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Sample records for adequate bone volume

  1. Adequate dietary vitamin D and calcium are both required to reduce bone turnover and increased bone mineral volume.

    PubMed

    Lee, Alice M C; Sawyer, Rebecca K; Moore, Alison J; Morris, Howard A; O'Loughlin, Peter D; Anderson, Paul H

    2014-10-01

    Clinical studies indicate that the combination of vitamin D and dietary calcium supplementation is more effective for reducing fracture risk than either supplement alone. Our previous dietary studies demonstrated that an adequate serum 25-hydroxyvitamin D3 (25D) of 80nmol/L or more reduces bone RANKL expression, osteoclastogenesis and maintains the optimal levels of trabecular bone volume (BV/TV%) in young rats. The important clinical question of the interaction between vitamin D status, dietary calcium intake and age remains unclear. Hence, 9 month-old female Sprague-Dawley rats (n=5-6/group) were pair-fed a semi-synthetic diet containing varying levels of vitamin D (0, 2, 12 or 20IU/day) and dietary calcium (0.1% or 1%) for 6 months. At 15 months of age, animals were killed, for biochemical and skeletal analyses. While changes to serum 25D were determined by both dietary vitamin D and calcium levels, changes to serum 1,25-dihydroxyvitamin D3 (1,25D) were consistently raised in animals fed 0.1% Ca regardless of dietary vitamin D or vitamin D status. Importantly, serum cross-laps levels were significantly increased in animals fed 0.1% Ca only when combined with 0 or 2 IUD/day of vitamin D, suggesting a contribution of both dietary calcium and vitamin D in determining bone resorption activity. Serum 25(OH)D3 levels were positively correlated with both femoral mid-diaphyseal cortical bone volume (R(2)=0.24, P<0.01) and metaphyseal BV/TV% (R(2)=0.23, P<0.01, data not shown). In multiple linear regressions, serum 1,25(OH)2D3 levels were a negative determinant of CBV (R(2)=0.24, P<0.01) and were not a determinant of metaphyseal BV/TV% levels. These data support clinical data that reduced bone resorption and increased bone volume can only be achieved with adequate 25D levels in combination with high dietary calcium and low serum 1,25D levels. This article is part of a Special Issue entitled '16th Vitamin D Workshop'. PMID:24309068

  2. Supplemental Escherichia coli phytase and strontium enhance bone strength of young pigs fed a phosphorus-adequate diet.

    PubMed

    Pagano, Angela R; Yasuda, Koji; Roneker, Karl R; Crenshaw, Thomas D; Lei, Xin Gen

    2007-07-01

    Young pigs represent an excellent model of youth to assess potentials of dietary factors for improving bone structure and function. We conducted 2 experiments to determine whether adding microbial phytase (2,000 U/kg, OptiPhos, JBS United) and Sr (50 mg/kg, SrCO3 Alfa Aesar) into a P-adequate diet further improved bone strength of young pigs. In Expt. 1, 24 gilts (8.6 +/- 0.1 kg body wt) were divided into 2 groups (n = 12), and fed a corn-soybean-meal basal diet (BD, 0.33% available P) or BD + phytase for 6 wk. In Expt. 2, 32 pigs (11.4 +/- 0.2 kg) were divided into 4 groups (n = 8), and fed BD, BD + phytase, BD + Sr, or BD + phytase and Sr for 5 wk. Both supplemental phytase and Sr enhanced (P < 0.05) breaking strengths (11-20%), mineral content (6-15%), and mineral density (6-11%) of metatarsals and femurs. Supplemental phytase also resulted in larger total bone areas (P < 0.05) and a larger cross-sectional area of femur (P = 0.06). Concentrations of Sr were elevated 4-fold (P < 0.001) in both bones by Sr, and moderately increased (P = 0.05-0.07) in metatarsal by phytase. In conclusion, supplemental phytase at 2000 U/kg of P-adequate diets enhanced bone mechanical function of weanling pigs by modulating both geometrical and chemical properties of bone. The similar benefit of supplemental Sr was mainly due to an effect on bone chemical properties. PMID:17585033

  3. Adequate hypoxia inducible factor 1α signaling is indispensable for bone regeneration.

    PubMed

    Stegen, Steve; Deprez, Sanne; Eelen, Guy; Torrekens, Sophie; Van Looveren, Riet; Goveia, Jermaine; Ghesquière, Bart; Carmeliet, Peter; Carmeliet, Geert

    2016-06-01

    Engineered cell-based constructs are an appealing strategy to treat large skeletal defects. However, transplanted cells are often confronted with an environment that is deprived of oxygen and nutrients. Upon hypoxia, most cell types activate hypoxia-inducible factor 1α (HIF-1α) signaling, but its importance for implanted osteoprogenitor cells during bone regeneration is not elucidated. To this end, we specifically deleted the HIF--1α isoform in periosteal progenitor cells and show that activation of HIF-1α signaling in these cells is critical for bone repair by modulating angiogenic and metabolic processes. Activation of HIF-1α is not only crucial for blood vessel invasion, by enhancing angiogenic growth factor production, but also for periosteal cell survival early after implantation, when blood vessels have not yet invaded the construct. HIF-1α signaling limits oxygen consumption to avoid accumulation of harmful ROS and preserve redox balance, and additionally induces a switch to glycolysis to prevent energetic distress. Altogether, our results indicate that the proangiogenic capacity of implanted periosteal cells is HIF-1α regulated and that metabolic adaptations mediate post-implantation cell survival. PMID:27058876

  4. Engineering clinically relevant volumes of vascularized bone

    PubMed Central

    Roux, Brianna M; Cheng, Ming-Huei; Brey, Eric M

    2015-01-01

    Vascularization remains one of the most important challenges that must be overcome for tissue engineering to be consistently implemented for reconstruction of large volume bone defects. An extensive vascular network is needed for transport of nutrients, waste and progenitor cells required for remodelling and repair. A variety of tissue engineering strategies have been investigated in an attempt to vascularize tissues, including those applying cells, soluble factor delivery strategies, novel design and optimization of bio-active materials, vascular assembly pre-implantation and surgical techniques. However, many of these strategies face substantial barriers that must be overcome prior to their ultimate translation into clinical application. In this review recent progress in engineering vascularized bone will be presented with an emphasis on clinical feasibility. PMID:25877690

  5. Adequate Selection of a Therapeutic Site Enables Efficient Development of Collateral Vessels in Angiogenic Treatment With Bone Marrow Mononuclear Cells

    PubMed Central

    Nemoto, Masaru; Koyama, Hiroyuki; Nishiyama, Ayako; Shigematsu, Kunihiro; Miyata, Tetsuro; Watanabe, Toshiaki

    2015-01-01

    Background Induction of angiogenic mechanisms to promote development of collateral vessels is considered promising for the treatment of peripheral arterial diseases. Collateral vessels generally develop from preexisting arteriolar connections, bypassing the diseased artery. We speculated that induction of angiogenic mechanisms should be directed to such arteriolar connections to achieve efficient collateral development. The aim of this study was to verify this hypothesis using autologous transplantation of bone marrow mononuclear cells in the rabbit model of chronic limb ischemia. Methods and Results The left femoral artery was excised to induce limb ischemia in male rabbits. In this model, arteriolar connections in the left coccygeofemoral muscle tend to develop into collateral vessels, although this transformation is insufficient to alleviate the limb ischemia. In contrast, arteriolar connections in the closely located adductor muscle do not readily develop into collateral vessels. At 21 days after ischemia initiation, a sufficient number of automononuclear cells were selectively injected in the left coccygeofemoral muscle (coccygeo group) or left adductor muscle (adductor group). Evaluation of calf blood pressure ratios, blood flow in the left internal iliac artery, and angiographic scores at day 28 after injection revealed that collateral development and improvement of limb ischemia were significantly more efficient in the coccygeo group than in the adductor group. Morphometric analysis of the coccygeofemoral muscle at day 14 showed similar results. Conclusions Specific delivery of mononuclear cells to the coccygeofemoral but not the adductor muscle effectively improves collateral circulation in the rabbit model of limb ischemia and suggests that adequate site selection can facilitate therapeutic angiogenesis. PMID:26370447

  6. Gamma images in benign and metabolic bone diseases: volume 1

    SciTech Connect

    Sy, W.M.

    1981-01-01

    Volume 1 of ''Gamma images in benign and metabolic bone diseases'' comprises chapters devoted to: general remarks and considerations, radiopharmaceuticals, Paget disease, osteomyelitis, trauma, benign bone tumors, chronic renal dialysis, acute renal failure, osteomalacia and rickets, and osteoporosis. Although published in 1981, the most recent references in the book were 1978 and most are 1977 or earlier. One of the strongest aspects of the volume are tables which categorize diseases, pathophysiology of disease, and image abnormalities. (JMT)

  7. Estimation of Local Bone Loads for the Volume of Interest.

    PubMed

    Kim, Jung Jin; Kim, Youkyung; Jang, In Gwun

    2016-07-01

    Computational bone remodeling simulations have recently received significant attention with the aid of state-of-the-art high-resolution imaging modalities. They have been performed using localized finite element (FE) models rather than full FE models due to the excessive computational costs of full FE models. However, these localized bone remodeling simulations remain to be investigated in more depth. In particular, applying simplified loading conditions (e.g., uniform and unidirectional loads) to localized FE models have a severe limitation in a reliable subject-specific assessment. In order to effectively determine the physiological local bone loads for the volume of interest (VOI), this paper proposes a novel method of estimating the local loads when the global musculoskeletal loads are given. The proposed method is verified for the three VOI in a proximal femur in terms of force equilibrium, displacement field, and strain energy density (SED) distribution. The effect of the global load deviation on the local load estimation is also investigated by perturbing a hip joint contact force (HCF) in the femoral head. Deviation in force magnitude exhibits the greatest absolute changes in a SED distribution due to its own greatest deviation, whereas angular deviation perpendicular to a HCF provides the greatest relative change. With further in vivo force measurements and high-resolution clinical imaging modalities, the proposed method will contribute to the development of reliable patient-specific localized FE models, which can provide enhanced computational efficiency for iterative computing processes such as bone remodeling simulations. PMID:27109554

  8. Influence of the volume of bone defect, bone grafting methods, and hook fixation on stress on the Kerboull-type plate and screw in total hip arthroplasty: three-dimensional finite element analysis.

    PubMed

    Kaku, Nobuhiro; Hara, Katsutoshi; Tabata, Tomonori; Tsumura, Hiroshi

    2015-02-01

    For total hip arthroplasty or revision surgery using acetabular reinforcement cross-plates, choosing between bulk and morselized bone grafts for filling acetabular defects is challenging. We used finite element model (FEM) analysis to clarify various stresses on the cross-plate based on bone defect size, bone graft type, and presence or absence of hook fixation to the bone. We constructed 12-pattern FEMs and calculated the maximum stress generated on the Kerboull-type (KT) plate and screw. Bone defects were classified into four patterns according to the volume. Regarding the bone graft type, bulk bone grafts were considered as cortical bone, and morselized bone grafts were considered to consist of cancellous bone. Models were compared based on whether hook fixation was used and whether a gap was present behind the plate. The upper surface of the host bone was fixed, and a 1,000-N load was imposed on the horizontal axis at 71°. Larger bone defects increased the stress on the KT plate and screws. This stress increased when no bone was grafted; it was lower when bulk cortical bone grafts were used for filling than when morselized cancellous bone grafts were used. For cortical bone grafts, the increased stress on the KT plate and screws was lowered with hook removal. Attaching the hook to the bone and filling the gap behind the KT plate with an adequate bone graft reduced the stress on the KT plate and screws, particularly for large bone defects filled by bulk bone grafting. PMID:24964969

  9. Retrospective Reconstructions of Active Bone Marrow Dose-Volume Histograms

    SciTech Connect

    Veres, Cristina; Allodji, Rodrigue S.; Llanas, Damien; Vu Bezin, Jérémi; Chavaudra, Jean; Mège, Jean Pierre; Lefkopoulos, Dimitri; Quiniou, Eric; Deutsh, Eric; Vathaire, Florent de; Diallo, Ibrahima

    2014-12-01

    Purpose: To present a method for calculating dose-volume histograms (DVH's) to the active bone marrow (ABM) of patients who had undergone radiation therapy (RT) and subsequently developed leukemia. Methods and Materials: The study focuses on 15 patients treated between 1961 and 1996. Whole-body RT planning computed tomographic (CT) data were not available. We therefore generated representative whole-body CTs similar to patient anatomy. In addition, we developed a method enabling us to obtain information on the density distribution of ABM all over the skeleton. Dose could then be calculated in a series of points distributed all over the skeleton in such a way that their local density reflected age-specific data for ABM distribution. Dose to particular regions and dose-volume histograms of the entire ABM were estimated for all patients. Results: Depending on patient age, the total number of dose calculation points generated ranged from 1,190,970 to 4,108,524. The average dose to ABM ranged from 0.3 to 16.4 Gy. Dose-volume histograms analysis showed that the median doses (D{sub 50%}) ranged from 0.06 to 12.8 Gy. We also evaluated the inhomogeneity of individual patient ABM dose distribution according to clinical situation. It was evident that the coefficient of variation of the dose for the whole ABM ranged from 1.0 to 5.7, which means that the standard deviation could be more than 5 times higher than the mean. Conclusions: For patients with available long-term follow-up data, our method provides reconstruction of dose-volume data comparable to detailed dose calculations, which have become standard in modern CT-based 3-dimensional RT planning. Our strategy of using dose-volume histograms offers new perspectives to retrospective epidemiological studies.

  10. Strontium administration in young chickens improves bone volume and architecture but does not enhance bone structural and material strength.

    PubMed

    Shahnazari, M; Lang, D H; Fosmire, G J; Sharkey, N A; Mitchell, A D; Leach, R M

    2007-03-01

    Genetic selection for rapid body growth in broiler chickens has resulted in adverse effects on the skeletal system exemplified by a higher rate of cortical fractures in leg bones. Strontium (Sr) has been reported to have beneficial effects on bone formation and strength. We supplemented the diet of 300-day-old chicks with increasing dosages of Sr (0%, 0.12%, or 0.24%) to study the capacity of the element to improve bone quality and mechanical integrity. Treatment with Sr increased cortical bone volume and reduced bone porosity as measured by micro-computed tomography. The higher level of Sr significantly reduced bone Ca content (34.7%) relative to controls (37.2%), suggesting that Sr replaced some of the Ca in bone. Material properties determined by the three-point bending test showed that bone in the Sr-treated groups withstood greater deformation prior to fracture. Load to failure and ultimate stress were similar across groups. Our results indicate that Sr treatment in rapidly growing chickens induced positive effects on bone volume but did not improve the breaking strength of long bones. PMID:17340224

  11. Quantitative Comparison of Volume Maintenance between Inlay and Onlay Bone Grafts in the Craniofacial Skeleton

    PubMed Central

    Sugg, Kristoffer B.; Rosenthal, Andrew H.; Ozaki, Wayne; Buchman, Steven R.

    2015-01-01

    Background Nonvascularized autologous bone grafts are the criterion standard in craniofacial reconstruction for bony defects involving the craniofacial skeleton. The authors have previously demonstrated that graft microarchitecture is the major determinant of volume maintenance for both inlay and onlay bone grafts following transplantation. This study performs a head-to-head quantitative analysis of volume maintenance between inlay and onlay bone grafts in the craniofacial skeleton using a rabbit model to comparatively determine their resorptive kinetics over time. Methods Fifty rabbits were divided randomly into six experimental groups: 3-week inlay, 3-week onlay, 8-week inlay, 8-week onlay, 16-week inlay, and 16-week onlay. Cortical bone from the lateral mandible and both cortical and cancellous bone from the ilium were harvested from each animal and placed either in or on the cranium. All bone grafts underwent micro–computed tomographic analysis at 3, 8, and 16 weeks. Results All bone graft types in the inlay position increased their volume over time, with the greatest increase in endochondral cancellous bone. All bone graft types in the onlay position decreased their volume over time, with the greatest decrease in endochondral cancellous bone. Inlay bone grafts demonstrated increased volume compared with onlay bone grafts of identical embryologic origin and microarchitecture at all time points (p < 0.05). Conclusions Inlay bone grafts, irrespective of their embryologic origin, consistently display less resorption over time compared with onlay bone grafts in the craniofacial skeleton. Both inlay and onlay bone grafts are driven by the local mechanical environment to recapitulate the recipient bed. PMID:23629083

  12. Association between mean platelet volume and bone mineral density in postmenopausal women

    PubMed Central

    Aypak, Cenk; Türedi, Özlem; Bircan, Mustafa A.; Civelek, Gul M.; Araz, Mine

    2016-01-01

    [Purpose] Osteoporosis is an inflammatory disease, and platelets play a critical role in bone remodeling. Mean platelet volume has been shown to be influenced by inflammation. Our aim was to evaluate the relationship between mean platelet volume and bone mineral density in postmenopausal women. [Subjects and Methods] The records of female patients who had been referred to a tertiary hospital for bone mineral density analysis were retrospectively reviewed. [Results] A total of 175 patients (mean age: 61.3 ± 9.0 years) were enrolled. Overall, 72% (126/175) of patients met the criteria for osteoporosis. Mean platelet volume was found to be inversely correlated with body mass index. There was a significant positive correlation between mean platelet volume and femoral neck bone mineral density in our normal weight osteoporotic group, whereas there was a significant negative correlation in our overweight-obese osteoporotic group. The negative correlation between mean platelet volume and femoral neck bone mineral density in the overweight-obese osteoporotic group persisted after adjustment for confounding factors. Multivariate analyses revealed that mean platelet volume was significantly associated with femoral neck bone mineral density in osteoporotic patients in both our normal weight and overweight-obese groups. [Conclusion] Regardless of mechanisms, mean platelet volume might be used as a biomarker for osteoporosis in clinical settings. PMID:27390409

  13. Adequate dietary calcium restores vertebral trabecular bone microarchitecture and strength and improves femur calcium concentration following calcium depletion in young female rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To determine whether dietary calcium deficiency during adolescence permanently reduces lifetime potential to attain peak bone mass and strength, female Sprague-Dawley rats were separated into groups (n=10) and fed an AIN-93G-based diet containing 20% (1000 mg Ca/kg) of the calcium requirement from w...

  14. Spatial resolution and measurement uncertainty of strains in bone and bone-cement interface using digital volume correlation.

    PubMed

    Zhu, Ming-Liang; Zhang, Qing-Hang; Lupton, Colin; Tong, Jie

    2016-04-01

    The measurement uncertainty of strains has been assessed in a bone analogue (sawbone), bovine trabecular bone and bone-cement interface specimens under zero load using the Digital Volume Correlation (DVC) method. The effects of sub-volume size, sample constraint and preload on the measured strain uncertainty have been examined. There is generally a trade-off between the measurement uncertainty and the spatial resolution. Suitable sub-volume sizes have been be selected based on a compromise between the measurement uncertainty and the spatial resolution of the cases considered. A ratio of sub-volume size to a microstructure characteristic (Tb.Sp) was introduced to reflect a suitable spatial resolution, and the measurement uncertainty associated was assessed. Specifically, ratios between 1.6 and 4 appear to give rise to standard deviations in the measured strains between 166 and 620 με in all the cases considered, which would seem to suffice for strain analysis in pre as well as post yield loading regimes. A microscale finite element (μFE) model was built from the CT images of the sawbone, and the results from the μFE model and a continuum FE model were compared with those from the DVC. The strain results were found to differ significantly between the two methods at tissue level, consistent in trend with the results found in human bones, indicating mainly a limitation of the current DVC method in mapping strains at this level. PMID:26741534

  15. Mecp2 Deficiency Decreases Bone Formation and Reduces Bone Volume in a Rodent Model of Rett Syndrome

    PubMed Central

    O’Connor, R.D.; Zayzafoon, M.; Farach-Carson, M.C.; Schanen, N.C.

    2009-01-01

    Rett Syndrome (RTT), a neurological disorder characterized by neurological impairment and a high frequency of osteopenia which often manifests early in childhood, most often is caused by inactivating mutations in the X-linked gene encoding a regulator of epigenetic gene expression, methyl CpG binding protein, MeCP2. Clinical data show that, along with neurological defects, females with RTT frequently have marked decreases in Bone Mineral Density (BMD) beyond that expected from disuse atrophy. To investigate the relationship between loss of Mecp2 and reduced BMD, we used a Mecp2 null mouse model, Mecp2−/yBIRD, for our histological and biochemical studies. Mecp2−/yBIRD mice have significantly shorter femurs and an overall reduced skeletal size compared to wild-type mice by post-natal day 60 (P60). Histological and histomorphometric studies identified growth plate abnormalities as well as decreased cortical and trabecular bone in P21 and especially in P60 Mecp2−/yBIRD mice. Dynamic histomorphometry revealed decreased Mineral Apposition Rates (MAR) in Mecp2 null femoral trabecular bone as well as in calvarial bone samples. While changes in MAR of cortical bone were not significant, loss of Mecp2 significantly reduced cortical, trabecular and calvarial bone volume compared with age-matched wild-type animals. These differences indicate that Mecp2 deficiency leads to osteoblast dysfunction, which translates into reduced osteoid deposition accounting for the reduced bone volume phenotype. While individual variations were observed in OPG and Rankl concentrations, molar ratios of OPG:Rankl at P21 and P60 were comparable between wild-type and Mecp2−/yBIRD mice and showed a consistent excess of OPG. In tibial sections, TRAP staining demonstrated equivalent osteoclast number per bone surface measurements between wild-type and null animals. Our work with a Mecp2 null mouse model suggests epigenetic regulation of bone in the Mecp2−/yBIRD mice which is associated with

  16. The Volume Behavior of Autogenous Iliac Bone Grafts After Sinus Floor Elevation: A Clinical Pilot Study.

    PubMed

    Gerressen, Marcus; Riediger, Dieter; Hilgers, Ralf-Dieter; Hölzle, Frank; Noroozi, Nelson; Ghassemi, Alireza

    2015-06-01

    Iliac crest is still regarded as one of the most viable source of autogenous graft materials for extensive sinus floor elevation. Three-dimensional resorption behavior has to be taken into account in anticipation of the subsequent insertion of dental implants. We performed 3-dimensional volume measurements of the inserted bone transplants in 11 patients (6 women and 5 men; mean age = 2.3 years) who underwent bilateral sinus floor elevation with autogenous iliac crest grafts. In order to determine the respective bone graft volumes, cone-beam computerized tomography studies of the maxillary sinuses were carried out directly after the operation (T0), as well as 3 months (T1) and 6 months (T2) postoperatively. The acquired DICOM (Digital Imaging and Communications in Medicine) data sets were evaluated using suitable analysis software. We evaluated statistical significance of graft volumes changes using a linear mixed model with the grouping factors for time, age, side, and sex with a significance level of P = .05. 38.9% of the initial bone graft volume, which amounted to 4.2 cm(3), was resorbed until T1. At T2, the average volume again decreased significantly by 18.9 % to finally reach 1.8 cm(3). The results show neither age nor side dependency and apply equally to both sexes. Without functional load, iliac bone grafts feature low-volume stability in sinus-augmentation surgery. Further clinical and animal studies should be done to detect the optimal timing for implant placement. PMID:24303797

  17. Overexpression of BCLXL in Osteoblasts Inhibits Osteoblast Apoptosis and Increases Bone Volume and Strength.

    PubMed

    Moriishi, Takeshi; Fukuyama, Ryo; Miyazaki, Toshihiro; Furuichi, Tatsuya; Ito, Masako; Komori, Toshihisa

    2016-07-01

    The Bcl2 family proteins, Bcl2 and BclXL, suppress apoptosis by preventing the release of caspase activators from mitochondria through the inhibition of Bax subfamily proteins. We reported that BCL2 overexpression in osteoblasts using the 2.3 kb Col1a1 promoter increased osteoblast proliferation, failed to reduce osteoblast apoptosis, inhibited osteoblast maturation, and reduced the number of osteocyte processes, leading to massive osteocyte death. We generated BCLXL (BCL2L1) transgenic mice using the same promoter to investigate BCLXL functions in bone development and maintenance. Bone mineral density in the trabecular bone of femurs was increased, whereas that in the cortical bone was similar to that in wild-type mice. Osteocyte process formation was unaffected and bone structures were similar to those in wild-type mice. A micro-CT analysis showed that trabecular bone volume in femurs and vertebrae and the cortical thickness of femurs were increased. A dynamic bone histomorphometric analysis revealed that the mineralizing surface was larger in trabecular bone, and the bone-formation rate was increased in cortical bone. Serum osteocalcin but not TRAP5b was increased, BrdU-positive osteoblastic cell numbers were increased, TUNEL-positive osteoblastic cell numbers were reduced, and osteoblast marker gene expression was enhanced in BCLXL transgenic mice. The three-point bending test indicated that femurs were stronger in BCLXL transgenic mice than in wild-type mice. The frequency of TUNEL-positive primary osteoblasts was lower in BCLXL transgenic mice than in wild-type mice during cultivation, and osteoblast differentiation was enhanced but depended on cell density, indicating that enhanced differentiation was mainly owing to reduced apoptosis. Increased trabecular and cortical bone volumes were maintained during aging in male and female mice. These results indicate that BCLXL overexpression in osteoblasts increased the trabecular and cortical bone volumes with

  18. Measurement of bone cyst fluid volume using k-means clustering.

    PubMed

    Docquier, Pierre-Louis; Paul, Laurent; Menten, Renaud; Cartiaux, Olivier; Francq, Bernard; Banse, Xavier

    2009-12-01

    We designed a semiautomatic segmentation method to easily measure the volume of a bone cyst (simple or aneurysmal) from magnetic resonance imaging (MRI). This method only considers the fluid part of the cyst, even when there are several fluid intensities (fluid-fluid levels) or the cyst is multi-loculated. The nonhomogeneity phenomenon inherent in MRI was handled by a k-means clustering algorithm that classified all of the voxels corresponding to the cyst fluid as the same voxel intensity. Level-set segmentation was expanded into the whole cyst volume and the resulting segmented volume provided the measured cyst volume. The semiautomatic method was compared with the usual manual method (manual contour tracing) in terms of its ability to measure a known volume of water (gold standard) as well as the volume of 29 bone cysts. Both methods were equivalent with regards to the gold standard, but the semiautomatic method was more accurate. In terms of the experimental measurements, the semiautomatic method was more repeatable and reproducible, and less time-consuming and fastidious than the manual method. Our semiautomatic method uses only freeware and can be used routinely whenever measurement of a bone cyst volume is needed. PMID:19553051

  19. How do jet time, pressure and bone volume fraction influence the drilling depth when waterjet drilling in porcine bone?

    PubMed

    den Dunnen, Steven; Dankelman, Jenny; Kerkhoffs, Gino M M J; Tuijthof, Gabrielle J M

    2016-09-01

    Using water jets for orthopedic procedures that require bone drilling can be beneficial due to the absence of thermal damage and the always sharp cut. Previously, the influence of the water jet diameter and bone architectural properties on the drilling depth have been determined. To develop water jet instruments that can safely drill in orthopedic surgery, the impact of the two remaining primary factors were determined: the jet time (tjet [s]) and pressure (P [MPa]). To this end, 84 holes were drilled in porcine tali and femora with water jets using Ø 0.4mm nozzle. tjet was varied between 1, 3 and 5s and P between 50 and 70MPa. Drilling depths Lhole (mm), diameters Dhole (mm) and the volume of mineralized bone per unit volume (BV/TV) were determined with microCT scans. A non-linear regression analysis resulted in the predictive equation: Lhole= 0.22 * tjet(0.18) * (1.2-BV/TV) * (P-29) (R(2)=0.904). The established relation between the machine settings and drilling depth allows surgeons to adjust jet time and pressure for the patient׳s BV/TV to drill holes at a predetermined depth. For developers, the relation allows design decisions to be made that influence the dimensions, flexibility and accuracy of water jet instruments. For a pressure of 50MPa, the potential hole depth spread indicated by the 95% confidence interval is <1.6mm for all tested jet times. This maximum variance is smaller than the accuracy required for bone debridement treatments (2-4mm deep), which confirms that water jet drilling can be applied in orthopedic surgery to drill holes in bone with controlled depth. PMID:27288662

  20. The effect of a bisphosphonate on bone volume and eggshell structure in the hen.

    PubMed

    Thorp, B H; Wilson, S; Rennie, S; Solomon, S E

    1993-12-01

    Bisphosphonates, used in the prevention and treatment of osteoporosis, in man, can prevent bone loss in experimental models of osteoporosis in mammals. In egg-laying hens there is a high incidence of bone fractures which are due to osteoporosis. Alendronate, a bisphosphonate, was given to three groups of hens in mid-lay. Different doses of alendronate were given to each group and group 4 was a control. The birds were killed after 2 weeks of treatment. The hens receiving the highest dosage of alendronate (1 mg/kg every 2nd day) ceased laying and had reduced serum calcium concentrations. Lower dosages of alendronate (0.1 and 0.01 mg/kg every 2nd day) resulted in normal egg production and serum calcium concentrations. Egg shells with ultra-structural features indicative of reduced shell quality were produced by hens on the two higher dosages, but the egg shells from the controls and from the hens on the lowest dosage were considered normal. When alendronate was administered to hens in mid-lay there was no effect on trabecular bone volumes, but there was a reduction in mean medullary bone volume in some groups. In a second experiment, pullets were treated with alendronate (0.01 mg/kg twice a week) before the onset of lay. The pullets were killed after laying their first egg. In the pullets treated with alendronate, this protocol resulted in a significantly greater volume of trabecular (structural) bone at the onset of lay. PMID:18671052

  1. Noninvasive Femur Bone Volume Estimation Based on X-Ray Attenuation of a Single Radiographic Image and Medical Knowledge

    NASA Astrophysics Data System (ADS)

    Kiattisin, Supaporn; Chamnongthai, Kosin

    Bone Mineral Density (BMD) is an indicator of osteoporosis that is an increasingly serious disease, particularly for the elderly. To calculate BMD, we need to measure the volume of the femur in a noninvasive way. In this paper, we propose a noninvasive bone volume measurement method using x-ray attenuation on radiography and medical knowledge. The absolute thickness at one reference pixel and the relative thickness at all pixels of the bone in the x-ray image are used to calculate the volume and the BMD. First, the absolute bone thickness of one particular pixel is estimated by the known geometric shape of a specific bone part as medical knowledge. The relative bone thicknesses of all pixels are then calculated by x-ray attenuation of each pixel. Finally, given the absolute bone thickness of the reference pixel, the absolute bone thickness of all pixels is mapped. To evaluate the performance of the proposed method, experiments on 300 subjects were performed. We found that the method provides good estimations of real BMD values of femur bone. Estimates shows a high linear correlation of 0.96 between the volume Bone Mineral Density (vBMD) of CT-SCAN and computed vBMD (all P<0.001). The BMD results reveal 3.23% difference in volume from the BMD of CT-SCAN.

  2. Mean platelet volume as an indicator of platelet rejuvenation following bone-marrow transplantation. Master's thesis

    SciTech Connect

    Seanger, D.G.

    1986-07-01

    Thrombocytopenia of unpredictable duration and severity is an expected outcome of the radiation/chemotherapy protocols performed prior to bone-marrow transplantation. Serial evaluation of the platelet count and mean platelet volume of patients diagnosed with acute leukemia demonstrated the mean platelet volume to increase into reference limits 24 to 40 hours prior to a rise in the platelet count in those patients whose bone-marrow successfully responded to induction chemotherapy. Serial platelet counts and measurements of mean platelet volume were performed on 31 patients following bone marrow transplantation. Numerous platelet transfusions, together with sustained thrombocytopenia, inhibited accurate assessment of 29 of 31 patients. Two patients, however, demonstrated a rise in the mean platelet volume prior to an increase in the platelet count. Both of these patients received no platelet transfusions during the period preceding or following the rise in the platelet count. It was proposed that the serial evaluation of the mean platelet volume may assist practitioners in the decision-making process of deciding whether platlet transfusions are required, or an increase in the number of circulating platelets is imminent. A decision not to transfuse would have the direct benefit of decreasing patient costs, in conjunction with eliminating a potential source for the development of an antibody against platelets.

  3. Fluid volume displacement at the oval and round windows with air and bone conduction stimulation

    NASA Astrophysics Data System (ADS)

    Stenfelt, Stefan; Hato, Naohito; Goode, Richard L.

    2004-02-01

    The fluids in the cochlea are normally considered incompressible, and the fluid volume displacement of the oval window (OW) and the round window (RW) should be equal and of opposite phase. However, other channels, such as the cochlear and vestibular aqueducts, may affect the fluid flow. To test if the OW and RW fluid flows are equal and of opposite phase, the volume displacement was assessed by multiple point measurement at the windows with a laser Doppler vibrometer. This was done during air conduction (AC) stimulation in seven fresh human temporal bones, and with bone conduction (BC) stimulation in eight temporal bones and one human cadaver head. With AC stimulation, the average volume displacement of the two windows is within 3 dB, and the phase difference is close to 180° for the frequency range 0.1 to 10 kHz. With BC stimulation, the average volume displacement difference between the two windows is greater: below 2 kHz, the volume displacement at the RW is 5 to 15 dB greater than at the OW and above 2 kHz more fluid is displaced at the OW. With BC stimulation, lesions at the OW caused only minor changes of the fluid flow at the RW.

  4. Solid volume fraction estimation of bone:marrow replica models using ultrasound transit time spectroscopy.

    PubMed

    Wille, Marie-Luise; Langton, Christian M

    2016-02-01

    The acceptance of broadband ultrasound attenuation (BUA) for the assessment of osteoporosis suffers from a limited understanding of both ultrasound wave propagation through cancellous bone and its exact dependence upon the material and structural properties. It has recently been proposed that ultrasound wave propagation in cancellous bone may be described by a concept of parallel sonic rays; the transit time of each ray defined by the proportion of bone and marrow propagated. A Transit Time Spectrum (TTS) describes the proportion of sonic rays having a particular transit time, effectively describing the lateral inhomogeneity of transit times over the surface aperture of the receive ultrasound transducer. The aim of this study was to test the hypothesis that the solid volume fraction (SVF) of simplified bone:marrow replica models may be reliably estimated from the corresponding ultrasound transit time spectrum. Transit time spectra were derived via digital deconvolution of the experimentally measured input and output ultrasonic signals, and compared to predicted TTS based on the parallel sonic ray concept, demonstrating agreement in both position and amplitude of spectral peaks. Solid volume fraction was calculated from the TTS; agreement between true (geometric calculation) with predicted (computer simulation) and experimentally-derived values were R(2)=99.9% and R(2)=97.3% respectively. It is therefore envisaged that ultrasound transit time spectroscopy (UTTS) offers the potential to reliably estimate bone mineral density and hence the established T-score parameter for clinical osteoporosis assessment. PMID:26455950

  5. Genetic and Hormonal Control of Bone Volume, Architecture, and Remodeling in XXY Mice

    PubMed Central

    Liu, Peter Y; Kalak, Robert; Lue, YanHe; Jia, Yue; Erkkila, Krista; Zhou, Hong; Seibel, Markus J; Wang, Christina; Swerdloff, Ronald S; Dunstan, Colin R

    2010-01-01

    Klinefelter syndrome is the most common chromosomal aneuploidy in men (XXY karyotype, 1 in 600 live births) and results in testicular (infertility and androgen deficiency) and nontesticular (cognitive impairment and osteoporosis) deficits. The extent to which skeletal changes are due to testosterone deficiency or arise directly from gene overdosage cannot be determined easily in humans. To answer this, we generated XXY mice through a four-generation breeding scheme. Eight intact XXY and 9 XY littermate controls and 8 castrated XXY mice and 8 castrated XY littermate controls were euthanized at 1 year of age. Castration occurred 6 months prior to killing. A third group of 9 XXY and 11 XY littermates were castrated and simultaneously implanted with a 1-cm Silastic testosterone capsule 8 weeks prior to sacrifice. Tibias were harvested from all three groups and examined by micro–computed tomography and histomorphometry. Blood testosterone concentration was assayed by radioimmunoassay. Compared with intact XY controls, intact androgen-deficient XXY mice had lower bone volume (6.8% ± 1.2% versus8.8% ± 1.7%, mean ± SD, p = .01) and thinner trabeculae (50 ± 4 µm versus 57 ± 5 µm, p = .007). Trabecular separation (270 ± 20 µm versus 270 ± 20 µm) or osteoclast number relative to bone surface (2.4 ± 1.0/mm2 versus 2.7 ± 1.5/mm2) did not differ significantly. Testosterone-replaced XXY mice continued to show lower bone volume (5.5% ± 2.4% versus 8.1% ± 3.5%, p = .026). They also exhibited greater trabecular separation (380 ± 69 µm versus 324 ± 62 µm, p = .040) but equivalent blood testosterone concentrations (6.3 ± 1.8 ng/mL versus 8.2 ± 4.2 ng/mL, p = .28) compared with testosterone-replaced XY littermates. In contrast, castration alone drastically decreased bone volume (p < .001), trabecular thickness (p = .05), and trabecular separation (p < .01) to such a great extent that differences between XXY and XY mice were undetectable. In conclusion, XXY mice

  6. Scaling relations between bone volume and bone structure as found using 3D µCT images of the trabecular bone taken from different skeletal sites

    NASA Astrophysics Data System (ADS)

    Raeth, Christoph; Müller, Dirk; Sidorenko, Irina; Monetti, Roberto; Eckstein, Felix; Matsuura, Maiko; Lochmüller, Eva-Maria; Zysset, Philippe K.; Bauer, Jan

    2010-03-01

    According to Wolff's law bone remodels in response to the mechanical stresses it experiences so as to produce a minimal-weight structure that is adapted to its applied stresses. Here, we investigate the relations between bone volume and structure for the trabecular bone using 3D μCT images taken from different skeletal sites in vitro, namely from the distal radii (96 specimens), thoracic (73 specimens) and lumbar vertebrae (78 specimens). We determine the local structure of the trabecular network by calculating isotropic and anisotropic scaling indices (α, αz). These measures have been proven to be able to discriminate rod- from sheet-like structures and to quantify the alignment of structures with respect to a preferential direction as given by the direction of the external force. Comparing global structure measures derived from the scaling indices (mean, standard deviation) with the bone mass (BV/TV) we find that all correlations obey very accurately power laws with scaling exponents of 0.14, 0.12, 0.15 (<α>~), -0.2, -017, -0.17 (σ(αz)), 0.09, 0.05, 0.07 (<~αz>~) and -0.20, -0.11 ,-0.13 (σ(αz)) distal radius, thoracic vertebra and lumbar vertebra respectively. Thus, these relations turn out to be site-independent, albeit the mechanical stresses to which the bones of the forearm and the spine are exposed, are quite different. The similar alignment might not be in agreement with a universal validity of Wolff's law. On the other hand, such universal power law relations may allow to develop additional diagnostic means to better assess healthy and osteoporotic bone.

  7. Bone marrow lesion volume reduction is not associated with improvement of other periarticular bone measures: data from the Osteoarthritis Initiative

    PubMed Central

    2013-01-01

    Introduction We evaluated the associations between bone marrow lesion (BML) volume change and changes in periarticular bone mineral density (paBMD) as well as subchondral sclerosis to determine whether BML change is associated with other local bone changes. Methods The convenience sample comprised participants in the Osteoarthritis Initiative (OAI) with weight-bearing posterior-anterior knee radiographs and magnetic resonance images (MRIs) at the 24- and 48-month visits and dual-energy x-ray absorptiometry (DXA) at the 30-/36-month and 48-month visits. The right knee was assessed unless contraindicated for MRI. We used knee DXA scans to measure medial tibia paBMD and medial/lateral paBMD ratio (M:L paBMD). Knee radiographs were scored for sclerosis (grades 0 to 3) in the medial tibia. Two raters determined BML volume on sagittal fat-suppressed MRI by using a semiautomated segmentation method. To focus on knees with only medial tibia BML changes, knees with lateral tibial BMLs were excluded. Medial tibial BML volume change was classified into three groups: BML regression (lowest quartile of medial tibial BML volume change), no-to-minimal change (middle two quartiles), and BML progression (highest quartile). We used proportional odds logistic regression models to evaluate the association between quartiles of changes in medial paBMD or M:L paBMD ratio, as outcomes, and BML volume change. Results The sample (n = 308) included 163 (53%) female subjects, 212 (69%) knees with radiographic osteoarthritis, and participants with a mean age of 63.8 ± 9.3 years and mean body mass index of 29.8 ± 4.7 kg/m2. We found an association between greater increases in medial tibia paBMD and BML regression (OR = 1.7 (95% confidence interval (CI) = 1.1 to 2.8)) and a similar trend for BML progression (OR = 1.6 (95% CI = 1.0 to 2.6]). We also detected associations between greater increase in M:L paBMD and BML regression (OR = 1.6 (95% CI = 1.0 to 2

  8. Optimal sample volumes of human trabecular bone in μCT analysis within vertebral body and femoral head

    PubMed Central

    Wen, Xin-Xin; Zong, Chun-Lin; Xu, Chao; Ma, Xiang-Yu; Wang, Fa-Qi; Feng, Ya-Fei; Yan, Ya-Bo; Lei, Wei

    2015-01-01

    Trabecular bones of different skeletal sites have different bone morphologies. How to select an appropriate volume of region of interest (ROI) to reflect the microarchitecture of trabecular bone in different skeletal sites was an interesting problem. Therefore, in this study, the optimal volumes of ROI within vertebral body and femoral head, and if the relationships between volumes of ROI and microarchitectural parameters were affected by trabecular bone morphology were studied. Within vertebral body and femoral head, different cubic volumes of ROI (from (1 mm)3 to (20 mm)3) were set to compare with control groups(whole volume of trabecular bone). Five microarchitectural parameters (BV/TV, Tb.N, Tb.Th, Tb.Sp, and BS/BV) were obtained. Nonlinear curve fitting functions were used to explore the relationships between the microarchitectural parameters and the volumes of ROI. The volumes of ROI could affect the microarchitectural parameters when the volume was smaller than (8 mm)3 within the vertebral body and smaller than (13 mm)3 within the femoral head. As the volume increased, the variable tendencies of BV/TV, Tb.N, and Tb.Sp were different between these two skeletal sites. The curve fitting functions between these two sites were also different. The relationships between volumes of ROI and microarchitectural parameters were affected by the different trabecular bone morphologies within lumbar vertebral body and femoral head. When depicting the microarchitecture of human trabecular bone within lumbar vertebral body and femoral head, the volume of ROI would be larger than (8 mm)3 and (13 mm)3. PMID:26770381

  9. The effects of external beam irradiation on the growth of flat bones in children: Modeling a dose-volume effect

    SciTech Connect

    Krasin, Matthew J. . E-mail: mathew.krasin@stjude.org; Xiong Xiaoping; Wu Shengjie; Merchant, Thomas E.

    2005-08-01

    Purpose: To model the effects of external beam irradiation on the developing flat bones of pediatric patients undergoing radiation therapy (RT) for tumors involving the musculoskeletal system. Methods and Materials: Patients with image-guided RT plans including areas adjacent to facial or pelvic flat bones underwent retrospective contouring of nontumor involved flat bones ipsilateral and contralateral to the treatment side. Radiation dose-volume information and bone volume data (initial and the most recent follow-up) were analyzed in 15 paired flat bones from 10 patients (ages 1.0-17.0 years). The models to predict bone growth after completion of RT (v {sub post}) were based on initial bone volume (v {sub pre}), the patient's age, time to follow-up (t), and the dose-volume parameter (v{sub Int35+} ). Results: We developed a dose effects model as follows: Log (v{sub post} / v{sub pre} ) = {beta}{sub time}t + {beta}{sub agegroup}t + {beta}{sub dose}t v{sub Int35} . The dose-volume parameter v{sub Int35} predicted significantly for alterations in growth in younger patients, but not for older patients. The predictability of the fitted model for relative change in bone growth improved in the younger age group with the addition of the dose-volume term v{sub Int35} (correlation coefficient of r = 0.5510 to r = 0.6760 with the addition v{sub Int35} ). Conclusions: Our model accurately predicted flat bone growth and is notable for the inclusion of radiation dose-volume information, which is now available in the image-guided RT era. Further refinement of this model in a prospective patient population is underway.

  10. Hyoid bone development: An assessment of optimal CT scanner parameters and 3D volume rendering techniques

    PubMed Central

    Cotter, Meghan M.; Whyms, Brian J.; Kelly, Michael P.; Doherty, Benjamin M.; Gentry, Lindell R.; Bersu, Edward T.; Vorperian, Houri K.

    2015-01-01

    The hyoid bone anchors and supports the vocal tract. Its complex shape is best studied in three dimensions, but it is difficult to capture on computed tomography (CT) images and three-dimensional volume renderings. The goal of this study was to determine the optimal CT scanning and rendering parameters to accurately measure the growth and developmental anatomy of the hyoid and to determine whether it is feasible and necessary to use these parameters in the measurement of hyoids from in vivo CT scans. Direct linear and volumetric measurements of skeletonized hyoid bone specimens were compared to corresponding CT images to determine the most accurate scanning parameters and three-dimensional rendering techniques. A pilot study was undertaken using in vivo scans from a retrospective CT database to determine feasibility of quantifying hyoid growth. Scanning parameters and rendering technique affected accuracy of measurements. Most linear CT measurements were within 10% of direct measurements; however, volume was overestimated when CT scans were acquired with a slice thickness greater than 1.25 mm. Slice-by-slice thresholding of hyoid images decreased volume overestimation. The pilot study revealed that the linear measurements tested correlate with age. A fine-tuned rendering approach applied to small slice thickness CT scans produces the most accurate measurements of hyoid bones. However, linear measurements can be accurately assessed from in vivo CT scans at a larger slice thickness. Such findings imply that investigation into the growth and development of the hyoid bone, and the vocal tract as a whole, can now be performed using these techniques. PMID:25810349

  11. Strontium increases vertebral bone volume in rats at a low dose that does not induce detectable mineralization defect.

    PubMed

    Grynpas, M D; Hamilton, E; Cheung, R; Tsouderos, Y; Deloffre, P; Hott, M; Marie, P J

    1996-03-01

    Low doses of strontium and fluoride were shown to increase bone formation and trabecular bone density in rodents. To assess whether strontium or fluoride affect the quality of the mineral at doses known to increase bone density, we have determined the effects of low doses of strontium and fluoride on bone formation and bone mineral characteristics in rats. Adult rats were given strontium alone (0.20%), fluoride alone (1 mg/kg per day), or the combined treatment for 8 weeks. Strontium levels in serum and femur were similar in groups treated with strontium alone or in combination, being about 5% of calcium levels. Biochemical and neutron activation analyses in femur showed that calcium and magnesium contents did not differ in the four group of rats, suggesting that strontium was incorporated in the apatite lattice of the bone minerals in the strontium-treated rats. The mineralized bone volume was significantly increased by 17% in the strontium-treated group, by 20% in the fluoride-treated group, and by 19% in rats given with the combined treatment. This was associated with increased osteoid surface, osteoblast surface, and double tetracycline labeled surfaces in the strontium-treated and fluoride-treated groups, showing that the number of bone forming sites was increased. However, the mineral apposition rate, the osteoid thickness, and the mineralization lag time were similar in controls and treated groups, reflecting the lack of deleterious effects of low doses of strontium and fluoride on bone mineralization. The density fractionation analysis measured in the femur also showed that neither strontium, nor fluoride at the low doses used, significantly altered the mineralization profile. The results indicate that treatment with low doses of strontium or fluoride increase the number of bone forming sites and vertebral bone volume in rats, but does not have detectable adverse effects on the mineral profile, bone mineral chemistry or bone matrix mineralization. PMID

  12. Variation of bone layer thicknesses and trabecular volume fraction in the adult male human calvarium.

    PubMed

    Boruah, Sourabh; Paskoff, Glenn R; Shender, Barry S; Subit, Damien L; Salzar, Robert S; Crandall, Jeff R

    2015-08-01

    The human calvarium is a sandwich structure with two dense layers of cortical bone separated by porous cancellous bone. The variation of the three dimensional geometry, including the layer thicknesses and the volume fraction of the cancellous layer across the population, is unavailable in the current literature. This information is of particular importance to mathematical models of the human head used to simulate mechanical response. Although the target geometry for these models is the median geometry of the population, the best attempt so far has been the scaling of a unique geometry based on a few median anthropometric measurements of the head. However, this method does not represent the median geometry. This paper reports the average three dimensional geometry of the calvarium from X-ray computed tomography (CT) imaging and layer thickness and trabecular volume fraction from micro CT (μCT) imaging of ten adult male post-mortem human surrogates (PMHS). Skull bone samples have been obtained and μCT imaging was done at a resolution of 30 μm. Monte Carlo simulation was done to estimate the variance in these measurements due to the uncertainty in image segmentation. The layer thickness data has been averaged over areas of 5mm(2). The outer cortical layer was found to be significantly (p < 0.01; Student's t test) thicker than the inner layer (median of thickness ratio 1.68). Although there was significant location to location difference in all the layer thicknesses and volume fraction measurements, there was no trend. Average distribution and the variance of these metrics on the calvarium have been shown. The findings have been reported as colormaps on a 2D projection of the cranial vault. PMID:25920690

  13. Multi-temporal MRI carpal bone volumes analysis by principal axes registration

    NASA Astrophysics Data System (ADS)

    Ferretti, Roberta; Dellepiane, Silvana

    2016-03-01

    In this paper, a principal axes registration technique is presented, with the relevant application to segmented volumes. The purpose of the proposed registration is to compare multi-temporal volumes of carpal bones from Magnetic Resonance Imaging (MRI) acquisitions. Starting from the study of the second-order moment matrix, the eigenvectors are calculated to allow the rotation of volumes with respect to reference axes. Then the volumes are spatially translated to become perfectly overlapped. A quantitative evaluation of the results obtained is carried out by computing classical indices from the confusion matrix, which depict similarity measures between the volumes of the same organ as extracted from MRI acquisitions executed at different moments. Within the medical field, the way a registration can be used to compare multi-temporal images is of great interest, since it provides the physician with a tool which allows a visual monitoring of a disease evolution. The segmentation method used herein is based on the graph theory and is a robust, unsupervised and parameters independent method. Patients affected by rheumatic diseases have been considered.

