Yue-kui; TIAN Xiao-bin; LI Bo; QIU Bing; ZHOU Zuo-jia; YANG Zheng; LI Qi-hong

    2008-01-01

    Objective: To explore suitable scaffold material for big segmental long bone defect by studying the properties of the prepared deproteinized bone. Methods: Cancellated bone were made as 30 mm ×3 mm ×3 mm bone blocks from inferior extremity of pig femur along bone trabecula. The deproteinized bone was prepared with an improved method. Their morphological features, components, cell compatibility, mechanical and immunological properties were investigated respectively. Results: Deproteinized bone maintained natural re ticular pore system. The main organic material is collagen Ⅰand inorganic composition is hydroxyapatite. It has good mechanical properties, cell adhesion rate and histocompatibility. Conlusion: This deproteinized bone can be applicable as scaffold for reparation of big segmental defect in long bone.

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

    Science.gov (United States)

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

    2016-01-01

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

  10. Bone cutting.

    Science.gov (United States)

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

    1991-02-01

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

  11. Substance, Reality, and Distinctness

    Directory of Open Access Journals (Sweden)

    Boris Hennig

    2008-04-01

    Full Text Available Descartes claims that God is a substance, and that mind and body are two different and separable substances. This paper provides some background that renders these claims intelligible. For Descartes, that something is real means it can exist in separation, and something is a substance if it does not depend on other substances for its existence. Further, separable objects are correlates of distinct ideas, for an idea is distinct (in an objective sense if its object may be easily and clearly separated from everything that is not its object. It follows that if our idea of God is our most distinct idea, as Descartes claims, then God must be a substance in the Cartesian sense of the term. Also, if we can have an idea of a thinking subject which does not in any sense refer to bodily things, and if bodily things are substances, then mind and body must be two different substances.

  12. Studies on the mechanisms underlying the transfer of calcium and phosphate from bone to blood

    Energy Technology Data Exchange (ETDEWEB)

    Brommage, Robert J. Jr.

    1978-01-01

    The skeleton is recognized as a crucial organ in the minute-to-minute regulation of the blood levels of calcium and phosphate. The fluxes of calcium and phosphate to and from bone greatly exceed the entry and exit of these ions occurring in the intestine and kidneys. Parathyroid hormone, calcitonin, and 1,25-dihydroxyvitamin D/sub 3/ (1,25-(OH)/sub 2/D/sub 3/ are known to influence the transfer of calcium and phosphate from bone to blood. Three mechanisms have been proposed to explain the hormonal control of the calcium and phosphate effluxes from bone. The concept of a bone membrane maintaining a distinct bone extracellular fluid composition has led to the pump and pH gradient theories. An alternate solubilizer theory proposes that bone cells secrete a substance which increases the solubility of the bone mineral. The bone membrane concept was originally proposed to explain the presence of the apparent anomalously high concentrations of potassium in the bone extracellular fluid. However, the available evidence does not allow an unambiguous decision concerning the presence of a bone membrane. Calvarial lactate production was unaltered by 1,25-(OH)/sub 2/D/sub 3/ treatment and consequently 1,25-(OH)/sub 2/D/sub 3/ does not appear to promote the mobilization of bone mineral through a lactate-mediated pH gradient mechanism. 1,25-(OH)/sub 2/D/sub 3/ did increase the solubility of non-vital bone, clearly demonstrating that the solubilizer mechanism is at least partially responsible for the mobilization of bone mineral and the regulation of blood levels of calcium and phosphate. Vitamin D-deficient female rats fed a 0.2% calcium, 0.4% phosphorous diet and supplemented with daily injections of 0.75 pmole of 1,25-(OH)/sub 2/D/sub 3/ were shown to be capable of bearing young. When the injections of 1,25-(OH)/sub 2/D/sub 3/ were terminated at delivery, the dams and pups showed signs of vitamin D deficiency approximately one week later.

  13. Bulkloading and Maintaining XML Documents

    NARCIS (Netherlands)

    Schmidt, A.R.; Kersten, M.L.

    2002-01-01

    The popularity of XML as a exchange and storage format brings about massive amounts of documents to be stored, maintained and analyzed -- a challenge that traditionally has been tackled with Database Management Systems (DBMS). To open up the content of XML documents to analysis with declarative quer

  14. Developing Distinctive Degrees

    Science.gov (United States)

    Goodchild, Lester F.; Chambers, Crystal Renée; Freeman, Sydney, Jr.

    2016-01-01

    Understanding one's competitive stance in a globally competitive environment provides the requisite awareness to maintain both competitive edge and institutional responsiveness. In this chapter, three case studies are presented to provide examples of ways in which strategic scanning can enhance the academic program development process and how…

  15. Fibrillin microfibrils in bone physiology.

    Science.gov (United States)

    Smaldone, Silvia; Ramirez, Francesco

    2016-01-01

    The severe skeletal abnormalities associated with Marfan syndrome (MFS) and congenital contractural arachnodactyly (CCA) underscore the notion that fibrillin assemblies (microfibrils and elastic fibers) play a critical role in bone formation and function in spite of representing a low abundance component of skeletal matrices. Studies of MFS and CCA mice have correlated the skeletal phenotypes of these mutant animals with distinct pathophysiological mechanisms that reflect the contextual contribution of fibrillin-1 and -2 scaffolds to TGFβ and BMP signaling during bone patterning, growth and metabolism. Illustrative examples include the unique role of fibrillin-2 in regulating BMP-dependent limb patterning and the distinct impact of the two fibrillin proteins on the commitment and differentiation of marrow mesenchymal stem cells. Collectively, these findings have important implication for our understanding of the pathophysiological mechanisms that drive age- and injury-related processes of bone degeneration.

  16. Bone x-ray

    Science.gov (United States)

    ... or broken bone Bone tumors Degenerative bone conditions Osteomyelitis (inflammation of the bone caused by an infection) ... Multiple myeloma Osgood-Schlatter disease Osteogenesis imperfecta Osteomalacia Osteomyelitis Paget disease of the bone Rickets X-ray ...

  17. Disturbance maintains alternative biome states.

    Science.gov (United States)

    Dantas, Vinícius de L; Hirota, Marina; Oliveira, Rafael S; Pausas, Juli G

    2016-01-01

    Understanding the mechanisms controlling the distribution of biomes remains a challenge. Although tropical biome distribution has traditionally been explained by climate and soil, contrasting vegetation types often occur as mosaics with sharp boundaries under very similar environmental conditions. While evidence suggests that these biomes are alternative states, empirical broad-scale support to this hypothesis is still lacking. Using community-level field data and a novel resource-niche overlap approach, we show that, for a wide range of environmental conditions, fire feedbacks maintain savannas and forests as alternative biome states in both the Neotropics and the Afrotropics. In addition, wooded grasslands and savannas occurred as alternative grassy states in the Afrotropics, depending on the relative importance of fire and herbivory feedbacks. These results are consistent with landscape scale evidence and suggest that disturbance is a general factor driving and maintaining alternative biome states and vegetation mosaics in the tropics.

  18. Skeletal Blood Flow in Bone Repair and Maintenance

    Institute of Scientific and Technical Information of China (English)

    Ryan E.Tomlinson; Matthew J.Silva

    2013-01-01

    Bone is a highly vascularized tissue, although this aspect of bone is often overlooked. In this article, the importance of blood flow in bone repair and regeneration will be reviewed. First, the skeletal vascular anato-my, with an emphasis on long bones, the distinct mechanisms for vascularizing bone tissue, and methods for remodeling existing vasculature are discussed. Next, techniques for quantifying bone blood flow are briefly summarized. Finally, the body of experimental work that demonstrates the role of bone blood flow in fracture healing, distraction osteogenesis, osteoporosis, disuse osteopenia, and bone grafting is examined. These results illustrate that adequate bone blood flow is an important clinical consideration, particularly during bone regeneration and in at-risk patient groups.

  19. NMG documentation, part 3: maintainer`s guide

    Energy Technology Data Exchange (ETDEWEB)

    Fritsch, F.N.; Dickinson, R.P. Jr.

    1996-07-01

    This is the third of a three-part report documenting NMG, the Numerical Mathematics Guide. Part I is aimed at the user of the systenL It contains an introduction, with an out- line of the complete report, and Chapter 1, User`s Point of View. Part II is aimed at the programmer and contains Chapter 2, How It Works. Part III is aimed at the maintainer of NMG and contains Chapter 3, Maintenance, and Chapter 4, Validation. Because its contents are so specialized, Part III will receive only limited distribution. Note that each chapter has its own page numbering and table of contents.

  20. [Fractures of carpal bones].

    Science.gov (United States)

    Lögters, T; Windolf, J

    2016-10-01

    Fractures of the carpal bones are uncommon. On standard radiographs fractures are often not recognized and a computed tomography (CT) scan is the diagnostic method of choice. The aim of treatment is to restore pain-free and full functioning of the hand. A distinction is made between stable and unstable carpal fractures. Stable non-displaced fractures can be treated conservatively. Unstable and displaced fractures have an increased risk of arthritis and non-union and should be stabilized by screws or k‑wires. If treated adequately, fractures of the carpal bones have a good prognosis. Unstable and dislocated fractures have an increased risk for non-union. The subsequent development of carpal collapse with arthrosis is a severe consequence of non-union, which has a heterogeneous prognosis.

  1. Bone balance within a cortical BMU: local controls of bone resorption and formation.

    Directory of Open Access Journals (Sweden)

    David W Smith

    Full Text Available Maintaining bone volume during bone turnover by a BMU is known as bone balance. Balance is required to maintain structural integrity of the bone and is often dysregulated in disease. Consequently, understanding how a BMU controls bone balance is of considerable interest. This paper develops a methodology for identifying potential balance controls within a single cortical BMU. The theoretical framework developed offers the possibility of a directed search for biological processes compatible with the constraints of balance control. We first derive general control constraint equations and then introduce constitutive equations to identify potential control processes that link key variables that describe the state of the BMU. The paper describes specific local bone volume balance controls that may be associated with bone resorption and bone formation. Because bone resorption and formation both involve averaging over time, short-term fluctuations in the environment are removed, leaving the control systems to manage deviations in longer-term trends back towards their desired values. The length of time for averaging is much greater for bone formation than for bone resorption, which enables more filtering of variability in the bone formation environment. Remarkably, the duration for averaging of bone formation may also grow to control deviations in long-term trends of bone formation. Providing there is sufficient bone formation capacity by osteoblasts, this leads to an extraordinarily robust control mechanism that is independent of either osteoblast number or the cellular osteoid formation rate. A complex picture begins to emerge for the control of bone volume. Different control relationships may achieve the same objective, and the 'integration of information' occurring within a BMU may be interpreted as different sets of BMU control systems coming to the fore as different information is supplied to the BMU, which in turn leads to different observable

  2. Bone balance within a cortical BMU: local controls of bone resorption and formation.

    Science.gov (United States)

    Smith, David W; Gardiner, Bruce S; Dunstan, Colin

    2012-01-01

    Maintaining bone volume during bone turnover by a BMU is known as bone balance. Balance is required to maintain structural integrity of the bone and is often dysregulated in disease. Consequently, understanding how a BMU controls bone balance is of considerable interest. This paper develops a methodology for identifying potential balance controls within a single cortical BMU. The theoretical framework developed offers the possibility of a directed search for biological processes compatible with the constraints of balance control. We first derive general control constraint equations and then introduce constitutive equations to identify potential control processes that link key variables that describe the state of the BMU. The paper describes specific local bone volume balance controls that may be associated with bone resorption and bone formation. Because bone resorption and formation both involve averaging over time, short-term fluctuations in the environment are removed, leaving the control systems to manage deviations in longer-term trends back towards their desired values. The length of time for averaging is much greater for bone formation than for bone resorption, which enables more filtering of variability in the bone formation environment. Remarkably, the duration for averaging of bone formation may also grow to control deviations in long-term trends of bone formation. Providing there is sufficient bone formation capacity by osteoblasts, this leads to an extraordinarily robust control mechanism that is independent of either osteoblast number or the cellular osteoid formation rate. A complex picture begins to emerge for the control of bone volume. Different control relationships may achieve the same objective, and the 'integration of information' occurring within a BMU may be interpreted as different sets of BMU control systems coming to the fore as different information is supplied to the BMU, which in turn leads to different observable BMU behaviors.

  3. Stem cell property of postmigratory cranial neural crest cells and their utility in alveolar bone regeneration and tooth development.

    Science.gov (United States)

    Chung, Il-Hyuk; Yamaza, Takayoshi; Zhao, Hu; Choung, Pill-Hoon; Shi, Songtao; Chai, Yang

    2009-04-01

    The vertebrate neural crest is a multipotent cell population that gives rise to a variety of different cell types. We have discovered that postmigratory cranial neural crest cells (CNCCs) maintain mesenchymal stem cell characteristics and show potential utility for the regeneration of craniofacial structures. We are able to induce the osteogenic differentiation of postmigratory CNCCs, and this differentiation is regulated by bone morphogenetic protein (BMP) and transforming growth factor-beta signaling pathways. After transplantation into a host animal, postmigratory CNCCs form bone matrix. CNCC-formed bones are distinct from bones regenerated by bone marrow mesenchymal stem cells. In addition, CNCCs support tooth germ survival via BMP signaling in our CNCC-tooth germ cotransplantation system. Thus, we conclude that postmigratory CNCCs preserve stem cell features, contribute to craniofacial bone formation, and play a fundamental role in supporting tooth organ development. These findings reveal a novel function for postmigratory CNCCs in organ development, and demonstrate the utility of these CNCCs in regenerating craniofacial structures.

  4. The Rho-GEF Kalirin regulates bone mass and the function of osteoblasts and osteoclasts

    OpenAIRE

    2013-01-01

    Bone homeostasis is maintained by the balance between bone resorption by osteoclasts and bone formation by osteoblasts. Dysregulation in the activity of the bone cells can lead to osteoporosis, a disease characterized by low bone mass and an increase in bone fragility and risk of fracture. Kalirin is a novel GTP-exchange factor protein that has been shown to play a role in cytoskeletal remodeling and dendritic spine formation in neurons. We examined Kalirin expression in skeletal tissue and f...

  5. 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....

  6. Bone graft

    Science.gov (United States)

    ... around the area. The bone graft can be held in place with pins, plates, or screws. Why ... Orthopaedic Surgery, San Francosco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the ...

  7. Control Inflation while Maintain Growth

    Institute of Scientific and Technical Information of China (English)

    Yang Junsheng

    2008-01-01

    @@ Dragged by the U.S.subprime crisis and the soaring oil price, the global economy is slowing down,causing problems to China, the country which has continuously achieved miraculous economic growth.Apart from the accumulation of high inflation and risks of overheated economy, China is attacked by serious natural disasters ever since the beginning of 2008,including the snow disaster, the earthquake and the flood.It is obviously that China's priority now is to bring inflation under control so as to maintain the stable growth of economy.

  8. Maintaining a Distinction Between Possible and Impossible Topics of Conversation in the Outpatient Respiratory Medical Clinic

    DEFF Research Database (Denmark)

    Birgitte Skov Jensen, Lone; Larsen, Kristian; Konradsen, Hanne

    2016-01-01

    The aim of this study is to generate a grounded theory explaining patterns of behavior among health care professionals (HCPs) during interactions with patients in outpatient respiratory medical clinics. The findings suggest that the HCPs managed contradictory expectations to the interaction...

  9. The epidermis comprises autonomous compartments maintained by distinct stem cell populations

    DEFF Research Database (Denmark)

    Page, Mahalia E; Lombard, Patrick; Ng, Felicia

    2013-01-01

    populations. In contrast, upon wounding, stem cell progeny from multiple compartments acquire lineage plasticity and make permanent contributions to regenerating tissue. We further show that oncogene activation in Lrig1(+ve) cells drives hyperplasia but requires auxiliary stimuli for tumor formation...

  10. Low Bone Density

    Science.gov (United States)

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

  11. A short-term zinc-deficient diet decreases bone formation through down-regulated BMP2 in rat bone.

    Science.gov (United States)

    Suzuki, Takako; Katsumata, Shin-Ichi; Matsuzaki, Hiroshi; Suzuki, Kazuharu

    2016-07-01

    We investigated the effects of a short-term dietary zinc deficiency on bone metabolism. Zinc deficiency increased the mRNA expression of zinc uptake transporters such as Zip1, Zip13, and Zip14 in bone. However, zinc deficiency might not maintain zinc storage in bone, resulting in a decrease in bone formation through downregulation of the expression levels of osteoblastogenesis-related genes.

  12. Limb bone morphology, bone strength, and cursoriality in lagomorphs.

    Science.gov (United States)

    Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

    2014-10-01

    The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which 'cursorial specialization' affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and μCT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high 'displacement advantage', permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with increasing

  13. Bone marrow transplant

    Science.gov (United States)

    Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; Umbilical ...

  14. [Bone and Men's Health. Bone selective androgen receptor modulators].

    Science.gov (United States)

    Furuya, Kazuyuki

    2010-02-01

    Androgen, one of the sex steroid hormones shows various biological activities on the corresponding various tissues. Many efforts to produce novel drug materials maintaining a desired biological activity with an adequate tissue selectivity, which is so-called selective androgen receptor modulators (SARMs) , are being performed. As one of such efforts, studies on SARMs against bone tissues which possess a significant potential to stimulate a bone formation with reducing undesirable androgenic virilizing activities are in progress all over the world. This review focuses on the research and development activities of such SARMs and discuses their usefulness for the treatment of osteoporosis.

  15. Maintaining consistency in distributed systems

    Science.gov (United States)

    Birman, Kenneth P.

    1991-01-01

    In systems designed as assemblies of independently developed components, concurrent access to data or data structures normally arises within individual programs, and is controlled using mutual exclusion constructs, such as semaphores and monitors. Where data is persistent and/or sets of operation are related to one another, transactions or linearizability may be more appropriate. Systems that incorporate cooperative styles of distributed execution often replicate or distribute data within groups of components. In these cases, group oriented consistency properties must be maintained, and tools based on the virtual synchrony execution model greatly simplify the task confronting an application developer. All three styles of distributed computing are likely to be seen in future systems - often, within the same application. This leads us to propose an integrated approach that permits applications that use virtual synchrony with concurrent objects that respect a linearizability constraint, and vice versa. Transactional subsystems are treated as a special case of linearizability.

  16. A physical mechanism for coupling bone resorption and formation in adult human bone

    DEFF Research Database (Denmark)

    Andersen, Thomas Levin; Sondergaard, Teis Esben; Skorzynska, Katarzyna Ewa

    2009-01-01

    During skeletal remodeling, pre-osteoclasts and pre-osteoblasts are targeted to critical sites of the bone to resorb and reconstruct bone matrix, respectively. Coordination of site-specific recruitment of these two cell types is a prerequisite to maintain the specific architecture of each bone...... within strict limits throughout adult life. Here, we determined that the bone marrow microanatomy adjacent to remodeling areas is a central player in this process. By using histomorphometry and multiple immunostainings, we demonstrated in biopsies exhibiting coupled bone resorption and formation...... that osteoclasts and osteoblasts on the bone surface were always covered by a canopy of flat cells expressing osteoblast markers. In contrast, in biopsies in which this canopy was disrupted, bone formation was deficient. Three-dimensional visualizations revealed that this canopy covered the entire remodeling site...

  17. Bone mineral content and bone metabolism in young adults with severe periodontitis

    DEFF Research Database (Denmark)

    Wowern von, N.; Westergaard, J.; Kollerup, G.

    2001-01-01

    Bone loss, bone markers, bone metabolism, bone mineral content, osteoporosis, severe periodontitis......Bone loss, bone markers, bone metabolism, bone mineral content, osteoporosis, severe periodontitis...

  18. [Bone transplant].

    Science.gov (United States)

    San Julián, M; Valentí, A

    2006-01-01

    We describe the methodology of the Bone and Soft Tissue Bank, from extraction and storage until use. Since the year 1986, with the creation of the Bone Bank in the University Clinic of Navarra, more than 3,000 grafts have been used for very different types of surgery. Bone grafts can be classified into cortical and spongy; the former are principally used in surgery to save tumour patients, in large post-traumatic reconstructions and in replacement surgery where there are massive bone defects and a structural support is required. The spongy grafts are the most used due to their numerous indications; they are especially useful in filling cavities that require a significant quantity of graft when the autograft is insufficient, or as a complement. They are also of special help in treating fractures when there is bone loss and in the treatment of delays in consolidation and pseudoarthrosis in little vascularized and atrophic zones. They are also used in prosthetic surgery against the presence of cavity type defects. Allografts of soft tissues are specially recognised in multiple ligament injuries that require reconstructions. Nowadays, the most utilised are those employed in surgery of the anterior cruciate ligament although they can be used for filling any ligament or tendon defect. The principal difficulties of the cortical allografts are in the consolidation of the ends with the bone itself and in tumour surgery, given that these are patients immunodepressed by the treatment, the incidence of infection is increased with respect to spongy grafts and soft tissues, which is irrelevant. In short, the increasingly widespread use of allografts is an essential therapeutic weapon in orthopaedic surgery and traumatology. It must be used by expert hands.

  19. Bone phenotypes of P2 receptor knockout mice

    DEFF Research Database (Denmark)

    Orriss, Isabel; Syberg, Susanne; Wang, Ning;

    2011-01-01

    The action of extracellular nucleotides is mediated by ionotropic P2X receptors and G-protein coupled P2Y receptors. The human genome contains 7 P2X and 8 P2Y receptor genes. Knockout mice strains are available for most of them. As their phenotypic analysis is progressing, bone abnormalities have...... been observed in an impressive number of these mice: distinct abnormalities in P2X7-/- mice, depending on the gene targeting construct and the genetic background, decreased bone mass in P2Y1-/- mice, increased bone mass in P2Y2-/- mice, decreased bone resorption in P2Y6-/- mice, decreased bone...... formation and bone resorption in P2Y13-/- mice. These findings demonstrate the unexpected importance of extracellular nucleotide signalling in the regulation of bone metabolism via multiple P2 receptors and distinct mechanisms involving both osteoblasts and osteoclasts....

  20. Bone biopsy (image)

    Science.gov (United States)

    A bone biopsy is performed by making a small incision into the skin. A biopsy needle retrieves a sample of bone and it ... examination. The most common reasons for bone lesion biopsy are to distinguish between benign and malignant bone ...

  1. Bone lesion biopsy

    Science.gov (United States)

    Bone biopsy; Biopsy - bone ... needle is gently pushed and twisted into the bone. Once the sample is obtained, the needle is ... sample is sent to a lab for examination. Bone biopsy may also be done under general anesthesia ...

  2. Facts about Broken Bones

    Science.gov (United States)

    ... Room? What Happens in the Operating Room? Broken Bones KidsHealth > For Kids > Broken Bones Print A A ... sticking through the skin . What Happens When a Bone Breaks? It hurts to break a bone! It's ...

  3. Calcium and bones

    Science.gov (United States)

    Bone strength and calcium ... calcium (as well as phosphorus) to make healthy bones. Bones are the main storage site of calcium in ... your body does not absorb enough calcium, your bones can get weak or will not grow properly. ...

  4. Broken Bones (For Parents)

    Science.gov (United States)

    ... Feeding Your 1- to 2-Year-Old Broken Bones KidsHealth > For Parents > Broken Bones Print A A ... bone fragments in place. When Will a Broken Bone Heal? Fractures heal at different rates, depending upon ...

  5. Understanding Bone Strength Is Not Enough.

    Science.gov (United States)

    Hernandez, Christopher J; van der Meulen, Marjolein Ch

    2017-01-09

    Increases in fracture risk beyond what are expected from bone mineral density (BMD) are often attributed to poor "bone quality," such as impaired bone tissue strength. Recent studies, however, have highlighted the importance of tissue material properties other than strength, such as fracture toughness. Here we review the concepts behind failure properties other than strength and the physical mechanisms through which they cause mechanical failure: strength describes failure from a single overload; fracture toughness describes failure from a modest load combined with a preexisting flaw or damage; and fatigue strength describes failure from thousands to millions of cycles of small loads. In bone, these distinct failure mechanisms appear to be more common in some clinical fractures than others. For example, wrist fractures are usually the result of a single overload, the failure mechanism dominated by bone strength, whereas spinal fractures are rarely the result of a single overload, implicating multiple loading cycles and increased importance of fatigue strength. The combination of tissue material properties and failure mechanisms that lead to fracture represent distinct mechanistic pathways, analogous to molecular pathways used to describe cell signaling. Understanding these distinct mechanistic pathways is necessary because some characteristics of bone tissue can increase fracture risk by impairing fracture toughness or fatigue strength without impairing bone tissue strength. Additionally, mechanistic pathways to failure associated with fracture toughness and fatigue involve multiple loading events over time, raising the possibility that a developing fracture could be detected and interrupted before overt failure of a bone. Over the past two decades there have been substantial advancements in fracture prevention by understanding bone strength and fractures caused by a single load, but if we are to improve fracture risk prevention beyond what is possible now, we must

  6. Vitamin D and Bone Disease

    Directory of Open Access Journals (Sweden)

    S. Christodoulou

    2013-01-01

    Full Text Available Vitamin D is important for normal development and maintenance of the skeleton. Hypovitaminosis D adversely affects calcium metabolism, osteoblastic activity, matrix ossification, bone remodeling and bone density. It is well known that Vit. D deficiency in the developing skeleton is related to rickets, while in adults is related to osteomalacia. The causes of rickets include conditions that lead to hypocalcemia and/or hypophosphatemia, either isolated or secondary to vitamin D deficiency. In osteomalacia, Vit. D deficiency leads to impairment of the mineralisation phase of bone remodeling and thus an increasing amount of the skeleton being replaced by unmineralized osteoid. The relationship between Vit. D and bone mineral density and osteoporosis are still controversial while new evidence suggests that Vit. D may play a role in other bone conditions such as osteoarthritis and stress fractures. In order to maintain a “good bone health” guidelines concerning the recommended dietary intakes should be followed and screening for Vit. D deficiency in individuals at risk for deficiency is required, followed by the appropriate action.

  7. Software Code Maintainability : A Literature Review

    Directory of Open Access Journals (Sweden)

    Berna Seref

    2016-05-01

    Full Text Available Software Maintainability is one of the most important quality attributes. To increase quality of a software, to manage software more efficient and to decrease cost of the software, maintainability, maintainability estimation and maintainability evaluation models have been proposed. However, the practical use of these models in software engineering tools and practice remained little due to their limitations or threats to validity. In this paper, results of our Literature Review about maintainability models, maintainability metrics and maintainability estimation are presented. Aim of this paper is providing a baseline for further searches and serving the needs of developers and customers.

  8. Optimizing Bone Health in Duchenne Muscular Dystrophy

    Directory of Open Access Journals (Sweden)

    Jason L. Buckner

    2015-01-01

    Full Text Available Duchenne muscular dystrophy (DMD is an X-linked recessive disorder characterized by progressive muscle weakness, with eventual loss of ambulation and premature death. The approved therapy with corticosteroids improves muscle strength, prolongs ambulation, and maintains pulmonary function. However, the osteoporotic impact of chronic corticosteroid use further impairs the underlying reduced bone mass seen in DMD, leading to increased fragility fractures of long bones and vertebrae. These serious sequelae adversely affect quality of life and can impact survival. The current clinical issues relating to bone health and bone health screening methods in DMD are presented in this review. Diagnostic studies, including biochemical markers of bone turnover and bone mineral density by dual energy X-ray absorptiometry (DXA, as well as spinal imaging using densitometric lateral spinal imaging, and treatment to optimize bone health in patients with DMD are discussed. Treatment with bisphosphonates offers a method to increase bone mass in these children; oral and intravenous bisphosphonates have been used successfully although treatment is typically reserved for children with fractures and/or bone pain with low bone mass by DXA.

  9. Guided bone regeneration using individualized ceramic sheets.

    Science.gov (United States)

    Malmström, J; Anderud, J; Abrahamsson, P; Wälivaara, D-Å; Isaksson, S G; Adolfsson, E

    2016-10-01

    Guided bone regeneration (GBR) describes the use of membranes to regenerate bony defects. A membrane for GBR needs to be biocompatible, cell-occlusive, non-toxic, and mouldable, and possess space-maintaining properties including stability. The purpose of this pilot study was to describe a new method of GBR using individualized ceramic sheets to perfect bone regeneration prior to implant placement; bone regeneration was assessed using traditional histology and three-dimensional (3D) volumetric changes in the bone and soft tissue. Three patients were included. After full-thickness flap reflection, the individualized ceramic sheets were fixed. The sites were left to heal for 7 months. All patients were evaluated preoperatively and at 7 months postoperative using cone beam computed tomography and 3D optical equipment. Samples of the regenerated bone and soft tissue were collected and analyzed. The bone regenerated in the entire interior volume of all sheets. Bone biopsies revealed newly formed trabecular bone with a lamellar structure. Soft tissue biopsies showed connective tissue with no signs of an inflammatory response. This was considered to be newly formed periosteum. Thus ceramic individualized sheets can be used to regenerate large volumes of bone in both vertical and horizontal directions independent of the bone defect and with good biological acceptance of the material.

  10. 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...

  11. Maintaining quality in blood banking.

    Science.gov (United States)

    Harvey, E; Hewison, C; Nevalainen, D E; Lloyd, H L

    1995-03-01

    component will warrant redress. The degree of fault attributed to the producer will in part depend on whether they have met the best available standards at all stages in the preparation of the product. If a Transfusion Service can show that it's operation has external accreditation, particularly to an internationally recognised standard such as ISO 9000 and they can show that staff have been properly trained, that equipment is properly supplied and maintained and that the facility is appropriate to the work being carried out, then the liability that exists when something goes wrong will be reduced.(ABSTRACT TRUNCATED AT 400 WORDS)

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

    Science.gov (United States)

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

    2017-03-30

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

  13. Bone loss during simulated weightlessness - Is it glucocorticoid mediated?

    Science.gov (United States)

    Bikle, D. D.; Halloran, B. P.; Cone, C. M.; Morey-Holton, E.

    1985-01-01

    Elevating the hindquarters of a rat by the tail unweights the hind limbs but maintains normal weight-bearing by the forelimbs. This maneuver leads to a decrease in bone mass and calcium content in the unweighted bones (e.g., tibia and L1 vertebra), but not in the normally weighted bones (e.g., humerus and mandible). Potentially, the stress of the maneuver, mediated by increased glucocorticoid production and secretion, could explain the decreased bone formation, rather than the skeletal unweighting per se. To test this possibility, the effects of adrenalectomy on the response of bone to the unweighting of the hind limbs of normal rats were evaluated.

  14. 骨生化指标在骨肿瘤中的临床应用进展%Clinical application progress of bone biochemical markers in bone tumors

    Institute of Scientific and Technical Information of China (English)

    周定; 张琪琪; 胡勇

    2014-01-01

    Bone tumors refer to benign and malignant tumors which originate from mesenchymal stem cells and occur in bone tissues and their accessory structures. The pathogenesis and etiology of bone tumors still remain unclear, and the diagnosis methods of bone tumors are stagnating now. X-ray, computed tomography ( CT ) and magnetic resonance imaging ( MRI ) are important in diagnosing and evaluating bone tumors, but they cannot detect the lesions until the bone destruction reaches a certain degree. Isotope bone scan can detect the microscopic lesions of bone, whereas it is too expensive and the speciifcity is poor, with high false positive rates. At present, the golden standard for the diagnosis of bone tumors is the histopathological examination of bone. However, it is dififcult to achieve early diagnosis, and it is likely to miss the best treatment period. Every disease is inevitably accompanied by molecular biological changes in the body. Biochemical markers can promptly detect the property changes of bone tumor cells, including unlimited proliferation, apoptosis, active neoangiogenesis, inifltrative growth, metastatic growth and so on. Therefore, it is of great signiifcance for the diagnosis of bone tumors to detect appropriate biochemical markers in the patients. The normal bone metabolism is maintained by the dynamic balance of bone resorption and bone formation. When bone tumors occur, the balance will be disturbed. The bone biochemical markers which relfect bone resorption and bone formation are sensitive indicators of early abnormal bone metabolism. Recently, a large number of studies have explored the significance of bone biochemical markers in patients with bone tumors. The functions of bone biochemical markers in patients with bone tumors mainly include making an early detection of microscopic tumor lesions to start early treatment ( diagnostic effects ), evaluating the effects ( therapeutic monitoring ), evaluating the prognosis and predicting the risk of

  15. The Effects of Obesity on Murine Cortical Bone

    Science.gov (United States)

    Martin, Sophi

    This dissertation details the effects of obesity on the mechanical properties and structure of cortical bone. Obesity is associated with greater bone mineral content that might be expected to protect against fracture, which has been observed in adults. Paradoxically however, the incidence of bone fractures has been found to increase in overweight and obese children and adolescents. Femora from adolescent and adult mice fed a high-fat diet are investigated for changes in shape, tissue structure, as well as tissue-level and whole-bone mechanical properties. Results indicate increased bone size, reduced size-independent mechanical properties, but maintained size-dependent mechanical properties. Other changes in cortical bone response to obesity are observed with advancing age. This study indicates that bone quantity and bone quality play important compensatory roles in determining fracture risk, and that fracture risk may not be lessened for adults as previously thought.

  16. The molecular clock mediates leptin-regulated bone formation.

    Science.gov (United States)

    Fu, Loning; Patel, Millan S; Bradley, Allan; Wagner, Erwin F; Karsenty, Gerard

    2005-09-01

    The hormone leptin is a regulator of bone remodeling, a homeostatic function maintaining bone mass constant. Mice lacking molecular-clock components (Per and Cry), or lacking Per genes in osteoblasts, display high bone mass, suggesting that bone remodeling may also be subject to circadian regulation. Moreover, Per-deficient mice experience a paradoxical increase in bone mass following leptin intracerebroventricular infusion. Thus, clock genes may mediate the leptin-dependent sympathetic regulation of bone formation. We show that expression of clock genes in osteoblasts is regulated by the sympathetic nervous system and leptin. Clock genes mediate the antiproliferative function of sympathetic signaling by inhibiting G1 cyclin expression. Partially antagonizing this inhibitory loop, leptin also upregulates AP-1 gene expression, which promotes cyclin D1 expression, osteoblast proliferation, and bone formation. Thus, leptin determines the extent of bone formation by modulating, via sympathetic signaling, osteoblast proliferation through two antagonistic pathways, one of which involves the molecular clock.

  17. Structure and function of bone marrow hemopoiesis: mechanisms of response to ionizing radiation exposure.

    Science.gov (United States)

    Fliedner, T M; Graessle, D; Paulsen, C; Reimers, K

    2002-08-01

    It is the purpose of this presentation to review the unique structure and function of bone marrow anchored hematopoiesis in their significance for its response mechanisms to an exposure to ionizing radiation. The ultimate objective of bone marrow hematopoiesis is to maintain in the peripheral blood a constant level of the different blood cell types (erythrocytes, granulocytes, platelets, lymphocytes, etc.). All of them have their particular turnover kinetics (such as granulocytes 120 x 10(9)/d, erythrocytes 200 x 10(9)/d or thrombocytes 150 x 10(9)/d), are semi-autonomous in their steady state regulatory mechanisms and dependent on a life-long supply of mature cells from a stem cell pool with unlimited replicative and pluripotent differentiative potential. The present knowledge of hematopoietic cellular renewal is the result of years of basic experimental and clinical studies using radionuclides in various metabolic forms including (59)Fe, (32)P (DF (32)P), (51)Cr, (131)I, (60)Co, (3)H ((3)HTdR) and (14)C ((14)CTdR). To understand the physiology but in particular the radiation-pathophysiology, it is essential to recognize in detail the infrastructure of the bone marrow as a distinct unit. Indispensable for a life-long cell production is the capsule of the marrow - the bone cortex -, the arterial supply of blood connected to the sinusoidal microvascular architecture with its sinusoids contorti and recti as well as the central (cell collecting) sinusoids. It is further of importance to recognize the significance of nerval regulation of blood flow, characterized by myelinated and unmyelinated nerve fibers. The type of unique lining cells of the sinusoids is the prerequisite for the cell traffic between the hemopoietic parenchyma and the blood. This in turn cannot be achieved without an alternative opening and closing of the sinusoidal segments which - in turn - requires a rigid long capsule to assure an - in toto - constant volume of each bone marrow unit. If a bone

  18. Dating of cremated bones

    NARCIS (Netherlands)

    Lanting, JN; Aerts-Bijma, AT; van der Plicht, J; Boaretto, E.; Carmi, I.

    2001-01-01

    When dating unburnt bone, bone collagen, the organic fraction of the bone, is used. Collagen does not survive the heat of the cremation pyre, so dating of cremated bone has been considered impossible. Structural carbonate in the mineral fraction of the bone, however, survives the cremation process.

  19. Serum markers of bone metabolism show bone loss in hibernating bears

    Science.gov (United States)

    Donahue, S.W.; Vaughan, M.R.; Demers, L.M.; Donahue, H.J.

    2003-01-01

    Disuse osteopenia was studied in hibernating black bears (Ursus americanus) using serum markers of bone metabolism. Blood samples were collected from male and female, wild black bears during winter denning and active summer periods. Radioimmunoassays were done to determine serum concentrations of cortisol, the carboxy-terminal cross-linked telopeptide, and the carboxy-terminal propeptide of Type I procollagen, which are markers of hone resorption and formation, respectively. The bone resorption marker was significantly higher during winter hibernation than it was in the active summer months, but the bone formation marker was unchanged, suggesting an imbalance in bone remodeling and a net bone loss during disuse. Serum cortisol was significantly correlated with the bone resorption marker, but not with the bone formation marker. The bone formation marker was four- to fivefold higher in an adolescent and a 17-year-old bear early in the remobilization period compared with the later summer months. These findings raise the possibility that hibernating black bears may minimize bone loss during disuse by maintaining osteoblastic function and have a more efficient compensatory mechanism for recovering immobilization-induced bone loss than that of humans or other animals.

  20. A supra-cellular model for coupling of bone resorption to formation during remodeling

    DEFF Research Database (Denmark)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L

    2014-01-01

    by the osteoclasts. However, the osteoclasts are separated from the mature bone forming osteoblasts in time and space. Therefore the target cell of these osteoclastic factors has remained unknown. Recent explorations of the physical microenvironment of osteoclasts revealed a cell layer lining the bone marrow......The bone matrix is maintained functional through the combined action of bone resorbing osteoclasts and bone forming osteoblasts, in so-called bone remodeling units. The coupling of these two activities is critical for securing bone replenishment and involves osteogenic factors released...

  1. Counselor Identity: Conformity or Distinction?

    Science.gov (United States)

    McLaughlin, Jerry E.; Boettcher, Kathryn

    2009-01-01

    The authors explore 3 debates in other disciplines similar to counseling's identity debate in order to learn about common themes and outcomes. Conformity, distinction, and cohesion emerged as common themes. They conclude that counselors should retain their distinctive, humanistic approach rather than conforming to the dominant, medical approach.

  2. Is Face Distinctiveness Gender Based?

    Science.gov (United States)

    Baudouin, Jean-Yves; Gallay, Mathieu

    2006-01-01

    Two experiments were carried out to study the role of gender category in evaluations of face distinctiveness. In Experiment 1, participants had to evaluate the distinctiveness and the femininity-masculinity of real or artificial composite faces. The composite faces were created by blending either faces of the same gender (sexed composite faces,…

  3. Optimal Distinctiveness Signals Membership Trust.

    Science.gov (United States)

    Leonardelli, Geoffrey J; Loyd, Denise Lewin

    2016-07-01

    According to optimal distinctiveness theory, sufficiently small minority groups are associated with greater membership trust, even among members otherwise unknown, because the groups are seen as optimally distinctive. This article elaborates on the prediction's motivational and cognitive processes and tests whether sufficiently small minorities (defined by relative size; for example, 20%) are associated with greater membership trust relative to mere minorities (45%), and whether such trust is a function of optimal distinctiveness. Two experiments, examining observers' perceptions of minority and majority groups and using minimal groups and (in Experiment 2) a trust game, revealed greater membership trust in minorities than majorities. In Experiment 2, participants also preferred joining minorities over more powerful majorities. Both effects occurred only when minorities were 20% rather than 45%. In both studies, perceptions of optimal distinctiveness mediated effects. Discussion focuses on the value of relative size and optimal distinctiveness, and when membership trust manifests.

  4. Smoking and Bone Health

    Science.gov (United States)

    ... supported by your browser. Home Bone Basics Lifestyle Smoking and Bone Health Publication available in: PDF (85 ... late to adopt new habits for healthy bones. Smoking and Osteoporosis Cigarette smoking was first identified as ...

  5. In vivo monitoring of bone architecture and remodeling after implant insertion: The different responses of cortical and trabecular bone.

    Science.gov (United States)

    Li, Zihui; Kuhn, Gisela; von Salis-Soglio, Marcella; Cooke, Stephen J; Schirmer, Michael; Müller, Ralph; Ruffoni, Davide

    2015-12-01

    The mechanical integrity of the bone-implant system is maintained by the process of bone remodeling. Specifically, the interplay between bone resorption and bone formation is of paramount importance to fully understand the net changes in bone structure occurring in the peri-implant bone, which are eventually responsible for the mechanical stability of the bone-implant system. Using time-lapsed in vivo micro-computed tomography combined with new composite material implants, we were able to characterize the spatio-temporal changes of bone architecture and bone remodeling following implantation in living mice. After insertion, implant stability was attained by a quick and substantial thickening of the cortical shell which counteracted the observed loss of trabecular bone, probably due to the disruption of the trabecular network. Within the trabecular compartment, the rate of bone formation close to the implant was transiently higher than far from the implant mainly due to an increased mineral apposition rate which indicated a higher osteoblastic activity. Conversely, in cortical bone, the higher rate of bone formation close to the implant compared to far away was mostly related to the recruitment of new osteoblasts as indicated by a prevailing mineralizing surface. The behavior of bone resorption also showed dissimilarities between trabecular and cortical bone. In the former, the rate of bone resorption was higher in the peri-implant region and remained elevated during the entire monitoring period. In the latter, bone resorption rate had a bigger value away from the implant and decreased with time. Our approach may help to tune the development of smart implants that can attain a better long-term stability by a local and targeted manipulation of the remodeling process within the cortical and the trabecular compartments and, particularly, in bone of poor health.

  6. Stem cells in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Jeong Min [Department of Preventive and Social Dentistry and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Mantalaris, Anathathios, E-mail: yshwang@khu.ac.k [Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom)

    2010-12-15

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  7. Space maintainer effects on intercanine arch width and length.

    Science.gov (United States)

    Dincer, M; Haydar, S; Unsal, B; Turk, T

    1996-01-01

    In order to investigate the effects of space maintainers in intercanine arch width and length, twenty cases, characterized with the early loss of mandibular primary molars were selected and divided into two groups. The treatment group used removable space maintainers, while the other ten cases served as the control group. The first dental casts of the treatment and control groups were obtained when the primary canines were in the mouth. After the eruption of permanent canines second dental casts were obtained in both groups. Six measurements were made on the dental casts of each patient. No parameter was found to be statistically significant in the treatment group. In the control group the increase in intercanine arch width and perimeter were found to be statistically significant. Also the increase at the buccal and lingual bone measurements were found to be statistically significant. These results showed that space maintainers might cease the increase in intercanine arch width and length during the transition period between the primary and permanent canines.

  8. Distinctiveness of Ugandapithecus from Proconsul

    Directory of Open Access Journals (Sweden)

    Gommery, D.