  14. A high volume extraction and purification method for recovering DNA from human bone.

    PubMed

    Marshall, Pamela L; Stoljarova, Monika; Schmedes, Sarah E; King, Jonathan L; Budowle, Bruce

    2014-09-01

    DNA recovery, purity and overall extraction efficiency of a protocol employing a novel silica-based column, Hi-Flow(®) (Generon Ltd., Maidenhead, UK), were compared with that of a standard organic DNA extraction methodology. The quantities of DNA recovered by each method were compared by real-time PCR and quality of DNA by STR typing using the PowerPlex(®) ESI 17 Pro System (Promega Corporation, Madison, WI) on DNA from 10 human bone samples. Overall, the Hi-Flow method recovered comparable quantities of DNA ranging from 0.8ng±1 to 900ng±159 of DNA compared with the organic method ranging from 0.5ng±0.9 to 855ng±156 of DNA. Complete profiles (17/17 loci tested) were obtained for at least one of three replicates for 3/10 samples using the Hi-Flow method and from 2/10 samples with the organic method. All remaining bone samples yielded partial profiles for all replicates with both methods. Compared with a standard organic DNA isolation method, the results indicated that the Hi-Flow method provided equal or improved recovery and quality of DNA without the harmful effects of organic extraction. Moreover, larger extraction volumes (up to 20mL) can be employed with the Hi-Flow method which enabled more bone sample to be extracted at one time. PMID:24997320

  15. Bone Fractures Following External Beam Radiotherapy and Limb-Preservation Surgery for Lower Extremity Soft Tissue Sarcoma: Relationship to Irradiated Bone Length, Volume, Tumor Location and Dose

    SciTech Connect

    Dickie, Colleen I.; Parent, Amy L.; Griffin, Anthony M.; Fung, Sharon; Chung, Peter W.M.; Catton, Charles N.; Ferguson, Peter C.; Wunder, Jay S.; Bell, Robert S.; Sharpe, Michael B.; O'Sullivan, Brian

    2009-11-15

    Purpose: To examine the relationship between tumor location, bone dose, and irradiated bone length on the development of radiation-induced fractures for lower extremity soft tissue sarcoma (LE-STS) patients treated with limb-sparing surgery and radiotherapy (RT). Methods and Materials: Of 691 LE-STS patients treated from 1989 to 2005, 31 patients developed radiation-induced fractures. Analysis was limited to 21 fracture patients (24 fractures) who were matched based on tumor size and location, age, beam arrangement, and mean total cumulative RT dose to a random sample of 53 nonfracture patients and compared for fracture risk factors. Mean dose to bone, RT field size (FS), maximum dose to a 2-cc volume of bone, and volume of bone irradiated to >=40 Gy (V40) were compared. Fracture site dose was determined by comparing radiographic images and surgical reports to fracture location on the dose distribution. Results: For fracture patients, mean dose to bone was 45 +- 8 Gy (mean dose at fracture site 59 +- 7 Gy), mean FS was 37 +- 8 cm, maximum dose was 64 +- 7 Gy, and V40 was 76 +- 17%, compared with 37 +- 11 Gy, 32 +- 9 cm, 59 +- 8 Gy, and 64 +- 22% for nonfracture patients. Differences in mean, maximum dose, and V40 were statistically significant (p = 0.01, p = 0.02, p = 0.01). Leg fractures were more common above the knee joint. Conclusions: The risk of radiation-induced fracture appears to be reduced if V40 <64%. Fracture incidence was lower when the mean dose to bone was <37 Gy or maximum dose anywhere along the length of bone was <59 Gy. There was a trend toward lower mean FS for nonfracture patients.

  16. Large volume inside the cage leading incomplete interbody bone fusion and residual back pain after posterior lumbar interbody fusion.

    PubMed

    Takeuchi, Mikinobu; Kamiya, Mitsuhiro; Wakao, Norimitsu; Hirasawa, Atsuhiko; Kawanami, Katsuhisa; Osuka, Koji; Takayasu, Masakazu

    2015-07-01

    The purpose of this study is to compare intervertebral bone fusion and clinical outcomes in L4-5 posterior lumbar interbody fusion (PLIF) using the same posterior instrumentation with four combinations of one of three types of interbody cage with one of two bone grafts, iliac and local or only local. In 67 patients who underwent L4-5 PLIF, 19 patients had the Brantigan cage and iliac and local bone graft, 18 with the TELAMON C cage and iliac and local bone graft, 16 with the TELAMON C cage and local bone graft (TL), and 14 with the OIC PEEK cage and local bone graft. Clinical assessments were based on Japanese Orthopaedic Association (JOA) scores and on the visual analogue scale (VAS). The bone fusion assessments were based on radiography and CT scans according to the Brantigan, Steffee, and Fraser criteria. More than 2 years after surgery, these assessments were made. In the results, the fusion outcome for the group receiving TL was significantly less than those for the other three groups. In TL, multivariate logistic regression analysis showed that the inside volume of the cage of ≥2.0 mL was the only significant factor for incomplete fusion. Moreover, the VAS (low back pain) score was significantly higher for TL than for the other three groups. In conclusions, we believe that the large volume inside the cage (≥2.0 mL) with local bone graft may lead incomplete interbody bone fusion and residual postsurgical low back pain after PLIF. PMID:25666390

  17. Relationship between trabecular texture features of CT images and an amount of bone cement volume injection in percutaneous vertebroplasty

    NASA Astrophysics Data System (ADS)

    Tack, Gye Rae; Choi, Hyung Guen; Shin, Kyu-Chul; Lee, Sung J.

    2001-06-01

    Percutaneous vertebroplasty is a surgical procedure that was introduced for the treatment of compression fracture of the vertebrae. This procedure includes puncturing vertebrae and filling with polymethylmethacrylate (PMMA). Recent studies have shown that the procedure could provide structural reinforcement for the osteoporotic vertebrae while being minimally invasive and safe with immediate pain relief. However, treatment failures due to disproportionate PMMA volume injection have been reported as one of complications in vertebroplasty. It is believed that control of PMMA volume is one of the most critical factors that can reduce the incidence of complications. In this study, appropriate amount of PMMA volume was assessed based on the imaging data of a given patient under the following hypotheses: (1) a relationship can be drawn between the volume of PMMA injection and textural features of the trabecular bone in preoperative CT images and (2) the volume of PMMA injection can be estimated based on 3D reconstruction of postoperative CT images. Gray-level run length analysis was used to determine the textural features of the trabecular bone. The width of trabecular (T-texture) and the width of intertrabecular spaces (I-texture) were calculated. The correlation between PMMA volume and textural features of patient's CT images was also examined to evaluate the appropriate PMMA amount. Results indicated that there was a strong correlation between the actual PMMA injection volume and the area of the intertrabecular space and that of trabecular bone calculated from the CT image (correlation coefficient, requals0.96 and requals-0.95, respectively). T- texture (requals-0.93) did correlate better with the actual PMMA volume more than the I-texture (requals0.57). Therefore, it was demonstrated that appropriate PMMA injection volume could be predicted based on the textural analysis for better clinical management of the osteoporotic spine.

  18. Sex determination using discriminant analysis of upper and lower extremity bones: New approach using the volume and surface area of digital model.

    PubMed

    Lee, U-Young; Kim, In-Beom; Kwak, Dai-Soon

    2015-08-01

    This study used 110 CT images taken from donated Korean cadavers to create 3-D models of the following upper and lower limb bones: the clavicle, scapula, humerus, radius, ulna, hip bone (os coxa), femur, patella (knee cap), tibia, talus, and calcaneus. In addition, the bone volume and surface area were calculated to determine sex differences using discriminant analysis. Significant sex differences were found in all bones with respect to volume and surface area (p<0.01). The order of volume was the same in females and males (femur>hip bone>tibia>humerus>scapula), although the order of surface area was different. The largest surface area in men was the femur and in women was the hip bone (p<0.01). An interesting finding of this study was that the ulna is the bone with the highest accuracy for sex determination (94%). When using the surface area of multiple bones, the maximum accuracy (99.4%) was achieved. The equation was as follows: (discriminant equation of surface area; female<0bone+0.091×patella+(-0.052)×fibula+0.043×talus-11.548. These results show that bone volume and surface area of extremity bones can be used for sex determination. PMID:26117502

  19. Differential Effects of Dabigatran and Warfarin on Bone Volume and Structure in Rats with Normal Renal Function

    PubMed Central

    Fusaro, Maria; Dalle Carbonare, Luca; Dusso, Adriana; Arcidiacono, Maria Vittoria; Valenti, Maria Teresa; Aghi, Andrea; Pasho, Sabina; Gallieni, Maurizio

    2015-01-01

    Background Warfarin, a widely used anticoagulant, is a vitamin K antagonist impairing the activity of vitamin K-dependent Bone Gla Protein (BGP or Osteocalcin) and Matrix Gla Protein (MGP). Because dabigatran, a new anticoagulant, has no effect on vitamin K metabolism, the aim of this study was to compare the impact of warfarin and dabigatran administration on bone structure and vascular calcification. Methods Rats with normal renal function received for 6 weeks warfarin, dabigatran or placebo. Bone was evaluated immuno-histochemically and hystomorphometrically after double labelling with declomycin and calcein. Aorta and iliac arteries were examined histologically. Results Histomorphometric analysis of femur and vertebrae showed significantly decreased bone volume and increased trabecular separation in rats treated with warfarin. Vertebra analysis showed that the trabecular number was higher in dabigatran treated rats. Osteoblast activity and resorption parameters were similar among groups, except for maximum erosion depth, which was higher in warfarin treated rats, suggesting a higher osteoclastic activity. Therefore, warfarin treatment was also associated with higher bone formation rate/bone surface and activation frequency. Warfarin treatment may cause an increased bone turnover characterized by increased remodelling cycles, with stronger osteoclast activity compared to the other groups. There were no differences among experimental groups in calcium deposition either in aortic or iliac arteries. Conclusions These findings suggest for the first time that dabigatran has a better bone safety profile than warfarin, as warfarin treatment affects bone by reducing trabecular size and structure, increasing turnover and reducing mineralization. These differences could potentially result in a lower incidence of fractures in dabigatran treated patients. PMID:26241483

  20. Secondary alveolar bone grafting: our experience with olecranon bone graft.

    PubMed

    Nadal, Emmanuela; Sabás, Mariana; Dogliotti, Pedro; Espósito, Raquel

    2010-03-01

    Management of alveolar cleft has dramatically changed during the last century: secondary alveolar bone grafting is now an integral part of cleft palate and craniofacial center's protocols. The objectives of alveolar repair and bone grafting are as follows: providing a continuous and stable maxillary dental arch, closure of oronasal fistulae, adequate bone for tooth eruption or orthodontic movement, and nasal base support, improving facial aesthetic. Although cancellous iliac bone is the donor site selected more frequently, bone grafts harvested from different sites have been advocated to decrease donor site morbidity.The aim of this study was to propose and evaluate the use of olecranon as a donor site in 24 patients with secondary alveolar cleft. The graft is taken as a single piece to fit the alveolar cleft defect, and it includes periosteum and corticocancellous bone to improve early vascularization and greater volume maintenance. PMID:20186086

  1. Study of Different Involutive Changes in Bone Mineral Density Measured in Ward's Triangle and Trabecular Volume Measured in Iliac Crest in Relation to Age

    PubMed Central

    Castillo, RF; Gallegos, RF

    2015-01-01

    ABSTRACT Background: The ageing process causes changes in the bone structure, in bone mineral density, and musculoskeletal disorders. Aims: The purpose of this study is to evaluate and compare involutive changes in bone structure that occur in relation to age in men and women through the study of bone mineral density at the Ward's triangle and trabecular volume. Subjects and Methods: In this study, we analysed bone mineral density at Ward's triangle in 70 people (38 men and 32 women) and did a histomorphometric study of trabecular volume at the right iliac crest in 66 samples (42 males and 24 females) obtained from autopsies of court cases, aged between 13 and 83 years. Results: The results show significant correlations between measurements of bone mineral density, trabecular volume values and anthropometric measures of age, gender and body mass index. Conclusions: This study shows involutional changes that occur in the bone mineral density and Ward's triangle in the bone structure during the process of ageing. In addition, both weight and height have a great influence on bone mineral density and changes in bone that occur; and body mass index is a very important determinant of bone mineral density. PMID:26360671

  2. Relationship between sample volumes and modulus of human vertebral trabecular bone in micro-finite element analysis.

    PubMed

    Wen, Xin-Xin; Xu, Chao; Zong, Chun-Lin; Feng, Ya-Fei; Ma, Xiang-Yu; Wang, Fa-Qi; Yan, Ya-Bo; Lei, Wei

    2016-07-01

    Micro-finite element (μFE) models have been widely used to assess the biomechanical properties of trabecular bone. How to choose a proper sample volume of trabecular bone, which could predict the real bone biomechanical properties and reduce the calculation time, was an interesting problem. Therefore, the purpose of this study was to investigate the relationship between different sample volumes and apparent elastic modulus (E) calculated from μFE model. 5 Human lumbar vertebral bodies (L1-L5) were scanned by micro-CT. Cubic concentric samples of different lengths were constructed as the experimental groups and the largest possible volumes of interest (VOI) were constructed as the control group. A direct voxel-to-element approach was used to generate μFE models and steel layers were added to the superior and inferior surface to mimic axial compression tests. A 1% axial strain was prescribed to the top surface of the model to obtain the E values. ANOVA tests were performed to compare the E values from the different VOIs against that of the control group. Nonlinear function curve fitting was performed to study the relationship between volumes and E values. The larger cubic VOI included more nodes and elements, and more CPU times were needed for calculations. E values showed a descending tendency as the length of cubic VOI decreased. When the volume of VOI was smaller than (7.34mm(3)), E values were significantly different from the control group. The fit function showed that E values approached an asymptotic values with increasing length of VOI. Our study demonstrated that apparent elastic modulus calculated from μFE models were affected by the sample volumes. There was a descending tendency of E values as the length of cubic VOI decreased. Sample volume which was not smaller than (7.34mm(3)) was efficient enough and timesaving for the calculation of E. PMID:26999702

  3. Manipulation of Ovarian Function Significantly Influenced Trabecular and Cortical Bone Volume, Architecture and Density in Mice at Death

    PubMed Central

    Mason, Jeffrey B.; Terry, Boston C.; Merchant, Samer S.; Mason, Holly M.; Nazokkarmaher, Mahdi

    2015-01-01

    Previously, transplantation of ovaries from young, cycling mice into old, postreproductive-age mice increased life span and decreased cardiomyopathy at death. We anticipated that the same factors that increased life span and decreased cardiomyopathy could also influence the progression of orthopedic disease. At 11 months of age, prepubertally ovariectomized and ovary-intact mice (including reproductively cycling and acyclic mice) received new 60-day-old ovaries. At death, epiphyseal bone in the proximal tibia and the distal femur and mid-shaft tibial and femoral diaphyseal bone was analyzed with micro-computed tomography. For qualitative analysis of osteophytosis, we also included mineralized connective tissue within the stifle joint. Prepubertal ovariectomy had the greatest influence on bone volume, ovarian transplantation had the greatest influence on bone architecture and both treatments influenced bone density. Ovarian transplantation increased cortical, but not trabecular bone density and tended to increase osteophytosis and heterotopic mineralization, except in acyclic recipients. These effects may have been dictated by the timing of the treatments, with ovariectomy appearing to influence early development and ovarian transplantation limited to influencing only the postreproductive period. However, major differences observed between cycling, acyclic and ovariectomized recipients of new ovaries may have been, in part due to differences in the levels of hormone receptors present and the responsiveness of specific bone processes to hormone signaling. Changes that resulted from these treatments may represent a compensatory response to normal age-associated, negative, orthopedic changes. Alternatively, differences between treatments may simply be the 'preservation' of unblemished orthopedic conditions, prior to the influence of negative, age-associated effects. These findings may suggest that in women, tailoring hormone replacement therapy to the patient's current

  4. Bone Metabolism in Adolescents with Anorexia Nervosa

    PubMed Central

    Misra, Madhusmita; Klibanski, Anne

    2013-01-01

    Adolescents with anorexia nervosa (AN) are at risk for low bone mass at multiple sites, associated with decreased bone turnover. Bone microarchitecture is also affected, with a decrease in bone trabecular volume and trabecular thickness, and an increase in trabecular separation. The adolescent years are typically the time when marked increases occur in bone mass accrual towards the attainment of peak bone mass, an important determinant of bone health and fracture risk in later life. AN often begins in the adolescent years, and decreased rates of bone mass accrual at this critical time are therefore also concerning for deficits in peak bone mass. Factors contributing to low bone density and decreased rates of bone accrual include alterations in body composition such as low BMI and lean body mass, and hormonal alterations such as hypogonadism, a nutritionally acquired resistance to growth hormone and low levels of IGF-1, relative hypercortisolemia, low levels of leptin, and increased adiponectin (for fat mass) and peptide YY. Therapeutic strategies include optimizing weight and menstrual recovery, and adequate calcium and vitamin D replacement. Oral estrogen-progesterone combination pills are not effective in increasing bone density in adolescents with AN. RhIGF-1 increases levels of bone formation markers in the short-term, while long-term effects remain to be determined. Bisphosphonates act by decreasing bone resorption, and are not optimal for use in adolescents with AN, in whom the primary defect is low bone formation. PMID:21301203

  5. Low fatness, reduced fat intake and adequate plasmatic concentrations of LDL-cholesterol are associated with high bone mineral density in women: a cross-sectional study with control group

    PubMed Central

    2012-01-01

    Background Several parameters are associated with high bone mineral density (BMD), such as overweight, black background, intense physical activity (PA), greater calcium intake and some medications. The objectives are to evaluate the prevalence and the main aspects associated with high BMD in healthy women. Methods After reviewing the database of approximately 21,500 BMD scans performed in the metropolitan area of São Paulo, Brazil, from June 2005 to October 2010, high BMD (over 1400 g/cm2 at lumbar spine and/or above 1200 g/cm2 at femoral neck) was found in 421 exams. Exclusion criteria were age below 30 or above 60 years, black ethnicity, pregnant or obese women, disease and/or medications known to interfere with bone metabolism. A total of 40 women with high BMD were included and matched with 40 healthy women with normal BMD, paired to weight, age, skin color and menopausal status. Medical history, food intake and PA were assessed through validated questionnaires. Body composition was evaluated through a GE-Lunar DPX MD + bone densitometer. Radiography of the thoracic and lumbar spine was carried out to exclude degenerative alterations or fractures. Biochemical parameters included both lipid and hormonal profiles, along with mineral and bone metabolism. Statistical analysis included parametric and nonparametric tests and linear regression models. P < 0.05 was considered significant. Results The mean age was 50.9 (8.3) years. There was no significant difference between groups in relation to PA, smoking, intake of calcium and vitamin D, as well as laboratory tests, except serum C-telopeptide of type I collagen (s-CTX), which was lower in the high BMD group (p = 0.04). In the final model of multivariate regression, a lower fat intake and body fatness as well a better profile of LDL-cholesterol predicted almost 35% of high BMD in women. (adjusted R2 = 0.347; p < 0.001). In addition, greater amounts of lean mass and higher IGF-1 serum concentrations played a

  6. Measurement of lacunar bone strains and crack formation during tensile loading by digital volume correlation of second harmonic generation images.

    PubMed

    Wentzell, Scott; Nesbitt, Robert Sterling; Macione, James; Kotha, Shiva

    2016-07-01

    The maintenance of healthy bone tissue depends upon the ability of osteocytes to respond to mechanical cues on the cellular level. The combination of digital volume correlation and second harmonic generation microscopy offers the opportunity to investigate the mechanical microenvironment of intact bone on the scale of individual osteocytes. Adult human femurs were imaged under tensile loads of 5 and 15MPa and volumes of approximately 492×429×31μm(3) were analyzed, along with an image of a bone microcrack under the same loading conditions. Principal strains were significantly higher in three-dimensional digital volume correlation when compared to two-dimensional digital image correlation. The average maximum principal strain magnitude was 5.06-fold greater than the applied global strain, with peak strains of up to 23.14-fold over global strains measured at the borders of osteocyte lacunae. Finally, a microcrack that initiated at an osteocyte lacunae had its greatest tensile strain magnitudes at the crack expansion front in the direction of a second lacunae, but strain at the crack border was reduced to background strain magnitudes upon breaching the second lacunae. This serveed to demonstrate the role of lacunae in initiating, mediating and terminating microcrack growth. PMID:26807766

  7. Hyoid Bone Development: An Assessment Of Optimal CT Scanner Parameters and Three-Dimensional Volume Rendering Techniques.

    PubMed

    Cotter, Meghan M; Whyms, Brian J; Kelly, Michael P; Doherty, Benjamin M; Gentry, Lindell R; Bersu, Edward T; Vorperian, Houri K

    2015-08-01

    The hyoid bone anchors and supports the vocal tract. Its complex shape is best studied in three dimensions, but it is difficult to capture on computed tomography (CT) images and three-dimensional volume renderings. The goal of this study was to determine the optimal CT scanning and rendering parameters to accurately measure the growth and developmental anatomy of the hyoid and to determine whether it is feasible and necessary to use these parameters in the measurement of hyoids from in vivo CT scans. Direct linear and volumetric measurements of skeletonized hyoid bone specimens were compared with corresponding CT images to determine the most accurate scanning parameters and three-dimensional rendering techniques. A pilot study was undertaken using in vivo scans from a retrospective CT database to determine feasibility of quantifying hyoid growth. Scanning parameters and rendering technique affected accuracy of measurements. Most linear CT measurements were within 10% of direct measurements; however, volume was overestimated when CT scans were acquired with a slice thickness greater than 1.25 mm. Slice-by-slice thresholding of hyoid images decreased volume overestimation. The pilot study revealed that the linear measurements tested correlate with age. A fine-tuned rendering approach applied to small slice thickness CT scans produces the most accurate measurements of hyoid bones. However, linear measurements can be accurately assessed from in vivo CT scans at a larger slice thickness. Such findings imply that investigation into the growth and development of the hyoid bone, and the vocal tract as a whole, can now be performed using these techniques. PMID:25810349

  8. SU-E-T-143: Effect of X-Ray and Cone Beam CT Reconstruction Parameters On Estimation of Bone Volume of Mice Used in Aging Research

    SciTech Connect

    Russ, M; Pang, M; Troen, B; Rudin, S; Ionita, C

    2014-06-01

    Purpose: To investigate the variations in bone volume calculations in mice involved in aging research when changing cone beam micro-CT x-ray and reconstruction parameters. Methods: Mouse spines were placed on an indexed turn table that rotated 0.5° per projection and imaged by a self-built micro CT machine containing a CCD-based high-resolution x-ray detector. After the full 360° rotation data set of object images was obtained, a standard filtered back-projection cone beam reconstruction was performed. Four different kVp's between 40–70 kVp in 10kVp increments were selected. For each kVp two mAs settings were used. Each acquisition was reconstructed using two voxel sizes (12 and 25μm) and two step angles, 0.5° and 1°, respectively. A LabView program was written to determine the total bone volume contained in the mouse's total spine volume (bone plus gaps) as a measure of spine health. First, the user selected the desired 512×512 reconstruction to view the whole spine volume which was then used to select a gray-level threshold that allowed for viewing of the bone structure, then another threshold to include gaps. The program returned bone volume, bone × gap volume, and their ratio, BVF. Results: The calculated bone volume fractions were compared as a function of tube potential. Cases with 25μm slice thickness showed trials with lower kVp's had greater image contrast, which resulted in higher calculated bone volume fractions. Cases with 12μm reconstructed slice thickness were significantly noisier, and showed no clear maximum BVF. Conclusion: Using the projection images and reconstructions acquired from the micro CT, it can be shown that the micro-CT x-ray and reconstruction parameters significantly affect the total bone volume calculations. When comparing mice cohorts treated with different therapies researchers need to be aware of such details and use volumes which were acquired and processed in identical conditions.

  9. Mechanical Loading Synergistically Increases Trabecular Bone Volume and Improves Mechanical Properties in the Mouse when BMP Signaling Is Specifically Ablated in Osteoblasts

    PubMed Central

    Iura, Ayaka; McNerny, Erin Gatenby; Zhang, Yanshuai; Kamiya, Nobuhiro; Tantillo, Margaret; Lynch, Michelle; Kohn, David H.; Mishina, Yuji

    2015-01-01

    Bone homeostasis is affected by several factors, particularly mechanical loading and growth factor signaling pathways. There is overwhelming evidence to validate the importance of these signaling pathways, however, whether these signals work synergistically or independently to contribute to proper bone maintenance is poorly understood. Weight-bearing exercise increases mechanical load on the skeletal system and can improves bone quality. We previously reported that conditional knockout (cKO) of Bmpr1a, which encodes one of the type 1 receptors for Bone Morphogenetic Proteins (BMPs), in an osteoblast-specific manner increased trabecular bone mass by suppressing osteoclastogenesis. The cKO bones also showed increased cortical porosity, which is expected to impair bone mechanical properties. Here, we evaluated the impact of weight-bearing exercise on the cKO bone phenotype to understand interactions between mechanical loading and BMP signaling through BMPR1A. Male mice with disruption of Bmpr1a induced at 9 weeks of age, exercised 5 days per week on a motor-driven treadmill from 11 to 16 weeks of age. Trabecular bone volume in cKO tibia was further increased by exercise, whereas exercise did not affect the trabecular bone in the control genotype group. This finding was supported by decreased levels of osteoclasts in the cKO tibiae. The cortical porosity in the cKO bones showed a marginally significant decrease with exercise and approached normal levels. Exercise increased ductility and toughness in the cKO bones. Taken together, reduction in BMPR1A signaling may sensitize osteoblasts for mechanical loading to improve bone mechanical properties. PMID:26489086

  10. Cortical Bone Water Concentration: Dependence of MR Imaging Measures on Age and Pore Volume Fraction

    PubMed Central

    Li, Cheng; Seifert, Alan C.; Rad, Hamidreza Saligheh; Bhagat, Yusuf A.; Rajapakse, Chamith S.; Sun, Wenli; Lam, Shing Chun Benny

    2014-01-01

    Purpose To quantify bulk bone water to test the hypothesis that bone water concentration (BWC) is negatively correlated with bone mineral density (BMD) and is positively correlated with age, and to propose the suppression ratio (SR) (the ratio of signal amplitude without to that with long-T2 suppression) as a potentially stronger surrogate measure of porosity, which is evaluated ex vivo and in vivo. Materials and Methods Human subject studies were conducted in compliance with institutional review board and HIPAA regulations. Healthy men and women (n = 72; age range, 20–80 years) were examined with a hybrid radial ultrashort echo time magnetic resonance (MR) imaging sequence at 3.0 T, and BWC was determined in the tibial midshaft. In a subset of 40 female subjects, the SR was measured with a similar sequence. Cortical volumetric BMD (vBMD) was measured by means of peripheral quantitative computed tomography (CT). The method was validated against micro-CT–derived porosity in 13 donor human cortical bone specimens. Associations among parameters were evaluated by using standard statistical tools. Results BWC was positively correlated with age (r = 0.52; 95% confidence interval [CI]: 0.22, 0.73; P = .002) and negatively correlated with vBMD at the same location (r = −0.57; 95% CI: −0.76, −0.29; P < .001). Data were suggestive of stronger associations with SR (r = 0.64, 95% CI: 0.39, 0.81, P < .001 for age; r = −0.67, 95% CI: −0.82, −0.43, P < .001 for vBMD; P < .001 for both), indicating that SR may be a more direct measure of porosity. This interpretation was supported by ex vivo measurements showing SR to be strongly positively correlated with micro-CT porosity (r = 0.88; 95% CI: 0.64, 0.96; P < .001) and with age (r = 0.87; 95% CI: 0.62, 0.96; P < .001). Conclusion The MR imaging–derived SR may serve as a biomarker for cortical bone porosity that is potentially superior to BWC, but corroboration in larger cohorts is indicated. © RSNA, 2014 PMID

  11. Determining sex by bone volume from 3D images: discriminating analysis of the tali and radii in a contemporary Spanish reference collection.

    PubMed

    Ruiz Mediavilla, Elena; Perea Pérez, Bernardo; Labajo González, Elena; Sánchez Sánchez, José Antonio; Santiago Sáez, Andrés; Dorado Fernández, Enrique

    2012-07-01

    The discriminant power of bone volume for determining sex has not been possible to determine due to the difficulty in its calculation. At present, new advancements based on 3D technology make it possible to reproduce the bone digitally and calculate its volume using computerized tools, which opens up a new window to ascertaining the discriminant power of this variable. With this objective in mind, the tali and radii of 101 individuals (48 males and 53 females) of a contemporary Spanish reference collection (twentieth century) (EML 1) were scanned using the Picza 3D Laser Scanner. Calculated for the tali were total volume, the volume of the posterior region, which includes the posterior calcaneal facet and other three volumes of the anterior region. Calculated for the radius were total volume, volume of the radius head, volume of the diaphysis, and volume of the distal end. The data are presented for all of the variables, distinguishing between the right and left side. The data were processed using the statistical program PASW Statistics 18, thereby obtaining classification functions for sex which accurately classify 90.9 % of tali and 93.9 % of radii on the basis of their total left and right volume, respectively. Studying the volume in different regions of the bone shows that the diaphysis of the right radius possesses a high level of discriminant power, offering classification functions which accurately classify 96.9 % of the sample. The validation test performed on a sample of 20 individuals from another contemporary Spanish reference collection (EML 2) confirms the high discriminant power of the volume obtaining an accurate classification rate of 80-95 % depending on the variable studied. PMID:22592209

  12. Increase of bone volume by a nanosecond pulsed laser irradiation is caused by a decreased osteoclast number and an activated osteoblasts.

    PubMed

    Ninomiya, Tadashi; Hosoya, Akihiro; Nakamura, Hiroaki; Sano, Kazuo; Nishisaka, Tsuyoshi; Ozawa, Hidehiro

    2007-01-01

    The biostimulatory effects of laser irradiation focus not only in the field of soft tissue but also bone formation. Studies have shown that the light of a nanosecond pulsed laser which has a high peak power can produce stress waves in tissue. We have hypothesized that nanosecond pulsed laser irradiation stimulates bone formation. Our aim was to clarify the mechanism of increased bone volume by nanosecond pulsed laser irradiation. Rat femur was irradiated with a Q-switched Nd:YAG laser, which has a wavelength of 1064 nm. The quantification of trabecular architecture using three-dimensional morphometric analysis and measurement of bone mineral density (BMD) using pQCT was performed on day 1, day 3, day 5, and day 7 after laser irradiation. The laser effects on bone cells were also investigated using histological and immunohistochemical analysis. On day 1 after laser irradiation, bone volume (BV/TV), trabecular thickness (Tb.Th), and other parameters of the irradiated group did not significantly differ from the non-irradiation group (control). However, the mean BV/TV, Tb.Th, mineral apposition rate, and BMD of the laser group on day 7 after laser irradiation were significantly greater than those of the control. On histological analysis, the number of TRAP-positive osteoclasts was lower on day 3 after laser irradiation. Osteoblasts with activated clearance were seen in the laser irradiated group on day 1 and day 3. These data reveal that the increased bone volume by nanosecond pulsed laser irradiation causes an increase in osteoblast activity and a decrease in osteoclast number. PMID:16978938

  13. 21 CFR 1404.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Adequate evidence. 1404.900 Section 1404.900 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.900 Adequate evidence. Adequate evidence means information sufficient to support the reasonable belief that a particular...

  14. 29 CFR 98.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Adequate evidence. 98.900 Section 98.900 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 98.900 Adequate evidence. Adequate evidence means information sufficient to support the reasonable belief that a...

  15. Nonscientific Factors Associated with Acceptance for Publication in The Journal of Bone and Joint Surgery (American Volume)

    PubMed Central

    Okike, Kanu; Kocher, Mininder S.; Mehlman, Charles T.; Heckman, James D.; Bhandari, Mohit

    2008-01-01

    Background: While it is widely accepted that scientific factors may render a study more likely to be accepted for publication, it is less clear whether nonscientific factors may also be associated with publication. The purpose of this study was to identify the nonscientific factors associated with acceptance for publication by The Journal of Bone and Joint Surgery (American Volume). Methods: A total of 1173 manuscripts submitted to The Journal of Bone and Joint Surgery between January 1, 2004, and June 30, 2005, for publication as scientific articles were analyzed as part of a study on publication bias in the editorial decision-making process. Information was collected on nonscientific factors plausibly associated with acceptance for publication, including study location, conflict-of-interest disclosure, sex of the author, primary language, and the number of prior publications by the corresponding author in frequently cited orthopaedic journals. The final disposition term (acceptance or rejection) was recorded, and logistic regression was used to identify factors associated with acceptance for publication. Results: Manuscripts from countries other than the United States or Canada were significantly less likely to be accepted (odds ratio, 0.51; 95% confidence interval, 0.28 to 0.92; p = 0.026). Factors positively associated with acceptance for publication were conflict-of-interest disclosure involving a nonprofit entity (odds ratio, 1.92; 95% confidence interval, 1.35 to 2.73; p < 0.001) and ten or more prior publications in frequently cited orthopaedic journals by the corresponding author (odds ratio, 2.01; 95% confidence interval, 1.33 to 3.05; p = 0.001). We did not find a significant association between acceptance and conflict-of-interest disclosure involving a for-profit company, sex of the corresponding author, or primary language. Conclusions: Manuscripts submitted to The Journal of Bone and Joint Surgery were more likely to be accepted if they were from the

  16. Microcomputed tomographic analysis of human condyles in unilateral condylar hyperplasia: increased cortical porosity and trabecular bone volume fraction with reduced mineralisation.

    PubMed

    Karssemakers, L H E; Nolte, J W; Tuinzing, D B; Langenbach, G E J; Raijmakers, P G; Becking, A G

    2014-12-01

    Unilateral condylar hyperplasia or hyperactivity is a disorder of growth that affects the mandible, and our aim was to visualise the 3-dimensional bony microstructure of resected mandibular condyles of affected patients. We prospectively studied 17 patients with a clinical presentation of progressive mandibular asymmetry and an abnormal single-photon emission computed tomographic (SPECT) scan. All patients were treated by condylectomy to arrest progression. The resected condyles were scanned with micro-CT (18 μm resolution). Rectangular volumes of interest were selected in 4 quadrants (lateromedial and superoinferior) of the trabecular bone of each condyle. Variables of bone architecture (volume fraction, trabecular number, thickness, and separation, degree of mineralisation, and degree of structural anisotrophy) were calculated with routine morphometric software. Eight of the 17 resected condyles showed clear destruction of the subchondral layer of cortical bone. There was a significant superoinferior gradient for all trabecular variables. Mean (SD) bone volume fraction (25.1 (6) %), trabecular number (1.69 (0.26) mm(-1)), trabecular thickness (0.17 (0.03) mm), and degree of mineralisation (695.39 (39.83) mg HA/cm(3)) were higher in the superior region. Trabecular separation (0.6 (0.16) mm) and structural anisotropy (1.84 (0.28)) were higher in the inferior region. The micro-CT analysis showed increased cortical porosity in many of the condyles studied. It also showed a higher bone volume fraction, greater trabecular thickness and trabecular separation, greater trabecular number, and less mineralisation in the condyles of the 17 patients compared with the known architecture of unaffected mandibular condyles. PMID:25219775

  17. Biomechanical Comparison of Pedicle Screw Augmented with Different Volumes of Polymethylmethacrylate in Osteoporotic and Severely Osteoporotic Synthetic Bone Blocks in Primary Implantation: An Experimental Study

    PubMed Central

    Liu, Da; Zhang, Xiao-jun; Liao, Dong-fa; Zhou, Jiang-jun; Li, Zhi-qiang; Zhang, Bo; Wang, Cai-ru; Lei, Wei; Kang, Xia; Zheng, Wei

    2016-01-01

    This study was designed to compare screw stabilities augmented with different volumes of PMMA and analyze relationship between screw stability and volume of PMMA and optimum volume of PMMA in different bone condition. Osteoporotic and severely osteoporotic synthetic bone blocks were divided into groups A0-A5 and B0-B5, respectively. Different volumes of PMMA were injected in groups A0 to A5 and B0 to B5. Axial pullout tests were performed and Fmax was measured. Fmax in groups A1-A5 were all significantly higher than group A0. Except between groups A1 and A2, A3 and A4, and A4 and A5, there were significant differences on Fmax between any other two groups. Fmax in groups B1-B5 were all significantly higher than group B0. Except between groups B1 and B2, B2 and B3, and B4 and B5, there were significant differences on Fmax between any other two groups. There was significantly positive correlation between Fmax and volume of PMMA in osteoporotic and severely osteoporotic blocks. PMMA can significantly enhance pedicle screw stability in osteoporosis and severe osteoporosis. There were positive correlations between screw stability and volume of PMMA. In this study, injection of 3 mL and 4 mL PMMA was preferred in osteoporotic and severely osteoporotic blocks, respectively. PMID:26885525

  18. Vitamin D receptor overexpression in osteoblasts and osteocytes prevents bone loss during vitamin D-deficiency.

    PubMed

    Lam, Nga N; Triliana, Rahma; Sawyer, Rebecca K; Atkins, Gerald J; Morris, Howard A; O'Loughlin, Peter D; Anderson, Paul H

    2014-10-01

    There are several lines of evidence that demonstrate the ability of 1,25-dihydroxyvitamin D (1,25(OH)2D3), acting via the vitamin D receptor (VDR) to mediate negative or positive effects in bone. Transgenic over-expression of VDR in osteoblasts and osteocytes in a mouse model (OSVDR) has been previously shown to inhibit processes of bone resorption and enhance bone formation, under conditions of adequate calcium intake. While these findings suggest that vitamin D signalling in osteoblasts and osteocytes promotes bone mineral accrual, the vitamin D requirement for this action is not well understood. In this study, 4 week old female OSVDR and wild-type (WT) mice were fed either a vitamin D-replete (1000IU/kg diet, D+) or vitamin D-deficient (D-) diet for 4 months to observe changes to bone mineral homeostasis. Tibial bone mineral volume was analysed by micro-CT and changes to bone cell activities were measured using standard dynamic histomorphometric techniques. While vitamin D-deplete WT mice demonstrated a reduction in periosteal bone accrual and overall bone mineral volume, OSVDR mice, however, displayed increased cortical and cancellous bone volume in mice which remained higher during vitamin D-depletion due to a reduced osteoclast number and increased bone formation rate. These data suggest that increased VDR-mediated activity in osteoblast and osteocytes prevents bone loss due to vitamin D-deficiency. This article is part of a Special Issue entitled '16th Vitamin D Workshop'. PMID:24434283

  19. Cortical tibial bone volume in two strains of mice: effects of sciatic neurectomy and genetic regulation of bone response to mechanical loading.

    PubMed

    Kodama, Y; Dimai, H P; Wergedal, J; Sheng, M; Malpe, R; Kutilek, S; Beamer, W; Donahue, L R; Rosen, C; Baylink, D J; Farley, J

    1999-08-01

    Although C3H/HeJ (C3H) and C57BL/6J (B6) mice are similar in body size (and adult weight), and have bones of similar external size, C3H mice have higher peak bone densities than B6 mice (e.g., 53% higher peak bone density in the femora). The current studies were intended to assess the role of mechanical loading/unloading as a possible determinant of the bone density difference between these inbred strains of mice and, specifically, to assess the effect of sciatic neurectomy on histomorphometric indices of bone formation and resorption in the tibiae of female C3H and B6 mice. Groups of 10 mice of each strain were subjected to left-side sciatic neurectomy (left hindlimb immobilization) or a sham procedure. The contralateral (right) legs of each mouse were used as controls. Four weeks of immobilization produced no systemic changes in bone formation indices in either strain of mice (i.e., no change in serum alkaline phosphatase or serum osteocalcin). However, histomorphometric assessments at the tibiofibular junction showed that 4 weeks of immobilization caused a time-dependent decrease in the length of the endosteal bone forming perimeter (e.g., 14% of control single-labeled, noneroded surface at 4 weeks, p < 0.005) with a concomitant increase in the length of the endosteal bone resorbing perimeter (i.e., 424% of control eroded surface at 4 weeks, p < 0.005), in the B6 mice. These effects were associated with an increase in medullary area (132% of control, p < 0.05) at this site, in the B6 mice. The pattern of response was different in the tibiae of the C3 mice-a much smaller decrease in bone forming perimeter (88% of control at 4 weeks, p < 0.05), with no associated increase in bone resorbing perimeter, and no change in medullary area. Similar effects were seen at a second cross-sectional sampling site, in the proximal tibia. Together, these findings indicate that B6 mice are more sensitive to endosteal bone loss from hindlimb immobilization than C3H mice. PMID

  20. 34 CFR 85.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Definitions § 85.900 Adequate evidence. Adequate evidence means information sufficient to support the reasonable belief that a particular act or omission has occurred. Authority: E.O. 12549 (3 CFR, 1986 Comp., p. 189); E.O 12689 (3 CFR, 1989 Comp., p. 235); 20 U.S.C. 1082, 1094, 1221e-3 and 3474; and Sec....

  1. 29 CFR 452.110 - Adequate safeguards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 2 2010-07-01 2010-07-01 false Adequate safeguards. 452.110 Section 452.110 Labor... DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members § 452.110 Adequate safeguards. (a) In addition to the election safeguards discussed in this part, the Act contains a general mandate in section...

  2. 29 CFR 452.110 - Adequate safeguards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 2 2011-07-01 2011-07-01 false Adequate safeguards. 452.110 Section 452.110 Labor... DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members § 452.110 Adequate safeguards. (a) In addition to the election safeguards discussed in this part, the Act contains a general mandate in section...

  3. [Bone quality and strength relating with bone remodeling].

    PubMed

    Mori, Satoshi

    2016-01-01

    The bone has the functions of mineral reservoir and mechanical support as skeleton. Bone remodeling is the adult mode of bone metabolism, replacing old bone tissue to new one. Bone strength is determined by bone volume, structure and quality such as micro damage, degree of mineralization and collagen cross linkage, which are all controlled by bone remodeling. Bone strength decreases under high turn-over condition by decreasing bone volume and deterioration of bone structure, which also decreases under low turn-over condition by increased micro damage, increasing mineralization and AGE collagen cross linkage. PMID:26728527

  4. Americans Getting Adequate Water Daily, CDC Finds

    MedlinePlus

    ... medlineplus/news/fullstory_158510.html Americans Getting Adequate Water Daily, CDC Finds Men take in an average ... new government report finds most are getting enough water each day. The data, from the U.S. National ...

  5. Americans Getting Adequate Water Daily, CDC Finds

    MedlinePlus

    ... gov/news/fullstory_158510.html Americans Getting Adequate Water Daily, CDC Finds Men take in an average ... new government report finds most are getting enough water each day. The data, from the U.S. National ...

  6. Serial Scanning and Registration of High Resolution Quantitative Computed Tomography Volume Scans for the Determination of Local Bone Density Changes

    NASA Technical Reports Server (NTRS)

    Whalen, Robert T.; Napel, Sandy; Yan, Chye H.

    1996-01-01

    Progress in development of the methods required to study bone remodeling as a function of time is reported. The following topics are presented: 'A New Methodology for Registration Accuracy Evaluation', 'Registration of Serial Skeletal Images for Accurately Measuring Changes in Bone Density', and 'Precise and Accurate Gold Standard for Multimodality and Serial Registration Method Evaluations.'

  7. Volume shrinkage of bone, brain and muscle tissue in sample preparation for micro-CT and light sheet fluorescence microscopy (LSFM).

    PubMed

    Buytaert, Jan; Goyens, Jana; De Greef, Daniel; Aerts, Peter; Dirckx, Joris

    2014-08-01

    Two methods are especially suited for tomographic imaging with histological detail of macroscopic samples that consist of multiple tissue types (bone, muscle, nerve or fat): Light sheet (based) fluorescence microscopy (LSFM) and micro-computed tomography (micro-CT). Micro-CT requires staining with heavy chemical elements (and thus fixation and sometimes dehydration) in order to make soft tissue imageable when measured alongside denser structures. LSMF requires fixation, decalcification, dehydration, clearing and staining with a fluorescent dye. The specimen preparation of both imaging methods is prone to shrinkage, which is often not mentioned, let alone quantified. In this paper the presence and degree of shrinkage are quantitatively identified for the selected preparation methods/stains. LSFM delivers a volume shrinkage of 17% for bone, 56% for muscle and 62% for brain tissue. The three most popular micro-CT stains (phosphotungstic acid, iodine with potassium iodide, and iodine in absolute ethanol) deliver a volume shrinkage ranging from 10 to 56% for muscle and 27-66% for brain, while bone does not shrink in micro-CT preparation. PMID:24963987

  8. Asbestos/NESHAP adequately wet guidance

    SciTech Connect

    Shafer, R.; Throwe, S.; Salgado, O.; Garlow, C.; Hoerath, E.

    1990-12-01

    The Asbestos NESHAP requires facility owners and/or operators involved in demolition and renovation activities to control emissions of particulate asbestos to the outside air because no safe concentration of airborne asbestos has ever been established. The primary method used to control asbestos emissions is to adequately wet the Asbestos Containing Material (ACM) with a wetting agent prior to, during and after demolition/renovation activities. The purpose of the document is to provide guidance to asbestos inspectors and the regulated community on how to determine if friable ACM is adequately wet as required by the Asbestos NESHAP.

  9. Evaluation of bone marrow lesion volume as a knee osteoarthritis biomarker - longitudinal relationships with pain and structural changes: data from the Osteoarthritis Initiative

    PubMed Central

    2013-01-01

    Introduction Bone marrow lesion (BML) size may be an important imaging biomarker for osteoarthritis-related clinical trials and reducing BML size may be an important therapeutic goal. However, data on the interrelationships between BML size, pain, and structural progression are inconsistent and rarely examined in the same cohort. Therefore, we evaluated the cross-sectional and longitudinal associations of BML volume with knee pain and joint space narrowing (JSN). Methods A BML volume assessment was performed on magnetic resonance images of the knee collected at the 24- and 48-month Osteoarthritis Initiative visits from a convenience sample of 404 participants in the progression cohort. During the same visits, knee pain was assessed with WOMAC pain scores and knee radiographs were acquired and scored for JSN. BML volume was summed to generate a total knee volume and an index tibiofemoral compartment volume (compartment with greater baseline JSN). Primary analyses included multiple linear regressions (outcome = pain, predictor = total knee BML volume) and logistic regressions (outcome = JSN, predictor = index tibiofemoral compartment BML volume). Results This sample was 49% female with a mean age of 63 (9.2 standard deviation (SD)) years, and 71% had radiographic osteoarthritis in the study knee. Larger baseline BMLs were associated with greater baseline knee pain (P = 0.01), the presence of JSN at baseline (odds ratio (OR) = 1.50, 95% confidence interval (CI) = 1.23 to 1.83), and JSN progression (OR = 1.27, 95%CI = 1.11 to 1.46). Changes in total knee BML volume had a positive association with changes in knee pain severity (P = 0.004) and this association may be driven by knees that were progressing from no or small baseline BMLs to larger BMLs. In contrast, we found no linear positive relationship between BML volume change and JSN progression. Instead, regression of medial tibiofemoral BML volume was associated with JSN progression compared to knees with no or

  10. Adequate supervision for children and adolescents.

    PubMed

    Anderst, James; Moffatt, Mary

    2014-11-01

    Primary care providers (PCPs) have the opportunity to improve child health and well-being by addressing supervision issues before an injury or exposure has occurred and/or after an injury or exposure has occurred. Appropriate anticipatory guidance on supervision at well-child visits can improve supervision of children, and may prevent future harm. Adequate supervision varies based on the child's development and maturity, and the risks in the child's environment. Consideration should be given to issues as wide ranging as swimming pools, falls, dating violence, and social media. By considering the likelihood of harm and the severity of the potential harm, caregivers may provide adequate supervision by minimizing risks to the child while still allowing the child to take "small" risks as needed for healthy development. Caregivers should initially focus on direct (visual, auditory, and proximity) supervision of the young child. Gradually, supervision needs to be adjusted as the child develops, emphasizing a safe environment and safe social interactions, with graduated independence. PCPs may foster adequate supervision by providing concrete guidance to caregivers. In addition to preventing injury, supervision includes fostering a safe, stable, and nurturing relationship with every child. PCPs should be familiar with age/developmentally based supervision risks, adequate supervision based on those risks, characteristics of neglectful supervision based on age/development, and ways to encourage appropriate supervision throughout childhood. PMID:25369578

  11. Small Rural Schools CAN Have Adequate Curriculums.

    ERIC Educational Resources Information Center

    Loustaunau, Martha

    The small rural school's foremost and largest problem is providing an adequate curriculum for students in a changing world. Often the small district cannot or is not willing to pay the per-pupil cost of curriculum specialists, specialized courses using expensive equipment no more than one period a day, and remodeled rooms to accommodate new…

  12. Funding the Formula Adequately in Oklahoma

    ERIC Educational Resources Information Center

    Hancock, Kenneth

    2015-01-01

    This report is a longevity, simulational study that looks at how the ratio of state support to local support effects the number of school districts that breaks the common school's funding formula which in turns effects the equity of distribution to the common schools. After nearly two decades of adequately supporting the funding formula, Oklahoma…

  13. Assessment of treatment response by total tumor volume and global apparent diffusion coefficient using diffusion-weighted MRI in patients with metastatic bone disease: a feasibility study.