    2009-12-01

    Full Text Available The decision to create the genus Ugandapithecus by Senut et al., 2000 has been criticised, either directly and in detail by MacLatchy & Rossie (2005b who argued that it is a junior synonym of Proconsul, or indirectly without providing reasons, firstly by Harrison (2001 who wrote that he did not retain it as a genus distinct from Proconsul, and then by Suwa et al., (2007 who employed the name “Ugandapithecus” with inverted commas, implying some degree of doubt about its validity as a genus, but without providing details. More recently Harrison & Andrews (2009 have recognised the Meswa sample as a separate species but they argue that it should be maintained within Proconsul, despite the morphological differences that it has from other species of the genus. We here re-examine the question by comparing, on the one hand, the holotype maxilla of Proconsul africanus, the type species of the genus, with the upper dentition of Ugandapithecus major, and, on the other hand, the holotype mandible of Ugandapithecus major with the lower dentition and mandibles previously attributed to Proconsul africanus. We conclude that the differences between the known upper and lower dentitions of P. africanus and U. major are of such a degree that the two taxa warrant generic separation, and that the differences are not related to sexual dimorphism. Where Proconsul africanus differs from Ugandapithecus major, it approaches Proconsul nyanzae and Proconsul heseloni from Rusinga.Furthermore, the range of morphometric variation within the fossil samples previously attributed to Ugandapithecus major is so great that it far surpasses variation in any other hominoid, fossil or extant. Previously this great amount of variation was interpreted to mean that U. major was extremely dimorphic, with huge males and small females, but if this is true, then U. major would be unique among hominoids in having females in which the cheek teeth fall completely outside the range of

  9. Space maintainers in dentistry: past to present.

    Science.gov (United States)

    Setia, Vikas; Pandit, Inder Kumar; Srivastava, Nikhil; Gugnani, Neeraj; Sekhon, Harveen Kaur

    2013-10-01

    Early orthodontic interventions are often initiated in the developing dentition to promote favourable developmental changes. Interceptive orthodontic can eliminate or reduce the severity of a developing malocclusion, the complexity of orthodontic treatment, overall treatment time and cost. The safest way to prevent future malocclusions from tooth loss is to place a space maintainer that is effective and durable. An appropriate use of space maintainer is advocated to hold the space until the eruption of permanent teeth. This case report describes the various changing trends in use of space maintainers: conventional band and loop, prefabricated band with custom made loop and glass fibre reinforced composite resins as space maintainers.

  10. Serum 25-hydroxyvitamin D cutoffs for functional bone measures in postmenopausal osteoporosis.

    Science.gov (United States)

    Lee, D Y; Jee, J H; Cho, Y Y; Jang, J Y; Yu, T Y; Kim, T H; Hong, Y J; Hong, W-J; Jin, S-M; Hur, K Y; Kim, J H; Kim, S W; Chung, J H; Lee, M K; Min, Y-K

    2017-04-01

    This study sought to determine the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health in postmenopausal women with low bone mass. A serum 25(OH)D concentration of 20 ng/mL rather than 30 ng/mL was appropriate for bone health.

  11. The Multiple Roles of Microrna-223 in Regulating Bone Metabolism

    Directory of Open Access Journals (Sweden)

    Yong Xie

    2015-10-01

    Full Text Available Bone metabolism is a lifelong process for maintaining skeletal system homeostasis, which is regulated by bone-resorbing osteoclasts and bone-forming osteoblasts. Aberrant differentiation of osteoclasts and osteoblasts leads to imbalanced bone metabolism, resulting in ossification and osteolysis diseases. MicroRNAs (miRNAs are pivotal factors in regulating bone metabolism via post-transcriptional inhibition of target genes. Recent studies have revealed that miR-223 exerts multiple effects on bone metabolism, especially in the processes of osteoclast and osteoblasts differentiation. In this review, we highlight the roles of miR-223 during the processes of osteoclast and osteoblast differentiation, as well as the potential clinical applications of miR-223 in bone metabolism disorders.

  12. 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...... lambs were randomly assigned to two weight-matched groups at birth. During the first 14 days of life AKG was administered orally to the experimental group (n=12) at the dosage of 0.1 g/kg body weight per day, while the control group (n=11) received an equal dose of the vehicle. Lambs were slaughtered...... has a long-term effect on skeletal development when given early in neonatal life, and that changes in rib properties serve to improve chest mechanics and functioning in young animals. Moreover, neonatal administration of AKG may be considered as an effective factor enhancing proper development...

  13. Distinction

    OpenAIRE

    2010-01-01

    Pr Serge Haroche La Médaille d’or 2009 du CNRS est décernée au Pr Serge Haroche, titulaire de la chaire de Physique quantique depuis 2001. Serge Haroche est spécialiste de physique atomique et d’optique quantique. Il est l’un des fondateurs de l’électrodynamique quantique en cavité, domaine qui permet, par des expériences conceptuellement simples, d’éclairer les fondements de la théorie quantique et de réaliser des prototypes de systèmes de traitement quantique de l’information. Serge Haroche...

  14. Load Bearing Equipment for Bone and Muscle

    Science.gov (United States)

    Shackelford, Linda; Griffith, Bryan

    2015-01-01

    Resistance exercise on ISS has proven effective in maintaining bone mineral density and muscle mass. Exploration missions require exercise with similar high loads using equipment with less mass and volume and greater safety and reliability than resistance exercise equipment used on ISS (iRED, ARED, FWED). Load Bearing Equipment (LBE) uses each exercising person to create and control the load to the partner.

  15. Towards improved scaffolds for bone tissue engineering

    NARCIS (Netherlands)

    Nandakumar, A.

    2012-01-01

    Tissue engineering aims to restore, maintain or improve tissue function of damaged tissues. In a classical set-up, a scaffold functions as a supporting structure and a carrier for growth factors and/or cells. Human mesenchymal stromal cells (hMSCs) have the ability to differentiate into bone, cartil

  16. 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

  17. Orchestration of bone remodeling

    NARCIS (Netherlands)

    Moester, Martiene Johanna Catharina

    2014-01-01

    In healthy individuals, a balance exists between bone formation and resorption. Disruption of this balance can lead to higher or lower bone mass, and disease such as osteoporosis. Treatment for osteoporosis generally inhibits bone resorption, but does not rebuild bone to a healthy strength. More kno

  18. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

    Full Text Available Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation.

  19. Bone Marrow Diseases

    Science.gov (United States)

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains stem cells. The stem cells can ... the platelets that help with blood clotting. With bone marrow disease, there are problems with the stem ...

  20. BONE IN OSTEOPETROSIS

    Directory of Open Access Journals (Sweden)

    Ramkumar

    2014-04-01

    Full Text Available Osteopetrosis, a generalized developmental bone disease due to genetic disturbances, characterized by failure of bone re sorption and continuous bone formation making the bone hard, dense and brittle. Bones of intramembranous ossification and enchondrial ossification are affected genetically and symmetrically. During the process of disease the excess bone formation obliterates the cranial foramina and presses the optic, auditory and facial nerves resulting in defective vision, impaired hearing and facial paralysis. The bone formation in osteopetrosis affects bone marrow function leading to severe anemia and deficient of blood cells. The bone devoid of blood supply due to compression of blood vessels by excess formation of bone are prone to osteomyelitic changes with suppuration and pathological fracture if exposed to infection. Though the condition is chronic progressive, it produces changes leading to fatal condition, it should be studied thoroughly by everyone and hence this article presents a classical case of osteopetrosis with detailed description and discussion for the benefit of readers

  1. Exonuclease 1 is essential for maintaining genomic stability and the proliferative capacity of neural but not hematopoietic stem cells

    Directory of Open Access Journals (Sweden)

    Junling Zhang

    2014-01-01

    Full Text Available Exonuclease 1 (Exo1 has been implicated in the regulation of DNA damage responses in stem cells with dysfunctional telomeres. However, it is unclear whether Exo1-mediated DNA maintenance pathways play a role in the maintenance of genomic stability and the self-renewal of tissue stem cells in mice with functional telomeres. Here, we analyzed the proliferative capacity of neural stem cells (NSCs and hematopoietic stem cells (HSCs from Exo1−/− mice. Our study shows that Exo1 deficiency impairs the maintenance of genomic stability and proliferative capacity in NSCs but not HSCs. In line with these results, we detected a decrease in proliferation and an up-regulation of p21 expression levels in Exo1-deficient NSCs but not Exo1-deficient HSCs. Our data provide experimental evidence that Exo1 deficiency has a differential impact on the homeostasis and proliferative capacity of tissue stem cells in the brain and bone marrow, suggesting that different tissue stem cells utilize distinct mechanisms for maintaining their genomic stability. Our current study provides important insight into the role of Exo1-mediated DNA maintenance pathways in the maintenance of genomic stability and the proliferative capacity of tissue stem cells.

  2. Multiscale Modeling of Bone

    Science.gov (United States)

    2014-12-01

    DISEASE Both age and disease can affect the structure of bone, the effects of which are often similar. The most common bone disease is osteoporosis ... Osteoporosis is a disease that results in reduced bone mass and density. This reduction of bone mass and density has a greater impact on trabecular...Bone loss in females is linked to a decrease in estrogen ; the decrease of estrogen associated with menopause increases osteoclast activity [89]. This

  3. Bone Health in Patients with Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Vit Zikan

    2011-01-01

    Full Text Available Multiple sclerosis (MS is a gait disorder characterized by acute episodes of neurological defects leading to progressive disability. Patients with MS have multiple risk factors for osteoporotic fractures, such as progressive immobilization, long-term glucocorticoids (GCs treatment or vitamin D deficiency. The duration of motor disability appears to be a major contributor to the reduction of bone strength. The long term immobilization causes a marked imbalance between bone formation and resorption with depressed bone formation and a marked disruption of mechanosensory network of tightly connected osteocytes due to increase of osteocyte apoptosis. Patients with higher level of disability have also higher risk of falls that combined with a bone loss increases the frequency of bone fractures. There are currently no recommendations how to best prevent and treat osteoporosis in patients with MS. However, devastating effect of immobilization on the skeleton in patients with MS underscores the importance of adequate mechanical stimuli for maintaining the bone structure and its mechanical competence. The physical as well as pharmacological interventions which can counteract the bone remodeling imbalance, particularly osteocyte apoptosis, will be promising for prevention and treatment of osteoporosis in patients with MS.

  4. Bone cysts: unicameral and aneurysmal bone cyst.

    Science.gov (United States)

    Mascard, E; Gomez-Brouchet, A; Lambot, K

    2015-02-01

    Simple and aneurysmal bone cysts are benign lytic bone lesions, usually encountered in children and adolescents. Simple bone cyst is a cystic, fluid-filled lesion, which may be unicameral (UBC) or partially separated. UBC can involve all bones, but usually the long bone metaphysis and otherwise primarily the proximal humerus and proximal femur. The classic aneurysmal bone cyst (ABC) is an expansive and hemorrhagic tumor, usually showing characteristic translocation. About 30% of ABCs are secondary, without translocation; they occur in reaction to another, usually benign, bone lesion. ABCs are metaphyseal, excentric, bulging, fluid-filled and multicameral, and may develop in all bones of the skeleton. On MRI, the fluid level is evocative. It is mandatory to distinguish ABC from UBC, as prognosis and treatment are different. UBCs resolve spontaneously between adolescence and adulthood; the main concern is the risk of pathologic fracture. Treatment in non-threatening forms consists in intracystic injection of methylprednisolone. When there is a risk of fracture, especially of the femoral neck, surgery with curettage, filling with bone substitute or graft and osteosynthesis may be required. ABCs are potentially more aggressive, with a risk of bone destruction. Diagnosis must systematically be confirmed by biopsy, identifying soft-tissue parts, as telangiectatic sarcoma can mimic ABC. Intra-lesional sclerotherapy with alcohol is an effective treatment. In spinal ABC and in aggressive lesions with a risk of fracture, surgical treatment should be preferred, possibly after preoperative embolization. The risk of malignant transformation is very low, except in case of radiation therapy.

  5. Investigations into Changes in Bone Turnover with Acute, Weight-Bearing Exercise in Healthy, Young Men

    Science.gov (United States)

    2009-10-01

    after the menopause . Subsequently, in the newly increased number of resorption spaces, bone formation occurs that is reflected by an increase in...specific BTM, new insights into the acute effects of exercise on bone resorption and formation are possible. 1.4 Nutrition , energy availability and...normal bone metabolism While the importance of appropriate nutrition in maintaining normal bone turnover has long been recognised, it is only with the

  6. Defining poverty as distinctively human

    Directory of Open Access Journals (Sweden)

    H.P.P. Lötter

    2007-05-01

    Full Text Available While it is relatively easy for most people to identify human beings suffering from poverty, it is rather more difficult to come to a proper understanding of poverty. In this article the author wants to deepen our understanding of poverty by interpreting the conventional definitions of poverty in a new light. The article starts with a defence of a claim that poverty is a concept uniquely applicable to humans. It then present a critical discussion of the distinction between absolute and relative poverty and it is then argued that a revision of this distinction can provide general standards applicable to humans everywhere.

  7. Coastal Maintained Channels in US waters

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This layer shows coastal channels and waterways that are maintained and surveyed by the U.S. Army Corps of Engineers (USACE). These channels are necessary...

  8. Sources and Information: Maintaining Institutional Integrity.

    Science.gov (United States)

    Palmer, Jim; Zwemer, Diane

    1985-01-01

    Provides an annotated bibliography of ERIC materials dealing with the community college mission, educational quality, maintaining an effective faculty, effects and management of retrenchment, and the state role in community college education. (LAL)

  9. Space Maintainers in Dentistry: Past to Present

    OpenAIRE

    Setia, Vikas; Pandit, Inder Kumar; Srivastava, Nikhil; Gugnani, Neeraj; Sekhon, Harveen Kaur

    2013-01-01

    Early orthodontic interventions are often initiated in the developing dentition to promote favourable developmental changes. Interceptive orthodontic can eliminate or reduce the severity of a developing malocclusion, the complexity of orthodontic treatment, overall treatment time and cost. The safest way to prevent future malocclusions from tooth loss is to place a space maintainer that is effective and durable. An appropriate use of space maintainer is advocated to hold the space until the e...

  10. Bone repair: Effects of physical exercise and LPS systemic exposition.

    Science.gov (United States)

    Nogueira, Jonatas E; Branco, Luiz G S; Issa, João Paulo M

    2016-08-01

    Bone repair can be facilitated by grafting, biochemical and physical stimulation. Conversely, it may be delayed lipopolysaccharide (LPS). Physical exercise exerts beneficial effects on the bone, but its effect on bone repair is not known. We investigated the effect of exercise on the LPS action on bone healing through bone densitometry, quantitative histological analysis for bone formation rate and immunohistochemical markers in sedentary and exercised animals. Rats ran on the treadmill for four weeks. After training the rats were submitted to a surgical procedure (bone defect in the right tibia) and 24h after the surgery LPS was administered at a dose of 100μg/kg i.p., whereas the control rats received a saline injection (1ml/kg, i.p.). Right tibias were obtained for analysis after 10days during which rats were not submitted to physical training. Physical exercise had a positive effect on bone repair, increasing bone mineral density, bone mineral content, bone formation rate, type I collagen and osteocalcin expression. These parameters were not affected by systemic administration of LPS. Our data indicate that physical exercise has an important osteogenic effect, which is maintained during acute systemic inflammation induced by exposure to a single dose of LPS.

  11. Computed tomography analysis of guinea pig bone: architecture, bone thickness and dimensions throughout development

    Directory of Open Access Journals (Sweden)

    Agata Witkowska

    2014-10-01

    Full Text Available The domestic guinea pig, Cavia aperea f. porcellus, belongs to the Caviidae family of rodents. It is an important species as a pet, a source of food and in medical research. Adult weight is achieved at 8–12 months and life expectancy is ∼5–6 years. Our aim was to map bone local thickness, structure and dimensions across developmental stages in the normal animal. Guinea pigs (n = 23 that had died of natural causes were collected and the bones manually extracted and cleaned. Institutional ethical permission was given under the UK Home Office guidelines and the Veterinary Surgeons Act. X-ray Micro Computed Tomography (microCT was undertaken on the left and right scapula, humerus and femur from each animal to ascertain bone local thickness. Images were also used to undertake manual and automated bone measurements, volumes and surface areas, identify and describe nutrient, supratrochlear and supracondylar foramina. Statistical analysis between groups was carried out using ANOVA with post-hoc testing. Our data mapped a number of dimensions, and mean and maximum bone thickness of the scapula, humerus and femur in guinea pigs aged 0–1 month, 1–3 months, 3–6 months, 6 months–1 year and 1–4 years. Bone dimensions, growth rates and local bone thicknesses differed between ages and between the scapula, humerus and femur. The microCT and imaging software technology showed very distinct differences between the relative local bone thickness across the structure of the bones. Only one bone showed a singular nutrient foramen, every other bone had between 2 and 5, and every nutrient canal ran in an oblique direction. In contrast to other species, a supratrochlear foramen was observed in every humerus whereas the supracondylar foramen was always absent. Our data showed the bone local thickness, bone structure and measurements of guinea pig bones from birth to 4 years old. Importantly it showed that bone development continued after 1 year, the point

  12. Computed tomography analysis of guinea pig bone: architecture, bone thickness and dimensions throughout development.

    Science.gov (United States)

    Witkowska, Agata; Alibhai, Aziza; Hughes, Chloe; Price, Jennifer; Klisch, Karl; Sturrock, Craig J; Rutland, Catrin S

    2014-01-01

    The domestic guinea pig, Cavia aperea f. porcellus, belongs to the Caviidae family of rodents. It is an important species as a pet, a source of food and in medical research. Adult weight is achieved at 8-12 months and life expectancy is ∼5-6 years. Our aim was to map bone local thickness, structure and dimensions across developmental stages in the normal animal. Guinea pigs (n = 23) that had died of natural causes were collected and the bones manually extracted and cleaned. Institutional ethical permission was given under the UK Home Office guidelines and the Veterinary Surgeons Act. X-ray Micro Computed Tomography (microCT) was undertaken on the left and right scapula, humerus and femur from each animal to ascertain bone local thickness. Images were also used to undertake manual and automated bone measurements, volumes and surface areas, identify and describe nutrient, supratrochlear and supracondylar foramina. Statistical analysis between groups was carried out using ANOVA with post-hoc testing. Our data mapped a number of dimensions, and mean and maximum bone thickness of the scapula, humerus and femur in guinea pigs aged 0-1 month, 1-3 months, 3-6 months, 6 months-1 year and 1-4 years. Bone dimensions, growth rates and local bone thicknesses differed between ages and between the scapula, humerus and femur. The microCT and imaging software technology showed very distinct differences between the relative local bone thickness across the structure of the bones. Only one bone showed a singular nutrient foramen, every other bone had between 2 and 5, and every nutrient canal ran in an oblique direction. In contrast to other species, a supratrochlear foramen was observed in every humerus whereas the supracondylar foramen was always absent. Our data showed the bone local thickness, bone structure and measurements of guinea pig bones from birth to 4 years old. Importantly it showed that bone development continued after 1 year, the point at which most guinea pigs have

  13. Monosodium glutamate-sensitive hypothalamic neurons contribute to the control of bone mass

    Science.gov (United States)

    Elefteriou, Florent; Takeda, Shu; Liu, Xiuyun; Armstrong, Dawna; Karsenty, Gerard

    2003-01-01

    Using chemical lesioning we previously identified hypothalamic neurons that are required for leptin antiosteogenic function. In the course of these studies we observed that destruction of neurons sensitive to monosodium glutamate (MSG) in arcuate nuclei did not affect bone mass. However MSG treatment leads to hypogonadism, a condition inducing bone loss. Therefore the normal bone mass of MSG-treated mice suggested that MSG-sensitive neurons may be implicated in the control of bone mass. To test this hypothesis we assessed bone resorption and bone formation parameters in MSG-treated mice. We show here that MSG-treated mice display the expected increase in bone resorption and that their normal bone mass is due to a concomitant increase in bone formation. Correction of MSG-induced hypogonadism by physiological doses of estradiol corrected the abnormal bone resorptive activity in MSG-treated mice and uncovered their high bone mass phenotype. Because neuropeptide Y (NPY) is highly expressed in MSG-sensitive neurons we tested whether NPY regulates bone formation. Surprisingly, NPY-deficient mice had a normal bone mass. This study reveals that distinct populations of hypothalamic neurons are involved in the control of bone mass and demonstrates that MSG-sensitive neurons control bone formation in a leptin-independent manner. It also indicates that NPY deficiency does not affect bone mass.

  14. Cthrc1 is a positive regulator of osteoblastic bone formation.

    Directory of Open Access Journals (Sweden)

    Hiroaki Kimura

    Full Text Available BACKGROUND: Bone mass is maintained by continuous remodeling through repeated cycles of bone resorption by osteoclasts and bone formation by osteoblasts. This remodeling process is regulated by many systemic and local factors. METHODOLOGY/PRINCIPAL FINDINGS: We identified collagen triple helix repeat containing-1 (Cthrc1 as a downstream target of bone morphogenetic protein-2 (BMP2 in osteochondroprogenitor-like cells by PCR-based suppression subtractive hybridization followed by differential hybridization, and found that Cthrc1 was expressed in bone tissues in vivo. To investigate the role of Cthrc1 in bone, we generated Cthrc1-null mice and transgenic mice which overexpress Cthrc1 in osteoblasts (Cthrc1 transgenic mice. Microcomputed tomography (micro-CT and bone histomorphometry analyses showed that Cthrc1-null mice displayed low bone mass as a result of decreased osteoblastic bone formation, whereas Cthrc1 transgenic mice displayed high bone mass by increase in osteoblastic bone formation. Osteoblast number was decreased in Cthrc1-null mice, and increased in Cthrc1 transgenic mice, respectively, while osteoclast number had no change in both mutant mice. In vitro, colony-forming unit (CFU assays in bone marrow cells harvested from Cthrc1-null mice or Cthrc1 transgenic mice revealed that Cthrc1 stimulated differentiation and mineralization of osteoprogenitor cells. Expression levels of osteoblast specific genes, ALP, Col1a1, and Osteocalcin, in primary osteoblasts were decreased in Cthrc1-null mice and increased in Cthrc1 transgenic mice, respectively. Furthermore, BrdU incorporation assays showed that Cthrc1 accelerated osteoblast proliferation in vitro and in vivo. In addition, overexpression of Cthrc1 in the transgenic mice attenuated ovariectomy-induced bone loss. CONCLUSIONS/SIGNIFICANCE: Our results indicate that Cthrc1 increases bone mass as a positive regulator of osteoblastic bone formation and offers an anabolic approach for the

  15. Alveolar bone loss: mechanisms, potential therapeutic targets, and interventions.

    Science.gov (United States)

    Intini, G; Katsuragi, Y; Kirkwood, K L; Yang, S

    2014-05-01

    This article reviews recent research into mechanisms underlying bone resorption and highlights avenues of investigation that may generate new therapies to combat alveolar bone loss in periodontitis. Several proteins, signaling pathways, stem cells, and dietary supplements are discussed as they relate to periodontal bone loss and regeneration. RGS12 is a crucial protein that mediates osteoclastogenesis and bone destruction, and a potential therapeutic target. RGS12 likely regulates osteoclast differentiation through regulating calcium influx to control the calcium oscillation-NFATc1 pathway. A working model for RGS10 and RGS12 in the regulation of Ca(2+) oscillations during osteoclast differentiation is proposed. Initiation of inflammation depends on host cell-microbe interactions, including the p38 mitogen-activated protein kinase (MAPK) signaling pathway. Oral p38 inhibitors reduced lipopolysaccharide (LPS)-induced bone destruction in a rat periodontitis model but showed unsatisfactory safety profiles. The p38 substrate MK2 is a more specific therapeutic target with potentially superior tolerability. Furthermore, MKP-1 shows anti-inflammatory activity, reducing inflammatory cytokine biosynthesis and bone resorption. Multipotent skeletal stem cell (SSC) populations exist within the bone marrow and periosteum of long bones. These bone-marrow-derived SSCs and periosteum-derived SSCs have shown therapeutic potential in several applications, including bone and periodontal regeneration. The existence of craniofacial bone-specific SSCs is suggested based on existing studies. The effects of calcium, vitamin D, and soy isoflavone supplementation on alveolar and skeletal bone loss in post-menopausal women were investigated. Supplementation resulted in stabilization of forearm bone mass density and a reduced rate of alveolar bone loss over 1 yr, compared with placebo. Periodontal attachment levels were also well-maintained and alveolar bone loss suppressed during 24 wk of

  16. Educational Psychology: The Distinctive Contribution

    Science.gov (United States)

    Cameron, R. J.

    2006-01-01

    This paper, written in the twenty-first anniversary year of the journal "Educational Psychology in Practice", attempts to uncover those distinctive aspects of the discipline and the practice of applied psychology in general and educational psychology in particular. After considering some of the reasons for attempting this task at this point in…

  17. Bioengineered periosteal progenitor cell sheets to enhance tendon-bone healing in a bone tunnel

    Directory of Open Access Journals (Sweden)

    Chih-Hsiang Chang

    2012-12-01

    Full Text Available Background: Tendon-bone tunnel healing is crucial for long term success in anterior cruciate liga­ment (ACL reconstruction. The periosteum contains osteochondral progenitor cells that can differenti­ate into osteoblasts and chondroblasts during tendon-bone healing. We developed a scaf­fold-free method using polymerized fibrin-coated dishes to make functional periosteal progenitor cell (PPC sheets. Bioengineered PPC sheets for enhancing tendon-bone healing were evaluated in an extra-articular bone tunnel model in rabbit. Methods: PPC derived from rabbit tibia periosteum, cultivated on polymerized fi­brin-coated dishes and harvested as PPC sheet. A confocal microscopy assay was used to evaluate the morphology of PPC sheets. PPC sheets as a periosteum to wrap around hamstring tendon grafts were pulled into a 3-mm diameter bone tunnel of tibia, and compared with a tendon graft without PPC sheets treatment. Rabbits were sacrificed at 4 and 8 weeks postoperatively for biochemical as­say and histological assay to demonstrate the enhancement of PPC sheets in tendon-bone healing. Results: PPC spread deposit on fibrin on the dish surface with continuous monolayer PPC was ob­served. Histological staining revealed that PPC sheets enhance collagen and glycosaminoglycans deposi­tion with fibrocartilage formation in the tendon-bone junction at 4 weeks. Collagen fiber with fibrocartilage formation at tendon-bone junction was also found at 8 weeks. Matured fibrocartilage and dense collagen fiber were formed at the tendon-bone interface at 8 weeks by Masson trichrome and Safranin-O staining Conclusions: Periosteal progenitor cell monolayer maintains the differentiated capacity and osteochon­dral potential in order to promote fibrocartilage formation in tendon-bone junction. Bioengi­neered PPC sheets can offer a new feasible therapeutic strategy of a novel approach to en­hance tendon-bone junction healing.

  18. A Roadmap to the Brittle Bones of Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    Ashwini P. Gore

    2011-01-01

    Full Text Available Cystic fibrosis (CF is an autosomal recessive disorder which despite advances in medical care continues to be a life-limiting and often fatal disease. With increase in life expectancy of the CF population, bone disease has emerged as a common complication. Unlike the osteoporosis seen in postmenopausal population, bone disease in CF begins at a young age and is associated with significant morbidity due to fractures, kyphosis, increased pain, and decreased lung function. The maintenance of bone health is essential for the CF population during their lives to prevent pain and fractures but also as they approach lung transplantation since severe bone disease can lead to exclusion from lung transplantation. Early recognition, prevention, and treatment are key to maintaining optimal bone health in CF patients and often require a multidisciplinary approach. This article will review the pathophysiology, current clinical practice guidelines, and potential future therapies for treating CF-related bone disease.

  19. Grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) prevent trabecular bone loss during disuse (hibernation).

    Science.gov (United States)

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Castillo, Alesha B; Kennedy, Oran; Condon, Keith W; Auger, Janene; Black, Hal L; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2009-12-01

    Disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. In contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). Trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. Here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (Ursus arctos horribilis) and black bear (Ursus americanus) trabecular bone in several skeletal locations. There were no differences in bone volume fraction or tissue mineral density between hibernating and active bears or between pre- and post-hibernation bears in the ilium, distal femur, or calcaneus. Though indices of cellular activity level (mineral apposition rate, osteoid thickness) decreased, trabecular bone resorption and formation indices remained balanced in hibernating grizzly bears. These data suggest that bears prevent bone loss during disuse by maintaining a balance between bone formation and bone resorption, which consequently preserves bone structure and strength. Further investigation of bone metabolism in hibernating bears may lead to the translation of mechanisms preventing disuse-induced bone loss in bears into novel treatments for osteoporosis.

  20. High bone turnover in Irish professional jockeys.

    LENUS (Irish Health Repository)

    Waldron-Lynch, F

    2012-02-01

    SUMMARY: Professional jockeys are routinely exposed to high impact trauma and sustain fractures frequently. We found that jockeys restrict their caloric intake in order to maintain regulation weights, and that bone turnover is high. There are significant health and safety implications for the racing industry. INTRODUCTION: Professional jockeys routinely sustain fractures from high impact falls. Jockeys maintain a low percentage body fat and a low body mass index (BMI) to achieve low weight targets in order to race. We evaluated dietary habits and bone metabolism in jockeys. METHODS: Bone mineral density (BMD) was measured in 27 male jockeys of the 144 jockeys licensed in Ireland. Fourteen (52%) had BMD T score below -1.0, of whom 12 consented to clinical review, nutritional survey, endocrine studies, and bone turnover markers (BTM). BTM were compared to age- and sex-matched controls (n = 16). RESULTS: BMI was 20.6 +\\/- 1.7 kg\\/m(2); previous fracture frequency was 3.2 +\\/- 2.0 per rider. All had normal endocrine axes. The jockeys\\' diet as determined by a 7-day dietary recall was deficient in energy, calcium, and vitamin D intake. Compared with the control group, the jockey group had evidence of increased bone turnover. CONCLUSIONS: A substantial proportion of the professional jockeys in Ireland have low-normal BMD, low BMI, and high bone turnover that may result from weight and dietary restrictions. These factors seem to have a deleterious effect on their bone health and predispose the jockeys to a high fracture risk that should be remediated.

  1. [原著]Prethymic Nylon Wool-Passed Bone Marrow Cells Can Make Distinction between Self and Non-Self X-Chromosome-Linked Gene Products (Xir Antigens) on the Stimulator Cells, Resulting in Regulation of the Generation of Cytotoxic T Lymphocytes in Mixed Lymphocyte Cultures

    OpenAIRE

    Higa, Moritake; Tanabe, MasaoJ; Department of Bacteriology, Faculty of, University of the Ryukyus, Okinawa, Japan; Research Institute of Comprehensive Medicine, School of Medicine, University of the Ryukyus, Okinawa, Japan

    1994-01-01

    We have previously reported that nylon wool-passed bone marrow cells treated with anti-Thy.1 antibody and complement (Thy.1 NW-BM cells) had helper-like activity which could augment the generation of cytotoxic T lymphocytes (CTL). In this study, we determined the antigens to which these NW-BM cells responded and recognized. When a few responder lymph node (LN) cells and an excess of NW-BM responder cells from BIOBR (H-2^k B10 background) mice were cultured with stimulator spleen cells from ei...

  2. Decreased bone turnover with balanced resorption and formation prevent cortical bone loss during disuse (hibernation) in grizzly bears (Ursus arctos horribilis).

    Science.gov (United States)

    McGee, Meghan E; Maki, Aaron J; Johnson, Steven E; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2008-02-01

    Disuse uncouples bone formation from resorption, leading to increased porosity, decreased bone geometrical properties, and decreased bone mineral content which compromises bone mechanical properties and increases fracture risk. However, black bear bone properties are not adversely affected by aging despite annual periods of disuse (i.e., hibernation), which suggests that bears either prevent bone loss during disuse or lose bone and subsequently recover it at a faster rate than other animals. Here we show decreased cortical bone turnover during hibernation with balanced formation and resorption in grizzly bear femurs. Hibernating grizzly bear femurs were less porous and more mineralized, and did not demonstrate any changes in cortical bone geometry or whole bone mechanical properties compared to active grizzly bear femurs. The activation frequency of intracortical remodeling was 75% lower during hibernation than during periods of physical activity, but the normalized mineral apposition rate was unchanged. These data indicate that bone turnover decreases during hibernation, but osteons continue to refill at normal rates. There were no changes in regional variation of porosity, geometry, or remodeling indices in femurs from hibernating bears, indicating that hibernation did not preferentially affect one region of the cortex. Thus, grizzly bears prevent bone loss during disuse by decreasing bone turnover and maintaining balanced formation and resorption, which preserves bone structure and strength. These results support the idea that bears possess a biological mechanism to prevent disuse osteoporosis.

  3. Grima: A Distinct Emotion Concept?

    Science.gov (United States)

    Schweiger Gallo, Inge; Fernández-Dols, José-Miguel; Gollwitzer, Peter M.; Keil, Andreas

    2017-01-01

    People experience an unpleasant sensation when hearing a scratch on a board or plate. The present research focuses on this aversive experience known in Spanish as ‘grima’ with no equivalent term in English and German. We hypothesized that this aversive experience constitutes a distinctive, separate emotional concept. In Study 1, we found that the affective meaning of ‘grima’ was closer to disgust than to other emotion concepts. Thus, in Study 2 we explored the features of grima and compared them with disgust. As grima was reported to be predominantly elicited by certain auditory stimuli and associated with a distinctive physiological pattern, Study 3 used direct measures of physiological arousal to test the assumption of a distinctive pattern of physiological responses elicited by auditory stimuli of grima and disgust, and found different effects on heart rate but not on skin conductance. In Study 4, we hypothesized that only participants with an implementation intention geared toward down-regulating grima would be able to successfully weaken the grima- but not disgust- experience. Importantly, this effect was specific as it held true for the grima-eliciting sounds only, but did not affect disgust-related sounds. Finally, Study 5 found that English and German speakers lack a single accessible linguistic label for the pattern of aversive reactions termed by Spanish speaking individuals as ‘grima’, whereas the elicitors of other emotions were accessible and accurately identified by German, English, as well as Spanish speakers. PMID:28217102

  4. What Is Bone Cancer?

    Science.gov (United States)

    ... start in bone, muscle, fibrous tissue, blood vessels, fat tissue, as well as some other tissues. They can develop anywhere in the body. There are several different types of bone tumors. Their names are based on ...

  5. Osteochondroma (Bone Tumor)

    Science.gov (United States)

    ... to be the most common benign bone tumor, accounting for 35% to 40% of all benign bone ... imaging scans. Doctors may also request computed tomography (CT) scans or magnetic resonance imaging (MRI) scans to ...

  6. What causes bone loss?

    Science.gov (United States)

    ... bone biology. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology . 13th ed. Philadelphia, PA: Elsevier; 2016:chap 29. Maes C, Kronenberg HM. Bone development and remodeling. In: Jameson JL, ...

  7. Bone mineral density test

    Science.gov (United States)

    BMD test; Bone density test; Bone densitometry; DEXA scan; DXA; Dual-energy x-ray absorptiometry; p-DEXA; Osteoporosis-BMD ... need to undress. This scan is the best test to predict your risk of fractures. Peripheral DEXA ( ...

  8. Collagen for bone tissue regeneration.

    Science.gov (United States)

    Ferreira, Ana Marina; Gentile, Piergiorgio; Chiono, Valeria; Ciardelli, Gianluca

    2012-09-01

    In the last decades, increased knowledge about the organization, structure and properties of collagen (particularly concerning interactions between cells and collagen-based materials) has inspired scientists and engineers to design innovative collagen-based biomaterials and to develop novel tissue-engineering products. The design of resorbable collagen-based medical implants requires understanding the tissue/organ anatomy and biological function as well as the role of collagen's physicochemical properties and structure in tissue/organ regeneration. Bone is a complex tissue that plays a critical role in diverse metabolic processes mediated by calcium delivery as well as in hematopoiesis whilst maintaining skeleton strength. A wide variety of collagen-based scaffolds have been proposed for different tissue engineering applications. These scaffolds are designed to promote a biological response, such as cell interaction, and to work as artificial biomimetic extracellular matrices that guide tissue regeneration. This paper critically reviews the current understanding of the complex hierarchical structure and properties of native collagen molecules, and describes the scientific challenge of manufacturing collagen-based materials with suitable properties and shapes for specific biomedical applications, with special emphasis on bone tissue engineering. The analysis of the state of the art in the field reveals the presence of innovative techniques for scaffold and material manufacturing that are currently opening the way to the preparation of biomimetic substrates that modulate cell interaction for improved substitution, restoration, retention or enhancement of bone tissue function.

  9. Gracile bone dysplasias

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, Kazimierz [Department of Medical Imaging, The Children' s Hospital at Westmead, Locked Bag 4001, Westmead 2145, NSW (Australia); Masel, John [Department of Radiology, Royal Children' s Hospital, Brisbane (Australia); Sillence, David O. [Department of Paediatrics and Child Health, The University of Sydney (Australia); Arbuckle, Susan [Department of Anatomical Pathology, The Children' s Hospital at Westmead, NSW (Australia); Juttnerova, Vera [Oddeleni Lekarske Genetiky, Hradec Kralove (Czech Republic)

    2002-09-01

    Gracile bone dysplasias constitute a group of disorders characterised by extremely slender bones with or without fractures. We report four newborns, two of whom showed multiple fractures. Two babies had osteocraniostenosis and one had features of oligohydramnios sequence. The diagnosis in the fourth newborn, which showed thin long bones and clavicles and extremely thin, poorly ossified ribs, is uncertain. Exact diagnosis of a gracile bone dysplasia is important for genetic counselling and medico-legal reasons. (orig.)

  10. Enzymatic maceration of bone

    DEFF Research Database (Denmark)

    Uhre, Marie-Louise; Eriksen, Anne Marie; Simonsen, Kim Pilkjær;

    2015-01-01

    the bones. The DNA analysis showed that DNA was preserved on all the pieces of bones which were examined. Finally, the investigation suggests that enzyme maceration could be gentler on the bones, as the edges appeared less frayed. The enzyme maceration was also a quicker method; it took three hours compared...

  11. Maintaining an Operational Flight Program (OFP)

    Science.gov (United States)

    1991-10-01

    Monitor And Control ( PMAC ), as an example, allows a maintainer to interact with his running OFP. Other specialized environment testing might indicate...paths on the F-15’s Central Computer. Processor Peculiar Tests Specialized testing for unique features of ECSs. Programmable Monitor And Control ( PMAC

  12. Maintaining Hope in the Face of Evil.

    Science.gov (United States)

    Miller, Geri

    2002-01-01

    P. G. Zimbardo (2001) and M. E. P. Seligman (in an interview with S. Carpenter, 2001) discuss evil and hope in response to the September 11, 2001, disaster. The implications for counseling are presented with an emphasis on how counselors can maintain hope for themselves and their clients in the face of evil. (Author)

  13. Maintaining strategic momentum : The CEO's agenda

    NARCIS (Netherlands)

    F.M. Maljers (Floris); C.W.F. Baden-Fuller (Charles); F.A.J. van den Bosch (Frans)

    1996-01-01

    textabstractThe question of how the CEO of a large complex organization maintain strategic momentum is addressed. This represents a great challenge when there are no obvious external threats, and no obvious reasons for having a concerted action. The inherent tensions which exist between stability an

  14. The randomized complexity of maintaining the minimum

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Chaudhuri, Shiva; Radhakrishnan, Jaikumar

    1996-01-01

    The complexity of maintaining a set under the operations Insert, Delete and FindMin is considered. In the comparison model it is shown that any randomized algorithm with expected amortized cost t comparisons per Insert and Delete has expected cost at least n/(e22t)-1 comparisons for FindMin. If F...

  15. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Arge, Lars; Mølhave, Thomas

    We consider maintaining the contour tree T of a piecewise-linear triangulation M that is the graph of a time varying height function h:R2→R. We carefully describe the combinatorial change in T that happen as h varies over time and how these changes relate to topological changes in M. We present...

  16. Treating Problem Behaviors Maintained by Negative Reinforcement.

    Science.gov (United States)

    Cipani, Ennio; Spooner, Fred

    1997-01-01

    Identifies four treatment techniques that may be applied when problem behavior is maintained by negative reinforcement: (1) functional communication training; (2) behavioral momentum; (3) differential reinforcement or an alternative escape behavior; and (4) errorless learning. Each of the techniques is defined, and applications and guidelines for…

  17. Maintaining ideal body weight counseling sessions

    Energy Technology Data Exchange (ETDEWEB)

    Brammer, S.H.

    1980-10-09

    The purpose of this program is to provide employees with the motivation, knowledge and skills necessary to maintain ideal body weight throughout life. The target audience for this program, which is conducted in an industrial setting, is the employee 40 years of age or younger who is at or near his/her ideal body weight.

  18. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Mølhave, Thomas; Revsbæk, Morten;

    2015-01-01

    We study the problem of maintaining the contour tree T of a terrain Sigma, represented as a triangulated xy-monotone surface, as the heights of its vertices vary continuously with time. We characterize the combinatorial changes in T and how they relate to topological changes in Sigma. We present ...

  19. How to Maintain a Social Reinforcement Program.

    Science.gov (United States)

    Arkin, Ronald; And Others

    This manual presents methodology for maintaining a social reinforcement system after supervisors in industrial environments have been trained in behavior modification theory and application. The maintenance manual discusses monitoring, evaluation, and integration of a company's employee performance system with the social reinforcement system…

  20. Oxytocin and bone

    Science.gov (United States)

    Sun, Li; Zaidi, Mone; Zallone, Alberta

    2014-01-01

    One of the most meaningful results recently achieved in bone research has been to reveal that the pituitary hormones have profound effect on bone, so that the pituitary-bone axis has become one of the major topics in skeletal physiology. Here, we discuss the relevant evidence about the posterior pituitary hormone oxytocin (OT), previously thought to exclusively regulate parturition and breastfeeding, which has recently been established to directly regulate bone mass. Both osteoblasts and osteoclasts express OT receptors (OTR), whose stimulation enhances bone mass. Consistent with this, mice deficient in OT or OTR display profoundly impaired bone formation. In contrast, bone resorption remains unaffected in OT deficiency because, even while OT stimulates the genesis of osteoclasts, it inhibits their resorptive function. Furthermore, in addition to its origin from the pituitary, OT is also produced by bone marrow osteoblasts acting as paracrine-autocrine regulator of bone formation modulated by estrogens. In turn, the power of estrogen to increase bone mass is OTR-dependent. Therefore, OTR−/− mice injected with 17β-estradiol do not show any effects on bone formation parameters, while the same treatment increases bone mass in wild-type mice. These findings together provide evidence for an anabolic action of OT in regulating bone mass and suggest that bone marrow OT may enhance the bone-forming action of estrogen through an autocrine circuit. This established new physiological role for OT in the maintenance of skeletal integrity further suggests the potential use of this hormone for the treatment of osteoporosis. PMID:25209411

  1. The Distinction Between English Synonyms

    Institute of Scientific and Technical Information of China (English)

    段佳

    2012-01-01

      A large number of new words and terms flock in the English vocabulary and English has a variety of expressive methods making it possible to express the same meaning by different words. Therefore English synonyms are so abundant that it is possible to describe the colorful world and to express the complicated, delicate human thought and emotions. But they bring people many problems such as the correct choice of words from synonyms. The reason for this problem is the insufficient knowledge of the distinction of English synonyms, which have differences in many aspects. This paper offers three main aspects in distinguishing English synonyms that include words’ meaning, coloring and usage.

  2. Bone regeneration with cultured human bone grafts

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, T.; Nakajima, H. [Nara Medical Univ., Kashihara City (Japan). Dept. of Pathology; Nara Medical Univ., Kashihara City (Japan). Dept. of Orthopedic Surgery; Ohgushi, H.; Ueda, Y.; Takakura, Y. [Nara Medical Univ., Kashihara City (Japan). Dept. of Orthopedic Surgery; Uemura, T.; Tateishi, T. [National Inst. for Advanced Interdisciplinary Research (NAIR), Ibaraki (Japan). Tsukuba Research Center; Enomoto, Y.; Ichijima, K. [Nara Medical Univ., Kashihara City (Japan). Dept. of Pathology

    2001-07-01

    From 73 year old female patient, 3 ml of bone marrow was collected from the ilium. The marrow was cultured to concentrate and expand the marrow mesenchymal cells on a culture dish. The cultured cells were then subculturedeither on another culture dish or in porous areas of hydroxyapatite ceramics in the presence of dexamethasone and beta-glycerophosphate (osteo genic medium). The subculturedtissues on the dishes were analyzed by scanning electron microscopy (SEM), and subculturedtissues in the ceramics were implanted intraperitoneally into athymic nude mice. Vigorous growth of spindle-shaped cells and a marked formation of bone matrix beneath the cell layers was observed on the subculture dishes by SEM. The intraperitoneally implanted ceramics with cultured tissues revealed thick layer of lamellar bone together with active osteoblasts lining in many pore areas of the ceramics after 8 weeks. The in vitro bone formations on the culture dishes and in vivo bone formation in porous ceramics were detected. These results indicate that we can assemble an in vitro bone/ceramic construct, and due to the porous framework of the ceramic, the construct has osteogenic potential similar to that of autologous cancellous bone. A significant benefit of this method is that the construct can be made with only a small amount of aspirated marrow cells from aged patients with little host morbidity. (orig.)

  3. A reappraisal of hemangiopericytoma of bone; analysis of cases reclassified as synovial sarcoma and solitary fibrous tumor of bone

    DEFF Research Database (Denmark)

    Verbeke, Sofie L J; Fletcher, Christopher D M; Alberghini, Marco;

    2010-01-01

    21 and 73 years. All tumors were located within bone, either sited within spine or extremities. All tumors showed thin-walled branching vessels surrounded by undifferentiated spindle or round cells. These cells showed variation in their morphologic pattern: 6 tumors showed a pattern-less architecture...... are characterized by distinct morphology and immunohistochemical profile. SFT of bone is located within spine and has a better prognosis, whereas SS of bone is located within long bones having a poor prognosis.......Hemangiopericytoma (HPC) was first described as a neoplasm with distinct morphologic features, presumably composed of pericytes. In soft tissue, it is accepted that most such lesions are solitary fibrous tumors (SFTs), monophasic synovial sarcomas (SSs), or myofibromatoses. It is unclear whether...

  4. The role of the perichondrium in fetal bone development.

    Science.gov (United States)

    Kronenberg, Henry M

    2007-11-01

    Most cells in mesenchymal condensations that form endochondral bone become chondrocytes; cells at the outer edges of the condensations, however, become perichondrial cells with distinct properties and functions. Some perichondrial cells become osteoblasts that populate both the future cortical and trabecular bone; others probably become chondrocytes. Perichondrial cells both send signals to the underlying growth cartilage and receive signals from the cartilage. Here I illustrate briefly examples of the complicated interactions between the perichondrium and the underlying growth cartilage.

  5. Divergent effects of obesity on bone health

    Science.gov (United States)

    Gower, Barbara A; Casazza, Krista

    2017-01-01

    Historically, obesity was thought to be advantageous for maintaining healthy bones due to the greater BMD observed in overweight individuals. However, recent observations of increased fracture in some obese individuals has led to concern that common metabolic complications of obesity, such as type 2 diabetes, metabolic syndrome, impaired glucose tolerance, insulin resistance, hyperglycemia, and inflammation may be associated with poor bone health. In support of this hypothesis, greater visceral fat, a hallmark of insulin resistance and metabolic syndrome, is associated with lower BMD. Research is needed to determine if and how visceral fat and/or poor metabolic health are causally associated with bone health. Clinicians should consider adding a marker metabolic health, such as waist circumference or fasting plasma glucose concentration, to other known risk factors for osteoporosis and fracture. PMID:24063845

  6. 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.

  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. [THE IMPORTANCE OF "MILK BONES" TO "WISDOM BONES" - COW MILK AND BONE HEALTH - LESSONS FROM MILK ALLERGY PATIENTS].

    Science.gov (United States)

    Nachshon, Liat; Katz, Yitzhak

    2016-03-01

    The necessity of milk consumption in the western diet is a subject of intense controversy. One of the main benefits of milk is that it is the main source of dietary calcium. Calcium is a major bone mineral, mandatory for bone health. Its supply is derived exclusively from external dietary sources. During the growth period, an increased calcium supply is needed for the process of bone mass accumulation. An optimal bone mass achieved by the end of the growth period may be protective later in life against the bone mass loss that commonly occurs. This in turn, can be preventative against the occurrence of osteoporosis and the development of spontaneous bone fractures. Over the past several decades, an increased incidence of osteoporosis has been documented in western countries, leading to high rates of morbidity and mortality in the middle-aged and geriatric population. Many studies have investigated the dietary calcium requirements for different ages, to achieve and maintain proper bone health. Based on their results, guidelines concerning calcium intake in every stage of life have been published by national and international organizations. In the western diet, it is difficult to achieve the recommended calcium intake without milk consumption. Moreover, calcium bioavailability for intestinal absorption is high. Several studies have recently raised doubts concerning the amounts of calcium intake in the western diet and its effectiveness in preventing osteoporosis. The main disadvantage of these studies is their being based on the patient's past memory recall of milk consumption. Patients with IgE-mediated cow's milk protein allergy are a unique population. Their lifetime negligible milk consumption is undisputed. A recent study investigated for the first time, the bone density of young adults with milk allergy at the end of their growth period. Their severe reduction in bone mineral density and dietary calcium intake defines them as a high risk group for the

  9. Operational handbook of the Bretby Maintainability Index

    Energy Technology Data Exchange (ETDEWEB)

    Rushworth, A.M.; Mason, S.; Talbot, C. (British Coal Corporation, Stanhope Bretby (United Kingdom). Technical Services and Research Executive, Ergonomics Branch)

    1994-01-01

    A substantial proportion of the injuries and costs in the mining industry, and in industry generally, occur during maintenance activities, particularly in work involving plant and machinery. A common thread linking the cause of these accidents and losses is a general deficiency in machine design, particularly the ergonomic aspects. This report concerns the Bretby Maintainability Index (BMI) which provides a comprehensive method of analysing and quantifying machinery maintainability in terms of health and safety and the financial implications associated with excessive downtime. The health and safety implications of poor machine design are discussed, as are the cost implications. The concept of the BMI is outlined and information on its application is given. Its detailed features are presented and guidance notes are provided.

  10. Diabetes, Biochemical Markers of Bone Turnover, Diabetes Control, and Bone

    OpenAIRE

    Starup-Linde, Jakob

    2013-01-01

    Diabetes mellitus is known to have late complications including micro vascular and macro vascular disease. This review focuses on another possible area of complication regarding diabetes; bone. Diabetes may affect bone via bone structure, bone density, and biochemical markers of bone turnover. The aim of the present review is to examine in vivo from humans on biochemical markers of bone turnover in diabetics compared to non-diabetics. Furthermore, the effect of glycemic control on bone marker...

  11. Maintaining Multimedia Data in a Geospatial Database

    Science.gov (United States)

    2012-09-01

    in a GIS are stored in two-dimensional space, which adds to the complexities faced in simulating a databases’ workload when the data is three...browsing, geocoding , reverse geocoding , flood risk, land information management, and toxic spill analysis. Jackpine was more in-depth than this thesis...benchmark testing. A. OVERVIEW In creating a GIS that maintains multimedia data, it is first important to note that the actual multimedia data is

  12. Maintainability Prediction and Analysis Study. Revision A

    Science.gov (United States)

    1978-07-01

    SS- 6b SECTION 1.0 INTRiODUCTION This document presents the results of a study to develop and document an improved maintainability prediction and...include operations on other RIs called out in the jth fault iscolation result . Tmujn Average time to perform the ruth corrective maintenance step for...of the study however, as the resulting time standards are used as Inputs In computing disassembly, interchange, and reassembly times for the

  13. Maintaining Wolbachia in Cell-free Medium

    OpenAIRE

    Gamston, Courtney; Rasgon, Jason

    2007-01-01

    In this video protocol, procedures are demonstrated to (1) purify Wolbachia symbionts out of cultured mosquito cells, (2) use a fluorescent assay to ascertain the viability of the purified Wolbachia and (3) maintain the now extracellular Wolbachia in cell-free medium. Purified Wolbachia remain alive in the extracellular phase but do not replicate until re-inoculated into eukaryotic cells. Extracellular Wolbachia purified in this manner will remain viable for at least a week at ...

  14. Aging and Bone Health in Individuals with Developmental Disabilities

    OpenAIRE

    Joan Jasien; Caitlin M Daimon; Stuart Maudsley; Shapiro, Bruce K.; Bronwen Martin

    2012-01-01

    Low bone mass density (BMD), a classical age-related health issue and a known health concern for fair skinned, thin, postmenopausal Caucasian women, is found to be common among individuals with developmental/intellectual disabilities (D/IDs). It is the consensus that BMD is decreased in both men and women with D/ID. Maintaining good bone health is important for this population as fractures could potentially go undetected in nonverbal individuals, leading to increased morbidity and a further l...

  15. Evaluation of soft tissue coverage over porous polymethylmethacrylate space maintainers within nonhealing alveolar bone defects.

    NARCIS (Netherlands)

    Kretlow, J.D.; Shi, M.; Young, S.; Spicer, P.P.; Demian, N.; Jansen, J.A.; Wong, M.E.; Kasper, F.K.; Mikos, A.G.

    2010-01-01

    Current treatment of traumatic craniofacial injuries often involves early free tissue transfer, even if the recipient site is contaminated or lacks soft tissue coverage. There are no current tissue engineering strategies to definitively regenerate tissues in such an environment at an early time poin

  16. "Lytic" lesions in autologous bone grafts: demonstration of medullary air pockets on post mortem computed tomography.

    Science.gov (United States)

    Rotman, A; Hamilton, K; O'Donnell, C

    2007-12-01

    Donor bone grafts are an important aspect of orthopaedic surgery. The use of plain film as a pathological screening tool before donor bone dispatch has revealed "lytic" lesions in proximal humeri. Donor demographics did not support the diagnosis of myeloma and subsequent computed tomography (CT) scans of these bones identified the lesions as air, not pathology. In total, 27 long bones were scanned and 100% (27/27 cases) exhibited air within the trabecular bone. Three distinct patterns were found: ovoid, linear/branching, and broad channel. A longitudinal course of CT scans was performed to identify at which stage air appeared within the bone. Pre-retrieval, preprocessing, and postprocessing scans revealed that air originated between the retrieval and preprocessing stages of donor bone preparation. There may be multiple aetiology of this phenomenon, including bone retrieval and natural decomposition.

  17. The Role of Hedgehog Signaling in Tumor Induced Bone Disease

    Directory of Open Access Journals (Sweden)

    Shellese A. Cannonier

    2015-08-01

    Full Text Available Despite significant progress in cancer treatments, tumor induced bone disease continues to cause significant morbidities. While tumors show distinct mutations and clinical characteristics, they behave similarly once they establish in bone. Tumors can metastasize to bone from distant sites (breast, prostate, lung, directly invade into bone (head and neck or originate from the bone (melanoma, chondrosarcoma where they cause pain, fractures, hypercalcemia, and ultimately, poor prognoses and outcomes. Tumors in bone secrete factors (interleukins and parathyroid hormone-related protein that induce RANKL expression from osteoblasts, causing an increase in osteoclast mediated bone resorption. While the mechanisms involved varies slightly between tumor types, many tumors display an increase in Hedgehog signaling components that lead to increased tumor growth, therapy failure, and metastasis. The work of multiple laboratories has detailed Hh signaling in several tumor types and revealed that tumor establishment in bone can be controlled by both canonical and non-canonical Hh signaling in a cell type specific manner. This review will explore the role of Hh signaling in the modulation of tumor induced bone disease, and will shed insight into possible therapeutic interventions for blocking Hh signaling in these tumors.

  18. The Role of Hedgehog Signaling in Tumor Induced Bone Disease

    Energy Technology Data Exchange (ETDEWEB)

    Cannonier, Shellese A.; Sterling, Julie A., E-mail: Julie.sterling@vanderbilt.edu [Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN 37235 (United States); Vanderbilt Center for Bone Biology, Department of Medicine, Division of Clinical Pharmacology Vanderbilt University, Nashville, TN 372335 (United States); Department of Cancer Biology, Vanderbilt University, Nashville, TN 37235 (United States)

    2015-08-26

    Despite significant progress in cancer treatments, tumor induced bone disease continues to cause significant morbidities. While tumors show distinct mutations and clinical characteristics, they behave similarly once they establish in bone. Tumors can metastasize to bone from distant sites (breast, prostate, lung), directly invade into bone (head and neck) or originate from the bone (melanoma, chondrosarcoma) where they cause pain, fractures, hypercalcemia, and ultimately, poor prognoses and outcomes. Tumors in bone secrete factors (interleukins and parathyroid hormone-related protein) that induce RANKL expression from osteoblasts, causing an increase in osteoclast mediated bone resorption. While the mechanisms involved varies slightly between tumor types, many tumors display an increase in Hedgehog signaling components that lead to increased tumor growth, therapy failure, and metastasis. The work of multiple laboratories has detailed Hh signaling in several tumor types and revealed that tumor establishment in bone can be controlled by both canonical and non-canonical Hh signaling in a cell type specific manner. This review will explore the role of Hh signaling in the modulation of tumor induced bone disease, and will shed insight into possible therapeutic interventions for blocking Hh signaling in these tumors.

  19. Bone and muscle atrophy with suspension of the rat

    Science.gov (United States)

    Leblanc, A.; Marsh, C.; Evans, H.; Johnson, P.; Schneider, V.; Jhingran, S.

    1985-01-01

    In order to identify a suitable model for the study of muscle atrophy due to suspension in space, a modified version of the Morey tail suspension model was used to measure the atrophic responses of rat bone and muscle to 14-30 days of unloading of the hindlimbs. The progress of atrophy was measured by increases in methylene diphosphonate (MDP) uptake. It is found that bone uptake of methylene diphosphonate followed a phasic pattern similar to changes in the bone formation rate of immobilized dogs and cats. Increased MDP uptake after a period of 60 days indicated an accelerated bone metabolism. Maximum muscle atrophy in the suspended rats was distinctly different from immobilization atrophy. On the basis of the experimental results, it is concluded that the tail suspension model is an adequate simulation of bone atrophy due to suspension.

  20. Primary Malignant Tumours of Bone Following Previous Malignancy

    Science.gov (United States)

    Patton, J. T.; Sommerville, S. M. M.; Grimer, R. J.

    2008-01-01

    Destructive bone lesions occurring in patients who have previously had a malignancy are generally assumed to be a metastasis from that malignancy. We reviewed 60 patients with a previous history of malignancy, who presented with a solitary bone lesion that was subsequently found to be a new and different primary sarcoma of bone. These second malignancies occurred in three distinct groups of patients: (1) patients with original tumours well known to be associated with second malignancies (5%); (2) patients whose second malignancies were likely to be due to the previous treatment of their primary malignancy (40%); (3) patients in whom there was no clearly defined association between malignancies (55%). The purpose of this study is to emphasise the necessity for caution in assuming the diagnosis of a metastasis when a solitary bone lesion is identified following a prior malignancy. Inappropriate biopsy and treatment of primary bone sarcomas compromises limb salvage surgery and can affect patient mortality. PMID:18414590

  1. Primary Malignant Tumours of Bone Following Previous Malignancy

    Directory of Open Access Journals (Sweden)

    R. J. Grimer

    2008-04-01

    Full Text Available Destructive bone lesions occurring in patients who have previously had a malignancy are generally assumed to be a metastasis from that malignancy. We reviewed 60 patients with a previous history of malignancy, who presented with a solitary bone lesion that was subsequently found to be a new and different primary sarcoma of bone. These second malignancies occurred in three distinct groups of patients: (1 patients with original tumours well known to be associated with second malignancies (5%; (2 patients whose second malignancies were likely to be due to the previous treatment of their primary malignancy (40%; (3 patients in whom there was no clearly defined association between malignancies (55%. The purpose of this study is to emphasise the necessity for caution in assuming the diagnosis of a metastasis when a solitary bone lesion is identified following a prior malignancy. Inappropriate biopsy and treatment of primary bone sarcomas compromises limb salvage surgery and can affect patient mortality.

  2. Establishing and maintaining the Langerhans cell network.

    Science.gov (United States)

    Chopin, Michaël; Nutt, Stephen L

    2015-05-01

    Langerhans cells (LCs) are the unique antigen-presenting cell of the epidermis. LCs have long been depicted in textbooks as the archetypical dendritic cell that alerts the immune system upon pathogen induced skin barrier breakage, however recent findings argue instead for a more tolerogenic function. While the LCs that populate the epidermis in steady-state arise from progenitors that seed the skin during embryogenesis, it is now apparent that a second pathway generating LCs from a bone marrow derived progenitor is active in inflammatory settings. This review emphasizes the determinants underpinning the establishment of the LC network in steady-state and under inflammatory conditions, as well as the transcriptional machinery governing their differentiation. The dual origin of LCs raises important questions about the functional differences between these subsets in balancing the epidermal immune response between immunity and tolerance.

  3. Cytokine-Mediated Bone Destruction in Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Seung Min Jung

    2014-01-01

    Full Text Available Bone homeostasis, which involves formation and resorption, is an important process for maintaining adequate bone mass in humans. Rheumatoid arthritis (RA is an autoimmune disease characterized by inflammation and bone loss, leading to joint destruction and deformity, and is a representative disease of disrupted bone homeostasis. The bone loss and joint destruction are mediated by immunological insults by proinflammatory cytokines and various immune cells. The connection between bone and immunity has been intensely studied and comprises the emerging field of osteoimmunology. Osteoimmunology is an interdisciplinary science investigating the interplay between the skeletal and the immune systems. The main contributors in osteoimmunology are the bone effector cells, such as osteoclasts or osteoblasts, and the immune cells, particularly lymphocytes and monocytes. Physiologically, osteoclasts originate from immune cells, and immune cells regulate osteoblasts and vice versa. Pathological conditions such as RA might affect these interactions, thereby altering bone homeostasis, resulting in the unfavorable outcome of bone destruction. In this review, we describe the osteoclastogenic roles of the proinflammatory cytokines and immune cells that are important in the pathophysiology of RA.

  4. A Bone Glue with Sustained Adhesion under Wet Conditions.

    Science.gov (United States)

    Wistlich, Laura; Rücker, Anja; Schamel, Martha; Kübler, Alexander C; Gbureck, Uwe; Groll, Jürgen

    2017-02-01

    Bone glues often suffer from low adhesion to bone under wet conditions. This study aims to improve wet adhesiveness of a bone glue based on a photocurable poly(ethylene glycol) dimethacrylate matrix through in situ interpenetrating network formation by addition of six-armed isocyanate functional star-shaped prepolymers (NCO-sP(EO-stat-PO)). Biodegradable ceramic fillers are added to adjust the paste workability. The 3-point bending strength of the bone glues is in the range of 3.5-5.5 MPa and not significantly affected by the addition of NCO-sP(EO-stat-PO). Storage in phosphate buffered saline (PBS) decreases the bending strength of all formulations to approximately 1 MPa but the adhesion to cortical bone increases from 0.15-0.2 to 0.3-0.5 MPa after adding 20-40 wt% NCO-sP(EO-stat-PO) to the matrix. Bone glues without the NCO-sP(EO-stat-PO) additive lose their adhesiveness to bone after aging in PBS for 7 days, whereas modified glues maintain a shear strength of 0.18-0.25 MPa demonstrating the efficacy of the approach. Scanning electron microscopy and energy-dispersive X-ray spectroscopy investigations of the fracture surfaces prove a high amount of residual adhesive on the bone surface indicating that adhesion to the bone under wet conditions is stronger than cohesion.

  5. Octacalcium phosphate combined with collagen orthotopically enhances bone regeneration.

    Science.gov (United States)

    Kamakura, Shinji; Sasaki, Kazuo; Honda, Yoshitomo; Anada, Takahisa; Suzuki, Osamu

    2006-11-01

    Octacalcium phosphate (OCP) is resorbable bone regenerative material, but its brittleness makes it difficult to maintain its shape without restraint. We have engineered a scaffold constructed of synthetic OCP and porcine collagen sponge (OCP/Collagen) and investigated whether OCP/Collagen composite could improve bone regeneration. To examine this hypothesis, bone regeneration by the implantation of OCP/Collagen was compared with those by OCP and collagen. Radiographic and histological examination was performed and the percentage of newly formed bone (n-Bone%) in the defect was determined by a histomorphometrical analysis. OCP/Collagen, OCP, or collagen was implanted into the critical-sized defects in rat crania and fixed at 2, 4, or 8 weeks after implantation. OCP/Collagen improved the handling performance than the granules of OCP, and synergistically enhanced the bone regeneration beyond expectation, which were composed of bone nucleation by OCP and cell infiltration by collagen. Histomorphometrical analysis showed that n-Bone% +/- standard error treated with OCP/Collagen (48.4 +/- 5.14) was significantly higher than those with OCP (27.6 +/- 4.04) or collagen (27.4 +/- 5.69) in week 8. The present study suggests that the combination OCP with collagen elicited the synergistic effect for bone regeneration.

  6. Anti-Aging Effects of the Hanwoo Leg Bone, Foot and Tail Infusions (HLI, HFI and HTI) on Skin Fibroblast

    OpenAIRE

    Seol, Ja young; Yoon, Ji Young; Jeong, Hee Sun; Joo, Nami; Choi, Soon Young

    2016-01-01

    Many researchers revealed that collagen contribute to maintaining the skin’s elasticity and inhibit wrinkling of skin. Korean native cattle (Hanwoo) bone (leg bone, foot and tail) infusion contains the various inorganic materials, collagen and chondroitin sulfate. All of this, a large quantity of collagen is included in Hanwoo infusion. Therefore, this study emphasized on the effects of collagen in the Hanwoo bone infusion. For the first time, Hanwoo bone infusions were directly added to the ...

  7. Temporal bone fracture and its complications

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To explore the characteristics and treatment oftemporal bone fractures and injuries in the medial-inner ear.Methods: The clinical data of 48 cases of temporal bone fractures admitted to our hospital from January 1989 to November 1999 were retrospectively analyzed.Results: Forty-eight patients with temporal bone fractures accounted for 17.00% of the homochronous craniofacial fractures. Of the 48 cases, temporal bone fractures induced by traffic accidents accounted for 66.67%, capillary fractures for 93.75%, medial-inner ear injuries or craniocerebral injuries for 77.08% and hearing loss or tinnitus for 48.00%. The cerebrospinal fluid (CSF) otorrhea and facioplegia accounted for 36.70% and 3.00%, respectively, in the longitudinal fractures, while they were 25.00% and 37.50%, respectively, in the transversal fractures. Primary emergent operations were performed on 46 cases and neurosurgery accounted for 46.00%. Secondary procedures accounted for 16.70%. As a result, 43 cases survived (89.58%) and 5 died (10.41%).Conclusions: Traffic injury is the first high-dangerous factor for temporal bone fractures, which are often complicated with medial-inner ear or craniocerebral injury. The CSF otorrhea is common in the longitudinal fractures and facioplegia is common in the transversal fractures. The key step is to rescue the life, keep the airway unobstructed and maintain the circulation in the primary emergency treatment.

  8. Identifying crucial parameter correlations maintaining bursting activity.

    Directory of Open Access Journals (Sweden)

    Anca Doloc-Mihu

    2014-06-01

    Full Text Available Recent experimental and computational studies suggest that linearly correlated sets of parameters (intrinsic and synaptic properties of neurons allow central pattern-generating networks to produce and maintain their rhythmic activity regardless of changing internal and external conditions. To determine the role of correlated conductances in the robust maintenance of functional bursting activity, we used our existing database of half-center oscillator (HCO model instances of the leech heartbeat CPG. From the database, we identified functional activity groups of burster (isolated neuron and half-center oscillator model instances and realistic subgroups of each that showed burst characteristics (principally period and spike frequency similar to the animal. To find linear correlations among the conductance parameters maintaining functional leech bursting activity, we applied Principal Component Analysis (PCA to each of these four groups. PCA identified a set of three maximal conductances (leak current, [Formula: see text]Leak; a persistent K current, [Formula: see text]K2; and of a persistent Na+ current, [Formula: see text]P that correlate linearly for the two groups of burster instances but not for the HCO groups. Visualizations of HCO instances in a reduced space suggested that there might be non-linear relationships between these parameters for these instances. Experimental studies have shown that period is a key attribute influenced by modulatory inputs and temperature variations in heart interneurons. Thus, we explored the sensitivity of period to changes in maximal conductances of [Formula: see text]Leak, [Formula: see text]K2, and [Formula: see text]P, and we found that for our realistic bursters the effect of these parameters on period could not be assessed because when varied individually bursting activity was not maintained.

  9. Take Control of Maintaining Your Mac

    CERN Document Server

    Kissell, Joe

    2009-01-01

    Keep your Mac running smoothly with our easy maintenance program! Regular maintenance is necessary to avoid problems and to ensure your Mac runs at peak performance, but it's hard to know what to do and when to do it. Best-selling author Joe Kissell has now applied his commonsense approach to the task of maintaining your Mac, whether you use Tiger or Leopard! Learn how to start on the right foot; what you should do daily, weekly, monthly, and yearly; and how to prepare for Mac OS X updates. Joe even explains how to monitor your Mac's health and debunks common panaceas. Read this book to lea

  10. Maintenance of Bone Homeostasis by DLL1-Mediated Notch Signaling.

    Science.gov (United States)

    Muguruma, Yukari; Hozumi, Katsuto; Warita, Hiroyuki; Yahata, Takashi; Uno, Tomoko; Ito, Mamoru; Ando, Kiyoshi

    2016-10-13

    Adult bone mass is maintained through a balance of the activities of osteoblasts and osteoclasts. Although Notch signaling has been shown to maintain bone homeostasis by controlling the commitment, differentiation, and function of cells in both the osteoblast and osteoclast lineages, the precise mechanisms by which Notch performs such diverse and complex roles in bone physiology remain unclear. By using a transgenic approach that modified the expression of delta-like 1 (DLL1) or Jagged1 (JAG1) in an osteoblast-specific manner, we investigated the ligand-specific effects of Notch signaling in bone homeostasis. This study demonstrated for the first time that the proper regulation of DLL1 expression, but not JAG1 expression, in osteoblasts is essential for the maintenance of bone remodeling. DLL1-induced Notch signaling was responsible for the expansion of the bone-forming cell pool by promoting the proliferation of committed but immature osteoblasts. However, DLL1-Notch signaling inhibited further differentiation of the expanded osteoblasts to become fully matured functional osteoblasts, thereby substantially decreasing bone formation. Osteoblast-specific expression of DLL1 did not alter the intrinsic differentiation ability of cells of the osteoclast lineage. However, maturational arrest of osteoblasts caused by the DLL1 transgene impaired the maturation and function of osteoclasts due to a failed osteoblast-osteoclast coupling, resulting in severe suppression of bone metabolic turnover. Taken together, DLL1-mediated Notch signaling is critical for proper bone remodeling as it regulates the differentiation and function of both osteoblasts and osteoclasts. Our study elucidates the importance of ligand-specific activation of Notch signaling in the maintenance of bone homeostasis. This article is protected by copyright. All rights reserved.

  11. Bone building with bortezomib

    Science.gov (United States)

    Roodman, G. David

    2008-01-01

    In this issue of the JCI, Mukherjee et al. report that bortezomib, a clinically available proteasome inhibitor active against myeloma, induces the differentiation of mesenchymal stem/progenitor cells (MSCs) — rather than mature osteoprogenitor cells — into osteoblasts, resulting in new bone formation (see the related article beginning on page 491). These results were observed when MSCs were implanted subcutaneously in mice or were used to treat a mouse model of postmenopausal bone loss. Others have reported that immunomodulatory drugs (e.g., thalidomide and lenalidomide), which are active against myeloma, also block the activity of bone-resorbing osteoclasts. These results reflect the utility of targeting endogenous MSCs for the purpose of tissue repair and suggest that combining different classes of agents that are antineoplastic and also inhibit bone destruction and increase bone formation should be very beneficial for myeloma patients suffering from severe bone disease. PMID:18219395

  12. Osteogenesis and angiogenesis: The potential for engineering bone

    Directory of Open Access Journals (Sweden)

    JM Kanczler

    2008-05-01

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

  13. Adrenal gland and bone.

    Science.gov (United States)

    Hardy, Rowan; Cooper, Mark S

    2010-11-01

    The adrenal gland synthesizes steroid hormones from the adrenal cortex and catecholamines from the adrenal medulla. Both cortisol and adrenal androgens can have powerful effects on bone. The overproduction of cortisol in Cushing's disease leads to a dramatic reduction in bone density and an increase risk of fracture. Overproduction of adrenal androgens in congenital adrenal hyperplasia (CAH) leads to marked changes in bone growth and development with early growth acceleration but ultimately a significant reduction in final adult height. The role of more physiological levels of glucocorticoids and androgens on bone metabolism is less clear. Cortisol levels measured in elderly individuals show a weak correlation with measures of bone density and change in bone density over time with a high cortisol level associated with lower bone density and more rapid bone loss. Cortisol levels and the dynamics of cortisol secretion change with age which could also explain some age related changes in bone physiology. It is also now clear that adrenal steroids can be metabolized within bone tissue itself. Local synthesis of cortisol within bone from its inactive precursor cortisone has been demonstrated and the amount of cortisol produced within osteoblasts appears to increase with age. With regard to adrenal androgens there is a dramatic reduction in levels with aging and several studies have examined the impact that restoration of these levels back to those seen in younger individuals has on bone health. Most of these studies show small positive effects in women, not men, but the skeletal sites where benefits are seen varies from study to study.

  14. Bone scanning in otolaryngology.

    Science.gov (United States)

    Noyek, A M

    1979-09-01

    Modern radionuclide bone scanning has introduced a new concept in physiologic and anatomic diagnostic imaging to general medicine. As otolaryngologists must diagnose and treat disease in relation to the bony and/or cartilaginous supporting structures of the neurocranium and upper airway, this modality should be included in the otolaryngologist's diagnostic armamentarium. It is the purpose of this manuscript to study the specific applications of bone scanning to our specialty at this time, based on clinical experience over the past three years. This thesis describes the development of bone scanning in general (history of nuclear medicine and nuclear physics; history of bone scanning in particular). General concepts in nuclear medicine are then presented; these include a discussion of nuclear semantics, principles of radioactive emmissions, the properties 99mTc as a radionuclide, and the tracer principle. On the basis of these general concepts, specific concepts in bone scanning are then brought forth. The physiology of bone and the action of the bone scan agents is presented. Further discussion considers the availability and production of the bone scan agent, patient factors, the gamma camera, the triphasic bone scan and the ultimate diagnostic principle of the bone scan. Clinical applications of bone scanning in otolaryngology are then presented in three sections. Proven areas of application include the evaluation of malignant tumors of the head and neck, the diagnosis of temporomandibular joint disorders, the diagnosis of facial fractures, the evaluation of osteomyelitis, nuclear medicine imaging of the larynx, and the assessment of systemic disease. Areas of adjunctive or supplementary value are also noted, such as diagnostic imaging of meningioma. Finally, areas of marginal value in the application of bone scanning are described.

  15. Experience of maintaining laboratory educational website's sustainability

    Science.gov (United States)

    Dimenstein, Izak B.

    2016-01-01

    Laboratory methodology websites are specialized niche websites. The visibility of a niche website transforms it into an authority site on a particular “niche of knowledge.” This article presents some ways in which a laboratory methodology website can maintain its sustainability. The optimal composition of the website includes a basic content, a blog, and an ancillary part. This article discusses experimenting with the search engine optimization query results page. Strategic placement of keywords and even phrases, as well as fragmentation of the post's material, can improve the website's visibility to search engines. Hyperlinks open a chain reaction of additional links and draw attention to the previous posts. Publications in printed periodicals are a substantial part of a niche website presence on the Internet. Although this article explores a laboratory website on the basis of our hands-on expertise maintaining “Grossing Technology in Surgical Pathology” (www.grossing-technology.com) website with a high volume of traffic for more than a decade, the recommendations presented here for developing an authority website can be applied to other professional specialized websites. The authority websites visibility and sustainability are preconditions for aggregating them in a specialized educational laboratory portal. PMID:27688928

  16. Maintaining extensivity in evolutionary multiplex networks

    CERN Document Server

    Antonopoulos, Chris G

    2015-01-01

    In this Letter, we explore the role of network topology on its extensive character. We study analytically and numerically how the topology contributes to maintaining extensivity of entropy in multiplex networks, i.e. networks of subnetworks, by means of the sum of the positive Lyapunov exponents, $H_{KS}$, a quantity related to entropy. We show that extensivity relies not only on the interplay between the coupling strengths of the dynamics associated to the intra (short-range) and inter (long-range) interactions, but also on the sum of the intra-degrees of the nodes of the subnetworks. For the analytically treated networks of size $N$, if the sum of the intra-degrees (and the sum of inter-degrees) scales as $N^{\\theta+1}$, extensivity can be maintained if the intra-coupling (and the inter-coupling) strength scales as $N^{-\\theta}$, when evolution is driven by the maximization of $H_{KS}$. We then verify our analytical result by doing numerical simulations in multiplex networks formed by electrically and chemi...

  17. Maintaining heterokaryosis in pseudo-homothallic fungi.

    Science.gov (United States)

    Grognet, Pierre; Silar, Philippe

    2015-01-01

    Among all the strategies displayed by fungi to reproduce and propagate, some species have adopted a peculiar behavior called pseudo-homothallism. Pseudo-homothallic fungi are true heterothallics, i.e., they need 2 genetically-compatible partners to mate, but they produce self-fertile mycelium in which the 2 different nuclei carrying the compatible mating types are present. This lifestyle not only enables the fungus to reproduce without finding a compatible partner, but also to cross with any mate it may encounter. However, to be fully functional, pseudo-homothallism requires maintaining heterokaryosis at every stage of the life cycle. We recently showed that neither the structure of the mating-type locus nor hybrid-enhancing effect due to the presence of the 2 mating types accounts for the maintenance of heterokaryosis in the pseudo-homothallic fungus P. anserina. In this addendum, we summarize the mechanisms creating heterokaryosis in P. anserina and 2 other well-known pseudo-homothallic fungi, Neurospora tetrasperma and Agaricus bisporus. We also discuss mechanisms potentially involved in maintaining heterokaryosis in these 3 species.

  18. Hypercalciuric Bone Disease

    Science.gov (United States)

    Favus, Murray J.

    2008-09-01

    Hypercalciuria plays an important causal role in many patients with calcium oxalate (CaOx) stones. The source of the hypercalciuria includes increased intestinal Ca absorption and decreased renal tubule Ca reabsorption. In CaOx stone formers with idiopathic hypercalciuria (IH), Ca metabolic balance studies have revealed negative Ca balance and persistent hypercalciuria in the fasting state and during low dietary Ca intake. Bone resorption may also contribute to the high urine Ca excretion and increase the risk of bone loss. Indeed, low bone mass by DEXA scanning has been discovered in many IH patients. Thiazide diuretic agents reduce urine Ca excretion and may increase bone mineral density (BMD), thereby reducing fracture risk. Dietary Ca restriction that has been used unsuccessfully in the treatment of CaOx nephrolithiasis in the past may enhance negative Ca balance and accelerate bone loss. DEXA scans may demonstrate low BMD at the spine, hip, or forearm, with no predictable pattern. The unique pattern of bone histologic changes in IH differs from other causes of low DEXA bone density including postmenopausal osteoporosis, male hypogonadal osteoporosis, and glucocorticoid-induced osteoporosis. Hypercalciuria appears to play an important pathologic role in the development of low bone mass, and therefore correction of urine Ca losses should be a primary target for treatment of the bone disease accompanying IH.

  19. Glutamate signalling in bone.

    Directory of Open Access Journals (Sweden)

    Karen eBrakspear

    2012-08-01

    Full Text Available Mechanical loading plays a key role in the physiology of bone, allowing bone to functionally adapt to its environment, however characterisation of the signalling events linking load to bone formation is incomplete. A screen for genes associated with mechanical load-induced bone formation identified the glutamate transporter GLAST, implicating the excitatory amino acid, glutamate, in the mechanoresponse. When an osteogenic load (10N, 10Hz was externally applied to the rat ulna, GLAST (EAAT1 mRNA, was significantly down-regulated in osteocytes in the loaded limb. Functional components from each stage of the glutamate signalling pathway have since been identified within bone, including proteins necessary for calcium-mediated glutamate exocytosis, receptors, transporters and signal propagation. Activation of ionotropic glutamate receptors has been shown to regulate the phenotype of osteoblasts and osteoclasts in vitro and bone mass in vivo. Furthermore, glutamatergic nerves have been identified in the vicinity of bone cells expressing glutamate receptors in vivo. However, it is not yet known how a glutamate signalling event is initiated in bone or its physiological significance. This review will examine the role of the glutamate signalling pathway in bone, with emphasis on the functions of glutamate transporters in osteoblasts.

  20. Blood: bone equilibrium

    Energy Technology Data Exchange (ETDEWEB)

    Neuman, M.W.

    1982-01-01

    The conundrum of blood undersaturation with respect to bone mineralization and its supersaturation with respect to bone's homeostatic function has acquired a new equation. On the supply side, Ca/sup 2 +/ is pumped in across bone cells to provide the needed Ca/sup 2 +/ x P/sub i/ for brushite precipitation. On the demand side, blood is in equilibrium with bone fluid, which is in equilibrium with a mineral more soluble than apatite. The function of potassium in this equation is yet to be found.

  1. Olecranon bone graft: revisited.

    Science.gov (United States)

    Mersa, Berkan; Ozcelik, Ismail Bulent; Kabakas, Fatih; Sacak, Bulent; Aydin, Atakan

    2010-09-01

    Autogenous bone grafts are frequently in use in the field of reconstructive upper extremity surgery. Cancellous bone grafts are applied to traumatic osseous defects, nonunions, defects after the resection of benign bone tumors, arthrodesis, and osteotomy procedures. Cancellous bone grafts do not only have benefits such as rapid revascularization, but they also have mechanical advantages. Despite the proximity to the primary surgical field, cancellous olecranon grafts have not gained the popularity they deserve in the field of reconstructive hand surgery. In this study, the properties, advantages, and technical details of harvesting cancellous olecranon grafts are discussed.

  2. CD34 defines an osteoprogenitor cell population in mouse bone marrow stromal cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Al-Shammary, Asma; Skagen, Peter

    2015-01-01

    Bone marrow stromal cells (BMSCs, also known as bone marrow-derived mesenchymal stem cells) and their progenitors have been identified based on retrospective functional criteria. CD markers are employed to define cell populations with distinct functional characteristics. However, defining and pro...

  3. The role of radioisotopes for the palliation of bone pain from bone metastases

    Institute of Scientific and Technical Information of China (English)

    YANG Ji-gang; LI Chun-lin

    2006-01-01

    Bone metastasis occurs as a result of a complex pathophysiologic process between host and tumor cells leading to cellular invasion, migration adhesion, and stimulation of osteoclastic and osteoblastic activity. Several sequences occur as a result of osseous metastases and resulting bone pain can lead to significant debilitation. Pain associated with osseous metastasis is thought to be distinct from neuropathic or inflammatory pain. Several mechanisms, such as invasion of tumor cells, spinal cord astrogliosis,and sensitization of nervous system, have been postulated to cause pain. Pharmaceutical therapy of bone pain includes nonsteroidal analgesics and opiates. These drags are associated with side effects, and tolerance to these agents necessitates treatment with other modalities. Bisphosphonates act by inhibiting osteoclast-mediated resorption and have been increasingly used in treatment of painful bone metastasis. While external beam radiation therapy remains the mainstay of pain palliation of solitary lesions, bone-seeking radiopharmaceuticals have entered the therapeutic armamentarium for the treatment of multiple painful osseous lesions. 32p has been used for over 3 decades in the treatment of multiple osseous metastases. The myelosuppression caused by this agent has led to the development of other bone-seeking radiopharmaceuticals, including 89SrCl, and 153Sm-ethylenediaminetetramethylene phosphonic acid (153Sm-EDTMP). 89Sr is a bone-seeking radionuclide, whereas 153Sm-EDTMP is a bone-seeking tetraphosphonate; both have been approved by the Food and Drug Administration for the treatment of painful osseous metastases. While both agents have been shown to have efficacy in the treatment of painful osseous metastases from prostate cancer, they may also have utility in the treatment of painful osseous metastases from breast cancer and perhaps from non-small cell lung cancer. This article illustrates the salient features of these radiopharmaceuticals, including the

  4. Maintaining Discrimination in Operation Iraqi Freedom

    Science.gov (United States)

    2008-12-01

    Lockheed Martin, Boeing, or Northrop  Grumman?  Can American troops  blend  in with and weather harsh climates without  specially  made uniforms?  Can...reality of war— unless soldiers fought in the middle of the desert or in the  Antarctic , fighting will always  be near to a civilian population.  The...distinct, fixed symbol, taking into  account insurgent forces that often  blend  in with the civilian population.  The  amendment does, however, still

  5. The effect of Emdogain on the growth and differentiation of rat bone marrow cells.

    NARCIS (Netherlands)

    Dolder, J. van den; Vloon, A.P.; Jansen, J.A.

    2006-01-01

    BACKGROUND AND OBJECTIVE: The major extracellular matrix (ECM) proteins in developing enamel can induce and maintain the formation and mineralization of other skeletal hard tissue, such as bone. Therefore, dental matrix proteins are ideal therapeutic agents when direct formation of functional bone i

  6. Genetic Determinism and the Innate-Acquired Distinction in Medicine.

    Science.gov (United States)

    Kronfeldner, Maria E

    2009-06-01

    This article illustrates in which sense genetic determinism is still part of the contemporary interactionist consensus in medicine. Three dimensions of this consensus are discussed: kinds of causes, a continuum of traits ranging from monogenetic diseases to car accidents, and different kinds of determination due to different norms of reaction. On this basis, this article explicates in which sense the interactionist consensus presupposes the innate-acquired distinction. After a descriptive Part 1, Part 2 reviews why the innate-acquired distinction is under attack in contemporary philosophy of biology. Three arguments are then presented to provide a limited and pragmatic defense of the distinction: an epistemic, a conceptual, and a historical argument. If interpreted in a certain manner, and if the pragmatic goals of prevention and treatment (ideally specifying what medicine and health care is all about) are taken into account, then the innate-acquired distinction can be a useful epistemic tool. It can help, first, to understand that genetic determination does not mean fatalism, and, second, to maintain a system of checks and balances in the continuing nature-nurture debates.

  7. Distinct Kinesin-14 mitotic mechanisms in spindle bipolarity.

    Science.gov (United States)

    Simeonov, Dimitre R; Kenny, Katelyn; Seo, Lan; Moyer, Amanda; Allen, Jessica; Paluh, Janet L

    2009-11-01

    Kinesin-like proteins are integral to formation and function of a conserved mitotic spindle apparatus that directs chromosome segregation and precedes cell division. Ubiquitous to the mechanism of spindle assembly and stability are balanced Kinesin-5 promoting and Kinesin-14 opposing forces. Distinct Kinesin-14 roles in bipolarity in eukaryotes have not been shown, but are suggested by gamma-tubulin-based pole interactions that affect establishment and by microtubule cross-linking and sliding that maintain bipolarity and spindle length. Distinct roles also imply specialized functional domains. By cross-species analysis of compatible mechanisms in establishing mitotic bipolarity we demonstrate that Kinesin-14 human HSET (HsHSET) functionally replaces Schizosaccharomyces pombe Pkl1 and its action is similarly blocked by mutation in a Kinesin-14 binding site on gamma-tubulin. Drosophila DmNcd localizes preferentially to bundled interpolar microtubules in fission yeast and does not replace SpPkl1. Analysis of twenty-six Kinesin-14 derivatives, including Tail, Stalk or Neck-Motor chimeras, for spindle localization, spindle assembly and mitotic progression defined critical domains. The Tail of SpPkl1 contains functional elements enabling its role in spindle assembly that are distinct from but transferable to DmNcd, whereas HsHSET function utilizes both Tail and Stalk features. Our analysis is the first to demonstrate distinct mechanisms between SpPkl1 and DmNcd, and reveal that HsHSET shares functional overlap in spindle pole mechanisms.