    PubMed

    Blackledge, Matthew D; Collins, David J; Tunariu, Nina; Orton, Matthew R; Padhani, Anwar R; Leach, Martin O; Koh, Dow-Mu

    2014-01-01

    We describe our semi-automatic segmentation of whole-body diffusion-weighted MRI (WBDWI) using a Markov random field (MRF) model to derive tumor total diffusion volume (tDV) and associated global apparent diffusion coefficient (gADC); and demonstrate the feasibility of using these indices for assessing tumor burden and response to treatment in patients with bone metastases. WBDWI was performed on eleven patients diagnosed with bone metastases from breast and prostate cancers before and after anti-cancer therapies. Semi-automatic segmentation incorporating a MRF model was performed in all patients below the C4 vertebra by an experienced radiologist with over eight years of clinical experience in body DWI. Changes in tDV and gADC distributions were compared with overall response determined by all imaging, tumor markers and clinical findings at serial follow up. The segmentation technique was possible in all patients although erroneous volumes of interest were generated in one patient because of poor fat suppression in the pelvis, requiring manual correction. Responding patients showed a larger increase in gADC (median change = +0.18, range = -0.07 to +0.78 × 10(-3) mm2/s) after treatment compared to non-responding patients (median change = -0.02, range = -0.10 to +0.05 × 10(-3) mm2/s, p = 0.05, Mann-Whitney test), whereas non-responding patients showed a significantly larger increase in tDV (median change = +26%, range = +3 to +284%) compared to responding patients (median change = -50%, range = -85 to +27%, p = 0.02, Mann-Whitney test). Semi-automatic segmentation of WBDWI is feasible for metastatic bone disease in this pilot cohort of 11 patients, and could be used to quantify tumor total diffusion volume and median global ADC for assessing response to treatment. PMID:24710083

  14. Aesthetic recovery of alveolar atrophy following autogenous onlay bone grafting using interconnected porous hydroxyapatite ceramics (IP-CHA) and resorbable poly-L-lactic/polyglycolic acid screws: case report

    PubMed Central

    2014-01-01

    Background Onlay bone grafting techniques have some problems related to the limited volume of autogenous grafted bone and need for surgery to remove bone fixing screws. Here, we report a case of horizontal alveolar ridge atrophy following resection of a maxillary bone cyst, in which autogenous onlay bone grafting with interconnected porous hydroxyapatite ceramics (IP-CHA) and bioresorbable poly-L-lactic/polyglycolic acid (PLLA-PGA) screws was utilized. Case presentation A 51-year-old man had aesthetic complications related to alveolar atrophy following maxillary bone cyst extraction. We performed onlay grafting for aesthetic alveolar bone recovery using IP-CHA to provide adequate horizontal bone volume and PLLA-PGA screws for bone fixing to avoid later damage to host bone during surgical removal. During the operation, an autogenous cortical bone block was collected from the ramus mandibular and fixed to the alveolar ridge with PLLA-PGA screws, then the gap between the bone block and recipient bone was filled with a granular type of IP-CHA. Post-surgery orthopantomograph and CT scan findings showed no abnormal resorption of the grafted bone, and increased radiopacity, which indicated new bone formation in the area implanted with IP-CHA. Conclusion Our results show that IP-CHA and resorbable PLLA-PGA screws are useful materials for autogenous onlay bone grafting. PMID:24889647

  15. Unbiased Stereological Estimation of the Spiral Ligament and Stria Vascularis Volumes in Aging and Ménière’s Disease Using Archival Human Temporal Bones

    PubMed Central

    Ishiyama, Gail; Tokita, Joshua; Lopez, Ivan; Tang, Yong

    2006-01-01

    The present study applies the unbiased stereological technique—Cavalieri principle to measure the volumes of the stria vascularis (SV) and the spiral ligament (SL) using postmortem archival human temporal bones from normal young and older subjects and subjects with Ménière’s disease. Normative data was obtained from subjects without ages ranging from 15 to 84 years old who had no history of audiovestibular disease (N = 25). For comparison purposes, the normative specimens were divided into three groups: group 1 (n = 8) had ages ranging from 15 to 38 years old, average age = 23.9; group 2 (n = 8) had ages ranging from 51 to 59 years old, average age = 55.1; group 3 (n = 9) had ages ranging from 64 to 84 years old, average age = 74.3. The average SV volume of group 3 (0.479 mm3) was significantly lower than that of group 1 (0.705 mm3) (p < 0.0005) and was significantly lower than that of group 2 (0.603 mm3) (p = 0.01). The average SL volume of group 3 (8.42 mm3) was significantly lower than that of group 1 (9.54 mm3) (p<0.05), but was not significantly lower than that of group 2 (8.58 mm3). Five subjects with Ménière’s disease, confirmed by histopathological examination (ages ranging from 63 to 91 years old, average age = 73.4), were studied. The average SV volume in Ménière’s subjects (0.378 mm3) was significantly lower than age-matched controls (p<0.05). The average SL volume in Ménière’s subjects (7.01 mm3) was also significantly lower than age-matched controls (p<0.05). The SV and SL volumes were unaffected by gender. The present study demonstrates for the first time the use of the unbiased stereological technique—Cavalieri principle—as a reliable and efficient method to obtain volumetric estimates of the SV and the SL by using archival human temporal bone specimens. PMID:17160359

  16. Volume of Bone Metastasis Assessed with Whole-Body Diffusion-weighted Imaging Is Associated with Overall Survival in Metastatic Castration-resistant Prostate Cancer.

    PubMed

    Perez-Lopez, Raquel; Lorente, David; Blackledge, Matthew D; Collins, David J; Mateo, Joaquin; Bianchini, Diletta; Omlin, Aurelius; Zivi, Andrea; Leach, Martin O; de Bono, Johann S; Koh, Dow-Mu; Tunariu, Nina

    2016-07-01

    Purpose To determine the correlation between the volume of bone metastasis as assessed with diffusion-weighted (DW) imaging and established prognostic factors in metastatic castration-resistant prostate cancer (mCRPC) and the association with overall survival (OS). Materials and Methods This retrospective study was approved by the institutional review board; informed consent was obtained from all patients. The authors analyzed whole-body DW images obtained between June 2010 and February 2013 in 53 patients with mCRPC at the time of starting a new line of anticancer therapy. Bone metastases were identified and delineated on whole-body DW images in 43 eligible patients. Total tumor diffusion volume (tDV) was correlated with the bone scan index (BSI) and other prognostic factors by using the Pearson correlation coefficient (r). Survival analysis was performed with Kaplan-Meier analysis and Cox regression. Results The median tDV was 503.1 mL (range, 5.6-2242 mL), and the median OS was 12.9 months (95% confidence interval [CI]: 8.7, 16.1 months). There was a significant correlation between tDV and established prognostic factors, including hemoglobin level (r = -0.521, P < .001), prostate-specific antigen level (r = 0.556, P < .001), lactate dehydrogenase level (r = 0.534, P < .001), alkaline phosphatase level (r = 0.572, P < .001), circulating tumor cell count (r = 0.613, P = .004), and BSI (r = 0.565, P = .001). A higher tDV also showed a significant association with poorer OS (hazard ratio, 1.74; 95% CI: 1.02, 2.96; P = .035). Conclusion Metastatic bone disease from mCRPC can be evaluated and quantified with whole-body DW imaging. Whole-body DW imaging-generated tDV showed correlation with established prognostic biomarkers and is associated with OS in mCRPC. (©) RSNA, 2016 Online supplemental material is available for this article. PMID:26807894

  17. The reaction of cortical bone to compression by screw threads.

    PubMed

    Schatzker, J; Horne, J G; Sumner-Smith, G

    1975-09-01

    Cortical bone subjected to compression by screw threads retains its integrity and is not resorbed. Screws which generate compression at the interface of their threads with bone can be expected to provide adequate fixation until bone union occurs. PMID:1157421

  18. Adequate peritoneal dialysis: theoretical model and patient treatment.

    PubMed

    Tast, C

    1998-01-01

    The objective of this study was to evaluate the relationship between adequate PD with sufficient weekly Kt/V (2.0) and Creatinine clearance (CCR) (60l) and necessary daily dialysate volume. This recommended parameter was the result of a recent multi-centre study (CANUSA). For this there were 40 patients in our hospital examined and compared in 1996, who carried out PD for at least 8 weeks and up to 6 years. These goals (CANUSA) are easily attainable in the early treatment of many individuals with a low body surface area (BSA). With higher BSA or missing RRF (Residual Renal Function) the daily dose of dialysis must be adjusted. We found it difficult to obtain the recommended parameters and tried to find a solution to this problem. The simplest method is to increase the volume or exchange rate. The most expensive method is to change from CAPD to APD with the possibility of higher volume or exchange rates. Selection of therapy must take into consideration: 1. patient preference, 2. body mass, 3. peritoneal transport rates, 4. ability to perform therapy, 5. cost of therapy and 6. risk of peritonitis. With this information in mind, an individual prescription can be formulated and matched to the appropriate modality of PD. PMID:10392062

  19. [Microdestruction of the bone].

    PubMed

    Iankovskiĭ, V É

    2014-01-01

    The objective of the present study was the detection of microcracks in the compact bone tissue surrounding the fracture and in deformed bone undergoing subcritical loading. The portions of deformed bone tissue and terminal fragments of broken bones were obtained in the form of blocks longitudinally sawcut from the regions of primary and secondary bone rupture. A total of 300 such blocks were available for the examination. All portions of the deformed bone tissue and terminal fragments of broken bones showed up microcracks commensurate with the bone structures. They were actually hardened traces of deformation that preceded the fracture and reflected the volume of the destroyed bone tissue; moreover, in certain cases they allowed to identify the kind of the object that exerted the external action (either a blow or slow bending). PMID:25269164

  20. Is a vegetarian diet adequate for children.

    PubMed

    Hackett, A; Nathan, I; Burgess, L

    1998-01-01

    The number of people who avoid eating meat is growing, especially among young people. Benefits to health from a vegetarian diet have been reported in adults but it is not clear to what extent these benefits are due to diet or to other aspects of lifestyles. In children concern has been expressed concerning the adequacy of vegetarian diets especially with regard to growth. The risks/benefits seem to be related to the degree of restriction of he diet; anaemia is probably both the main and the most serious risk but this also applies to omnivores. Vegan diets are more likely to be associated with malnutrition, especially if the diets are the result of authoritarian dogma. Overall, lacto-ovo-vegetarian children consume diets closer to recommendations than omnivores and their pre-pubertal growth is at least as good. The simplest strategy when becoming vegetarian may involve reliance on vegetarian convenience foods which are not necessarily superior in nutritional composition. The vegetarian sector of the food industry could do more to produce foods closer to recommendations. Vegetarian diets can be, but are not necessarily, adequate for children, providing vigilance is maintained, particularly to ensure variety. Identical comments apply to omnivorous diets. Three threats to the diet of children are too much reliance on convenience foods, lack of variety and lack of exercise. PMID:9670174

  1. Probiotic use decreases intestinal inflammation and increases bone density in healthy male but not female mice.

    PubMed

    McCabe, Laura R; Irwin, Regina; Schaefer, Laura; Britton, Robert A

    2013-08-01

    Osteoporosis can result from intestinal inflammation, as is seen with inflammatory bowel disease. Probiotics, microorganisms that provide a health benefit to the host when ingested in adequate amounts, can have anti-inflammatory properties and are currently being examined to treat inflammatory bowel disease. Here, we examined if treating healthy male mice with Lactobacillus reuteri ATCC PTA 6475 (a candidate probiotic with anti-TNFα activity) could affect intestinal TNFα levels and enhance bone density. Adult male mice were given L. reuteri 6475 orally by gavage for 3×/week for 4 weeks. Examination of jejunal and ileal RNA profiles indicates that L. reuteri suppressed basal TNFα mRNA levels in the jejunum and ileum in male mice, but surprisingly not in female mice. Next, we examined bone responses. Micro-computed tomography demonstrated that L. reuteri 6475 treatment increased male trabecular bone parameters (mineral density, bone volume fraction, trabecular number, and trabecular thickness) in the distal femur metaphyseal region as well as in the lumbar vertebrae. Cortical bone parameters were unaffected. Dynamic and static histomorphometry and serum remodeling parameters indicate that L. reuteri ingestion increases osteoblast serum markers and dynamic measures of bone formation in male mice. In contrast to male mice, L. reuteri had no effect on bone parameters in female mice. Taken together our studies indicate that femoral and vertebral bone formation increases in response to oral probiotic use, leading to increased trabecular bone volume in male mice. PMID:23389860

  2. Bone Grafts

    MedlinePlus

    A bone graft transplants bone tissue. Surgeons use bone grafts to repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some ...

  3. Bone tumor

    MedlinePlus

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  4. [Bone and Nutrition. Bone and phosphorus intake].

    PubMed

    Arai, Hidekazu; Sakuma, Masae

    2015-07-01

    Phosphorus is necessary for bone mineralization. Although adequate phosphorus intake is essential for skeletal mineralization, it is reported that excessive phosphorus intake can induce deleterious effect on bone. Recently, since the Japanese diet has been westernized, phosphorus intake by the meat and dairy products has increased. Furthermore, along with the development of processed foods, excessive intake of inorganic phosphorus from food additives has become a problem. An adverse effect on parathyroid hormone (PTH) secretion from high phosphorus intake was seen only when calcium intake was inadequate. Dietary calcium to phosphorus ratio can be considered as one of the indicators that can predict the health of the bone. PMID:26119308

  5. Early tissue responses to zoledronate, locally delivered by bone screw, into a compromised cancellous bone site: a pilot study

    PubMed Central

    2014-01-01

    Background In fracture treatment, adequate fixation of implants is crucial to long-term clinical performance. Bisphosphonates (BP), potent inhibitors of osteoclastic bone resorption, are known to increase peri-implant bone mass and accelerate primary fixation. However, adverse effects are associated with systemic use of BPs. Thus, Zoledronic acid (ZOL) a potent BP was loaded on bone screws and evaluated in a local delivery model. Whilst mid- to long-term effects are already reported, early cellular events occurring at the implant/bone interface are not well described. The present study investigated early tissue responses to ZOL locally delivered, by bone screw, into a compromised cancellous bone site. Methods ZOL was immobilized on fibrinogen coated titanium screws. Using a bilateral approach, ZOL loaded test and non-loaded control screws were implanted into femoral condyle bone defects, created by an overdrilling technique. Histological analyses of the local tissue effects such as new bone formation and osteointegration were performed at days 1, 5 and 10. Results Histological evaluation of the five day ZOL group, demonstrated a higher osseous differentiation trend. At ten days an early influx of mesenchymal and osteoprogenitor cells was seen and a higher level of cellular proliferation and differentiation (p < 5%). In the ZOL group bone-to-screw contact and bone volume values within the defect tended to increase. Local drug release did not induce any adverse cellular effects. Conclusion This study indicates that local ZOL delivery into a compromised cancellous bone site actively supports peri-implant osteogenesis, positively affecting mesenchymal cells, at earlier time points than previously reported in the literature. PMID:24656151

  6. Trabecular bone of precocials at birth; Are they prepared to run for the wolf(f)?

    PubMed

    Gorissen, Ben M C; Wolschrijn, Claudia F; van Vilsteren, Anouk A M; van Rietbergen, Bert; van Weeren, P René

    2016-07-01

    Bone is a dynamic tissue adapting to loading according to "Wolff's law of bone adaptation." During very early life, however, such a mechanism may not be adequate enough to adapt to the dramatic change in environmental challenges in precocial species. Their neonates are required to stand and walk within hours after birth, in contrast to altricial animals that have much more time to adapt from the intrauterine environment to the outside world. In this study, trabecular bone parameters of the talus and sagittal ridge of the tibia from stillborn but full-term precocials (calves and foals) were analyzed by micro-CT imaging in order to identify possible anticipatory mechanisms to loading. Calculated average bone volume fraction in the Shetland pony (49-74%) was significantly higher compared to Warmblood foals (28-51%). Bovine trabecular bone was characterized by a low average bone volume fraction (22-28%), however, more directional anisotropy was found. It is concluded that anticipatory strategies in skeletal development exist in precocial species, which differ per species and are most likely related to anatomical differences in joint geometry and related loading patterns. The underlying regulatory mechanisms are still unknown, but they may be based on a genetic blueprint for the development of bone. More knowledge, both about a possible blueprint and its regulation, will be helpful in understanding developmental bone and joint diseases. J. Morphol. 277:948-956, 2016. © 2016 Wiley Periodicals, Inc. PMID:27098190

  7. Bone Diseases

    MedlinePlus

    ... avoid smoking and drinking too much alcohol. Bone diseases can make bones easy to break. Different kinds ... break Osteogenesis imperfecta makes your bones brittle Paget's disease of bone makes them weak Bones can also ...

  8. 21 CFR 201.5 - Drugs; adequate directions for use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Drugs; adequate directions for use. 201.5 Section...) DRUGS: GENERAL LABELING General Labeling Provisions § 201.5 Drugs; adequate directions for use. Adequate directions for use means directions under which the layman can use a drug safely and for the purposes...

  9. 21 CFR 201.5 - Drugs; adequate directions for use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Drugs; adequate directions for use. 201.5 Section...) DRUGS: GENERAL LABELING General Labeling Provisions § 201.5 Drugs; adequate directions for use. Adequate directions for use means directions under which the layman can use a drug safely and for the purposes...

  10. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 4 Accounts 1 2010-01-01 2010-01-01 false Responsibility for maintaining adequate safeguards. 200.14 Section 200.14 Accounts RECOVERY ACCOUNTABILITY AND TRANSPARENCY BOARD PRIVACY ACT OF 1974 § 200.14 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining adequate technical, physical, and...

  11. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Responsibility for maintaining adequate safeguards. 1304.114 Section 1304.114 Energy NUCLEAR WASTE TECHNICAL REVIEW BOARD PRIVACY ACT OF 1974 § 1304.114 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining adequate technical, physical, and security...

  12. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Responsibility for maintaining adequate safeguards. 1304.114 Section 1304.114 Energy NUCLEAR WASTE TECHNICAL REVIEW BOARD PRIVACY ACT OF 1974 § 1304.114 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining adequate technical, physical, and security...

  13. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 4 Accounts 1 2011-01-01 2011-01-01 false Responsibility for maintaining adequate safeguards. 200....14 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining adequate technical, physical, and security safeguards to prevent unauthorized disclosure...

  14. Accuracy of DXA scanning of the thoracic spine: cadaveric studies comparing BMC, areal BMD and geometric estimates of volumetric BMD against ash weight and CT measures of bone volume.

    PubMed

    Sran, Meena M; Khan, Karim M; Keiver, Kathy; Chew, Jason B; McKay, Heather A; Oxland, Thomas R

    2005-12-01

    Biomechanical studies of the thoracic spine often scan cadaveric segments by dual energy X-ray absorptiometry (DXA) to obtain measures of bone mass. Only one study has reported the accuracy of lateral scans of thoracic vertebral bodies. The accuracy of DXA scans of thoracic spine segments and of anterior-posterior (AP) thoracic scans has not been investigated. We have examined the accuracy of AP and lateral thoracic DXA scans by comparison with ash weight, the gold-standard for measuring bone mineral content (BMC). We have also compared three methods of estimating volumetric bone mineral density (vBMD) with a novel standard-ash weight (g)/bone volume (cm3) as measured by computed tomography (CT). Twelve T5-T8 spine segments were scanned with DXA (AP and lateral) and CT. The T6 vertebrae were excised, the posterior elements removed and then the vertebral bodies were ashed in a muffle furnace. We proposed a new method of estimating vBMD and compared it with two previously published methods. BMC values from lateral DXA scans displayed the strongest correlation with ash weight (r=0.99) and were on average 12.8% higher (p<0.001). As expected, BMC (AP or lateral) was more strongly correlated with ash weight than areal bone mineral density (aBMD; AP: r=0.54, or lateral: r=0.71) or estimated vBMD. Estimates of vBMD with either of the three methods were strongly and similarly correlated with volumetric BMD calculated by dividing ash weight by CT-derived volume. These data suggest that readily available DXA scanning is an appropriate surrogate measure for thoracic spine bone mineral and that the lateral scan might be the scan method of choice. PMID:15616862

  15. Bone and Celiac Disease.

    PubMed

    Zanchetta, María Belén; Longobardi, Vanesa; Bai, Julio César

    2016-04-01

    More than 50 % of untreated patients with celiac disease (CD) have bone loss detected by bone densitometry (dual-energy X-ray absorptiometry:DXA). Moreover, patients with CD are more likely to have osteoporosis and fragility fractures, especially of the distal radius. Although still controversial, we recommend DXA screening in all celiac disease patients, particularly in those with symptomatic CD at diagnosis and in those who present risk factors for fracture such as older age, menopausal status, previous fracture history, and familial hip fracture history. Bone microarchitecture, especially the trabecular network, may be deteriorated, explaining the higher fracture risk in these patients. Adequate calcium and vitamin D supplementation are also recommended to optimize bone recovery, especially during the first years of gluten free diet (GFD). If higher fracture risk persists after 1 or 2 years of GFD, specific osteoactive treatment may be necessary to improve bone health. PMID:26875096

  16. Space flight and bone formation

    NASA Technical Reports Server (NTRS)

    Doty, St B.

    2004-01-01

    Major physiological changes which occur during spaceflight include bone loss, muscle atrophy, cardiovascular and immune response alterations. When trying to determine the reason why bone loss occurs during spaceflight, one must remember that all these other changes in physiology and metabolism may also have impact on the skeletal system. For bone, however, the role of normal weight bearing is a major concern and we have found no adequate substitute for weight bearing which can prevent bone loss. During the study of this problem, we have learned a great deal about bone physiology and increased our knowledge about how normal bone is formed and maintained. Presently, we do not have adequate ground based models which can mimic the tissue loss that occurs in spaceflight but this condition closely resembles the bone loss seen with osteoporosis. Although a normal bone structure will respond to application of mechanical force and weight bearing by forming new bone, a weakened osteoporotic bone may have a tendency to fracture. The study of the skeletal system during weightless conditions will eventually produce preventative measures and form a basis for protecting the crew during long term space flight. The added benefit from these studies will be methods to treat bone loss conditions which occur here on earth.

  17. Bone Diseases

    MedlinePlus

    ... also avoid smoking and drinking too much alcohol. Bone diseases can make bones easy to break. Different kinds ... Bones can also develop cancer and infections Other bone diseases, which are caused by poor nutrition, genetics, or ...

  18. Bone Grafts

    MedlinePlus

    ... repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some types of fractures or cancers. Once your body accepts the bone ...

  19. Porous Surface Modified Bioactive Bone Cement for Enhanced Bone Bonding

    PubMed Central

    Huang, Li; Dong, Jingjing; Guo, Dagang; Mao, Mengmeng; Kong, Liang; Li, Yang; Wu, Zixiang; Lei, Wei

    2012-01-01

    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 defect. Conclusions

  20. Bone nutrients for vegetarians.

    PubMed

    Mangels, Ann Reed

    2014-07-01

    The process of bone mineralization and resorption is complex and is affected by numerous factors, including dietary constituents. Although some dietary factors involved in bone health, such as calcium and vitamin D, are typically associated with dairy products, plant-based sources of these nutrients also supply other key nutrients involved in bone maintenance. Some research suggests that vegetarian diets, especially vegan diets, are associated with lower bone mineral density (BMD), but this does not appear to be clinically significant. Vegan diets are not associated with an increased fracture risk if calcium intake is adequate. Dietary factors in plant-based diets that support the development and maintenance of bone mass include calcium, vitamin D, protein, potassium, and soy isoflavones. Other factors present in plant-based diets such as oxalic acid and phytic acid can potentially interfere with absorption and retention of calcium and thereby have a negative effect on BMD. Impaired vitamin B-12 status also negatively affects BMD. The role of protein in calcium balance is multifaceted. Overall, calcium and protein intakes in accord with Dietary Reference Intakes are recommended for vegetarians, including vegans. Fortified foods are often helpful in meeting recommendations for calcium and vitamin D. Plant-based diets can provide adequate amounts of key nutrients for bone health. PMID:24898231

  1. 7 CFR 4290.200 - Adequate capital for RBICs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Adequate capital for RBICs. 4290.200 Section 4290.200 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE SERVICE AND... Qualifications for the RBIC Program Capitalizing A Rbic § 4290.200 Adequate capital for RBICs. You must meet...

  2. 13 CFR 107.200 - Adequate capital for Licensees.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Adequate capital for Licensees... INVESTMENT COMPANIES Qualifying for an SBIC License Capitalizing An Sbic § 107.200 Adequate capital for... Licensee, and to receive Leverage. (a) You must have enough Regulatory Capital to provide...

  3. 13 CFR 107.200 - Adequate capital for Licensees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Adequate capital for Licensees... INVESTMENT COMPANIES Qualifying for an SBIC License Capitalizing An Sbic § 107.200 Adequate capital for... Licensee, and to receive Leverage. (a) You must have enough Regulatory Capital to provide...

  4. 7 CFR 4290.200 - Adequate capital for RBICs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Adequate capital for RBICs. 4290.200 Section 4290.200 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE SERVICE AND... Qualifications for the RBIC Program Capitalizing A Rbic § 4290.200 Adequate capital for RBICs. You must meet...

  5. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Responsibility for maintaining adequate safeguards. 1304.114 Section 1304.114 Energy NUCLEAR WASTE TECHNICAL REVIEW BOARD PRIVACY ACT OF 1974 § 1304.114 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining...

  6. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Adequate file search. 716.25 Section 716.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of...

  7. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  8. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  9. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  10. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  11. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  12. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  13. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  14. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  15. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Responsibility for maintaining adequate safeguards. 1304.114 Section 1304.114 Energy NUCLEAR WASTE TECHNICAL REVIEW BOARD PRIVACY ACT OF 1974 § 1304.114 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining...

  16. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Responsibility for maintaining adequate safeguards. 1304.114 Section 1304.114 Energy NUCLEAR WASTE TECHNICAL REVIEW BOARD PRIVACY ACT OF 1974 § 1304.114 Responsibility for maintaining adequate safeguards. The Board has the responsibility for maintaining...

  17. 10 CFR 503.35 - Inability to obtain adequate capital.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Inability to obtain adequate capital. 503.35 Section 503.35 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES Permanent Exemptions for New Facilities § 503.35 Inability to obtain adequate capital. (a) Eligibility. Section 212(a)(1)(D)...

  18. 10 CFR 503.35 - Inability to obtain adequate capital.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Inability to obtain adequate capital. 503.35 Section 503.35 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES Permanent Exemptions for New Facilities § 503.35 Inability to obtain adequate capital. (a) Eligibility. Section 212(a)(1)(D)...

  19. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must find... 15 Commerce and Foreign Trade 3 2011-01-01 2011-01-01 false Adequate exploration plan....

  20. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must find... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Adequate exploration plan....

  1. "Something Adequate"? In Memoriam Seamus Heaney, Sister Quinlan, Nirbhaya

    ERIC Educational Resources Information Center

    Parker, Jan

    2014-01-01

    Seamus Heaney talked of poetry's responsibility to represent the "bloody miracle", the "terrible beauty" of atrocity; to create "something adequate". This article asks, what is adequate to the burning and eating of a nun and the murderous gang rape and evisceration of a medical student? It considers Njabulo…

  2. Restoring and Maintaining Bone in Osteopenic Female Rat Skeleton. Part 1; Changes in Bone Mass and Structure

    NASA Technical Reports Server (NTRS)

    Tang, Li Ya; Jee, Webster S. S.; Ke, Hua Zhu; Kimmel, Donald B.

    1992-01-01

    This experiment contains the crucial data for the lose, restore, and maintain (LRM) concept, a practical approach for reversing existing osteoporosis. The LRM concept uses anabolic agents to restore bone mass and architecture (+ phase) and then switches to an agent with the established ability to maintain bone mass, to keep the new bone (+/- phase). The purpose of this study was to learn whether switching to an agent known chiefly for its ability to maintain existing bone mass preserves new bone induced by PGE2, in osteopenic,estrogen-depleted rats. The current study had three phases, the bone loss (-), restore (+), and maintain (+/-) phases. We ovariectomized (OX) or sham ovariectomized (sham-OX) 5.5 month-old female rats (- phase). The OX rats were treated 5 months postovariectomy with 1-6 mg PGE2, per kg/day for 75 days to restore lost cancellous bone mass (+ phase), and then PGE2, treatment was stopped and treatment began with 1 or 5 micro-g/kg of risedronate, a bisphosphonate, twice a week for 60 days (+/- phase). During the loss (-) phase, the cancellous bone volume of the proximal tibial metaphysis in the OX rat fell to 19% of initial and 30% of age-matched control levels. During the restore (+) phase, the cancellous bone volume in OX rats doubled. When PGE2 treatment was stopped, however, and no special maintenance efforts were made during the maintain (+/-) phase, the PGE2-induced cancellous bone disappeared. In contrast, the PGE2-induced cancellous bone persisted when the PGE2 treatment was followed by either a 1 or 5 micro-g treatment of risedronate per kg given twice a week for 60 days during the maintain (+/-) phase. The tibial shaft demonstrated very little cortical bone loss during the loss (-) phase in OX rats. The tibial shaft cortical bone fell some 8%. During the restore (+) phase, new cortical bone in OX rats increased by 22%. When PGE2 treatment was stopped and nothing was given during the maintain (+/-) phase, however, all but the PGE2-induced

  3. Associated among endocrine, inflammatory, and bone markers, body composition and weight loss induced bone loss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weight loss reduces co-¬morbidities of obesity but decreases bone mass. Our aims were to determine whether adequate dairy intake could prevent weight loss related bone loss and to evaluate the contribution of energy-related hormones and inflammatory markers to bone metabolism. Overweight and obese w...

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

    NASA Astrophysics Data System (ADS)

    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.

  5. Comparative Effects of Ibandronate and Paclitaxel on Immunocompetent Bone Metastasis Model

    PubMed Central

    Chung, Yoon-Sok; Kang, Ho Chul

    2015-01-01

    Purpose Bone metastasis invariably increases morbidity and mortality. This study compares the effects of ibandronate and paclitaxel on bone structure and its mechanical properties and biochemical turnover in resorption markers using an immunocompetent Walker 256-Sprague-Dawley model, which was subjected to tumor-induced osteolysis. Materials and Methods Seventy rats were divided equally into 4 groups: 1) sham group (SHAM), 2) tumor group (CANC), 3) ibandronate treated group (IBAN), and 4) paclitaxel treated group (PAC). Morphological indices [bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp)] and mechanical properties (failure load, stiffness) were evaluated after thirty days of treatment period. Bone resorption rate was analysed using serum deoxypyridinoline (Dpd) concentrations. Results Morphological indices showed that ibandronate (anti-resorptive drug) had a better effect in treating tumor-induced architectural changes in bone than paclitaxel (chemotherapeutic drug). The deterioration in bone architecture was reflected in the biomechanical properties of bone as studied with decreased failure load (Fx) and stiffness (S) of the bone on the 30th day post-surgery. Dpd concentrations were significantly lower in the IBAN group, indicating successful inhibition of bone resorption and destruction. Conclusion Ibandronate was found to be as effective as higher doses of paclitaxel in maintaining stiffness of bone. Paclitaxel treatment did not appear to inhibit osteoclast resorption, which is contrary to earlier in-vitro literature. Emphasis should be placed on the use of immunocompetent models for examining drug efficacy since it adequately reflects bone metastasis in clinical scenarios. PMID:26446649

  6. Bone metabolism during pregnancy.

    PubMed

    Salles, Jean Pierre

    2016-06-01

    During pregnancy, mineral concentrations, of calcium and phosphorus in particular, are maintained at a high level in fetal blood so that the developing skeleton may accrete adequate mineral content. The placenta actively transports minerals for this purpose. Maternal intestinal absorption increases in order to meet the fetal demand for calcium, which is only partly dependent on calcitriol. Mineral regulation is essentially dependent on parathyroid hormone (PTH) and PTH-related protein (PTHrP). The calcium-sensing receptor (CaSR) regulates PTH and PTHrP production. If calcium intake is insufficient, the maternal skeleton will undergo resorption due to PTHrP. After birth, a switch from fetal to neonatal homeostasis occurs through increase in PTH and calcitriol, and developmental adaptation of the kidneys and intestines with bone turnover contributing additional mineral to the circulation. Calcium absorption becomes progressively active and dependent on calcitriol. The postnatal skeleton can transiently present with osteoposis but adequate mineral diet usually allows full restoration. Cases of primary osteoporosis must be identified. Loss of trabecular mineral content occurs during lactation in order to provide calcium to the newborn. This programmed bone loss is dependent on a "brain-breast-bone" circuit. The physiological bone resorption during reproduction does not normally cause fractures or persistent osteoporosis. Women who experience fracture are likely to have other causes of bone loss. PMID:27157104

  7. Living Bones, Strong Bones

    NASA Video Gallery

    In this classroom activity, engineering, nutrition, and physical activity collide when students design and build a healthy bone model of a space explorer which is strong enough to withstand increas...

  8. Cell Mechanisms of Bone Tissue Loss Under Space Flight Conditions

    NASA Astrophysics Data System (ADS)

    Rodionova, Natalia

    Investigations on the space biosatellites has shown that the bone skeleton is one of the most im-portant targets of the effect space flight factors on the organism. Bone tissue cells were studied by electron microscopy in biosamples of rats' long bones flown on the board american station "SLS-2" and in experiments with modelling of microgravity ("tail suspension" method) with using autoradiography. The analysis of data permits to suppose that the processes of remod-eling in bone tissue at microgravity include the following succession of cell-to-cell interactions. Osteocytes as mechanosensory cells are first who respond to a changing "mechanical field". The next stage is intensification of osteolytic processes in osteocytes, leading to a volume en-largement of the osteocytic lacunae and removal of the "excess bone". Then mechanical signals have been transmitted through a system of canals and processes of the osteocytic syncitium to certain superficial bone zones and are perceived by osteoblasts and bone-lining cells (superficial osteocytes), as well as by the bone-marrow stromal cells. The sensitivity of stromal cells, pre-osteoblasts and osteoblasts, under microgravity was shown in a number of works. As a response to microgravity, the system of stromal cells -preosteoblasts -osteoblasts displays retardation of proliferation, differentiation and specific functions of osteogenetic cells. This is supported by the 3H-thymidine studies of the dynamics of differentiation of osteogenetic cells in remodeling zones. But unloading is not adequate and in part of the osteocytes are apoptotic changes as shown by our electron microscopic investigations. An osteocytic apoptosis can play the role in attraction the osteoclasts and in regulation of bone remodeling. The apoptotic bodies with a liquid flow through a system of canals are transferred to the bone surface, where they fulfil the role of haemoattractants for monocytes come here and form osteoclasts. The osteoclasts destroy

  9. Bone scan

    MedlinePlus

    ... scan is an imaging test used to diagnose bone diseases and find out how severe they are. How ... a 3-phase bone scan. To evaluate metastatic bone disease, images are taken only after the 3- to ...

  10. Bone Cancer

    MedlinePlus

    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 ...

  11. Bone scan

    MedlinePlus

    A bone scan is an imaging test used to diagnose bone diseases and find out how severe they are. ... A bone scan involves injecting a very small amount of radioactive material (radiotracer) into a vein. The substance travels through ...

  12. Bone Density

    MedlinePlus

    ... bone health. It compares your bone density, or mass, to that of a healthy person who is ... Whether your osteoporosis treatment is working Low bone mass that is not low enough to be osteoporosis ...

  13. Bone Tumor

    MedlinePlus

    ... most common types of primary bone cancer are: • Multiple myeloma. Multiple myeloma is the most common primary bone cancer. It ... Any bone can be affected by this cancer. Multiple myeloma affects approximately six people per 100,000 each ...

  14. Bone Cancer

    MedlinePlus

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another part of the body is more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 ...

  15. Microarchitecture of irradiated bone: comparison with healthy bone

    NASA Astrophysics Data System (ADS)

    Bléry, Pauline; Amouriq, Yves; Guédon, Jeanpierre; Pilet, Paul; Normand, Nicolas; Durand, Nicolas; Espitalier, Florent; Arlicot, Aurore; Malard, Olivier; Weiss, Pierre

    2012-03-01

    The squamous cell carcinomas of the upper aero-digestive tract represent about ten percent of cancers. External radiation therapy leads to esthetic and functional consequences, and to a decrease of the bone mechanical abilities. For these patients, the oral prosthetic rehabilitation, including possibilities of dental implant placement, is difficult. The effects of radiotherapy on bone microarchitecture parameters are not well known. Thus, the purpose of this study is to assess the effects of external radiation on bone micro architecture in an experimental model of 25 rats using micro CT. 15 rats were irradiated on the hind limbs by a single dose of 20 Grays, and 10 rats were non irradiated. Images of irradiated and healthy bone were compared. Bone microarchitecture parameters (including trabecular thickness, trabecular number, trabecular separation, connectivity density and tissue and bone volume) between irradiated and non-irradiated bones were calculated and compared using a Mann and Whitney test. After 7 and 12 weeks, images of irradiated and healthy bone are different. Differences on the irradiated and the healthy bone populations exhibit a statistical significance. Trabecular number, connectivity density and closed porosity are less important on irradiated bone. Trabecular thickness and separation increase for irradiated bone. These parameters indicate a decrease of irradiated bone properties. Finally, the external irradiation induces changes on the bone micro architecture. This knowledge is of prime importance for better oral prosthetic rehabilitation, including implant placement.

  16. Bone Metabolism on ISS Missions

    NASA Technical Reports Server (NTRS)

    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

  17. Boron and fish oil have different beneficial effects on strength and trabecular microarchitecture of bone.

    PubMed

    Nielsen, Forrest H; Stoecker, Barbara J

    2009-01-01

    An experiment was performed to determine whether boron deprivation would adversely affect vertebra (trabecular) bone microarchitecture, and whether any adverse effect would be modified by dietary fatty acid composition. Female rats were fed diets containing 0.1mg (9 micromol) boron/kg in a factorial arrangement with variables of supplemental boron at 0 (boron-deprived) or 3 (boron-adequate) mg (278 micromol)/kg and fat sources of 75 g safflower oil/kg or 65 g fish (menhaden)oil/kg plus 10 g linoleic acid/kg. After 6 weeks, six females per treatment were bred. Dams and pups continued on their respective diets through gestation, lactation, and after weaning. At age 21 weeks, the microarchitecture of the fourth lumbar vertebrae from 12 randomly selected pups from each treatment was determined by microcomputed tomography. Boron deprivation decreased bone volume fraction and increased trabecular separation and structural model index. Boron deprivation decreased trabecular thickness when the dietary oil was safflower. A three-point bending test for bone strength found that boron deprivation decreased the maximum force needed to break the femur. Feeding fish oil instead of safflower oil decreased connectivity density in vertebrae of boron-deficient but not in boron-adequate rats. Fish oil instead of safflower oil increased the maximum force to break and the bending moment of the femur, especially in rats fed adequate boron. The findings confirm that boron and fish oil are beneficial to cortical bone strength, and show that nutritional intakes of boron are beneficial for trabecular bone microarchitecture and influence the beneficial effects of fish oil on bone. PMID:19486829

  18. Arabidopsis: An Adequate Model for Dicot Root Systems?

    PubMed

    Zobel, Richard W

    2016-01-01

    The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to eight different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5) of these classes of root. This then suggests that Arabidopsis root research can be considered an adequate model for dicot plant root systems. PMID:26904040

  19. Genetic toxicity evaluation of iodotrifluoromethane (Cf{sub 3}I). Volume 2. Results of in vivo mouse bone marrow erythrocyte micronucleus testing. Final report, March-December 1994

    SciTech Connect

    Mitchell, A.D.

    1995-01-01

    Under subcontract to ManTech Environmental Technology, Incorporated, Genesys Research, Incorporated, examined the potential of odotrifluoromethane (CF3I) to induce structural chromosomes aberrations in erythropoietic cells of the bone marrow. Genesys used the mouse micronucleus test which measures the clastogenic (chromosomes breaking) action of chemicals by the induction of micronuclei in bone marrow cells, as observed in erythrocytes from the peripheral blood of male and female mice obtained approximately 24 hours after steady-state dosing. Based on preliminary toxicity information obtained by ManTech, a mouse bone marrow micronucleus test of CF3I was conducted using 2.6, 5.0, and 7.5% CF3I administered to male and female Swiss Webster mice by inhalation for six hours on each of three consecutive days. Bone marrow cells were obtained from the mice sacrificed 24 hours after the third exposure. Erythrocytes from mice exposed to the test material, and to the negative and positive controls, were evaluated for toxicity and the presence of micronuclei. The positive control, 0.4 mg triethylenemelamine (TEM)/kg (administered intraperitonealy) significantly (pbone marrow micronucleus test and clastogenic in vivo.

  20. Automated trabecular bone histomorphometry

    NASA Technical Reports Server (NTRS)

    Polig, E.; Jee, W. S. S.

    1985-01-01

    The toxicity of alpha-emitting bone-seeking radionuclides and the relationship between bone tumor incidence and the local dosimetry of radionuclides in bone are investigated. The microdistributions of alpha-emitting radionuclides in the trabecular bone from the proximal humerus, distal humerus, proximal ulna, proximal femur, and distal femur of six young adult beagles injected with Am-241 (three with 2.8 micro-Ci/kg and three with 0.9 micro-Ci/kg) are estimated using a computer-controlled microscope photometer system; the components of the University of Utah Optical Track Scanner are described. The morphometric parameters for the beagles are calculated and analyzed. It is observed that the beagles injected with 0.9 micro-Ci of Am-241/kg showed an increase in the percentage of bone and trabecular bone thickness, and a reduction in the width of the bone marrow space and surface/volume ratio. The data reveal that radiation damage causes abnormal bone structure.

  1. Implications of compromised zinc status on bone loss associated with chronic inflammation in C57BL/6 mice

    PubMed Central

    Chongwatpol, Pitipa; Rendina-Ruedy, Elizabeth; Stoecker, Barbara J; Clarke, Stephen L; Lucas, Edralin A; Smith, Brenda J

    2015-01-01

    Compromised zinc status and chronic inflammation are independent factors that can contribute to bone loss. However, zinc’s role in regulating lymphoid and myeloid cell populations, combined with the interplay between the immune and skeletal systems raises the question as to the extent to which a low-grade inflammatory challenge in the context of marginal zinc deficiency would exacerbate bone loss. To address this question, young adult C57BL/6 male mice (n=32) were used in a 2×2 factorial design with dietary zinc (adequate or 35 ppm vs inadequate or −Zn =5 ppm) and lipopolysaccharide (LPS, 0 or 0.1 mg/kg body weight). Mice were fed their respective diets for 10 weeks. On the 6th week, mice had a slow release pellet implanted to induce a low-grade inflammation for the final 4 weeks of the study. −Zn induced a decrease in total white cell counts and peripheral lymphocytes, whereas LPS increased blood monocytes. LPS significantly reduced spine bone mineral density and trabecular bone volume and number of the vertebral body compared with both zinc adequate and inadequate without LPS groups. Likewise, the most pronounced effects on bone strength occurred with LPS, however, −Zn also had negative effects on the bone von Mises stresses. LPS induced an increase in TNF-α and this response was further increased with −Zn. Although the marginal zinc deficiency altered immune function, bone loss was not exacerbated with low-grade chronic inflammation in marginally zinc-deficient young adult mice. These findings demonstrate that in young adult animals an immune challenge modestly increases the inflammatory response and worsens bone biomechanics in the context of a marginal zinc deficiency, but not to the extent that more severe adverse outcomes are observed on bone structural parameters. PMID:26203271

  2. Is the Marketing Concept Adequate for Continuing Education?

    ERIC Educational Resources Information Center

    Rittenburg, Terri L.

    1984-01-01

    Because educators have a social responsibility to those they teach, the marketing concept may not be adequate as a philosophy for continuing education. In attempting to broaden the audience for continuing education, educators should consider a societal marketing concept to meet the needs of the educationally disadvantaged. (SK)

  3. Comparability and Reliability Considerations of Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Maier, Kimberly S.; Maiti, Tapabrata; Dass, Sarat C.; Lim, Chae Young

    2012-01-01

    The purpose of this study is to develop an estimate of Adequate Yearly Progress (AYP) that will allow for reliable and valid comparisons among student subgroups, schools, and districts. A shrinkage-type estimator of AYP using the Bayesian framework is described. Using simulated data, the performance of the Bayes estimator will be compared to…

  4. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION...

  5. Understanding Your Adequate Yearly Progress (AYP), 2011-2012

    ERIC Educational Resources Information Center

    Missouri Department of Elementary and Secondary Education, 2011

    2011-01-01

    The "No Child Left Behind Act (NCLB) of 2001" requires all schools, districts/local education agencies (LEAs) and states to show that students are making Adequate Yearly Progress (AYP). NCLB requires states to establish targets in the following ways: (1) Annual Proficiency Target; (2) Attendance/Graduation Rates; and (3) Participation Rates.…

  6. Assessing Juvenile Sex Offenders to Determine Adequate Levels of Supervision.

    ERIC Educational Resources Information Center

    Gerdes, Karen E.; And Others

    1995-01-01

    This study analyzed the internal consistency of four inventories used by Utah probation officers to determine adequate and efficacious supervision levels and placement for juvenile sex offenders. Three factors accounted for 41.2 percent of variance (custodian's and juvenile's attitude toward intervention, offense characteristics, and historical…

  7. 34 CFR 200.13 - Adequate yearly progress in general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Adequate yearly progress in general. 200.13 Section 200.13 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE...

  8. 34 CFR 200.20 - Making adequate yearly progress.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Making adequate yearly progress. 200.20 Section 200.20 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE DISADVANTAGED...

  9. Do Beginning Teachers Receive Adequate Support from Their Headteachers?

    ERIC Educational Resources Information Center

    Menon, Maria Eliophotou

    2012-01-01

    The article examines the problems faced by beginning teachers in Cyprus and the extent to which headteachers are considered to provide adequate guidance and support to them. Data were collected through interviews with 25 school teachers in Cyprus, who had recently entered teaching (within 1-5 years) in public primary schools. According to the…

  10. Short bones

    MedlinePlus

    Short bones in the human body are often cube-like, their length, width, and height are all about the same. Short bones include the carpal bones of the hands and wrist, and the tarsal bones of the feet and ankles.

  11. Changes in female roles in Pakistan: are the volume and pace adequate.

    PubMed

    Shah, N M

    1986-01-01

    Cultural discrimination against women is neither a new phenomenon nor restricted to Pakistan. In Pakistan, many of the cultural traditions and norms go back to the pre-independence period and the influence of the Hindu religion on the life of the subcontinent. The institution of dowry, for example, has its roots in the centuries old traditions of the subcontinent. With Islam, this institution should have weakened, but actually the customs surrounding marriage and dowry seem to be getting more complex and expensive than before. If an objective and fair-minded exercise were carried out to define and institutionalize all the rights given to women by Islam, the situation of Pakistani women would look very different from what it is today. This exercise is complicated by 2 unfortunate facts: 1) the highly conservative interpretation of religious dictates by scholars who consider themselves to be custodians of Islam and 2) the existence of certain cultural values which make it difficult to implement and provide the rights granted to women by Islam. A step-by-step listing of all the rights given to women must, to be fair, include 1) recognizing women as complete human beings, having equal status with men; 2) defining women's roles in broader terms than those of wife and mother; and 3) giving women all the rights that were granted to them by Islam. Finally, all of the above should be accomplished without generating animosity between the sexes or weakening the family system. PMID:12280757

  12. Bone scanning.

    PubMed

    Greenfield, L D; Bennett, L R

    1975-03-01

    Scanning is based on the uptake of a nuclide by the crystal lattice of bone and is related to bone blood flow. Cancer cells do not take up the tracer. Normally, the scan visualizes the highly vascular bones. Scans are useful and are indicated in metastatic bone disease, primary bone tumors, hematologic malignancies and some non-neoplastic diseases. The scan is more sensitive than x-ray in the detection of malignant diseases of the skeleton. PMID:1054210

  13. Alveolar Ridge Preservation Using Xenogeneic Collagen Matrix and Bone Allograft

    PubMed Central

    Parashis, Andreas O.; Kalaitzakis, Charalampos J.; Tatakis, Dimitris N.; Tosios, Konstantinos

    2014-01-01

    Alveolar ridge preservation (ARP) has been shown to prevent postextraction bone loss. The aim of this report is to highlight the clinical, radiographic, and histological outcomes following use of a bilayer xenogeneic collagen matrix (XCM) in combination with freeze-dried bone allograft (FDBA) for ARP. Nine patients were treated after extraction of 18 teeth. Following minimal flap elevation and atraumatic extraction, sockets were filled with FDBA. The XCM was adapted to cover the defect and 2-3 mm of adjacent bone and flaps were repositioned. Healing was uneventful in all cases, the XCM remained in place, and any matrix exposure was devoid of further complications. Exposed matrix portions were slowly vascularized and replaced by mature keratinized tissue within 2-3 months. Radiographic and clinical assessment indicated adequate volume of bone for implant placement, with all planned implants placed in acceptable positions. When fixed partial dentures were placed, restorations fulfilled aesthetic demands without requiring further augmentation procedures. Histological and immunohistochemical analysis from 9 sites (4 patients) indicated normal mucosa with complete incorporation of the matrix and absence of inflammatory response. The XCM + FDBA combination resulted in minimal complications and desirable soft and hard tissue therapeutic outcomes, suggesting the feasibility of this approach for ARP. PMID:25328523

  14. Bone quality and bone strength: benefits of the bone-forming approach

    PubMed Central

    Iolascon, Giovanni; Frizzi, Laura; Di Pietro, Gioconda; Capaldo, Annarita; Luciano, Fabrizio; Gimigliano, Francesca

    2014-01-01

    Summary The ability of bone to resist fracture depends on the intrinsic properties of the materials that comprise the bone matrix mineralization, the amount of bone (i.e. mass), and the spatial distribution of the bone mass (i.e. microarchitecture). Antiresorptive agents may prevent the decay of cancellous bone and cortical thinning, with no improvement of bone microstructure, leading to a partial correction of the principal bone quality defect in osteoporosis, the disruption of trabecular microarchitecture. Anabolic agents promote bone formation at both trabecular and endocortical surfaces, resulting in an increase of cancellous bone volume and cortical thickness. The improvement of cortical bone strength may be limited by an increase in cortical porosity. strontium ranelate improves trabecular network and cortical thickness that will contribute to anti-fracture efficacy at both vertebral and non-vertebral sites. The results of clinical and experimental studies are consistent with the mode of action of strontium involving dissociation between bone formation and resorption leading to a stimulation both trabecular and cortical bone formation without increasing cortical porosity. PMID:25002875

  15. Bone loss in chronic kidney disease: Quantity or quality?

    PubMed

    Zheng, Cai-Mei; Zheng, Jin-Quan; Wu, Chia-Chao; Lu, Chien-Lin; Shyu, Jia-Fwu; Yung-Ho, Hsu; Wu, Mei-Yi; Chiu, I-Jen; Wang, Yuan-Hung; Lin, Yuh-Feng; Lu, Kuo-Cheng

    2016-06-01

    Chronic kidney disease (CKD) patients experience bone loss and fracture because of a specific CKD-related systemic disorder known as CKD-mineral bone disorder (CKD-MBD). The bone turnover, mineralization, and volume (TMV) system describes the morphological bone lesions in renal osteodystrophy related to CKD-MBD. Bone turnover and bone volume are defined as high, normal, or low, and bone mineralization is classified as normal or abnormal. All types of bone histology related to TMV are responsible for both bone quantity and bone quality losses in CKD patients. This review focuses on current bone quantity and bone quality losses in CKD patients and finally discusses potential therapeutic measures. PMID:27049042

  16. Onlay Bone Grafts in Head and Neck Reconstruction

    PubMed Central

    Yazar, Sukru

    2010-01-01

    Bone grafts are used in a variety of clinical situations and can be divided into two categories: treatment of bone gaps (inlay bone grafting) and bone projection (onlay bone grafting). Cortical grafts are useful in situations requiring immediate mechanical strength. These grafts can survive with or without complete revascularization or resorption and are primarily used by plastic surgeons in the treatment of bone volume deficiency. Cancellous grafts, in contrast, have no mechanical strength and therefore require additional support to bridge bone defects. Thus, they are used primarily for the treatment of bone gaps and in general revascularize quickly, resorb completely, and stimulate significant new bone formation. PMID:22550447

  17. Maintaining adequate hydration and nutrition in adult enteral tube feeding.

    PubMed

    Dunn, Sasha

    2015-01-01

    Predicting the nutritional and fluid requirements of enterally-fed patients can be challenging and the practicalities of ensuring adequate delivery must be taken into consideration. Patients who are enterally fed can be more reliant on clinicians, family members and carers to meet their nutrition and hydration needs and identify any deficiencies, excesses or problems with delivery. Estimating a patient's requirements can be challenging due to the limitations of using predictive equations in the clinical setting. Close monitoring by all those involved in the patient's care, as well as regular review by a dietitian, is therefore required to balance the delivery of adequate feed and fluids to meet each patient's individual needs and prevent the complications of malnutrition and dehydration. Increasing the awareness of the signs of malnutrition and dehydration in patients receiving enteral tube feeding among those involved in a patient's care will help any deficiencies to be detected early on and rectified before complications occur. PMID:26087203

  18. Assessing juvenile sex offenders to determine adequate levels of supervision.

    PubMed

    Gerdes, K E; Gourley, M M; Cash, M C

    1995-08-01

    The present study analyzed the internal consistency of four inventories currently being used by probation officers in the state of Utah to determine adequate and efficacious supervision levels and placement for juvenile sex offenders. The internal consistency or reliability of the inventories ranged from moderate to good. Factor analysis was utilized to significantly increase the reliability of the four inventories by collapsing them into the following three factors: (a) Custodian's and Juvenile's Attitude Toward Intervention; (b) Offense Characteristics; and (c) Historical Risk Factors. These three inventories/factors explained 41.2% of the variance in the combined inventories' scores. Suggestions are made regarding the creation of an additional inventory. "Characteristics of the Victim" to account for more of the variance. In addition, suggestions as to how these inventories can be used by probation officers to make objective and consistent decisions about adequate supervision levels and placement for juvenile sex offenders are discussed. PMID:7583754

  19. Analysis of the Effect of Race, Socioeconomic Status, and Center Size on Unrelated National Marrow Donor Program Donor Outcomes: Donor Toxicities Are More Common at Low-Volume Bone Marrow Collection Centers.