  8. Maintaining and troubleshooting your 3D printer

    CERN Document Server

    Bell, Charles

    2014-01-01

    Maintaining and Troubleshooting Your 3D Printer by Charles Bell is your guide to keeping your 3D printer running through preventive maintenance, repair, and diagnosing and solving problems in 3D printing. If you've bought or built a 3D printer such as a MakerBot only to be confounded by jagged edges, corner lift, top layers that aren't solid, or any of a myriad of other problems that plague 3D printer enthusiasts, then here is the book to help you get past all that and recapture the joy of creative fabrication. The book also includes valuable tips for builders and those who want to modify the

  9. Motives for maintaining personal journal blogs.

    Science.gov (United States)

    Hollenbaugh, Erin E

    2011-01-01

    Although much has been learned about political and news blogs, there has been a lack of research on personal journal blogs. They deserve further research attention because of the implications blogs have in many bloggers' immediate social networks, as well as the opportunities for scientific inquiry in a rich and evolving communication environment. This study explored bloggers' motives for maintaining personal journal blogs, or blogs that resemble diaries about one's personal life. Stemming from the uses and gratifications perspective, antecedents (age, sex, loneliness, disclosiveness) and blogging motives composed a model for predicting the amount of blog use. Seven motives emerged from online survey data: helping/informing, social connection, pass time, exhibitionism, archiving/organizing, professionalism, and get feedback. Age, sex, loneliness, and disclosiveness predicted different motives, and the total model (age, sex, loneliness, disclosiveness, and motives) was useful for explaining 13% of the variance in the amount of blog use.

  10. Heartwarming memories: Nostalgia maintains physiological comfort.

    Science.gov (United States)

    Zhou, Xinyue; Wildschut, Tim; Sedikides, Constantine; Chen, Xiaoxi; Vingerhoets, Ad J J M

    2012-08-01

    Nostalgia, a sentimental longing or wistful affection for the past, is a predominantly positive and social emotion. Recent evidence suggests that nostalgia maintains psychological comfort. Here, we propose, and document in five methodologically diverse studies, a broader homeostatic function for nostalgia that also encompasses the maintenance of physiological comfort. We show that nostalgia--an emotion with a strong connotation of warmth--is triggered by coldness. Participants reported stronger nostalgia on colder (vs. warmer) days and in a cold (vs. neutral or warm) room. Nostalgia, in turn, modulates the interoceptive feeling of temperature. Higher levels of music-evoked nostalgia predicted increased physical warmth, and participants who recalled a nostalgic (vs. ordinary autobiographical) event perceived ambient temperature as higher. Finally, and consistent with the close central nervous system integration of temperature and pain sensations, participants who recalled a nostalgic (vs. ordinary autobiographical) event evinced greater tolerance to noxious cold.

  11. [Maintaining solidarity: is mutuality the solution?].

    Science.gov (United States)

    Gevers, J K M; Ploem, M C

    2013-01-01

    Solidarity is essentially the willingness to contribute to the community and its demands, which may even involve contributing more than one is expecting to receive. Another principle is mutuality: this refers to a balance between rights and obligations or between mutual obligations. In its advisory document 'The importance of mutuality......solidarity takes work!', The Dutch Council for Public Health and Health Care underlines the importance of ensuring solidarity within the Dutch health care system, e.g. by encouraging patients to take responsibility for their own health, possibly by introducing elements of mutuality. In our contribution, we comment on the Council's advice. Although we fully agree with the overall conclusion that solidarity should be maintained within the system, we do not see how the introduction of increased mutuality will contribute to this goal.

  12. Maintaining the Telescope Bibliography at Gemini Observatory

    Science.gov (United States)

    Zhang, X.

    2010-10-01

    The library profession benefits tremendously from ever-changing web technologies. In maintaining a telescope bibliography, web-publishing revolutionized the way librarians track relevant publications. Thanks to the search abilities provided by the NASA Astrophysics Data System, arXiv, publishers, as well as Google Scholar, and other such resources, online searching for Gemini-based publications has replaced the tedious perusing of print journals. However, we should keep in mind that online searching is neither flawless nor simple — different content providers require different search strategies. Sometimes the retrievals are not as complete as one expects. Information providers should be constantly improving their searching abilities in order to make the task of electronic publication tracking more reliable and efficient.

  13. How homologous recombination maintains telomere integrity.

    Science.gov (United States)

    Tacconi, Eliana M C; Tarsounas, Madalena

    2015-06-01

    Telomeres protect the ends of linear chromosomes against loss of genetic information and inappropriate processing as damaged DNA and are therefore crucial to the maintenance of chromosome integrity. In addition to providing a pathway for genome-wide DNA repair, homologous recombination (HR) plays a key role in telomere replication and capping. Consistent with this, the genomic instability characteristic of HR-deficient cells and tumours is driven in part by telomere dysfunction. Here, we discuss the mechanisms by which HR modulates the response to intrinsic cellular challenges that arise during telomere replication, as well as its impact on the assembly of telomere protective structures. How normal and tumour cells differ in their ability to maintain telomeres is deeply relevant to the search for treatments that would selectively eliminate cells whose capacity for HR-mediated repair has been compromised.

  14. Maintaining control is team's vital role.

    Science.gov (United States)

    Haywood, Liz; Frankel, Chris; Johns, Andrew

    2011-02-01

    In an environment where there is an ever-increasing use of reliable electronic control, it is easy to become complacent about the need for in-depth knowledge of how the controls actually work. After all, experts who can diagnose and fix such systems are only a phone call away, and a new unit can easily be fitted. Sometimes this is not the case at Bendigo Health, as we have a number of systems with a "black box" set of controls that can take days, or weeks, to fix, and cannot be fixed locally. To better manage and maintain our infrastructure, the Buildings & Infrastructure Department at Bendigo Health includes a number of employees who concentrate on building management systems (BMS). The BMS group plays a vital role in the complete lifecycle of projects that include control and monitoring of the plant within the hospital setting. A good example of this role was in the design, build, installation and commissioning, of two new negative pressure suites at Bendigo Health. The BMS group's involvement in this particular project included the door interlocking, the air conditioning and exhaust fan control, and a comprehensive alarm panel and overrides, all of which can be monitored centrally via the existing BMS system. The involvement of the BMS group, following the DHS guidelines, resulted in the architect and consulting engineers revisiting their designs and improving them to the benefit of both patient care and staff safety. The advantages of projects such as the negative pressure suites installed by the BMS group include the fact that that the hospital gains facilities that work correctly and according to industry guidelines; and the design, installation, and controls of the plant are understood by the people who will be maintaining the infrastructure. This paper will provide an overview of the work undertaken by the BMS group at Bendigo Health, using the negative pressure suites as an exemplar.

  15. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... ionizing radiation to produce pictures of any bone in the body. It is commonly used to diagnose ... bone x-ray makes images of any bone in the body, including the hand, wrist, arm, elbow, ...

  16. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the body. X-rays are the oldest and most frequently used form of medical imaging. A bone ... bones. top of page How should I prepare? Most bone x-rays require no special preparation. You ...

  17. Implementation and Integration of a Finite Element Model into the Bone Remodeling Model to Characterize Skeletal Loading

    Science.gov (United States)

    Werner, C. R.; Lewandowski, B.; Boppana, A.; Pennline, J. A.

    2017-01-01

    NASA's Digital Astronaut Project is developing a bone physiology model to predict changes in bone mineral density over the course of a space mission. The model intends to predict bone loss due to exposure in microgravity as well as predicting bone maintenance due to mechanical stimulus generated by exercise countermeasures. These predictions will be used to inform exercise device efficacy and to help design exercise protocols that will maintain bone mineral density during long exposures to microgravity during spaceflight. The mechanical stimulus and the stresses that are exhibited on the bone are important factors for bone remodeling. These stresses are dependent on the types of exercise that are performed and vary throughout the bone due to the geometry. A primary area of focus for bone health is the proximal femur. This location is critical in transmitting loads between the upper and lower body and have been known to be a critical failure point in older individuals with conditions like osteoporosis.

  18. Nanomaterials promise better bone repair

    OpenAIRE

    Qifei Wang; Jianhua Yan; Junlin Yang; Bingyun Li

    2016-01-01

    Nanomaterials mimicking the nano-features of bones and offering unique smart functions are promising for better bone fracture repair. This review provides an overview of the current state-of-the-art research in developing and using nanomaterials for better bone fracture repair. This review begins with a brief introduction of bone fracture repair processes, then discusses the importance of vascularization, the role of growth factors in bone fracture repair, and the failure of bone fracture rep...

  19. Effect of housing birds in cages or an aviary system on bone characteristics.

    Science.gov (United States)

    Newman, S; Leeson, S

    1998-10-01

    Sixty-nine-week-old brown egg layers were either maintained in cages or moved to a litter-floored aviary system. After 10 or 20 d, birds were selected at random from within each environment, and their tibiae removed. After drying, bones were measured and then subject to various physical measurements of strength and elasticity. Bone ash and bone calcium content were also measured. Birds maintained in an aviary initially had stronger bones as measured by force (P birds had stronger bones, as assessed by force, than their contemporaries maintained in cages. This same relationship was seen in measures of bone stress (P caged birds had bone ash values that were intermediate between birds held only in cages or the aviary (P > 0.05). Bone calcium content was not influenced by the bird's environment. It appears that the skeleton of caged birds can be affected by providing them with an environment that allows opportunity for increased static and dynamic loading of the bones.

  20. BONES, TEACHER'S GUIDE.

    Science.gov (United States)

    Elementary Science Study, Newton, MA.

    THIS GUIDE WAS DEVELOPED FOR USE WITH THE ELEMENTARY SCIENCE STUDY UNIT ON "BONES.""BONES" HAS BEEN TAUGHT IN THE FOURTH GRADE AND REQUIRES FROM 10 TO 25 LESSONS, DEPENDING ON THE NUMBER OF ACTIVITIES USED. THE GUIDE DOES NOT PROVIDE DETAILED INSTRUCTION FOR CONDUCTING CLASSES, BUT RATHER SOME POSSIBLE ACTIVITIES, AND LEAVES THE DAY-TO-DAY…

  1. Children's bone health

    NARCIS (Netherlands)

    I.M. van der Sluis (Inge)

    2002-01-01

    textabstractThe thesis can be divided in two main parts. In the first part (Chapter 2 to 5) bone mineral density, bone metabolism and body composition in healthy children and young adults have been evaluated, while in the second part (Chapter 6 to 10) these issues were studied in children with vario

  2. Biodegradable synthetic bone composites

    Science.gov (United States)

    Liu, Gao; Zhao, Dacheng; Saiz, Eduardo; Tomsia, Antoni P.

    2013-01-01

    The invention provides for a biodegradable synthetic bone composition comprising a biodegradable hydrogel polymer scaffold comprising a plurality of hydrolytically unstable linkages, and an inorganic component; such as a biodegradable poly(hydroxyethylmethacrylate)/hydroxyapatite (pHEMA/HA) hydrogel composite possessing mineral content approximately that of human bone.

  3. Osteotransductive bone cements.

    Science.gov (United States)

    Driessens, F C; Planell, J A; Boltong, M G; Khairoun, I; Ginebra, M P

    1998-01-01

    Calcium phosphate bone cements (CPBCs) are osteotransductive, i.e. after implantation in bone they are transformed into new bone tissue. Furthermore, due to the fact that they are mouldable, their osteointegration is immediate. Their chemistry has been established previously. Some CPBCs contain amorphous calcium phosphate (ACP) and set by a sol-gel transition. The others are crystalline and can give as the reaction product dicalcium phosphate dihydrate (DCPD), calcium-deficient hydroxyapatite (CDHA), carbonated apatite (CA) or hydroxyapatite (HA). Mixed-type gypsum-DCPD cements are also described. In vivo rates of osteotransduction vary as follows: gypsum-DCPD > DCPD > CDHA approximately CA > HA. The osteotransduction of CDHA-type cements may be increased by adding dicalcium phosphate anhydrous (DCP) and/or CaCO3 to the cement powder. CPBCs can be used for healing of bone defects, bone augmentation and bone reconstruction. Incorporation of drugs like antibiotics and bone morphogenetic protein is envisaged. Load-bearing applications are allowed for CHDA-type, CA-type and HA-type CPBCs as they have a higher compressive strength than human trabecular bone (10 MPa).

  4. 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.)

  5. Dysmegakaryocytopoiesis and maintaining platelet count in patients with plasma cell neoplasm

    Directory of Open Access Journals (Sweden)

    Yasmin Mair

    2013-01-01

    Full Text Available Background: Dysmegakaryocytopoiesis in patients with the plasma cell neoplasm (PCN is rarely discussed in the literature. The puzzling phenomenon, which PCN patients maintaining normal platelet count even when the marrow is mostly replaced by plasma cells, is hardly explored. Aim: This study was aimed to determine the frequency of dysmegakaryocytopoiesis in PCN and the relationships between bone marrow (BM plasma cell percentage, plasma cell immunomarkers, the severity of dysmegakaryocytopoiesis, and peripheral blood platelet count in PCN. Materials and Methods: We randomly selected 16 cases of PCN, among which 4 were with monoclonal gammopathy of undetermined significance and 12 were with plasma cell myeloma. Results: Our study showed that: (1 Dysmegakaryocytopoiesis was present in all the selected cases of PCN and its severity was not correlated with the percentage of the plasma cells in BM; (2 almost all patients maintained normal platelet count even when BM was mostly replaced by plasma cells; (3 immunomarkers of the neoplastic plasma cells were not associated with dysmegakaryocytopoiesis or maintaining of platelet count. The possible mechanisms behind dysmegakaryocytopoiesis and maintaining of platelet count were also discussed. Conclusion: Despite the universal presence of dysmegakaryocytopoiesis in PCN, the platelet count is maintained at normal range.

  6. Bone health in children and adolescents with perinatal HIV infection

    Directory of Open Access Journals (Sweden)

    George K Siberry

    2013-06-01

    Full Text Available The long-term impact on bone health of lifelong HIV infection and prolonged ART in growing and developing children is not yet known. Measures of bone health in youth must be interpreted in the context of expected developmental and physiologic changes in bone mass, size, density and strength that occur from fetal through adult life. Low bone mineral density (BMD appears to be common in perinatally HIV-infected youth, especially outside of high-income settings, but data are limited and interpretation complicated by the need for better pediatric norms. The potential negative effects of tenofovir on BMD and bone mass accrual are of particular concern as this drug may be used more widely in younger children. Emphasizing good nutrition, calcium and vitamin D sufficiency, weight-bearing exercise and avoidance of alcohol and smoking are effective and available approaches to maintain and improve bone health in all settings. More data are needed to inform therapies and monitoring for HIV-infected youth with proven bone fragility. While very limited data suggest lack of marked increase in fracture risk for youth with perinatal HIV infection, the looming concern for these children is that they may fail to attain their expected peak bone mass in early adulthood which could increase their risk for fractures and osteoporosis later in adulthood.

  7. Differential Bone Loss in Mouse Models of Colon Cancer Cachexia

    Science.gov (United States)

    Bonetto, Andrea; Kays, Joshua K.; Parker, Valorie A.; Matthews, Ryan R.; Barreto, Rafael; Puppa, Melissa J.; Kang, Kyung S.; Carson, James A.; Guise, Theresa A.; Mohammad, Khalid S.; Robling, Alexander G.; Couch, Marion E.; Koniaris, Leonidas G.; Zimmers, Teresa A.

    2017-01-01

    Cachexia is a distinctive feature of colorectal cancer associated with body weight loss and progressive muscle wasting. Several mechanisms responsible for muscle and fat wasting have been identified, however it is not known whether the physiologic and molecular crosstalk between muscle and bone tissue may also contribute to the cachectic phenotype in cancer patients. The purpose of this study was to clarify whether tumor growth associates with bone loss using several experimental models of colorectal cancer cachexia, namely C26, HT-29, and ApcMin/+. The effects of cachexia on bone structure and strength were evaluated with dual energy X-ray absorptiometry (DXA), micro computed tomography (μCT), and three-point bending test. We found that all models showed tumor growth consistent with severe cachexia. While muscle wasting in C26 hosts was accompanied by moderate bone depletion, no loss of bone strength was observed. However, HT-29 tumor bearing mice showed bone abnormalities including significant reductions in whole-body bone mineral density (BMD), bone mineral content (BMC), femoral trabecular bone volume fraction (BV/TV), trabecular number (Tb.N), and trabecular thickness (Tb.Th), but no declines in strength. Similarly, cachexia in the ApcMin/+ mice was associated with significant decreases in BMD, BMC, BV/TV, Tb.N, and Tb.Th as well as decreased strength. Our data suggest that colorectal cancer is associated with muscle wasting and may be accompanied by bone loss dependent upon tumor type, burden, stage and duration of the disease. It is clear that preserving muscle mass promotes survival in cancer cachexia. Future studies will determine whether strategies aimed at preventing bone loss can also improve outcomes and survival in colorectal cancer cachexia. PMID:28123369

  8. Bone Microstructure of the Stereospondyl Lydekkerina Huxleyi Reveals Adaptive Strategies to the Harsh Post Permian-Extinction Environment.

    Science.gov (United States)

    Canoville, Aurore; Chinsamy, Anusuya

    2015-07-01

    The small-bodied stereospondyl Lydekkerina huxleyi, dominated the amphibian fauna of the South African Lower Triassic. Even though the anatomy of this amphibian has been well described, its growth strategies and lifestyle habits have remained controversial. Previous studies attributed the relative uniformity in skull sizes to a predominance of subadult and adult specimens recovered in the fossil record. Anatomical and taphonomic data suggested that the relatively small body-size of this genus, as compared to its Permo-Triassic relatives, could be linked to a shortened, rapid developmental period as an adaptation to maintain successful breeding populations under harsh environmental conditions. Moreover, Lydekkerina's habitat has been hypothesized to be either aquatic or mainly terrestrial. The current study, utilizes bone microstructure to reassess previous hypotheses pertaining to the biology and ecology of Lydekkerina. Various skeletal elements of different-sized specimens are analyzed to understand its growth dynamics, intraskeletal variability, and lifestyle adaptations. Bone histology revealed that our sample comprises individuals at different ontogenetic stages i.e., juveniles to mature individuals. Our results show that these amphibians, despite exhibiting plasticity in growth, experienced an overall faster growth during early ontogeny (thereby attaining sexual maturity sooner), as compared to most other temnospondyls. The microanatomy of the long bones with their thick bone walls and distinctive medullary cavity suggests that Lydekkerina may have been amphibious with a tendency to be more terrestrial. Our study concludes that Lydekkerina employed a peculiar growth strategy and lifestyle adaptations, which enabled it to endure the harsh, dry conditions of the Early Triassic.

  9. Maintaining boundaries in psychotherapy: Covert narcissistic personality characteristics and psychotherapists.

    Science.gov (United States)

    Luchner, Andrew F; Mirsalimi, Hamid; Moser, Casey J; Jones, Rebecca A

    2008-03-01

    The psychological literature to date has identified more than one form of narcissism: the more well-known grandiose form, and the less familiar and recognized covert form. Although the distinction between these two narcissistic types has been identified with regard to better conceptualizing client dynamics, there has been much less written about how covert narcissistic tendencies and traits may affect psychotherapists and psychotherapy. This paper uses psychodynamic theory to highlight the role that covert narcissistic characteristics may have on the psychotherapists' ability to maintain boundaries, potentially leading to boundary transgressions (existing along a continuum from therapeutically useful to maladaptive and anti-therapeutic). Specific therapeutic situations have been delineated to increase therapists' recognition and awareness of themes that may emerge and compromise the boundaries between themselves and their clients. Areas of focus include narcissism and its forms, the possible connection between covert narcissism in psychotherapists and the impact on managing boundaries, the potential therapeutic implications of covert narcissistic tendencies in psychotherapists, and the implications of covert narcissistic personality characteristics on treatment, supervision, and training. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  10. Translational activation maintains germline tissue homeostasis during adulthood.

    Science.gov (United States)

    Nousch, Marco; Eckmann, Christian R

    2015-01-01

    Adult tissue maintenance is achieved through a tightly controlled equilibrium of 2 opposing cell fates: stem cell proliferation and differentiation. In recent years, the germ line emerged as a powerful in vivo model tissue to investigate the underlying gene expression mechanisms regulating this balance. Studies in numerous organisms highlighted the prevalence of post-transcriptional mRNA regulation, which relies on RNA-targeting factors that influence mRNA fates (e.g. decay or translational efficiency). Conserved translational repressors were identified that build negative feedback loops to ensure one or the other cell fate. However, to facilitate a fast and efficient transition between 2 opposing cell fates, translational repression per se appears not to be sufficient, suggesting the involvement of additional modes of gene expression regulation. Cytoplasmic poly(A) polymerases (cytoPAPs) represent a unique class of post-transcriptional mRNA regulators that modify mRNA 3' ends and positively influence cytoplasmic mRNA fates. We recently discovered that the 2 main cytoPAPs, GLD-2 and GLD-4, use distinct mechanisms to promote gene expression and that cytoPAP-mediated mRNA activation is important for regulating the size of the proliferative germ cell pool in the adult Caenorhabditis elegans gonad. Here, we comment on the different mechanisms of the 2 cytoPAPs as translational activators in germ cell development and focus on their biological roles in maintaining the balance between germline stem cell proliferation and differentiation in the Caenorhabditis elegans gonad.

  11. Aneurysmal bone cyst: Rarity in mandible and its ambiguity with Central giant cell granuloma

    Directory of Open Access Journals (Sweden)

    Anagha Shete

    2012-01-01

    Full Text Available The aneurysmal bone cyst is an uncommon lesion which has been found in most bones of the skeleton, although the majority occur in the long bones and in the spine. It was first described as a distinct clinical entity by Jaffe and Lichenstein in 1942 to describe the -characteristic "blow-out" of the bone seen in the radiographs of the lesion. In the past, the lesion has been classified as an atypical giant cell tumor or benign bone cyst. We report a case of an aneurysmal bone cyst in an 18-year-old patient who reported with the chief complaint of swelling on the right side of the face since 4 months. It was non-tender, non-fluctuant, and hard in consistency. Radiographic examination revealed a large, expansile, multilocular lesion suggestive of benign odontogenic tumor. Complete enucleation was carried out and the final histopathologic diagnosis of aneurysmal bone cyst was given.

  12. Bacteriological evaluation of bone grafts stored by cryogenic freezing at –24°C from a canine (Canis familiaris bone bank

    Directory of Open Access Journals (Sweden)

    Jaqueline França dos Santos

    2015-12-01

    Full Text Available The scientific basis of bone transplantation was established during the mid-nineteenth century, when the osteogenic properties of the bone and periosteum, beneficial influence of cold preservation of bones, and first conventional attempt to store bones for elective use, were described. A bone bank has several advantages, such as the immediate availability of grafts in large quantities, and different shapes and sizes, and maintenance of osteoinductive activity in grafts. In addition, it reduces patient blood loss, surgical time, and quantity of anesthetics required. Clinical applications include the correction of comminuted fractures, treatment of non-union bones, and replacement of bone loss due to infections or malignancies. The success of these procedures depends on the preservation and integrity of the graft. This study aimed to evaluate the feasibility of maintaining a canine bone bank (Canis familiaris by quantifying the bacterial contamination of bone grafts preserved at –24°C. The samples were evaluated through a monthly assessment of bacteriological cultures over a period of 6 months. The harvest method was efficient and sterile, reducing the risk of contamination. We conclude that the techniques chosen for the implementation of a bone bank were effective and feasible (use of a common freezer reaching a temperature below –24°C. The viability of the bones was attested during a 6-month period, and the samples demonstrated a 100% sterility rate.

  13. MAVS maintains mitochondrial homeostasis via autophagy

    Science.gov (United States)

    Sun, Xiaofeng; Sun, Liwei; Zhao, Yuanyuan; Li, Ying; Lin, Wei; Chen, Dahua; Sun, Qinmiao

    2016-01-01

    Mitochondrial antiviral signalling protein (MAVS) acts as a critical adaptor protein to transduce antiviral signalling by physically interacting with activated RIG-I and MDA5 receptors. MAVS executes its functions at the outer membrane of mitochondria to regulate downstream antiviral signalling, indicating that the mitochondria provides a functional platform for innate antiviral signalling transduction. However, little is known about whether and how MAVS-mediated antiviral signalling contributes to mitochondrial homeostasis. Here we show that the activation of MAVS is sufficient to induce autophagic signalling, which may mediate the turnover of the damaged mitochondria. Importantly, we find MAVS directly interacts with LC3 through its LC3-binding motif ‘YxxI’, suggesting that MAVS might act as an autophagy receptor to mediate mitochondrial turnover upon excessive activation of RLR signalling. Furthermore, we provide evidence that both MAVS self-aggregation and its interaction with TRAF2/6 proteins are important for MAVS-mediated mitochondrial turnover. Collectively, our findings suggest that MAVS acts as a potential receptor for mitochondria-associated autophagic signalling to maintain mitochondrial homeostasis. PMID:27551434

  14. Challenges in implementing and maintaining osteoporosis therapy

    Directory of Open Access Journals (Sweden)

    Modi A

    2014-08-01

    Full Text Available Ankita Modi,1 Shiva Sajjan,1 Sampada Gandhi2 1Center for Observational and Real-World Evidence, Merck & Co., Inc., Whitehouse Station, NJ, USA; 2School of Public Health, Rutgers University, Piscataway, NJ, USA Abstract: In the United States, an estimated 19% of older men and 30% of older women are at elevated risk of osteoporotic fracture and considered to be eligible for treatment. The burden of osteoporosis is similar in Europe and is projected to rise worldwide, with aging populations and increasing fracture rates accompanying urbanization. Notwithstanding its high prevalence, osteoporosis is often underdiagnosed and undertreated. Moreover, even when the diagnosis is made and the decision is taken to treat, there are remaining challenges in implementing therapy for osteoporosis. Several patient populations are particularly challenging for clinicians to treat and require further study with regard to osteoporosis therapy. These include the very elderly, who face challenges relating to adherence; men, in whom osteoporosis remains under-recognized; patients with glucocorticoid-induced osteoporosis or renal impairment, who are at increased risk of fracture; patients with preexisting gastrointestinal problems who cannot tolerate existing orally administered osteoporosis therapies; and high-risk patients who show inadequate response to therapy. Moreover, poor adherence and poor persistence with osteoporosis medications are common and result in an increased risk of fracture, higher medical costs, and increased hospitalizations. Once the decision to institute therapy is made, patient education about osteoporosis and fracture risk should be provided. This is particularly important for men, who may not be aware that osteoporosis can be a concern. Secondary prevention programs, including fracture liaison services and bone therapy groups, can help to improve adherence to therapy. Further study is needed to guide the treatment of men, the very elderly

  15. Fabrication and characterization of electrospun osteon mimicking scaffolds for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Andric, T. [Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Sampson, A.C. [Chemical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Freeman, J.W., E-mail: jwfreeman@vt.edu [Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)

    2011-01-01

    Skeletal loss and bone deficiencies are a major worldwide problem with over 600,000 procedures performed in the US alone annually, making bone one of the most transplanted tissues, second to blood only. Bone is a composite tissue composed of organic matrix, inorganic bone mineral, and water. Structurally bone is organized into two distinct types: trabecular (or cancellous) and cortical (or compact) bones. Trabecular bone is characterized by an extensive interconnected network of pores. Cortical bone is composed of tightly packed units, called osteons, oriented parallel along to the axis of the bone. While the majority of scaffolds attempt to replicate the structure of the trabecular bone, fewer attempts have been made to create scaffolds to mimic the structure of cortical bone. The aim of this study was to develop a technique to fabricate scaffolds that mimic the organization of an osteon, the structural unit of cortical bone. We successfully built a rotating stage for PGA fibers and utilized it for collecting electrospun nanofibers and creating scaffolds. Resulting scaffolds consisted of concentric layers of electrospun PLLA or gelatin/PLLA nanofibers wrapped around PGA microfiber core with diameters that ranged from 200 to 600 {mu}m. Scaffolds were mineralized by incubation in 10x simulated body fluid, and scaffolds composed of 10%gelatin/PLLA had significantly higher amounts of calcium phosphate. The electrospun scaffolds also supported cellular attachment and proliferation of MC3T3 cells over the period of 28 days.

  16. Establishing and maintaining cell polarity with mRNA localization in Drosophila.

    Science.gov (United States)

    Barr, Justinn; Yakovlev, Konstantin V; Shidlovskii, Yulii; Schedl, Paul

    2016-03-01

    How cell polarity is established and maintained is an important question in diverse biological contexts. Molecular mechanisms used to localize polarity proteins to distinct domains are likely context-dependent and provide a feedback loop in order to maintain polarity. One such mechanism is the localized translation of mRNAs encoding polarity proteins, which will be the focus of this review and may play a more important role in the establishment and maintenance of polarity than is currently known. Localized translation of mRNAs encoding polarity proteins can be used to establish polarity in response to an external signal, and to maintain polarity by local production of polarity determinants. The importance of this mechanism is illustrated by recent findings, including orb2-dependent localized translation of aPKC mRNA at the apical end of elongating spermatid tails in the Drosophila testis, and the apical localization of stardust A mRNA in Drosophila follicle and embryonic epithelia.

  17. Mechanotransduction by bone cells in vitro: mechanobiology of bone tissue

    NARCIS (Netherlands)

    Mullender, M.; El Haj, A.J.; Yang, Y.; van Duin, M.A.; Burger, E.H.; Klein-Nulend, J.

    2004-01-01

    Mechanical force plays an important role in the regulation of bone remodelling in intact bone and bone repair. In vitro, bone cells demonstrate a high responsiveness to mechanical stimuli. Much debate exists regarding the critical components in the load profile and whether different components, such

  18. Perfluorodecalin and bone regeneration

    Directory of Open Access Journals (Sweden)

    F Tamimi

    2013-01-01

    Full Text Available Perfluorodecalin (PFD is a chemically and biologically inert biomaterial and, as many perfluorocarbons, is also hydrophobic, radiopaque and has a high solute capacity for gases such as oxygen. In this article we have demonstrated, both in vitro and in vivo, that PFD may significantly enhance bone regeneration. Firstly, the potential benefit of PFD was demonstrated by prolonging the survival of bone marrow cells cultured in anaerobic conditions. These findings translated in vivo, where PFD incorporated into bone-marrow-loaded 3D-printed scaffolds substantially improved their capacity to regenerate bone. Secondly, in addition to biological applications, we have also shown that PFD improves the radiopacity of bone regeneration biomaterials, a key feature required for the visualisation of biomaterials during and after surgical implantation. Finally, we have shown how the extreme hydrophobicity of PFD enables the fabrication of highly cohesive self-setting injectable biomaterials for bone regeneration. In conclusion, perfluorocarbons would appear to be highly beneficial additives to a number of regenerative biomaterials, especially those for bone regeneration.

  19. Bone health in adults treated with endocrine therapy for early breast or prostate cancer.

    Science.gov (United States)

    Van Poznak, Catherine H

    2015-01-01

    Bone is a hormonally responsive organ. Sex hormones and calcium regulating hormones, including parathyroid hormone, 1-25 dihydroxy vitamin D, and calcitonin, have effects on bone resorption and bone deposition. These hormones affect both bone quality and bone quantity. The sex hormone estrogen inhibits bone resorption, and estrogen therapy has been developed to prevent and treat osteoporosis. Androgens are an important source of estrogen through the action of the enzyme aromatase and may themselves stimulate bone formation. Hence, the sex steroids play a role in bone metabolism. Breast cancer and prostate cancer are frequently hormonally responsive and may be treated with antiestrogens or antiandrogens respectfully. In addition, chemotherapy and supportive medications may alter the patient's endocrine system. In general, the suppression of sex hormones has a predictable affect on bone health, as seen by loss of bone mineral density and increased risk of fragility fractures. The bone toxicity of cancer-directed endocrine therapy can be mitigated through screening, counseling on optimization of calcium and vitamin D intake, exercise, and other lifestyle/behavioral actions, as well as the use of medications when the fracture risk is high. Maintaining bone health in patients who are treated with endocrine therapy for breast and prostate cancer is the focus of this review.

  20. Imaging Paget's disease of bone--from head to toe.

    Science.gov (United States)

    Cortis, K; Micallef, K; Mizzi, A

    2011-07-01

    Paget's disease of the bone is a common, non-inflammatory, metabolic, skeletal disorder of unknown aetiology characterized by an increase in osteoclast-mediated bone resorption and compensatory excessive osteoblast activation. Prevalence increases with age, and a pronounced geographical variation is well documented. The disease is often an incidental finding on a radiological examination requested for an unrelated indication. The osteolytic, mixed osteolytic/osteoblastic, and osteosclerotic phases may occur in the same patient and same bone in a synchronous or metachronous fashion. Radiological features in each phase mirror the histopathological appearances, and are distinctive enough to establish a diagnosis with confidence. Using multi-technique imaging, this review illustrates the most common and the not so common radiological patterns of involvement in Paget's disease of bone observed at our centre during the past 20 years.

  1. Bone Proteoglycan Changes During Skeletal Unloading

    Science.gov (United States)

    Yamauchi, M.; Uzawa, K.; Pornprasertsuk, S.; Arnaud, S.; Grindeland, R.; Grzesik, W.

    1999-01-01

    Skeletal adaptability to mechanical loads is well known since the last century. Disuse osteopenia due to the microgravity environment is one of the major concerns for space travelers. Several studies have indicated that a retardation of the mineralization process and a delay in matrix maturation occur during the space flight. Mineralizing fibrillar type I collagen possesses distinct cross-linking chemistries and their dynamic changes during mineralization correlate well with its function as a mineral organizer. Our previous studies suggested that a certain group of matrix proteoglycans in bone play an inhibitory role in the mineralization process through their interaction with collagen. Based on these studies, we hypothesized that the altered mineralization during spaceflight is due in part to changes in matrix components secreted by cells in response to microgravity. In this study, we employed hindlimb elevation (tail suspension) rat model to study the effects of skeletal unloading on matrix proteoglycans in bone.

  2. Pregnancy, Breastfeeding, and Bone Health

    Science.gov (United States)

    ... need for calcium. During pregnancy, women produce more estrogen, a hormone that protects bones. Any bone mass lost during pregnancy is typically ... mass during breastfeeding because they’re producing less estrogen, which is the hormone that protects bones. The good news is that, like bone lost ...

  3. Oral Health and Bone Disease

    Science.gov (United States)

    ... low bone mass. Research suggests a link between osteoporosis and bone loss in the jaw. The bone in the jaw supports and anchors the teeth. When the jawbone becomes less dense, tooth loss can occur, a common occurrence in older adults. Skeletal Bone Density and Dental Concerns Periodontal Disease ...

  4. Programmed administration of parathyroid hormone increases bone formation and reduces bone loss in hindlimb-unloaded ovariectomized rats

    Science.gov (United States)

    Turner, R. T.; Evans, G. L.; Cavolina, J. M.; Halloran, B.; Morey-Holton, E.

    1998-01-01

    Gonadal insufficiency and reduced mechanical usage are two important risk factors for osteoporosis. The beneficial effects of PTH therapy to reverse the estrogen deficiency-induced bone loss in the laboratory rat are well known, but the influence of mechanical usage in this response has not been established. In this study, the effects of programed administration of PTH on cancellous bone volume and turnover at the proximal tibial metaphysis were determined in hindlimb-unloaded, ovariectomized (OVX), 3-month-old Sprague-Dawley rats. PTH was administered to weight-bearing and hindlimb-unloaded OVX rats with osmotic pumps programed to deliver 20 microg human PTH (approximately 80 microg/kg x day) during a daily 1-h infusion for 7 days. Compared with sham-operated rats, OVX increased longitudinal and radial bone growth, increased indexes of cancellous bone turnover, and resulted in net resorption of cancellous bone. Hindlimb unloading of OVX rats decreased longitudinal and radial bone growth, decreased osteoblast number, increased osteoclast number, and resulted in a further decrease in cancellous bone volume compared with those in weight-bearing OVX rats. Programed administration of PTH had no effect on either radial or longitudinal bone growth in weight-bearing and hindlimb-unloaded OVX rats. PTH treatment had dramatic effects on selected cancellous bone measurements; PTH maintained cancellous bone volume in OVX weight-bearing rats and greatly reduced cancellous bone loss in OVX hindlimb-unloaded rats. In the latter animals, PTH treatment prevented the hindlimb unloading-induced reduction in trabecular thickness, but the hormone was ineffective in preventing either the increase in osteoclast number or the loss of trabecular plates. Importantly, PTH treatment increased the retention of a baseline flurochrome label, osteoblast number, and bone formation in the proximal tibial metaphysis regardless of the level of mechanical usage. These findings demonstrate that

  5. EXERCISE AND BONE MINERAL ACCRUAL IN CHILDREN AND ADOLESCENTS

    Directory of Open Access Journals (Sweden)

    Melonie Burrows

    2007-09-01

    Full Text Available Osteoporosis is a serious skeletal disease causing an increase in morbidity and mortality through its association with age-related fractures. Although most effort in fracture prevention has been directed at retarding the rate of age-related bone loss and reducing the frequency and severity of trauma among elderly people, evidence is growing that peak bone mass is an important contributor to bone strength during later life. Indeed, there has been a large emphasis on the prevention of osteoporosis through the optimization of peak bone mass during childhood and adolescence. The prepubertal human skeleton is sensitive to the mechanical stimulation elicited by exercise and there is increasing evidence that regular weight-bearing exercise is an effective strategy for enhancing bone mineral throughout growth. Physical activity or participation in sports needs to start at prepubertal ages and be maintained through pubertal development to obtain the maximal peak bone mass achievable. High strain eliciting sports like gymnastics, or participation in sports or weight bearing physical activity like soccer, are strongly recommended to increase peak bone mass. Many other factors also influence the accumulation of bone mineral during childhood and adolescence, including heredity, gender, diet and endocrine status. However, this review article will focus solely on the effects of physical activity and exercise providing a summary of current knowledge on the interplay between activity, exercise and bone mass development during growth. Due to the selection bias and other confounding factors inherent in cross-sectional studies, longitudinal and intervention studies only will be reviewed for they provide a greater opportunity to examine the influence of mechanical loading on bone mineral accretion over time

  6. Osteopetrosis (marble bone disease

    Directory of Open Access Journals (Sweden)

    Alexey Nikolayevich Kalyagin

    2014-01-01

    Full Text Available We report the data of the history of describing osteopetrosis (marble bone disease, its clinical features, diagnosis, and possible therapy approaches. Our own clinical case is presented.

  7. Petrous Bone Cholesteatoma

    Science.gov (United States)

    Sanna, Mario; Zini, Carlo; Gamoletti, Roberto; Frau, Niccolò; Taibah, Abdel Kader; Russo, Alessandra; Pasanisi, Enrico

    1993-01-01

    Petrous bone cholesteatoma is a rare pathologic entity and may be a difficult surgical challenge because of potential involvement of the facial nerve, carotid artery, dura mater, otic capsule, and risk of cerebrospinal fluid leak. The objective of this article is to present a personal classification of petrous bone cholesteatomas, a survey of recent surgical attitudes, and our present surgical strategy based on our experience with 54 operations between 1978 and 1990. Radical petromastoid exenteration with marsupialization and the middle cranial fossa approach were used only for small pure infra- or supralabyrinthine cholesteatomas, respectively. The enlarged transcochlear approach with closure of the external auditory canal was used for infralabyrinthine, infralabyrinthine-apical, and massive petrous bone cholesteatomas. Five cases with petrous bone cholesteatomas in different locations are described in detail to present the signs and symptoms together with the management. ImagesFigure 10Figure 11Figure 12Figure 13Figure 14Figure 15Figure 16Figure 17Figure 18 PMID:17170912

  8. Metastatic Bone Disease

    Science.gov (United States)

    ... begin in bone are much less common in adults older than 45 years. Other diseases, such as Paget’s sarcoma, post-radiation sarcoma, hyperparathyroidism, and fractures due to osteoporosis, are also possibilities. Additional tests will likely be ...

  9. Plain film and CT observations in prostaglandin-induced bone changes

    Energy Technology Data Exchange (ETDEWEB)

    Matzinger, M.A.; Briggs, V.A.; Dunlap, H.J.; Udjus, K.; Martin, D.J.; McDonald, P. (Children' s Hospital of Eastern Ontario, Ottawa, ON (Canada). Dept. of Radiology)

    1992-08-01

    Prostaglandin E[sub 1] intravenous infusion is used in infants with ductal-dependent cogenital heart disease to maintain ductal patency and prolong life until palliative or corrective surgery is feasible. Complications of prostaglandin administration include fever, diarrhoea, hypotension, apnoea, bradycardia, pseudowidening of the cranial sutures, underossification of the calvarial bones, periostitis, and skin edema. This paper presents dramatic plain radiographic features of prostaglandin-induced bone disease, inlcuding periosteal proliferation and the unusual bone-within-bone apperance, and provides the previously unpublished CT correlation. (orig.).

  10. SHEEP TEMPORAL BONE

    Directory of Open Access Journals (Sweden)

    Kesavan

    2016-03-01

    Full Text Available INTRODUCTION Human temporal bones are difficult to procure now a days due to various ethical issues. Sheep temporal bone is a good alternative due to morphological similarities, easy to procure and less cost. Many middle ear exercises can be done easily and handling of instruments is done in the procedures like myringoplasty, tympanoplasty, stapedotomy, facial nerve dissection and some middle ear implants. This is useful for resident training programme.

  11. 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.

  12. Successful treatment of a humeral capitulum osteonecrosis with bone morphogenetic protein-7 combined with autologous bone grafting.

    Science.gov (United States)

    Marsell, Richard; Hailer, Nils P

    2014-08-01

    We present the case of a 27-year-old female with subcortical osteonecrosis of the humeral capitulum. Percutaneous retrograde drilling of the lesion and application of recombinant human bone morphogenetic protein (BMP)-7 were combined with autologous bone grafting. At follow-up the patient was almost pain-free, had normalized her range of motion, and radiography showed consolidation of the lesion without any heterotopic bone formation. By timing surgery prior to subchondral collapse, biomechanical stability of the subchondral bone was maintained. To our knowledge, this is the first report on the treatment of an osteonecrosis in this location with a BMP, and this strategy could potentially be applied in other locations with juxta-articular osteonecrosis.

  13. GLP-1 receptor agonist treatment increases bone formation and prevents bone loss in weight-reduced obese women

    DEFF Research Database (Denmark)

    Iepsen, Eva Pers Winning; Lundgren, Julie Rehné; Hartmann, Bolette

    2015-01-01

    bone mass reductions. DESIGN: Randomized control study. SETTING: Out-patient research hospital clinic. PARTICIPANTS: Thirty-seven healthy obese women. BMI 34±0.5 kg/m(2), age 46±2 years. INTERVENTION: After a low-calorie diet-induced 12% weight loss, participants were randomized to treatment...... with or without administration of the GLP-1 RA liraglutide (1.2mg/day) for 52 weeks. In case of weight gain, up to two meals per day could be substituted with a low-calorie diet product in order to maintain the weight loss. MAIN OUTCOME MEASURES: Total, pelvic and arm-leg bone mineral content (BMC) and bone......% and prevented bone loss after weight loss obtained through a low calorie-diet, supporting its role as a safe weight-lowering agent....

  14. 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.

  15. Polymeric scaffolds as stem cell carriers in bone repair.

    Science.gov (United States)

    Rossi, Filippo; Santoro, Marco; Perale, Giuseppe

    2015-10-01

    Although bone has a high potential to regenerate itself after damage and injury, the efficacious repair of large bone defects resulting from resection, trauma or non-union fractures still requires the implantation of bone grafts. Materials science, in conjunction with biotechnology, can satisfy these needs by developing artificial bones, synthetic substitutes and organ implants. In particular, recent advances in polymer science have provided several innovations, underlying the increasing importance of macromolecules in this field. To address the increasing need for improved bone substitutes, tissue engineering seeks to create synthetic, three-dimensional scaffolds made from polymeric materials, incorporating stem cells and growth factors, to induce new bone tissue formation. Polymeric materials have shown a great affinity for cell transplantation and differentiation and, moreover, their structure can be tuned in order to maintain an adequate mechanical resistance and contemporarily be fully bioresorbable. This review emphasizes recent progress in polymer science that allows relaible polymeric scaffolds to be synthesized for stem cell growth in bone regeneration.

  16. Bone Remodeling Monitor

    Science.gov (United States)

    Foucar, Charlie; Goldberg, Leslie; Hon, Bodin; Moore, Shannon; Williams, Evan

    2009-01-01

    The impact of bone loss due to different mechanical loadings in microgravity is a major concern for astronauts upon reintroduction to gravitational forces in exploration missions to the Moon and Mars. it has been shown that astronauts not only lose bone at differing rates, with levels up to 2% per month, but each astronaut will respond to bone loss treatments differently. Pre- and post-flight imaging techniques and frozen urine samples for post-flight laboratory immunoassays To develop a novel, non-invasive, highly . sensitive, portable, intuitive, and low-powered device to measure bone resorption levels in 'real time' to provide rapid and Individualized feedback to maximize the efficacy of bone loss countermeasures 1. Collect urine specimen and analyze the level of bone resorption marker, DPD (deoxypridinoline) excreted. 2. Antibodies specific to DPD conjugated with nanoshells and mixed with specimen, the change in absorbance from agglutination is measured by an optical device. 3. The concentration of DPD is displayed and recorded on a PDA

  17. Guided bone regeneration : the influence of barrier membranes on bone grafts and bone defects

    NARCIS (Netherlands)

    Gielkens, Pepijn Frans Marie

    2008-01-01

    Guided bone regeneration (GBR) can be described as the use of a barrier membrane to provide a space available for new bone formation in a bony defect. The barrier membrane protects the defect from in-growth of soft tissue cells and allows bone progenitor cells to develop bone within a blood clot tha

  18. [Experimental study of poly-DL-lactic acid membrane guided bone regeneration in rabbit radii bone defects].

    Science.gov (United States)

    Duan, Hong; Fan, Yubo; Dou, Jun; Pei, Fuxing

    2004-10-01

    This study was conducted to observe bone regeneration guided by poly-DL-latic acid (PDLLA) membrane in rabbit radii bone defects and to explore the mechanism of the membrane guided bone regeneration (MGBR). The animal models of bony and periosteous defects were established in both radii of 40 adult New Zealand white rabbits. The left defect as the experimental side was bridged with PDLLA membrane tube, the right side as the controlled side was untreated. The specimens were collected at 2, 4, 8 and 12 weeks postoperatively. General observation, X-ray, histological observation and biomechanical examination were applied to the repair of the models of MGBR in both groups. Two weeks after operation, with much new bony callus formed outside the tube at both fragments, the membrane tube covered with connective tissues was filled with haematoma and fibrous callus. Twelve weeks after operation, the PDLLA membrane became white and its tube shape was still maintained. However, new bone callus outside the tube almost completely disappeared, and inside the tubes all radii bone defects were successfully repaired with bony union. On the controlled sides, bone defects were filled with connective tissues 2 weeks postoperatively. And 12 weeks after operation, the typical nonunion that had been formed after bone marrow canals were sealed with cortical bone. On the experimental side, the strength of the newly formed bone at the 12th week was higher than that at the 8th week (Pregeneration could be successfully guided by PDLLA membrane, and this MGBR technique might be generally used in the treatment of bone defects and nonunion.

  19. Evidence for a Distinct Kind of Noun.

    Science.gov (United States)

    Soja, Nancy N.

    1994-01-01

    Examined the spontaneous speech of four children and their parents for use of determiners with NP-type nouns and count nouns. Found that the parents made a clear distinction between the two kinds of nouns, omitting determiners with the NP-type nouns but not with the count nouns. The children all made the same distinction by four years of age. (HTH)

  20. In situ formation of porous space maintainers in a composite tissue defect.

    Science.gov (United States)

    Spicer, Patrick P; Kretlow, James D; Henslee, Allan M; Shi, Meng; Young, Simon; Demian, Nagi; Jansen, John A; Wong, Mark E; Mikos, Antonios G; Kasper, F Kurtis

    2012-04-01

    Reconstruction of composite defects involving bone and soft tissue presents a significant clinical challenge. In the craniofacial complex, reconstruction of the soft and hard tissues is critical for both functional and aesthetic outcomes. Constructs for space maintenance provide a template for soft tissue regeneration, priming the wound bed for a definitive repair of the bone tissue with greater success. However, materials used clinically for space maintenance are subject to poor soft tissue integration, which can result in wound dehiscence. Porous materials in space maintenance applications have been previously shown to support soft tissue integration and to allow for drug release from the implant to further prepare the wound bed for definitive repair. This study evaluated solid and low porosity (16.9% ± 4.1%) polymethylmethacrylate space maintainers fabricated intraoperatively and implanted in a composite rabbit mandibular defect model for 12 weeks. The data analyses showed no difference in the solid and porous groups both histologically, evaluating the inflammatory response at the interface and within the pores of the implants, and grossly, observing the healing of the soft tissue defect over the implant. These results demonstrate the potential of porous polymethylmethacrylate implants formed in situ for space maintenance in the craniofacial complex, which may have implications in the potential delivery of therapeutic drugs to prime the wound site for a definitive bone repair.

  1. Biomarkers of bone and mineral metabolism following bone marrow transplantation.

    Science.gov (United States)

    Baek, Ki Hyun; Kang, Moo Il

    2009-01-01

    The loss of bone mass often occurs after patients undergo bone marrow transplantation (BMT). The rapid impairment of bone formation and the increase in bone resorption, as mirrored by the biochemical markers of bone turnover, might play a role in this bone loss, and especially during the immediate post-BMT period. The possible direct causes for this paradoxical uncoupling are exposure to immunosuppressants, hypogonadism, the changes of cytokines, the changes of the bone growth factors, and the damage to the osteoprogenitor cells because of myeloablative therapy. In this chapter, we discuss the general aspects of post-BMT bone loss with a peculiar focus on the remodeling imbalance of bone and its relation to the use of immunosuppressants and the changes of sex hormones, growth factors, and cytokines.

  2. Characterizing the inorganic/organic interface in cancer bone metastasis

    Science.gov (United States)

    Wu, Fei

    Bone metastasis frequently occurs in patients with advanced breast cancer and remains a major source of mortality. At the molecular level, bone is a nanocomposite composed of inorganic bone mineral deposited within an organic extracellular matrix (ECM). Although the exact mechanisms of bone metastasis remain unclear, the nanoscale materials properties of bone mineral have been implicated in this process. Bone apatite is closely related to synthetic hydroxyapatite (HAP, Ca10(PO4)6(OH)2) in terms of structural and mechanical properties. Additionally, although the primary protein content of bone is collagen I, the glycoprotein fibronectin (Fn) is essential in maintaining the overall integrity of the bone matrix. Importantly, in vivo, neither breast cancer cells nor normal bone cells interact directly with the bone mineral but rather with the protein film adsorbed onto the mineral surface. Therefore, we hypothesized that breast cancer cell functions were regulated by differential fibronectin adsorption onto hydroxyapatite, which led to pathological remodeling of the bone matrix and sustained bone metastasis. Three model systems containing HAP and Fn were developed for this thesis. In model system I, a library of synthetic HAP nanoparticles were utilized to investigate the effect of mineral size, shape, and crystallinity on Fn conformation, using Forster resonance energy transfer (FRET) spectroscopy. In model system II, Fn-functionalized large geologic HAP crystals were used instead of HAP nanoparticles to avoid cellular uptake when investigating subsequent cell functions. Overall our FRET analysis (models I and II) revealed that Fn conformation depended on size, surface chemistry, and roughness of underlying HAP. When breast cancer cells were seeded on the Fn-coated HAP crystal facets (model II), our data indicated high secretion levels of proangiogenic and proinflammatory factors associated with the presence of unfolded Fn conformations, likely caused by differential

  3. Long bone histology and growth patterns in ankylosaurs: implications for life history and evolution.

    Science.gov (United States)

    Stein, Martina; Hayashi, Shoji; Sander, P Martin

    2013-01-01

    The ankylosaurs are one of the major dinosaur groups and are characterized by unique body armor. Previous studies on other dinosaur taxa have revealed growth patterns, life history and evolutionary mechanisms based on their long bone histology. However, to date nothing is known about long bone histology in the Ankylosauria. This study is the first description of ankylosaurian long bone histology based on several limb elements, which were sampled from different individuals from the Ankylosauridae and Nodosauridae. The histology is compared to that of other dinosaur groups, including other Thyreophora and Sauropodomorpha. Ankylosaur long bone histology is characterized by a fibrolamellar bone architecture. The bone matrix type in ankylosaurs is closest to that of Stegosaurus. A distinctive mixture of woven and parallel-fibered bone together with overall poor vascularization indicates slow growth rates compared to other dinosaurian taxa. Another peculiar characteristic of ankylosaur bone histology is the extensive remodeling in derived North American taxa. In contrast to other taxa, ankylosaurs substitute large amounts of their primary tissue early in ontogeny. This anomaly may be linked to the late ossification of the ankylosaurian body armor. Metabolically driven remodeling processes must have liberated calcium to ossify the protective osteodermal structures in juveniles to subadult stages, which led to further remodeling due to increased mechanical loading. Abundant structural fibers observed in the primary bone and even in remodeled bone may have improved the mechanical properties of the Haversian bone.

  4. Long bone histology and growth patterns in ankylosaurs: implications for life history and evolution.

    Directory of Open Access Journals (Sweden)

    Martina Stein

    Full Text Available The ankylosaurs are one of the major dinosaur groups and are characterized by unique body armor. Previous studies on other dinosaur taxa have revealed growth patterns, life history and evolutionary mechanisms based on their long bone histology. However, to date nothing is known about long bone histology in the Ankylosauria. This study is the first description of ankylosaurian long bone histology based on several limb elements, which were sampled from different individuals from the Ankylosauridae and Nodosauridae. The histology is compared to that of other dinosaur groups, including other Thyreophora and Sauropodomorpha. Ankylosaur long bone histology is characterized by a fibrolamellar bone architecture. The bone matrix type in ankylosaurs is closest to that of Stegosaurus. A distinctive mixture of woven and parallel-fibered bone together with overall poor vascularization indicates slow growth rates compared to other dinosaurian taxa. Another peculiar characteristic of ankylosaur bone histology is the extensive remodeling in derived North American taxa. In contrast to other taxa, ankylosaurs substitute large amounts of their primary tissue early in ontogeny. This anomaly may be linked to the late ossification of the ankylosaurian body armor. Metabolically driven remodeling processes must have liberated calcium to ossify the protective osteodermal structures in juveniles to subadult stages, which led to further remodeling due to increased mechanical loading. Abundant structural fibers observed in the primary bone and even in remodeled bone may have improved the mechanical properties of the Haversian bone.

  5. A Maintainability Prediction Method Considering Environmental Impacts and Cost

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Maintainability prediction is one kind of primary maintainability action. Design deficiency would be found through predicting maintainability parameters under certain conditions. Now a maintainability prediction method that mainly considers maintenance time or maintenance man-hour is a kind of prediction method with a single index. With increasing product complexity and people's environmental consciousness, more attention is paid to environment impacts and maintenance cost or resource consumption in the maintenance process. It is necessary for a maintainability prediction method that can predict maintenance cost and maintenance environmental impacts. A new maintainability prediction method is presented in this paper based on analyzing existing maintainability prediction methods.The method is MABTCE (maintenance activity based timing/costing/environment impact assessment )and can predict maintenance time, maintenance costing and maintenance environmental impacts andthen improve maintainability design with prediction results.

  6. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    Full Text Available BACKGROUND: Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth. MATERIALS AND METHODS: The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant-bone interface was also investigated by push-out tests. RESULTS: The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony

  7. 3D computed tomographic evaluation of secondary alveolar bone grafts in cleft lip and palate patients

    Energy Technology Data Exchange (ETDEWEB)

    Ohkubo, Fumio; Akai, Hidemi; Hosaka, Yoshiaki [Showa Univ., Tokyo (Japan). School of Medicine

    2001-04-01

    Alveolar bone grafting in patients with cleft lip and palate has becomes a routine part of most treatment regimes. This study was undertaken to estimate how much bone needs to be grafted into the cleft cavity and to evaluate the grafted bone using 3-DCT over a period from the early postoperative stage to after one year. Seventy-five patients divided into four groups according to the type of cleft were studied. All patients underwent secondary alveolar bone grafting using particulate cancellous bone from the anterior iliac crest. The bone graft areas were divided into two regions: the extra-cleft region and the intra-cleft region. The weight and the volume of the grafted bone were correlated and the average density was 1.5 g/ml regardless of the cleft type. The bone in the extra-cleft region could be seen in almost all slices of the CT scans, from the lower alveolar process to the piriform aperture. The extra-cleft graft ratio of unilateral and bilateral cleft lip and palate is higher than that of cleft lip and alveolus. The extra-cleft grafting is necessary to restore facial symmetry. The grafted bone was decreased in both height and volume following three months and adequate bone bridging was maintained for one year. We concluded that 3-DCT findings are one of the most valuable methods to evaluate postoperative conditions after alveolar bone grafting. (author)

  8. The effects of replacing collagen fibers with carbon nanotubes on the rate of bone remodeling process.

    Science.gov (United States)

    Jamilpour, Nima; Fereidoon, Abdolhosein; Rouhi, Gholamreza

    2011-08-01

    Application of carbon nanotubes (CNTs) instead of collagen fibers (CFs) in bone tissue is one of the proposed avenues for the enhancement of bone's mechanical properties. The mechanical behavior improvement caused by such a replacement is somehow guaranteed because of the superior mechanical properties of CNTs compared to those of CFs. But on the other side, bone is a very active and dynamic tissue, which is maintained through a lifelong coupled process of resorption and formation in order to reach an optimal configuration. Hence, the well accepted fact of the bone remodeling dependency on mechanical stimuli besides the differences in mechanical behavior of CNTs and CFs under loading can encourage one to hypothesize that such a replacement would cause an imbalance in the normal rate of bone remodeling process. Results of our finite element analysis indicate that the application of CNTs instead of CFs can cause a significant reduction in strain energy density, assumed here as the mechanical stimulus to initiate the bone remodeling process. Our results also show that this replacement may change the strain energy distribution within the bone. Based on a semi-mechanistic bone remodeling theory, it is speculated that this alteration in strain energy distribution in artificial bone can destabilize normal bone remodeling process, and therefore it is likely to cause some abnormalities in bone's mechanical and biological functions.

  9. Transplantable NK cell progenitors in murine bone marrow.

    Science.gov (United States)

    Moore, T; Bennett, M; Kumar, V

    1995-02-15

    Differentiation of NK cells from pluripotent hematopoietic stem cells is a poorly understood process. Although it is known that NK cells are bone marrow derived and dependent upon an intact bone marrow microenvironment for complete maturation, it is not known if they arise from an intermediate lymphoid stem cell or from progenitors exclusively committed to the NK lineage. To determine whether phenotypically distinct committed NK progenitor cells exist in murine bone marrow, we sorted cells capable of repopulating recipient mice with mature NK cells upon i.v. transfer. We identified a rare population of bone marrow cells with the phenotype Ly6+ Lin- c-kit+ CD43high Fall-3high TSA-1- AA4.1low Rh123high that is highly enriched for the ability to generate NK cells after transplantation. Although these cells are relatively depleted of Rh123low pluripotent stem cells, they are highly enriched for both lymphoid and myeloid repopulating ability. Thus, we have found no evidence to support the existence of a phenotypically distinct transplantable progenitor population in mouse bone marrow that is either exclusively committed to the NK cell lineage or exhibits the functional characteristics of a common lymphoid stem cell.

  10. Mimicking the nanostructure of bone matrix to regenerate bone

    Directory of Open Access Journals (Sweden)

    Robert Kane

    2013-11-01

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

  11. Virtual Temporal Bone Anatomy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Background The Visible Human Project(VHP) initiated by the U.S. National Library of Medicine has drawn much attention and interests from around the world. The Visible Chinese Human (VCH) project has started in China. The current study aims at acquiring a feasible virtual methodology for reconstructing the temporal bone of the Chinese population, which may provide an accurate 3-D model of important temporal bone structures that can be used in teaching and patient care for medical scientists and clinicians. Methods A series of sectional images of the temporal bone were generated from section slices of a female cadaver head. On each sectional image, SOIs (structures of interest) were segmented by carefully defining their contours and filling their areas with certain gray scale values. The processed volume data were then inducted into the 3D Slicer software(developed by the Surgical Planning Lab at Brigham and Women's Hospital and the MIT AI Lab) for resegmentation and generation of a set of tagged images of the SOIs. 3D surface models of SOIs were then reconstructed from these images. Results The temporal bone and structures in the temporal bone, including the tympanic cavity, mastoid cells, sigmoid sinus and internal carotid artery, were successfully reconstructed. The orientation of and spatial relationship among these structures were easily visualized in the reconstructed surface models. Conclusion The 3D Slicer software can be used for 3-dimensional visualization of anatomic structures in the temporal bone, which will greatly facilitate the advance of knowledge and techniques critical for studying and treating disorders involving the temporal bone.

  12. Biodegradable hybrid tissue engineering scaffolds for reconstruction of large bone defects

    Science.gov (United States)

    Barati, Danial

    Complex skeletal injuries and large bone fractures are still a significant clinical problem in US. Approximately 1.5 million Americans (veterans, their families, and civilians) every year suffer from bone loss due to traumatic skeletal injuries, infection, and resection of primary tumors that require extensive grafting to bridge the gap. The US bone graft market is over $2.2 billion a year. Due to insufficient mechanical stability, lack of vascularity, and inadequate resorption of the graft, patients with traumatic large skeletal injuries undergo multiple costly operations followed by extensive recovery steps to maintain proper bone alignment and length. Current strategies for repairing damaged or diseased bones include autologous or allograft bone transplantations. However, limited availability of autografts and risk of disease transmission associated with allografts have necessitated the search for the development of new bone graft options and strategies. The overall goal of this project is to develop a much-needed bone-mimetic engineered graft as a substitute for current strategies providing required bone grafts for reconstruction of large bone defects. This project will use the structure of natural cortical bone as a guide to produce an engineered bone graft with balanced strength, osteogenesis, vascularization, and resorption. The outcome of this project will be a biodegradable hybrid scaffold system (similar to natural cortical bone) including a mechanically strong scaffold allowing for mechanical stability of the load-bearing defect site and a soft and highly porous structure such as a hydrogel phase which will allow for efficient cell and growth factor delivery into the defect implantation site, cell niche establishment and promotion of mineralization. Successful completion of this project will transform bone graft technology for regeneration of complex bone defects from a frozen or freeze-dried allograft to a safe, infection-free, mechanically

  13. The Rho-GEF Kalirin regulates bone mass and the function of osteoblasts and osteoclasts.

    Science.gov (United States)

    Huang, Su; Eleniste, Pierre P; Wayakanon, Kornchanok; Mandela, Prashant; Eipper, Betty A; Mains, Richard E; Allen, Matthew R; Bruzzaniti, Angela

    2014-03-01

    Bone homeostasis is maintained by the balance between bone resorption by osteoclasts and bone formation by osteoblasts. Dysregulation in the activity of the bone cells can lead to osteoporosis, a disease characterized by low bone mass and an increase in bone fragility and risk of fracture. Kalirin is a novel GTP-exchange factor protein that has been shown to play a role in cytoskeletal remodeling and dendritic spine formation in neurons. We examined Kalirin expression in skeletal tissue and found that it was expressed in osteoclasts and osteoblasts. Furthermore, micro-CT analyses of the distal femur of global Kalirin knockout (Kal-KO) mice revealed significantly reduced trabecular and cortical bone parameters in Kal-KO mice, compared to WT mice, with significantly reduced bone mass in 8, 14 and 36week-old female Kal-KO mice. Male mice also exhibited a decrease in bone parameters but not to the level seen in female mice. Histomorphometric analyses also revealed decreased bone formation rate in 14week-old female Kal-KO mice, as well as decreased osteoblast number/bone surface and increased osteoclast surface/bone surface. Consistent with our in vivo findings, the bone resorbing activity and differentiation of Kal-KO osteoclasts was increased in vitro. Although alkaline phosphatase activity by Kal-KO osteoblasts was increased in vitro, Kal-KO osteoblasts showed decreased mineralizing activity, as well as decreased secretion of OPG, which was inversely correlated with ERK activity. Taken together, our findings suggest that deletion of Kalirin directly affects osteoclast and osteoblast activity, leading to decreased OPG secretion by osteoblasts which is likely to alter the RANKL/OPG ratio and promote osteoclastogenesis. Therefore, Kalirin may play a role in paracrine and/or endocrine signaling events that control skeletal bone remodeling and the maintenance of bone mass.

  14. Primary Ewing's sarcoma of the greater wing of the sphenoid bone.

    Science.gov (United States)

    Sharma, R R; Netalkar, A; Lad, S D

    2000-02-01

    Primary Ewing's sarcoma is an uncommon lethal tumour of the long bones and pelvic girdle mainly affecting children and young adults. An origin in the cranial bones is extremely rare. We report a unique case of primary involvement of the greater wing of sphenoid bone in a 16-year-old patient. Aggressive management using microsurgical resection, radiotherapy and chemotherapy was curative. Localized, primary Ewing's sarcoma of the cranial bones should be considered as a distinct clinicopathological entity with an extremely low rate of dural penetration and metastases, and with a relatively better prognosis as compared with those of long bones and pelvic girdle. In neurosurgical practice, primary Ewing's sarcoma of the cranial bones requires early aggressive management to achieve adequate long-term prognosis and cure.

  15. Quantification of bone mineral density to define osteoporosis in rat.

    Science.gov (United States)

    Srivastava, M; Mandal, S K; Sengupta, S; Arshad, M; Singh, M M

    2008-05-01

    The diagnosis of osteoporosis centers on assessment of bone mass and quality. In the absence of evidence-based guidelines to assess bone status in laboratory animals and unsuitability of use of T-/Z-scores meant for clinical application in animal studies, most investigators involved in new drug research and development employ clinical biomarkers and kits to assess bone turnover rate and portray change in bone mineral density (BMD) as percentage of increase/decrease, making comparative assessment of the effect highly impractical. This study proposes threshold boundaries of BMD (rT-score) in colony-bred Sprague-Dawley rats, distinct from those used clinically. Boundaries were obtained keeping fixed Type-I error (alpha=0.025). Femur neck was considered best for defining bone status using BMD measured by dual-energy X-ray absorptiometry. Findings demonstrate that BMD-1.96 and <-0.80 rT-score as osteopenia. Performance of boundaries to ascertain bone status was examined through simulation under different physiological/ hormonal states viz. estrogen deficiency, ageing, estrus cycle, pregnancy, and lactation. The Area Under the Receiver Operating Characteristic curve of 0.98 obtained using BMD of femur neck, being close to unity, shows excellent ability of the proposed rT-score to effectively identify osteoporosis. Further studies using certain hierarchical measures of bone quality such as histomorphometry, mechanical testing etc. could supplement these findings. Since, unlike humans, most laboratory animals including rats only exhibit osteopenia and do not fracture their bones, the proposed thresholds are intended to serve as categorical tools to define bone quality and not to predict fracture risk.

  16. Inca bones at asterion

    Directory of Open Access Journals (Sweden)

    Prashant E Natekar

    2014-01-01

    Full Text Available Background: Surgical approach towards asterion has to be done with caution as many surgeons are unfamiliar with the anatomical variations. The asterion corresponds to the site of the posterolateral (mastoid fontanelle of the neonatal skull which closes at the end of the first year. Inca bones provide information as markers for various diseases, and can mislead in the diagnosis of fractures. Observation and Results: 150 dry skull bones from the Department of Anatomy at Goa Medical College, India and other neighboring medical colleges by examining the asterion, and its sutural articulations with parietal, temporal and occipital bones and also anatomical variations if any in adults. Discussion: The anatomical landmarks selected must be reliable and above all easy to identify. Bony structures are more suitable than soft tissue or cartilaginous landmarks because of their rigid and reliable location. Presence of these bones provides false impressions of fractures or the fractures may be interpreted for inca bones especially in the region of asterion either radiologically or clinically which may lead to complications during burr hole surgeries.

  17. Research on Maintainability Evaluation Model Based on Fuzzy Theory

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Maintainability influencing attributes are analyzed, their weight and value calculating methods are given, and the maintainability fuzzy evaluation method is proposed based on the relative closeness. According to the maintenance task simulation operated in virtual environment, the maintainability virtual evaluation model is built by analyzing the maintenance task for each replaceable unit of product.At last, a case study is given based upon the main landing gear system of a certain type civil aircraft, and the result indicates that the model is suitable for maintainability qualitative evaluation and can support maintainability concurrent design.

  18. A unified theory of bone healing and nonunion: BHN theory.

    Science.gov (United States)

    Elliott, D S; Newman, K J H; Forward, D P; Hahn, D M; Ollivere, B; Kojima, K; Handley, R; Rossiter, N D; Wixted, J J; Smith, R M; Moran, C G

    2016-07-01

    This article presents a unified clinical theory that links established facts about the physiology of bone and homeostasis, with those involved in the healing of fractures and the development of nonunion. The key to this theory is the concept that the tissue that forms in and around a fracture should be considered a specific functional entity. This 'bone-healing unit' produces a physiological response to its biological and mechanical environment, which leads to the normal healing of bone. This tissue responds to mechanical forces and functions according to Wolff's law, Perren's strain theory and Frost's concept of the "mechanostat". In response to the local mechanical environment, the bone-healing unit normally changes with time, producing different tissues that can tolerate various levels of strain. The normal result is the formation of bone that bridges the fracture - healing by callus. Nonunion occurs when the bone-healing unit fails either due to mechanical or biological problems or a combination of both. In clinical practice, the majority of nonunions are due to mechanical problems with instability, resulting in too much strain at the fracture site. In most nonunions, there is an intact bone-healing unit. We suggest that this maintains its biological potential to heal, but fails to function due to the mechanical conditions. The theory predicts the healing pattern of multifragmentary fractures and the observed morphological characteristics of different nonunions. It suggests that the majority of nonunions will heal if the correct mechanical environment is produced by surgery, without the need for biological adjuncts such as autologous bone graft. Cite this article: Bone Joint J 2016;98-B:884-91.

  19. Experimental Investigations on Microcracks in Vibrational and Conventional Drilling of Cortical Bone

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2013-01-01

    Full Text Available Bone drilling is widely used in orthopedic surgery. Microcracks will be generated in bone drilling, which may cause fatigue damages and stress fractures. Fresh bovine cortical bones were drilled via vibrational and conventional ways. Drilling operations were performed by a dynamic material testing machine, which can provide the vibration while maintaining uniform feed motion. The drill site and bone debris were observed through scanning electron microscope (SEM. The experimental results showed that fewer and shorter micro-cracks were formed in vibrational drilling than those formed in conventional way. And the surface morphology of bone debris from two different drilling ways was also quite different. It is expected that vibrational drilling in orthopedic surgery operation could decrease the microdamage to the bone, which could lower the incidence of stress fracture and contribute to the postoperative recovery.

  20. Characterizing microcrack orientation distribution functions in osteonal bone samples.

    Science.gov (United States)

    Wolfram, U; Schwiedrzik, J J; Mirzaali, M J; Bürki, A; Varga, P; Olivier, C; Peyrin, F; Zysset, P K

    2016-12-01

    Prefailure microdamage in bone tissue is considered to be the most detrimental factor in defining its strength and toughness with respect to age and disease. To understand the influence of microcracks on bone mechanics it is necessary to assess their morphology and three-dimensional distribution. This requirement reaches beyond classic histology and stereology, and methods to obtain such information are currently missing. Therefore, the aim of the study was to develop a methodology that allows to characterize three-dimensional microcrack distributions in bulk bone samples. Four dumbbell-shaped specimens of human cortical bone of a 77-year-old female donor were loaded beyond yield in either tension, compression or torsion (one control). Subsequently, synchrotron radiation micro-computed tomography (SRμCT) was used to obtain phase-contrast images of the damaged samples. A microcrack segmentation algorithm was developed and used to segment microcrack families for which microcrack orientation distribution functions were determined. Distinct microcrack families were observed for each load case that resulted in distinct orientation distribution functions. Microcracks had median areas of approximately 4.7 μm(2) , 33.3 μm(2) and 64.0 μm(2) for tension, compression and torsion. Verifying the segmentation algorithm against a manually segmented ground truth showed good results when comparing the microcrack orientation distribution functions. A size dependence was noted when investigating the orientation distribution functions with respect to the size of the volume of interest used for their determination. Furthermore, a scale separation between tensile, compressive and torsional microcracks was noticeable. Visual comparison to classic histology indicated that microcrack families were successfully distinguished. We propose a methodology to analyse three-dimensional microcrack distributions in overloaded cortical bone. Such information could improve our understanding of

  1. Experimental study on healing process of rat mandibular bone fracture examined by radiological procedures

    Energy Technology Data Exchange (ETDEWEB)

    Iuchi, Yukio; Furumoto, Keiichi (Nippon Dental Univ., Tokyo (Japan))

    1994-06-01

    The healing process of rat mandibular fractures was stereoscopically observed daily, using plain roentgenography in the lateral-oblique and tooth axis directions and bone scintigraphy using 99m-Tc-methylene diphosphoric acid (Tc-99m-MDP). The findings were compared with microradiograms of regional polished specimens. X-ray findings included the following. Up to 3 days after bone fracture, the fracture mesiodistally showed distinct radiolucency, with sharp and irregular fracture stump. Radiopacity of the fracture site gradually increased 7 days or later, and bone trabecular formation by callus and stump bridging started to occur at 14 days. Findings similar to those in the control group were observed 49 days or later. The inside was difficult to differentiate, irrespective of the observation time. Bone scans in the mesiodistal and buccolingual planes revealed tracer uptake in the areas of mandibular and soft tissue damage one day after bone fracture. Tracer uptake began to be seen in the fracture site 3 days later, and became marked at 14 days. Then Tc-99m DMP began to be localized and returned to the findings similar to those at 49 days. Bone scanning tended to show wider areas earlier than roentgenography. Microradiographic mesiodistal examination revealed distinct radiopacy of the fracture line for 3 days after bone fracture. Seven days later, bone resorption cavity occurred in the cortical bone around the fracture stump, along with neogenesis of callus. Neogenesis and calcification began to occur gradually, and 14 days later, the fracture osteoremodeling of the internal bone trabeculae was observed. Bone trabecular formation within the bone, however, occurred later. (N.K.).

  2. Bone printing: new frontiers in the treatment of bone defects.

    Science.gov (United States)

    Arealis, Georgios; Nikolaou, Vasileios S

    2015-12-01

    Bone defects can be congenital or acquired resulting from trauma, infection, neoplasm and failed arthroplasty. The osseous reconstruction of these defects is challenging. Unfortunately, none of the current techniques for the repair of bone defects has proven to be fully satisfactory. Bone tissue engineering (BTE) is the field of regenerative medicine (RM) that focuses on alternative treatment options for bone defects that will ideally address all the issues of the traditional techniques in treating large bone defects. However, current techniques of BTE is laborious and have their own shortcomings. More recently, 2D and 3D bone printing has been introduced to overcome most of the limitations of bone grafts and BTE. So far, results are extremely promising, setting new frontiers in the management of bone defects.

  3. STROMAS: A Series of Microgravity Experiments on Bone Forming Cells

    Science.gov (United States)

    Yi, Liu; Massimilano, Monticone; Federico, Tortelli; Matalija, Pujic; Alessandra, Ruggiu; Ranieri, Cancedda

    2008-06-01

    We developed a novel 3D in vitro culture system by seeding cells onto porous bioceramics, mimicking the physiological niche of bone turn-over and enhancing cellular differentiation respective to conventional 2D Petri Dish cultures. Having overcome several technological difficulties, in a series of STROMA spaceflight experiments 3D cultures of bone marrow derived mesenchymal stem cells (BMSC) and co-cultures of osteoblasts and osteoclast precursors were maintained and conserved in automated bioreactors on orbit. Genechip analysis revealed an inhibition of cell proliferation in microgravity. Unexpectedly, genes related to various processes of neural development were significantly upregulated in microgravity, raising the question on the lineage restriction in BMSC.

  4. The distinctive features for standard Chinese (Putonghua)

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jialu

    2006-01-01

    The distinctive features, which are one of the important research subjects in Phonetics and Phonology and in speech technology also, are the ultimate units of speech. Firstly a phoneme system of the standard Chinese-Putonghua was determined based on the results of cluster analysis of perceptual confusion of speech sounds of Putonghua. Then according to the principle of choice between the two opposites proposed by Jakobson, Fant and Halle, considering the characteristics of Putonghua the distinctive feature values for Initials, Finals and Tones were determined in this paper. And the features have been formulated at both acoustic level and genetic level. The distinctive feature trees of Chinese initials and finals were drawn in addition to the feature tables, in order to understand the distinctive features for individual phoneme easily.

  5. Validity of Sensory Systems as Distinct Constructs

    OpenAIRE

    2014-01-01

    Confirmatory factor analysis testing whether sensory questionnaire items represented distinct sensory system constructs found, using data from two age groups, that such constructs can be measured validly using questionnaire data.

  6. Analysis of bone biopsies.

    Science.gov (United States)

    Goodrich, J A; Difiore, R J; Tippens, J K

    1983-11-01

    The orthopedic surgeon is frequently confronted with the decision of when to perform a bone biopsy and whether to do a needle biopsy or an open biopsy. Frequently consultations are received from other services requesting bone biopsies with questionable indications. The indications and contraindications for performing bone biopsies are discussed as well as advantages and disadvantages of either closed or open technique. Four selective cases are discussed with illustrations. The challenge of undiagnosed osseous lesions is best met by rational evaluation of each individual case and coordinated with the team effort of the primary care physician, surgeon, pathologist, and radiologist. The decision for either an open or closed biopsy technique must be based on the experience and skills of the surgeon and pathologist.

  7. Bone healing in 2016

    Science.gov (United States)

    Buza, John A.; Einhorn, Thomas

    2016-01-01

    Summary Delayed fracture healing and nonunion occurs in up to 5–10% of all fractures, and can present a challenging clinical scenario for the treating physician. Methods for the enhancement of skeletal repair may benefit patients that are at risk of, or have experienced, delayed healing or nonunion. These methods can be categorized into either physical stimulation therapies or biological therapies. Physical stimulation therapies include electrical stimulation, low-intensity pulsed ultrasonography, or extracorporeal shock wave therapy. Biological therapies can be further classified into local or systemic therapy based on the method of delivery. Local methods include autologous bone marrow, autologous bone graft, fibroblast growth factor-2, platelet-rich plasma, platelet-derived growth factor, and bone morphogenetic proteins. Systemic therapies include parathyroid hormone and bisphosphonates. This article reviews the current applications and supporting evidence for the use of these therapies in the enhancement of fracture healing. PMID:27920804

  8. Alveolar bone grafting

    Directory of Open Access Journals (Sweden)

    Lilja Jan

    2009-10-01

    Full Text Available In patients with cleft lip and palate, bone grafting in the mixed dentition in the residual alveolar cleft has become a well-established procedure. The main advantages can be summarised as follows: stabilisation of the maxillary arch; facilitation of eruption of the canine and sometimes facilitation of the lateral incisor eruption; providing bony support to the teeth adjacent to the cleft; raising the alar base of the nose; facilitation of closure of an oro-nasal fistula; making it possible to insert a titanium fixture in the grafted site and to obtain favourable periodontal conditions of the teeth within and adjacent to the cleft. The timing of the ABG surgery take into consideration not only eruption of the canine but also that of the lateral incisor, if present. The best time for bone grafting surgery is when a thin shell of bone still covers the soon erupting lateral incisor or canine tooth close to the cleft.

  9. Biochemical markers of bone turnover

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Deog Yoon [College of Medicine, Kyunghee Univ., Seoul (Korea, Republic of)

    1999-08-01

    Biochemical markers of bone turnover has received increasing attention over the past few years, because of the need for sensitivity and specific tool in the clinical investigation of osteoporosis. Bone markers should be unique to bone, reflect changes of bone less, and should be correlated with radiocalcium kinetics, histomorphometry, or changes in bone mass. The markers also should be useful in monitoring treatment efficacy. Although no bone marker has been established to meet all these criteria, currently osteocalcin and pyridinium crosslinks are the most efficient markers to assess the level of bone turnover in the menopausal and senile osteoporosis. Recently, N-terminal telopeptide (NTX), C-terminal telopeptide (CTX) and bone specific alkaline phosphatase are considered as new valid markers of bone turnover. Recent data suggest that CTX and free deoxypyridinoline could predict the subsequent risk of hip fracture of elderly women. Treatment of postmenopausal women with estrogen, calcitonin and bisphosphonates demonstrated rapid decrease of the levels of bone markers that correlated with the long-term increase of bone mass. Factors such as circadian rhythms, diet, age, sex, bone mass and renal function affect the results of biochemical markers and should be appropriately adjusted whenever possible. Each biochemical markers of bone turnover may have its own specific advantages and limitations. Recent advances in research will provide more sensitive and specific assays.

  10. Integrin-specific hydrogels functionalized with VEGF for vascularization and bone regeneration of critical-size bone defects.

    Science.gov (United States)

    García, José R; Clark, Amy Y; García, Andrés J

    2016-04-01

    Vascularization of bone defects is considered a crucial component to the successful regeneration of large bone defects. Although vascular endothelial growth factor (VEGF) has been delivered to critical-size bone defect models to augment blood vessel infiltration into the defect area, its potential to increase bone repair remains ambiguous. In this study, we investigated whether integrin-specific biomaterials modulate the effects of VEGF on bone regeneration. We engineered protease-degradable, VEGF-loaded poly(ethylene glycol) (PEG) hydrogels functionalized with either a triple-helical, α2 β1 integrin-specific peptide GGYGGGP(GPP)5 GFOGER(GPP)5 GPC (GFOGER) or an αv β3 integrin-targeting peptide GRGDSPC (RGD). Covalent incorporation of VEGF into the PEG hydrogel allowed for protease degradation-dependent release of the protein while maintaining VEGF bioactivity. When applied to critical-size segmental defects in the murine radius, GFOGER-functionalized VEGF-free hydrogels exhibited significantly increased vascular volume and density and resulted in a larger number of thicker blood vessels compared to RGD-functionalized VEGF-free hydrogels. VEGF-loaded RGD hydrogels increased vascularization compared to VEGF-free RGD hydrogels, but the levels of vascularization for these VEGF-containing RGD hydrogels were similar to those of VEGF-free GFOGER hydrogels. VEGF transiently increased bone regeneration in RGD hydrogels but had no effect at later time points. In GFOGER hydrogels, VEGF did not show an effect on bone regeneration. However, VEGF-free GFOGER hydrogels resulted in increased bone regeneration compared to VEGF-free RGD hydrogels. These findings demonstrate the importance of integrin-specificity in engineering constructs for vascularization and associated bone regeneration.

  11. Bone pathology inpsoriatic arthritis

    Directory of Open Access Journals (Sweden)

    V. V. Badokin

    2007-01-01

    Full Text Available Objective. To study different variants of osteolysis in pts with psoriatic arthritis (PA and to reveal their relationship with other clinico-radiological features of joint damage. Material and methods. 370 pts with definite PA having different variants of joint damage were included. Radiological examination of bones and joints (in some cases large picture frame was performed. Morphological evaluation of synovial biopsies was done in 34 pts with PA and 10 pts with rheumatoid arthritis (RA. Results. Different types of osteolysis were revealed in 80 (21,6% pts. Osteolytic variant of joint damage was present in 29 pts. 33 pts had acral, 48 — intra-articular osteolysis and 16 - true bone atrophy. Frequency and intensity of bone resorption were associated with severity of PA. Acral osteolysis correlated with arthritis of distal interphalangeal joints and onychodystrophy. Intra-articular osteolysis was most often present in distal interphalangeal joints of hands and metacarpophalangeal joints (39,6% and 41,7% respectively. Characteristic feature of PA was combination of prominent resorption with formation of bone ankylosis and periosteal reaction. Ankylosis was present in 33,3% of pts with intra-articular osteolysis and in 60% of pts with combination of different osteolysis variants. Systemic reaction of microcirculation in synovial biopsies was most prominent in osteolytic variant: marked thickening of capillary and venule basal membrane with high level of acid phosphatase, increased capillary and precapillary blood flow with stasis features, vascular lymphocyte and macrophage infiltration, productive vasculitis with annular wall thickening, thrombovasculitis and villi deep layer sclerosis. Conclusion. Different variants of osteolysis show bone involvement in PA. Acral and intra- articular osteolysis association with bone ankylosis and periostitis proves their common pathogenetic entity.

  12. Sex steroids and bone.

    Science.gov (United States)

    Manolagas, S C; Kousteni, S; Jilka, R L

    2002-01-01

    The adult skeleton is periodically remodeled by temporary anatomic structures that comprise juxtaposed osteoclast and osteoblast teams and replace old bone with new. Estrogens and androgens slow the rate of bone remodeling and protect against bone loss. Conversely, loss of estrogen leads to increased rate of remodeling and tilts the balance between bone resorption and formation in favor of the former. Studies from our group during the last 10 years have elucidated that estrogens and androgens decrease the number of remodeling cycles by attenuating the birth rate of osteoclasts and osteoblasts from their respective progenitors. These effects result, in part, from the transcriptional regulation of genes responsible for osteoclastogenesis and mesenchymal cell replication and/or differentiation and are exerted through interactions of the ligand-activated receptors with other transcription factors. However, increased remodeling alone cannot explain why loss of sex steroids tilts the balance of resorption and formation in favor of the former. Estrogens and androgens also exert effects on the lifespan of mature bone cells: pro-apoptotic effects on osteoclasts but anti-apoptotic effects on osteoblasts and osteocytes. These latter effects stem from a heretofore unexpected function of the classical "nuclear" sex steroid receptors outside the nucleus and result from activation of a Src/Shc/extracellular signal-regulated kinase signal transduction pathway probably within preassembled scaffolds called caveolae. Strikingly, estrogen receptor (ER) alpha or beta or the androgen receptor can transmit anti-apoptotic signals with similar efficiency, irrespective of whether the ligand is an estrogen or an androgen. More importantly, these nongenotropic, sex-nonspecific actions are mediated by the ligand-binding domain of the receptor and can be functionally dissociated from transcriptional activity with synthetic ligands. Taken together, these lines of evidence strongly suggest that

  13. Archival bone marrow samples

    DEFF Research Database (Denmark)

    Lund, Bendik; Najmi, Laeya A; Wesolowska-Andersen, Agata;

    2015-01-01

    AB Archival samples represent a significant potential for genetic studies, particularly in severe diseases with risk of lethal outcome, such as in cancer. In this pilot study, we aimed to evaluate the usability of archival bone marrow smears and biopsies for DNA extraction and purification, whole...... with samples stored for 4 to 10 years. Acceptable call rates for SNPs were detected for 7 of 42 archival samples. In conclusion, archival bone marrow samples are suitable for DNA extraction and multiple marker analysis, but WGA was less successful, especially when longer fragments were analyzed. Multiple SNP...