    PubMed

    Shaw, Bronwen E; Logan, Brent R; Kiefer, Deidre M; Chitphakdithai, Pintip; Pedersen, Tanya L; Abdel-Azim, Hisham; Abidi, Muneer H; Akpek, Gorgun; Diaz, Miguel A; Artz, Andrew S; Dandoy, Christopher; Gajewski, James L; Hematti, Peiman; Kamble, Rammurti T; Kasow, Kimberley A; Lazarus, Hillard M; Liesveld, Jane L; Majhail, Navneet S; O'Donnell, Paul V; Olsson, Richard F; Savani, Bipin N; Schears, Raquel M; Stroncek, David F; Switzer, Galen E; Williams, Eric P; Wingard, John R; Wirk, Baldeep M; Confer, Dennis L; Pulsipher, Michael A

    2015-10-01

    Previous studies have shown that risks of collection-related pain and symptoms are associated with sex, body mass index, and age in unrelated donors undergoing collection at National Marrow Donor Program centers. We hypothesized that other important factors (race, socioeconomic status [SES], and number of procedures at the collection center) might affect symptoms in donors. We assessed outcomes in 2726 bone marrow (BM) and 6768 peripheral blood stem cell (PBSC) donors collected between 2004 and 2009. Pain/symptoms are reported as maximum levels over mobilization and collection (PBSC) or within 2 days of collection (BM) and at 1 week after collection. For PBSC donors, race and center volumes were not associated with differences in pain/symptoms at any time. PBSC donors with high SES levels reported higher maximum symptom levels 1 week after donation (P = .017). For BM donors, black males reported significantly higher levels of pain (OR, 1.90; CI, 1.14 to 3.19; P = .015). No differences were noted by SES group. BM donors from low-volume centers reported more toxicity (OR, 2.09; CI, 1.26 to 3.46; P = .006). In conclusion, race and SES have a minimal effect on donation-associated symptoms. However, donors from centers performing ≤ 1 BM collection every 2 months have more symptoms after BM donation. Approaches should be developed by registries and low-volume centers to address this issue. PMID:26116089

  20. Low Bone Density

    MedlinePlus

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

  1. Effects of Spaceflight on Bone: The Rat as an Animal Model for Human Bone Loss

    NASA Technical Reports Server (NTRS)

    Halloran, B.; Weider, T.; Morey-Holton, E.

    1999-01-01

    The loss of weight bearing during spaceflight results in osteopenia in humans. Decrements in bone mineral reach 3-10% after as little as 75-184 days in space. Loss of bone mineral during flight decreases bone strength and increases fracture risk. The mechanisms responsible for, and the factors contributing to, the changes in bone induced by spaceflight are poorly understood. The rat has been widely used as an animal model for human bone loss during spaceflight. Despite its potential usefulness, the results of bone studies performed in the rat in space have been inconsistent. In some flights bone formation is decreased and cancellous bone volume reduced, while in others no significant changes in bone occur. In June of 1996 Drs. T. Wronski, S. Miller and myself participated in a flight experiment (STS 78) to examine the effects of glucocorticoids on bone during weightlessness. Technically the 17 day flight experiment was flawless. The results, however, were surprising. Cancellous bone volume and osteoblast surface in the proximal tibial metaphysis were the same in flight and ground-based control rats. Normal levels of cancellous bone mass and bone formation were also detected in the lumbar vertebrae and femoral neck of flight rats. Furthermore, periosteal bone formation rate was found to be identical in flight and ground-based control rats. Spaceflight had little or no effect on bone metabolism! These results prompted us to carefully review the changes in bone observed in, and the flight conditions of previous spaceflight missions.

  2. Identity, proliferation capacity, genomic stability and novel senescence markers of mesenchymal stem cells isolated from low volume of human bone marrow.

    PubMed

    Kundrotas, Gabrielis; Gasperskaja, Evelina; Slapsyte, Grazina; Gudleviciene, Zivile; Krasko, Jan; Stumbryte, Ausra; Liudkeviciene, Regina

    2016-03-01

    Human bone marrow mesenchymal stem cells (hBM-MSCs) hold promise for treating incurable diseases and repairing of damaged tissues. However, hBM-MSCs face the disadvantages of painful invasive isolation and limited cell numbers. In this study we assessed characteristics of MSCs isolated from residual human bone marrow transplantation material and expanded to clinically relevant numbers at passages 3-4 and 6-7. Results indicated that early passage hBM-MSCs are genomically stable and retain identity and high proliferation capacity. Despite the chromosomal stability, the cells became senescent at late passages, paralleling the slower proliferation, altered morphology and immunophenotype. By qRT-PCR array profiling, we revealed 13 genes and 33 miRNAs significantly differentially expressed in late passage cells, among which 8 genes and 30 miRNAs emerged as potential novel biomarkers of hBM-MSC aging. Functional analysis of genes with altered expression showed strong association with biological processes causing cellular senescence. Altogether, this study revives hBM as convenient source for cellular therapy. Potential novel markers provide new details for better understanding the hBM-MSC senescence mechanisms, contributing to basic science, facilitating the development of cellular therapy quality control, and providing new clues for human disease processes since senescence phenotype of the hematological patient hBM-MSCs only very recently has been revealed. PMID:26910916

  3. Identity, proliferation capacity, genomic stability and novel senescence markers of mesenchymal stem cells isolated from low volume of human bone marrow

    PubMed Central

    Kundrotas, Gabrielis; Gasperskaja, Evelina; Slapsyte, Grazina; Gudleviciene, Zivile; Krasko, Jan; Stumbryte, Ausra; Liudkeviciene, Regina

    2016-01-01

    Human bone marrow mesenchymal stem cells (hBM-MSCs) hold promise for treating incurable diseases and repairing of damaged tissues. However, hBM-MSCs face the disadvantages of painful invasive isolation and limited cell numbers. In this study we assessed characteristics of MSCs isolated from residual human bone marrow transplantation material and expanded to clinically relevant numbers at passages 3-4 and 6-7. Results indicated that early passage hBM-MSCs are genomically stable and retain identity and high proliferation capacity. Despite the chromosomal stability, the cells became senescent at late passages, paralleling the slower proliferation, altered morphology and immunophenotype. By qRT-PCR array profiling, we revealed 13 genes and 33 miRNAs significantly differentially expressed in late passage cells, among which 8 genes and 30 miRNAs emerged as potential novel biomarkers of hBM-MSC aging. Functional analysis of genes with altered expression showed strong association with biological processes causing cellular senescence. Altogether, this study revives hBM as convenient source for cellular therapy. Potential novel markers provide new details for better understanding the hBM-MSC senescence mechanisms, contributing to basic science, facilitating the development of cellular therapy quality control, and providing new clues for human disease processes since senescence phenotype of the hematological patient hBM-MSCs only very recently has been revealed. PMID:26910916

  4. Symmetry analysis of talus bone

    PubMed Central

    Islam, K.; Dobbe, A.; Komeili, A.; Duke, K.; El-Rich, M.; Dhillon, S.; Adeeb, S.; Jomha, N. M.

    2014-01-01

    Objective The main object of this study was to use a geometric morphometric approach to quantify the left-right symmetry of talus bones. Methods Analysis was carried out using CT scan images of 11 pairs of intact tali. Two important geometric parameters, volume and surface area, were quantified for left and right talus bones. The geometric shape variations between the right and left talus bones were also measured using deviation analysis. Furthermore, location of asymmetry in the geometric shapes were identified. Results Numerical results showed that talus bones are bilaterally symmetrical in nature, and the difference between the surface area of the left and right talus bones was less than 7.5%. Similarly, the difference in the volume of both bones was less than 7.5%. Results of the three-dimensional (3D) deviation analyses demonstrated the mean deviation between left and right talus bones were in the range of -0.74 mm to 0.62 mm. It was observed that in eight of 11 subjects, the deviation in symmetry occurred in regions that are clinically less important during talus surgery. Conclusions We conclude that left and right talus bones of intact human ankle joints show a strong degree of symmetry. The results of this study may have significance with respect to talus surgery, and in investigating traumatic talus injury where the geometric shape of the contralateral talus can be used as control. Cite this article: Bone Joint Res 2014;3:139–45. PMID:24802391

  5. Estimation of adequate setup margins and threshold for position errors requiring immediate attention in head and neck cancer radiotherapy based on 2D image guidance

    PubMed Central

    2013-01-01

    Background We estimated sufficient setup margins for head-and-neck cancer (HNC) radiotherapy (RT) when 2D kV images are utilized for routine patient setup verification. As another goal we estimated a threshold for the displacements of the most important bony landmarks related to the target volumes requiring immediate attention. Methods We analyzed 1491 orthogonal x-ray images utilized in RT treatment guidance for 80 HNC patients. We estimated overall setup errors and errors for four subregions to account for patient rotation and deformation: the vertebrae C1-2, C5-7, the occiput bone and the mandible. Setup margins were estimated for two 2D image guidance protocols: i) imaging at first three fractions and weekly thereafter and ii) daily imaging. Two 2D image matching principles were investigated: i) to the vertebrae in the middle of planning target volume (PTV) (MID_PTV) and ii) minimizing maximal position error for the four subregions (MIN_MAX). The threshold for the position errors was calculated with two previously unpublished methods based on the van Herk’s formula and clinical data by retaining a margin of 5 mm sufficient for each subregion. Results Sufficient setup margins to compensate the displacements of the subregions were approximately two times larger than were needed to compensate setup errors for rigid target. Adequate margins varied from 2.7 mm to 9.6 mm depending on the subregions related to the target, applied image guidance protocol and early correction of clinically important systematic 3D displacements of the subregions exceeding 4 mm. The MIN_MAX match resulted in smaller margins but caused an overall shift of 2.5 mm for the target center. Margins ≤ 5mm were sufficient with the MID_PTV match only through application of daily 2D imaging and the threshold of 4 mm to correct systematic displacement of a subregion. Conclusions Adequate setup margins depend remarkably on the subregions related to the target volume. When the systematic 3D

  6. Bone Markers

    MedlinePlus

    ... Alkaline Phosphatase; Osteocalcin; P1NP; Procollagen Type 1 N-Terminal Propeptide Formal name: Biochemical Markers of Bone Remodeling ... tests for evaluating bone turnover: C-telopeptide (C-terminal telopeptide of type 1 collagen (CTx)) – a marker ...

  7. Bone tumor

    MedlinePlus

    ... physical exam. Tests that may be done include: Alkaline phosphatase blood level Bone biopsy Bone scan Chest x- ... also affect the results of the following tests: Alkaline phosphatase isoenzyme Blood calcium level Parathyroid hormone Blood phosphorus ...

  8. Bone Infections

    MedlinePlus

    ... of the body, bones can get infected. The infections are usually bacterial, but can also be fungal. ... bloodstream. People who are at risk for bone infections include those with diabetes, poor circulation, or recent ...

  9. Adequation of mini satellites to oceanic altimetry missions

    NASA Astrophysics Data System (ADS)

    Bellaieche, G.; Aguttes, J. P.

    1993-01-01

    Association of the mini satellite concept and oceanic altimetry missions is discussed. Mission definition and most constraining requirements (mesoscale for example) demonstrate mini satellites to be quite adequate for such missions. Progress in altimeter characteristics, orbit determination, and position reporting allow consideration of oceanic altimetry missions using low Earth orbit satellites. Satellite constellation, trace keeping and orbital period, and required payload characteristics are exposed. The mission requirements covering Sun synchronous orbit, service area, ground system, and launcher characteristics as well as constellation maintenance strategy are specified. Two options for the satellite, orbital mechanics, propulsion, onboard power and stabilizing subsystems, onboard management, satellite ground linkings, mechanical and thermal subsystems, budgets, and planning are discussed.

  10. Bone cement

    PubMed Central

    Vaishya, Raju; Chauhan, Mayank; Vaish, Abhishek

    2013-01-01

    The knowledge about the bone cement is of paramount importance to all Orthopaedic surgeons. Although the bone cement had been the gold standard in the field of joint replacement surgery, its use has somewhat decreased because of the advent of press-fit implants which encourages bone in growth. The shortcomings, side effects and toxicity of the bone cement are being addressed recently. More research is needed and continues in the field of nanoparticle additives, enhanced bone–cement interface etc. PMID:26403875

  11. Bone Analyzer

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The danger of disuse osteoporosis under weightless condition in space led to extensive research into measurements of bone stiffness and mass by the Biomedical Research Division of Ames and Stanford University. Through its Technology Utilization Program, NASA funded an advanced SOBSA, a microprocessor-controlled bone probe system. SOBSA determines bone stiffness by measuring responses to an electromagnetic shaker. With this information, a physician can identify bone disease, measure deterioration and prescribe necessary therapy. The system is now undergoing further testing.

  12. Vitamin E provides protection for bone in mature hindlimb unloaded male rats

    NASA Technical Reports Server (NTRS)

    Smith, B. J.; Lucas, E. A.; Turner, R. T.; Evans, G. L.; Lerner, M. R.; Brackett, D. J.; Stoecker, B. J.; Arjmandi, B. H.

    2005-01-01

    The deleterious effects of skeletal unloading on bone mass and strength may, in part, result from increased production of oxygen-derived free radicals and proinflammatory cytokines. This study was designed to evaluate the ability of vitamin E (alpha-tocopherol), a free-radical scavenger with antiinflammatory properties, to protect against bone loss caused by skeletal unloading in mature male Sprague-Dawley rats. A 2 x 3 factorial design was used with either hindlimb unloading (HU) or normal loading (ambulatory; AMB), and low-dose (LD; 15 IU/kg diet), adequate-dose (AD; 75 IU/kg diet), or high-dose (HD; 500 IU/kg diet) vitamin E (DL-alpha-tocopherol acetate). To optimize the effects of vitamin E on bone, dietary treatments were initiated 9 weeks prior to unloading and continued during the 4-week unloading period, at which time animals were euthanized and blood and tissue samples were collected. Serum vitamin E was dose-dependently increased, confirming the vitamin E status of animals. The HD treatment improved oxidation parameters, as indicated by elevated serum ferric-reducing ability and a trend toward reducing tissue lipid peroxidation. Histomorphometric analysis of the distal femur revealed significant reductions in trabecular thickness (TbTh), double-labeled surface (dLS/BS), and rate of bone formation to bone volume (BFR/BV) due by HU. AMB animals on the HD diet and HU animals on the LD diet had reduced bone surface normalized to tissue volume (BS/TV) and trabecular number (TbN); however, the HD vitamin E protected against these changes in the HU animals. Our findings suggest that vitamin E supplementation provides modest bone protective effects during skeletal unloading.

  13. Quantifying dose to the reconstructed breast: Can we adequately treat?

    SciTech Connect

    Chung, Eugene; Marsh, Robin B.; Griffith, Kent A.; Moran, Jean M.; Pierce, Lori J.

    2013-04-01

    To evaluate how immediate reconstruction (IR) impacts postmastectomy radiotherapy (PMRT) dose distributions to the reconstructed breast (RB), internal mammary nodes (IMN), heart, and lungs using quantifiable dosimetric end points. 3D conformal plans were developed for 20 IR patients, 10 autologous reconstruction (AR), and 10 expander-implant (EI) reconstruction. For each reconstruction type, 5 right- and 5 left-sided reconstructions were selected. Two plans were created for each patient, 1 with RB coverage alone and 1 with RB + IMN coverage. Left-sided EI plans without IMN coverage had higher heart Dmean than left-sided AR plans (2.97 and 0.84 Gy, p = 0.03). Otherwise, results did not vary by reconstruction type and all remaining metrics were evaluated using a combined AR and EI dataset. RB coverage was adequate regardless of laterality or IMN coverage (Dmean 50.61 Gy, D95 45.76 Gy). When included, IMN Dmean and D95 were 49.57 and 40.96 Gy, respectively. Mean heart doses increased with left-sided treatment plans and IMN inclusion. Right-sided treatment plans and IMN inclusion increased mean lung V{sub 20}. Using standard field arrangements and 3D planning, we observed excellent coverage of the RB and IMN, regardless of laterality or reconstruction type. Our results demonstrate that adequate doses can be delivered to the RB with or without IMN coverage.

  14. Purchasing a cycle helmet: are retailers providing adequate advice?

    PubMed Central

    Plumridge, E.; McCool, J.; Chetwynd, J.; Langley, J. D.

    1996-01-01

    OBJECTIVES: The aim of this study was to examine the selling of cycle helmets in retail stores with particular reference to the adequacy of advice offered about the fit and securing of helmets. METHODS: All 55 retail outlets selling cycle helmets in Christchurch, New Zealand were studied by participant observation. A research entered each store as a prospective customer and requested assistance to purchase a helmet. She took detailed field notes of the ensuing encounter and these were subsequently transcribed, coded, and analysed. RESULTS: Adequate advice for helmet purchase was given in less than half of the stores. In general the sales assistants in specialist cycle shops were better informed and gave more adequate advice than those in department stores. Those who have good advice also tended to be more good advice also tended to be more active in helping with fitting the helmet. Knowledge about safety standards was apparent in one third of sales assistants. Few stores displayed information for customers about the correct fit of cycle helmets. CONCLUSIONS: These findings suggest that the advice and assistance being given to ensure that cycle helmets fit properly is often inadequate and thus the helmets may fail to fulfil their purpose in preventing injury. Consultation between retailers and policy makers is a necessary first step to improving this situation. PMID:9346053

  15. Adequate drainage system design for heap leaching structures.

    PubMed

    Majdi, Abbas; Amini, Mehdi; Nasab, Saeed Karimi

    2007-08-17

    The paper describes an optimum design of a drainage system for a heap leaching structure which has positive impacts on both mine environment and mine economics. In order to properly design a drainage system the causes of an increase in the acid level of the heap which in turn produces severe problems in the hydrometallurgy processes must be evaluated. One of the most significant negative impacts induced by an increase in the acid level within a heap structure is the increase of pore acid pressure which in turn increases the potential of a heap-slide that may endanger the mine environment. In this paper, initially the thickness of gravelly drainage layer is determined via existing empirical equations. Then by assuming that the calculated thickness is constant throughout the heap structure, an approach has been proposed to calculate the required internal diameter of the slotted polyethylene pipes which are used for auxiliary drainage purposes. In order to adequately design this diameter, the pipe's cross-sectional deformation due to stepped heap structure overburden pressure is taken into account. Finally, a design of an adequate drainage system for the heap structure 2 at Sarcheshmeh copper mine is presented and the results are compared with those calculated by exiting equations. PMID:17321044

  16. [Nutrition in bone growth and development].

    PubMed

    Hirota, Takako; Hirota, Kenji

    2011-09-01

    The greatest increase in bone density was observed around ages 10-14 years in girls and thereafter peak bone mass was attained. Maximizing peak bone mass during adolescence is one of the most important strategies to decrease osteoporotic fractures later in life. Initial bone mass adjusted by height and weight in 10-year-old girl was associated positively with intakes of dairy products and small fish. Annual increase in bone mass from age 10 years to 11 years was associated positively with increased intake of fish, fruit, vegetables, and soybeans. Thus, not only calcium but also adequate dietary patterns such as increased intake of fish, fruit, vegetables, and soy products lead to higher peak bone mass in adolescent and will decrease the risk of bone fracture in postmenopausal age. PMID:21881195

  17. Imaging of the muscle-bone relationship.

    PubMed

    Ireland, Alex; Ferretti, José Luis; Rittweger, Jörn

    2014-12-01

    Muscle can be assessed by imaging techniques according to its size (as thickness, area, volume, or alternatively, as a mass) and architecture (fiber length and pennation angle), with values used as an anthropometric measure or a surrogate for force production. Similarly, the size of the bone (as area or volume) can be imaged using MRI or pQCT, although typically bone mineral mass is reported. Bone imaging measures of mineral density, size, and geometry can also be combined to calculate bone's structural strength-measures being highly predictive of bone's failure load ex vivo. Imaging of muscle-bone relationships can, hence, be accomplished through a number of approaches by adoption and comparison of these different muscle and bone parameters, dependent on the research question under investigation. These approaches have revealed evidence of direct, mechanical muscle-bone interactions independent of allometric associations. They have led to important information on bone mechanoadaptation and the influence of muscular action on bone, in addition to influences of age, gender, exercise, and disuse on muscle-bone relationships. Such analyses have also produced promising diagnostic tools for clinical use, such as identification of primary, disuse-induced, and secondary osteoporosis and estimation of bone safety factors. Standardization of muscle-bone imaging methods is required to permit more reliable comparisons between studies and differing imaging modes, and in particular to aid adoption of these methods into widespread clinical practice. PMID:25095743

  18. Are PPS payments adequate? Issues for updating and assessing rates

    PubMed Central

    Sheingold, Steven H.; Richter, Elizabeth

    1992-01-01

    Declining operating margins under Medicare's prospective payment system (PPS) have focused attention on the adequacy of payment rates. The question of whether annual updates to the rates have been too low or cost increases too high has become important. In this article we discuss issues relevant to updating PPS rates and judging their adequacy. We describe a modification to the current framework for recommending annual update factors. This framework is then used to retrospectively assess PPS payment and cost growth since 1985. The preliminary results suggest that current rates are more than adequate to support the cost of efficient care. Also discussed are why using financial margins to evaluate rates is problematic and alternative methods that might be employed. PMID:10127450

  19. Skeletal Blood Flow in Bone Repair and Maintenance

    PubMed Central

    Tomlinson, Ryan E.; Silva, Matthew J.

    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 anatomy, 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. PMID:26273509

  20. Bone marrow aspiration

    PubMed Central

    Bain, B

    2001-01-01

    Bone marrow aspiration biopsies are carried out principally to permit cytological assessment but also for immunophenotypic, cytogenetic, molecular genetic, and other specialised investigations. Often, a trephine biopsy is carried out as part of the same procedure. Bone marrow aspirations should be carried out by trained individuals who are aware of the indications, contraindications, and hazards of the procedure. They should follow a standard operating procedure. The operator should have made an adequate assessment of clinical and haematological features to ensure both that appropriate indications exist and that all relevant tests are performed. For the patient's comfort and safety, the posterior iliac crest is generally the preferred site of aspiration. Films of aspirated marrow and, when appropriate, films of crushed particles should be made and labelled. Once thoroughly dry, films should be fixed and stained. As a minimum, a Romanowsky stain and a Perls' stain are required. A cover slip should be applied. The bone marrow films should be assessed and reported in a systematic manner so that nothing of importance is overlooked, using a low power, then intermediate, then high power objective. A differential count should be performed. An interpretation of the findings, in the light of the clinical and haematological features, should be given. The report should be signed or computer authorised, using a secure password, and issued in a timely manner. Key Words: bone marrow aspirate • haematological diagnosis PMID:11533068

  1. The nucleocytoplasmic shuttling protein CIZ reduces adult bone mass by inhibiting bone morphogenetic protein-induced bone formation.

    PubMed

    Morinobu, Mikihiko; Nakamoto, Tetsuya; Hino, Kazunori; Tsuji, Kunikazu; Shen, Zhong-Jian; Nakashima, Kazuhisa; Nifuji, Akira; Yamamoto, Haruyasu; Hirai, Hisamaru; Noda, Masaki

    2005-03-21

    Osteoporosis is a major health problem; however, the mechanisms regulating adult bone mass are poorly understood. Cas-interacting zinc finger protein (CIZ) is a nucleocytoplasmic shuttling protein that localizes at cell adhesion plaques that form where osteoblasts attach to substrate. To investigate the potential role of CIZ in regulating adult bone mass, we examined the bones in CIZ-deficient mice. Bone volume was increased and the rates of bone formation were increased in CIZ-deficient mice, whereas bone resorption was not altered. CIZ deficiency enhanced the levels of mRNA expression of genes encoding proteins related to osteoblastic phenotypes, such as alkaline phosphatase (ALP) as well as osterix mRNA expression in whole long bones. Bone marrow cells obtained from the femora of CIZ-deficient mice revealed higher ALP activity in culture and formed more mineralized nodules than wild-type cells. CIZ deficiency enhanced bone morphogenetic protein (BMP)-induced osteoblastic differentiation in bone marrow cells in cultures, indicating that BMP is the target of CIZ action. CIZ deficiency increased newly formed bone mass after femoral bone marrow ablation in vivo. Finally, BMP-2-induced bone formation on adult mouse calvariae in vivo was enhanced by CIZ deficiency. These results establish that CIZ suppresses the levels of adult bone mass through inhibition of BMP-induced activation of osteoblasts. PMID:15781586

  2. Evaluation and utility of new CE marked containers (CELLFLEX-MacoPharma) for bone bank.

    PubMed

    Villalba, R; Fornés, G; Dueñas, R; García, A; Ariza, A; Gómez-Villagrán, J L

    2004-01-01

    In order to guarantee the required level of quality for our Bone &Tissue Banking, we evaluated a new CE marked container (CELLFLEX MacoPharma), for packing, transport, processing and storage of bones for therapeutic use. The use of CE marked containers is mandatory for organ and tissue containers (Medical Device Directive 93/42). We carried out a three-phase study: (1)Evaluation, (2) Implementation, (3)Audit The product was evaluated for the following criteria:Dash mechanical resistance, Dash air tightness, Dash fragility, Dash capacity. No damage was observed after the storage period, even after immersion in liquid nitrogen. No breakages were observed after provoked impact tests (pots dropped onto the floor). The pot capacity evaluation showed that the inner pot volume (approximately 500 ml) permits adequate storage of tendons and the majority of bone allografts. In conclusion, this evaluation has shown that the CELLFLEX kit is suitable for long duration preservation of bone allografts even at very low temperature conditions (vapour phase nitrogen). Its format and structure permit preservation of most bone allografts. PMID:15591830

  3. Fruits and dietary phytochemicals in bone protection.

    PubMed

    Shen, Chwan-Li; von Bergen, Vera; Chyu, Ming-Chien; Jenkins, Marjorie R; Mo, Huanbiao; Chen, Chung-Hwan; Kwun, In-Sook

    2012-12-01

    Osteoporosis is a disease of bone characterized by loss of bone matrix and deterioration of bone microstructure that leads to an increased risk of fracture. Cross-sectional studies have shown a positive association between higher fruit intake and higher bone mineral density. In this review, we evaluated animal and cellular studies of dried plum and citrus and berry fruits and bioactive compounds including lycopene, phenolics, favonoids, resveratrol, phloridzin, and pectin derived from tomato, grapes, apples, and citrus fruits. In addition, human studies of dried plum and lycopene were reviewed. Animal studies strongly suggest that commonly consumed antioxidant-rich fruits have a pronounced effect on bone, as shown by higher bone mass, trabecular bone volume, number, and thickness, and lower trabecular separation through enhancing bone formation and suppressing bone resorption, resulting in greater bone strength. Such osteoprotective effects seem to be mediated via antioxidant or anti-inflammatory pathways and their downstream signaling mechanisms, leading to osteoblast mineralization and osteoclast inactivation. In future studies, randomized controlled trials are warranted to extend the bone-protective activity of fruits and their bioactive compounds. Mechanistic studies are needed to differentiate the roles of phytochemicals and other constitutes in bone protection offered by the fruits. Advanced imaging technology will determine the effective doses of phytochemicals and their metabolites in improving bone mass, microarchitecture integrity, and bone strength, which is a critical step in translating the benefits of fruit consumption on osteoporosis into clinical data. PMID:23244535

  4. Chitosan-poly(butylene succinate) scaffolds and human bone marrow stromal cells induce bone repair in a mouse calvaria model.

    PubMed

    Costa-Pinto, A R; Correlo, V M; Sol, P C; Bhattacharya, M; Srouji, S; Livne, E; Reis, R L; Neves, N M

    2012-01-01

    Tissue engineering sustains the need of a three-dimensional (3D) scaffold to promote the regeneration of tissues in volume. Usually, scaffolds are seeded with an adequate cell population, allowing their growth and maturation upon implantation in vivo. Previous studies obtained by our group evidenced significant growth patterns and osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) when seeded and cultured on melt-based porous chitosan fibre mesh scaffolds (cell constructs). Therefore, it is crucial to test the in vivo performance of these in vitro 3D cell constructs. In this study, chitosan-based scaffolds were seeded and cultured in vitro with hBMSCs for 3 weeks under osteogenic stimulation conditions and analysed for cell adhesion, proliferation and differentiation. Implantation of 2 weeks precultured cell constructs in osteogenic culture conditions was performed into critical cranial size defects in nude mice. The objective of this study was to verify the scaffold integration and new bone formation. At 8 weeks of implantation, scaffolds were harvested and prepared for micro-computed tomography (µCT) analysis. Retrieved implants showed good integration with the surrounding tissue and significant bone formation, more evident for the scaffolds cultured and implanted with human cells. The results of this work demonstrated that chitosan-based scaffolds, besides supporting in vitro proliferation and osteogenic differentiation of hBMSCs, induced bone formation in vivo. Thus, their osteogenic potential in orthotopic location in immunodeficient mice was validated, evidencing good prospects for their use in bone tissue-engineering therapies. PMID:21312336

  5. Effects of cortical bone perforation on experimental guided bone regeneration.

    PubMed

    Nishimura, Ichiro; Shimizu, Yoshinaka; Ooya, Kiyoshi

    2004-06-01

    This study was designed to evaluate the effects of cortical bone perforation histologically and histomorphometrically on guided bone regeneration (GBR) in rabbits. After elimination of the periosteum, cortical bone defects of two sizes were made in the external cortical plate of the frontal bone (Group A: 1 x 15 mm; Group B: 3 x 15 mm). A non-resorbable membrane filled with autogenous blood was placed in the experimental area and secured with titanium pins. After 1 and 2 weeks, vascularized connective tissue and new bone were generated in the space surrounding the defects in both the groups. The amount of vascularized connective tissue generated in Group B was greater than that in Group A at 1 week. Alkaline phosphatase (ALP) was expressed on the bone surrounding the perforation. The expression of ALP was more extensive in Group B than in Group A and was proportional to the breadth of perforation. At 2 weeks, the perforated region was almost covered with new bone in Group A. ALP was expressed at the periphery of newly formed bone. The expression of ALP was proportional to the breadth and height of perforation. At 6 weeks, semicircular outgrowth of bone towards the periphery of the perforated region was observed in both the groups. Newly formed bone volume and ALP expression in Group B were more extensive than those in Group A. At 12 weeks, the space was filled with bone and connective tissue in both the groups. There was no difference in ALP expression between Groups A and B. Histomorphometric analysis showed significant differences between both the groups (two-way ANOVA, P<0.01). We conclude that a larger perforation is associated with prompter bone formation in the secluded space during GBR. PMID:15142091

  6. Protein intake and bone health.

    PubMed

    Bonjour, Jean-Philippe

    2011-03-01

    Adequate nutrition plays an important role in the development and maintenance of bone structures resistant to usual mechanical stresses. In addition to calcium in the presence of an adequate supply of vitamin D, dietary proteins represent key nutrients for bone health and thereby function in the prevention of osteoporosis. Several studies point to a positive effect of high protein intake on bone mineral density or content. This fact is associated with a significant reduction in hip fracture incidence, as recorded in a large prospective study carried out in a homogeneous cohort of postmenopausal women. Low protein intake (< 0.8 g/kg body weight/day) is often observed in patients with hip fractures and an intervention study indicates that following orthopedic management, protein supplementation attenuates post-fracture bone loss, tends to increase muscle strength, and reduces medical complications and rehabilitation hospital stay. There is no evidence that high protein intake per se would be detrimental for bone mass and strength. Nevertheless, it appears reasonable to avoid very high protein diets (i. e. more than 2.0 g/kg body weight/day) when associated with low calcium intake (i. e. less than 600 mg/day). In the elderly, taking into account the attenuated anabolic response to dietary protein with ageing, there is concern that the current dietary protein recommended allowance (RDA), as set at 0.8 g/kg body weight/day, might be too low for the primary and secondary prevention of fragility fractures. PMID:22139564

  7. [Bone diseases].

    PubMed

    Uebelhart, Brigitte; Rizzoli, René

    2016-01-13

    Calcium intake shows a small impact on bone mineral density and fracture risk. Denosumab is a more potent inhibitor of bone resorption than zoledronate. Abaloparatide, PTHrP analog, increases bone mineral density and decreases fracture incidence. Teriparatide could be delivered via a transdermic device. Romosozumab and odanacatib improve calculated bone strength. Sequential or combined treatments with denosumab and teriparatide could be of interest, but not denosumab followed by teriparatide. Fibrous dysplasia, Paget disease and hypophosphatasia are updated, as well as atypical femoral fracture and osteonecrosis of the jaw. PMID:26946704

  8. Dose Limits for Man do not Adequately Protect the Ecosystem

    SciTech Connect

    Higley, Kathryn A.; Alexakhin, Rudolf M.; McDonald, Joseph C.

    2004-08-01

    It has been known for quite some time that different organisms display differing degrees of sensitivity to the effects of ionizing radiations. Some microorganisms such as the bacterium Micrococcus radiodurans, along with many species of invertebrates, are extremely radio-resistant. Humans might be categorized as being relatively sensitive to radiation, and are a bit more resistant than some pine trees. Therefore, it could be argued that maintaining the dose limits necessary to protect humans will also result in the protection of most other species of flora and fauna. This concept is usually referred to as the anthropocentric approach. In other words, if man is protected then the environment is also adequately protected. The ecocentric approach might be stated as; the health of humans is effectively protected only when the environment is not unduly exposed to radiation. The ICRP is working on new recommendations dealing with the protection of the environment, and this debate should help to highlight a number of relevant issues concerning that topic.

  9. ENSURING ADEQUATE SAFETY WHEN USING HYDROGEN AS A FUEL

    SciTech Connect

    Coutts, D

    2007-01-22

    Demonstration projects using hydrogen as a fuel are becoming very common. Often these projects rely on project-specific risk evaluations to support project safety decisions. This is necessary because regulations, codes, and standards (hereafter referred to as standards) are just being developed. This paper will review some of the approaches being used in these evolving standards, and techniques which demonstration projects can implement to bridge the gap between current requirements and stakeholder desires. Many of the evolving standards for hydrogen-fuel use performance-based language, which establishes minimum performance and safety objectives, as compared with prescriptive-based language that prescribes specific design solutions. This is being done for several reasons including: (1) concern that establishing specific design solutions too early will stifle invention, (2) sparse performance data necessary to support selection of design approaches, and (3) a risk-adverse public which is unwilling to accept losses that were incurred in developing previous prescriptive design standards. The evolving standards often contain words such as: ''The manufacturer shall implement the measures and provide the information necessary to minimize the risk of endangering a person's safety or health''. This typically implies that the manufacturer or project manager must produce and document an acceptable level of risk. If accomplished using comprehensive and systematic process the demonstration project risk assessment can ease the transition to widespread commercialization. An approach to adequately evaluate and document the safety risk will be presented.

  10. DARHT - an `adequate` EIS: A NEPA case study

    SciTech Connect

    Webb, M.D.

    1997-08-01

    The Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility Environmental Impact Statement (EIS) provides a case study that is interesting for many reasons. The EIS was prepared quickly, in the face of a lawsuit, for a project with unforeseen environmental impacts, for a facility that was deemed urgently essential to national security. Following judicial review the EIS was deemed to be {open_quotes}adequate.{close_quotes} DARHT is a facility now being built at Los Alamos National Laboratory (LANL) as part of the Department of Energy (DOE) nuclear weapons stockpile stewardship program. DARHT will be used to evaluate the safety and reliability of nuclear weapons, evaluate conventional munitions and study high-velocity impact phenomena. DARHT will be equipped with two accelerator-driven, high-intensity X-ray machines to record images of materials driven by high explosives. DARHT will be used for a variety of hydrodynamic tests, and DOE plans to conduct some dynamic experiments using plutonium at DARHT as well.

  11. Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness - A Case Study on Osteoporosis Rat Bone.

    PubMed

    Wu, Yuchin; Adeeb, Samer; Doschak, Michael R

    2015-01-01

    Micro-computed tomography (Micro-CT) images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone microarchitectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA) can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of Micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived grayscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two- and three-dimensional bone microarchitecture from sham and ovariectomized (OVX) rats (n = 10/group). A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA, because Micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three-dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation, and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading. PMID:26042089

  12. Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness – A Case Study on Osteoporosis Rat Bone

    PubMed Central

    Wu, Yuchin; Adeeb, Samer; Doschak, Michael R.

    2015-01-01

    Micro-computed tomography (Micro-CT) images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone microarchitectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA) can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of Micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived grayscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two- and three-dimensional bone microarchitecture from sham and ovariectomized (OVX) rats (n = 10/group). A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA, because Micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three-dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation, and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading. PMID:26042089

  13. Experiment K305: Quantitative analysis of selected bone parameters

    NASA Technical Reports Server (NTRS)

    Wrongski, T. J.; Morey-Holton, E.; Cann, C. E.; Arnaud, C. D.; Baylink, D. J.; Turner, R. T.; Jee, W. S. S.

    1981-01-01

    The skeletal alterations induced by space flight were determined to be a reduced rate of periosteal bone formation in tibial and humeral diaphyses, a decreased trabecular bone volume, and an increased fat content of the bone marrow in the proximal tibial metaphysis. An increased incidence of arrest lines in flight animals suggested that periosteal bone formation may have ceased during space flight. Endosteal bone resorption was not affected markedly.

  14. Adequate iodine levels in healthy pregnant women. A cross-sectional survey of dietary intake in Turkey

    PubMed Central

    Kasap, Burcu; Akbaba, Gülhan; Yeniçeri, Emine N.; Akın, Melike N.; Akbaba, Eren; Öner, Gökalp; Turhan, Nilgün Ö.; Duru, Mehmet E.

    2016-01-01

    Objectives: To assess current iodine levels and related factors among healthy pregnant women. Methods: In this cross-sectional, hospital-based study, healthy pregnant women (n=135) were scanned for thyroid volume, provided urine samples for urinary iodine concentration and completed a questionnaire including sociodemographic characteristics and dietary habits targeted for iodine consumption at the Department of Obstetrics and Gynecology, School of Medicine, Muğla Sıtkı Koçman University, Muğla, Turkey, between August 2014 and February 2015. Sociodemographic data were analyzed by simple descriptive statistics. Results: Median urinary iodine concentration was 222.0 µg/L, indicating adequate iodine intake during pregnancy. According to World Health Organization (WHO) criteria, 28.1% of subjects had iodine deficiency, 34.1% had adequate iodine intake, 34.8% had more than adequate iodine intake, and 3.0% had excessive iodine intake during pregnancy. Education level, higher monthly income, current employment, consuming iodized salt, and adding salt to food during, or after cooking were associated with higher urinary iodine concentration. Conclusion: Iodine status of healthy pregnant women was adequate, although the percentage of women with more than adequate iodine intake was higher than the reported literature. PMID:27279519

  15. Histomorphometric study of alveolar bone healing in rats fed a boron-deficient diet.

    PubMed

    Gorustovich, Alejandro A; Steimetz, Tammy; Nielsen, Forrest H; Guglielmotti, María B

    2008-04-01

    Bone healing after tooth extraction in rats is a suitable experimental model to study bone formation. Thus, we performed a study to determine the effects of boron (B) deficiency on bone healing by using this model. The first lower right molar of weanling Wistar rats was extracted under anesthesia. The animals were divided into two groups: +B (adequate; 3 mg B/kg diet), and -B (boron-deficient; 0.07 mg/kg diet). The animals in both groups were killed in groups of 10 at 7 and 14 days after surgery. The guidelines of the NIH for the care and use of laboratory animals were observed. The mandibles were resected, fixed, decalcified, and embedded in paraffin. Buccolingually oriented sections were obtained at the level of the mesial alveolus and used for histometric evaluations. Total alveolar volume (TAV) and trabecular bone volume per total volume (BV/TV) in the apical third of the alveolus were determined. Percentages of osteoblast surface (ObS), eroded surface (ES), and quiescent surface (QS) were determined. No statistical significant differences in food intake and body weight were observed. Histomorphometric evaluation found -B rats had 36% and 63% reductions in BV/TV at 7 and 14 days, respectively. When compared with +B rats, -B rats had significant reductions (57% and 87%) in ObS concomitantly with increases (120% and 126%) in QS at 7 and 14 days, respectively. The findings show that boron deficiency results in altered bone healing because of a marked reduction in osteogenesis. PMID:18361451

  16. On Adequate Comparisons of Antenna Phase Center Variations

    NASA Astrophysics Data System (ADS)

    Schoen, S.; Kersten, T.

    2013-12-01

    One important part for ensuring the high quality of the International GNSS Service's (IGS) products is the collection and publication of receiver - and satellite antenna phase center variations (PCV). The PCV are crucial for global and regional networks, since they introduce a global scale factor of up to 16ppb or changes in the height component with an amount of up to 10cm, respectively. Furthermore, antenna phase center variations are also important for precise orbit determination, navigation and positioning of mobile platforms, like e.g. the GOCE and GRACE gravity missions, or for the accurate Precise Point Positioning (PPP) processing. Using the EUREF Permanent Network (EPN), Baire et al. (2012) showed that individual PCV values have a significant impact on the geodetic positioning. The statements are further supported by studies of Steigenberger et al. (2013) where the impact of PCV for local-ties are analysed. Currently, there are five calibration institutions including the Institut für Erdmessung (IfE) contributing to the IGS PCV file. Different approaches like field calibrations and anechoic chamber measurements are in use. Additionally, the computation and parameterization of the PCV are completely different within the methods. Therefore, every new approach has to pass a benchmark test in order to ensure that variations of PCV values of an identical antenna obtained from different methods are as consistent as possible. Since the number of approaches to obtain these PCV values rises with the number of calibration institutions, there is the necessity for an adequate comparison concept, taking into account not only the numerical values but also stochastic information and computational issues of the determined PCVs. This is of special importance, since the majority of calibrated receiver antennas published by the IGS origin from absolute field calibrations based on the Hannover Concept, Wübbena et al. (2000). In this contribution, a concept for the adequate

  17. Surgical Guides (Patient-Specific Instruments) for Pediatric Tibial Bone Sarcoma Resection and Allograft Reconstruction

    PubMed Central

    Bellanova, Laura; Paul, Laurent; Docquier, Pierre-Louis

    2013-01-01

    To achieve local control of malignant pediatric bone tumors and to provide satisfactory oncological results, adequate resection margins are mandatory. The local recurrence rate is directly related to inappropriate excision margins. The present study describes a method for decreasing the resection margin width and ensuring that the margins are adequate. This method was developed in the tibia, which is a common site for the most frequent primary bone sarcomas in children. Magnetic resonance imaging (MRI) and computerized tomography (CT) were used for preoperative planning to define the cutting planes for the tumors: each tumor was segmented on MRI, and the volume of the tumor was coregistered with CT. After preoperative planning, a surgical guide (patient-specific instrument) that was fitted to a unique position on the tibia was manufactured by rapid prototyping. A second instrument was manufactured to adjust the bone allograft to fit the resection gap accurately. Pathologic evaluation of the resected specimens showed tumor-free resection margins in all four cases. The technologies described in this paper may improve the surgical accuracy and patient safety in surgical oncology. In addition, these techniques may decrease operating time and allow for reconstruction with a well-matched allograft to obtain stable osteosynthesis. PMID:23533326

  18. Improving access to adequate pain management in Taiwan.

    PubMed

    Scholten, Willem

    2015-06-01

    There is a global crisis in access to pain management in the world. WHO estimates that 4.65 billion people live in countries where medical opioid consumption is near to zero. For 2010, WHO considered a per capita consumption of 216.7 mg morphine equivalents adequate, while Taiwan had a per capita consumption of 0.05 mg morphine equivalents in 2007. In Asia, the use of opioids is sensitive because of the Opium Wars in the 19th century and for this reason, the focus of controlled substances policies has been on the prevention of diversion and dependence. However, an optimal public health outcome requires that also the beneficial aspects of these substances are acknowledged. Therefore, WHO recommends a policy based on the Principle of Balance: ensuring access for medical and scientific purposes while preventing diversion, harmful use and dependence. Furthermore, international law requires that countries ensure access to opioid analgesics for medical and scientific purposes. There is evidence that opioid analgesics for chronic pain are not associated with a major risk for developing dependence. Barriers for access can be classified in the categories of overly restrictive laws and regulations; insufficient medical training on pain management and problems related to assessment of medical needs; attitudes like an excessive fear for dependence or diversion; and economic and logistical problems. The GOPI project found many examples of such barriers in Asia. Access to opioid medicines in Taiwan can be improved by analysing the national situation and drafting a plan. The WHO policy guidelines Ensuring Balance in National Policies on Controlled Substances can be helpful for achieving this purpose, as well as international guidelines for pain treatment. PMID:26068436

  19. Drilling of bone: A comprehensive review

    PubMed Central

    Pandey, Rupesh Kumar; Panda, S.S.

    2013-01-01

    Background Bone fracture treatment usually involves restoring of the fractured parts to their initial position and immobilizing them until the healing takes place. Drilling of bone is common to produce hole for screw insertion to fix the fractured parts for immobilization. Orthopaedic drilling during surgical process causes increase in the bone temperature and forces which can cause osteonecrosis reducing the stability and strength of the fixation. Methods A comprehensive review of all the relevant investigations carried on bone drilling is conducted. The experimental method used, results obtained and the conclusions made by the various researchers are described and compared. Result Review suggests that the further improvement in the area of bone drilling is possible. The systematic review identified several consequential factors (drilling parameters and drill specifications) affecting bone drilling on which there no general agreement among investigators or are not adequately evaluated. These factors are highlighted and use of more advanced methods of drilling is accentuated. The use of more precise experimental set up which resembles the actual situation and the development of automated bone drilling system to minimize human error is addressed. Conclusion In this review, an attempt has been made to systematically organize the research investigations conducted on bone drilling. Methods of treatment of bone fracture, studies on the determination of the threshold for thermal osteonecrosis, studies on the parameters influencing bone drilling and methods of the temperature measurement used are reviewed and the future work for the further improvement of bone drilling process is highlighted. PMID:26403771

  20. Talking Bones.

    ERIC Educational Resources Information Center

    Johnson, Jaclyn; Kassing, Sharon

    2002-01-01

    Describes cooperation with the Saint Louis Zoo to provide opportunities for elementary school students to learn about bones, how animals move, what they eat, and how much they grow. Uses biofacts which include bones, skulls, and other parts to make the laboratory a hands-on experience for students. (YDS)

  1. Bone Infections

    MedlinePlus

    ... include those with diabetes, poor circulation, or recent injury to the bone. You may also be at risk if you are having hemodialysis. Symptoms of bone infections include Pain in the infected area Chills and fever Swelling, warmth, and redness A blood ...

  2. Bone Balance within a Cortical BMU: Local Controls of Bone Resorption and Formation

    PubMed Central

    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. Anatomically safe and minimally invasive transcrestal technique for procurement of autogenous cancellous bone graft from the mid-iliac crest

    PubMed Central

    Missiuna, Paul C.; Gandhi, Harjeet S.; Farrokhyar, Forough; Harnett, Barry E.; Dore, Edward M.G.; Roberts, Barbara

    2011-01-01

    Background Open iliac bone harvesting techniques can result in significant complications and residual morbidity. In reconstructive procedures where a small volume of autogenous cancellous bone graft is required, a minimally invasive technique for bone harvesting applied at the mid-iliac crest has been deemed satisfactory. We sought to assess the application of a well-established surgical technique to procure adequate volume of autogenous cancellous iliac bone graft with minimal trauma to adjacent structures. Methods We retrospectively reviewed the cases of patients who underwent a minimally invasive transcrestal mid-iliac bone graft procurement technique between May 2003 and December 2007. The technique was performed using a 3.5-mm Steinmann pin as a trocar and a 4.5-mm AO drill sleeve as a trephine. We administered a questionnaire, either in the clinic or by mail, to assess a number of parameters, including postoperative pain, dysthesia, parasthesia, status of the donor site wound and patient satisfaction. Results Of the 37 consecutive patients who underwent the procedure, data from 26 patients were available for assessment. Donor site pain resolved within a few days of the surgery, and none of the patients experienced symptoms of chronic pain. At the final review, none of the patients reported any unpleasant signs and symptoms related to the residual scar. Conclusion We recommend that the described minimally invasive trephine method be used when a small cancellous bone graft is needed. We found that patient morbidity was significantly lower with the trephine harvest technique than with open bone harvesting methods at the anterior iliac crest. PMID:21933526

  4. Adequate Vitamin D3 Supplementation During Pregnancy: Decreasing the Prevalence of Asthma and Food Allergies

    PubMed Central

    Finkel, Jonathan; Cira, Courtney; Mazzella, Leanne; Bartyzel, Jim; Ramanna, Annisce; Strimel, Kayla; Waturuocha, Amara; Musser, Nathan; Burress, James; Brammer, Sarah; Wetzel, Robert; Horzempa, Joseph

    2016-01-01

    Vitamin D is a secosterol that is naturally synthesized in the skin upon contact with ultraviolet rays. This vitamin can also be acquired from dietary and nutritional supplements. The active form, vitamin D3, is primarily responsible for calcium homeostasis and bone health. However, many recent studies have associated low levels of vitamin D3 with asthma and food allergies. In this review, we discuss literature to explore the potential that vitamin D3 deficiency may be contributing toward the development of asthma and food allergies. These studies indicate that mothers who supplement with doses of vitamin D3 recommended for daily consumption (400 IU) by the United States Food and Drug Administration is not enough to deliver adequate levels to breastfed infants. Because sufficient vitamin D3 serum levels correlate with a low incidence of asthma and food allergies, high dose vitamin D3 supplementation (4000 IU) by pregnant and breastfeeding women may limit the development of asthma and food allergies in newborns. PMID:27213185

  5. Paget's Disease of Bone

    MedlinePlus

    ... page please turn Javascript on. Paget's Disease of Bone What is Paget's Disease of Bone? Click for more information Enlarged and Misshapen Bones Paget's disease of bone causes affected bones to ...

  6. Metastatic Bone Disease

    MedlinePlus

    ... Bone Disease cont. Page ( 4 ) MBD vs. Primary Bone Cancer The diagnosis of metastatic bone disease should not ... from an unknown primary carcinoma or a primary bone cancer (sarcoma). For example, if an area of bone ...

  7. Bone x-ray

    MedlinePlus

    ... 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 ...

  8. Volume-Based F-18 FDG PET/CT Imaging Markers Provide Supplemental Prognostic Information to Histologic Grading in Patients With High-Grade Bone or Soft Tissue Sarcoma

    PubMed Central

    Andersen, Kim Francis; Fuglo, Hanna Maria; Rasmussen, Sine Hvid; Petersen, Michael Mork; Loft, Annika

    2015-01-01

    Abstract The aim of the study is to assess the prognostic value of different volume-based calculations of tumor metabolic activity in the initial assessment of patients with high-grade bone sarcomas (BS) and soft tissue sarcomas (STS) using F-18 FDG PET/CT. A single-site, retrospective study from 2002 to 2012 including 92 patients with histologically verified high-grade BS (N = 37) or STS (N = 55). All patients underwent a pretreatment F-18 FDG PET/CT scan. Clinical data were registered. Measurements of the accuracy of metabolic tumor volume with a preset threshold of 40% of the maximum standardized uptake value of primary tumor (MTV40%) and total lesion glycolysis (TLG) as prognostic variables and identification of optimal discriminating cut-off values were performed through ROC curve analysis. Patients were grouped according to the cut-off values. All deaths were considered an event in survival analysis. Kaplan–Meier survival estimates and log-rank test were used to compare the degree of equality of survival distributions. Prognostic variables with related hazard ratios (HR) were assessed using Cox proportional hazards regression analysis. Forty-one of 92 patients died during follow-up (45%; 12 BS and 29 STS). Average survival for included patients was 6.5 years (95% CI 5.8–7.3 years) and probability of 5-year survival was 52%. There was a high-significant accuracy of TLG and MTV40% as prognostic variables when looking on all patients and during subgroup analysis. AUCs were higher for TLG than for MTV40%. TLG above optimal cut-off value was the only variable which was independently prognostic for survival throughout multivariate regression analysis of all included patients (P = 0.01, HR 4.78 [95% CI 1.45–15.87]) and subgroup analysis (BS: P = 0.04, HR 11.11 [95% CI 1.09–111.11]; STS: P < 0.05, HR 3.37 [95% CI 1.02–11.11]). No significant results were demonstrated for MTV40%. Volume-based F-18 FDG PET/CT imaging markers in terms of

  9. Volume-Based F-18 FDG PET/CT Imaging Markers Provide Supplemental Prognostic Information to Histologic Grading in Patients With High-Grade Bone or Soft Tissue Sarcoma.

    PubMed

    Andersen, Kim Francis; Fuglo, Hanna Maria; Rasmussen, Sine Hvid; Petersen, Michael Mork; Loft, Annika

    2015-12-01

    The aim of the study is to assess the prognostic value of different volume-based calculations of tumor metabolic activity in the initial assessment of patients with high-grade bone sarcomas (BS) and soft tissue sarcomas (STS) using F-18 FDG PET/CT.A single-site, retrospective study from 2002 to 2012 including 92 patients with histologically verified high-grade BS (N = 37) or STS (N = 55). All patients underwent a pretreatment F-18 FDG PET/CT scan. Clinical data were registered. Measurements of the accuracy of metabolic tumor volume with a preset threshold of 40% of the maximum standardized uptake value of primary tumor (MTV40%) and total lesion glycolysis (TLG) as prognostic variables and identification of optimal discriminating cut-off values were performed through ROC curve analysis. Patients were grouped according to the cut-off values. All deaths were considered an event in survival analysis. Kaplan-Meier survival estimates and log-rank test were used to compare the degree of equality of survival distributions. Prognostic variables with related hazard ratios (HR) were assessed using Cox proportional hazards regression analysis.Forty-one of 92 patients died during follow-up (45%; 12 BS and 29 STS). Average survival for included patients was 6.5 years (95% CI 5.8-7.3 years) and probability of 5-year survival was 52%. There was a high-significant accuracy of TLG and MTV40% as prognostic variables when looking on all patients and during subgroup analysis. AUCs were higher for TLG than for MTV40%. TLG above optimal cut-off value was the only variable which was independently prognostic for survival throughout multivariate regression analysis of all included patients (P = 0.01, HR 4.78 [95% CI 1.45-15.87]) and subgroup analysis (BS: P = 0.04, HR 11.11 [95% CI 1.09-111.11]; STS: P < 0.05, HR 3.37 [95% CI 1.02-11.11]). No significant results were demonstrated for MTV40%.Volume-based F-18 FDG PET/CT imaging markers in terms of pretreatment estimation

  10. [Rhythmic nuclear growth of adequately stimulated ganglia cells of acoustic nuclei (rat)].

    PubMed

    Köpf-Maier, P; Wüstenfeld, E

    1975-01-01

    Ganglia cells of the dorsal and ventral cochlear nuclei of white rats were irritated adequately for different periods or left untreated, respectively, and investigated karyometrically. The frequency distribution curves of the nuclear volumes were separated by means of an electronic curve resolver into the component curves, i.e. into groups of nuclei obeying exactly a Gaussian normal distribution and thus representing biologically uniform populations. The analysis of the mean values of the component curves led to the following results: 1. The mean values of the component curves can be arranged in 2 series having the pattern V1, V1 square root 2, V2, V2 square root 2, V4, V4 square root 2...2. The series V1, V1 square root 2, V2, V2 square root 2...is based on a geometrical series of the general formula an = k-qn. 3. It follows from these results that the nuclear volumes grow rhythmically by a factor of square root 2 and, consequently, that there is a periodical doubling in in the growth of the surface. PMID:1200386

  11. Cosmos 1129 - Spaceflight and bone changes

    NASA Technical Reports Server (NTRS)

    Wronski, T. J.; Morey-Holton, E.; Jee, W. S. S.

    1980-01-01

    Male Wistar rats were placed in orbit for an 18.5 day period aboard the Soviet Cosmos 1129 biological satellite. The skeletal changes which occurred during spaceflight were determined to be a reduced rate of periosteal bone formation in the tibial and humeral diaphyses, and a decreased trabecular bone volume and an increased fat content of the bone marrow in the proximal tibial metaphysis.

  12. A quantification strategy for missing bone mass in case of osteolytic bone lesions

    SciTech Connect

    Fränzle, Andrea Giske, Kristina; Bretschi, Maren; Bäuerle, Tobias; Hillengass, Jens; Bendl, Rolf

    2013-12-15

    Purpose: Most of the patients who died of breast cancer have developed bone metastases. To understand the pathogenesis of bone metastases and to analyze treatment response of different bone remodeling therapies, preclinical animal models are examined. In breast cancer, bone metastases are often bone destructive. To assess treatment response of bone remodeling therapies, the volumes of these lesions have to be determined during the therapy process. The manual delineation of missing structures, especially if large parts are missing, is very time-consuming and not reproducible. Reproducibility is highly important to have comparable results during the therapy process. Therefore, a computerized approach is needed. Also for the preclinical research, a reproducible measurement of the lesions is essential. Here, the authors present an automated segmentation method for the measurement of missing bone mass in a preclinical rat model with bone metastases in the hind leg bones based on 3D CT scans. Methods: The affected bone structure is compared to a healthy model. Since in this preclinical rat trial the metastasis only occurs on the right hind legs, which is assured by using vessel clips, the authors use the left body side as a healthy model. The left femur is segmented with a statistical shape model which is initialised using the automatically segmented medullary cavity. The left tibia and fibula are segmented using volume growing starting at the tibia medullary cavity and stopping at the femur boundary. Masked images of both segmentations are mirrored along the median plane and transferred manually to the position of the affected bone by rigid registration. Affected bone and healthy model are compared based on their gray values. If the gray value of a voxel indicates bone mass in the healthy model and no bone in the affected bone, this voxel is considered to be osteolytic. Results: The lesion segmentations complete the missing bone structures in a reasonable way. The mean

  13. [Long Bone Nonunion].

    PubMed

    Schmidmaier, G; Moghaddam, A

    2015-12-01

    The percentage of delayed or non-unions after fractures of long bones depends on the individual risk profile at approximately 10 %. The current definition states that a non-union is a fracture that will not consolidate without any further intervention - independent from the treatment time. At the early stage of a non-union a conservative treatment is possible in case of an adequately stable situation. The operative treatment depends on the type of the non-union. There are one-step or two-step procedures, all according to the principles of the "diamond concept". This means improvement of the mechanical situation - in most cases by means of a reosteosynthesis - and vascularization, local application of osteoconductive carriers e.g. tricalciumphosphate, vital cells from autologous bone and osteoinductive substances like bone morphogenetic proteins (BMP-2 or BMP-7). Hypertrophic and atrophic non-unions without large defect gaps or signs of infection can be treated with a one-step procedure. For treating infected non-unions or non-unions with large defect gaps the Masquelet technique is recommended. PMID:26670151

  14. Quantitative computed tomography of bone.

    PubMed

    Rüegsegger, P; Stebler, B; Dambacher, M

    1982-07-01

    Computed tomography (CT) is well accepted as an imaging procedure, but comparatively little effort has been made to utilize the potential capability of CT to quantify tissue densities and composition. There are two reasons for this. First, precision and accuracy of quantification are limited by nonlinear effects. These effects are nonlocal and are object and scanner dependent. Second, intraindividual and interindividual variations of tissue compositions are considerable. Single energy measurements require restrictive assumptions on tissue compositions. The diagnosis and treatment monitoring of osteopenic bone diseases with low-dose CT is given as an example of a successful application of quantitative CT. With a special-purpose CT system and an analytic procedure for the quantification of bone at peripheral measuring sites, longitudinal examinations were performed. Low-dose quantitative CT permitted quantification, on an individual basis, of the bone loss of immobilization osteoporosis on a week-by-week basis. Changes due to postmenopausal osteoporosis are less drastic, and so measurement at intervals of months is adequate. In women after menopause, 3-month intervals were used in evaluating the natural course of osteoporosis and in quantifying the effects of sodium fluoride treatment on trabecular bone. Low-dose quantitative CT has proved to be a sensitive and highly reproducible procedure for the noninvasive evaluation of bone loss or bone accretion. During a disease or therapy, each patient can be evaluated individually. PMID:7121079

  15. LORENZ: a system for planning long-bone fracture reduction

    NASA Astrophysics Data System (ADS)

    Birkfellner, Wolfgang; Burgstaller, Wolfgang; Wirth, Joachim; Baumann, Bernard; Jacob, Augustinus L.; Bieri, Kurt; Traud, Stefan; Strub, Michael; Regazzoni, Pietro; Messmer, Peter

    2003-05-01

    Long bone fractures belong to the most common injuries encountered in clinical routine trauma surgery. Preoperative assessment and decision making is usually based on standard 2D radiographs of the injured limb. Taking into account that a 3D - imaging modality such as computed tomography (CT) is not used for diagnosis in clinical routine, we have designed LORENZ, a fracture reduction planning tool based on such standard radiographs. Taking into account the considerable success of so-called image free navigation systems for total knee replacement in orthopaedic surgery, we assume that a similar tool for long bone fracture reposition should have considerable impact on computer-aided trauma surgery in a standard clinical routine setup. The case for long bone fracture reduction is, however, somewhat more complicated since not only scale independent angles indicating biomechanical measures such as varus and valgus are involved. Reduction path planning requires that the individual anatomy and the classification of the fracture is taken into account. In this paper, we present the basic ideas of this planning tool, it's current state, and the methodology chosen. LORENZ takes one or more conventional radiographs of the broken limb as input data. In addition, one or more x-rays of the opposite healthy bone are taken and mirrored if necessary. A most adequate CT model is being selected from a database; currently, this is achieved by using a scale space approach on the digitized x-ray images and comparing standard perspective renderings to these x-rays. After finding a CT-volume with a similar bone, a triangulated surface model is generated, and the surgeon can break the bone and arrange the fragments in 3D according to the x-ray images of the broken bone. Common osteosynthesis plates and implants can be loaded from CAD-datasets and are visualized as well. In addition, LORENZ renders virtual x-ray views of the fracture reduction process. The hybrid surface/voxel rendering

  16. Fundamental ratios and logarithmic periodicity in human limb bones

    PubMed Central

    Pietak, Alexis; Ma, Siyan; Beck, Caroline W; Stringer, Mark D

    2013-01-01

    Fundamental mathematical relationships are widespread in biology yet there is little information on this topic with regard to human limb bone lengths and none related to human limb bone volumes. Forty-six sets of ipsilateral upper and lower limb long bones and third digit short bones were imaged by computed tomography. Maximum bone lengths were measured manually and individual bone volumes calculated from computed tomography images using a stereologic method. Length ratios of femur : tibia and humerus : ulna were remarkably similar (1.21 and 1.22, respectively) and varied little (<7%) between individuals. The volume ratio of femur : tibia was approximately half that of humerus : ulna (1.58 and 3.28, respectively; P < 0.0001). Lower limb bone volume ratios varied much more than upper limb ratios. The relationship between bone length and volume was found to be well described by power laws, with R2 values ranging from 0.983 to 0.995. The most striking finding was a logarithmic periodicity in bone length moving from distal to proximal up the limb (upper limb λ = 0.72, lower limb λ = 0.93). These novel data suggest that human limb bone lengths and volumes follow fundamental and highly conserved mathematical relationships, which may contribute to our understanding of normal and disordered growth, stature estimation, and biomechanics. PMID:23521756

  17. Prediction of mechanical properties of trabecular bone using quantitative MRI

    NASA Astrophysics Data System (ADS)

    Lammentausta, E.; Hakulinen, M. A.; Jurvelin, J. S.; Nieminen, M. T.

    2006-12-01

    Techniques for quantitative magnetic resonance imaging (MRI) have been developed for non-invasive estimation of the mineral density and structure of trabecular bone. The R*2 relaxation rate (i.e. 1/T*2) is sensitive to bone mineral density (BMD) via susceptibility differences between trabeculae and bone marrow, and by binarizing MRI images, structural variables, such as apparent bone volume fraction, can be assessed. In the present study, trabecular bone samples of human patellae were investigated in vitro at 1.5 T to determine the ability of MRI-derived variables (R*2 and bone volume fraction) to predict the mechanical properties (Young's modulus, yield stress and ultimate strength). Further, the MRI variables were correlated with reference measurements of volumetric BMD and bone area fraction as determined with a clinical pQCT system. The MRI variables correlated significantly (p < 0.01) with the mechanical variables (r = 0.32-0.46), BMD (r = 0.56) and bone structure (r = 0.51). A combination of R*2 and MRI-derived bone volume fraction further improved the prediction of yield stress and ultimate strength. Although pQCT showed a trend towards better prediction of the mechanical properties, current results demonstrate the feasibility of combined MR imaging of marrow susceptibility and bone volume fraction in predicting the mechanical strength of trabecular bone and bone mineral density.

  18. Strontium doping of bone graft extender

    PubMed Central

    2011-01-01

    Background and purpose Allografts are often used during revision hip replacement surgery for stabilization of the implant. Resorption of the allograft may exceed new bone formation, and instability of the prosthesis can develop. We investigated whether strontium could regulate the imbalance of fast resorption of allograft and slower formation of new bone, because it is both an anabolic and an anticatabolic agent. Method Strontium was added to the implant interface environment by doping a hydroxyapatite bone graft extender. 10 dogs each received 2 experimental titanium implants. The implants were inserted within a 2.7-mm concentric gap in cancellous bone. The gap was filled with 50% (v/v) allograft mixed with 50% bone graft extender. The extender either had 5% strontium doping (SrHA) or was undoped (HA). After 4 weeks, osseointegration and mechanical fixation were evaluated by histomorphometry and by push-out test. Results SrHA bone graft extender induced a 1.2-fold increase in volume of new bone, a 1.2-fold increase in allograft remaining in the gap, and a 1.4-fold increase in surface area of the bone graft extender material in contact with new bone compared to HA bone graft extender. All these increases were statistically significant. SrHA bone graft extender did not significantly improve ongrowth of bone onto the implants or improve any of the mechanical push-out parameters compared to HA bone graft extender. Interpretation Doping of the HA bone graft extender with 5% strontium increased gap healing, preserved more of the allograft in the gap, and increased the ongrowth of bone onto the bone graft extender material, but did not improve mechanical fixation. PMID:21895497

  19. Brown adipose tissue and bone

    PubMed Central

    Lidell, M E; Enerbäck, S

    2015-01-01

    Brown adipose tissue (BAT) is capable of transforming chemically stored energy, in the form of triglycerides, into heat. Recent studies have shown that metabolically active BAT is present in a large proportion of adult humans, where its activity correlates with a favorable metabolic status. Hence, the tissue is now regarded as an interesting target for therapies against obesity and associated diseases such as type 2 diabetes, the hypothesis being that an induction of BAT would be beneficial for these disease states. Apart from the association between BAT activity and a healthier metabolic status, later studies have also shown a positive correlation between BAT volume and both bone cross-sectional area and bone mineral density, suggesting that BAT might stimulate bone anabolism. The aim of this review is to give the reader a brief overview of the BAT research field and to summarize and discuss recent findings regarding BAT being a potential player in bone metabolism. PMID:27152171

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

    PubMed

    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

  1. Bone marrow transplant

    MedlinePlus

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

  2. Bone marrow transplant

    MedlinePlus

    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 ...

  3. Percentage of Adults with High Blood Pressure Whose Hypertension Is Adequately Controlled

    MedlinePlus

    ... is Adequately Controlled Percentage of Adults with High Blood Pressure Whose Hypertension is Adequately Controlled Heart disease ... Survey. Age Group Percentage of People with High Blood Pressure that is Controlled by Age Group f94q- ...

  4. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... production performance, or biased observation. One or more adequate and well-controlled studies are required... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Adequate and well-controlled studies. 514.117... Applications § 514.117 Adequate and well-controlled studies. (a) Purpose. The primary purpose of...

  5. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... production performance, or biased observation. One or more adequate and well-controlled studies are required... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Adequate and well-controlled studies. 514.117... Applications § 514.117 Adequate and well-controlled studies. (a) Purpose. The primary purpose of...

  6. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... production performance, or biased observation. One or more adequate and well-controlled studies are required... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Adequate and well-controlled studies. 514.117... Applications § 514.117 Adequate and well-controlled studies. (a) Purpose. The primary purpose of...

  7. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... production performance, or biased observation. One or more adequate and well-controlled studies are required... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Adequate and well-controlled studies. 514.117... Applications § 514.117 Adequate and well-controlled studies. (a) Purpose. The primary purpose of...

  8. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... production performance, or biased observation. One or more adequate and well-controlled studies are required... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Adequate and well-controlled studies. 514.117... Applications § 514.117 Adequate and well-controlled studies. (a) Purpose. The primary purpose of...

  9. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  10. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  11. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  12. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  13. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  14. 76 FR 51041 - Hemoglobin Standards and Maintaining Adequate Iron Stores in Blood Donors; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-17

    ... HUMAN SERVICES Food and Drug Administration Hemoglobin Standards and Maintaining Adequate Iron Stores in... Standards and Maintaining Adequate Iron Stores in Blood Donors.'' The purpose of this public workshop is to... donor safety and blood availability, and potential measures to maintain adequate iron stores in...

  15. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve Snowmachine (snowmobile) Operations § 13.960 Who determines when there is adequate snow cover? The superintendent will determine when snow cover is adequate for snowmachine use. The superintendent will follow...

  16. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve Snowmachine (snowmobile) Operations § 13.960 Who determines when there is adequate snow cover? The superintendent will determine when snow cover is adequate for snowmachine use. The superintendent will follow...

  17. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve Snowmachine (snowmobile) Operations § 13.960 Who determines when there is adequate snow cover? The superintendent will determine when snow cover is adequate for snowmachine use. The superintendent will follow...

  18. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve Snowmachine (snowmobile) Operations § 13.960 Who determines when there is adequate snow cover? The superintendent will determine when snow cover is adequate for snowmachine use. The superintendent will follow...

  19. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve Snowmachine (snowmobile) Operations § 13.960 Who determines when there is adequate snow cover? The superintendent will determine when snow cover is adequate for snowmachine use. The superintendent will follow...

  20. Reconstruction of alveolar bone defect with autogenous bone particles and osseointegrated implants: Histologic analysis and 10 years monitoring

    PubMed Central

    de Carvalho, Paulo Sérgio Perri; de Carvalho, Mariliza Comar Astolphi; Ponzoni, Daniela

    2015-01-01

    Maintaining the volume of the alveolar process after extraction can be achieved by immediate implant placement and guided bone regeneration, with or without the use of biomaterials. The authors present a case report with a 10 years follow-up, rehabilitation using osseointegrated implants in the extraction area and maintenance of the volume of the alveolar process with autogenous cortical bone shavings. PMID:26389054

  1. The peak bone mass concept: is it still relevant?

    PubMed

    Schönau, Eckhard

    2004-08-01

    The peak bone mass concept implies that optimal skeletal development during childhood and adolescence will prevent fractures in late adulthood. This concept is based on the observation that areal bone density increases with growth during childhood, is highest around 20 years of age and declines thereafter. However, it is now clear that strong bones in the youngster do not necessarily lead to a fracture-free old age. In the recent bone densitometric literature, the terms bone mass and bone density are typically used synonymously. In physics, density has been defined as the mass of a body divided by its volume. In clinical practice and science, "bone density" usually has a different meaning-the degree to which a radiation beam is attenuated by a bone, as judged from a two-dimensional projection image (areal bone density). The attenuation of a radiation beam does not only depend on physical density, but also on bone size. A small bone therefore has a lower areal bone density than a larger bone, even if the physical density is the same. Consequently, a low areal bone density value can simply reflect the small size of an otherwise normal bone. At present, bone mass analysis is very useful for epidemiological studies on factors that may have an impact on bone development. There is an ongoing discussion about whether the World Health Organization (WHO) definition of osteoporosis is over-simplistic and requires upgrading to include indices representing the distribution of bone and mineral (bone strength indices). The following suggestions and recommendations outline a new concept: bone mass should not be related to age. There is now more and more evidence that bone mass should be related to bone size or muscle function. Thus analyzed, there is no such entity as a "peak bone mass". Many studies are currently under way to evaluate whether these novel approaches increase sensitivity and specificity of fracture prediction in an individual. Furthermore, the focus of many bone

  2. Dietary Pseudopurpurin Improves Bone Geometry Architecture and Metabolism in Red-Bone Guishan Goats

    PubMed Central

    Han, TieSuo; Li, Peng; Wang, JianGuo; Liu, GuoWen; Wang, Zhe; Ge, ChangRong; Gao, ShiZheng

    2012-01-01

    Red-colored bones were found initially in some Guishan goats in the 1980s, and they were designated red-boned goats. However, it is not understood what causes the red color in the bone, or whether the red material changes the bone geometry, architecture, and metabolism of red-boned goats. Pseudopurpurin was identified in the red-colored material of the bone in red-boned goats by high-performance liquid chromatography–electrospray ionization–mass spetrometry and nuclear magnetic resonance analysis. Pseudopurpurin is one of the main constituents of Rubia cordifolia L, which is eaten by the goats. The assessment of the mechanical properties and micro-computed tomography showed that the red-boned goats displayed an increase in the trabecular volume fraction, trabecular thickness, and the number of trabeculae in the distal femur. The mean thickness, inner perimeter, outer perimeter, and area of the femoral diaphysis were also increased. In addition, the trabecular separation and structure model index of the distal femur were decreased, but the bone mineral density of the whole femur and the mechanical properties of the femoral diaphysis were enhanced in the red-boned goats. Meanwhile, expression of alkaline phosphatase and osteocalcin mRNA was higher, and the ratio of the receptor activator of the nuclear factor kappa B ligand to osteoprotegerin was markedly lower in the bone marrow of the red-boned goats compared with common goats. To confirm further the effect of pseudopurpurin on bone geometry, architecture, and metabolism, Wistar rats were fed diets to which pseudopurpurin was added for 5 months. Similar changes were observed in the femurs of the treated rats. The above results demonstrate that pseudopurpurin has a close affinity with the mineral salts of bone, and consequently a high level of mineral salts in the bone cause an improvement in bone strength and an enhancement in the structure and metabolic functions of the bone. PMID:22624037

  3. The effects of surgicel and bone wax hemostatic agents on bone healing: An experimental study

    PubMed Central

    Nooh, Nasser; Abdullah, Walid A; Grawish, Mohammed El-Awady; Ramalingam, Sundar; Javed, Fawad; Al-Hezaimi, Khalid

    2014-01-01

    Background: The biological effects of hemostatic agends on the physiological healing process need to be tested. The aim of this study was to assess the effects of oxidized cellulose (surgicel) and bone wax on bone healing in goats’ feet. Materials and Methods: Three congruent circular bone defects were created on the lateral aspects of the right and left metacarpal bones of ten goats. One defect was left unfilled and acted as a control; the remaining two defects were filled with bone wax and surgicel respectively. The 10 animals were divided into two groups of 5 animals each, to be sacrificed at the 3rd and 5th week postoperatively. Histological analysis assessing quality of bone formed and micro-computed tomography (MCT) measuring the quantities of bone volume (BV) and bone density (BD) were performed. The results of MCT analysis pertaining to BV and BD were statistically analyzed using two-way analysis of variance (ANOVA) and posthoc least significant difference tests. Results: Histological analysis at 3 weeks showed granulation tissue with new bone formation in the control defects, active bone formation only at the borders for surgicel filled defects and fibrous encapsulation with foreign body reaction in the bone wax filled defects. At 5 weeks, the control and surgicel filled defects showed greater bone formation; however the control defects had the greatest amount of new bone. Bone wax filled defects showed very little bone formation. The two-way ANOVA for MCT results showed significant differences for BV and BD between the different hemostatic agents during the two examination periods. Conclusion: Surgicel has superiority over bone wax in terms of osseous healing. Bone wax significantly hinders osteogenesis and induces inflammation. PMID:24932041

  4. Bone Marrow Diseases

    MedlinePlus

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

  5. Bone Marrow Transplantation

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a person's ...

  6. Genetics of Bone Density

    MedlinePlus

    ... study linked 32 novel genetic regions to bone mineral density. The findings may help researchers understand why ... or treating osteoporosis. Bones are made of a mineral and protein scaffold filled with bone cells. Bone ...

  7. Calcium and bones

    MedlinePlus

    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. ...

  8. Bone biopsy (image)

    MedlinePlus

    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 ...

  9. Bone lesion biopsy

    MedlinePlus

    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 ...

  10. Investigation of effect of variations in bone fraction and red marrow cellularity on bone marrow dosimetry in radio-immunotherapy

    NASA Astrophysics Data System (ADS)

    Wilderman, S. J.; Roberson, P. L.; Bolch, W. E.; Dewaraja, Y. K.

    2013-07-01

    A method is described for computing patient-specific absorbed dose rates to active marrow which accounts for spatial variation in bone volume fraction and marrow cellularity. A module has been added to the 3D Monte Carlo dosimetry program DPM to treat energy deposition in the components of bone spongiosa distinctly. Homogeneous voxels in regions containing bone spongiosa (as defined on CT images) are assumed to be comprised only of bone, active (red) marrow and inactive (yellow) marrow. Cellularities are determined from biopsy, and bone volume fractions are computed from cellularities and CT-derived voxel densities. Electrons are assumed to deposit energy locally in the three constituent components in proportions determined by electron energy absorption fractions which depend on energy, cellularity, and bone volume fraction, and which are either taken from the literature or are derived from Monte Carlo simulations using EGS5. Separate algorithms are used to model primary β particles and secondary electrons generated after photon interactions. Treating energy deposition distinctly in bone spongiosa constituents leads to marrow dosimetry results which differ from homogeneous spongiosa dosimetry by up to 20%. Dose rates in active marrow regions with cellularities of 20, 50, and 80% can vary by up to 20%, and can differ by up to 10% as a function of bone volume fraction. Dose to bone marrow exhibits a strong dependence on marrow cellularity and a potentially significant dependence on bone volume fraction.

  11. Bone Quality in Paget's Disease of Bone.

    PubMed

    Singer, Frederick R

    2016-04-01

    Paget's disease of bone is produced by a localized increase in osteoclastic and osteoblastic activity which can progress slowly to involve an entire bone if untreated. A common feature is enlarged bones which are deformed, particularly in weight-bearing regions of the skeleton such as the lower extremity. Pathologic fractures may be a consequence, and nonunion of femoral fractures is not uncommon. Analyses of bone biopsies from patients with Paget's disease indicate that there is a lower, heterogeneous degree of bone mineralization and a younger tissue age than that found in control bone. Pagetic bone also has less resistance to plastic deformation and a straighter crack path than control bone. PMID:26943142

  12. Diet-induced obesity alters bone remodeling leading to decreased femoral trabecular bone mass in mice.

    PubMed

    Cao, Jay J; Sun, Li; Gao, Hongwei

    2010-03-01

    Obesity-derived body mass may be detrimental to bone health through not well-defined mechanisms. In this study we determined changes in bone structure and serum cytokines related to bone metabolism in diet-induced obese mice. Mice fed a high-fat diet (HFD) had higher serum tartrate-resistant acid phosphatase (TRAP) and leptin but lower osteocalcin concentrations than those fed the normal-fat diet. The HFD increased multinucleated TRAP-positive osteoclasts in bone marrow compared to the control diet. Despite being much heavier, mice fed the HFD had lower femoral bone volume, trabecular number, and connectivity density and higher trabecular separation than mice on the control diet. These findings suggest that obesity induced by a HFD increases bone resorption that may blunt any positive effects of increased body weight on bone. PMID:20392249

  13. BONE BANKS

    PubMed Central

    de Alencar, Paulo Gilberto Cimbalista; Vieira, Inácio Facó Ventura

    2015-01-01

    Bone banks are necessary for providing biological material for a series of orthopedic procedures. The growing need for musculoskeletal tissues for transplantation has been due to the development of new surgical techniques, and this has led to a situation in which a variety of hospital services have been willing to have their own source of tissue for transplantation. To increase the safety of transplanted tissues, standards for bone bank operation have been imposed by the government, which has limited the number of authorized institutions. The good performance in a bone bank depends on strict control over all stages, including: formation of well-trained harvesting teams; donor selection; conducting various tests on the tissues obtained; and strict control over the processing techniques used. Combination of these factors enables greater scope of use and numbers of recipient patients, while the incidence of tissue contamination becomes statistically insignificant, and there is traceability between donors and recipients. This paper describes technical considerations relating to how a bone bank functions, the use of grafts and orthopedic applications, the ethical issues and the main obstacles encountered. PMID:27026958

  14. Broken bone

    MedlinePlus

    ... from a height Motor vehicle accidents Direct blow Child abuse Repetitive forces, such as those caused by running, ... you can clearly see a deformity, assume the child has a broken bone and get medical help. Prevention Take the following steps to reduce your risk ...

  15. Impact of lanthanum carbonate on cortical bone in dialysis patients with adynamic bone disease.

    PubMed

    Yajima, Aiji; Inaba, Masaaki; Tominaga, Yoshihiro; Tanaka, Motoko; Otsubo, Shigeru; Nitta, Kosaku; Ito, Akemi; Satoh, Shigeru

    2013-04-01

    Among the most serious problems in patients with chronic kidney disease (CKD) is fragility of cortical bone caused by cortical thinning and increased cortical porosity; the cortical fragility is sometimes irreversible, with fractures generally initiating from cortical bone. Therefore, development of treatments for problems of cortical bone is urgently desired. Cortical bone has the three surfaces, including the periosteal surface, intracortical spaces and endocortical surface. Bone turnover at the endocortical surface and intracortical resorption spaces are increased as compared with that at cancellous surface. Bone growth sometimes depends on apposition at the periosteal surface. We treated hyperphosphatemia in two hemodialysis patients with adynamic bone disease with 750-1500 mg/day of lanthanum carbonate, which is a non-calcium containing phosphate binder; the treatment resulted in a decrease of the serum phosphorus levels (P levels), without significant change of the serum intact parathyroid hormone levels. We now report that treatment of these patients with lanthanum carbonate increased mineralization of the periosteal surface, increased bone mass within the intracortical resorption spaces and increased mineralization of the minimodeling surface at the endocortical surface. In addition, woven bone volume in cortical bone was decreased and mineralization of bone units, namely, osteons, was increased. Although these findings were not observed across all surfaces of the cortical bone in the patients, it is expected that lanthanum carbonate would increase the cortical stability in CKD patients, with consequent reduction in the fracture rate in these patients. PMID:23586512

  16. The materials used in bone tissue engineering

    SciTech Connect

    Tereshchenko, V. P. Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M.

    2015-11-17

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

  17. The materials used in bone tissue engineering

    NASA Astrophysics Data System (ADS)

    Tereshchenko, V. P.; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M.

    2015-11-01

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

  18. Bone densitometry in infants

    SciTech Connect

    Barden, H.S.; Mazess, R.B.

    1988-07-01

    Bone mineral mass and density can be measured noninvasively by various absorptiometric procedures. Two methods, dual-photon absorptiometry (DPA) and quantitative computed tomography, have widespread application in adults but only limited use in children. One method, single-photon absorptiometry (SPA), has been used extensively in adults and children and has been modified for use in infants. The radius shaft has been used for most research on infants. However, the difficulty of using older SPA methods on this small bone (4 to 7 mm width) has led a few investigators to measure the shaft of the humerus. The typical precision of measurement in a newborn is about 5% with the use of computerized rectilinear scanners for the radius; older linear scanners have a precision error of 5% to 10% on the humerus. Linear scanners cannot measure precisely the radius in individual neonates. The SPA scans typically take about 5 minutes. The DPA technique using /sup 153/Gd has been modified for use on smaller animals (5 to 10 kg monkeys and dogs), but it has not been used on infants because DPA scans take 20 minutes. New methods using x-ray absorptiometry allow rapid (1 minute), precise (1%) measurements in the perinate. The need for a soft tissue bolus is eliminated, and both the axial and peripheral skeletons can be measured with dual-energy x-ray absorptiometry. Ultrasonic measurements do not yet offer adequate precision in the neonate, given the limited biologic range of values. 83 references.

  19. Physiological bases of bone regeneration II. The remodeling process.

    PubMed

    Fernández-Tresguerres-Hernández-Gil, Isabel; Alobera-Gracia, Miguel Angel; del-Canto-Pingarrón, Mariano; Blanco-Jerez, Luis

    2006-03-01

    Bone remodeling is the restructuring process of existing bone, which is in constant resorption and formation. Under normal conditions, this balanced process allows the renewal of 5-10% of bone volume per year. At the microscopic level, bone remodeling is produced in basic multicellular units, where osteoclasts resorb a certain quantity of bone and osteoblasts form the osteoid matrix and mineralize it to fill the previously created cavity. These units contain osteoclasts, macrophages, preosteoblasts and osteoblasts, and are controlled by a series of factors, both general and local, allowing normal bone function and maintaining the bone mass. When this process becomes unbalanced then bone pathology appears, either in excess (osteopetrosis) or deficit (osteoporosis). The purpose of this study is to undertake a revision of current knowledge on the physiological and biological mechanisms of the bone remodeling process; highlighting the role played by the regulating factors, in particular that of the growth factors. PMID:16505794

  20. Characterizing light propagation in bone for photodynamic therapy of osteosarcoma

    NASA Astrophysics Data System (ADS)

    Rossi, Vincent M.; Gustafson, Scott B.; Jacques, Steven L.

    2009-02-01

    This work aims at characterizing how light propagates through bone in order to efficiently guide treatment of osteosarcoma with photodynamic therapy (PDT). Optical properties of various bone tissues need to be characterized in order to have a working model of light propagation in bone. Bone tissues of particular interest include cortical bone, red and yellow marrow, cancellous bone, and bone cancers themselves. With adequate knowledge of optical properties of osseous tissues, light dosimetry can determine how best to deliver adequate light to achieve phototoxic effects within bone. An optical fiber source-collector pair is used for diffuse reflectance spectroscopic measurements in order to determine the scattering and absorption properties of bone tissues. Native absorbers of interest at visible and near-IR wavelengths include water and oxygenated and deoxygenated hemoglobin. A cylindrically symmetric Monte Carlo model is then used, incorporating these results, in order to predict and guide the delivery of light within bone in order to achieve the desired phototoxic effect in PDT.

  1. Graded Porous β-Tricalcium Phosphate Scaffolds Enhance Bone Regeneration in Mandible Augmentation

    PubMed Central

    Yang, Jingwen; Kang, Yunqing; Browne, Christopher; Jiang, Ting; Yang, Yunzhi

    2015-01-01

    Abstract Bone augmentation requires scaffold to promote forming of natural bone structure. Currently, most of the reported bone scaffolds are porous solids with uniform pores. The aim of the currentstudy is to evaluate the effect of a graded porous β-tricalcium phosphate scaffolds on alveolar bone augmentation. Three groups of scaffolds were fabricated by a template-casting method: (1) graded porous scaffolds with large pores in the center and small pores at theperiphery, (2) scaffolds with large uniform pores, and (3) scaffolds with small uniform pores. Bone augmentation on rabbit mandible wasinvestigated by microcomputed tomography, sequential fluorescentlabeling, and histologic examination 3 months after implantation.The result presents that all the scaffold groups maintain their augmented bone height after 3-month observation, whereas the autograftinggroup presents an obvious bone resorption. Microcomputed tomography reveals that the graded porous group has significantly greater volume of new bone (P < 0.05) and similar bone density compared with the uniform pores groups. Bone substance distributes unevenly in all the 3 experimental groups. Greater bone volume can be observed in the area closer to the bone bed. The sequential fluorescentlabeling observation reveals robust bone regeneration in the first month and faster bone growth in the graded porous scaffold group than that in the large porous scaffold group. Histologic examinationsconfirm bone structure in the aspect of distribution, activity, and maturity. We conclude that graded porous designed biodegradableβ-tricalcium phosphate scaffolds are beneficial to promote bone augmentation in the aspect of bone volume. PMID:25675019

  2. [Bone metabolism and fracture risk in anorexia nervosa].

    PubMed

    Fernández Soto, María Luisa; González Jiménez, Amalia; Varsavsky, Mariela

    2010-07-17

    The prevalence of anorexia nervosa has increased in recent years and a large proportion of patients with this disorder have low bone density at diagnosis and, therefore, an increased risk of early and late fractures. The mechanism of bone loss in anorexia nervosa is not well understood, yet it likely includes hypogonadism, alterations of the GH-IGF-1 axis and hypercortisolism. DEXA is the most effective tool for assessing and monitoring bone density in these patients, and it is important to improve or at least stabilize bone metabolism in those with low bone mass. No agent has yet been proven to be effective in improving bone density. However, sustained weight recovery and menses besides an adequate intake of calcium and vitamin D are recommended to optimize the conditions in which bone mass accrual may occur. PMID:19631350

  3. Suppressed bone remodeling in black bears conserves energy and bone mass during hibernation

    PubMed Central

    McGee-Lawrence, Meghan; Buckendahl, Patricia; Carpenter, Caren; Henriksen, Kim; Vaughan, Michael; Donahue, Seth

    2015-01-01

    ABSTRACT Decreased physical activity in mammals increases bone turnover and uncouples bone formation from bone resorption, leading to hypercalcemia, hypercalcuria, bone loss and increased fracture risk. Black bears, however, are physically inactive for up to 6 months annually during hibernation without losing cortical or trabecular bone mass. Bears have been shown to preserve trabecular bone volume and architectural parameters and cortical bone strength, porosity and geometrical properties during hibernation. The mechanisms that prevent disuse osteoporosis in bears are unclear as previous studies using histological and serum markers of bone remodeling show conflicting results. However, previous studies used serum markers of bone remodeling that are known to accumulate with decreased renal function, which bears have during hibernation. Therefore, we measured serum bone remodeling markers (BSALP and TRACP) that do not accumulate with decreased renal function, in addition to the concentrations of serum calcium and hormones involved in regulating bone remodeling in hibernating and active bears. Bone resorption and formation markers were decreased during hibernation compared with when bears were physically active, and these findings were supported by histomorphometric analyses of bone biopsies. The serum concentration of cocaine and amphetamine regulated transcript (CART), a hormone known to reduce bone resorption, was 15-fold higher during hibernation. Serum calcium concentration was unchanged between hibernation and non-hibernation seasons. Suppressed and balanced bone resorption and formation in hibernating bears contributes to energy conservation, eucalcemia and the preservation of bone mass and strength, allowing bears to survive prolonged periods of extreme environmental conditions, nutritional deprivation and anuria. PMID:26157160

  4. Engineering anatomically shaped human bone grafts

    PubMed Central

    Grayson, Warren L.; Fröhlich, Mirjam; Yeager, Keith; Bhumiratana, Sarindr; Chan, M. Ete; Cannizzaro, Christopher; Wan, Leo Q.; Liu, X. Sherry; Guo, X. Edward; Vunjak-Novakovic, Gordana

    2009-01-01

    The ability to engineer anatomically correct pieces of viable and functional human bone would have tremendous potential for bone reconstructions after congenital defects, cancer resections, and trauma. We report that clinically sized, anatomically shaped, viable human bone grafts can be engineered by using human mesenchymal stem cells (hMSCs) and a “biomimetic” scaffold-bioreactor system. We selected the temporomandibular joint (TMJ) condylar bone as our tissue model, because of its clinical importance and the challenges associated with its complex shape. Anatomically shaped scaffolds were generated from fully decellularized trabecular bone by using digitized clinical images, seeded with hMSCs, and cultured with interstitial flow of culture medium. A bioreactor with a chamber in the exact shape of a human TMJ was designed for controllable perfusion throughout the engineered construct. By 5 weeks of cultivation, tissue growth was evidenced by the formation of confluent layers of lamellar bone (by scanning electron microscopy), markedly increased volume of mineralized matrix (by quantitative microcomputer tomography), and the formation of osteoids (histologically). Within bone grafts of this size and complexity cells were fully viable at a physiologic density, likely an important factor of graft function. Moreover, the density and architecture of bone matrix correlated with the intensity and pattern of the interstitial flow, as determined in experimental and modeling studies. This approach has potential to overcome a critical hurdle—in vitro cultivation of viable bone grafts of complex geometries—to provide patient-specific bone grafts for craniofacial and orthopedic reconstructions. PMID:19820164

  5. Effortless effort in bone regeneration: a review.

    PubMed

    Nazirkar, Girish; Singh, Shailendra; Dole, Vinaykumar; Nikam, Akhilesh

    2014-06-01

    Since the beginning of the 20th century, the concept of osteoconduction in bony changes in the oral cavity showed a wide range of biomaterials and their osteoinductive potential that emerged gradually and has to a large extent improved the quality of the bone prior to the placement of an implant. Alveolar bone loss is a major concern after tooth extraction in patients and therefore atraumatic extraction procedures should be followed to avoid further bone loss. To overcome the alveolar bone loss and to augment support for placing dental implants, many bone regenerative substitutes are available such as allografts, autografts, xenografts, synthetic biomaterials and osteoactive agents. In light of the steady progress in bone grafting techniques and graft materials, it has become possible to improve the volume, width, and height of bone in deficient areas of the oral cavity. These advances in regenerative dentistry thus facilitate an easy and convenient placement of an implant in an ideal position and angulations resulting in superior esthetics and function. Bone grafting materials and their substitutes are the alternative filler materials, which facilitate to reduce additional surgical procedures, risks, chances of cross infection involved in placing autografts and allografts into the bony structures. This review literature highlights various biomaterials that are helpful in bone healing and thus create an anatomically favorable base for ideal implant placement. How to cite the article: Nazirkar G, Singh S, Dole V, Nikam A. Effortless effort in bone regeneration: A review. J Int Oral Health 2014;6(3):120-4. PMID:25083047

  6. Effortless Effort in Bone Regeneration: A Review

    PubMed Central

    Nazirkar, Girish; Singh, Shailendra; Dole, Vinaykumar; Nikam, Akhilesh

    2014-01-01

    Since the beginning of the 20th century, the concept of osteoconduction in bony changes in the oral cavity showed a wide range of biomaterials and their osteoinductive potential that emerged gradually and has to a large extent improved the quality of the bone prior to the placement of an implant. Alveolar bone loss is a major concern after tooth extraction in patients and therefore atraumatic extraction procedures should be followed to avoid further bone loss. To overcome the alveolar bone loss and to augment support for placing dental implants, many bone regenerative substitutes are available such as allografts, autografts, xenografts, synthetic biomaterials and osteoactive agents. In light of the steady progress in bone grafting techniques and graft materials, it has become possible to improve the volume, width, and height of bone in deficient areas of the oral cavity. These advances in regenerative dentistry thus facilitate an easy and convenient placement of an implant in an ideal position and angulations resulting in superior esthetics and function. Bone grafting materials and their substitutes are the alternative filler materials, which facilitate to reduce additional surgical procedures, risks, chances of cross infection involved in placing autografts and allografts into the bony structures. This review literature highlights various biomaterials that are helpful in bone healing and thus create an anatomically favorable base for ideal implant placement. How to cite the article: Nazirkar G, Singh S, Dole V, Nikam A. Effortless effort in bone regeneration: A review. J Int Oral Health 2014;6(3):120-4. PMID:25083047

  7. Studying Light Propagation in Bone for Treatment of Bone Cancers with Photodynamic Therapy

    NASA Astrophysics Data System (ADS)

    Rossi, Vincent; Gustafson, Scott; Jacques, Steven

    2008-05-01

    Photodynamic therapy makes use of light, photosensitizing agents, and oxygen as a selective means of treating cancer. The work presented is aimed at applying photodynamic therapy towards treatment of osteosarcoma in small animal clinics. To best facilitate clinical treatments, we must first understand how light propagates and how best to deliver adequate light to achieve phototoxic effects within bone. This work aims at characterizing how light propagates through bone and then applying that knowledge towards predicting light distributions in bone. Reflectance spectroscopy using an optical fiber source-collector pair is used to determine the scattering properties of bone tissues, and the absorption due to water and oxygenated and deoxygenated hemoglobin---native absorbers at visible and near-IR wavelengths. Resulting optical characterizations are then applied to a cylindrically symmetric Monte Carlo model in order to predict and guide the delivery of light within bone in order to achieve the desired phototoxic effect.

  8. Quantification of osteolytic bone lesions in a preclinical rat trial

    NASA Astrophysics Data System (ADS)

    Fränzle, Andrea; Bretschi, Maren; Bäuerle, Tobias; Giske, Kristina; Hillengass, Jens; Bendl, Rolf

    2013-10-01

    In breast cancer, most of the patients who died, have developed bone metastasis as disease progression. Bone metastases in case of breast cancer are mainly bone destructive (osteolytic). To understand pathogenesis and to analyse response to different treatments, animal models, in our case rats, are examined. For assessment of treatment response to bone remodelling therapies exact segmentations of osteolytic lesions are needed. Manual segmentations are not only time-consuming but lack in reproducibility. Computerized segmentation tools are essential. In this paper we present an approach for the computerized quantification of osteolytic lesion volumes using a comparison to a healthy reference model. The presented qualitative and quantitative evaluation of the reconstructed bone volumes show, that the automatically segmented lesion volumes complete missing bone in a reasonable way.

  9. Role of proton receptor OGR1 in bone response to metabolic acidosis?

    PubMed

    Jorgetti, Vanda; Drüeke, Tilman B; Ott, Susan M

    2016-03-01

    Chronic metabolic acidosis stimulates bone resorption, resulting in loss of calcium and bicarbonate from bone. Both osteoblasts and osteoclasts sense extracellular H(+) by the G-protein coupled receptor, OGR1, whose activation leads to increased bone resorption as well as decreased bone formation. Krieger et al. examined the effect of OGR1 knockout in mice. They found an unexpected increase in bone resorption, but nevertheless an increase in bone volume linked to enhanced bone formation. This discovery opens a window of opportunity to explore potential new anabolic treatments for patients with low bone mass. PMID:26880446

  10. Bone Mineral and Predictors of Bone Mass in White, Hispanic, and Asian Early Pubertal Girls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Racial differences in body size have been suggested to explain racial differences in bone in black and white youth. Previous studies of nonblack racial differences during growth used small cohorts spread over a large developmental age and cannot adequately address this question. Mater...

  11. Calcium-regulating hormones, bone mineral content, breaking load and trabecular remodeling are altered in growing pigs fed calcium-deficient diets.