  14. Computerized geometric features of carpal bone for bone age estimation

    Institute of Scientific and Technical Information of China (English)

    Chi-Wen Hsieh; Tai-Lang Jong; Yi-Hong Chou; Chui-Mei Tiu

    2007-01-01

    Background Bone age development is one of the significant indicators depicting the growth status of children.However, bone age assessment is an heuristic and tedious work for pediatricians. We developed a computerized bone age estimation system based on the analysis of geometric features of carpal bones.Methods The geometric features of carpals were extracted and analyzed to judge the bone age of children by computerized shape and area description. Four classifiers, linear, nearest neighbor, back-propagation neural network,and radial basis function neural network, were adopted to categorize bone age. Principal component and discriminate analyses were employed to improve assorting accuracy.Results The hand X-ray films of 465 boys and 444 girls served as our database. The features were extracted from carpal bone images, including shape, area, and sequence. The proposed normalization area ratio method was effective in bone age classification by simulation. Besides, features statistics showed similar results between the standard of the Greulich and Pyle atlas and our database.Conclusions The bone area has a higher discriminating power to judge bone age. The ossification sequence of trapezium and trapezoid bones between Taiwanese and the atlas of the GP method is quite different. These results also indicate that carpal bone assessment with classification of neural networks can be correct and practical.

  15. Buccal cortical bone thickness on CBCT for mini-implant

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Jong Gook; Lim, Sung Hoon; Lee, Byoung Jin; Kim, Jae Duk [School of Dentistry, Chosun University, Gwangju (Korea, Republic of)

    2010-12-15

    Cortical bone thickness is one of the important factor in mini-implant stability. This study was performed to investigate the buccal cortical bone thickness at every interdental area as an aid in planning mini-implant placement. Two-dimensional slices at every interdental area were selected from the cone-beam computed tomography scans of 20 patients in third decade. Buccal cortical bone thickness was measured at 2, 4, and 6 mm levels from the alveolar crest in the interdental bones of posterior regions of both jaws using the plot profile function of Ez3D2009TM (Vatech, Yongin, Korea). The results were analyzed using by Mann-Whitney test. Buccal cortical bone was thicker in the mandible than in the maxilla. The thickness increased with further distance from the alveolar crest in the maxilla and with coming from the posterior to anterior region in the mandible (p?0.01). The maximum CT value showed an increasing tendency with further distance from the alveolar crest and with coming from posterior to anterior region in both jaws. Interdental buccal cortical bone thickness varied in both jaws, however our study showed a distinct tendency. We expect that these results could be helpful for the selection and preparation of mini-implant sites.

  16. Vitamin D, Calcium, and Bone Health

    Science.gov (United States)

    ... in Balance › Vitamin D, Calcium, and Bone Health Vitamin D, Calcium, and Bone Health March 2012 Download ... also helps keep your bones strong. Why are vitamin D and calcium important to bone health? Vitamin ...

  17. Corporation as Civil Organization in a CSR Campaign: The Challenge of Maintaining Credibility

    DEFF Research Database (Denmark)

    Trapp, Leila

    2011-01-01

    , governments and civil society (Van Marrewijk, 2003). Within this framework, the case study contributes to our understanding of the motivation for the increasing number of CSR partnerships between business and Non-Governmental Organizations (NGOs) (Googins & Rochlin, 2000). More specifically, the analysis...... reveals that if a corporate CSR campaign fosters and enacts a blurring, or even elimination, of sector boundaries to reach campaign aims, important inherent distinctions between business, government, and civil organizations ultimately remain salient to the public. Unless these sector distinctions...... are recognized and maintained in CSR campaigns, challenges to a company’s credibility and reputation can arise. Key words: corporate social responsibility, corporate communication, cross-sector partnerships, corporate sustainability, campaigns, collaboration Paper type: case study Googins, B. K., Rochlin, S. A...

  18. Exercise, lifestyle, and your bones

    Science.gov (United States)

    Osteoporosis - exercise; Low bone density - exercise; Osteopenia - exercise ... your bones strong and lower your risk of osteoporosis and fractures as you get older. Before you begin an exercise program, talk with your health care provider if: ...

  19. Eldercare at Home: Bone Weakness

    Science.gov (United States)

    ... of the hormones that keep bones strong. Without estrogen, bones may become softer, weaker, and more likely to ... should take progesterone (another hormone) as well as estrogen to protect against this. However, recent studies have shown that ...

  20. Marijuana May Blunt Bone Health

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_161575.html Marijuana May Blunt Bone Health Study finds heavy users ... 19, 2016 WEDNESDAY, Oct. 19, 2016 (HealthDay News) -- Marijuana may be bad to the bone, a new ...

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... little information about muscles, tendons or joints. An MRI may be more useful in identifying bone and ... bones and the spinal cord can be evaluated). MRI can also detect subtle or occult fractures or ...

  2. Blood and Bone Marrow Donation

    Science.gov (United States)

    ... waiting for a stem cell transplant. Bone marrow donation The most serious risk associated with donating bone ... you feel fully recovered. Peripheral blood stem cell donation The risks of this type of stem cell ...

  3. Vitamin A and Bone Health

    Science.gov (United States)

    ... supported by your browser. Home Bone Basics Nutrition Vitamin A and Bone Health Publication available in: PDF ( ... Find More Information? For Your Information What Is Vitamin A? Vitamin A is a family of compounds ...

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... produce pictures of any bone in the body. It is commonly used to diagnose fractured bones or ... pass through most objects, including the body. Once it is carefully aimed at the part of the ...

  5. Nanomaterials promise better bone repair

    Directory of Open Access Journals (Sweden)

    Qifei Wang

    2016-10-01

    Full Text Available Nanomaterials mimicking the nano-features of bones and offering unique smart functions are promising for better bone fracture repair. This review provides an overview of the current state-of-the-art research in developing and using nanomaterials for better bone fracture repair. This review begins with a brief introduction of bone fracture repair processes, then discusses the importance of vascularization, the role of growth factors in bone fracture repair, and the failure of bone fracture repair. Next, the review discusses the applications of nanomaterials for bone fracture repair, with a focus on the recent breakthroughs such as nanomaterials leading to precise immobilization of growth factors at the molecular level, promoting vascularization without the use of growth factors, and re-loading therapeutic agents after implantation. The review concludes with perspectives on challenges and future directions for developing nanomaterials for improved bone fracture repair.

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... your doctor to view and assess bone fractures, injuries and joint abnormalities. This exam requires little to ... fusion, joint replacement and fracture reductions. look for injury, infection, arthritis , abnormal bone growths and bony changes ...

  7. Aging, human immunodeficiency virus, and bone health

    Directory of Open Access Journals (Sweden)

    Kim C Mansky

    2010-09-01

    Full Text Available Kim C ManskyDivision of Orthodontics, Department of Developmental and Surgical Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN, USAAbstract: Highly active antiretroviral therapy (HAART has had a profound impact on improving the long-term prognosis for individuals infected with human immunodeficiency virus (HIV. HAART has been available for close to two decades, and now a significant number of patients with access to HAART are over the age of 50 years. Many clinical studies have indicated that HIV infection, as well as components of HAART, can increase the risk in these individuals to a variety of noninfectious complications, including a risk to bone health. There is a significant need for detailed mechanistic analysis of the aging, HIV-infected population regarding the risk of HIV infection and therapy in order to maintain bone health. Insights from basic mechanistic studies will help to shed light on the role of HIV infection and the components of HAART that impact bone health, and will help in identifying preventative countermeasures, particularly for individuals 50 years of age and older.Keywords: osteopenia, osteomalacia, osteoporosis, bisphosphonates, tenofovir, osteoimmunology

  8. Bioceramics: from bone regeneration to cancer nanomedicine.

    Science.gov (United States)

    Vallet-Regí, María; Ruiz-Hernández, Eduardo

    2011-11-23

    Research on biomaterials has been growing in the last few years due to the clinical needs in organs and tissues replacement and regeneration. In addition, cancer nanomedicine has recently appeared as an effective means to combine nanotechnology developments towards a clinical application. Ceramic materials are suitable candidates to be used in the manufacturing of bone-like scaffolds. Bioceramic materials may also be designed to deliver biologically active substances aimed at repairing, maintaining, restoring or improving the function of organs and tissues in the organism. Several materials such as calcium phosphates, glasses and glass ceramics able to load and subsequently release in a controlled fashion drugs, hormones, growth factors, peptides or nucleic acids have been developed. In particular, to prevent post surgical infections bioceramics may be surface modified and loaded with certain antibiotics, thus preventing the formation of bacterial biofilms. Remarkably, mesoporous bioactive glasses have shown excellent characteristics as drug carrying bone regeneration materials. These bioceramics are not only osteoconductive and osteoproductive, but also osteoinductive, and have therefore been proposed as ideal components for the fabrication of scaffolds for bone tissue engineering. A recent promising development of bioceramic materials is related to the design of magnetic mediators against tumors. Magnetic composites are suitable thermoseeds for cancer treatment by hyperthermia. Moreover, magnetic nanomaterials offer a wide range of possibilities for diagnosis and therapy. These nanoparticles may be conjugated with therapeutic agents and heat the surrounding tissue under the action of alternating magnetic fields, enabling hyperthermia of cancer as an effective adjunct to chemotherapy regimens.

  9. Perfusion Method for Intra-bone Marrow Collection and Stem Cell Transplantation: A Critical Review.

    Science.gov (United States)

    Korrapati, Narasimhulu; Nanganuru, Harikrishna Yadav

    2014-03-19

    A bone marrow transplant is a procedure to replace damaged or destroyed bone marrow with healthy bone marrow stem cells. Bone marrow is the soft, fatty tissue inside our bones. Bone marrow transplantation (BMT) is a powerful strategy for the treatment of leukemia, aplastic anemia, congenital immunodeficiency and autoimmune diseases. In humans, bone marrow cells (BMCs) have usually been collected by multiple bone marrow aspirations from the iliac crest. We have established a new "perfusion" method for collecting BMCs with minimal contamination with the peripheral blood using the long bones of cynomolgus monkeys. This method has proven to be a simple and safe method for harvesting BMCs and reduces the risk of acute graft versus host disease in allogeneic BMT. Intra-bone marrow-BMT (IBM-BMT) provides distinct advantages because it recruits donor-derived hematopoietic stem cells and mesenchymal stem cells. IBM-BMT has been shown to currently be the best strategy for allogeneic BMT. Here we review the perfusion method (for harvesting BMCs) and IBM-BMT (for their transplantation) and show that this combination will become a powerful new clinical strategy for allogeneic BMT.

  10. Fractal features of dark, maintained, and driven neural discharges in the cat visual system

    CERN Document Server

    Lowen, S B; Kaplan, E; Saleh, B E A; Teich, M C; Lowen, Steven B.; Ozaki, Tsuyoshi; Kaplan, Ehud; Saleh, Bahaa E. A.; Teich, Malvin C.

    1999-01-01

    We employ a number of statistical measures to characterize neural discharge activity in cat retinal ganglion cells (RGCs) and in their target lateral geniculate nucleus (LGN) neurons under various stimulus conditions, and we develop a new measure to examine correlations in fractal activity between spike-train pairs. In the absence of stimulation (i.e., in the dark), RGC and LGN discharges exhibit similar properties. The presentation of a constant, uniform luminance to the eye reduces the fractal fluctuations in the RGC maintained discharge but enhances them in the target LGN discharge, so that neural activity in the pair no longer mirror each other. A drifting-grating stimulus yields RGC and LGN driven spike trains similar in character to those observed in the maintained discharge, with two notable distinctions: action potentials are reorganized along the time axis so that they occur only during certain phases of the stimulus waveform, and fractal activity is suppressed. Under both uniform-luminance and drift...

  11. Ergothioneine Maintains Redox and Bioenergetic Homeostasis Essential for Drug Susceptibility and Virulence of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Vikram Saini

    2016-01-01

    Full Text Available The mechanisms by which Mycobacterium tuberculosis (Mtb maintains metabolic equilibrium to survive during infection and upon exposure to antimycobacterial drugs are poorly characterized. Ergothioneine (EGT and mycothiol (MSH are the major redox buffers present in Mtb, but the contribution of EGT to Mtb redox homeostasis and virulence remains unknown. We report that Mtb WhiB3, a 4Fe-4S redox sensor protein, regulates EGT production and maintains bioenergetic homeostasis. We show that central carbon metabolism and lipid precursors regulate EGT production and that EGT modulates drug sensitivity. Notably, EGT and MSH are both essential for redox and bioenergetic homeostasis. Transcriptomic analyses of EGT and MSH mutants indicate overlapping but distinct functions of EGT and MSH. Last, we show that EGT is critical for Mtb survival in both macrophages and mice. This study has uncovered a dynamic balance between Mtb redox and bioenergetic homeostasis, which critically influences Mtb drug susceptibility and pathogenicity.

  12. Terrestrial applications of bone and muscle research in microgravity.

    Science.gov (United States)

    Booth, F W

    1994-01-01

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

  13. Terrestrial applications of bone and muscle research in microgravity

    Science.gov (United States)

    Booth, F. W.

    1994-08-01

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

  14. Characterization of Fatty Acid Composition in Bone Marrow Fluid From Postmenopausal Women: Modification After Hip Fracture.

    Science.gov (United States)

    Miranda, Melissa; Pino, Ana María; Fuenzalida, Karen; Rosen, Clifford J; Seitz, Germán; Rodríguez, J Pablo

    2016-10-01

    Bone marrow adipose tissue (BMAT) is associated with low bone mass, although the functional consequences for skeletal maintenance of increased BMAT are currently unclear. BMAT might have a role in systemic energy metabolism, and could be an energy source as well as an endocrine organ for neighboring bone cells, releasing cytokines, adipokines and free fatty acids into the bone marrow microenvironment. The aim of the present report was to compare the fatty acid composition in the bone marrow supernatant fluid (BMSF) and blood plasma of postmenopausal women women (65-80 years old). BMSF was obtained after spinning the aspirated bone marrow samples; donors were classified as control, osteopenic or osteoporotic after dual-energy X-ray absorptiometry. Total lipids from human bone marrow fluid and plasma were extracted, converted to the corresponding methyl esters, and finally analyzed by a gas chromatographer coupled with a mass spectrometer. Results showed that fatty acid composition in BMSF was dynamic and distinct from blood plasma, implying significance in the locally produced lipids. The fatty acid composition in the BMSF was enriched in saturated fatty acid and decreased in unsaturated fatty acids as compared to blood plasma, but this relationship switched in women who suffered a hip fracture. On the other hand, there was no relationship between BMSF and bone mineral density. In conclusion, lipid composition of BMSF is distinct from the circulatory compartment, most likely reflecting the energy needs of the marrow compartment. J. Cell. Biochem. 117: 2370-2376, 2016. © 2016 Wiley Periodicals, Inc.

  15. Birefringence properties of a polarization maintaining Panda fibre during Bragg grating regeneration

    Science.gov (United States)

    Polz, Leonhard; Jarsen, Andreas; Bartelt, Hartmut; Roths, Johannes

    2015-09-01

    Regeneration of fibre Bragg gratings under application of a high temperature annealing process in a high birefringent polarisation maintaining fibre of type Panda was investigated. During the annealing process, a distinct nonlinearity and hysteresis of the birefringence with temperature was observed. After the temperature process, the birefringence between slow and fast axis at room temperature was nearly doubled, which is in agreement with observations of other researchers. The hysteresis in birefringence might be explained by the crossing of the transition temperature of the stress applying parts and the relief of in-frozen mechanical and thermal stresses.

  16. Transcutaneous Raman Spectroscopy of Bone

    Science.gov (United States)

    Maher, Jason R.

    Clinical diagnoses of bone health and fracture risk typically rely upon measurements of bone density or structure, but the strength of a bone is also dependent upon its chemical composition. One technology that has been used extensively in ex vivo, exposed-bone studies to measure the chemical composition of bone is Raman spectroscopy. This spectroscopic technique provides chemical information about a sample by probing its molecular vibrations. In the case of bone tissue, Raman spectra provide chemical information about both the inorganic mineral and organic matrix components, which each contribute to bone strength. To explore the relationship between bone strength and chemical composition, our laboratory has contributed to ex vivo, exposed-bone animal studies of rheumatoid arthritis, glucocorticoid-induced osteoporosis, and prolonged lead exposure. All of these studies suggest that Raman-based predictions of biomechanical strength may be more accurate than those produced by the clinically-used parameter of bone mineral density. The utility of Raman spectroscopy in ex vivo, exposed-bone studies has inspired attempts to perform bone spectroscopy transcutaneously. Although the results are promising, further advancements are necessary to make non-invasive, in vivo measurements of bone that are of sufficient quality to generate accurate predictions of fracture risk. In order to separate the signals from bone and soft tissue that contribute to a transcutaneous measurement, we developed an overconstrained extraction algorithm that is based upon fitting with spectral libraries derived from separately-acquired measurements of the underlying tissue components. This approach allows for accurate spectral unmixing despite the fact that similar chemical components (e.g., type I collagen) are present in both soft tissue and bone and was applied to experimental data in order to transcutaneously detect, to our knowledge for the first time, age- and disease-related spectral

  17. Targeting Bone Metabolism in Patients with Advanced Prostate Cancer: Current Options and Controversies

    Directory of Open Access Journals (Sweden)

    Tilman Todenhöfer

    2015-01-01

    Full Text Available Maintaining bone health remains a clinical challenge in patients with prostate cancer (PC who are at risk of developing metastatic bone disease and increased bone loss due to hormone ablation therapy. In patients with cancer-treatment induced bone loss (CTIBL, antiresorptive agents have been shown to improve bone mineral density (BMD and to reduce the risk of fractures. For patients with bone metastases, both zoledronic acid and denosumab delay skeletal related events (SREs in the castration resistant stage of disease. Novel agents targeting the Wnt inhibitors dickkopf-1 and sclerostin are currently under investigation for the treatment of osteoporosis and malignant bone disease. New antineoplastic drugs such as abiraterone, enzalutamide, and Radium-223 are capable of further delaying SREs in patients with advanced PC. The benefit of antiresorptive treatment for patients with castration sensitive PC appears to be limited. Recent trials on the use of zoledronic acid for the prevention of bone metastases failed to be successful, whereas denosumab delayed the occurrence of bone metastases by a median of 4.1 months. Currently, the use of antiresorptive drugs to prevent bone metastases still remains a field of controversies and further trials are needed to identify patient subgroups that may profit from early therapy.

  18. Modalities for Visualization of Cortical Bone Remodeling: The Past, Present, and Future.

    Science.gov (United States)

    Harrison, Kimberly D; Cooper, David M L

    2015-01-01

    Bone's ability to respond to load-related phenomena and repair microdamage is achieved through the remodeling process, which renews bone by activating groups of cells known as basic multicellular units (BMUs). The products of BMUs, secondary osteons, have been extensively studied via classic two-dimensional techniques, which have provided a wealth of information on how histomorphology relates to skeletal structure and function. Remodeling is critical in maintaining healthy bone tissue; however, in osteoporotic bone, imbalanced resorption results in increased bone fragility and fracture. With increasing life expectancy, such degenerative bone diseases are a growing concern. The three-dimensional (3D) morphology of BMUs and their correlation to function, however, are not well-characterized and little is known about the specific mechanisms that initiate and regulate their activity within cortical bone. We believe a key limitation has been the lack of 3D information about BMU morphology and activity. Thus, this paper reviews methodologies for 3D investigation of cortical bone remodeling and, specifically, structures associated with BMU activity (resorption spaces) and the structures they create (secondary osteons), spanning from histology to modern ex vivo imaging modalities, culminating with the growing potential of in vivo imaging. This collection of papers focuses on the theme of "putting the 'why' back into bone architecture." Remodeling is one of two mechanisms "how" bone structure is dynamically modified and thus an improved 3D understanding of this fundamental process is crucial to ultimately understanding the "why."

  19. Accelerated growth plate mineralization and foreshortened proximal limb bones in fetuin-A knockout mice.

    Science.gov (United States)

    Seto, Jong; Busse, Björn; Gupta, Himadri S; Schäfer, Cora; Krauss, Stefanie; Dunlop, John W C; Masic, Admir; Kerschnitzki, Michael; Zaslansky, Paul; Boesecke, Peter; Catalá-Lehnen, Philip; Schinke, Thorsten; Fratzl, Peter; Jahnen-Dechent, Willi

    2012-01-01

    The plasma protein fetuin-A/alpha2-HS-glycoprotein (genetic symbol Ahsg) is a systemic inhibitor of extraskeletal mineralization, which is best underscored by the excessive mineral deposition found in various tissues of fetuin-A deficient mice on the calcification-prone genetic background DBA/2. Fetuin-A is known to accumulate in the bone matrix thus an effect of fetuin-A on skeletal mineralization is expected. We examined the bones of fetuin-A deficient mice maintained on a C57BL/6 genetic background to avoid bone disease secondary to renal calcification. Here, we show that fetuin-A deficient mice display normal trabecular bone mass in the spine, but increased cortical thickness in the femur. Bone material properties, as well as mineral and collagen characteristics of cortical bone were unaffected by the absence of fetuin-A. In contrast, the long bones especially proximal limb bones were severely stunted in fetuin-A deficient mice compared to wildtype littermates, resulting in increased biomechanical stability of fetuin-A deficient femora in three-point-bending tests. Elevated backscattered electron signal intensities reflected an increased mineral content in the growth plates of fetuin-A deficient long bones, corroborating its physiological role as an inhibitor of excessive mineralization in the growth plate cartilage matrix--a site of vigorous physiological mineralization. We show that in the case of fetuin-A deficiency, active mineralization inhibition is a necessity for proper long bone growth.

  20. Playing with bone and fat

    DEFF Research Database (Denmark)

    Gimble, Jeffrey M.; Zvonic, Sanjin; Floyd, Z. Elisabeth

    2006-01-01

    The relationship between bone and fat formation within the bone marrow microenvironment is complex and remains an area of active investigation. Classical in vitro and in vivo studies strongly support an inverse relationship between the commitment of bone marrow-derived mesenchymal stem cells...

  1. Gout: Value of bone scanning

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, J.P.; Cardenas, R.; Bell, L.; Gonzalez Griego, J.

    1986-12-01

    11 male patients with gout were studied by means of bone scintigraphy with /sup 99m/TcMDP. This diagnostic method rendered possible the diagnosis of clinically or roentgenologically occult bone involvement. Bone scintigraphy may be useful procedure to monitor therapy of gout.

  2. Bone regeneration during distraction osteogenesis

    NARCIS (Netherlands)

    Amir, L.R.; Everts, V.; Bronckers, A.L.J.J.

    2009-01-01

    Bone has the capacity to regenerate in response to injury. During distraction osteogenesis, the renewal of bone is enhanced by gradual stretching of the soft connec- tive tissues in the gap area between two separated bone segments. This procedure has received much clinical atten- tion as a way to co

  3. Healthy Bones at Every Age

    Science.gov (United States)

    .org Healthy Bones at Every Age Page ( 1 ) Bone health is important at every age and stage of life. The skeleton is our body’s storage bank for ... are many things we can do at every age to keep our bones strong and healthy. Peak ...

  4. Breast Cancer and Bone Loss

    Science.gov (United States)

    ... Balance › Breast Cancer and Bone Loss Fact Sheet Breast Cancer and Bone Loss July, 2010 Download PDFs English ... JoAnn Pinkerton, MD What is the link between breast cancer and bone loss? Certain treatments for breast cancer ...

  5. Insulin Influences Autophagy Response Distinctively in Macrophages of Different Compartments

    Directory of Open Access Journals (Sweden)

    Karen K. S. Sunahara

    2014-11-01

    Full Text Available Background/Aims: Diabetes mellitus (DM is characterized by hyperglycemia, associated to a lack or inefficiency of the insulin to regulate glucose metabolism. DM is also marked by alterations in a diversity of cellular processes that need to be further unraveled. In this study, we examined the autophagy pathway in diabetic rat macrophages before and after treatment with insulin. Methods: Bone marrow-derived macrophages (BMM, bronchoalveolar lavage (BAL and splenic tissue of diabetic male Wistar rats (alloxan, 42 mg/kg, i.v., 10 days and control rats (physiological saline, i.v.. Some diabetic rats were given neutral protamine Hagedorn insulin (4 IU, s.c. 8 h before experiments. For characterization of the model and evaluation of the effect of insulin on the autophagic process, the following analyzes were performed: (a concentrations of cytokines: interleukin (IL-1β, tumor necrosis factor (TNF-α, IL-6, IL-4, IL-10, cytokine-induced neutrophil chemoattractant (CINC-1 and CINC-2 in the BAL supernatant was measured by ELISA; (b characterization of alveolar macrophage (AM of the BAL as surface antigens (MHCII, pan-macrophage KiM2R, CD11b and autophagic markers (protein microtubule-associated light chain (LC3, autophagy protein (Atg12 by flow cytometry and confocal microscopy (c study of macrophages differentiated from the bone marrow by flow cytometry and confocal microscopy (d histology of the spleen by immunohistochemistry associated with confocal microscopy. Results: Interestingly, insulin exerted antagonistic effects on macrophages from different tissues. Macrophages from bronchoalveolar lavage (BAL enhanced their LC3 autophagosome bound content after treatment with insulin whereas splenic macrophages from red pulp in diabetic rats failed to enhance their Atg 12 levels compared to control animals. Insulin treatment in diabetic rats did not change LC3 content in bone marrow derived macrophages (BMM. M1 and M2 macrophages behaved accordingly to the

  6. Bone vascularization: a way to study bone microarchitecture?

    Science.gov (United States)

    Blery, P.; Autrusseau, F.; Crauste, E.; Freuchet, Erwan; Weiss, Pierre; Guédon, J.-P.; Amouriq, Y.

    2014-03-01

    Trabecular bone and its microarchitecture are of prime importance for health. Studying vascularization helps to better know the relationship between bone and vascular microarchitecture. This research is an animal study (nine Lewis rats), based on the perfusion of vascularization by a contrast agent (a mixture of 50% barium sulfate with 1.5% of gelatin) before euthanasia. The samples were studied by micro CT at a resolution of 9μm. Softwares were used to show 3D volumes of bone and vessels, to calculate bone and vessels microarchitecture parameters. This study aims to understand simultaneously the bone microarchitecture and its vascular microarchitecture.

  7. Temporal bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemmerling, Marc [Algemeen Ziekenhuis Sint-Lucas, Gent (Belgium). Dept. of Radiology; Foer, Bert de (ed.) [Sint-Augustinus Ziekenhuis, Wilrijk (Belgium). Dept. of Radiology

    2015-04-01

    Complete overview of imaging of normal and diseased temporal bone. Straightforward structure to facilitate learning. Detailed consideration of newer imaging techniques, including the hot topic of diffusion-weighted imaging. Includes a chapter on anatomy that will be of great help to the novice interpreter of imaging findings. Excellent illustrations throughout. This book provides a complete overview of imaging of normal and diseased temporal bone. After description of indications for imaging and the cross-sectional imaging anatomy of the area, subsequent chapters address the various diseases and conditions that affect the temporal bone and are likely to be encountered regularly in clinical practice. The classic imaging methods are described and discussed in detail, and individual chapters are included on newer techniques such as functional imaging and diffusion-weighted imaging. There is also a strong focus on postoperative imaging. Throughout, imaging findings are documented with the aid of numerous informative, high-quality illustrations. Temporal Bone Imaging, with its straightforward structure based essentially on topography, will prove of immense value in daily practice.

  8. Bone scintigraphy in psoriasis

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, K.; Thiers, G.; Eissner, D.; Holzmann, H.

    1980-08-01

    Since 1973 bone scintigraphy using sup(99m)Tc-phosphate-complexes was carried out in 382 patients with psoriasis. For comparison with the results of nuclear medicine, roentgenologic and clinical findings a group af 121 patients with psoriasis aged between 11 and 74 years was compared to a group of 42 patients aged between 20 and 49 years without roentgenologic and clinical signs of psoriasis arthritis. We found by means of isotope investigation that an essentially greater part of the bones adjacent to the joints was involved than was expected according to X-ray and clinical findings. In addition, in 205 patients with psoriasis whole-body scintigraphy, using sup(99m)Tc-MDP, was carried out since 1977/78. In 17 patients we found an increased accumulation of activity in the region of extraarticular structures of the skull as well as of the skeletal thorax. According to these results we conclude that in addition to the clinically and roentgenologically defined psoriatic arthritis in patients with psoriasis an osteopathy may exist, which can only be demonstrated by skeletal scintigraphy and which is localized in bones adjacent to the joints but can also be demonstrated in the region of extraarticular bones.

  9. Bone scintigraphy in chondroblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Humphry, A.; Gilday, D.L.; Brown, R.G.

    1980-11-01

    Scintigraphy in 3 patients with chondroblastoma showed that the tumors were hyperemic and avidly accumulated the radionuclide. These changes were also present in adjacent normal bone, but to a lesser degree. This suggests that radionuclide uptake in chondroblastoma is a function of the blood supply to the tumor rather than primary matrix extraction.

  10. Chondroblastoma of temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Tanohta, K.; Noda, M.; Katoh, H.; Okazaki, A.; Sugiyama, S.; Maehara, T.; Onishi, S.; Tanida, T.

    1986-07-01

    The case of a 55-year-old female with chondroblastoma arising from the left temporal bone is presented. Although 10 cases of temporal chondroblastoma have been reported, this is the first in which plain radiography, pluridirectional tomography, computed tomography (CT) and angiography were performed. We discuss the clinical and radiological aspects of this rare tumor.

  11. Performing a bone gammagraphy

    Directory of Open Access Journals (Sweden)

    Marta Corbacho Martín

    2010-03-01

    Full Text Available In the Nuclear Medicine service multitude of diagnostic tests are performed, being one of them the bone gammagraphy that acquires a very important role both by the high demand for this test, because of its simplicity and in the realization by its high sensitivity.The bone gammagraphy as opposed to conventional radiological techniques not only provides an anatomical view, but also adds a functional imaging that provides information on bone metabolism. Addition is not restricted to malignant bone disease (primary or metastatic tumors, but it is very useful for most benign osteoarticular processes. It would be interesting to bring to the nursing knowledge of this test for a proper implementation of it, because it is a very defendant but unknown to many nurses, thus going to unify the standards of performance. The need for nursing professionals during the performance of this technique because the patient remains in these units for quite some time, being responsible for the care while they remain in the unit, taking their physical, psychological and social. We also have a key role in providing information and reassurance when the patient arrives at the unit and it is therefore necessary to have information and training necessary to answer these key questions.

  12. Sodium and bone health

    DEFF Research Database (Denmark)

    Teucher, B.; Dainty, J. R.; Spinks, C. A.

    2008-01-01

    High salt intake is a well-recognized risk factor for osteoporosis because it induces calciuria, but the effects of salt on calcium metabolism and the potential impact on bone health in postmenopausal women have not been fully characterized. This study investigated adaptive mechanisms in response...... was negative on both high and low salt diets....

  13. Food and Your Bones

    Science.gov (United States)

    ... Store Shopping Cart Home › Patients › Treatment › Nutrition Nutrition Food For Thought Quiz Please share why you eat ... never tried prunes View Answers Loading ... Sponsored by: Food and Your Bones – Osteoporosis Nutrition Guidelines The food ...

  14. Bone island and leprosy

    Energy Technology Data Exchange (ETDEWEB)

    Carpintero, P.; Garcia-Frasquet, A. [Department of Orthopaedic Surgery, Cordoba University, Medical School, Reina Sofia University Hospital, Cordoba (Spain); Tarradas, E. [Department of Imaging, Cordoba University, Medical School, Cordoba (Spain); Logrono, C. [Department of Dermatology, Reina Sofia University Hospital, Cordoba (Spain); Carrascal, A. [Department of Radiology, Infanta Elena Hospital, Huelva (Spain); Carreto, A. [Department of Radiology, Reina Sofia University Hospital, Cordoba (Spain)

    1998-06-01

    Objective. To determine the incidence of bone islands in leprosy patients. Design. X-rays of feet and hands of patients with Hansen`s disease (leprosy) were reviewed retrospectively. A second group of related age- and sex-matched patients who did not have Hansen`s disease was used for control purposes. Controls had undergone hand or foot X-rays during diagnosis of other pathologies. The patients with Hansen`s disease were compared with the control group, and were also analyzed as subgroups with different types of leprosy. The results were subjected to statistical analysis. Patients. Ninety patients with Hansen`s disease were randomly selected for this study. Patients who had had ulcers on hands or feet were excluded from the study. Results and conclusions. Bone islands were demonstrated in 20 patients with Hansen`s disease; no bone islands were observed in the controls. This was statistically significant (P<0.01). Bone islands were only seen in patients with lepromatous leprosy and borderline types but were not demonstrated in patients with tuberculoid leprosy. There was also a statistically significant relationship for a disease duration of 15 years or more. The cause of this raised incidence of enostosis in leprosy patients is not clear, but there may be a genetic predisposition in patients with leprosy, or it may be a side effect of leprosy, especially the lepromatous form. (orig.) With 4 figs., 2 tabs., 9 refs.

  15. Bone Marrow Matters

    Science.gov (United States)

    Dunne, Mark; Maklad, Rania; Heaney, Emma

    2014-01-01

    As a final-year student teacher specialising in primary science, Emma Heaney faced the challenge of having to plan, organise, and conduct a small-scale, classroom-based research project. She had to teach about bones in the final block practice session and thought it would be a good idea to bring in some biological specimens obtained from the local…

  16. Bones of the Earth

    Science.gov (United States)

    Correa, Jose Miguel

    2014-01-01

    The film "Bones of the Earth" (Riglin, Cunninham & Correa, 2014) is an experience in collective inquiry and visual creation based on arts-based research. Starting from the meeting of different subjectivities and through dialogue, planning, shooting and editing, an audiovisual text that reconstructs a reflexive process of collective…

  17. Are Bones Alive?

    Science.gov (United States)

    Caravita, Silvia; Falchetti, Elisabetta

    2005-01-01

    Many studies have investigated the classification of living things. Our study deals with a different problem: the attribution of life to one component of a living organism, specifically the bones. The task involves not only specifying what we mean by "alive", but also requires "informed thinking" leading to an understanding of…

  18. Surgery for Bone Cancer

    Science.gov (United States)

    ... be amputated mid-thigh, the lower leg and foot can be rotated and attached to the thigh bone. The old ankle joint becomes the new knee joint. This surgery is called rotationplasty (roh-TAY-shun-PLAS-tee). A prosthesis is used to make the new leg the ...

  19. Should we maintain baby hatches in our society?

    Directory of Open Access Journals (Sweden)

    Asai Atsushi

    2013-02-01

    Full Text Available Abstract Background A baby hatch called the “Stork’s Cradle” has been in place at Jikei Hospital in Kumamoto City, Japan, since May 10, 2007. Babyklappes were first established in Germany in 2000, and there are currently more than 90 locations. Attitudes regarding baby hatches are divided in Japan and neither opinions for nor against baby hatches have thus far been overwhelming. To consider the appropriateness of baby hatches, we present and examine the validity of each major objection to establishing baby hatches. Discussion There are various objections to baby hatches as follows: It violates a child’s right to know the identity of his or her biological parents by allowing anonymous birth; it neglects fulfillment of the biological parents’ basic obligation to raise their child and its very availability induces abandonment of infants; some people abuse it for very selfish reasons; it cannot save babies’ lives; the rights of one parent can be ignored if the other surrenders a child without his or her consent; it puts a baby in medical jeopardy; and it has no clear legal basis. The authors would argue that there are many plausible refutations for each objection mainly based on priority of child’s right to life, pregnant women’s vulnerability and necessity of anonymity, social responsibility to protect and raise children, differences between dropping a child off at a baby hatch and child neglect, limited function of social childcare center, inevitability of abuse by a minority of people, necessary distinction between outcomes that occur only because baby hatches exist and those that occur regardless of their existence, important local direct and upmost measures for women in trouble, and difference between ambiguous legality and illegality. Summary We argue that a certain number of baby hatches should continue to be established as a last resort, in a form that can maintain anonymity if the parent dropping the child off so desires. It

  20. A novel role of IL-17–producing lymphocytes in mediating lytic bone disease in multiple myeloma

    Science.gov (United States)

    Noonan, Kimberly; Marchionni, Luigi; Anderson, Judy; Pardoll, Drew; Roodman, G. David

    2010-01-01

    Osteoclast (OC)–mediated lytic bone disease remains a cause of major morbidity in multiple myeloma. Here we demonstrate the critical role of interleukin-17–producing marrow infiltrating lymphocytes (MILs) in OC activation and development of bone lesions in myeloma patients. Unlike MILs from normal bone marrow, myeloma MILs possess few regulatory T cells (Tregs) and demonstrate an interleukin-17 phenotype that enhances OC activation. In univariate analyses of factors mediating bone destruction, levels of cytokines that selectively induce and maintain the Th17 phenotype tightly correlated with the extent of bone disease in myeloma. In contrast, MILs activated under conditions that skew toward a Th1 phenotype significantly reduced formation of mature OC. These findings demonstrate that interleukin-17 T cells are critical to the genesis of myeloma bone disease and that immunologic manipulations shifting MILs from a Th17 to a Th1 phenotype may profoundly diminish lytic bone lesions in multiple myeloma. PMID:20664052

  1. Bacillus subtilis chromosome organization oscillates between two distinct patterns.

    Science.gov (United States)

    Wang, Xindan; Montero Llopis, Paula; Rudner, David Z

    2014-09-02

    Bacterial chromosomes have been found to possess one of two distinct patterns of spatial organization. In the first, called "ori-ter" and exemplified by Caulobacter crescentus, the chromosome arms lie side-by-side, with the replication origin and terminus at opposite cell poles. In the second, observed in slow-growing Escherichia coli ("left-ori-right"), the two chromosome arms reside in separate cell halves, on either side of a centrally located origin. These two patterns, rotated 90° relative to each other, appear to result from different segregation mechanisms. Here, we show that the Bacillus subtilis chromosome alternates between them. For most of the cell cycle, newly replicated origins are maintained at opposite poles with chromosome arms adjacent to each other, in an ori-ter configuration. Shortly after replication initiation, the duplicated origins move as a unit to midcell and the two unreplicated arms resolve into opposite cell halves, generating a left-ori-right pattern. The origins are then actively segregated toward opposite poles, resetting the cycle. Our data suggest that the condensin complex and the parABS partitioning system are the principal driving forces underlying this oscillatory cycle. We propose that the distinct organization patterns observed for bacterial chromosomes reflect a common organization-segregation mechanism, and that simple modifications to it underlie the unique patterns observed in different species.

  2. Acute hypothalamic suppression significantly affects trabecular bone but not cortical bone following recovery and ovariectomy surgery in a rat model

    Directory of Open Access Journals (Sweden)

    Vanessa R. Yingling

    2016-01-01

    RH-a group compared to C, a similar deficit in BV/TV was also measured following recovery and post-OVX. The trabecular number and thickness were lower in the GnRH-a group compared to control.Conclusion. These data suggest that following a transient delay in pubertal onset, trabecular bone volume was significantly lower and no restoration of bone volume occurred following recovery or post-OVX surgery. However, cortical bone strength was maintained through architectural adaptations in the cortical bone envelope. An increase in the polar moment of inertia offset increased bone resorption. The current data are the first to suppress trabecular bone during growth, and then add an OVX protocol at maturity. Trabecular bone and cortical bone differed in their response to hypothalamic suppression during development; trabecular bone was more sensitive to the negative effects of hypothalamic suppression.

  3. Distinctiveness of Saudi Arabian EFL Learners

    Directory of Open Access Journals (Sweden)

    Manssour Habbash

    2016-04-01

    Full Text Available In view of the increasing concern among English language teachers dealing with students from Saudi Arabia, as it manifests in TESOL community discussions, about the uniqueness of Saudi Arabian EFL learners, this paper attempts to document the outcome of a study of their distinctiveness from the perspective of expatriate teachers working for PYPs (Preparatory Year Programs in Saudi Arabia. This study examines the distinctiveness with regard to the learning attitudes of Saudi students that are often cultivated by the culture and academic environment in their homeland. Employing an emic approach for collecting the required data an analysis was carried out in light of the other studies on ‘education’ in Saudi Arabia that have particular reference to the factors that can positively influence student motivation, student success and the academic environment. The findings were used in constructing the rationale behind such distinctiveness. Assuming that the outcome of the discussion on the findings of this exploration can be helpful for teachers in adapting their teaching methodology and improving their teacher efficacy in dealing with students both from the kingdom and in the kingdom, some recommendations are made. Keywords: China Distinctiveness, Saudi Arabian University context, Expatriate teachers’ perspective, Distinctiveness Theory

  4. Bone marrow oedema associated with benign and malignant bone tumours

    Energy Technology Data Exchange (ETDEWEB)

    James, S.L.J. [Department of Radiology, Royal Orthopaedic Hospital, Birmingham, B31 2AP (United Kingdom)], E-mail: steven.james@roh.nhs.uk; Panicek, D.M. [Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 (United States); Davies, A.M. [Department of Radiology, Royal Orthopaedic Hospital, Birmingham, B31 2AP (United Kingdom)

    2008-07-15

    Bone marrow oedema is associated with a wide variety of pathological processes including both benign and malignant bone tumours. This imaging finding in relation to intraosseous tumours can aid in providing a more focused differential diagnosis. In this review, we will discuss the MR imaging of bone marrow oedema surrounding intraosseous neoplasms. The different pulse sequences used in differentiating underlying tumour from surrounding oedema are discussed along with the role of dynamic contrast enhanced MRI. Benign lesions commonly associated with bone marrow oedema include osteoid osteoma, osteoblastoma, chondroblastoma and Langerhan's cell histiocytosis. Metastases and malignant primary bone tumours such as osteosarcoma, Ewing's sarcoma and chondrosarcoma may also be surrounded by bone marrow oedema. The imaging findings of these conditions are reviewed and illustrated. Finally, the importance of bone marrow oedema in assessment of post chemotherapeutic response is addressed.

  5. Evolutionary patterns of bone histology and bone compactness in xenarthran mammal long bones.

    Science.gov (United States)

    Straehl, Fiona R; Scheyer, Torsten M; Forasiepi, Analía M; MacPhee, Ross D; Sánchez-Villagra, Marcelo R

    2013-01-01

    Bone microstructure reflects physiological characteristics and has been shown to contain phylogenetic and ecological signals. Although mammalian long bone histology is receiving increasing attention, systematic examination of the main clades has not yet been performed. Here we describe the long bone microstructure of Xenarthra based on thin sections representing twenty-two species. Additionally, patterns in bone compactness of humeri and femora are investigated. The primary bone tissue of xenarthran long bones is composed of a mixture of woven, parallel-fibered and lamellar bone. The vascular canals have a longitudinal, reticular or radial orientation and are mostly arranged in an irregular manner. Concentric rows of vascular canals and laminar organization of the tissue are only found in anteater bones. The long bones of adult specimens are marked by dense Haversian bone, a feature that has been noted for most groups of mammals. In the long bones of armadillos, secondary osteons have an oblique orientation within the three-dimensional bone tissue, thus resulting in their irregular shape when the bones are sectioned transversely. Secondary remodeling is generally more extensive in large taxa than in small taxa, and this could be caused by increased loading. Lines of arrested growth are assumed to be present in all specimens, but they are restricted to the outermost layer in bones of armadillos and are often masked by secondary remodeling in large taxa. Parameters of bone compactness show a pattern in the femur that separates Cingulata and Pilosa (Folivora and Vermilingua), with cingulates having a lower compactness than pilosans. In addition, cingulates show an allometric relationship between humeral and femoral bone compactness.

  6. Moral fiction or moral fact? The distinction between doing and allowing in medical ethics.

    Science.gov (United States)

    Huddle, Thomas S

    2013-06-01

    Opponents of physician-assisted suicide (PAS) maintain that physician withdrawal-of-life-sustaining-treatment cannot be morally equated to voluntary active euthanasia. PAS opponents generally distinguish these two kinds of act by positing a possible moral distinction between killing and allowing-to-die, ceteris paribus. While that distinction continues to be widely accepted in the public discourse, it has been more controversial among philosophers. Some ethicist PAS advocates are so certain that the distinction is invalid that they describe PAS opponents who hold to the distinction as in the grip of 'moral fictions'. The author contends that such a diagnosis is too hasty. The possibility of a moral distinction between active euthanasia and allowing-to-die has not been closed off by the argumentative strategies employed by these PAS advocates, including the contrasting cases strategy and the assimilation of doing and allowing to a common sense notion of causation. The philosophical debate over the doing/allowing distinction remains inconclusive, but physicians and others who rely upon that distinction in thinking about the ethics of end-of-life care need not give up on it in response to these arguments.