    PubMed

    Eklou-Kalonji, E; Zerath, E; Colin, C; Lacroix, C; Holy, X; Denis, I; Pointillart, A

    1999-01-01

    Studies on calcium nutrition in appropriate large animal models can be directly relevant to humans. We have examined the effect of dietary Ca deficiency on various bone and bone-related variables, including plasma markers, histomorphometry, mineral content and breaking strength in pigs. Three groups of eight 38-d-old female pigs were fed adequate (0.9%; control), low (0.4%; LCa) or very low (0.1%; VLCa) Ca diets for 32 d. Plasma Ca significantly decreased over time only in the VLCa-deficient pigs. The concentrations of the parathyroid hormones (PTH) and calcitriol increased as Ca deficiency developed, and the plasma PTH and calcitriol levels varied inversely with dietary Ca. The total bone ash contents, bending moments, trabecular bone volume and the mineral apposition rate all decreased as the calcium intake decreased. The osteoclast surface areas were greater than those of controls in both Ca-deficient groups, whereas the osteoblast surface areas were greater only in the VLCa group. The plasma osteoblast-related markers (alkaline phosphatase, carboxy-terminal propeptide of type I procollagen and osteocalcin) were either greater or unaffected in the Ca-deficient pigs. The results indicate that deficient bone mineralization combined with an increased bone resorption led to bone loss and fragility. The differences in the changes in bone cells (number and activity) between LCa and VLCa groups might be due to differences (time and extent) of circulating PTH and calcitriol. The defective mineralization in both Ca-depleted groups resulted mainly from the lack of Ca because their osteoblast activity was either maintained or stimulated. The results also underline the progressive sensitivity of pigs to Ca supply and the usefulness of this model. PMID:9915898

  12. Bone banking and sterilization of bones

    NASA Astrophysics Data System (ADS)

    Minamisawa, I.; Itoman, M.; Maehara, H.; Kobayashi, A.; Watanabe, T.

    1995-08-01

    The use of banked bone (preserved allograft bone) is various and essential, because it has numerous advantages including the relative ease in retrieval a large amount of bone material and requisite shape and size. But bone banking and allografting must be promoted under obligation to stably supply safe and high-quality bone. To avoid transferring disease perfectly, irradiation sterilization is especially recommended at the present time.

  13. Bone Marrow Stress Decreases Osteogenic Progenitors.

    PubMed

    Ng, Adeline H; Baht, Gurpreet S; Alman, Benjamin A; Grynpas, Marc D

    2015-11-01

    Age-related bone loss may be a result of declining levels of stem cells in the bone marrow. Using the Col2.3Δtk (DTK) transgenic mouse, osteoblast depletion was used as a source of marrow stress in order to investigate the effects of aging on osteogenic progenitors which reside in the marrow space. Five-month-old DTK mice were treated with one or two cycles of ganciclovir to conditionally ablate differentiated osteoblasts, whereas controls were saline-treated. Treatment cycles were two weeks in length followed by four weeks of recovery. All animals were sacrificed at 8 months of age; bone marrow stromal cells (BMSCs) were harvested for cell culture and whole bones were excised for bone quality assessment. Colony-forming unit (CFU) assays were conducted to investigate the osteogenic potential of BMSC in vitro, and RNA was extracted to assess the expression of osteoblastic genes. Bone quality assessments included bone histomorphometry, TRAP staining, microcomputed tomography, and biomechanical testing. Osteoblast depletion decreased CFU-F (fibroblast), CFU-ALP (alkaline phosphatase), and CFU-VK (von Kossa) counts and BMSC osteogenic capacity in cell culture. Ex vivo, there were no differences in bone mineral density of vertebrae or femurs between treatment groups. Histology showed a decrease in bone volume and bone connectivity with repeated osteoblast depletion; however, this was accompanied by an increase in bone formation rate. There were no notable differences in osteoclast parameters or observed bone marrow adiposity. We have developed a model that uses bone marrow stress to mimic age-related decrease in osteogenic progenitors. Our data suggest that the number of healthy BMSCs and their osteogenic potential decline with repeated osteoblast depletion. However, activity of the remaining osteoblasts increases to compensate for this loss in progenitor osteogenic potential. PMID:26220824

  14. Hydrogel Delivery of Mesenchymal Stem Cell–Expressing Bone Morphogenetic Protein-2 Enhances Bone Defect Repair

    PubMed Central

    Hsiao, Hui-Yi; Yang, Shu-Rui; Brey, Eric M.; Chu, I-Ming

    2016-01-01

    Background: The application of bone tissue engineering for repairing bone defects has gradually shown some satisfactory progress. One of the concerns raising scientific attention is the poor supply of growth factors. A number of growth factor delivery approaches have been developed for promoting bone formation. However, there is no systematic comparison of those approaches on efficiency of neobone formation. In this study, the approaches using periosteum, direct supply of growth factors, or gene transfection of growth factors were evaluated to determine the osteogenic capacity on the repair of bone defect. Methods: In total, 42 male 21-week-old Sprague-Dawley rats weighing 250 to 400 g were used as the bone defect model to evaluate the bone repair efficiency. Various tissue engineered constructs of poly(ethylene glycol)-poly(l-lactic acid) (PEG-PLLA) copolymer hydrogel with periosteum, with external supply of bone morphogenetic protein-2 (BMP2), or with BMP2-transfected bone marrow–derived mesenchymal stem cells (BMMSCs) were filled in a 7-mm bone defect region. Animals were euthanized at 3 months, and the hydrogel constructs were harvested. The evaluation with histological staining and radiography analysis were performed for the volume of new bone formation. Results: The PEG-PLLA scaffold with BMMSCs promotes bone regeneration with the addition of periosteum. The group with BMP2-transfected BMMSCs demonstrated the largest volume of new bone among all the testing groups. Conclusions: Altogether, the results of this study provide the evidence that the combination of PEG-PLLA hydrogels with BMMSCs and sustained delivery of BMP2 resulted in the maximal bone regeneration. PMID:27622106

  15. Ostene, a New Alkylene Oxide Copolymer Bone Hemostatic Material, Does Not Inhibit Bone Healing

    PubMed Central

    Magyar, Clara E.; Aghaloo, Tara L.; Atti, Elisa; Tetradis, Sotirios

    2009-01-01

    OBJECTIVE In this study, we investigate the effects of a soft bone hemostatic wax comprised of water-soluble alkylene oxide copolymers (Ostene; Ceremed, Inc., Los Angeles, CA) on bone healing in a rat calvaria defect model. We compared the effects with a control (no hemostatic agent) and bone wax, an insoluble and nonresorbable material commonly used for bone hemostasis. METHODS Two bilateral 3-mm circular noncritical-sized defects were made in the calvariae of 30 rats. Alkylene oxide copolymer or bone wax was applied or no hemostatic material was used (control). After 3, 6, and 12 weeks, rats were sacrificed and the calvariae excised. Bone healing, expressed as fractional bone volume (± standard error of the mean), was measured by microcomputed tomography. RESULTS Immediate hemostasis was achieved equally with bone wax and alkylene oxide copolymer. Bone wax-filled defects remained unchanged at all time points with negligible healing observed. At 3 weeks, no evidence of alkylene oxide copolymer was observed at the application site, with fractional bone volume significantly greater than bone wax-treated defects (0.20 ± 0.03 versus 0.02 ± 0.01; P = 0.0003). At 6 and 12-weeks, alkylene oxide copolymer-treated defects continued to show significantly greater healing versus bone wax (0.18 ± 0.04 versus 0.05 ± 0.01 and 0.31 ± 0.04 versus 0.06 ± 0.02, respectively). At all time points, alkylene oxide copolymer-treated and control defects showed good healing with no significant difference. CONCLUSION Alkylene oxide copolymer is an effective hemostatic agent that does not inhibit osteogenesis or bone healing. PMID:18981846

  16. Vegetarian diets and bone status.

    PubMed

    Tucker, Katherine L

    2014-07-01

    Osteoporosis is a common chronic condition associated with progressive loss of bone mineral density (BMD) and compromised bone strength, with increasing risk of fracture over time. Vegetarian diets have been shown to contain lower amounts of calcium, vitamin D, vitamin B-12, protein, and n-3 (ω-3) fatty acids, all of which have important roles in maintaining bone health. Although zinc intakes are not necessarily lower quantitatively, they are considerably less bioavailable in vegetarian diets, which suggests the need for even higher intakes to maintain adequate status. At the same time, healthy vegetarian diets tend to contain more of several protective nutrients, including magnesium, potassium, vitamin K, and antioxidant and anti-inflammatory phytonutrients. On balance, there is evidence that vegetarians, and particularly vegans, may be at greater risk of lower BMD and fracture. Attention to potential shortfall nutrients through the careful selection of foods or fortified foods or the use of supplements can help ensure healthy bone status to reduce fracture risk in individuals who adhere to vegetarian diets. PMID:24898237

  17. Bone density and anisotropy affect periprosthetic cement and bone stresses after anatomical glenoid replacement: A micro finite element analysis.

    PubMed

    Chevalier, Yan; Santos, Inês; Müller, Peter E; Pietschmann, Matthias F

    2016-06-14

    Glenoid loosening is still a main complication for shoulder arthroplasty. We hypothesize that cement and bone stresses potentially leading to fixation failure are related not only to glenohumeral conformity, fixation design or eccentric loading, but also to bone volume fraction, cortical thickness and degree of anisotropy in the glenoid. In this study, periprosthetic bone and cement stresses were computed with micro finite element models of the replaced glenoid depicting realistic bone microstructure. These models were used to quantify potential effects of bone microstructural parameters under loading conditions simulating different levels of glenohumeral conformity and eccentric loading simulating glenohumeral instability. Results show that peak cement stresses were achieved near the cement-bone interface in all loading schemes. Higher stresses within trabecular bone tissue and cement mantle were obtained within specimens of lower bone volume fraction and in regions of low anisotropy, increasing with decreasing glenohumeral conformity and reaching their maxima below the keeled design when the load is shifted superiorly. Our analyses confirm the combined influences of eccentric load shifts with reduced bone volume fraction and anisotropy on increasing periprosthetic stresses. They finally suggest that improving fixation of glenoid replacements must reduce internal cement and bone tissue stresses, in particular in glenoids of low bone density and heterogeneity. PMID:27087675

  18. Bioactive Silica Nanoparticles Reverse Age-Associated Bone Loss in Mice

    PubMed Central

    Vikulina, Tatyana; Roser-Page, Susanne; Lee, Jin-Kyu; Beck, George R.

    2015-01-01

    We recently reported that in vitro, engineered 50 nm spherical silica nanoparticles promote the differentiation and activity of bone building osteoblasts but suppress that of bone-resorbing osteoclasts. Furthermore, these nanoparticles promote bone accretion in young mice in vivo. In the present study the capacity of these nanoparticles to reverse bone loss in aged mice, a model of human senile osteoporosis, was investigated. Aged mice received nanoparticles weekly and bone mineral density (BMD), bone structure, and bone turnover was quantified. Our data revealed a significant increase in BMD, bone volume, and biochemical markers of bone formation. Biochemical and histological examinations failed to identify any abnormalities caused by nanoparticle administration. Our studies demonstrate that silica nanoparticles effectively blunt and reverse age-associated bone loss in mice by a mechanism involving promotion of bone formation. The data suggest that osteogenic silica nanoparticles may be a safe and effective therapeutic for counteracting age-associated bone loss. PMID:25680544

  19. Building a bone μCT images atlas for micro-architecture recognition

    NASA Astrophysics Data System (ADS)

    Freuchet, E.; Recur, B.; Guédon, Jp.; Kingston, A.; Autrusseau, F.; Amouriq, Y.

    2015-03-01

    Trabecular bone and its micro-architecture are of prime importance for health. Changes of bone micro-architecture are linked to different pathological situations like osteoporosis and begin now to be understood. In a previous paper, we started to investigate the relationships between bone and vessels and we also proposed to build a Bone Atlas. This study describes how to proceed for the elaboration and use of such an atlas. Here, we restricted the Atlas to legs (tibia, femur) of rats in order to work with well known geometry of the bone micro-architecture. From only 6 acquired bone, 132 trabecular bone volumes were generated using simple mathematical morphology tools. The variety and veracity of the created micro-architecture volumes is presented in this paper. Medical application and final goal would be to determinate bone micro-architecture with some angulated radiographs (3 or 4) and to easily diagnose the bone status (healthy, pathological or healing bone...).

  20. Spine Fusion Using Cell Matrix Composites Enriched in Bone Marrow-Derived Cells

    PubMed Central

    Nitto, Hironori; Matsukura, Yoichi; Boehm, Cynthia; Valdevit, Antonio; Kambic, Helen; Davros, William; Powell, Kimerly; Easley, Kirk

    2005-01-01

    Bone marrow-derived cells including osteoblastic progenitors can be concentrated rapidly from bone marrow aspirates using the surface of selected implantable matrices for selective cell attachment. Concentration of cells in this way to produce an enriched cellular composite graft improves graft efficacy. The current study was designed to test the hypothesis that the biologic milieu of a bone marrow clot will significantly improve the efficacy of such a graft. An established posterior spinal fusion model and cancellous bone matrix was used to compare an enriched cellular composite bone graft alone, bone matrix plus bone marrow clot, and an enriched bone matrix composite graft plus bone marrow clot. Union score, quantitative computed tomography, and mechanical testing were used to define outcome. The union score for the enriched bone matrix plus bone marrow clot composite was superior to the enriched bone matrix alone and the bone matrix plus bone marrow clot. The enriched bone matrix plus bone marrow clot composite also was superior to the enriched bone matrix alone in fusion volume and in fusion area. These data confirm that the addition of a bone marrow clot to an enriched cell-matrix composite graft results in significant improvement in graft performance. Enriched composite grafts prepared using this strategy provide a rapid, simple, safe, and inexpensive method for intraoperative concentration and delivery of bone marrow-derived cells and connective tissue progenitors that may improve the outcome of bone grafting. PMID:12567137

  1. [Bone quantitative ultrasound].

    PubMed

    Matsukawa, Mami

    2016-01-01

    The conventional ultrasonic bone densitometry system can give us information of bone as ultrasonic wave velocity and attenuation. However, the data reflect both structural and material properties of bone. In order to focus only on the bone matrix properties without the effect of bone structure, studies of microscopic Brillouin scattering technique are introduced. The wave velocity in a trabecula was anisotropic and depended on the position and structure of the cancellous bone. The glycation also affected on the wave velocities in bone. As a new bone quality, the piezoelectricity of bone is also discussed. PMID:26728531

  2. Peak bone strength is influenced by calcium intake in growing rats.

    PubMed

    Viguet-Carrin, S; Hoppler, M; Membrez Scalfo, F; Vuichoud, J; Vigo, M; Offord, E A; Ammann, P

    2014-11-01

    In this study we investigated the effect of supplementing the diet of the growing male rat with different levels of calcium (from low to higher than recommended intakes at constant Ca/P ratio), on multiple factors (bone mass, strength, size, geometry, material properties, turnover) influencing bone strength during the bone accrual period. Rats, age 28days were supplemented for 4weeks with high Ca (1.2%), adequate Ca (0.5%) or low Ca level (0.2%). Bone metabolism and structural parameters were measured. No changes in body weight or food intake were observed among the groups. As anticipated, compared to the adequate Ca intake, low-Ca intake had a detrimental impact on bone growth (33.63 vs. 33.68mm), bone strength (-19.7% for failure load), bone architecture (-58% for BV/TV) and peak bone mass accrual (-29% for BMD) due to the hormonal disruption implied in Ca metabolism. In contrast, novel, surprising results were observed in that higher than adequate Ca intake resulted in improved peak bone strength (106 vs. 184N/mm for the stiffness and 61 vs. 89N for the failure load) and bone material properties (467 vs. 514mPa for tissue hardness) but these effects were not accompanied by changes in bone mass, size, microarchitecture or bone turnover. Hormonal factors, IGF-I and bone modeling were also evaluated. Compared to the adequate level of Ca, IGF-I level was significantly lower in the low-Ca intake group and significantly higher in the high-Ca intake group. No detrimental effects of high Ca were observed on bone modeling (assessed by histomorphometry and bone markers), at least in this short-term intervention. In conclusion, the decrease in failure load in the low calcium group can be explained by the change in bone geometry and bone mass parameters. Thus, improvements in mechanical properties can be explained by the improved quality of intrinsic bone tissue as shown by nanoindentation. These results suggest that supplemental Ca may be beneficial for the attainment of

  3. A prospective study on the effectiveness of newly developed autogenous tooth bone graft material for sinus bone graft procedure

    PubMed Central

    Jun, Sang-Ho; Ahn, Jin-Soo; Lee, Jae-Il; Ahn, Kyo-Jin; Yun, Pil-Young

    2014-01-01

    PURPOSE The purpose of this prospective study was to evaluate the effectiveness of newly developed autogenous tooth bone graft material (AutoBT)application for sinus bone graft procedure. MATERIALS AND METHODS The patients with less than 5.0 mm of residual bone height in maxillary posterior area were enrolled. For the sinus bone graft procedure, Bio-Oss was grafted in control group and AutoBT powder was grafted in experimental group. Clinical and radiographic examination were done for the comparison of grafted materials in sinus cavity between groups. At 4 months after sinus bone graft procedure, biopsy specimens were analyzed by microcomputed tomography and histomorphometric examination for the evaluation of healing state of bone graft site. RESULTS In CT evaluation, there was no difference in bone density, bone height and sinus membrane thickness between groups. In microCT analysis, there was no difference in total bone volume, new bone volume, bone mineral density of new bone between groups. There was significant difference trabecular thickness (0.07 µm in Bio-Oss group Vs. 0.08 µm in AutoBT group) (P=.006). In histomorphometric analysis, there was no difference in new bone formation, residual graft material, bone marrow space between groups. There was significant difference osteoid thickness (8.35 µm in Bio-Oss group Vs. 13.12 µm in AutoBT group) (P=.025). CONCLUSION AutoBT could be considered a viable alternative to the autogenous bone or other bone graft materials in sinus bone graft procedure. PMID:25551014

  4. Controlling Bone Graft Substitute Microstructure to Improve Bone Augmentation.

    PubMed

    Sheikh, Zeeshan; Drager, Justin; Zhang, Yu Ling; Abdallah, Mohamed-Nur; Tamimi, Faleh; Barralet, Jake

    2016-07-01

    Vertical bone augmentation procedures are frequently carried out to allow successful placement of dental implants in otherwise atrophic ridges and represent one of the most common bone grafting procedures currently performed. Onlay autografting is one of the most prevalent and predictable techniques to achieve this; however, there are several well documented complications and drawbacks associated with it and synthetic alternatives are being sought. Monetite is a bioresorbable dicalcium phosphate with osteoconductive and osteoinductive potential that has been previously investigated for onlay bone grafting and it is routinely made by autoclaving brushite to simultaneously sterilize and phase convert. In this study, monetite disc-shaped grafts are produced by both wet and dry heating methods which alter their physical properties such as porosity, surface area, and mechanical strength. Histological observations after 12 weeks of onlay grafting on rabbit calvaria reveal higher bone volume (38%) in autoclaved monetite grafts in comparison with the dry heated monetite grafts (26%). The vertical bone height gained is similar for both the types of monetite grafts (up to 3.2 mm). However, it is observed that the augmented bone height is greater in the lateral than the medial areas of both types of monetite grafts. It is also noted that the higher porosity of autoclaved monetite grafts increases the bioresorbability, whereas the dry heated monetite grafts having lower porosity but higher surface area resorb to a significantly lesser extent. This study provides information regarding two types of monetite onlay grafts prepared with different physical properties that can be further investigated for clinical vertical bone augmentation applications. PMID:27214877

  5. 21 CFR 314.126 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...-evident (general anesthetics, drug metabolism). (3) The method of selection of subjects provides adequate... respect to pertinent variables such as age, sex, severity of disease, duration of disease, and use of... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Adequate and well-controlled studies....

  6. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  7. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  8. Calculation of the Cost of an Adequate Education in Kentucky: A Professional Judgment Approach

    ERIC Educational Resources Information Center

    Verstegen, Deborah A.

    2004-01-01

    What is an adequate education and how much does it cost? In 1989, Kentucky's State Supreme Court found the entire system of education unconstitutional--"all of its parts and parcels". The Court called for all children to have access to an adequate education, one that is uniform and has as its goal the development of seven capacities, including:…

  9. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Attending veterinarian and adequate veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a)...

  10. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Attending Veterinarian and Adequate Veterinary Care §...

  11. 75 FR 69648 - Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... SAFETY BOARD Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers... TO THE SECRETARY OF ENERGY Safety Analysis Requirements for Defining Adequate Protection for the... safety analysis, or DSA, is to be prepared for every DOE nuclear facility. This DSA, once approved by...

  12. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  13. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  14. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  15. Autologous implantation of BMP2-expressing dermal fibroblasts to improve bone mineral density and architecture in rabbit long bones.

    PubMed

    Ishihara, Akikazu; Weisbrode, Steve E; Bertone, Alicia L

    2015-10-01

    Cell-mediated gene therapy may treat bone fragility disorders. Dermal fibroblasts (DFb) may be an alternative cell source to stem cells for orthopedic gene therapy because of their rapid cell yield and excellent plasticity with bone morphogenetic protein-2 (BMP2) gene transduction. Autologous DFb or BMP2-expressing autologous DFb were administered in twelve rabbits by two delivery routes; a transcortical intra-medullar infusion into tibiae and delayed intra-osseous injection into femoral drill defects. Both delivery methods of DFb-BMP2 resulted in a successful cell engraftment, increased bone volume, bone mineral density, improved trabecular bone microarchitecture, greater bone defect filling, external callus formation, and trabecular surface area, compared to non-transduced DFb or no cells. Cell engraftment within trabecular bone and bone marrow tissue was most efficiently achieved by intra-osseous injection of DFb-BMP2. Our results suggested that BMP2-expressing autologous DFb have enhanced efficiency of engraftment in target bones resulting in a measurable biologic response by the bone of improved bone mineral density and bone microarchitecture. These results support that autologous implantation of DFb-BMP2 warrants further study on animal models of bone fragility disorders, such as osteogenesis imperfecta and osteoporosis to potentially enhance bone quality, particularly along with other gene modification of these diseases. PMID:25418909

  16. High-fat diet causes bone loss in young mice by promoting osteoclastogenesis through alteration of the bone marrow environment.

    PubMed

    Shu, Lei; Beier, Eric; Sheu, Tzong; Zhang, Hengwei; Zuscik, Michael J; Puzas, Edward J; Boyce, Brendan F; Mooney, Robert A; Xing, Lianping

    2015-04-01

    Obesity is a severe health problem in children, afflicting several organ systems including bone. However, the role of obesity on bone homeostasis and bone cell function in children has not been studied in detail. Here we used young mice fed a high-fat diet (HFD) to model childhood obesity and investigate the effect of HFD on the phenotype of cells within the bone marrow environment. Five-week-old male mice were fed a HFD for 3, 6, and 12 weeks. Decreased bone volume was detected after 3 weeks of HFD treatment. After 6 and 12 weeks, HFD-exposed mice had less bone mass and increased osteoclast numbers. Bone marrow cells, but not spleen cells, from HFD-fed mice had increased osteoclast precursor frequency, elevated osteoclast formation, and bone resorption activity, as well as increased expression of osteoclastogenic regulators including RANKL, TNF, and PPAR-gamma. Bone formation rate and osteoblast and adipocyte numbers were also increased in HFD-fed mice. Isolated bone marrow cells also had a corresponding elevation in the expression of positive regulators of osteoblast and adipocyte differentiation. Our findings indicate that in juvenile mice, HFD-induced bone loss is mainly due to increased osteoclast bone resorption by affecting the bone marrow microenvironment. Thus, targeting osteoclast formation may present a new therapeutic approach for bone complications in obese children. PMID:25673503

  17. Bone scan appearances following bone and bone marrow biopsy

    SciTech Connect

    McKillop, J.H.; Maharaj, D.; Boyce, B.F.; Fogelman, I.

    1984-01-01

    Bone marrow and bone biopsies are performed not infrequently in patients referred for bone scans and represent a potential cause of a ''false positive'' focal abnormality on the bone scan. The authors have therefore examined the scan appearances in a series of patients who had undergone either sternal marrow biopsy, (Salah needle, diameter 1.2 mm) trephine iliac crest marrow biopsy (Jamshidi 11 gauge needle, diameter 3.5 mm) or a transiliac bone biopsy (needle diameter 8 mm). Of 18 patients studied 1 to 45 days after sternal marrow 17 had normal scan appearances at the biopsy site and 1 had a possible abnormality. None of 9 patients studied 4 to 19 days after trephine iliac crest marrow biopsy had a hot spot at the biopsy site. A focal scan abnormality was present at the biopsy site in 9/11 patients studied 5 to 59 days after a trans iliac bone biopsy. No resultant scan abnormality was seen in 4 patients imaged within 3 days of the bone biopsy or in 3 patients imaged 79 to 138 days after the procedure. Bone marrow biopsy of the sternum or iliac crest does not usually cause bone scan abnormalities. A focal abnormality at the biopsy site is common in patients imaged 5 days to 2 months after bone biopsy. The gauge of the needle employed in the biopsy and thus the degree of bone trauma inflicted, is likely to be main factor determining the appearance of bone scan abnormalities at the biopsy site.

  18. Bovine hemoglobin as the sole source of dietary iron does not support adequate iron status in copper-adequate or copper-deficient rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This experiment was designed to determine whether hemoglobin as the sole source of dietary iron (Fe) could sustain normal Fe status in growing rats. Because adequate copper (Cu) status is required for efficient Fe absorption in the rat, we also determined the effects of Cu deficiency on Fe status of...

  19. The Role of Resorbable Plate and Artificial Bone Substitute in Reconstruction of Large Orbital Floor Defect

    PubMed Central

    Kwon, Ho; Kim, Ho Jun; Jeong, Yeon Jin; Jung, Sung-No

    2016-01-01

    It is essential to reduce and reconstruct bony defects adequately in large orbital floor fracture and defect. Among many reconstructive methods, alloplastic materials have attracted attention because of their safety and ease of use. We have used resorbable plates combined with artificial bone substitutes in large orbital floor defect reconstructions and have evaluated their long-term reliability compared with porous polyethylene plate. A total of 147 patients with traumatic orbital floor fracture were included in the study. Surgical results were evaluated by clinical evaluations, exophthalmometry, and computed tomography at least 12 months postoperatively. Both orbital floor height discrepancy and orbital volume change were calculated and compared with preoperative CT findings. The average volume discrepancy and vertical height discrepancies were not different between two groups. Also, exophthalmometric measurements were not significantly different between the two groups. No significant postoperative complication including permanent diplopia, proptosis, and enophthalmos was noted. Use of a resorbable plate with an artificial bone substitute to repair orbital floor defects larger than 2.5 cm2 in size yielded long-lasting, effective reconstruction without significant complications. We therefore propose our approach as an effective alternative method for large orbital floor reconstructions. PMID:27517041

  20. Composites structures for bone tissue reconstruction

    NASA Astrophysics Data System (ADS)

    Neto, W.; Santos, João.; Avérous, L.; Schlatter, G.; Bretas, Rosario.

    2015-05-01

    The search for new biomaterials in the bone reconstitution field is growing continuously as humane life expectation and bone fractures increase. For this purpose, composite materials with biodegradable polymers and hydroxyapatite (HA) have been used. A composite material formed by a film, nanofibers and HA has been made. Both, the films and the non-woven mats of nanofibers were formed by nanocomposites made of butylene adipate-co-terephthalate (PBAT) and HA. The techniques used to produce the films and nanofibers were spin coating and electrospinning, respectively. The composite production and morphology were evaluated. The composite showed an adequate morphology and fibers size to be used as scaffold for cell growth.

  1. Composites structures for bone tissue reconstruction

    SciTech Connect

    Neto, W.; Santos, João; Avérous, L.; Schlatter, G.; Bretas, Rosario

    2015-05-22

    The search for new biomaterials in the bone reconstitution field is growing continuously as humane life expectation and bone fractures increase. For this purpose, composite materials with biodegradable polymers and hydroxyapatite (HA) have been used. A composite material formed by a film, nanofibers and HA has been made. Both, the films and the non-woven mats of nanofibers were formed by nanocomposites made of butylene adipate-co-terephthalate (PBAT) and HA. The techniques used to produce the films and nanofibers were spin coating and electrospinning, respectively. The composite production and morphology were evaluated. The composite showed an adequate morphology and fibers size to be used as scaffold for cell growth.

  2. Biomechanical optimization of a custom-made positioning and fixing bone plate for Le Fort I osteotomy by finite element analysis.

    PubMed

    Huang, Shao-Fu; Lo, Lun-Jou; Lin, Chun-Li

    2016-01-01

    This study integrates image-processing, finite element (FE) analysis, optimization and CAM techniques to develop a bone plate that can provide precise positioning and fixation for the Le Fort I osteotomy. Two FE 3D models using commercial mini-plate and continuous bone plates were generated by integrating computed tomography images and CAD system for simulations under the worst load condition. The goal driven optimization method was used to examine the system performance using certain minimum output values for relative micro-movement between the two maxillary bone segments and stress for the bone plate to seek maximum reduction volume in a continuous plate. The simulation results indicated that the maximum stress/relative micro-movement was 1269.20MPa/133.66μm and 418.37MPa/92.37μm for the commercial straight mini-plate and continuous fixation types, respectively. The optimal design plate found the volume reduction rate reach 24.3% compared to the continuous bone plate and the decreased variations in stress/relative micro-movement were 65.14% (442.36MPa) and 29.36% (96.53μm) when compared to values obtained from the commercial mini-plate plate. The optimal bone plate can be manufactured using a 5-axes milling machine and fixed onto the freed separate maxillary segments of a rapid prototyping model to provide precise positioning/fixation and present adequate strength/stability in the Le Fort I osteotomy. PMID:26609803

  3. 45 CFR 1159.15 - Who has the responsibility for maintaining adequate technical, physical, and security safeguards...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... of maintaining adequate technical, physical, and security safeguards to prevent...

  4. Is bone transplantation the gold standard for repair of alveolar bone defects?

    PubMed

    Raposo-Amaral, Cassio Eduardo; Bueno, Daniela Franco; Almeida, Ana Beatriz; Jorgetti, Vanda; Costa, Cristiane Cabral; Gouveia, Cecília Helena; Vulcano, Luiz Carlos; Fanganiello, Roberto D; Passos-Bueno, Maria Rita; Alonso, Nivaldo

    2014-01-01

    New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate), compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7) defects were repaired with autogenous bone grafts; Group 2 (n = 5) defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5) defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5) defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6) defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2-5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01) and 38.35% ± 19.59% (p = 0.06) of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30) and 61.80% ± 2.14% (p = 0.88) of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone. PMID:24551445

  5. Is bone transplantation the gold standard for repair of alveolar bone defects?

    PubMed Central

    Raposo-Amaral, Cassio Eduardo; Bueno, Daniela Franco; Almeida, Ana Beatriz; Jorgetti, Vanda; Costa, Cristiane Cabral; Gouveia, Cecília Helena; Vulcano, Luiz Carlos; Fanganiello, Roberto D; Passos-Bueno, Maria Rita

    2014-01-01

    New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate), compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7) defects were repaired with autogenous bone grafts; Group 2 (n = 5) defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5) defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5) defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6) defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01) and 38.35% ± 19.59% (p = 0.06) of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30) and 61.80% ± 2.14% (p = 0.88) of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone. PMID:24551445

  6. Effect of chronic metabolic acidosis on bone density and bone architecture in vivo in rats.

    PubMed

    Gasser, Jürg A; Hulter, Henry N; Imboden, Peter; Krapf, Reto

    2014-03-01

    Chronic metabolic acidosis (CMA) might result in a decrease in vivo in bone mass based on its reported in vitro inhibition of bone mineralization, bone formation, or stimulation of bone resorption, but such data, in the absence of other disorders, have not been reported. CMA also results in negative nitrogen balance, which might decrease skeletal muscle mass. This study analyzed the net in vivo effects of CMA's cellular and physicochemical processes on bone turnover, trabecular and cortical bone density, and bone microarchitecture using both peripheral quantitative computed tomography and μCT. CMA induced by NH4Cl administration (15 mEq/kg body wt/day) in intact and ovariectomized (OVX) rats resulted in stable CMA (mean Δ[HCO3(-)]p = 10 mmol/l). CMA decreased plasma osteocalcin and increased TRAP5b in intact and OVX animals. CMA decreased total volumetric bone mineral density (vBMD) after 6 and 10 wk (week 10: intact normal +2.1 ± 0.9% vs. intact acidosis -3.6 ± 1.2%, P < 0.001), an effect attributable to a decrease in cortical thickness and, thus, cortical bone mass (no significant effect on cancellous vBMD, week 10) attributed to an increase in endosteal bone resorption (nominally increased endosteal circumference). Trabecular bone volume (BV/TV) decreased significantly in both CMA groups at 6 and 10 wk, associated with a decrease in trabecular number. CMA significantly decreased muscle cross-sectional area in the proximal hindlimb at 6 and 10 wk. In conclusion, chronic metabolic acidosis induces a large decrease in cortical bone mass (a prime determinant of bone fragility) in intact and OVX rats and impairs bone microarchitecture characterized by a decrease in trabecular number. PMID:24352505

  7. Three-Dimensional Geometric Analysis of Felid Limb Bone Allometry

    PubMed Central

    Doube, Michael; Conroy, Alexis Wiktorowicz; Christiansen, Per; Hutchinson, John R.; Shefelbine, Sandra

    2009-01-01

    Background Studies of bone allometry typically use simple measurements taken in a small number of locations per bone; often the midshaft diameter or joint surface area is compared to body mass or bone length. However, bones must fulfil multiple roles simultaneously with minimum cost to the animal while meeting the structural requirements imposed by behaviour and locomotion, and not exceeding its capacity for adaptation and repair. We use entire bone volumes from the forelimbs and hindlimbs of Felidae (cats) to investigate regional complexities in bone allometry. Method/Principal Findings Computed tomographic (CT) images (16435 slices in 116 stacks) were made of 9 limb bones from each of 13 individuals of 9 feline species ranging in size from domestic cat (Felis catus) to tiger (Panthera tigris). Eleven geometric parameters were calculated for every CT slice and scaling exponents calculated at 5% increments along the entire length of each bone. Three-dimensional moments of inertia were calculated for each bone volume, and spherical radii were measured in the glenoid cavity, humeral head and femoral head. Allometry of the midshaft, moments of inertia and joint radii were determined. Allometry was highly variable and related to local bone function, with joint surfaces and muscle attachment sites generally showing stronger positive allometry than the midshaft. Conclusions/Significance Examining whole bones revealed that bone allometry is strongly affected by regional variations in bone function, presumably through mechanical effects on bone modelling. Bone's phenotypic plasticity may be an advantage during rapid evolutionary divergence by allowing exploitation of the full size range that a morphotype can occupy. Felids show bone allometry rather than postural change across their size range, unlike similar-sized animals. PMID:19270749

  8. Facts about Broken Bones

    MedlinePlus

    ... las fracturas de huesos Your bones are tough stuff — but even tough stuff can break. Like a wooden pencil, bones will ... that? Get a lot of physical activity, especially stuff like jumping and running. Feed your bones the ...

  9. Bone marrow aspiration

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003658.htm Bone marrow aspiration To use the sharing features on this page, please enable JavaScript. Bone marrow is the soft tissue inside bones that helps ...

  10. Bone density scan (image)

    MedlinePlus

    ... bone the higher the risk of fractures. A bone scan, along with a patient's medical history, is a ... and whether any preventative treatment is needed. A bone density scan has the advantage of being painless and exposing ...

  11. Smoking and Bone Health

    MedlinePlus

    ... direct relationship between tobacco use and decreased bone density. Analyzing the impact of cigarette smoking on bone ... hard to determine whether a decrease in bone density is due to smoking itself or to other ...

  12. Menopause and Bone Loss

    MedlinePlus

    ... You reach your highest bone mass (size and density) at about age 30. Then, sometime between age ... your bones, your doctor may do a bone density test (DEXA scan). This test gives exact measurements ...

  13. [Evaluation of bone sterngth].

    PubMed

    Mashiba, Tasuku

    2016-01-01

    Biomechanical testing of the bone provides the most important and direct information about bone strength. This article explains biomechanical priciples including structural mechanical properties and intrinsic material properties, and serves actual biomechanical testing tedhniques for bone specimens. PMID:26728529

  14. Bone marrow biopsy

    MedlinePlus

    Biopsy - bone marrow ... A bone marrow biopsy may be done in the health care provider's office or in a hospital. The sample may be taken from the pelvic or breast bone. Sometimes, other areas are used. Marrow is removed ...

  15. Experiment K305: Quantitative analysis of selected bone parameters. Supplement 2: Bone elongation rate and bone mass in metaphysis of long bones

    NASA Technical Reports Server (NTRS)

    Jee, W. S. S.; Kimmel, D. B.; Smith, C.; Dell, R. B.

    1981-01-01

    The proximal humeral metaphysis of rats from time periods recovery plus zero days (R+0), recovery plus six days (R+6), and recovery plus twenty nine days (R+29) was analyzed. The volume of calcified cartilage and bone in flight and synchronous controls was reduced in groups R+0 and R+6, but was normal in group R+29. The number of functional bone cells (osteoblasts and osteoclasts) was decreased in proportion to the amount of bone in the early groups, and was normal in the last group. The fatty marrow volume was increased only in flight animals of groups R+0 and R+6, but was normal in the R+29 group. Accumulation of excess fatty marrow was seen only in flight animals. The decreased amount of bone and calcified cartilage is believed to be the result of a temporarily slowed or arrested production of calcified cartilage as a substrate for bone formation. This would have resulted from slowed bone elongation during flight and synchronous control conditions. Bone elongation returned to normal by twenty nine days after return.

  16. High-resolution CT of temporal bone trauma

    SciTech Connect

    Holland, B.A.; Brant-Zawadzki, M.

    1984-08-01

    Computed tomographic (CT) finding in 18 patients with temporal bone trauma were reviewed. Eight patients suffered longitudinal fractures of the petrous bone, which were associated with ossicular dislocation in two patients. Transverse fractures were detected in six patients, with a contralateral mastoid fracture in one patient. In four patients, the fractures were restricted to the mastoid region. Of the 14 patients in whom adequate neurologic evaluation was available, seven had a permanent facial nerve or hearing deficit while five suffered at least a transient neurologic deficit related to the temporal bone trauma. Routine head CT (10 mm sections) demonstrated only eight of 19 petrous bone injuries. Evidence of brain trauma or extra-axial hemotoma was seen in 12 patients. In 13 cases, high-resolution CT was also performed, demonstrating temporal bone injuries in all. This latter technique allows rapid and detailed evaluation of temporal bone trauma.

  17. The Effect of Potassium Bicarbonate on Bone and Several Physiological Systems During Immobilisation

    ClinicalTrials.gov

    2012-01-10

    Bone Metabolism; Acid- Base Balance; Muscle Metabolism; Muscle Strenght, Muscle Power and Muscle Volume; Protein Metabolim; Body Weight and Body Composition; Cardiovascular System; Neuro- Vestibular System

  18. Relationships among maxillofacial morphologies, bone properties, and bone metabolic markers in patients with jaw deformities.

    PubMed

    Saito, D; Mikami, T; Oda, Y; Hasebe, D; Nishiyama, H; Saito, I; Kobayashi, T

    2016-08-01

    The aim of this study was to determine the relationships among bone properties, bone metabolic markers, and types of jaw deformity. The subjects were 55 female patients with jaw deformities. Skeletal morphology was examined using lateral cephalograms, and the patients were divided into three groups according to the type of anteroposterior skeletal pattern. Serum osteocalcin, bone alkaline phosphatase, and tartrate-resistant acid phosphatase isoform 5b, as well as deoxypyridinoline in urine, were measured as bone metabolic markers. Quantitative ultrasound (QUS) measurements were used to assess bone properties at the calcaneal bone. The bone volume and bone density of the condylar process were measured in 43 patients by computed tomography. There were no significant differences in bone metabolic markers and QUS parameters between the groups, although bone formation and resorption markers tended to be higher in patients with a protrusive mandible. On the other hand, patients with mandibular retrusion had a higher tendency to have small and dense condylar processes. In conclusion, the results suggest that growth depression or a degenerative change in the mandibular condyle is involved in the pathogenesis of mandibular retrusion, although risk factors for progressive condylar resorption were not determined. PMID:26972158

  19. Dietary dried plum increases bone mass, suppresses proinflammatory cytokines and promotes attainment of peak bone mass in male mice.

    PubMed

    Shahnazari, Mohammad; Turner, Russell T; Iwaniec, Urszula T; Wronski, Thomas J; Li, Min; Ferruzzi, Mario G; Nissenson, Robert A; Halloran, Bernard P

    2016-08-01

    Nutrition is an important determinant of bone health and attainment of peak bone mass. Diets containing dried plum (DP) have been shown to increase bone volume and strength. These effects may be linked to the immune system and DP-specific polyphenols. To better understand these relationships, we studied DP in skeletally mature (6-month-old) and growing (1- and 2-month-old) C57Bl/6 male mice. In adult mice, DP rapidly (<2 weeks) increased bone volume (+32%) and trabecular thickness (+24%). These changes were associated with decreased osteoclast surface (Oc.S/BS) and decreased serum CTX, a marker of bone resorption. The reduction in Oc.S/BS was associated with a reduction in the osteoclast precursor pool. Osteoblast surface (Ob.S/BS) and bone formation rate were also decreased suggesting that the gain in bone in adult mice is a consequence of diminished bone resorption and formation, but resorption is reduced more than formation. The effects of DP on bone were accompanied by a decline in interleukins, TNF and MCP-1, suggesting that DP is acting in part through the immune system to suppress inflammatory activity and reduce the size of the osteoclast precursor pool. Feeding DP was accompanied by an increase in plasma phenolics, some of which have been shown to stimulate bone accrual. In growing and young adult mice DP at levels as low as 5% of diet (w/w) increased bone volume. At higher levels (DP 25%), bone volume was increased by as much as 94%. These data demonstrate that DP feeding dramatically increases peak bone mass during growth. PMID:27239754

  20. Assessment of the autogenous bone graft for sinus elevation

    PubMed Central

    Peng, Wang; Cho, Hyun-Young; Pae, Sang-Pill; Jung, Bum-Sang; Cho, Hyun-Woo; Seo, Ji-Hoon

    2013-01-01

    Objectives The posterior maxillary region often provides a limited bone volume for dental implants. Maxillary sinus elevation via inserting a bone graft through a window opened in the lateral sinus wall has become the most common surgical procedure for increasing the alveolar bone height in place of dental implants in the posterior maxillary region. The purpose of this article is to assess the change of bone volume and the clinical effects of dental implant placement in sites with maxillary sinus floor elevation and autogenous bone graft through the lateral window approach. Materials and Methods In this article, the analysis data were collected from 64 dental implants that were placed in 24 patients with 29 lacks of the bone volume posterior maxillary region from June 2004 to April 2011, at the Department of Oral and Maxillofacial Surgery, Inha University Hospital. Panoramic views were taken before the surgery, after the surgery, 6 months after the surgery, and at the time of the final follow-up. The influence of the factors on the grafted bone material resorption rate was evaluated according to the patient characteristics (age and gender), graft material, implant installation stage, implant size, implant placement region, local infection, surgical complication, and residual alveolar bone height. Results The bone graft resorption rate of male patients at the final follow-up was significantly higher than the rate of female patients. The single autogenous bone-grafted site was significantly more resorbed than the autogenous bone combined with the Bio-Oss grafted site. The implant installation stage and residual alveolar height showed a significant correlation with the resorption rate of maxillary sinus bone graft material. The success rate and survival rate of the implant were 92.2% and 100%, respectively. Conclusion Maxillary sinus elevation procedure with autogenous bone graft or autogenous bone in combination with Bio-Oss is a predictable treatment method for

  1. Bone marrow transplant - discharge

    MedlinePlus

    Transplant - bone marrow - discharge; Stem cell transplant - discharge; Hematopoietic stem cell transplant - discharge; Reduced intensity; Non-myeloablative transplant - discharge; Mini transplant - discharge; Allogenic bone marrow transplant - ...

  2. Restoring and maintaining bone in osteopenic female rat skeleton: I. Changes in bone mass and structure

    NASA Technical Reports Server (NTRS)

    Tang, L. Y.; Jee, W. S.; Ke, H. Z.; Kimmel, D. B.

    1992-01-01

    This experiment contains the crucial data for the lose, restore, and maintain (LRM) concept, a practical approach for reversing existing osteoporosis. The LRM concept uses anabolic agents to restore bone mass and architecture (+ phase) and then switches to an agent with the established ability to maintain bone mass, to keep the new bone (+/- phase). The purpose of this study was to learn whether switching to an agent known chiefly for its ability to maintain existing bone mass preserves new bone induced by PGE2 in osteopenic, estrogen-depleted rats. The current study had three phases, the bone loss (-), restore (+), and maintain (+/-) phases. We ovariectomized (OX) or sham ovariectomized (sham-OX) 5.5-month-old female rats (- phase). The OX rats were treated 5 months postovariectomy with 1-6 mg PGE2 per kg/day for 75 days to restore lost cancellous bone mass (+ phase), and then PGE2 treatment was stopped and treatment began with 1 or 5 micrograms/kg of risedronate, a bisphosphonate, twice a week for 60 days (+/- phase). During the loss (-) phase, the cancellous bone volume of the proximal tibial metaphysis in the OX rat fell to 19% of initial and 30% of age-matched control levels. During the restore (+) phase, the cancellous bone volume in OX rats doubled. When PGE2 treatment was stopped, however, and no special maintenance efforts were made during the maintain (+/-) phase, the PGE2-induced cancellous bone disappeared. In contrast, the PGE2-induced cancellous bone persisted when the PGE2 treatment was followed by either a 1 or 5 micrograms treatment of risedronate per kg given twice a week for 60 days during the maintain (+/-) phase. The tibial shaft demonstrated very little cortical bone loss during the loss (-) phase in OX rats. The tibial shaft cortical bone fell some 8%. During the restore (+) phase, new cortical bone in OX rats increased by 22%. When PGE2 treatment was stopped and nothing was given during the maintain (+/-) phase, however, all but the PGE2

  3. Prospective Analysis of Secondary Alveolar Bone Grafting in Cleft Lip and Palate Patients

    PubMed Central

    Reddy, M Gokul Chandra; Babu, V Ramesh; Rao, V Eswar; Chaitanya, J Jaya; Allareddy, S; Reddy, C Charan Kumar

    2015-01-01

    Background: To assess the success of the uptake of bone graft in cleft alveolus of the cleft lip and palate patients, quantitatively through computed tomography (CT) scan 6 months postoperative. To assess the successful eruption of permanent lateral incisor or canine in the bone grafted area. Materials and Methods: The children age group of 9-21 years with unilateral cleft lip and palate came to the hospital, needing secondary alveolar bone grafting. A detailed history and clinical examination of the patient was taken. A 3D CT scan was taken and the volume of the cleft was measured pre-operatively. After ambulatory period, 3D CT scan of the alveolar cleft region was taken and volume of the bone grafted was measured and patient was discharged from the hospital. After 6 months, patient was recalled and again 3D CT scan was taken and the volume of remaining bone was measured. Results: The mean volume of the defect pre-operatively is 0.80 cm3 with a standard deviation of 0.36 cm3 with minimum volume of the defect 0.44 cm3 and maximum volume of the defect 1.60 cm3. The mean volume of the bone post-operative immediately after grafting is 1.01 cm3 with a standard deviation of 0.52 cm3 with minimum of bone volume is 0.48 cm3 and maximum of 2.06 cm3. The mean volume of the bone after 6 months after bone grafting is 0.54 cm3 with a standard deviation of 0.33 cm3, minimum bone volume of 0.22 cm3 and maximum bone volume of 1.42 cm3. Conclusion: The CT scan is a valuable radiographic imaging modality to assess and follow the clinical outcome of secondary alveolar bone grafting. PMID:25954076

  4. Inferential Processing among Adequate and Struggling Adolescent Comprehenders and Relations to Reading Comprehension

    PubMed Central

    Barth, Amy E.; Barnes, Marcia; Francis, David J.; Vaughn, Sharon; York, Mary

    2015-01-01

    Separate mixed model analyses of variance (ANOVA) were conducted to examine the effect of textual distance on the accuracy and speed of text consistency judgments among adequate and struggling comprehenders across grades 6–12 (n = 1203). Multiple regressions examined whether accuracy in text consistency judgments uniquely accounted for variance in comprehension. Results suggest that there is considerable growth across the middle and high school years, particularly for adequate comprehenders in those text integration processes that maintain local coherence. Accuracy in text consistency judgments accounted for significant unique variance for passage-level, but not sentence-level comprehension, particularly for adequate comprehenders. PMID:26166946

  5. Evaluating bone quality in patients with chronic kidney disease

    PubMed Central

    Malluche, Hartmut H.; Porter, Daniel S.; Pienkowski, David

    2013-01-01

    Bone of normal quality and quantity can successfully endure physiologically imposed mechanical loads. Chronic kidney disease–mineral and bone disorder (CKD–MBD) adversely affects bone quality through alterations in bone turnover and mineralization, whereas bone quantity is affected through changes in bone volume. Changes in bone quality can be associated with altered bone material, structure, or microdamage, which can result in an elevated rate of fracture in patients with CKD–MBD. Fractures cannot always be explained by reduced bone quantity and, therefore, bone quality should be assessed with a variety of techniques from the macro-organ level to the nanoscale level. In this Review, we demonstrate the importance of evaluating bone from multiple perspectives and hierarchical levels to understand CKD–MBD-related abnormalities in bone quality. Understanding the relationships between variations in material, structure, microdamage, and mechanical properties of bone in patients with CKD–MBD should aid in the development of new modalities to prevent, or treat, these abnormalities. PMID:24100399

  6. Evaluation of trabecular bone patterns on dental radiographic images: influence of cortical bone

    NASA Astrophysics Data System (ADS)

    Amouriq, Yves; Evenou, Pierre; Arlicot, Aurore; Normand, Nicolas; Layrolle, Pierre; Weiss, Pierre; Guédon, Jean-Pierre

    2010-03-01

    For some authors trabecular bone is highly visible in intraoral radiographs. For other authors, the observed intrabony trabecular pattern is a representation of only the endosteal surface of cortical bone, not of intermedullary striae. The purpose of this preliminary study was to investigate the true anatomical structures that are visible in routine dental radiographs and classically denoted trabecular bone. This is a major point for bone texture analysis on radiographs. Computed radiography (CR) images of dog mandible section in molar region were compared with simulations calculated from high-resolution micro-CT volumes. Calculated simulations were obtained using the Mojette Transform. By digitally editing the CT volume, the simulations were separated into trabecular and cortical components into a region of interest. Different images were compared and correlated, some bone micro-architecture parameters calculated. A high correlation was found between computed radiographs and calculated simulations from micro-CT. The Mojette transform was successful to obtain high quality images. Cortical bone did not contribute to change in a major way simulated images. These first results imply that intrabony trabecular pattern observed on radiographs can not only be a representation of the cortical bone endosteal surface and that trabecular bone is highly visible in intraoral radiographs.

  7. Trabecular bone scales allometrically in mammals and birds

    PubMed Central

    Doube, Michael; Kłosowski, Michał M.; Wiktorowicz-Conroy, Alexis M.; Hutchinson, John R.; Shefelbine, Sandra J.

    2011-01-01

    Many bones are supported internally by a latticework of trabeculae. Scaling of whole bone length and diameter has been extensively investigated, but scaling of the trabecular network is not well characterized. We analysed trabecular geometry in the femora of 90 terrestrial mammalian and avian species with body masses ranging from 3 g to 3400 kg. We found that bone volume fraction does not scale substantially with animal size, while trabeculae in larger animals' femora are thicker, further apart and fewer per unit volume than in smaller animals. Finite element modelling indicates that trabecular scaling does not alter the bulk stiffness of trabecular bone, but does alter strain within trabeculae under equal applied loads. Allometry of bone's trabecular tissue may contribute to the skeleton's ability to withstand load, without incurring the physiological or mechanical costs of increasing bone mass. PMID:21389033

  8. Bone demineralization

    NASA Technical Reports Server (NTRS)

    Mack, P. B.; Vose, G. P.; Vogt, F. B.; Lachance, P. A.

    1971-01-01

    Crew members of the Gemini 4, Gemini 5, and Gemini 7 missions were compared regarding skeletal changes in three major anatomic sites with respect to changes in skeletal density during space flight. Bone-mass changes have been found for the command pilot and the pilot of each mission in the conventional os calcis section, in the combined sections covering 60 percent of the os calcis, and in hand phalanges 5-2 and 4-2. Comparison of radiographically determined losses in X-ray absorbence with X-ray absorbence losses in healthy young men subjected to bedrest immobilization for the same length of time showed that losses for the crewmembers exceeded losses for the bedrest subjects in all cases; this was an indication that restriction of body movement did not represent the only factor involved.

  9. [Clinical usefulness of bone turnover markers in the management of osteoporosis].

    PubMed

    Yano, Shozo

    2013-09-01

    Osteoporosis is a state of elevated risk for bone fracture due to depressed bone strength, which is considered to be the sum of bone mineral density and bone quality. Since a measure of bone quality has not been established, bone mineral density and bone turnover markers are the only way to evaluate bone strength. Bone turnover markers are classified into bone formation marker and resorption marker, which are correlated with the bone formation rate and resorption rate, respectively, and bone matrix-related marker. Bone is always metabolized; old tissue is resorbed by acids and proteases derived from osteoclasts, whereas new bone is produced by osteoblasts. Bone formation and resorption rates should be balanced (also called coupled). When the bone resorption rate exceeds the formation rate(uncoupled state), bone volume will be reduced. Thus, we can comprehend bone metabolism by measuring both formation and resorption markers at the same time. Increased fracture risk is recognized by elevated bone resorption markers and undercarboxylated osteocalcin, which reflects vitamin K insufficiency and bone turnover. These values and the time course give us helpful information to choose medicine suitable for the patients and to judge the responsiveness. If the value is extraordinarily high without renal failure, metabolic bone disorder or bone metastatic tumor should be considered. Bone quality may be assessed by measuring bone matrix-related markers such as homocystein and pentosidine. Since recent studies indicate that the bone is a hormone-producing organ, it is possible that glucose metabolism or an unknown mechanism could be assessed in the future. PMID:24369600

  10. Exercise, lifestyle, and your bones

    MedlinePlus

    Osteoporosis - exercise; Low bone density - exercise ... Osteoporosis is a disease that causes bones to become brittle and more likely to fracture (break). With osteoporosis, the bones lose density. Bone density is the amount of bone ...

  11. Polyhydramnios and bone development: an unexplored relationship.

    PubMed

    Sekulić, S R; Ilić, D; Novakov-Mikić, A

    2010-09-01

    Immersion of a humans and Macaca mulatta into a pool with fluid whose specific weight is equal to their specific weight cause bone demineralization. Also, in professional scuba divers, bone mineral density is reduced. Because of water immersion, the apparent weight of scuba divers represents 10% of their actual weight. The aim of this paper was to point out a previously unexplored aspect of fetal bone development in an environment lacking adequate mechanical stress on fetal bone, such as polyhydramnios. In the first part of gestation, the human fetus develops under conditions similar to neutral floating and has an apparent weight which is approximately 5% of its actual weight. During the last trimester of gestation, the fetus overgrows the intrauterine cavity and its apparent body weight is 60-80% of its actual weight. Polyhydramnios represents an excess of amniotic fluid in the uterus during gestation and it can reduce the apparent weight of the fetus to 10-20% of its actual weight. Reduction of the mechanical stress on fetal bone caused by polyhydramnios may significantly affect bone development and ossification during the last trimester of gestation. It is necessary to direct further studies towards examining bone development and mineralization in newborns from gestations complicated by polyhydramnios. A complete lack of data and studies on fetal bone development and bone mineralization in pregnancies complicated by polyhydramnios is not surprising. There is still a misleading opinion that the fetus is in weightlessness condition in the intrauterine environment throughout the second half of gestation regardless of the amount of amniotic fluid. PMID:20347231

  12. A digital model of trabecular bone.

    PubMed

    Engelke, K; Song, S M; Glüer, C C; Genant, H K

    1996-04-01

    A 3D microCT dataset of bovine bone was used to create a digital 3D model simulating trabecular bone. The model serves a dual purpose: It allows for standard quantitative histomorphometric analysis and it approximates the reality e.g. of high resolution CT in vivo datasets of trabecular bone. Thus the model can potentially be used as a reference to develop 2D and 3D structural analysis algorithms applicable in vivo while it simultaneously allows verification of the results of these algorithms by standard histomorphometry. The model can be used as a standard to evaluate the impact of image processing techniques and of restrictions of imaging systems on the quantitative analysis of structural parameters describing a trabecular network. The model can be used for a comparison of 2D and 3D structural analysis methods and for an analysis of decreasing spatial resolution. The effects of segmentation and filtration can be studied separately and grayscale analysis is possible. As examples standard 2D histomorphometry and the analysis of topological parameters like node number and trabecular network length were applied to the model. The influence of spatial resolution was investigated by decreasing the spatial resolution of the digital model. The bone surface area determined by 3D surface triangulation was only 4% smaller than the surface area determined from the traditional 2D bone histomorphometric parameter bone surface/tissue volume (BS/TV) when 2D results were averaged over all slices of the 3D volume. However, BS/TV showed large (10%) variations among slices within the volume. Both histomorphometric and topological parameters were heavily influenced by spatial resolution and image segmentation. Our initial experience with the digital model indicates a need to investigate bone microstructure based on volume data or to average the 2D results of many slices. PMID:8992879

  13. Trabecular bone as a hierarchical material

    NASA Astrophysics Data System (ADS)

    Jasiuk, Iwona

    2004-03-01

    Trabecular bone is studied as a hierarchical material. The analysis includes the experimental characterization of bone's structure, the measurement of its mechanical properties, and the mechanics modeling at several different length scales: nanoscale (under 1 micron, crystal/fiber level), sub-microscale (1-10 microns, single lamella level), microscale (10-500 microns, single trabecula level), and mesoscale (1 mm - 10 cm, trabecular structure, random network of struts or plates). Experiments include the characterization of bone's ultrastructure using SEM (scanning electron microscopy) and TEM (transmission electron microscopy) at nano and sub-microscale levels. In addition, we use the x-ray microtomography, a nondestructive technique, which can provide the three-dimensional details of bone at mesostructural level. Measurements of mechanical properties are done using the MTS machine and nanoindentation apparatus. We use the MTS testing machine to determine constitutive relations of bone at mesoscale and the nanoindentation technique to determine the properties at lower scales. The experimental observations of bone's hierarchical structure are used in the theoretical analysis of bone's mechanical properties. The calculated results are compared with the experimentally measured ones. The material properties are determined at each scale both analytically (using micromechanics theories) and numerically (using a finite element method, a spring network, and beam network approaches). The computational challenges include a complex irregular, random structure at each level, spatial heterogeneity of bone's structure, applicability of separation of scales law, size of the representative volume element, and in general the dependence of properties on specimen size and boundary conditions.

  14. Study to Determine Adequate Margins in Radiotherapy Planning for Esophageal Carcinoma by Detailing Patterns of Recurrence After Definitive Chemoradiotherapy

    SciTech Connect

    Button, Michael R. Morgan, Carys A.; Croydon, Elizabeth S.; Roberts, S. Ashley; Crosby, Thomas D.L.

    2009-03-01

    Purpose: To ascertain the adequacy of radiotherapy (RT) margins by studying the relapse patterns after definitive chemoradiotherapy for carcinoma of the esophagus. Methods and Materials: We performed a retrospective study assessing the first site of disease relapse after definitive chemoradiotherapy that included four 3-weekly cycles of cisplatin and continuous infusion 5-fluorouracil, with conformal RT (50 Gy in 25 fractions) concurrent with Cycles 3 and 4. The RT planning target volume was the endoscopic ultrasonography/computed tomography-defined gross tumor volume with 1.5-cm lateral and 3-cm superoinferior margins. Results: A total of 145 patients were included. Their average age was 65.4 years, 45% had adenocarcinoma, 61% had lower third esophageal tumors, and 75% had Stage III-IVA disease. After RT, of 142 patients, 85 (60%) had evidence of relapse at a median follow-up of 18 months. The relapse was local (within the RT field) in 55; distant (metastatic) in 13, and a combination of local and distant in 14. The local relapse rates were not influenced by tumor stage, lymph node status, or disease length. Three patients developed a relapse in regions adjacent to the RT fields; however, it is unlikely that larger field margins would have been clinically acceptable or effective in these cases. The median overall survival was 15 months. Conclusion: The gross tumor volume-planning target volume margins in this study appeared adequate. Future efforts to improve outcomes using definitive chemoradiotherapy should be directed toward reducing the high rates of in-field and distant relapses.

  15. Reduced Bone Density and Cortical Bone Indices in Female Adiponectin-Knockout Mice.

    PubMed

    Naot, Dorit; Watson, Maureen; Callon, Karen E; Tuari, Donna; Musson, David S; Choi, Ally J; Sreenivasan, Dharshini; Fernandez, Justin; Tu, Pao Ting; Dickinson, Michelle; Gamble, Greg D; Grey, Andrew; Cornish, Jillian

    2016-09-01

    A positive association between fat and bone mass is maintained through a network of signaling molecules. Clinical studies found that the circulating levels of adiponectin, a peptide secreted from adipocytes, are inversely related to visceral fat mass and bone mineral density, and it has been suggested that adiponectin contributes to the coupling between fat and bone. Our study tested the hypothesis that adiponectin affects bone tissue by comparing the bone phenotype of wild-type and adiponectin-knockout (APN-KO) female mice between the ages of 8-37 weeks. Using a longitudinal study design, we determined body composition and bone density using dual energy x-ray absorptiometry. In parallel, groups of animals were killed at different ages and bone properties were analyzed by microcomputed tomography, dynamic histomorphometry, 3-point bending test, nanoindentation, and computational modelling. APN-KO mice had reduced body fat and decreased whole-skeleton bone mineral density. Microcomputed tomography analysis identified reduced cortical area fraction and average cortical thickness in APN-KO mice in all the age groups and reduced trabecular bone volume fraction only in young APN-KO mice. There were no major differences in bone strength and material properties between the 2 groups. Taken together, our results demonstrate a positive effect of adiponectin on bone geometry and density in our mouse model. Assuming adiponectin has similar effects in humans, the low circulating levels of adiponectin associated with increased fat mass are unlikely to contribute to the parallel increase in bone mass. Therefore, adiponectin does not appear to play a role in the coupling between fat and bone tissue. PMID:27384302

  16. Oestrogen receptor positive breast cancer metastasis to bone: inhibition by targeting the bone microenvironment in vivo.

    PubMed

    Holen, I; Walker, M; Nutter, F; Fowles, A; Evans, C A; Eaton, C L; Ottewell, P D

    2016-03-01

    Clinical trials have shown that adjuvant Zoledronic acid (ZOL) reduces the development of bone metastases irrespective of ER status. However, post-menopausal patients show anti-tumour benefit with ZOL whereas pre-menopausal patients do not. Here we have developed in vivo models of spontaneous ER+ve breast cancer metastasis to bone and investigated the effects of ZOL and oestrogen on tumour cell dissemination and growth. ER+ve (MCF7, T47D) or ER-ve (MDA-MB-231) cells were administered by inter-mammary or inter-cardiac injection into female nude mice ± estradiol. Mice were administered saline or 100 μg/kg ZOL weekly. Tumour growth, dissemination of tumour cells in blood, bone and bone turnover were monitored by luciferase imaging, histology, flow cytometry, two-photon microscopy, micro-CT and TRAP/P1NP ELISA. Estradiol induced metastasis of ER+ve cells to bone in 80-100 % of animals whereas bone metastases from ER-ve cells were unaffected. Administration of ZOL had no effect on tumour growth in the fat pad but significantly inhibited dissemination of ER+ve tumour cells to bone and frequency of bone metastasis. Estradiol and ZOL increased bone volume via different mechanisms: Estradiol increased activity of bone forming osteoblasts whereas administration of ZOL to estradiol supplemented mice decreased osteoclast activity and returned osteoblast activity to levels comparable to that of saline treated mice. ER-ve cells require increased osteoclast activity to grow in bone whereas ER+ve cells do not. Zol does not affect ER+ve tumour growth in soft tissue, however, inhibition of bone turnover by ZOL reduced dissemination and growth of ER+ve breast cancer cells in bone. PMID:26585891

  17. Bone scan appearances following biopsy of bone and bone marrow

    SciTech Connect

    McKillop, J.H.; Maharaj, D.; Boyce, B.F.; Fogelman, I.

    1984-10-01

    The influence of sternal marrow aspiration, iliac crest marrow aspiration, and iliac crest bone biopsy on bone scan appearances was examined. Eighteen patients were scanned a mean of 9.9 days after sternal marrow aspiration with a Salah needle. Bone scans obtained in 9 patients a mean of 10 days aftr iliac crest trephine marrow biopsy with a Jamshidi needle showed no abnormality at the biopsy site. In 18 patients with metabolic bone disease who had undergone iliac crest bone biopsy with an 8 mm needle, a scan abnormality due to the biopsy was usually present when the interval between the biopsy and the scan was 5 days to 2 months. Patients who were scanned within 3 days of iliac crest bone biopsy or more than 2 months after biopsy had normal scan appearance at the biopsy site.

  18. Bone tissue engineering: state of the art and future trends.

    PubMed

    Salgado, António J; Coutinho, Olga P; Reis, Rui L

    2004-08-01

    Although several major progresses have been introduced in the field of bone regenerative medicine during the years, current therapies, such as bone grafts, still have many limitations. Moreover, and in spite of the fact that material science technology has resulted in clear improvements in the field of bone substitution medicine, no adequate bone substitute has been developed and hence large bone defects/injuries still represent a major challenge for orthopaedic and reconstructive surgeons. It is in this context that TE has been emerging as a valid approach to the current therapies for bone regeneration/substitution. In contrast to classic biomaterial approach, TE is based on the understanding of tissue formation and regeneration, and aims to induce new functional tissues, rather than just to implant new spare parts. The present review pretends to give an exhaustive overview on all components needed for making bone tissue engineering a successful therapy. It begins by giving the reader a brief background on bone biology, followed by an exhaustive description of all the relevant components on bone TE, going from materials to scaffolds and from cells to tissue engineering strategies, that will lead to "engineered" bone. Scaffolds processed by using a methodology based on extrusion with blowing agents. PMID:15468269

  19. Bone grafts in dentistry

    PubMed Central

    Kumar, Prasanna; Vinitha, Belliappa; Fathima, Ghousia

    2013-01-01

    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. PMID:23946565

  20. Bone Marrow Transplantation

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a ...

  1. Lamellar Spacing in Cuboid Hydroxyapatite Scaffolds Regulates Bone Formation by Human Bone Marrow Stromal Cells

    PubMed Central

    Afghani, Shahrzad; Franco, Jaime; Launey, Max; Marshall, Sally; Marshall, Grayson W.; Nissenson, Robert; Lee, Janice; Tomsia, Antoni P.; Saiz, Eduardo

    2011-01-01

    Background A major goal in bone engineering is the creation of large volume constructs (scaffolds and stem cells) that bear load. The scaffolds must satisfy two competing requirements—they need be sufficiently porous to allow nutrient flow to maintain cell viability, yet sufficiently dense to bear load. We studied the effect of scaffold macroporosity on bone formation and scaffold strength, for bone formed by human bone marrow stromal cells. Methods Rigid cubical hydroxyapatite/tricalcium phosphate scaffolds were produced by robo-casting. The ceramic line thickness was held constant, but the distance between adjacent lines was either 50, 100, 200, 500, or 1000 μm. Cultured human bone marrow stromal cells were combined with the scaffolds in vitro; transplants were placed into the subcutis of immunodeficient mice. Transplants were harvested 9, 18, 23, 38, or 50 weeks later. Bone formation and scaffold strength were analyzed using histology and compression testing. Results Sixty transplants were evaluated. Cortical bone increased with transplant age, and was greatest among 500 μm transplants. In contrast, maximum transplant strength was greatest among 200 μm transplants. Conclusions Lamellar spacing within scaffolds regulates the extent of bone formation; 500 μm yields the most new bone, whereas 200 μm yields the strongest transplants. PMID:21294634

  2. ATF3 controls proliferation of osteoclast precursor and bone remodeling

    PubMed Central

    Fukasawa, Kazuya; Park, Gyujin; Iezaki, Takashi; Horie, Tetsuhiro; Kanayama, Takashi; Ozaki, Kakeru; Onishi, Yuki; Takahata, Yoshifumi; Yoneda, Yukio; Takarada, Takeshi; Kitajima, Shigetaka; Vacher, Jean; Hinoi, Eiichi

    2016-01-01

    Bone homeostasis is maintained by the sophisticated coupled actions of bone-resorbing osteoclasts and bone-forming osteoblasts. Here we identify activating transcription factor 3 (ATF3) as a pivotal transcription factor for the regulation of bone resorption and bone remodeling under a pathological condition through modulating the proliferation of osteoclast precursors. The osteoclast precursor-specific deletion of ATF3 in mice led to the prevention of receptor activator of nuclear factor-κB (RANK) ligand (RANKL)-induced bone resorption and bone loss, although neither bone volume nor osteoclastic parameter were markedly altered in these knockout mice under the physiological condition. RANKL-dependent osteoclastogenesis was impaired in vitro in ATF3-deleted bone marrow macrophages (BMM). Mechanistically, the deficiency of ATF3 impaired the RANKL-induced transient increase in cell proliferation of osteoclast precursors in bone marrow in vivo as well as of BMM in vitro. Moreover, ATF3 regulated cyclin D1 mRNA expression though modulating activator protein-1-dependent transcription in the osteoclast precursor, and the introduction of cyclin D1 significantly rescued the impairment of osteoclastogenesis in ATF3-deleted BMM. Therefore, these findings suggest that ATF3 could have a pivotal role in osteoclastogenesis and bone homeostasis though modulating cell proliferation under pathological conditions, thereby providing a target for bone diseases. PMID:27480204

  3. The New York Adequacy Study: "Determining the Cost of Providing All Children in New York an Adequate Education." Volume 1: Final Report [and] Volume 2: Technical Appendices

    ERIC Educational Resources Information Center

    Chambers, Jay G.; Parrish, Thomas B.; Levin, Jesse D.; Smith, James R.; Guthrie, James W.; Seder, Rich C.; Taylor, Lori

    2004-01-01

    What is the cost of providing all New York public school students a full opportunity to meet the Regents Learning Standards? This report presents the results of a fifteen-month project undertaken jointly by American Institutes for Research (AIR) and Management Analysis and Planning, Inc. (MAP) to answer this question. This is a "costing out"…

  4. Aging bone in men and women: beyond changes in bone mineral density.

    PubMed

    Russo, C R; Lauretani, F; Bandinelli, S; Bartali, B; Di Iorio, A; Volpato, S; Guralnik, J M; Harris, T; Ferrucci, L

    2003-07-01

    Using peripheral quantitative computed tomography (pQCT) we assessed trabecular and cortical bone density, mass and geometric distribution at the tibia level in 512 men and 693 women, age range 20-102 years, randomly selected from the population living in the Chianti area, Tuscany, Italy. Total, trabecular and cortical bone density decreased linearly with age ( p<0.0001 in both sexes), and the slope of age-associated decline was steeper in women than in men. In men, the cortical bone area was similar in different age groups, while in women older than 60 years it was significantly smaller by approximately 1% per year. The total cross-sectional area of the bone became progressively wider with age, but the magnitude of the age-associated increment was significantly higher in men than in women ( p<0.001). The minimum moment of inertia, an index of mechanical resistance to bending, remained stable with age in men, while it was significantly lower in older compared with younger women (0.5% per year). The increase in bone cross-sectional area in aging men may contribute to the maintenance of adequate bone mechanical competence in the face of declining bone density. In women this compensatory mechanism appears to be less efficient and, accordingly, the bone mechanical competence declines with age. The geometric adaptation of increasing cross-sectional bone size is an important component in the assessment of bone mechanical resistance which is completely overlooked, and potentially misinterpreted, by traditional planar densitometry. PMID:12827220

  5. Does running strengthen bone?

    PubMed

    Boudenot, Arnaud; Achiou, Zahra; Portier, Hugues

    2015-12-01

    Bone is a living tissue needing mechanical stress to maintain strength. Traditional endurance exercises offer only modest effects on bone. Walking and running produce low impact but lead to bone fatigue. This article is specifically addressed to therapists and explains the mechanisms involved for the effects of exercise on bone. Intermittent exercise limits bone fatigue, and downhill exercises increase ground impact forces and involve eccentric muscle contractions, which are particularly osteogenic. PMID:26562001

  6. Basic bone radiology

    SciTech Connect

    Griffiths, H.J.

    1987-01-01

    This clinical book surveys the skeletal system as seen through radiological imaging. It emphasizing abnormalities, disease, and trauma, and includes vital information on bones, bone growth, and the cells involved in bone pathology. It covers many bone diseases and injuries which are rarely covered in medical texts, as well as descriptions of radiologic procedures that specifically relate to the skeleton. This edition includes many illustrations, information on MR imaging and CT scanning, and discussions of osteoporosis, dysplasias, and metabolic bone disease.

  7. Abdominal Fat Is Associated With Lower Bone Formation and Inferior Bone Quality in Healthy Premenopausal Women: A Transiliac Bone Biopsy Study

    PubMed Central

    Dempster, David W.; Recker, Robert R.; Lappe, Joan M.; Zhou, Hua; Zwahlen, Alexander; Müller, Ralph; Zhao, Binsheng; Guo, Xiaotao; Lang, Thomas; Saeed, Isra; Liu, X. Sherry; Guo, X. Edward; Cremers, Serge; Rosen, Clifford J.; Stein, Emily M.; Nickolas, Thomas L.; McMahon, Donald J.; Young, Polly; Shane, Elizabeth

    2013-01-01

    Context: The conventional view that obesity is beneficial for bone strength has recently been challenged by studies that link obesity, particularly visceral obesity, to low bone mass and fractures. It is controversial whether effects of obesity on bone are mediated by increased bone resorption or decreased bone formation. Objective: The objective of the study was to evaluate bone microarchitecture and remodeling in healthy premenopausal women of varying weights. Design: We measured bone density and trunk fat by dual-energy x-ray absorptiometry in 40 women and by computed tomography in a subset. Bone microarchitecture, stiffness, remodeling, and marrow fat were assessed in labeled transiliac bone biopsies. Results: Body mass index (BMI) ranged from 20.1 to 39.2 kg/m2. Dual-energy x-ray absorptiometry-trunk fat was directly associated with BMI (r = 0.78, P < .001) and visceral fat by computed tomography (r = 0.79, P < .001). Compared with women in the lowest tertile of trunk fat, those in the highest tertile had inferior bone quality: lower trabecular bone volume (20.4 ± 5.8 vs 29.1 ± 6.1%; P = .001) and stiffness (433 ± 264 vs 782 ± 349 MPa; P = .01) and higher cortical porosity (8.8 ± 3.5 vs 6.3 ± 2.4%; P = .049). Bone formation rate (0.004 ± 0.002 vs 0.011 ± 0.008 mm2/mm · year; P = .006) was 64% lower in the highest tertile. Trunk fat was inversely associated with trabecular bone volume (r = −0.50; P < .01) and bone formation rate (r = −0.50; P < .001). The relationship between trunk fat and bone volume remained significant after controlling for age and BMI. Conclusions: At the tissue level, premenopausal women with more central adiposity had inferior bone quality and stiffness and markedly lower bone formation. Given the rising levels of obesity, these observations require further investigation. PMID:23515452

  8. Automatic quantification of changes in bone in serial MR images of joints.

    PubMed

    Leung, Kelvin K; Holden, Mark; Saeed, Nadeem; Brooks, Keith J; Buckton, Jacky B; Williams, Ann A; Campbell, Simon P; Changani, Kumar; Reid, David G; Zhao, Yong; Wilde, Mike; Rueckert, Daniel; Hajnal, Joseph V; Hill, Derek L G

    2006-12-01

    Recent innovations in drug therapies have made it highly desirable to obtain sensitive biomarkers of disease progression that can be used to quantify the performance of candidate disease modifying drugs. In order to measure potential image-based biomarkers of disease progression in an experimental model of rheumatoid arthritis (RA), we present two different methods to automatically quantify changes in a bone in in-vivo serial magnetic resonance (MR) images from the model. Both methods are based on rigid and nonrigid image registration to perform the analysis. The first method uses segmentation propagation to delineate a bone from the serial MR images giving a global measure of temporal changes in bone volume. The second method uses rigid body registration to determine intensity change within a bone, and then maps these into a reference coordinate system using nonrigid registration. This gives a local measure of temporal changes in bone lesion volume. We detected significant temporal changes in local bone lesion volume in five out of eight identified candidate bone lesion regions, and significant difference in local bone lesion volume between male and female subjects in three out of eight candidate bone lesion regions. But the global bone volume was found to be fluctuating over time. Finally, we compare our findings with histology of the subjects and the manual segmentation of bone lesions. PMID:17167996

  9. Anorexia nervosa and bone.

    PubMed

    Misra, Madhusmita; Klibanski, Anne

    2014-06-01

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

  10. Anorexia Nervosa and Bone

    PubMed Central

    Misra, Madhusmita; Klibanski, Anne

    2014-01-01

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

  11. Trabecular bone structural variation throughout the human lower limb.

    PubMed

    Saers, Jaap P P; Cazorla-Bak, Yasmin; Shaw, Colin N; Stock, Jay T; Ryan, Timothy M

    2016-08-01

    Trabecular bone is responsive to mechanical loading, and thus may be a useful tool for interpreting past behaviour from fossil morphology. However, the ability to meaningfully interpret variation in archaeological and hominin trabecular morphology depends on the extent to which trabecular bone properties are integrated throughout the postcranium or are locally variable in response to joint specific loading. We investigate both of these factors by comparing trabecular bone throughout the lower limb between a group of highly mobile foragers and two groups of sedentary agriculturalists. Trabecular bone structure is quantified in four volumes of interest placed within the proximal and distal joints of the femur and tibia. We determine how trabecular structures correspond to inferred behavioural differences between populations and whether the patterns are consistent throughout the limb. A significant correlation was found between inferred mobility level and trabecular bone structure in all volumes of interest along the lower limb. The greater terrestrial mobility of foragers is associated with higher bone volume fraction, and thicker and fewer trabeculae (lower connectivity density). In all populations, bone volume fraction decreases while anisotropy increases proximodistally throughout the lower limb. This observation mirrors reductions in cortical bone mass resulting from proximodistal limb tapering. The reduction in strength associated with reduced bone volume fraction may be compensated for by the increased anisotropy in the distal tibia. A similar pattern of trabecular structure is found throughout the lower limb in all populations, upon which a signal of terrestrial mobility appears to be superimposed. These results support the validity of using lower limb trabecular bone microstructure to reconstruct terrestrial mobility levels from the archaeological and fossil records. The results further indicate that care should be taken to appreciate variation resulting from

  12. Bone vascularization and bone micro-architecture characterizations according to the μCT resolution

    NASA Astrophysics Data System (ADS)

    Crauste, E.; Autrusseau, F.; Guédon, Jp.; Pilet, P.; Amouriq, Y.; Weiss, P.; Giumelli, B.

    2015-03-01

    Trabecular bone and its micro-architecture are of prime importance for health. Changes of bone micro-architecture are linked to different pathological situations like osteoporosis and begin now to be understood. In a previous paper [12], we started to investigate the relationships between bone and vessels and proposed some indices of characterization for the vessels issued from those used for the bone. Our main objective in this paper is to qualify the classical values used for bone as well as those we proposed for vessels according to different acquisition parameters and for several thresholding methods used to separate bone vessels and background. This study is also based on vessels perfusion by a contrast agent (barium sulfate mixed with gelatin) before euthanasia on rats. Femurs and tibias as well as mandibles were removed after rat's death and were imaged by microCT (Skyscan 1272, Bruker, Belgium) with a resolution ranging from 18 to 3μm. The so obtained images were analyzed with various softwares (NRecon Reconstruction, CtAn, and CtVox from Bruker) in order to calculate bone and vessels micro-architecture parameters (density of bone/blood within the volume), and to know if the results both for bone and vascular micro-architecture are constant along the chosen pixel resolution. The result is clearly negative. We found a very different characterization both for bone and vessels with the 3μm acquisition. Tibia and mandibles bones were also used to show results that can be visually assessed. The largest portions of the vascular tree are orthogonal to the obtained slices of the bone. Therefore, the contrast agent appears as cylinders of various sizes.

  13. Demineralized Bone Matrix Injection in Consolidation Phase Enhances Bone Regeneration in Distraction Osteogenesis via Endochondral Bone Formation

    PubMed Central

    Kim, Ji-Beom; Seo, Sang Gyo; Kim, Eo Jin; Kim, Ji Hye; Yoo, Won Joon; Cho, Tae-Joon; Choi, In Ho

    2015-01-01

    Background Distraction osteogenesis (DO) is a promising tool for bone and tissue regeneration. However, prolonged healing time remains a major problem. Various materials including cells, cytokines, and growth factors have been used in an attempt to enhance bone formation. We examined the effect of percutaneous injection of demineralized bone matrix (DBM) during the consolidation phase on bone regeneration after distraction. Methods The immature rabbit tibial DO model (20 mm length-gain) was used. Twenty-eight animals received DBM 100 mg percutaneously at the end of distraction. Another 22 animals were left without further procedure (control). Plain radiographs were taken every week. Postmortem bone dual-energy X-ray absorptiometry and micro-computed tomography (micro-CT) studies were performed at the third and sixth weeks of the consolidation period and histological analysis was performed. Results The regenerate bone mineral density was higher in the DBM group when compared with that in the saline injection control group at the third week postdistraction. Quantitative analysis using micro-CT revealed larger trabecular bone volume, higher trabecular number, and less trabecular separation in the DBM group than in the saline injection control group. Cross-sectional area and cortical thickness at the sixth week postdistraction, assessed using micro-CT, were greater in the regenerates of the DBM group compared with the control group. Histological evaluation revealed higher trabecular bone volume and trabecular number in the regenerate of the DBM group. New bone formation was apparently enhanced, via endochondral ossification, at the site and in the vicinity of the injected DBM. DBM was absorbed slowly, but it remained until the sixth postoperative week after injection. Conclusions DBM administration into the distraction gap at the end of the distraction period resulted in a significantly greater regenerate bone area, trabecular number, and cortical thickness in the

  14. Bone scaffolds loaded with siRNA-Semaphorin4d for the treatment of osteoporosis related bone defects

    PubMed Central

    Zhang, Yufeng; Wei, Lingfei; Miron, Richard J.; Shi, Bin; Bian, Zhuan

    2016-01-01

    Osteoporosis is a prominent disorder affecting over 200 million people worldwide. Recently, semaphorins have been implicated in the cell-cell communication between osteoclasts and osteoblasts and have been associated with the progression of osteoporosis. Previously, we demonstrated that knockdown of semaphorin4d (Sema4d) using siRNA delivered with a bone-targeting system prevented bone loss in an osteoporotic animal model. Here, we used this bone-specific technology containing siRNA-Sema4d and fabricated a PLLA scaffold capable of enhancing bone repair following fracture. We investigated the ability of the implant to release siRNA-Sema4d into the surrounding tissues over time and to influence new bone formation in a 3 mm femur osteoporotic defect model in ovariectomized rats. Delivery of the bone-targeting system released from PLLA scaffolds began 2 hours post-implantation, peaked at 1 day, and was sustained over a 21 day period. μCT analysis demonstrated a significantly higher bone volume/total volume bone mineral density and number of osteoblasts in the rats that were transplanted with scaffolds loaded with siRNA-Sema4d. These results confirm the specific role of Sema4d in bone remodeling and demonstrate that significant increases in the speed and quality of new bone formation occur when siRNA-Sema4d is delivered via a PLLA scaffold. PMID:27254469

  15. Bone scaffolds loaded with siRNA-Semaphorin4d for the treatment of osteoporosis related bone defects.

    PubMed

    Zhang, Yufeng; Wei, Lingfei; Miron, Richard J; Shi, Bin; Bian, Zhuan

    2016-01-01

    Osteoporosis is a prominent disorder affecting over 200 million people worldwide. Recently, semaphorins have been implicated in the cell-cell communication between osteoclasts and osteoblasts and have been associated with the progression of osteoporosis. Previously, we demonstrated that knockdown of semaphorin4d (Sema4d) using siRNA delivered with a bone-targeting system prevented bone loss in an osteoporotic animal model. Here, we used this bone-specific technology containing siRNA-Sema4d and fabricated a PLLA scaffold capable of enhancing bone repair following fracture. We investigated the ability of the implant to release siRNA-Sema4d into the surrounding tissues over time and to influence new bone formation in a 3 mm femur osteoporotic defect model in ovariectomized rats. Delivery of the bone-targeting system released from PLLA scaffolds began 2 hours post-implantation, peaked at 1 day, and was sustained over a 21 day period. μCT analysis demonstrated a significantly higher bone volume/total volume bone mineral density and number of osteoblasts in the rats that were transplanted with scaffolds loaded with siRNA-Sema4d. These results confirm the specific role of Sema4d in bone remodeling and demonstrate that significant increases in the speed and quality of new bone formation occur when siRNA-Sema4d is delivered via a PLLA scaffold. PMID:27254469

  16. Bone Mass and Bone Quality Are Altered by Hypoactivity in the Chicken

    PubMed Central

    Aguado, Eric; Pascaretti-Grizon, Florence; Goyenvalle, Eric; Audran, Maurice; Chappard, Daniel

    2015-01-01

    Disuse induces a rapid bone loss in adults; sedentarity is now recognized as a risk factor for osteoporosis. Hypoactivity or confinement also decrease bone mass in adults but their effects are largely unknown and only few animal models have been described. We have used 10 chickens of the rapidly growing strain 857K bred in a large enclosure (FREE group); 10 others were confined in small cages with little space to move around (HYPO group). They were sacrificed at 53 days and femurs and tibias were evaluated by texture analysis, dual energy X-ray densitometry, microcomputed tomography (microCT) and histomorphometry. Hypoactivity had no effect on the length and diameter of the bones. Bone mineral density (BMD), microCT (trabecular bone volume and trabecular microarchitecture) and texture analysis were always found significantly reduced in the animals of the HYPO group. BMD was reduced at both femur and tibia diaphysises; BMD of the metaphysis was significantly reduced in the femur but not in the tibia. An increase in osteoid volume and surfaces was noted in the HYPO group. However, there was no alteration of the mineral phase as the osteoid thickness did not differ from control animals. Bone loss was much more pronounced at the lower femur metaphysis than at the upper metaphysis of the tibia. At the tibia, only microarchitectural changes of trabecular bone could be evidenced. The confined chicken represents a new method for the study of hypodynamia since these animals do not have surgical lesions. PMID:25635404

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

    SciTech Connect

    Porter, Daniel S.; Pienkowski, David; Faugere, Marie-Claude; Malluche, Hartmut H.

    2012-01-01

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

  18. The Digital Astronaut Project Computational Bone Remodeling Model (Beta Version) Bone Summit Summary Report

    NASA Technical Reports Server (NTRS)

    Pennline, James; Mulugeta, Lealem

    2013-01-01

    Under the conditions of microgravity, astronauts lose bone mass at a rate of 1% to 2% a month, particularly in the lower extremities such as the proximal femur [1-3]. The most commonly used countermeasure against bone loss in microgravity has been prescribed exercise [4]. However, data has shown that existing exercise countermeasures are not as effective as desired for preventing bone loss in long duration, 4 to 6 months, spaceflight [1,3,5,6]. This spaceflight related bone loss may cause early onset of osteoporosis to place the astronauts at greater risk of fracture later in their lives. Consequently, NASA seeks to have improved understanding of the mechanisms of bone demineralization in microgravity in order to appropriately quantify this risk, and to establish appropriate countermeasures [7]. In this light, NASA's Digital Astronaut Project (DAP) is working with the NASA Bone Discipline Lead to implement well-validated computational models to help predict and assess bone loss during spaceflight, and enhance exercise countermeasure development. More specifically, computational modeling is proposed as a way to augment bone research and exercise countermeasure development to target weight-bearing skeletal sites that are most susceptible to bone loss in microgravity, and thus at higher risk for fracture. Given that hip fractures can be debilitating, the initial model development focused on the femoral neck. Future efforts will focus on including other key load bearing bone sites such as the greater trochanter, lower lumbar, proximal femur and calcaneus. The DAP has currently established an initial model (Beta Version) of bone loss due to skeletal unloading in femoral neck region. The model calculates changes in mineralized volume fraction of bone in this segment and relates it to changes in bone mineral density (vBMD) measured by Quantitative Computed Tomography (QCT). The model is governed by equations describing changes in bone volume fraction (BVF), and rates of

  19. A method for determining adequate resistance form of complete cast crown preparations.

    PubMed

    Weed, R M; Baez, R J

    1984-09-01

    A diagram with various degrees of occlusal convergence, which takes into consideration the length and diameter of complete crown preparations, was designed as a guide to assist the dentist to obtain adequate resistance form. To test the validity of the diagram, five groups of complete cast crown stainless steel dies were prepared (3.5 mm long, occlusal convergence 10, 13, 16, 19, and 22 degrees). Gold copings were cast for each of the 50 preparations. Displacement force was applied to the casting perpendicularly to a simulated 30-degree cuspal incline until the casting was displaced. Castings were deformed at margins except for the 22-degree group. Castings from this group were displaced without deformation, and it was concluded that there was a lack of adequate resistance form as predicted by the diagram. The hypothesis that the diagram could be used to predict adequate or inadequate resistance form was confirmed by this study. PMID:6384470

  20. Bone and muscle atrophy with suspension of the rat

    NASA Technical Reports Server (NTRS)

    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.

  1. Bone Canopies in Pediatric Renal Osteodystrophy

    PubMed Central

    Pereira, Renata C.; Andersen, Thomas L.; Friedman, Peter A.; Tumber, Navdeep; Salusky, Isidro B.; Wesseling-Perry, Katherine

    2016-01-01

    Pediatric renal osteodystrophy (ROD) is characterized by changes in bone turnover, mineralization, and volume that are brought about by alterations in bone resorption and formation. The resorptive and formative surfaces on the cancellous bone are separated from the marrow cavity by canopies consisting of a layer of flat osteoblastic cells. These canopies have been suggested to play a key role in the recruitment of osteoprogenitors during the process of bone remodeling. This study was performed to address the characteristics of the canopies above bone formation and resorption sites and their association with biochemical and bone histomorphometric parameters in 106 pediatric chronic kidney disease (CKD) patients (stage 2–5) across the spectrum of ROD. Canopies in CKD patients often appeared as thickened multilayered canopies, similar to previous reports in patients with primary hyperparathyroidism. This finding contrasts with the thin appearance reported in healthy individuals with normal kidney function. Furthermore, canopies in pediatric CKD patients showed immunoreactivity to the PTH receptor (PTHR1) as well as to the receptor activator of nuclear factor kappa-B ligand (RANKL). The number of surfaces with visible canopy coverage was associated with plasma parathyroid hormone (PTH) levels, bone formation rate, and the extent of remodeling surfaces. Collectively, these data support the conclusion that canopies respond to the elevated PTH levels in CKD and that they possess the molecular machinery necessary to respond to PTH signaling. PMID:27045269

  2. [Effect of calcitonin on regional blood flow in bones, serum levels of IGF-I and osteocalcin, density and weight of bone ash in oophorectomized rats].

    PubMed

    Zák, J; Kapitola, J; Wallischová, J

    2003-01-01

    It is known that in cases of increased bone remodelation rate, i.e. after castration, local bone blood flow is also increased. But in case of adequate hormonal substitution, bone blood flow, similarly as the remodelation rate, return to normal ranges. Until now, there is no knowledge, if other drug can influence enhanced bone blood flow in oophorectomized animals. In this study authors treated oophorectomized female rats with calcitonin and followed bone blood flow, together with biochemical parameters of bone remodelation activity (osteocalcine), IGF-I levels, weight of bone ash and bone density. The female rats were divided in four groups: controls, oophorectomized, with calcitonin and oophorectomized with calcitonin. The bone blood flow was determined by method of body dispersion of radioactive strontium labelled microspheres. The results of this study show, that, in comparison with controls, the bone remodelation rate (documented with increased osteocalcine levels) and radioactive strontium labelled microspheres capture in bone in increased after oophorectomy (p < 0.05). Ash weight and bone density were decreased (p < 0.05). Simultaneously, the blood IGF-I levels were increased (p < 0.05). After oophorectomized animals were treated with calcitonin, all parameters mentioned above headed towards normal ranges in comparison with group of oophorectomized female rats without calcitonin (p < 0.05). Changes of serum IGF-I levels follow changes of microspheres capture in each group of animals. Authors support the hypothesis, that blood levels of IGF-I could influence local bone blood flow. Calcitonin treatment of oophorectomized animals diminishes also decrement of ash weight and bone density. Results of this work show, that similarly as hormonal substitution therapy after oophorectomy, calcitonin also diminishes increased bone blood flow and bone remodelation parameters. The degree of bone blood flow is probably connected with activity of bone remodelling. PMID

  3. Bisphosphonates and bone quality

    PubMed Central

    Pazianas, Michael; van der Geest, Stefan; Miller, Paul

    2014-01-01

    Bisphosphonates (BPs) are bone-avid compounds used as first-line medications for the prevention and treatment of osteoporosis. They are also used in other skeletal pathologies such as Paget's and metastatic bone disease. They effectively reduce osteoclast viability and also activity in the resorptive phase of bone remodelling and help preserve bone micro-architecture, both major determinants of bone strength and ultimately of the susceptibility to fractures. The chemically distinctive structure of each BP used in the clinic determines their unique affinity, distribution/penetration throughout the bone and their individual effects on bone geometry, micro-architecture and composition or what we call ‘bone quality'. BPs have no clinically significant anabolic effects. This review will touch upon some of the components of bone quality that could be affected by the administration of BPs. PMID:24876930

  4. Comparison of four standards for determining adequate water intake of nursing home residents.

    PubMed

    Gaspar, Phyllis M

    2011-01-01

    Adequate hydration for nursing home residents is problematic. The purpose of this study was to compare four standards used to determine a recommended water intake among nursing home residents. Inconsistencies in the amount of water intake recommended based on the standards compared were identified. The standard based on height and weight provides the most individualized recommendation. An individualized recommendation would facilitate goal setting for the care plan of each older person and assist in the prevention of dehydration. It is essential that a cost-effective and clinically feasible approach to determine adequate water intake be determined for this population to prevent the adverse outcomes associated with dehydration. PMID:21469538

  5. Probiotics Protect Mice from Ovariectomy-Induced Cortical Bone Loss

    PubMed Central

    Ohlsson, Claes; Engdahl, Cecilia; Fåk, Frida; Andersson, Annica; Windahl, Sara H.; Farman, Helen H.; Movérare-Skrtic, Sofia; Islander, Ulrika; Sjögren, Klara

    2014-01-01

    The gut microbiota (GM) modulates the hosts metabolism and immune system. Probiotic bacteria are defined as live microorganisms which when administered in adequate amounts confer a health benefit on the host and can alter the composition of the GM. Germ-free mice have increased bone mass associated with reduced bone resorption indicating that the GM also regulates bone mass. Ovariectomy (ovx) results in bone loss associated with altered immune status. The purpose of this study was to determine if probiotic treatment protects mice from ovx-induced bone loss. Mice were treated with either a single Lactobacillus (L) strain, L. paracasei DSM13434 (L. para) or a mixture of three strains, L. paracasei DSM13434, L. plantarum DSM 15312 and DSM 15313 (L. mix) given in the drinking water during 6 weeks, starting two weeks before ovx. Both the L. para and the L. mix treatment protected mice from ovx-induced cortical bone loss and bone resorption. Cortical bone mineral content was higher in both L. para and L. mix treated ovx mice compared to vehicle (veh) treated ovx mice. Serum levels of the resorption marker C-terminal telopeptides and the urinary fractional excretion of calcium were increased by ovx in the veh treated but not in the L. para or the L. mix treated mice. Probiotic treatment reduced the expression of the two inflammatory cytokines, TNFα and IL-1β, and increased the expression of OPG, a potent inhibitor of osteoclastogenesis, in cortical bone of ovx mice. In addition, ovx decreased the frequency of regulatory T cells in bone marrow of veh treated but not probiotic treated mice. In conclusion, treatment with L. para or the L. mix prevents ovx-induced cortical bone loss. Our findings indicate that these probiotic treatments alter the immune status in bone resulting in attenuated bone resorption in ovx mice. PMID:24637895

  6. Cochlear labyrinth volume in Krapina Neandertals.

    PubMed

    Beals, Michaela E; Frayer, David W; Radovčić, Jakov; Hill, Cheryl A

    2016-01-01

    Research with extant primate taxa suggests that cochlear labyrinth volume is functionally related to the range of audible frequencies. Specifically, cochlear volume is negatively correlated with both the high and low frequency limits of hearing so that the smaller the cochlea, the higher the normal range of audible frequencies. The close anatomical relationship between the membranous cochlea and the bony cochlear labyrinth allows for the determination of cochlear size from fossil specimens. This study compares Krapina Neandertal cochlear volumes to extant taxa cochlear volumes. Cochlear volumes were acquired from high-resolution computed tomography scans of temporal bones of Krapina Neandertals, chimpanzees, gorillas, and modern humans. We find that Krapina Neandertals' cochlear volumes are similar to modern Homo sapiens and are significantly larger than chimpanzee and gorilla cochlear volumes. The measured cochlear volume in Krapina Neandertals suggests they had a range of audible frequencies similar to the modern human range. PMID:26603101

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

    PubMed Central

    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

  8. Fracture toughness of steel-fiber-reinforced bone cement.

    PubMed

    Kotha, S P; Li, C; Schmid, S R; Mason, J J

    2004-09-01

    Fractures in the bone-cement mantle (polymethyl methacrylate) have been linked to the failure of cemented total joint prostheses. The heat generated by the curing bone cement has also been implicated in the necrosis of surrounding bone tissue, leading to loosening of the implants. The addition of reinforcements may improve the fracture properties of bone cement and decrease the peak temperatures during curing. This study investigates the changes in the fracture properties and the temperatures generated in the ASTM F451 tests by the addition of 316L stainless steel fibers to bone cement. The influence of filler volume fraction (5-15% by volume) and aspect ratios (19, 46, 57) on the fracture toughness of the acrylic bone cement was assessed. Increasing the volume fraction of the steel fibers resulted in significant increases in the fracture toughness of the steel-fiber-reinforced composite. Fracture-toughness increases of up to 2.63 times the control values were obtained with the use of steel-fiber reinforcements. No clear trend in the fracture toughness was discerned for increasing aspect ratios of the reinforcements. There is a decrease in the peak temperatures reached during the curing of the steel-fiber-reinforced bone cement, though the decrease is too small to be clinically relevant. Large increases in the fatigue life of acrylic bone cement were also obtained by the addition of steel fibers. These results indicate that the use of steel fibers may enhance the durability of cemented joint prostheses. PMID:15293326

  9. Effects of low-intensity pulsed ultrasound on new trabecular bone during bone-tendon junction healing in a rabbit model: a synchrotron radiation micro-CT study.