  7. Nuclear microprobe analysis of lead profile in crocodile bones

    Science.gov (United States)

    Orlic, I.; Siegele, R.; Hammerton, K.; Jeffree, R. A.; Cohen, D. D.

    2003-09-01

    Elevated concentrations of lead were found in Australian free ranging saltwater crocodile ( Crocodylus porosus) bone and flesh. Lead shots were found as potential source of lead in these animals. ANSTO's heavy ion nuclear microprobe was used to measure the distribution of Pb in a number of bones and osteoderms. The aim was to find out if elevated Pb concentration remains in growth rings and if the concentration is correlated with the blood levels recorded at the time. Results of our study show a very distinct distribution of accumulated Pb in bones and osteoderms as well as good correlation with the level of lead concentration in blood. To investigate influence of ion species on detection limits measurements of the same sample were performed by using 3 MeV protons, 9 MeV He ions and 20 MeV carbon ions. Peak to background ratios, detection limits and the overall 'quality' of obtained spectra are compared and discussed.

  8. Bone Loss During Spaceflight: Available Models and Counter-Measures

    Science.gov (United States)

    Morris, Jonathan; Bach, David; Geller, David

    2015-01-01

    There is ongoing concern for human health during spaceflights. Of particular interest is the uncoupling of bone remodeling and its resultant effect on calcium metabolism and bone loss. The calculated average loss of bone mineral density (BMD) is approximately 1-1.5% per month of spaceflight. The effect of decreased BMD on associated fractures in astronauts is not known. Currently on the International Space Station (ISS), bone loss is managed through dietary supplements and modifications and resistance exercise regimen. As the duration of space flights increases, a review of the current methods available for the prevention of bone loss is warranted. The goal of this project is to review and summarize recent studies that have focused on maintaining BMD during exposure to microgravity. Interventions were divided into physical (Table 1), nutritional (Table 2), or pharmacologic (Table 3) categories. Physical modalities included resistance exercise, low level vibration, and low intensity pulsed ultrasound. Nutritional interventions included altering protein, salt, and fat intake; and vitamin D supplementation. Pharmacologic interventions included the use of bisphosphonates and beta blockers. Studies reported outcomes based on bone density determined by DXA bone scan, micro-architecture of histology and microCT, and serum and urine markers of bone turnover. The ground analog models utilized to approximate osseous physiology in microgravity included human patients previously paralyzed or subjects confined to bedrest. Ground analog animal models include paralysis, immobilization and ovariectomies. As a result of the extensive research performed there is a multi-modality approach available for the management of BMD during spaceflight that includes resistance training, nutrition and dietary supplements. However, there is a paucity of literature describing a formalized tiered protocol to guide investigators through the progression from animal models to human patient ground

  9. On Hobbes’s distinction of accidents

    Directory of Open Access Journals (Sweden)

    Lupoli Agostino

    2012-06-01

    Full Text Available An interpolation introduced by K. Schuhmann in his critical edition of "De corpore" (chap. VI, § 13 diametrically overturns the meaning of Hobbes’s doctrine of distinction of accidents in comparison with all previous editions. The article focuses on the complexity of this crucial juncture in "De corpore" argument on which depends the interpretation of Hobbes’s whole conception of science. It discusses the reasons pro and contra Schuhmann’s interpolation and concludes against it, because it is not compatible with the rationale underlying the complex architecture of "De corpore", which involves a symmetry between the ‘logical’ distinction of accidents and the ‘metaphysical’ distinction of phantasms.

  10. Digital electronic bone growth stimulator

    Energy Technology Data Exchange (ETDEWEB)

    Kronberg, James W. (Aiken, SC)

    1995-01-01

    A device for stimulating bone tissue by applying a low level alternating current signal directly to the patient's skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures.

  11. Digital electronic bone growth stimulator

    Energy Technology Data Exchange (ETDEWEB)

    Kronberg, J.W.

    1995-05-09

    A device is described for stimulating bone tissue by applying a low level alternating current signal directly to the patient`s skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures. 5 figs.

  12. Guided bone regeneration: A novel approach in the treatment of pediatric dentoalveolar trauma.

    Science.gov (United States)

    Murthy, Prashanth Sadashiva; Shivamallu, Avinash Bettahalli; Deshmukh, Seema; Nandlal, Bhojraj; Thotappa, Srilatha K

    2015-01-01

    Traumatic injuries in the primary dentition pose major challenges for management. This emergency treatment requires proper planning so as to achieve favorable results. Trauma causing severe dentoalveolar injuries, especially in children, needs an interdisciplinary approach so as to retain normal functional anatomy for that age. This article describes a clinical innovative technique, which utilizes a resorbable membrane in management of pediatric dentoalveolar trauma. The membrane was shaped to cover the multiple alveolar bone fracture, thereby favoring the healing of the bone defects. The use of this resorbable membrane maintained a secluded space for the bone growth and prevented overgrowth of the soft tissue in the region of the defect. This resulted in uneventful healing leading to well-maintained functional bone contour, which further favored the esthetic rehabilitation as well as protected the underlying permanent tooth buds.

  13. Guided bone regeneration: A novel approach in the treatment of pediatric dentoalveolar trauma

    Science.gov (United States)

    Murthy, Prashanth Sadashiva; Shivamallu, Avinash Bettahalli; Deshmukh, Seema; Nandlal, Bhojraj; Thotappa, Srilatha K.

    2015-01-01

    Traumatic injuries in the primary dentition pose major challenges for management. This emergency treatment requires proper planning so as to achieve favorable results. Trauma causing severe dentoalveolar injuries, especially in children, needs an interdisciplinary approach so as to retain normal functional anatomy for that age. This article describes a clinical innovative technique, which utilizes a resorbable membrane in management of pediatric dentoalveolar trauma. The membrane was shaped to cover the multiple alveolar bone fracture, thereby favoring the healing of the bone defects. The use of this resorbable membrane maintained a secluded space for the bone growth and prevented overgrowth of the soft tissue in the region of the defect. This resulted in uneventful healing leading to well-maintained functional bone contour, which further favored the esthetic rehabilitation as well as protected the underlying permanent tooth buds. PMID:26005471

  14. Ancient Human Bone Microstructure in Medieval England: Comparisons between Two Socio-Economic Groups

    OpenAIRE

    Miszkiewicz, Justyna J.; Mahoney, Patrick

    2016-01-01

    Understanding the links between bone microstructure and human lifestyle is critical for clinical and anthropological research into skeletal\\ud growth and adaptation. The present study is the first to report correspondence between socio-economic status and variation in bone microstructure\\ud in ancient humans. Products of femoral cortical remodeling were assessed using histological methods in a large human medieval\\ud sample (N:450) which represented two distinct socio-economic groups. Osteona...

  15. Natural bone-like biomimetic surface modification of titanium

    Science.gov (United States)

    Yoon, Il-Kyu; Hwang, Ji-Young; Jang, Won-Cheoul; Kim, Hae-Won; Shin, Ueon Sang

    2014-05-01

    An implantable metallic surface consisting of titanium (Ti) was modified with natural bone-mimicking CNT-Gelatin-HA nanohybrids to create a new surface with similar properties to the surrounding bone tissue in terms of the chemical constitution, nanotopography, wettability, and biocompatibility. The biomimetic surface modification was achieved through the covalent immobilization of carbon nanotubes (CNTs) onto the Ti surface, the covalent tethering of gelatin molecules onto the CNT surface, and then the deposition of hydroxyl apatite (HA) crystals onto the gelatin-tethered CNTs in SBF solution. The SEM microscopic images demonstrated that the modified Ti surface continually maintained a fibrous structure of CNTs, but that the CNT fibers were hybridized with gelatin and HA in a multi-core-shell structure of similar constitution to that of the collagen fibers of natural bone. The new surface of the Ti substrates showed significantly higher mechanical properties and favorable wettability and biocompatibility.

  16. Low-dose computed tomography to diagnose fetal bone dysplasias.

    Science.gov (United States)

    Montoya Filardi, A; Guasp Vizcaíno, M; Gómez Fernández-Montes, J; Llorens Salvador, R

    We present a case of cleidocranial dysplasia diagnosed by low-dose fetal computed tomography (CT) in the 25th week of gestation. Severe bone dysplasia was suspected because of the fetus' low percentile in long bones length and the appearance of craniosynostosis on sonography. CT found no abnormalities incompatible with life. The effective dose was 5 mSv, within the recommended range for this type of examination. Low-dose fetal CT is a new technique that makes precision study of the bony structures possible from the second trimester of pregnancy. In Spain, abortion is legal even after the 22nd week of gestation in cases of severe fetal malformations. Therefore, in cases in which severe bone dysplasia is suspected, radiologists must know the strategies for reducing the dose of radiation while maintaining sufficient diagnostic quality, and they must also know which bony structures to evaluate.

  17. Intraosseous myoepithelioma: A rare, distinct tumor entity

    Directory of Open Access Journals (Sweden)

    Bharat Rekhi

    2014-01-01

    Full Text Available Primary musculoskeletal myoepithelial tumors (METs are distinctly rare tumors and are being increasingly recognized as a result of improved diagnostic criteria and objective confirmation with immunohistochemical markers, including epithelial markers. Recent studies have unraveled distinct molecular mechanisms underlying these tumors. Herein, we present our second diagnosed case of an intraosseous MET that occurred in the tibia of a 37-year-old lady. The case is discussed with regards to current clinicopathological perspectives on these rather uncommon tumors, including our personal experience.

  18. Function of osteocytes in bone.

    Science.gov (United States)

    Aarden, E M; Burger, E H; Nijweide, P J

    1994-07-01

    Although the structural design of cellular bone (i.e., bone containing osteocytes that are regularly spaced throughout the bone matrix) dates back to the first occurrence of bone as a tissue in evolution, and although osteocytes represent the most abundant cell type of bone, we know as yet little about the role of the osteocyte in bone metabolism. Osteocytes descend from osteoblasts. They are formed by the incorporation of osteoblasts into the bone matrix. Osteocytes remain in contact with each other and with cells on the bone surface via gap junction-coupled cell processes passing through the matrix via small channels, the canaliculi, that connect the cell body-containing lacunae with each other and with the outside world. During differentiation from osteoblasts to mature osteocyte the cells lose a large part of their cell organelles. Their cell processes are packed with microfilaments. In this review we discuss the various theories on osteocyte function that have taken in consideration these special features of osteocytes. These are 1) osteocytes are actively involved in bone turnover; 2) the osteocyte network is through its large cell-matrix contact surface involved in ion exchange; and 3) osteocytes are the mechanosensory cells of bone and play a pivotal role in functional adaptation of bone. In our opinion, especially the last theory offers an exciting concept for which some biomechanical, biochemical, and cell biological evidence is already available and which fully warrants further investigations.

  19. Inducible models of bone loss.

    Science.gov (United States)

    Doucette, Casey R; Rosen, Clifford J

    2014-12-11

    Bone is an essential organ that not only confers structural stability to the organism, but also serves as a reservoir for hematopoietic elements and is thought to affect systemic homeostasis through the release of endocrine factors as well as calcium. The loss of bone mass due to an uncoupling of bone formation and bone resorption leads to increased fragility that can result in devastating fractures. Further understanding of the effects of environmental stimuli on the development of bone disease in humans is needed, and they can be studied using animal models. Here, we present established and novel methods for the induction of bone loss in mice, including manipulation of diet and environment, administration of drugs, irradiation, and surgically induced hormone deficiency. All of these models are directly related to human cases, and thus, can be used to investigate the causes of bone loss resulting from these interventions.

  20. Integration of a Finite Element Model with the DAP Bone Remodeling Model to Characterize Bone Response to Skeletal Loading

    Science.gov (United States)

    Werner, Christopher R.; Mulugeta, Lealem; Myers, J. G.; Pennline, J. A.

    2015-01-01

    NASA's Digital Astronaut Project (DAP) has developed a bone remodeling model that has been validated for predicting volumetric bone mineral density (vBMD) changes of trabecular and cortical bone in the absence of mechanical loading. The model was recently updated to include skeletal loading from exercise and free living activities to maintain healthy bone using a new daily load stimulus (DLS). This new formula was developed based on an extensive review of existing DLS formulas, as discussed in the abstract by Pennline et al. The DLS formula incorporated into the bone remodeling model utilizes strains and stress calculated from finite element model (FEM) of the bone region of interest. The proximal femur was selected for the initial application of the DLS formula, with a specific focus on the femoral neck. METHODS: The FEM was generated from CAD geometry of a femur using de-identified CT data. The femur was meshed using linear tetrahedral elements Figure (1) with higher mesh densities in the femoral neck region, which is the primary region of interest for the initial application of the DLS formula in concert with the DAP bone remodeling model. Nodal loads were applied to the femoral head and the greater trochanter and the base of the femur was held fixed. An L2 norm study was conducted to reduce the length of the femoral shaft without significantly impacting the stresses in the femoral neck. The material properties of the FEM of the proximal femur were separated between cortical and trabecular regions to work with the bone remodeling model. Determining the elements with cortical material properties in the FEM was based off of publicly available CT hip scans [4] that were segmented, cleaned, and overlaid onto the FEM.

  1. Effects of ipriflavone on augmented bone using a guided bone regeneration procedure.

    Science.gov (United States)

    Ito, Koichi; Minegishi, Tadashi; Takayama, Tadahiro; Tamura, Takanori; Yamada, Yutaka; Sato, Shuichi

    2007-02-01

    : This study investigated the effects of ipriflavone (IP) on augmented bone using a guided bone regeneration (GBR) procedure. In 15 rabbits, two titanium caps were placed into calvarial bone for GBR. The animals were divided into three groups: the No-IP (no intake of IP), Post-IP (IP orally, 10 mg/kg/day after GBR), and Pre-IP (IP intake beginning before GBR) groups. One cap was removed from each rabbit after 3 months, and the remaining site was a control. One month after one cap removal, all the animals were euthanized, and histologic and histomorphometric analyses were performed. In all of the groups, the newly generated tissue was of varying size, and it consisted of thin pieces of mineralized bone and large marrow spaces with fat cells and some hematopoietic cells. In all of the control sites, the newly generated tissue was noted and almost filled the space under the cap. There was a significant difference between groups No-IP and Pre-IP (93.8+/-4.6% vs. 98.5+/-0.8%, Ptissue generated at the test sites in all of the groups was resorbed, and its original shape and volume were not maintained 1 month after one cap removal. In particular, the greatest percentage, approximately 20% of the newly generated tissue, was resorbed in the No-IP group (93.8+/-4.6% vs. 73.9+/-3.7%, Ptissue generated appeared to increase with an increase in the total IP dose. Within the limitations of this rabbit experimental model, we conclude that the daily intake of IP before or after GBR inhibits the resorption of augmented tissue and would be useful for improving the quality of newly generated bone beyond the skeletal envelope.

  2. 19 CFR 163.2 - Persons required to maintain records.

    Science.gov (United States)

    2010-04-01

    ... brokers. Each customs broker must also make and maintain records and make such records available in... 19 Customs Duties 2 2010-04-01 2010-04-01 false Persons required to maintain records. 163.2 Section 163.2 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND...

  3. Object Representations Maintain Attentional Control Settings across Space and Time

    Science.gov (United States)

    Schreij, Daniel; Olivers, Christian N. L.

    2009-01-01

    Previous research has revealed that we create and maintain mental representations for perceived objects on the basis of their spatiotemporal continuity. An important question is what type of information can be maintained within these so-called object files. We provide evidence that object files retain specific attentional control settings for…

  4. Polarization maintaining large-mode area photonic crystal fibre

    DEFF Research Database (Denmark)

    Folkenberg, Jacob Riis; Nielsen, Martin Dybendal; Mortensen, N.A.

    2004-01-01

    We report on a polarization maintaining large mode area photonic crystal fiber. Unlike, previous work on polarization maintaining photonic crystal fibers, birefringence is introduced using stress applying parts. This has allowed us to realize fibers, which are both single mode at any wavelength a...

  5. Coherent Beam Combination of Two Polarization Maintaining Ytterbium Fibre Amplifiers

    Institute of Scientific and Technical Information of China (English)

    HOU Jing; XIAO Rui; JIANG Zong-Fu; CHENG Xiang-Ai; SHU Bai-Hong; CHEN Jin-Bao; LIU Ze-Jin

    2005-01-01

    @@ We investigate coherent beam combination of fibre laser beams by phase locking. Phase noise of a polarization maintaining ytterbium fibre amplifier is inspected with a fibre interferometer. In a feed back control loop, two fibre polarization maintaining ytterbium amplifiers are phase locked and coherent combined when the phase noise is properly controlled by a LiNO3 phase modulator.

  6. 34 CFR 668.163 - Maintaining and accounting for funds.

    Science.gov (United States)

    2010-07-01

    ...) Accounting and internal control systems and financial records. (1) An institution must maintain accounting... financial records in accordance with the provisions under § 668.24. (e) Standard of conduct. An institution... 34 Education 3 2010-07-01 2010-07-01 false Maintaining and accounting for funds. 668.163...

  7. Bone- and bone marrow scintigraphy in Gaucher disease type 1

    Energy Technology Data Exchange (ETDEWEB)

    Mikosch, P. [Dept. of Nuclear Medicine and Endocrinology, State Hospital Klagenfurt (Austria); Dept. of Internal Medicine II, State Hospital Klagenfurt (Austria); Zitter, F. [Dept. of Internal Medicine II, State Hospital Klagenfurt (Austria); Gallowitsch, H.J.; Lind, P. [Dept. of Nuclear Medicine and Endocrinology, State Hospital Klagenfurt (Austria); Wuertz, F. [Dept. of Pathology, State Hospital Klagenfurt (Austria); Mehta, A.B.; Hughes, D.A. [Lysosomal Storage Disorder Unit, Dept. of Academic Haematology, Royal Free and Univ. Coll. Medical School, London (United Kingdom)

    2008-07-01

    Scintigraphy is a method for imaging metabolism and should be viewed as complimentary to morphological imaging. Bone and bone marrow scintigraphy can particularly contribute to the detection of focal disease in Gaucher disease. In bone crises it can discriminate within three days after pain onset between local infection and aseptic necrosis. A further advantage of bone- and bone marrow scintigraphy is the visualization of the whole skeleton within one setting. Whole body imaging for focal lesions might thus be an objective in GD, in particular in patients complaining of several painful sites. Direct imaging of bone marrow deposits in GD by MIBI scintigraphy might be of special interest in children in whom bone marrow undergoes a developmental conversion from red to yellow marrow in the ap-pendicular skeleton. MRI interpretation in young GD patients is thus difficult in order to estimate the exact amount and extent of bone marrow infiltration by Gaucher cells. 99mTc-MIBI scintigraphy with its direct visualization of lipid storage could thus add interesting additional information not shown with other methods including MRI. Although MRI is the most accepted imaging modality in assessing the skeletal status in GD, a selective use of scintigraphy for imaging bone and bone marrow may add information in the evaluation of patients with Gaucher disease.

  8. Bone scintigraphy in Erdheim-chester disease: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, V.L.; Soares, L.M.M.; Ribeiro, V.P.B.; Coura Filho, G.B.; Sapienza, M.T.; Ono, C.R.; Watanabe, T.; Costa, P.L.A.; Hironaka, F.; Buchpiguel, C.A. [Universidade de Sao Paulo (FM/USP), SP (Brazil). Fac. de Medicina. Hospital das Clinicas

    2008-07-01

    Full text: Introduction: Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis, of unknown etiology, characterized by infiltration of foamy histiocytes. Clinically, patients usually present with bone pain, and various extraskeletal manifestations. ECD differs from Langerhans cell histiocytosis (LCH) by radiologic and immunohistochemistry features. Case report: A 57-year-old woman presented with a history of intense pain on her left hand, besides eyelid xanthelasmas and xanthoms on frontal area ten years ago. Four years late she presented with pain on hips, legs and feet. Xanthoms spread to perioral area, mento and neck. Radiographs of the hands showed osteolysis of carpal bones bilaterally, osteolysis of fifth left metacarpal bone, osteosclerosis of all metacarpal bones bilaterally, except the fifth, and osteosclerosis of the second and third proximal falanges bilaterally. The legs showed bilateral diaphyseal and metaphyseal osteosclerosis. Bone scintigraphy demonstrated increased uptake on face bone (maxilla), and symmetric intense uptake on elbows, distal radii and ulnae, hands, distal area of femurs, tibias particularly on proximal and distal area, and feet. A tibia biopsy and a biopsy of neck lesion were made. The analysis of histology and immunohistochemistry were consistent with ECD. She has been treated with a-interferon for 1,5 year, and she reports delay in xanthoms progression and bone pain remission. Discussion: ECD is an adult multisystemic xanthogranulomatous infiltrative disease of unknown etiology. It may be confused with LCH, however ECD have distinctive immunohistochemistry and radiologic findings. LCH shows typically lytic bone lesions on axial skeleton, whereas symmetrical long-bone osteosclerosis is the radiologic sign for ECD. LCH stain positive for CD1a and S-100 protein, and the electron microscopy of cytoplasm discloses Biberck granules. ECD stain positive for CD68, negative for CD1a and S-100 protein, shows absent of

  9. Common and Distinct Components in Data Fusion

    DEFF Research Database (Denmark)

    Smilde, Age K.; Mage, Ingrid; Naes, Tormod;

    2016-01-01

    and understanding their relative merits. This paper provides a unifying framework for this subfield of data fusion by using rigorous arguments from linear algebra. The most frequently used methods for distinguishing common and distinct components are explained in this framework and some practical examples are given...

  10. Distinctive Dynamic Capabilities for New Business Creation

    DEFF Research Database (Denmark)

    Rosenø, Axel; Enkel, Ellen; Mezger, Florian

    2013-01-01

    This study examines the distinctive dynamic capabilities for new business creation in established companies. We argue that these are very different from those for managing incremental innovation within a company's core business. We also propose that such capabilities are needed in both slow...

  11. Simultaneous occurrence of distinct symmetries in nuclei

    CERN Document Server

    Leviatan, A

    2015-01-01

    We show that distinct emergent symmetries, such as partial dynamical symmetry and quasi dynamical symmetry, can occur simultaneously in the same or different eigenstates of the Hamiltonian. Implications for nuclear spectroscopy in the rare-earth region and for first-order quantum phase transitions between spherical and deformed shapes, are considered.

  12. A Note on Two Basic Semantic Distinctions.

    Science.gov (United States)

    Celce, Marianne; Schwarcz, Robert M.

    This paper discusses the nature of two basic semantic distinctions--intensional/extensional, and mental/physical (mental/physical being similar to abstract/concrete but more concrete)--and how an understanding of their interaction is an essential preliminary to writing a semantically motivated grammar of English. (Author/FWB)

  13. Temporal Bone Localized Chondroblastoma.

    Science.gov (United States)

    Demirhan, Hasan; Acioğlu, Engin; Durna, Yusuf Muhammed; Yiğit, Özgür; Bozkurt, Erol Rüştü; Karagöz, Yeşim

    2015-11-01

    Chondroblastoma is a highly destructive tumor originating from immature cartilage cells. Although chondroblastoma is defined as a benign tumor, it may exhibit malign tumor behaviors such as invasion or metastasis on neighboring structures. Magnetic resonance (MR) image is a solid mass lesion, which included heterogeneous hypointense in T2A and heterogeneous minimal hyperintense in T1A with destructive expansile characteristics and millimetric calcifications. Temporal bone chondroblastomas may complicate the diagnosis because of their different histologic characteristics. Microscopically, chondroblastic cell nests and calcification of locally "chicken wire" type around the cells are observed. These tumors secrete s-100 and vimentin and are used for differential diagnosis. In this study, a temporal bone localized chondroblastoma case is presented.

  14. The importance of immunophenotyping by flow cytometry in distinction between hematogones and B lymphoblasts

    Directory of Open Access Journals (Sweden)

    Aline B. Wohlfahrt

    2015-02-01

    Full Text Available Hematogones are normal B-lineage lymphoid precursors in the bone marrow. B lymphoblasts are immature neoplastic cells present in patients with precursor B-cell acute lymphoblastic leukemia (B-ALL. Hematogones and B lymphoblasts share characteristics, such as morphological similarity often indistinct and expression of the same antigens in immunophenotypic analysis. Increased numbers of hematogones in patients with B-ALL during regeneration of bone marrow after treatment for leukemia, in cases of disease relapse or marrow transplantation, may be subject to questions about the nature and prognosis of this immature cell. This article presents information about the morphological and immunophenotypic characteristics of B lymphoid precursors and verifies the relevance of immunophenotyping by flow cytometry (FC in the distinction between those cells. This differentiation is essential to establish a correct prognosis and assist in medical decision about the most appropriate therapeutic scheme.

  15. Texture Analysis and Modified Level Set Method for Automatic Detection of Bone Boundaries in Hand Radiographs

    Directory of Open Access Journals (Sweden)

    Syaiful Anam

    2014-10-01

    Full Text Available Rheumatoid Arthritis (RA is a chronic inflammatory joint disease characterized by a distinctive pattern of bone and joint destruction. To give an RA diagnosis, hand bone radiographs are taken and analyzed. A hand bone radiograph analysis starts with the bone boundary detection. It is however an extremely exhausting and time consuming task for radiologists. An automatic bone boundary detection in hand radiographs is thus strongly required. Garcia et al. have proposed a method for automatic bone boundary detection in hand radiographs by using an adaptive snake method, but it doesn’t work for those affected by RA. The level set method has advantages over the snake method. It however often leads to either a complete breakdown or a premature termination of the curve evolution process, resulting in unsatisfactory results. For those reasons, we propose a modified level set method for detecting bone boundaries in hand radiographs affected by RA. Texture analysis is also applied for distinguishing the hand bones and other areas. Evaluating the experiments using a particular set of hand bone radiographs, the effectiveness of the proposed method has been proved.

  16. Space Nutrition: Effects on Bone and Potential Nutrition Countermeasures

    Science.gov (United States)

    Smith, Scott M.

    2008-01-01

    Optimal nutrition will be critical for crew members who embark on space exploration missions. Nutritional assessment provides an opportunity to ensure that crewmembers begin their missions in optimal nutritional status, to document changes during a mission and , if necessary, to provide intervention to maintain that status throughout the mission, and to assesses changes after landing in order to facilitate the return to their normal status as soon as possible after landing. We report here the findings from our nutritional assessment of the US astronauts who participated in the first eight International Space Station (ISS) missions. Bone loss during space flight remains one of the most critical challenges to astronaut health on space exploration missions. An increase in bone resorption of ISS crew members after flight was indicated by several markers. Vitamin D status also remains a challenge for long-duration space travelers, who lack ultraviolet light exposure in the shielded craft. Many nutrients affect bone, including calcium, protein, fatty acids, sodium, and others. Data supporting their potential as countermeasures for space flight, as published in many papers, will be reviewed in this presentation. Defining nutrient requirements, and being able to provide and maintain those nutrients on exploration missions, will be critical for maintaining crew member health. Please note, this abstract is not required for the meeting. A presentation on the topics described above will be given. This abstract is for travel documentation only.

  17. Unusual endosteally formed bone tissue in a patagonian basal sauropodomorph dinosaur.

    Science.gov (United States)

    Cerda, Ignacio A; Chinsamy, Anusuya; Pol, Diego

    2014-08-01

    Mussaurus patagonicus (Dinosauria: Sauropodomorpha) is a basal sauropodomorph from the Late Triassic of southern Argentina that is known from a large number of individuals, including juveniles, subadults, and adults. Here, we report on the occurrence of an unusual bone tissue in an individual of M. patagonicus. The rather atypical bone tissue is located within the femoral medullary cavity and also occurs within several erosion cavities of the midinner part of the cortex. This tissue is well vascularized and is composed of a matrix that consists of abundant and densely packed osteocyte lacunae. Although some features of this tissue resembles avian medullary bone, the histological features are distinctive and share more features with the pathological, reactive bone produced in extant birds in response to a retrovirus-induced disease (avian osteopetrosis). Here, we also discuss and provide histological features to effectively differentiate endosteally formed medullary bone from pathological avian osteopetrosis.

  18. Virtual temporal bone

    Institute of Scientific and Technical Information of China (English)

    QIU Ming-guo; ZHANG Shao-xiang; LIU Zheng-jin; TAN Li-wen; WANG Yu-su; DENG Jun-hui; TANG Ze-sheng

    2002-01-01

    Objective:To provide the virtual model of the temporal bone for improving 3-dimension (3D) visualization of the inner ear. Methods: Plastination technique was used to make equidistant serial thin sections 1.0 mm in thickness. On SGI workstation, a Contours+Marching Cubes algorithm was selected to reconstruct the temporal bone and intratemporal structures in 3D, then to view the middle ear, inner ear, and intratemporal structures which imitate the scenes observed by the traditional endoscopy. Results: The virtual model of the temporal bone was successfully constructed, with all reconstructed structures being represented individually or jointly and being rotated continuously in any plane. Virtual endoscopy improved 3D visualization of the middle ear, inner ear, and intratemporal structures. Conclusion: The reconstructed model can be used for the medical students to rehearse or review the surgeries on this part and for the surgeons to develop a new approach for operation. Virtual otoscopy stands as a promising new visualization technique for elucidating the structure and relation of the middle ear, inner ear, and intratemporal structures.

  19. Fancd2 and p21 function independently in maintaining the size of hematopoietic stem and progenitor cell pool in mice.

    Science.gov (United States)

    Zhang, Qing-Shuo; Watanabe-Smith, Kevin; Schubert, Kathryn; Major, Angela; Sheehan, Andrea M; Marquez-Loza, Laura; Newell, Amy E Hanlon; Benedetti, Eric; Joseph, Eric; Olson, Susan; Grompe, Markus

    2013-09-01

    Fanconi anemia patients suffer from progressive bone marrow failure. An overactive p53 response to DNA damage contributes to the progressive elimination of Fanconi anemia hematopoietic stem and progenitor cells (HSPC), and hence presents a potential target for therapeutic intervention. To investigate whether the cell cycle regulatory protein p21 is the primary mediator of the p53-dependent stem cell loss, p21/Fancd2 double-knockout mice were generated. Surprisingly double mutant mice displayed even more severe loss of HSPCs than Fancd2(-/-) single mutants. p21 deletion did not rescue the abnormal cell cycle profile and had no impact on the long-term repopulating potential of Fancd2(-/-) bone marrow cells. Collectively, our data indicate that p21 has an indispensable role in maintaining a normal HSPC pool and suggest that other p53-targeted factors, not p21, mediate the progressive elimination of HSPC in Fanconi anemia.

  20. Comparing Effective Treatments for Attention-Maintained and Escape- Maintained Behaviors in Children with Behavior Disorders: Brief Review and Analysis

    OpenAIRE

    Lauren Worcester; T. F. McLaughlin

    2013-01-01

    This literature review compares treatment for attention-maintainedversus escape maintained aberrant behavior in children with behavior disorders. Specifically, studies utilizing time out procedures, differential reinforcement procedures, noncontingent reinforcement, and functional communication training are discussed. It was found that these are effective treatments for attention-maintained behaviors; while escape extinction, positive and negative reinforcement, functional communication trai...

  1. Modalities for visualization of cortical bone remodeling: the past, present and near future

    Directory of Open Access Journals (Sweden)

    Kimberly Dawn Harrison

    2015-08-01

    Full Text Available Bone’s ability to respond to load-related phenomena and repair microdamage is achieved through the remodeling process which renews bone by activating groups of cells known as Basic Multicellular Units (BMUs. The products of BMUs, secondary osteons, have been extensively studied via classic two-dimensional (2D techniques which have provided a wealth of information on how histomorphology relates to skeletal structure and function. Remodeling is critical in maintaining healthy bone tissue; however, in osteoporotic bone imbalanced resorption results in increased bone fragility and fracture. With increasing life expectancy, such degenerative bone diseases are a growing concern. The three-dimensional (3D morphology of BMUs and their correlation to function, however, are not well characterized and little is known about the specific mechanisms that initiate and regulate their activity within cortical bone. We believe a key limitation has been the lack 3D information about BMU morphology and activity. Thus, this paper reviews methodologies for 3D investigation of cortical bone remodeling and, specifically, structures associated with BMU activity (resorption spaces and the structures they create (secondary osteons, spanning from histology to modern ex vivo imaging modalities, culminating with the growing potential of in vivo imaging. This collection of papers focuses on the theme of putting the why back into bone archytecture. Remodeling is one of two mechanisms how bone structure is dynamically modified and thus an improved 3D understanding of this fundamental process is crucial to ultimately understanding the why.

  2. The role of the BH3-only protein Noxa in bone homeostasis.

    Science.gov (United States)

    Idrus, Erik; Nakashima, Tomoki; Wang, Ling; Hayashi, Mikihito; Okamoto, Kazuo; Kodama, Tatsuhiko; Tanaka, Nobuyuki; Taniguchi, Tadatsugu; Takayanagi, Hiroshi

    2011-07-08

    Bone homeostasis is maintained by a dynamic balance between bone resorption by osteoclasts and bone formation by osteoblasts. Since excessive osteoclast activity is implicated in pathological bone resorption, understanding the mechanism underlying osteoclast differentiation, function and survival is of both scientific and clinical importance. Osteoclasts are monocyte/macrophage lineage cells with a short life span that undergo rapid apoptosis, the rate of which critically determines the level of bone resorption in vivo. However, the molecular basis of rapid osteoclast apoptosis remains obscure. Here we report the role of a BH3-only protein, Noxa (encoded by the Pmaip1 gene), in bone homeostasis using Noxa-deficient mice. Among the Bcl-2 family members, Noxa was selectively induced during osteoclastogenesis. Mice lacking Noxa exhibit a severe osteoporotic phenotype due to an increased number of osteoclasts. Noxa deficiency did not have any effect on the number of osteoclast precursor cells or the expression of osteoclast-specific genes, but led to a prolonged survival of osteoclasts. Furthermore, adenovirus-mediated Noxa overexpression remarkably reduced bone loss in a model of inflammation-induced bone destruction. This study reveals Noxa to be a crucial regulator of osteoclast apoptosis, and may provide a molecular basis for a new therapeutic approach to bone diseases.

  3. Necroptosis in spontaneously-mutated hematopoietic cells induces autoimmune bone marrow failure in mice

    Science.gov (United States)

    Xin, Junping; Breslin, Peter; Wei, Wei; Li, Jing; Gutierrez, Rafael; Cannova, Joseph; Ni, Allen; Ng, Grace; Schmidt, Rachel; Chen, Haiyan; Parini, Vamsi; Kuo, Paul C.; Kini, Ameet R.; Stiff, Patrick; Zhu, Jiang; Zhang, Jiwang

    2017-01-01

    Acquired aplastic anemia is an autoimmune-mediated bone marrow failure syndrome. The mechanism by which such an autoimmune reaction is initiated is unknown. Whether and how the genetic lesions detected in patients cause autoimmune bone marrow failure have not yet been determined. We found that mice with spontaneous deletion of the TGFβ-activated kinase-1 gene in a small subset of hematopoietic cells developed bone marrow failure which resembled the clinical manifestations of acquired aplastic anemia patients. Bone marrow failure in such mice could be reversed by depletion of CD4+ T lymphocytes or blocked by knockout of interferon-γ, suggesting a Th1-cell-mediated autoimmune mechanism. The onset and progression of bone marrow failure in such mice were significantly accelerated by the inactivation of tumor necrosis factor-α signaling. Tumor necrosis factor-α restricts autoimmune bone marrow failure by inhibiting type-1 T-cell responses and maintaining the function of myeloid-derived suppressor cells. Furthermore, we determined that necroptosis among a small subset of mutant hematopoietic cells is the cause of autoimmune bone marrow failure because such bone marrow failure can be prevented by deletion of receptor interacting protein kinase-3. Our study suggests a novel mechanism to explain the pathogenesis of autoimmune bone marrow failure. PMID:27634200

  4. Bone morphogenetic proteins: Periodontal regeneration

    Directory of Open Access Journals (Sweden)

    Subramaniam M Rao

    2013-01-01

    Full Text Available Periodontitis is an infectious inflammatory disease that results in attachment loss and bone loss. Regeneration of the periodontal tissues entails de novo formation of cementum, periodontal ligament, and alveolar bone. Several different approaches are currently being explored to achieve complete, reliable, and reproducible regeneration of periodontal tissues. The therapeutic management of new bone formation is one of the key issues in successful periodontal regeneration. Bone morphogenetic proteins form a unique group of proteins within the transforming growth factor superfamily of genes and have a vital role in the regulation in the bone induction and maintenance. The activity of bone morphogenetic proteins was first identified in the 1960s, but the proteins responsible for bone induction were unknown until the purification and cloning of human bone morphogenetic proteins in the 1980s, because of their osteoinductive potential. Bone morphogenetic proteins have gained a lot of interest as therapeutic agents for treating periodontal defects. A systematic search for data related to the use of bone morphogenetic proteins for the regeneration of periodontal defects was performed to recognize studies on animals and human (PUBMED, MEDLINE, COCHRANE, and Google search. All the studies included showed noticeable regeneration of periodontal tissues with the use of BMP.

  5. Virgin Coconut Oil Supplementation Prevents Bone Loss in Osteoporosis Rat Model

    Directory of Open Access Journals (Sweden)

    Zil Hayatullina

    2012-01-01

    Full Text Available Oxidative stress and free radicals have been implicated in the pathogenesis of osteoporosis. Therefore, antioxidant compounds have the potential to be used in the prevention and treatment of the disease. In this study, we investigated the effects of virgin coconut oil (VCO on bone microarchitecture in a postmenopausal osteoporosis rat model. VCO is a different form of coconut oil as it is rich with antioxidants. Three-month-old female rats were randomly grouped into baseline, sham-operated, ovariectomized control (Ovx, and ovariectomized rats fed with 8% VCO in their diet for six weeks (Ovx+VCO. Bone histomorphometry of the right femora was carried out at the end of the study. Rats supplemented with VCO had a significantly greater bone volume and trabecular number while trabecular separation was lower than the Ovx group. In conclusion, VCO was effective in maintaining bone structure and preventing bone loss in estrogen-deficient rat model.

  6. Virgin coconut oil supplementation prevents bone loss in osteoporosis rat model.

    Science.gov (United States)

    Hayatullina, Zil; Muhammad, Norliza; Mohamed, Norazlina; Soelaiman, Ima-Nirwana

    2012-01-01

    Oxidative stress and free radicals have been implicated in the pathogenesis of osteoporosis. Therefore, antioxidant compounds have the potential to be used in the prevention and treatment of the disease. In this study, we investigated the effects of virgin coconut oil (VCO) on bone microarchitecture in a postmenopausal osteoporosis rat model. VCO is a different form of coconut oil as it is rich with antioxidants. Three-month-old female rats were randomly grouped into baseline, sham-operated, ovariectomized control (Ovx), and ovariectomized rats fed with 8% VCO in their diet for six weeks (Ovx+VCO). Bone histomorphometry of the right femora was carried out at the end of the study. Rats supplemented with VCO had a significantly greater bone volume and trabecular number while trabecular separation was lower than the Ovx group. In conclusion, VCO was effective in maintaining bone structure and preventing bone loss in estrogen-deficient rat model.

  7. Alveolar bone preservation subsequent to miniscrew implant placement in a canine model

    DEFF Research Database (Denmark)

    Melsen, Birte; Huja, Sarandeep; Chien, Hua-Hong

    2015-01-01

    on the control side. The bone volume within the cylinders was quantified. An insertion of a dental implant was simulated bilaterally at the insertion site. The height of the clinical crown and the alveolar crest were determined on both sides. The bone turnover was assessed histomorphometrically on un...... across the healing alveolar process results in increased density not only adjacent to the screws, but also in the region where a potential dental implant would be inserted. In humans, the insertion of transcortical screws may maintain bone when for various reasons insertion of a permanent dental implant......-decalcified bucco-lingual sections stained with basic fuchsine and toluidine blue. RESULTS: Comparison of the two sides revealed a significant difference both with regard to the bone volume and morphology. The transcortical screw caused an increase in bone density and less ridge atrophy. When simulating a dental...

  8. Dietary Approaches for Bone Health: Lessons from the Framingham Osteoporosis Study.

    Science.gov (United States)

    Sahni, Shivani; Mangano, Kelsey M; McLean, Robert R; Hannan, Marian T; Kiel, Douglas P

    2015-08-01

    Osteoporosis is characterized by systemic impairment of bone mass, strength, and microarchitecture, resulting in increased risk for fragility fracture, disability, loss of independence, and even death. Adequate nutrition is important in achieving and maintaining optimal bone mass, as well as preventing this debilitating disease. It is widely accepted that adequate calcium and vitamin D intake are necessary for good bone health; however, nutritional benefits to bone go beyond these two nutrients. This review article will provide updated information on all nutrients and foods now understood to alter bone health. Specifically, this paper will focus on related research from the Framingham Osteoporosis Study, an ancillary study of the Framingham Heart Study, with data on more than 5000 adult men and women.

  9. Evidence for an interaction between exercise and nutrition for improving bone and muscle health.

    Science.gov (United States)

    Daly, Robin M; Duckham, Rachel L; Gianoudis, Jenny

    2014-06-01

    Regular exercise and adequate nutrition, particularly dietary calcium, vitamin D, and protein, are prescribed as strategies to optimize peak bone mass and maintain bone and muscle health throughout life. Although the mechanism of action of exercise and nutrition on bone and muscle health are different-exercise has a site-specific modifying effect, whereas nutrition has a permissive generalized effect-there is evidence that combining calcium (or calcium rich dairy foods) or dietary protein with exercise can have a synergetic effect on bone mass and muscle health, respectively. However, many questions still remain as to whether there is a threshold level for these nutrients to optimize the exercise-induced gains. Further studies are also needed to investigate whether other dietary factors, such as vitamin D, soy isoflavones or omega-3 fatty acids, or a multinutrient supplement, can enhance the effects of exercise on bone and muscle health.

  10. FRACTAL ANALYSIS OF TRABECULAR BONE: A STANDARDISED METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Ian Parkinson

    2011-05-01

    Full Text Available A standardised methodology for the fractal analysis of histological sections of trabecular bone has been established. A modified box counting method has been developed for use on a PC based image analyser (Quantimet 500MC, Leica Cambridge. The effect of image analyser settings, magnification, image orientation and threshold levels, was determined. Also, the range of scale over which trabecular bone is effectively fractal was determined and a method formulated to objectively calculate more than one fractal dimension from the modified Richardson plot. The results show that magnification, image orientation and threshold settings have little effect on the estimate of fractal dimension. Trabecular bone has a lower limit below which it is not fractal (λ<25 μm and the upper limit is 4250 μm. There are three distinct fractal dimensions for trabecular bone (sectional fractals, with magnitudes greater than 1.0 and less than 2.0. It has been shown that trabecular bone is effectively fractal over a defined range of scale. Also, within this range, there is more than 1 fractal dimension, describing spatial structural entities. Fractal analysis is a model independent method for describing a complex multifaceted structure, which can be adapted for the study of other biological systems. This may be at the cell, tissue or organ level and compliments conventional histomorphometric and stereological techniques.

  11. Disturbances of fluid balance reduce the image quality of bone scintigraphy. Experimental studies in mice

    Energy Technology Data Exchange (ETDEWEB)

    Cronhjort, M.; Schnell, P.-O.; Jacobsson, H. (Karolinska Sjukhuset, Stockholm (Sweden))

    1994-06-01

    The effects of hydration, dehydration and osmotic diuresis on the activity distribution of bone-seeking radiopharmaceuticals have been studied in an experimental mouse system. It was found that any change of the water balance impairs the activity distribution of the radiolabelled phosphonate in the potential bone scintigraphic image. The findings suggest that in order to maintain image quality, elderly patients should not be instructed to drink a large volume of fluid after the administration of a bone-seeking radiopharmaceutical. Further investigations, though, have to be performed in humans. (author).

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

    Directory of Open Access Journals (Sweden)

    Robert Moreau

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

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

    Science.gov (United States)

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

    2012-01-01

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

  14. 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.

  15. Carbon nanohorns accelerate bone regeneration in rat calvarial bone defect

    Science.gov (United States)

    Kasai, Takao; Matsumura, Sachiko; Iizuka, Tadashi; Shiba, Kiyotaka; Kanamori, Takeshi; Yudasaka, Masako; Iijima, Sumio; Yokoyama, Atsuro

    2011-02-01

    A recent study showed that carbon nanohorns (CNHs) have biocompatibility and possible medical uses such as in drug delivery systems. It was reported that some kinds of carbon nanomaterials such as carbon nanotubes were useful for bone formation. However, the effect of CNHs on bone tissue has not been clarified. The purpose of this study was to evaluate the effect of CNHs on bone regeneration and their possible application for guided bone regeneration (GBR). CNHs dispersed in ethanol were fixed on a porous polytetrafluoroethylene membrane by vacuum filtration. Cranial defects were created in rats and covered by a membrane with/without CNHs. At two weeks, bone formation under the membrane with CNHs had progressed more than under that without CNHs and numerous macrophages were observed attached to CNHs. At eight weeks, there was no significant difference in the amount of newly formed bone between the groups and the appearance of macrophages was decreased compared with that at two weeks. Newly formed bone attached to some CNHs directly. These results suggest that macrophages induced by CNHs are related to bone regeneration. In conclusion, the present study indicates that CNHs are compatible with bone tissue and effective as a material for GBR.

  16. Development of Bone Remodeling Model for Spaceflight Bone Physiology Analysis

    Science.gov (United States)

    Pennline, James A.; Werner, Christopher R.; Lewandowski, Beth; Thompson, Bill; Sibonga, Jean; Mulugeta, Lealem

    2015-01-01

    Current spaceflight exercise countermeasures do not eliminate bone loss. Astronauts lose bone mass at a rate of 1-2% a month (Lang et al. 2004, Buckey 2006, LeBlanc et al. 2007). This may lead to early onset osteoporosis and place the astronauts at greater risk of fracture later in their lives. NASA seeks to improve understanding of the mechanisms of bone remodeling and demineralization in 1g in order to appropriately quantify long term risks to astronauts and improve countermeasures. NASA's Digital Astronaut Project (DAP) is working with NASA's bone discipline to develop a validated computational model to augment research efforts aimed at achieving this goal.

  17. Bone Biomarkers on the Pathway to Effective Spaceflight Countermeasures

    Science.gov (United States)

    Spatz, Jordan

    2009-01-01

    Osteocyte cells are the most abundant yet least understood bone cell type in the human body. However, recent discovers in osteocyte cell biology have shed light on their importance as key mechanosensing cells regulating the bone remodeling process. Thus, we propose the first ever in vitro gene expression evaluation of osteocytes exposed to simulated microgravity to determine mechanistic pathways of their gravity sensing ability. Improved understanding of the fundamental mechanisms at the osteocyte cellular level may lead to improved treatment options to mitigate the effects of bone loss encountered by astronauts on long duration space missions and provide tailored treatment options for maintaining bone strength of immobilized/partially paralyzed patients here on Earth. Aim 1: Characterize the gene expression patterns and protein levels following exposure of murine osteocytelike cell line (MLO-Y4) to simulated microgravity using the NASA Rotating Wall Vessel (RWV) Bioreactor. Osteocytes are theorized to be the mechanosensors and transducers of mechanical load for bones, yet the biological mechanism of this action remains elusive. We propose to investigate the genetic regulation of the mechanism of the MLO-Y4 cell in the NASA Bioreactor as it is the accepted ground-based analog for simulating vector averaged microgravity.

  18. Aging and bone health in individuals with developmental disabilities.

    Science.gov (United States)

    Jasien, Joan; Daimon, Caitlin M; Maudsley, Stuart; Shapiro, Bruce K; Martin, Bronwen

    2012-01-01

    Low bone mass density (BMD), a classical age-related health issue and a known health concern for fair skinned, thin, postmenopausal Caucasian women, is found to be common among individuals with developmental/intellectual disabilities (D/IDs). It is the consensus that BMD is decreased in both men and women with D/ID. Maintaining good bone health is important for this population as fractures could potentially go undetected in nonverbal individuals, leading to increased morbidity and a further loss of independence. This paper provides a comprehensive overview of bone health of adults with D/ID, their risk of fractures, and how this compares to the general aging population. We will specifically focus on the bone health of two common developmental disabilities, Down syndrome (DS) and cerebral palsy (CP), and will discuss BMD and fracture rates in these complex populations. Gaining a greater understanding of how bone health is affected in individuals with D/ID could lead to better customized treatments for these specific populations.

  19. Aging and Bone Health in Individuals with Developmental Disabilities

    Directory of Open Access Journals (Sweden)

    Joan Jasien

    2012-01-01

    Full Text Available Low bone mass density (BMD, a classical age-related health issue and a known health concern for fair skinned, thin, postmenopausal Caucasian women, is found to be common among individuals with developmental/intellectual disabilities (D/IDs. It is the consensus that BMD is decreased in both men and women with D/ID. Maintaining good bone health is important for this population as fractures could potentially go undetected in nonverbal individuals, leading to increased morbidity and a further loss of independence. This paper provides a comprehensive overview of bone health of adults with D/ID, their risk of fractures, and how this compares to the general aging population. We will specifically focus on the bone health of two common developmental disabilities, Down syndrome (DS and cerebral palsy (CP, and will discuss BMD and fracture rates in these complex populations. Gaining a greater understanding of how bone health is affected in individuals with D/ID could lead to better customized treatments for these specific populations.

  20. Intergroup distinctiveness and differentiation : A meta-analytic integration

    NARCIS (Netherlands)

    Jetten, J; Spears, R; Postmes, T

    2004-01-01

    The authors examined the relation between perceptions of intergroup distinctiveness and intergroup differentiation in a meta-analysis. They tested the social identity theory prediction that low intergroup distinctiveness underlies differentiation (the "reactive distinctiveness" hypothesis) for effec

  1. Large aneurysmal bone cyst of iliac bone in a female child: a case report

    Directory of Open Access Journals (Sweden)

    Kumar Pawan

    2010-04-01

    Full Text Available Abstract Background Symptomatic aneurysmal bone cysts in pediatric age group with an expansile lesion in ilium is a rare occurrence. Case An 11-year-old female presented with a swelling over her right iliac region and numbness along the medial aspect of thigh. Clinicoradiological diagnosis was aneurysmal bone cyst confirmed on fine needle aspiration cytology. Excision curettage (wide margin excision of the soft tissue tumor and intralesional curettage in the region of acetabulum of the tumor was performed in view of proximity to acetabular roof and endangered hip stability. Result At follow up of 18 months, the child has full painless range of movements in the hip joint with no recurrence. Conclusions Pelvic aneurysmal bone cysts are distinctly rare in pediatric age. The lesion was associated with an atypical symptom of numbness along the femoral nerve distribution. Hip stability and range of movements were major concern in this patient. Although many treatment options are described, surgical excision still remains the mainstay. In our case, we performed excision curettage, with good outcome.

  2. The loss of activating transcription factor 4 (ATF4) reduces bone toughness and fracture toughness.

    Science.gov (United States)

    Makowski, Alexander J; Uppuganti, Sasidhar; Wadeer, Sandra A; Whitehead, Jack M; Rowland, Barbara J; Granke, Mathilde; Mahadevan-Jansen, Anita; Yang, Xiangli; Nyman, Jeffry S

    2014-05-01

    Even though age-related changes to bone tissue affecting fracture risk are well characterized, only a few matrix-related factors have been identified as important to maintaining fracture resistance. As a gene critical to osteoblast differentiation, activating transcription factor 4 (ATF4) is possibly one of these important factors. To test the hypothesis that the loss of ATF4 affects the fracture resistance of bone beyond bone mass and structure, we harvested bones from Atf4+/+ and Atf4-/- littermates at 8 and 20 weeks of age (n≥9 per group) for bone assessment across several length scales. From whole bone mechanical tests in bending, femurs from Atf4-/- mice were found to be brittle with reduced toughness and fracture toughness compared to femurs from Atf4+/+ mice. However, there were no differences in material strength and in tissue hardness, as determined by nanoindentation, between the genotypes, irrespective of age. Tissue mineral density of the cortex at the point of loading as determined by micro-computed tomography was also not significantly different. However, by analyzing local composition by Raman Spectroscopy (RS), bone tissue of Atf4-/- mice was found to have higher mineral to collagen ratio compared to wild-type tissue, primarily at 20 weeks of age. From RS analysis of intact femurs at 2 orthogonal orientations relative to the polarization axis of the laser, we also found that the organizational-sensitive peak ratio, ν1Phosphate per Amide I, changed to a greater extent upon bone rotation for Atf4-deficient tissue, implying bone matrix organization may contribute to the brittleness phenotype. Target genes of ATF4 activity are not only important to osteoblast differentiation but also in maintaining bone toughness and fracture toughness.

  3. Bone-seeking therapeutic radiopharmaceuticals

    Directory of Open Access Journals (Sweden)

    Srivastava Suresh C.

    2002-01-01

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

  4. Distribution Principle of Bone Tissue

    CERN Document Server

    Fan, Yifang; Fan, Yubo; Xu, Zongxiang; Li, Zhiyu

    2009-01-01

    Using the analytic and experimental techniques we present an exploratory study of the mass distribution features of the high coincidence of centre of mass of heterogeneous bone tissue in vivo and its centroid of geometry position. A geometric concept of the average distribution radius of bone issue is proposed and functional relation of this geometric distribution feature between the partition density and its relative tissue average distribution radius is observed. Based upon the mass distribution feature, our results suggest a relative distance assessment index between the center of mass of cortical bone and the bone center of mass and establish a bone strength equation. Analysing the data of human foot in vivo, we notice that the mass and geometric distribution laws have expanded the connotation of Wolff's law, which implies a leap towards the quantitative description of bone strength. We finally conclude that this will not only make a positive contribution to help assess osteoporosis, but will also provide...

  5. SWALLOWED FISH BONES IN MALI

    Directory of Open Access Journals (Sweden)

    Sacko HB

    2015-07-01

    Full Text Available Objective: To study the different aspects, clinical, diagnostic and therapeutic of 114 cases of fish bones in the upper digestive tract . Methods: One hundred fourteen patients with fish bones suspected in the upper digestive tract were admitted in our department between February 2010 and October 2012. Results: There was a predominance of the male: 66 men (58%. The average age of the patients was 26 years with extremes 3 to 62 years old. The tongue base and vallecula are constituted the principals locations 66.66%. In the majority of the cases the fish bones were removed by direct pharyngoscopy in 43.86 %. We have not notified any serious complications. Conclusion: Therefore this study shows the foreign fish bones are frequently just as well in children as adult. The fish bones are particularly lodged in tongue base. The classical methods of extraction are permit to remove the all foreign fish bones.

  6. Bone disease and HIV infection.

    Science.gov (United States)

    Amorosa, Valerianna; Tebas, Pablo

    2006-01-01

    The high prevalence of bone demineralization among human immunodeficiency virus (HIV)-infected patients in the current therapeutic era has been described in multiple studies, sounding the alarm that we may expect an epidemic of fragility fractures in the future. However, despite noting high overall prevalences of osteopenia and osteoporosis, recent longitudinal studies that we review here have generally not observed accelerated bone loss during antiretroviral therapy beyond the initial period after treatment initiation. We discuss the continued progress toward understanding the mechanisms of HIV-associated bone loss, particularly the effects of HIV infection, antiretroviral therapy, and host immune factors on bone turnover. We summarize results of clinical trials published in the past year that studied the safety and efficacy of treatment of bone loss in HIV-infected patients and provide provisional opinions about who should be considered for bone disease screening and treatment.

  7. Bone healing around nanocrystalline hydroxyapatite, deproteinized bovine bone mineral, biphasic calcium phosphate, and autogenous bone in mandibular bone defects

    DEFF Research Database (Denmark)

    Broggini, Nina; Bosshardt, Dieter D; Jensen, Simon S;

    2015-01-01

    The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled with nanocr......The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled...... with nanocrystalline hydroxyapatite (HA-SiO), deproteinized bovine bone mineral (DBBM), biphasic calcium phosphate (BCP) with a 60/40% HA/β-TCP (BCP 60/40) ratio, or particulate autogenous bone (A) for histological and histomorphometric analysis. At 2 weeks, percent filler amongst the test groups (DBBM (35.65%), HA...

  8. A novel surgical procedure for bridging of massive bone defects

    Directory of Open Access Journals (Sweden)

    Springfield Dempsey S

    2005-02-01

    Full Text Available Abstract Background Bony defects arising from tumor resection or debridement after infection, non-union or trauma present a challenging problem to orthopedic surgeons, as well as patients due to compliance issues. Current treatment options are time intensive, require more than one operation and are associated with high rate of complications. For this reason, we developed a new surgical procedure to bridge a massive long bone defect. Methods To bridge the gap, an in situ periosteal sleeve is elevated circumferentially off of healthy diaphyseal bone adjacent to the bone defect. Then, the adjacent bone is osteotomized and the transport segment is moved along an intramedullary nail, out of the periosteal sleeve and into the original diaphyseal defect, where it is docked. Vascularity is maintained through retention of the soft tissue attachments to the in situ periosteal sleeve. In addition, periosteal osteogenesis can be augmented through utilization of cancellous bone graft or in situ cortical bone adherent to the periosteal sleeve. Results The proposed procedure is novel in that it exploits the osteogenic potential of the periosteum by replacing the defect arising from resection of tissue out of a pathological area with a defect in a healthy area of tissue, through transport of the adjacent bone segment. Furthermore, the proposed procedure has several advantages over the current standard of care including ease of implementation, rapid patient mobilization, and no need for specialized implants (intramedullary nails are standard inventory for surgical oncology and trauma departments or costly orthobiologics. Conclusions The proposed procedure offers a viable and potentially preferable alternative to the current standard treatment modalities, particularly in areas of the world where few surgeons are trained for procedures such as distraction osteogenesis (e.g. the Ilizarov procedure as well as areas of the world where surgeons have little access to

  9. Knowledge-making distinctions in synthetic biology.

    Science.gov (United States)

    O'Malley, Maureen A; Powell, Alexander; Davies, Jonathan F; Calvert, Jane

    2008-01-01

    Synthetic biology is an increasingly high-profile area of research that can be understood as encompassing three broad approaches towards the synthesis of living systems: DNA-based device construction, genome-driven cell engineering and protocell creation. Each approach is characterized by different aims, methods and constructs, in addition to a range of positions on intellectual property and regulatory regimes. We identify subtle but important differences between the schools in relation to their treatments of genetic determinism, cellular context and complexity. These distinctions tie into two broader issues that define synthetic biology: the relationships between biology and engineering, and between synthesis and analysis. These themes also illuminate synthetic biology's connections to genetic and other forms of biological engineering, as well as to systems biology. We suggest that all these knowledge-making distinctions in synthetic biology raise fundamental questions about the nature of biological investigation and its relationship to the construction of biological components and systems.

  10. Distinct types of eigenvector localization in networks

    CERN Document Server

    Pastor-Satorras, Romualdo

    2016-01-01

    The spectral properties of the adjacency matrix provide a trove of information about the structure and function of complex networks. In particular, the largest eigenvalue and its associated principal eigenvector are crucial in the understanding of node's centrality and the unfolding of dynamical processes. Here we show that two distinct types of localization of the principal eigenvector may occur in heterogeneous networks. For synthetic networks with degree distribution $P(q) \\sim q^{-\\gamma}$, localization occurs on the largest hub if $\\gamma>5/2$; for $\\gamma<5/2$ a new type of localization arises on a mesoscopic subgraph associated to the shell with the largest index in the $K$-core decomposition. Similar evidence for the existence of distinct localization modes is found in the analysis of real-world networks. Our results open a new perspective on dynamical processes on networks and on a recently proposed alternative measure of node centrality based on the non-backtracking matrix.

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

    Institute of Scientific and Technical Information of China (English)

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

    2007-01-01

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

  12. The role of muscle loading on bone (Remodeling at the developing enthesis.

    Directory of Open Access Journals (Sweden)

    Alexander M Tatara

    Full Text Available Muscle forces are necessary for the development and maintenance of a mineralized skeleton. Removal of loads leads to malformed bones and impaired musculoskeletal function due to changes in bone (remodeling. In the current study, the development of a mineralized junction at the interface between muscle and bone was examined under normal and impaired loading conditions. Unilateral mouse rotator cuff muscles were paralyzed using botulinum toxin A at birth. Control groups consisted of contralateral shoulders injected with saline and a separate group of normal mice. It was hypothesized that muscle unloading would suppress bone formation and enhance bone resorption at the enthesis, and that the unloading-induced bony defects could be rescued by suppressing osteoclast activity. In order to modulate osteoclast activity, mice were injected with the bisphosphonate alendronate. Bone formation was measured at the tendon enthesis using alizarin and calcein fluorescent labeling of bone surfaces followed by quantitative histomorphometry of histologic sections. Bone volume and architecture was measured using micro computed tomography. Osteoclast surface was determined via quantitative histomorphometry of tartrate resistant acid phosphatase stained histologic sections. Muscle unloading resulted in delayed initiation of endochondral ossification at the enthesis, but did not impair bone formation rate. Unloading led to severe defects in bone volume and trabecular bone architecture. These defects were partially rescued by suppression of osteoclast activity through alendronate treatment, and the effect of alendronate was dose dependent. Similarly, bone formation rate was increased with increasing alendronate dose across loading groups. The bony defects caused by unloading were therefore likely due to maintained high osteoclast activity, which normally decreases from neonatal through mature timepoints. These results have important implications for the treatment of

  13. Osteoprotective Effects of Estrogen in the Maxillary Bone Depend on ERα.

    Science.gov (United States)

    Macari, S; Ajay Sharma, L; Wyatt, A; Knowles, P; Szawka, R E; Garlet, G P; Grattan, D R; Dias, G J; Silva, T A

    2016-06-01

    Estrogen deficiency results in disruption of maxillary alveolar bone microarchitecture. Most of the actions of estrogen in long bones occur via estrogen receptor α (ERα). However, the function of ERα in the maxillary bone has not been defined. We aimed to investigate the role and underlying mechanisms of ERα in the physiological and mechanically induced alveolar bone remodeling in female and male mice. Wild-type (WT) and ERα(-/-) (ERKOα) mice were subjected to mechanically stimulated bone remodeling by inducing orthodontic tooth movement (OTM). The maxillary bone was analyzed using histomorphometric analysis, micro-computed tomography, quantitative polymerase chain reaction, and energy-dispersive spectroscopy. Bone marrow cells (BMCs) from WT and ERKOα mice were tested for their capacity to differentiate into osteoblasts and osteoclasts. Both male and female ERKOα mice exhibited marked reduction of alveolar bone mass and increased OTM. This response was associated with an increased number of osteoclasts and reduced number of apoptotic cells and osteoblasts in the periodontium and alveolar bone. Consistently, ERKOα mice exhibited lower levels of calcium in bone and increased expression of IL-33 (interleukin-33), TNF-α (tumor necrosis factor α), and IL-1β (interleukin-1β) and decreased expression of dentin matrix acidic phosphoprotein and alkaline phosphatase in periodontal tissues. Moreover, the differentiation of osteoclasts and osteoblasts in vitro was significantly higher in BMCs obtained from ERKOα. ERα is required to maintain the microarchitecture of maxillary alveolar bone. This process is linked to bone cell differentiation and apoptosis, as well as local production of inflammatory molecules such as IL-33, TNF-α, and IL-1β.

  14. Augmentation of the rat jaw with autogeneic cortico-cancellous bone grafts and guided tissue regeneration.

    Science.gov (United States)

    Donos, Nikolaos; Kostopoulos, Lambros; Karring, Thorkild

    2002-04-01

    The aim of the present study was to evaluate the effect of augmenting the maxillary alveolar ridge and the lateral aspect of the mandible with onlay autogeneic cortico-cancellous bone grafts that were covered with e-PTFE membranes. The experiment was carried out in 51 rats. In 15 rats, the edentulous maxillary jaw between the incisor and the first molar was augmented by means of an autogeneic ischiac bone graft that was fixed with a gold-coated microimplant. In one side, the graft was covered with an e-PTFE membrane, while the other side, which served as control, was treated without a membrane. In the other 36 rats, the lateral aspect of the mandible was augmented in both sides by means of an autogeneic ischiac bone graft that was fixed with a gold-coated or a titanium microimplant. In one side, the augmented area was covered with an e-PTFE membrane, while the contralateral side was treated without a membrane. Histological analysis at 60, 120 and 180 days after augmentation of the maxilla showed that, in the case of the test sites (where most of the membranes were either exposed or lost), the bone grafts presented extensive resorption and there was a lack of bone continuity between the graft and the recipient site. Similar findings were made at the non-membrane-treated control sides. In the case of augmentation of the mandible with membranes, the bone grafts were not resorbed, but were integrated into newly formed bone at the recipient site. In the control sides, the grafts presented varying degrees of resorption and integration into the recipient bone. It is concluded that, in comparison to bone grafting alone, onlay ischiac bone grafting combined with guided tissue regeneration eliminates the risk of bone graft resorption and ensures integration of the graft into newly formed bone at the recipient site, provided that closure of the operated area can be maintained during healing.

  15. A method for generation of bone marrow-derived macrophages from cryopreserved mouse bone marrow cells.

    Directory of Open Access Journals (Sweden)

    Fernanda M Marim

    Full Text Available The broad use of transgenic and gene-targeted mice has established bone marrow-derived macrophages (BMDM as important mammalian host cells for investigation of the macrophages biology. Over the last decade, extensive research has been done to determine how to freeze and store viable hematopoietic human cells; however, there is no information regarding generation of BMDM from frozen murine bone marrow (BM cells. Here, we establish a highly efficient protocol to freeze murine BM cells and further generate BMDM. Cryopreserved murine BM cells maintain their potential for BMDM differentiation for more than 6 years. We compared BMDM obtained from fresh and frozen BM cells and found that both are similarly able to trigger the expression of CD80 and CD86 in response to LPS or infection with the intracellular bacteria Legionella pneumophila. Additionally, BMDM obtained from fresh or frozen BM cells equally restrict or support the intracellular multiplication of pathogens such as L. pneumophila and the protozoan parasite Leishmania (L. amazonensis. Although further investigation are required to support the use of the method for generation of dendritic cells, preliminary experiments indicate that bone marrow-derived dendritic cells can also be generated from cryopreserved BM cells. Overall, the method described and validated herein represents a technical advance as it allows ready and easy generation of BMDM from a stock of frozen BM cells.

  16. Coastal Maintained Channels in US waters as of May 2013

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This layer shows coastal channels and waterways that are maintained and surveyed by the U.S. Army Corps of Engineers (USACE). These channels are necessary...

  17. An Improved Functional Hierarchy Frame Model for System Maintainability

    Institute of Scientific and Technical Information of China (English)

    CHEN Dai-Lin; CHEN Dong-lin; WANG Ru-gen; ZHU Xue-ping

    2003-01-01

    By means of analogy, this paper analyses the present functional hierarchy frame model for system maintainability, and presents an improved model. Practical application indicates that the improved model is visualized, more convenient and perfected over the pervious models.

  18. Allocating SMART Reliability and Maintainability Goals to NASA Ground Systems

    Science.gov (United States)

    Gillespie, Amanda; Monaghan, Mark

    2013-01-01

    This paper will describe the methodology used to allocate Reliability and Maintainability (R&M) goals to Ground Systems Development and Operations (GSDO) subsystems currently being designed or upgraded.

  19. 36 CFR 1222.34 - How must agencies maintain records?

    Science.gov (United States)

    2010-07-01

    ... ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS Agency Recordkeeping Requirements... organizing and storing records; (b) Maintain electronic, audiovisual and cartographic, and microform records in accordance with 36 CFR parts 1236, 1237, and 1238 of this subchapter, respectively; (c)...

  20. Epistemological Distinctions Between Science and History

    CERN Document Server

    Courtney, Michael

    2008-01-01

    This article describes epistemological distinctions between science and history. Science investigates models of natural law using repeatable experiments as the ultimate arbiter. In contrast, history investigates past events by considering physical evidence, documentary evidence, and eyewitness testimony. Because questions of natural law are repeatably testable by any audience that exercises due experimental care, models of natural law are inherently more objective and testable with greater certainty than theories of past events.

  1. Acceptance and Commitment Therapy: Distinctive Features

    OpenAIRE

    Flaxman, Paul E.; Blackledge, J. T.; Bond, Frank W.

    2010-01-01

    What are the distinctive theoretical and practical features of acceptance and commitment therapy? Acceptance and commitment therapy (ACT) is a modern behaviour therapy that uses acceptance and mindfulness interventions alongside commitment and behaviour change strategies to enhance psychological flexibility. Psychological flexibility refers to the ability to contact the present moment and change or persist in behaviour that serves one’s personally chosen values. Divided into two secti...

  2. Distinct Presentations of Hernia of Umbilical Cord

    Science.gov (United States)

    Mirza, Bilal; Ali, Waqas

    2016-01-01

    Hernia of umbilical cord is a well-known entity which presents with herniation of small bowel into the proximal part of umbilical cord. It has very good prognosis after surgical repair. Occasionally, it can have distinct presentations and varied malformations at the umbilicus which have bearing on the course of treatment and final outcome. Herein, we describe various presentations and malformations associated with hernia of umbilical cord. Embryological extrapolation is attempted for the malformations at umbilicus. PMID:27896161

  3. Mushrooms—Biologically Distinct and Nutritionally Unique

    OpenAIRE

    Feeney, Mary Jo; Miller, Amy Myrdal; Roupas, Peter

    2014-01-01

    Mushrooms are fungi, biologically distinct from plant- and animal-derived foods (fruits, vegetables, grains, dairy, protein [meat, fish, poultry, legumes, nuts, and seeds]) that comprise the US Department of Agriculture food patterns operationalized by consumer-focused MyPlate messages. Although mushrooms provide nutrients found in these food groups, they also have a unique nutrient profile. Classified into food grouping systems by their use as a vegetable, mushrooms’ increasing use in main e...

  4. Create three distinct career paths for innovators.

    Science.gov (United States)

    O'Connor, Gina Colarelli; Corbett, Andrew; Pierantozzi, Ron

    2009-12-01

    Large companies say they Create Three Distinct want to be Career Paths for Innovators innovative, but they fundamentally mismanage their talent. Expecting innovators to grow along with their projects-from discovery to incubation to acceleration--sets them up to fail. Most people excel at one of the phases, not all three. By allowing innovation employees to develop career paths suited to their strengths, companies will create a sustainable innovation function.

  5. Bone disease in primary hypercalciuria

    OpenAIRE

    Sella, Stefania; Cattelan, Catia; Realdi, Giuseppe; Giannini, Sandro

    2008-01-01

    Primary Hypercalciuria (PH) is very often accompanied with some degrees of bone demineralization. The most frequent clinical condition in which this association has been observed is calcium nephrolithiasis. In patients affected by this disorder bone density is very frequently low and increased susceptibility to fragility fractures is reported. The very poor definition of this bone disease from a histomorphometric point of view is a crucial aspect. At present, the most common finding seems to ...

  6. Gonadal dysgenesis and bone metabolism.

    Science.gov (United States)

    Breuil, V; Euller-Ziegler, L

    2001-02-01

    Gonadal dysgenesis is defined as congenital hypogonadism related to abnormalities of the sex chromosomes. Because sex steroids play a central role in the acquisition and maintenance of bone mass, studies have been done to investigate bone status in patients with gonadal dysgenesis, particularly Turner's syndrome and Klinefelter's syndrome, which are the two most common types. The severe estrogen deficiency characteristic of Turner's syndrome (44, X0) is associated with a significant bone mass decrease ascribable to increased bone turnover, as shown by histological studies and assays of bone turnover markers. Estrogen therapy is followed by a significant bone mass gain and a return to normal of bone turnover markers, suggesting that it is the estrogen deficiency rather than the chromosomal abnormality that causes the bone mass deficiency, although abnormalities in the renal metabolism of vitamin D have been reported. Combined therapy with estrogens and growth hormone seems beneficial during the prepubertal period. In Klinefelter's syndrome (47XXY), serum testosterone levels are at the lower end of the normal range and dihydrotestosterone levels are low. Histological studies show depressed osteoblast function and a decrease in 5-alpha-reductase activity responsible for partial tissue resistance to androgens. Assays of bone turnover markers show evidence of increased bone turnover. The bone deficiency is most marked at the femoral neck and seems correlated with serum testosterone and estradiol levels. Androgen therapy has favorable effects on the bone only if it is started before puberty. Recent data suggest that estrogens may contribute to the development of demineralization in KS and that bisphosphonate therapy may be beneficial.

  7. Dietary Habits, Nutrients and Bone Mass in Spanish Premenopausal Women: The Contribution of Fish to Better Bone Health

    Directory of Open Access Journals (Sweden)

    Julian F. Calderon-Garcia

    2012-12-01

    Full Text Available The moderate consumption of fish is recommended for a healthy diet and is also a feature of the Mediterranean diet. Fish is a major food group in diets throughout the world, and studies show that fish consumption is associated with a lower risk of a number of conditions. Spain has one of the highest annual per capita consumptions of fish worldwide. As fish is a source of high quality protein; n-3 polyunsaturated fatty acids; vitamins, such as A and D; and minerals, such as selenium, calcium, iodine, magnesium, copper and zinc, nutrients that have positive effects on bone characteristics, it has been proposed that its consumption could improve bone health. In this cross-sectional study, we have investigated the relationship between dietary habits and nutrient intake of 151 Spanish premenopausal women and analyzed the association of fish consumption on bone mass measured by quantitative ultrasound of the phalanges. A higher (P < 0.05 bone mass and vitamin D intake (P < 0.05 was observed in the group with a fish intake of 5–7 servings/week. We conclude that increased fish consumption is helpful in maintaining an adequate bone mass in Spanish premenopausal women.

  8. Dietary habits, nutrients and bone mass in Spanish premenopausal women: the contribution of fish to better bone health.

    Science.gov (United States)

    Calderon-Garcia, Julian F; Moran, Jose M; Roncero-Martin, Raul; Rey-Sanchez, Purificacion; Rodriguez-Velasco, Francisco J; Pedrera-Zamorano, Juan D

    2012-12-27

    The moderate consumption of fish is recommended for a healthy diet and is also a feature of the Mediterranean diet. Fish is a major food group in diets throughout the world, and studies show that fish consumption is associated with a lower risk of a number of conditions. Spain has one of the highest annual per capita consumptions of fish worldwide. As fish is a source of high quality protein; n-3 polyunsaturated fatty acids; vitamins, such as A and D; and minerals, such as selenium, calcium, iodine, magnesium, copper and zinc, nutrients that have positive effects on bone characteristics, it has been proposed that its consumption could improve bone health. In this cross-sectional study, we have investigated the relationship between dietary habits and nutrient intake of 151 Spanish premenopausal women and analyzed the association of fish consumption on bone mass measured by quantitative ultrasound of the phalanges. A higher (P < 0.05) bone mass and vitamin D intake (P < 0.05) was observed in the group with a fish intake of 5-7 servings/week. We conclude that increased fish consumption is helpful in maintaining an adequate bone mass in Spanish premenopausal women.

  9. Quantum information sharing between topologically distinct platforms

    Science.gov (United States)

    Hou, Chang-Yu; Refael, Gil; Shtengel, Kirill

    2016-12-01

    Can topological quantum entanglement between anyons in one topological medium "stray" into a different, topologically distinct medium? In other words, can quantum information encoded nonlocally in the combined state of non-Abelian anyons be shared between two distinct topological media? For one-dimensional topological superconductors with Majorana bound states at the end of system, the quantum information store in those Majorana bound states can be transfered by directly coupling nearby Majorana bound states. However, coupling of two one-dimensional Majorana states will produce a gap, indicating that distinct topological regions of one-dimensional wires unite into a single topological region through the information transfer process. In this paper, we consider a setup with two two-dimensional p -wave superconductors of opposite chirality adjacent to each other. Even two comoving chiral modes at the domain wall between them cannot be gapped through interactions; we demonstrate that information encoded in the fermionic parity of two Majorana zero modes, originally within the same superconducting domain, can be shared between the domains or moved entirely from one domain to another provided that vortices can tunnel between them in a controlled fashion.

  10. Banded vs Bonded Space Maintainers: Finding Better Way Out

    OpenAIRE

    Setia, Vikas; Kumar Pandit, Inder; Srivastava, Nikhil; Gugnani, Neeraj; Gupta, Monika

    2014-01-01

    ABSTRACT Objectives: Of this in vivo study was to evaluate various space maintainers in terms of survival rate, gingival health and presence of caries. Design: A total of 60 extraction sites in the age group of 4 to 9 years were divided into four groups and different space maintainers were placed in them viz (conventional band and loop, prefabricated band with custom made loop, Ribbond, Super splint). Results: Prefabricated bands with custom made loop showed maximum success rates (84.6%), whi...

  11. Band and loop space maintainer--made easy.

    Science.gov (United States)

    Nayak, U A; Loius, J; Sajeev, R; Peter, J

    2004-09-01

    Space maintainers have been used in Pediatric Dentistry for many years. The use of these appliances, however, in terms of indications, contraindications, design and construction has gained little attention from researchers. This paper highlights the construction of a new technique of fabrication of band and loop space maintainer. The advantages of this new Direct technique or Single sitting technique over the conventional technique are discussed.

  12. Perkembangan Terkini Membran Guided Tissue Regeneration/Guided Bone Regeneration sebagai Terapi Regenerasi Jaringan Periodontal

    Directory of Open Access Journals (Sweden)

    Cindy Cahaya

    2015-06-01

    connected with oral rehabilitation with implant placement. At cellular phase, periodontal regeneration is a complex process with well-organized proliferation, distinction, and development of various type of cell to form attachment of periodontal tissue. Rationalization of the use of guided tissue regeneration as barrier membrane is to prohibit the penetration of epithelial and connective tissue migration into the defect, to maintain space, and to stabilize the clot. This research discusses: 1. Healing process on periodontal therapy including regeneration, repair or formation of new attachment. 2. Periodontal specific tissue engineering. 3. Various commercially available membrane/guided tissue regeneration in the market with its advantages and disadvantages and their characteristics. 4. Recent advancement of membrane as regenerative therapy on periodontal disease. In addition, this review is presented to give an outlook for promising regenerative therapy as a part of developing knowledge and skills to treat periodontal disease.

  13. Pyk2 and Megakaryocytes Regulate Osteoblast Differentiation and Migration Via Distinct and Overlapping Mechanisms.

    Science.gov (United States)

    Eleniste, Pierre P; Patel, Vruti; Posritong, Sumana; Zero, Odette; Largura, Heather; Cheng, Ying-Hua; Himes, Evan R; Hamilton, Matthew; Baughman, Jenna; Kacena, Melissa A; Bruzzaniti, Angela

    2016-06-01

    Osteoblast differentiation and migration are necessary for bone formation during bone remodeling. Mice lacking the proline-rich tyrosine kinase Pyk2 (Pyk2-KO) have increased bone mass, in part due to increased osteoblast proliferation. Megakaryocytes (MKs), the platelet-producing cells, also promote osteoblast proliferation in vitro and bone-formation in vivo via a pathway that involves Pyk2. In the current study, we examined the mechanism of action of Pyk2, and the role of MKs, on osteoblast differentiation and migration. We found that Pyk2-KO osteoblasts express elevated alkaline phosphatase (ALP), type I collagen and osteocalcin mRNA levels as well as increased ALP activity, and mineralization, confirming that Pyk2 negatively regulates osteoblast function. Since Pyk2 Y402 phosphorylation is important for its catalytic activity and for its protein-scaffolding functions, we expressed the phosphorylation-mutant (Pyk2(Y402F) ) and kinase-mutant (Pyk2(K457A) ) in Pyk2-KO osteoblasts. Both Pyk2(Y402F) and Pyk2(K457A) reduced ALP activity, whereas only kinase-inactive Pyk2(K457A) inhibited Pyk2-KO osteoblast migration. Consistent with a role for Pyk2 on ALP activity, co-culture of MKs with osteoblasts led to a decrease in the level of phosphorylated Pyk2 (pY402) as well as a decrease in ALP activity. Although, Pyk2-KO osteoblasts exhibited increased migration compared to wild-type osteoblasts, Pyk2 expression was not required necessary for the ability of MKs to stimulate osteoblast migration. Together, these data suggest that osteoblast differentiation and migration are inversely regulated by MKs via distinct Pyk2-dependent and independent signaling pathways. Novel drugs that distinguish between the kinase-dependent or protein-scaffolding functions of Pyk2 may provide therapeutic specificity for the control of bone-related diseases.

  14. Unexplained Bone Pain Is an Independent Risk Factor for Bone Metastases in Newly Diagnosed Prostate Cancer

    DEFF Research Database (Denmark)

    Zacho, Helle D; Mørch, Carsten D; Barsi, Tamás;

    2017-01-01

    OBJECTIVE: To determine the relationship between bone pain and bone metastases in newly diagnosed prostate cancer. PATIENTS AND METHODS: This prospective study of bone scintigraphy enrolled 567 consecutive patients with newly diagnosed prostate cancer. The presence of all-cause bone pain, known b......: Unexplained bone pain was a strong independent risk factor for bone metastasis. Guidelines should recommend staging bone scintigraphy in patients with unexplained bone pain, regardless of other risk factors....

  15. Differential actions of the endocytic collagen receptor uPARAP/Endo180 and the collagenase MMP-2 in bone homeostasis

    DEFF Research Database (Denmark)

    Madsen, Daniel H; Jürgensen, Henrik J; Ingvarsen, Signe;

    2013-01-01

    the extracellular collagenase, MMP-2, and the endocytic collagen receptor, uPARAP, by generating mice with combined deficiency of both components. In both uPARAP-deficient and MMP-2-deficient adult mice the length of the tibia and femur was decreased, along with a reduced bone mineral density and trabecular bone...... quality. An additional decrease in bone length was observed when combining the two deficiencies, pointing to both components being important for the remodeling processes in long bone growth. In agreement with results found by others, a different effect of MMP-2 deficiency was observed in the distinct bone...... structures of the calvaria. These membranous bones were found to be thickened in MMP-2-deficient mice, an effect likely to be related to an accompanying defect in the canalicular system. Surprisingly, both of the latter defects in MMP-2-deficient mice were counteracted by concurrent uPARAP deficiency...

  16. Maintaining dental records: Are we ready for forensic needs?

    Directory of Open Access Journals (Sweden)

    Madhusudan Astekar

    2011-01-01

    Full Text Available Context: Dental remains are usually the last to get destroyed among body parts after death. They may be useful for personal identification in cases of mass disasters and decomposed unidentified bodies. Dental records may help in the identification of suspects in criminal investigations and in medicolegal cases. Maintenance of dental records is legally mandatory in most of the European and American countries. Unfortunately, the law is not very clear in India, and the awareness is very poor. Aims: To assess the awareness regarding the dental record maintenance among dentists in Rajasthan, to deduce the quality of average dental records kept by them and to evaluate the potential use of their maintained records, in any of forensic or medicolegal cases. Settings and Design: A cross-sectional survey was conducted among 100 dental practitioners of different cities in Rajasthan, India. Materials and Methods: Data were collected through a structured questionnaire, which was responded by the study population in the course of a telephonic interview. The questionnaire addressed on the mode of maintaining dental records in their regular practice. Statistical Analysis Used: The data so gathered were subjected for descriptive analysis. Results: As for knowledge or awareness about maintaining dental records, surprisingly a very low percentile (about 38% of surveyed dentists maintained records. Sixty-two percent of the dentists were maintaining no records at all. Conclusion : Nonmaintenance or poor quality of records maintained indicates that the dentists in Rajasthan are not prepared for any kind of forensic and medicolegal need if it arises.

  17. Bone Repair on Fractures Treated with Osteosynthesis, ir Laser, Bone Graft and Guided Bone Regeneration: Histomorfometric Study

    Science.gov (United States)

    dos Santos Aciole, Jouber Mateus; dos Santos Aciole, Gilberth Tadeu; Soares, Luiz Guilherme Pinheiro; Barbosa, Artur Felipe Santos; Santos, Jean Nunes; Pinheiro, Antonio Luiz Barbosa

    2011-08-01

    The aim of this study was to evaluate, through the analysis of histomorfometric, the repair of complete tibial fracture in rabbits fixed with osteosynthesis, treated or not with infrared laser light (λ780 nm, 50 mW, CW) associated or not to the use of hydroxyapatite and guided bone regeneration (GBR). Surgical fractures were created, under general anesthesia (Ketamina 0,4 ml/Kg IP and Xilazina 0,2 ml/Kg IP), on the dorsum of 15 Oryctolagus rabbits that were divided into 5 groups and maintained on individual cages, at day/night cycle, fed with solid laboratory pelted diet and had water ad libidum. On groups II, III, IV and V the fracture was fixed with wire osteosynthesis. Animals of groups III and V were grafted with hydroxyapatite and GBR technique used. Animals of groups IV and V were irradiated at every other day during two weeks (16 J/cm2, 4×4 J/cm2). Observation time was that of 30 days. After animal death (overdose of general anesthetics) the specimes were routinely processed to wax and underwent histological analysis by light microscopy. The histomorfometric analysis showed an increased bone neoformation, increased collagen deposition, less reabsorption and inflammation when laser was associated to the HATCP. It is concluded that IR laser light was able to accelerate fracture healing and the association with HATCP and GBR resulted on increased deposition of CHA.

  18. Bones of the Earth

    Directory of Open Access Journals (Sweden)

    Jose Miguel Correa

    2014-06-01

    Full Text Available The film Bones of the Earth (Riglin, Cunninham & Correa, 2014 is an experience in collective inquiry and visual creation based on arts-based research. Starting from the meeting of different subjectivities and through dialogue, planning, shooting and editing, an audiovisual text that reconstructs a reflexive process of collective creation is built. A sense of community, on-going inquiry, connections and social commitment inform the creative process. As a result, the video’s nearly five intense minutes are a metaphor for the search for personal meaning, connection with nature and intersubjective positioning in a world that undergoes constant change.

  19. Bones and joints

    Energy Technology Data Exchange (ETDEWEB)

    Runge, M.

    1987-01-01

    This exercise book guides the student and the radiologist wishing to review his knowledge to rapid and correct analysis and interpretation of radiologic findings in bone and joint disorders. The first part of the volume demonstrates the radiologic findings without going into the clinical and pathological aspects. In the second part, the reader then learns to analyse and diagnose systematically the case examples by means of a complete description of the X-ray images. Contents: Introduction; iconography; commentary with corresponding schemata; references and subject index.

  20. Alendronate prevents postmenopausal bone loss in women without osteoporosis. A double-blind, randomized, controlled trial. Alendronate Osteoporosis Prevention Study Group

    DEFF Research Database (Denmark)

    McClung, M; Clemmesen, B; Daifotis, A

    1998-01-01

    BACKGROUND: Preventing bone loss associated with menopause and aging and maintaining the normal micro-architecture of bone provide important opportunities for the prevention of osteoporosis and fractures. OBJECTIVE: To determine the safety and efficacy of alendronate, an aminobisphosphonate......, for preventing postmenopausal bone loss. DESIGN: 3-year double-blind, randomized, placebo-controlled trial. SETTING: 15 osteoporosis centers throughout the world. PARTICIPANTS: 447 women who had recently experienced menopause (6 to 36 months before study entry). INTERVENTION: Participants were randomly assigned...