    PubMed

    Lu, Hongbin; Zheng, Cheng; Wang, Zhanwen; Chen, Can; Chen, Huabin; Hu, Jianzhong

    2015-01-01

    This study was designed to evaluate the effects of low-intensity pulsed ultrasound on bone regeneration during the bone-tendon junction healing process and to explore the application of synchrotron radiation micro computed tomography in three dimensional visualization of the bone-tendon junction to evaluate the microarchitecture of new trabecular bone. Twenty four mature New Zealand rabbits underwent partial patellectomy to establish a bone-tendon junction injury model at the patella-patellar tendon complex. Animals were then divided into low-intensity pulsed ultrasound treatment (20 min/day, 7 times/week) and placebo control groups, and were euthanized at week 8 and 16 postoperatively (n = 6 for each group and time point). The patella-patellar tendon specimens were harvested for radiographic, histological and synchrotron radiation micro computed tomography detection. The area of the newly formed bone in the ultrasound group was significantly greater than that of control group at postoperative week 8 and 16. The high resolution three dimensional visualization images of the bone-tendon junction were acquired by synchrotron radiation micro computed tomography. Low-intensity pulsed ultrasound treatment promoted dense and irregular woven bone formation at week 8 with greater bone volume fraction, number and thickness of new trabecular bone but with lower separation. At week 16, ultrasound group specimens contained mature lamellar bone with higher bone volume fraction and thicker trabeculae than that of control group; however, there was no significant difference in separation and number of the new trabecular bone. This study confirms that low-intensity pulsed ultrasound treatment is able to promote bone formation and remodeling of new trabecular bone during the bone-tendon junction healing process in a rabbit model, and the synchrotron radiation micro computed tomography could be applied for three dimensional visualization to quantitatively evaluate the

  10. New bone formation by murine osteoprogenitor cells cultured on corticocancellous allograft bone.

    PubMed

    Nelson, Ehren R; Huang, Zhinong; Ma, Ting; Lindsey, Derek; Jacobs, Christopher; Smith, Robert L; Goodman, Stuart B

    2008-12-01

    The gold standard for bone grafting in orthopedics is autograft, however autograft has a limited supply and is associated with significant morbidity at the harvest site. One alternative, allograft bone, provides an osteoconductive scaffold, is in less limited supply, and it does not require a harvest from the patient. However, allograft lacks both osteogenic cells and osteoinductive proteins that make autograft bone so advantageous. This study provides a model to investigate strategies for augmentation of corticocancellous allograft bone discs with bone marrow-derived osteoprogenitor cells (OPCs) plus exogenous growth factors in vitro. In this model, allograft bone discs were created by cutting 1-mm thick slices from the distal femur and proximal tibia of euthanized mice. The allografts were sterilized and scanned by micro-computed tomography (microCT) to provide the pre-culture graft volume and trabecular characteristics. The discs were then seeded with OPCs harvested from murine bone marrow. The seeded grafts were placed in organ culture until harvest, after which they were re-scanned by microCT and the data compared to the corresponding pre-culture data. In addition, bone morphogenetic protein-7 (BMP-7, also know as osteogenic protein-1 or OP-1), basic fibroblast growth factor (bFGF), and OP-1 combined with bFGF were added on a daily basis to the cultures. After final microCT scanning, all grafts were sectioned and evaluated histologically after hematoxylin and eosin (H&E) staining. microCT scans of cultured allografts with cells at 3, 5, and 9 weeks showed a time-dependent, statistically significant increase in bone volume. The trabecular thickness (Tb.Th.) of grafts, from both groups that were augmented with OP-1, showed a statistically significant increase in trabecular thickness of allografts with OPCs. These data suggest that bone marrow-derived OPCs adhere to, and produce, new bone on corticocancellous allograft in vitro. When exogenous OP-1 is added to

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

    SciTech Connect

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

    2013-11-15

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

  12. Localized sclerotic bone response demonstrated reduced nanomechanical creep properties.

    PubMed

    Chen, Xiuli; Goh, James Cho Hong; Teoh, Swee Hin; De, Shamal Das; Soong, Richie; Lee, Taeyong

    2013-01-01

    Sclerosis (tissue hardening) development is a common occurrence in slow growing or benign osteolytic lesions. However, there is lack of knowledge on the mechanical and material property changes associated with sclerotic bone response. The immune system is postulated to play a relevant role in evoking sclerotic bone responses. In this study, localized sclerotic response in an immunocompetent model of Walker 256 breast carcinoma in SD rats showed an apparent increase in new reactive bone formation. Sclerotic rat femurs had significant increases in bone mineral density (BMD), bone mineral content (BMC), bone volume fraction (BV/TV), bone surface density (BS/TV), trabecular number (Tb.N) and a significant decrease in trabecular separation (Tb.Sp) and structural model index (SMI) as compared to control rat femurs. Significantly reduced creep responses (increased η) were observed for both trabecular and cortical bone in sclerotic bones while no significant difference was observed in elastic modulus (E) and hardness (H) values. Therefore, we conclude that viscoelastic creep property using nanoindentation would serve as a more sensitive indicator of localized bone modeling than elastic properties. Moreover, reduced viscoelasticity can contribute towards increased microcrack propagation and therefore reduced toughness. Since significant positive correlations between elastic properties (E) and (H) with viscosity (η) were also observed, our results indicate that sclerotic response of bone metastasis would cause reduced toughness (increased η) with stiffening of material (increased E and H). PMID:23127639

  13. [Stereological analysis of rat bone tissue after a flight on the Kosmos-1129 biosatellite].

    PubMed

    Prokhonchukov, A A; Peschanskiĭ, V S

    1982-01-01

    Stereological measurements of volume fractions of 53 samples of compact and spongy structures of bones of 15 rats were carried out. The measurements were performed on cortical lamellae, trabecules and lacunae, channels of osteons and matrices of femoral, tibial and fibular bones of rats. Postflight no significant changes were seen in the above parameters as compared to the vivarium controls. During readaptation to I g a slight increase in the volume fraction of spongy bones was noted. PMID:6750237

  14. Comparison of three calcium phosphate bone graft substitutes from biomechanical, histological, and crystallographic perspectives using a rat posterolateral lumbar fusion model.

    PubMed

    Hu, Ming-Hsien; Lee, Pei-Yuan; Chen, Wen-Cheng; Hu, Jin-Jia

    2014-12-01

    This study evaluated the effectiveness of three calcium phosphate bone graft substitutes with different chemical compositions on spinal fusion using a rat posterolateral lumbar fusion model. Specifically, two recently developed non-dispersive tetracalcium phosphate/dicalcium phosphate anhydrous-based calcium phosphate cements (CPCs), namely a CPC consisting of equimolar amounts of the two compounds (nd-CPC) and a CPC consisting of a two-fold greater amount of dicalcium phosphate anhydrous (DCP-rich CPC), were compared with a commercial calcium phosphate bone graft (c-CPG) consisting of hydroxyapatite (60%) and β-tricalcium phosphate (40%). Single-level posterolateral lumbar fusion was performed at the L4-L5 vertebrae in fifteen adult rats (n=5 for each group). Spinal fusion was evaluated with radiographs, manual palpation, mechanical testing, micro-CT, and histology 8 weeks post-surgery. In particular, the crystallographic phases in the three substitutes were identified before and 8 weeks after their implantation. Manual palpation revealed stable constructs in nearly all of the spine specimens. The stiffness and bending load of fused spines in the two CPC groups were comparable to those in the c-CPG group. The radiographs specifically revealed implant resorption and bone remodeling in the DCP-rich CPC group. Analysis of 3D micro-CT images revealed that the bone volume ratio in the DCP-rich CPC group was significantly greater than those in the nd-CPC and c-CPG groups. Histology showed that the DCP-rich CPC group exhibited the highest degree of bone regeneration and osseointegration. Notably, DCP-rich CPC led to a pronounced phase transformation, generating the greatest amount of poorly crystalline apatite among the three groups, which together with adequate resorption may explain the aforementioned positive findings. We therefore conclude that of the bone graft substitutes considered, DCP-rich CPC has the greatest potential to be used in spinal fusion. PMID

  15. Screw insertion in trabecular bone causes peri-implant bone damage.

    PubMed

    Steiner, Juri A; Ferguson, Stephen J; van Lenthe, G Harry

    2016-04-01

    Secure fracture fixation is still a major challenge in orthopedic surgery, especially in osteoporotic bone. While numerous studies have investigated the effect of implant loading on the peri-implant bone after screw insertion, less focus has been put on bone damage that may occur due to the screw insertion process itself. Therefore, the aim of this study was to localize and quantify peri-implant bone damage caused by screw insertion. We used non-invasive three-dimensional micro-computed tomography to scan twenty human femoral bone cores before and after screw insertion. After image registration of the pre- and post-insertion scans, changes in the bone micro-architecture were identified and quantified. This procedure was performed for screws with a small thread size of 0.3mm (STS, N=10) and large thread size of 0.6mm (LTS, N=10). Most bone damage occurred within a 0.3mm radial distance of the screws. Further bone damage was observed up to 0.6mm and 0.9mm radial distance from the screw, for the STS and LTS groups, respectively. While a similar amount of bone damage was found within a 0.3mm radial distance for the two screw groups, there was significantly more bone damage for the LTS group than the STS group in volumes of interest between 0.3-0.6mm and 0.6-0.9mm. In conclusion, this is the first study to localize and quantify peri-implant bone damage caused by screw insertion based on a non-invasive, three-dimensional, micro-CT imaging technique. We demonstrated that peri-implant bone damage already occurs during screw insertion. This should be taken into consideration to further improve primary implant stability, especially in low quality osteoporotic bone. We believe that this technique could be a promising method to assess more systematically the effect of peri-implant bone damage on primary implant stability. Furthermore, including peri-implant bone damage due to screw insertion into patient-specific in silico models of implant-bone systems could improve the

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

    PubMed Central

    Witkowska, Agata; Alibhai, Aziza; Hughes, Chloe; Price, Jennifer; Klisch, Karl; Sturrock, Craig J.

    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

  17. Use of Supercritical Sterilized Bone Allograft in Two Stage Revision ACL Reconstruction

    PubMed Central

    Roe, Justin; Rutten, Sjoerd; Bonnar, Fiona; Salmon, Lucy; Pinczewski, Leo

    2016-01-01

    Objectives: Revision ACL-reconstruction can be compromised by bone loss as result of tunnel widening or poorly placed tunnels. Two-stage revision ACL consist of initial removal of the old fixation hardware and remaining ACL-graft tissue, followed by bone grafting of the tunnels. After a period of graft incorporation and bone remodeling, an ACL-reconstruction is performed. Our primary aim is to examine the use of supercritical carbon dioxide sterilized bone allograft for tunnel grafting in order to determine the bone quality, graft incorporation and remodeling, by using histology and histomorphometric analysis. Secondarily, we aimed to determine whether the histological findings correlate with the timing of the second stage revision procedure. Methods: Case Series. 12 subjects underwent 2-stage revision ACL reconstruction. Femoral and tibial tunnels were bone grafted with supercritical carbon dioxide sterilized bone allograft (Australian Biotechnologies). Mean time from bone grafting to 2nd stage was 8.8 months (range, 5.6 to 21.3 months). Bone biopsies were taken at the time of the 2nd surgery and decalcified and embedded in paraffin. Sections were hematoxylin and eosin stained for microscopic analysis. Results: The graft material was easily identified by its necrotic appearance with empty osteocytes lacunes within the lamellar trabecular bone. In all tissue samples predominately lamellar host bone apposition was seen on the surface of graft fragments known as creeping substitution. Separate bone graft fragments were bridged by newly formed woven bone. In the histological sections of 2 subjects some small islands of chondral cell differentiation were seen, which may relate to endochondral ossification. Active bone remodeling and resorption through combined osteoclastic and osteoblastic activity was present in 2 subjects (7.0 and 6.3 months post grafting), suggesting more advanced phases of graft incorporation. Mean bone volume was 68% over tissue volume (range 33

  18. The Relationship between Parental Involvement and Adequate Yearly Progress among Urban, Suburban, and Rural Schools

    ERIC Educational Resources Information Center

    Ma, Xin; Shen, Jianping; Krenn, Huilan Y.

    2014-01-01

    Using national data from the 2007-08 School and Staffing Survey, we compared the relationships between parental involvement and school outcomes related to adequate yearly progress (AYP) in urban, suburban, and rural schools. Parent-initiated parental involvement demonstrated significantly positive relationships with both making AYP and staying off…

  19. Influenza 2005-2006: vaccine supplies adequate, but bird flu looms.

    PubMed

    Mossad, Sherif B

    2005-11-01

    Influenza vaccine supplies appear to be adequate for the 2005-2006 season, though delivery has been somewhat delayed. However, in the event of a pandemic of avian flu-considered inevitable by most experts, although no one knows when it will happen-the United States would be woefully unprepared. PMID:16315443

  20. Calculating and Reducing Errors Associated with the Evaluation of Adequate Yearly Progress.

    ERIC Educational Resources Information Center

    Hill, Richard

    In the Spring, 1996, issue of "CRESST Line," E. Baker and R. Linn commented that, in efforts to measure the progress of schools, "the fluctuations due to differences in the students themselves could conceal differences in instructional effects." This is particularly true in the context of the evaluation of adequate yearly progress required by…

  1. How Much and What Kind? Identifying an Adequate Technology Infrastructure for Early Childhood Education. Policy Brief

    ERIC Educational Resources Information Center

    Daugherty, Lindsay; Dossani, Rafiq; Johnson, Erin-Elizabeth; Wright, Cameron

    2014-01-01

    To realize the potential benefits of technology use in early childhood education (ECE), and to ensure that technology can help to address the digital divide, providers, families of young children, and young children themselves must have access to an adequate technology infrastructure. The goals for technology use in ECE that a technology…

  2. Prenatal zinc supplementation of zinc-adequate rats adversely affects immunity in offspring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We previously showed that zinc (Zn) supplementation of Zn-adequate dams induced immunosuppressive effects that persist in the offspring after weaning. We investigated whether the immunosuppressive effects were due to in utero exposure and/or mediated via milk using a cross-fostering design. Pregnant...

  3. 75 FR 5893 - Suspension of Community Eligibility for Failure To Maintain Adequate Floodplain Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-05

    ... FR 51735. Executive Order 13132, Federalism. This rule involves no policies that have ] federalism....C. 4001 et seq., Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR... To Maintain Adequate Floodplain Management Regulations AGENCY: Federal Emergency Management...

  4. 26 CFR 1.467-2 - Rent accrual for section 467 rental agreements without adequate interest.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... provide for a variable rate of interest. For purposes of the adequate interest test under paragraph (b)(1) of this section, if a section 467 rental agreement provides for variable interest, the rental... date as the issue date) for the variable rates called for by the rental agreement. For purposes of...

  5. The Unequal Effect of Adequate Yearly Progress: Evidence from School Visits

    ERIC Educational Resources Information Center

    Brown, Abigail B.; Clift, Jack W.

    2010-01-01

    The authors report insights, based on annual site visits to elementary and middle schools in three states from 2004 to 2006, into the incentive effect of the No Child Left Behind Act's requirement that increasing percentages of students make Adequate Yearly Progress (AYP) in every public school. They develop a framework, drawing on the physics…

  6. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Attending veterinarian and adequate veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian...

  7. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Attending veterinarian and adequate veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian...

  8. Perceptions of Teachers in Their First Year of School Restructuring: Failure to Make Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Moser, Sharon

    2010-01-01

    The 2007-2008 school year marked the first year Florida's Title I schools that did not made Adequate Yearly Progress (AYP) for five consecutive years entered into restructuring as mandated by the "No Child Left Behind Act" of 2001. My study examines the perceptions of teacher entering into their first year of school restructuring due to failure to…

  9. A Model for Touch Technique and Computation of Adequate Cane Length.

    ERIC Educational Resources Information Center

    Plain-Switzer, Karen

    1993-01-01

    This article presents a model for the motion of a long-cane executing the touch technique and presents formulas for the projected length of a cane adequate to protect an individual with blindness against wall-type and pole-type hazards. The paper concludes that the long-cane should reach from the floor to the user's armpit. (JDD)

  10. Towards Defining Adequate Lithium Trials for Individuals with Mental Retardation and Mental Illness.

    ERIC Educational Resources Information Center

    Pary, Robert J.

    1991-01-01

    Use of lithium with mentally retarded individuals with psychiatric conditions and/or behavior disturbances is discussed. The paper describes components of an adequate clinical trial and reviews case studies and double-blind cases. The paper concludes that aggression is the best indicator for lithium use, and reviews treatment parameters and…

  11. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... animal health, behavior, and well-being is conveyed to the attending veterinarian; (4) Guidance to... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Attending veterinarian and adequate veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION...

  12. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... on problems of animal health, behavior, and well-being is conveyed to the attending veterinarian; (4... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND...

  13. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... on problems of animal health, behavior, and well-being is conveyed to the attending veterinarian; (4... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND...

  14. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... on problems of animal health, behavior, and well-being is conveyed to the attending veterinarian; (4... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND...

  15. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... animal health, behavior, and well-being is conveyed to the attending veterinarian; (4) Guidance to... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Attending veterinarian and adequate veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION...

  16. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... on problems of animal health, behavior, and well-being is conveyed to the attending veterinarian; (4... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND...

  17. Special or Not so Special: Special Education Background Experiences of Principals and Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Wilcox, Jennifer E.

    2011-01-01

    This mixed-methods study researched the special education background experience of principals and the effect on students in the subgroup of Students with Disabilities in making Adequate Yearly Progress (AYP). In the state of Ohio, schools and districts are expected to make AYP as a whole and additionally make AYP for each subgroup (various…

  18. Inferential Processing among Adequate and Struggling Adolescent Comprehenders and Relations to Reading Comprehension

    ERIC Educational Resources Information Center

    Barth, Amy E.; Barnes, Marcia; Francis, David; Vaughn, Sharon; York, Mary

    2015-01-01

    Separate mixed model analyses of variance were conducted to examine the effect of textual distance on the accuracy and speed of text consistency judgments among adequate and struggling comprehenders across grades 6-12 (n = 1,203). Multiple regressions examined whether accuracy in text consistency judgments uniquely accounted for variance in…

  19. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... with the State's requirements for availability of services, as set forth in § 438.206. (e) CMS' right... HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS MANAGED CARE Quality Assessment and Performance... 42 Public Health 4 2010-10-01 2010-10-01 false Assurances of adequate capacity and services....

  20. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... requirements: (1) Offers an appropriate range of preventive, primary care, and specialty services that is adequate for the anticipated number of enrollees for the service area. (2) Maintains a network of providers... enrollment in its service area in accordance with the State's standards for access to care under this...

  1. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... requirements: (1) Offers an appropriate range of preventive, primary care, and specialty services that is adequate for the anticipated number of enrollees for the service area. (2) Maintains a network of providers... enrollment in its service area in accordance with the State's standards for access to care under this...

  2. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... requirements: (1) Offers an appropriate range of preventive, primary care, and specialty services that is adequate for the anticipated number of enrollees for the service area. (2) Maintains a network of providers... enrollment in its service area in accordance with the State's standards for access to care under this...

  3. Effect of tranquilizers on animal resistance to the adequate stimuli of the vestibular apparatus

    NASA Technical Reports Server (NTRS)

    Maksimovich, Y. B.; Khinchikashvili, N. V.

    1980-01-01

    The effect of tranquilizers on vestibulospinal reflexes and motor activity was studied in 900 centrifuged albino mice. Actometric studies have shown that the tranquilizers have a group capacity for increasing animal resistance to the action of adequate stimuli to the vestibular apparatus.

  4. 21 CFR 314.126 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... conducting clinical investigations of a drug is to distinguish the effect of a drug from other influences... recognized by the scientific community as the essentials of an adequate and well-controlled clinical... randomization and blinding of patients or investigators, or both. If the intent of the trial is to...

  5. Final 2004 Report on Adequate Yearly Progress in the Montgomery County Public Schools

    ERIC Educational Resources Information Center

    Stevenson, Jose W.

    2005-01-01

    The vast majority of Montgomery County public schools made sufficient progress on state testing and accountability standards in 2004 to comply with the adequate yearly progress (AYP) requirements under the "No Child Left Behind (NCLB) Act of 2001." Information released by the Maryland State Department of Education (MSDE) in October 2004 shows that…

  6. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Adequate financial records, statistical data, and... financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination of costs payable by...

  7. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Adequate financial records, statistical data, and... financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination of costs payable by...

  8. Estimates of Adequate School Spending by State Based on National Average Service Levels.

    ERIC Educational Resources Information Center

    Miner, Jerry

    1983-01-01

    Proposes a method for estimating expenditures per student needed to provide educational adequacy in each state. Illustrates the method using U.S., Arkansas, New York, Texas, and Washington State data, covering instruction, special needs, operations and maintenance, administration, and other costs. Estimates ratios of "adequate" to actual spending…

  9. Leadership Style and Adequate Yearly Progress: A Correlational Study of Effective Principal Leadership

    ERIC Educational Resources Information Center

    Leapley-Portscheller, Claudia Iris

    2008-01-01

    Principals are responsible for leading efforts to reach increasingly higher levels of student academic proficiency in schools associated with adequate yearly progress (AYP) requirements. The purpose of this quantitative, correlational study was to identify the degree to which perceptions of principal transformational, transactional, and…

  10. Percentage of Adults with High Cholesterol Whose LDL Cholesterol Levels Are Adequately Controlled

    MedlinePlus

    ... of Adults with High Cholesterol Whose LDL Cholesterol Levels are Adequately Controlled High cholesterol can double a ... with High Cholesterol that is Controlled by Education Level 8k4c-k22f Download these data » Click on legends ...

  11. 42 CFR 413.24 - Adequate cost data and cost finding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Adequate cost data and cost finding. 413.24 Section 413.24 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PRINCIPLES OF REASONABLE COST REIMBURSEMENT; PAYMENT FOR END-STAGE RENAL DISEASE SERVICES; OPTIONAL PROSPECTIVELY...

  12. Principals' Perceptions of Effective Strategies in Meeting Adequate Yearly Progress in Special Education

    ERIC Educational Resources Information Center

    Meyer, Jadie K.

    2012-01-01

    The purpose of this study was to examine the perceptions of principals who have met Adequate Yearly Progress (AYP) with the special education subgroup. This was a qualitative study, utilizing interviews to answer the research questions. The first three research questions analyzed the areas of assessment, building-level leadership, and curriculum…

  13. Human milk feeding supports adequate growth in infants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite current nutritional strategies, premature infants remain at high risk for extrauterine growth restriction. The use of an exclusive human milk-based diet is associated with decreased incidence of necrotizing enterocolitis (NEC), but concerns exist about infants achieving adequate growth. The ...

  14. 75 FR 74022 - Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-30

    ... November 15, 2010 (75 FR 69648). The corrected text of the recommendation approved by the Board is below... or telephone number (202) 694-7000. Correction: In the Federal Register of November 15, 2010 (75 FR... SAFETY BOARD Safety Analysis Requirements for Defining Adequate Protection for the Public and the...

  15. Evaluating Rural Progress in Mathematics Achievement: Threats to the Validity of "Adequate Yearly Progress"

    ERIC Educational Resources Information Center

    Lee, Jaekyung

    2003-01-01

    This article examines major threats to the validity of Adequate Yearly Progress (AYP) in the context of rural schools. Although rural students and their schools made significant academic progress in the past on national and state assessments, the current goal of AYP turns out to be highly unrealistic for them unless states set far lower…

  16. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Exemptions for pesticides adequately regulated by another Federal agency. 152.20 Section 152.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION...

  17. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Exemptions for pesticides adequately regulated by another Federal agency. 152.20 Section 152.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION...

  18. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Exemptions for pesticides adequately regulated by another Federal agency. 152.20 Section 152.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION...

  19. What Is the Cost of an Adequate Vermont High School Education?

    ERIC Educational Resources Information Center

    Rucker, Frank D.

    2010-01-01

    Access to an adequate education has been widely considered an undeniable right since Chief Justice Warren stated in his landmark decision that "Today, education is perhaps the most important function of state and local governments...it is doubtful that any child may reasonably be expected to succeed in life if he is denied the opportunity of an…

  20. Bone strength: current concepts.

    PubMed

    Turner, Charles H

    2006-04-01

    Bones serve several mechanical functions, including acoustic amplification in the middle ear, shielding vital organs from trauma, and serving as levers for muscles to contract against. Bone is a multiphase material made up of a tough collagenous matrix intermingled with rigid mineral crystals. The mineral gives bone its stiffness. Without sufficient mineralization, bones will plastically deform under load. Collagen provides toughness to bone making it less brittle so that it better resists fracture. Bone adapts to mechanical stresses largely by changing its size and shape, which are major determinants of its resistance to fracture. Tissue is added in regions of high mechanical stress providing an efficient means for improving bone strength. Experiments have shown that small additions of bone mineral density (BMD) (5-8%) caused by mechanical loading can improve bone strength by over 60% and extend bone fatigue life by 100-fold. Consequently, it is clear that bone tissue possesses a mechanosensing apparatus that directs osteogenesis to where it is most needed for improving bone strength. The biological processes involved in bone mechanotransduction are poorly understood and further investigation of the molecular mechanisms involved might uncover drug targets for osteoporosis. Several pathways are emerging from current research, including membrane ion channels, ATP signaling, second messengers, such as prostaglandins and nitric oxide, insulin-like growth factors, and Wnt signaling. PMID:16831941

  1. Bone-specific gene expression patterns and whole bone tissue of female mice are programmed by early life exposure to soy isoflavones and folic acid.

    PubMed

    Kaludjerovic, Jovana; Ward, Wendy E

    2015-10-01

    Female mice exposed to soy isoflavones (ISO) during early postnatal life have improved bone outcomes at adulthood. Since long-lasting effects may be mediated by DNA methylation, we hypothesized that providing supplemental folic acid (FA), a methyl donor, during early life, would enhance the positive effect of ISO to bone health. Bone-specific gene expression patterns were studied to understand potential mechanisms. CD-1 dams (n=36) were randomized to adequate or supplemental levels of FA (2 or 8 mg/kg diet) during pregnancy and lactation, and offspring received corn oil or ISO (7 mg/kg body weight/d) from postnatal day 1 to 10. From weaning, pups were fed an adequate FA diet and were studied to 4 months of age. Female offspring exposed to supplemental FA+ISO had higher bone mineral density (BMD), trabecular connectivity and peak load at the lumbar spine compared to females exposed to adequate FA. Female offspring exposed to adequate FA+ISO or supplemental FA had higher (P<.05) BMD and greater resistance to fracture at the lumbar spine and the femur; higher trabecular connectivity at the lumbar spine; and lower expression of DNA methyltransferase 3a (Dnmt3a) and neuropeptide Y (NPY) in the femur compared to mice exposed to adequate FA. In addition, only mice exposed to adequate FA+ISO had microstructural improvements at the femur neck and higher serum osteoprotegrin (OPG) and insulin growth factor-I (IGF-I). In summary, exposure to supplemental FA did not enhance the positive effect of ISO in bone. However, exposure to adequate FA+ISO or supplemental FA improved bone at least in part by suppressing Dnmt3a and NPY. PMID:26089235

  2. Peptide-induced de novo bone formation after tooth extraction prevents alveolar bone loss in a murine tooth extraction model.

    PubMed

    Arai, Yuki; Aoki, Kazuhiro; Shimizu, Yasuhiro; Tabata, Yasuhiko; Ono, Takashi; Murali, Ramachandran; Mise-Omata, Setsuko; Wakabayashi, Noriyuki

    2016-07-01

    Tooth extraction causes bone resorption of the alveolar bone volume. Although recombinant human bone morphogenetic protein 2 (rhBMP-2) markedly promotes de novo bone formation after tooth extraction, the application of high-dose rhBMP-2 may induce side effects, such as swelling, seroma, and an increased cancer risk. Therefore, reduction of the necessary dose of rhBMP-2 which can still obtain sufficient bone mass is necessary by developing a new osteogenic reagent. Recently, we showed that the systemic administration of OP3-4 peptide, which was originally designed as a bone resorption inhibitor, had osteogenic ability both in vitro and in vivo. This study evaluated the ability of the local application of OP3-4 peptide to promote bone formation in a murine tooth extraction model with a very low-dose of BMP. The mandibular incisor was extracted from 10-week-old C57BL6/J male mice and a gelatin hydrogel containing rhBMP-2 with or without OP3-4 peptide (BMP/OP3-4) was applied to the socket of the incisor. Bone formation inside the socket was examined radiologically and histologically at 21 days after the extraction. The BMP/OP3-4-group showed significant bone formation inside the mandibular extraction socket compared to the gelatin-hydrogel-carrier-control group or rhBMP-2-applied group. The BMP/OP3-4-applied mice showed a lower reduction of alveolar bone and fewer osteoclast numbers, suggesting that the newly formed bone inside the socket may prevent resorption of the cortical bone around the extraction socket. Our data revealed that OP3-4 peptide promotes BMP-mediated bone formation inside the extraction socket of mandibular bone, resulting in preservation from the loss of alveolar bone. PMID:27118173

  3. Bone marrow (stem cell) donation

    MedlinePlus

    Stem cell transplant; Allogeneic-donation ... There are two types of bone marrow donation: Autologous bone marrow transplant is when people donate their own bone marrow. "Auto" means self. Allogenic bone marrow transplant is when another person ...

  4. How Is Bone Cancer Diagnosed?

    MedlinePlus

    ... Topic How is bone cancer staged? How is bone cancer diagnosed? A patient’s symptoms, physical exam, and results ... and other imaging tests. Imaging tests to detect bone cancer X-rays Most bone cancers show up on ...

  5. Bioabsorbable bone plates enabled with local, sustained delivery of alendronate for bone regeneration.

    PubMed

    Hur, Woojune; Park, Min; Lee, Jae Yeon; Kim, Myung Hun; Lee, Seung Ho; Park, Chun Gwon; Kim, Se-Na; Min, Hye Sook; Min, Hye Jeong; Chai, Jin Ho; Lee, Sang Jeong; Kim, Sukwha; Choi, Tae Hyun; Choy, Young Bin

    2016-01-28

    We prepared a bone plate enabled with the local, sustained release of alendronate, which is a drug known to inhibit osteoclast-mediated bone resorption and also expedite the bone-remodeling activity of osteoblasts. For this, we coated a bone plate already in clinical use (PLT-1031, Inion, Finland) with a blend of alendronate and a biocompatible polymer, azidobenzoic acid-modified chitosan (i.e., Az-CH) photo-crosslinked by UV irradiation. As we performed the in vitro drug release study, the drug was released from the coating at an average rate of 4.03μg/day for 63days in a sustained manner. To examine the effect on bone regeneration, the plate was fixed on an 8mm cranial critical size defect in living rats and the newly formed bone volume was quantitatively evaluated by micro-computed tomography (micro-CT) at scheduled times over 8weeks. At week 8, the group implanted with the plate enabled with sustained delivery of alendronate showed a significantly higher volume of newly formed bone (52.78±6.84%) than the groups implanted with the plates without drug (23.6±3.81%) (p<0.05). The plate enabled with alendronate delivery also exhibited good biocompatibility on H&E staining, which was comparable to the Inion plate already in clinical use. Therefore, we suggest that a bone plate enabled with local, sustained delivery of alendronate can be a promising system with the combined functionality of bone fixation and its expedited repair. PMID:26682503

  6. Bone mineral density test

    MedlinePlus

    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 ( ...

  7. Ultrasonic bone densitometer

    NASA Technical Reports Server (NTRS)

    Hoop, J. M.

    1972-01-01

    Human bone density changes can be determined by a device originally developed for in-flight testing of astronauts' bones during extended space missions. Device is comparable in size, weight and power consumption to portable television set.

  8. Bone marrow aspiration

    MedlinePlus

    ... creates suction. A small sample of bone marrow fluid flows into the tube. The needle is removed. Pressure and then a bandage are applied to the skin. The bone marrow fluid is sent to a laboratory and examined under ...

  9. Paget's Disease of Bone

    MedlinePlus

    ... might be responsible. It tends to run in families. Many people do not know they have Paget's disease because their symptoms are mild. For others, symptoms can include Pain Enlarged bones Broken bones Damaged cartilage in joints Doctors use blood ...

  10. What Is Bone?

    MedlinePlus

    ... a soft framework, and calcium phosphate is a mineral that adds strength and hardens the framework. This ... bone formation continues at a faster pace than removal until bone mass peaks during the third decade ...

  11. Bone fracture repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100077.htm Bone fracture repair - series To use the sharing features on ... to slide 4 out of 4 Indications Overview Fractures of the bones are classified in a number ...

  12. Bone Loss in IBD

    MedlinePlus

    ... DENSITY? Although bone seems as hard as a rock, it’s actually living tissue. Throughout your life, old ... available Bone Loss (.pdf) File: 290 KB 733 Third Avenue, Suite 510, New York, NY 10017 | 800- ...

  13. Bone Marrow Diseases

    MedlinePlus

    ... that help with blood clotting. With bone marrow disease, there are problems with the stem cells or ... marrow makes too many white blood cells Other diseases, such as lymphoma, can spread into the bone ...

  14. Adenosine and Bone Metabolism

    PubMed Central

    Mediero, Aránzazu; Cronstein, Bruce N.

    2013-01-01

    Bone is a dynamic organ that undergoes continuous remodeling whilst maintaining a balance between bone formation and resorption. Osteoblasts, which synthesize and mineralize new bone, and osteoclasts, the cells that resorb bone, act in concert to maintain bone homeostasis. In recent years, there has been increasing appreciation of purinergic regulation of bone metabolism. Adenosine, released locally, mediates its physiologic and pharmacologic actions via interactions with G-protein coupled receptors and recent work has indicated that these receptors are involved in the regulation of osteoclast differentiation and function, as well as osteoblast differentiation and bone formation. Moreover, adenosine receptors also regulate chondrocyte and cartilage homeostasis. These recent findings underscore the potential therapeutic importance of adenosine receptors in regulating bone physiology and pathology. PMID:23499155

  15. Histological evaluation of an impacted bone graft substitute composed of a combination of mineralized and demineralized allograft in a sheep vertebral bone defect.

    PubMed

    Fujishiro, Takaaki; Bauer, Thomas W; Kobayashi, Naomi; Kobayashi, Hideo; Sunwoo, Moon Hae; Seim, Howard B; Turner, A Simon

    2007-09-01

    Demineralized bone matrix (DBMs) preparations are a potential alternative or supplement to autogenous bone graft, but many DBMs have not been adequately tested in clinically relevant animal models. The aim of current study was to compare the efficacy of a new bone graft substitute composed of a combination of mineralized and demineralized allograft, along with hyaluronic acid (AFT Bone Void Filler) with several other bone graft materials in a sheep vertebral bone void model. A drilled defect in the sheep vertebral body was filled with either the new DBM preparation, calcium sulfate (OsteoSet), autologous bone graft, or left empty. The sheep were euthanized after 6 or 12 weeks, and the defects were examined by histology and quantitative histomorphometry. The morphometry data were analyzed by one-way analysis of variance with the post hoc Tukey-Kramer test or the Student's t-test. All of the bone defects in the AFT DBM preparation group showed good new bone formation with variable amounts of residual DBM and mineralized bone graft. The DBM preparation group at 12 weeks contained significantly more new bone than the defects treated with calcium sulfate or left empty (respectively, p < 0.05, p < 0.01). There was no significant difference between the DBM and autograft groups. No adverse inflammatory reactions were associated with any of the three graft materials. The AFT preparation of a mixture of mineralized and demineralized allograft appears to be an effective autograft substitute as tested in this sheep vertebral bone void model. PMID:17309059

  16. Eating disorders and bone.

    PubMed

    Tomlinson, Dale; Morgan, Sarah L

    2013-01-01

    Low bone mineral density (BMD) is a frequent and often-overlooked consequence of eating disorders, in particular anorexia nervosa and eating disorders associated with the female athlete triad. The causes of low BMD are multifactorial and include low peak bone mass accrual, accelerated bone resorption, and changes in bone microarchitecture. Early diagnosis and interventions focused on nutritional rehabilitation and weight gain reduce the risk of further BMD deficits and fractures. PMID:24094471

  17. Radionuclide bone imaging

    SciTech Connect

    Bassett, L.W.; Gold, R.H.; Webber, M.M.

    1981-12-01

    Radionuclide bone imaging of the skeleton, now well established as the most important diagnostic procedure in detecting bone metastases, is also a reliable method for the evaluation of the progression or regression of metastatic bone disease. The article concentrates on the technetium-99m agents and the value of these agents in the widespread application of low-dose radioisotope scanning in such bone diseases as metastasis, osteomyelitis, trauma, osteonecrosis, and other abnormal skeletal conditions.

  18. [Bone tissue engineering scaffolds].

    PubMed

    Fang, Liru; Weng, Wenjian; Shen, Ge; Han, Gaorong; Santos, J D; Du, Peiyi

    2003-03-01

    Bone tissue engineering may provide an alternative to the repairs to skeletal defects resulting from disease, trauma or surgery. Scaffold has played an important role in bone tissue engineering, which functions as the architecture for bone in growth. In this paper, the authors gave a brief introduction about the requirement of bone tissue engineering scaffold, the key of the design of scaffolds and the current research on this subject. PMID:12744187

  19. Bone cysts: unicameral and aneurysmal bone cyst.

    PubMed

    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. PMID:25579825

  20. Bone marrow biopsy

    MedlinePlus

    Biopsy - bone marrow ... A bone marrow biopsy may be done in the health care provider's office or in a hospital. The sample may ... This captures a tiny sample, or core, of bone marrow within the needle. The sample and needle are ...

  1. What's a Funny Bone?

    MedlinePlus

    ... Help White House Lunch Recipes What's a Funny Bone? KidsHealth > For Kids > What's a Funny Bone? Print A A A Text Size Have you ... prickly kind of dull pain? That's your funny bone! It doesn't really hurt as much as ...

  2. Bone mineral density test

    MedlinePlus

    BMD test; Bone density test; Bone densitometry; DEXA scan; DXA; Dual-energy x-ray absorptiometry; p-DEXA; Osteoporosis-BMD ... Bone density testing can be done several ways. The most common and accurate way uses a dual-energy x- ...

  3. Calcium and bones

    MedlinePlus

    Bone strength and calcium ... or if your body does not absorb enough calcium, your bones can get weak or will not grow properly. ... injury. As you age, your body still needs calcium to keep your bones dense and strong. Most experts recommend at least ...

  4. Enhanced bone morphogenetic protein-2-induced ectopic and orthotopic bone formation by intermittent parathyroid hormone (1-34) administration.

    PubMed

    Kempen, Diederik H R; Lu, Lichun; Hefferan, Theresa E; Creemers, Laura B; Heijink, Andras; Maran, Avudaiappan; Dhert, Wouter J A; Yaszemski, Michael J

    2010-12-01

    Bone morphogenetic proteins (BMPs) play a central role in local bone regeneration strategies, whereas the anabolic features of parathyroid hormone (PTH) are particularly appealing for the systemic treatment of generalized bone loss. The aim of the current study was to investigate whether local BMP-2-induced bone regeneration could be enhanced by systemic administration of PTH (1-34). Empty or BMP-2-loaded poly(lactic-co glycolic acid)/poly(propylene fumarate)/gelatin composites were implanted subcutaneously and in femoral defects in rats (n = 9). For the orthotopic site, empty defects were also tested. Each of the conditions was investigated in combination with daily administered subcutaneous PTH (1-34) injections in the neck. After 8 weeks of implantation, bone mineral density (BMD) and bone volume were analyzed using microcomputed tomography and histology. Ectopic bone formation and almost complete healing of the femoral defect were only seen in rats that received BMP-2-loaded composites. Additional treatment of the rats with PTH (1-34) resulted in significantly (p < 0.05) enhanced BMD and bone volume in the BMP-2 composites at both implantation sites. Despite its effect on BMD in the humerus and vertebra, PTH (1-34) treatment had no significant effect on BMD and bone volume in the empty femoral defects and the ectopically or orthotopically implanted empty composites. Histological analysis showed that the newly formed bone had a normal woven and trabecular appearance. Overall, this study suggests that intermittent administration of a low PTH dose alone has limited potential to enhance local bone regeneration in a critical-sized defect in rats. However, when combined with local BMP-2-releasing scaffolds, PTH administration significantly enhanced osteogenesis in both ectopic and orthotopic sites. PMID:20666615

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

    NASA Technical Reports Server (NTRS)

    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

  6. Synthetic biodegradable hydrogel delivery of demineralized bone matrix for bone augmentation in a rat model

    PubMed Central

    Kinard, Lucas A.; Dahlin, Rebecca L.; Lam, Johnny; Lu, Steven; Lee, Esther J.; Kasper, F. Kurtis; Mikos, Antonios G.

    2014-01-01

    There exists a strong clinical need for a more capable and robust method to achieve bone augmentation, and a system with fine-tuned delivery of demineralized bone matrix (DBM) has potential to meet that need. As such, the objective of the present study was to investigate a synthetic biodegradable hydrogel for the delivery of DBM for bone augmentation in a rat model. Oligo(poly(ethylene glycol) fumarate) (OPF) constructs were designed and fabricated by varying the content of rat-derived DBM particles (either 1:3, 1:1, or 3:1 DBM:OPF weight ratio on a dry basis) and using two DBM particle size ranges (50–150 or 150–250 μm). The physical properties of the constructs and the bioactivity of the DBM were evaluated. Select formulations (1:1 and 3:1 with 50–150 μm DBM) were evaluated in vivo compared to an empty control to investigate the effect of DBM dose and construct properties on bone augmentation. Overall, 3:1 constructs with higher DBM content achieved the greatest volume of bone augmentation exceeding 1:1 constructs and empty implants by 3-fold and 5-fold, respectively. As such, we have established that a synthetic, biodegradable hydrogel can function as a carrier for DBM, and that the volume of bone augmentation achieved by the constructs correlated directly to DBM dose. PMID:25046637

  7. The bone care nurse project.

    PubMed

    Casentini, Cristiana; Chiaramonti, Giuseppe; Amedei, Antonietta; Cioppi, Federica; Falchetti, Alberto; Masi, Laura; Brandi, Maria Luisa

    2011-01-01

    the relevance of the adherence/compliance to the prescribed therapy. The "Bone Care Nurse" will also provide specific information leaflets aimed at improving lifestyle, compliance and adherence to therapy prescribed by physician. Specifically, this program will cover not only the prevention of fragility fractures in patients with low bone mass but also will provide general information on healthy lifestyles, such as adequate diet and physical activity, helpful to prevent cardiovascular disease, diabetes, obesity. An increase patient's compliance in taking the antiosteoporotic therapy, as also other concomitant medications will be obtainable. The information collected will be stored in an electronic database, subject to statistical analysis and will be informative on both the degree of knowledge of disease by the patient at the first and follow-up meetings of the Bone Care Nurse project. PMID:22461806

  8. Osteoporosis and bone metabolic parameters in dependence upon calcium intake through milk and milk products.

    PubMed

    Stracke, H; Renner, E; Knie, G; Leidig, G; Minne, H; Federlin, K

    1993-09-01

    The bone mineral content of young adults as well as of osteoporotic patients and age-matched controls without bone disease was measured by single-photon absorptiometry. A retrospective nutrition survey was additionally made to study the relationship between bone mineral content and calcium intake in different periods of life. The bone mineral content and bone mineral density of young adults is directly related to the calcium intake through milk and dairy products. The osteoporotics had a significantly lower bone mineral content than the controls. Calcium intake through milk and milk products in childhood and adolescence had been significantly lower in the patients than in the controls, whereas in the later periods of life (20-30 years prior to the study and at the time of the study) there were no significant differences between the calcium intakes of the two groups. It was also found that an adequate intake of calcium protected against increased bone resorption, as evidenced in particular by the reduced levels of serum osteocalcin, a parameter of bone turnover. In conclusion it can be stated that the data support the hypothesis that adequate calcium intake through milk and milk products in childhood and adolescence is a decisive marker for obtaining a maximum bone mass (peak adult bone mass) and for the prevention of osteoporosis. Furthermore, it can be stated that increased calcium intake in the later years may not reduce the accelerated risk of osteoporosis resulting from inadequate calcium intake during childhood and adolescence. PMID:8243426

  9. Prevention of glucocorticoid induced bone changes with beta-ecdysone

    PubMed Central

    Dai, Weiwei; Jiang, Li; Lay, Yu-An Evan; Chen, Haiyan; Jin, Guoqin; Zhang, Hongliang; Kot, Alex; Ritchie, Robert O.; Lane, Nancy E.; Yao, Wei

    2015-01-01

    Beta-ecdysone (βEcd) is a phytoecdysteroid found in the dry roots and seeds of the asteraceae and achyranthes plants, and is reported to increase osteogenesis in vitro. Since glucocorticoid (GCs) excess is associated with a decrease in bone formation, the purpose of this study was to determine if treatment with βEcd could prevent GC-induced osteoporosis. Two-month-old male Swiss-Webster mice (n=8-10/group) were randomized to either placebo or slow release prednisolone pellets (3.3mg/kg/d) and treated with vehicle control or βEcd (0.5mg/kg/d) for 21 days. GC treatment inhibited age-dependent trabecular gain and cortical bone expansion and this was accompanied by a 30-50% lower bone formation rate (BFR) at both the endosteal and periosteal surfaces. Mice treated with only βEcd significantly increased bone formation on endosteal and periosteal bone surfaces, and increased cortical bone mass were their controls to compare to GC alone. Concurrent treatment of βEcd and GC completely prevented the GC-induced reduction in BFR, trabecular bone volume and partially prevented cortical bone loss. In vitro studies determined that βEcd prevented the GC increase in autophagy of the bone marrow stromal cells as well as in whole bone. In summary, βEcd prevented GC induced changes in bone formation, bone cell viability and bone mass. Additional studies are warranted of βEcd for the treatment of GC induced bone loss. PMID:25585248

  10. Oxytocin and bone.

    PubMed

    Colaianni, Graziana; Sun, Li; Zaidi, Mone; Zallone, Alberta

    2014-10-15

    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

  11. Dietary approaches for bone health: lessons from the Framingham Osteoporosis Study

    PubMed Central

    Sahni, Shivani; Mangano, Kelsey M; McLean, Robert R; Hannan, Marian T; Kiel, Douglas P

    2016-01-01

    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 five thousand adult men and women. PMID:26045228

  12. The concept of adequate causation and Max Weber's comparative sociology of religion.

    PubMed

    Buss, A

    1999-06-01

    Max Weber's The Protestant Ethic and the Spirit of Capitalism, studied in isolation, shows mainly an elective affinity or an adequacy on the level of meaning between the Protestant ethic and the 'spirit' of capitalism. Here it is suggested that Weber's subsequent essays on 'The Economic Ethics of World Religions' are the result of his opinion that adequacy on the level of meaning needs and can be verified by causal adequacy. After some introductory remarks, particularly on elective affinity, the paper tries to develop the concept of adequate causation and the related concept of objective possibility on the basis of the work of v. Kries on whom Weber heavily relied. In the second part, this concept is used to show how the study of the economic ethics of India, China, Rome and orthodox Russia can support the thesis that the 'spirit' of capitalism, although it may not have been caused by the Protestant ethic, was perhaps adequately caused by it. PMID:15260028

  13. Volume rendering in the presence of partial volume effects

    NASA Astrophysics Data System (ADS)

    Souza, Andre D. A.; Udupa, Jayaram K.; Saha, Punam K.

    2002-05-01

    In tomographic images, partial volume effects (PVE) cause several artifacts in volume renditions. In x-ray CT, for example, soft-tissue-like pseudo structures appear in bone-to-air and bone-to-fat interfaces. Further, skin, which is identical to soft tissue in terms of CT number, obscures the rendition of the latter. The purpose of this paper is to demonstrate these phenomena and to provide effective solutions that yield significantly improved renditions. Here, we introduce two methods that detect and classify voxels with PVE in x-ray CT. A method is described to automatically peel skin so that PVE-resolved renditions of bone and soft tissue reveal considerably more details. In the first method, the fraction of each tissue material in each voxel v is estimated by taking into account the intensities of the voxels neighboring v. The second method is based on the following postulate (IEEE PAMI, vol. 23 pp. 689- 706, 2001): In any acquired image, voxels with the highest uncertainty occur in the vicinity of object boundaries. The removal of skin is achieved by means of mathematical morphology. Volume renditions have been created before and after applying the methods for several patient CT datasets. A mathematical phantom experiment involving different levels of PVE has been conducted by adding different degrees of noise and blurring. A quantitative evaluation is done utilizing the mathematical phantom and clinical CT data wherein an operator carefully masked out voxels with PVE in the segmented images. All results have demonstrated the enhanced quality of display of bone and soft tissue after applying the proposed methods. The quantitative evaluations indicate that more than 98% of the voxels with PVE are removed by the two methods and the second method performs slightly better than the first. Further, skin peeling vividly reveals fine details in the soft tissue structures.

  14. A novel strategy to overcome resistance in stent placement at lesion site after adequate predilatation.

    PubMed

    Jain, D; Tolg, R; Katus, H A; Richardt, G

    2000-12-01

    Resistance was encountered in passing a 3 x 18 mm stent across a lesion in the proximal left anterior descending coronary artery. Successive changes in stent with repeated balloon dilatations did not succeed. Finally, a 9 mm stent was passed across the lesion and deployed at the site of maximal resistance. The 18 mm stent was then placed through this stent. A novel strategy to overcome resistance in the stent passage through the lesion after an adequate balloon predilatation is reported. PMID:11103034

  15. Myth 19: Is Advanced Placement an Adequate Program for Gifted Students?

    ERIC Educational Resources Information Center

    Gallagher, Shelagh A.

    2009-01-01

    Is it a myth that Advanced Placement (AP) is an adequate program for gifted students? AP is so covered with myths and assumptions that it is hard to get a clear view of the issues. In this article, the author finds the answer about AP by looking at current realties. First, AP is hard for gifted students to avoid. Second, AP never was a program…

  16. Delay of natural bone loss by higher intakes of specific minerals and vitamins.

    PubMed

    Schaafsma, A; de Vries, P J; Saris, W H

    2001-05-01

    For early prevention or inhibition of postmenopausal and age-related bone loss, nutritional interventions might be a first choice. For some vitamins and minerals an important role in bone metabolism is known or suggested. Calcium and vitamin D support bone mineral density and are basic components in most preventive strategies. Magnesium is involved in a number of activities supporting bone strength, preservation, and remodeling. Fluorine and strontium have bone-forming effects. However, high amounts of both elements may reduce bone strength. Boron is especially effective in case of vitamin D, magnesium, and potassium deficiency. Vitamin K is essential for the activation of osteocalcin. Vitamin C is an important stimulus for osteoblast-derived proteins. Increasing the recommended amounts (US RDA 1989), adequate intakes (US DRI 1997), or assumed normal intakes of mentioned food components may lead to a considerable reduction or even prevention of bone loss, especially in late postmenopausal women and the elderly. PMID:11401244

  17. Method for fusing bone

    DOEpatents

    Mourant, Judith R.; Anderson, Gerhard D.; Bigio, Irving J.; Johnson, Tamara M.

    1996-01-01

    Method for fusing bone. The present invention is a method for joining hard tissue which includes chemically removing the mineral matrix from a thin layer of the surfaces to be joined, placing the two bones together, and heating the joint using electromagnetic radiation. The goal of the method is not to produce a full-strength weld of, for example, a cortical bone of the tibia, but rather to produce a weld of sufficient strength to hold the bone halves in registration while either external fixative devices are applied to stabilize the bone segments, or normal healing processes restore full strength to the tibia.

  18. Global risk assessment of aflatoxins in maize and peanuts: are regulatory standards adequately protective?

    PubMed

    Wu, Felicia; Stacy, Shaina L; Kensler, Thomas W

    2013-09-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America. PMID:23761295

  19. Global Risk Assessment of Aflatoxins in Maize and Peanuts: Are Regulatory Standards Adequately Protective?

    PubMed Central

    Wu, Felicia

    2013-01-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America. PMID:23761295

  20. Self-esteem, social support, and satisfaction differences in women with adequate and inadequate prenatal care.

    PubMed

    Higgins, P; Murray, M L; Williams, E M

    1994-03-01

    This descriptive, retrospective study examined levels of self-esteem, social support, and satisfaction with prenatal care in 193 low-risk postpartal women who obtained adequate and inadequate care. The participants were drawn from a regional medical center and university teaching hospital in New Mexico. A demographic questionnaire, the Coopersmith self-esteem inventory, the personal resource questionnaire part 2, and the prenatal care satisfaction inventory were used for data collection. Significant differences were found in the level of education, income, insurance, and ethnicity between women who received adequate prenatal care and those who received inadequate care. Women who were likely to seek either adequate or inadequate prenatal care were those whose total family income was $10,000 to $19,999 per year and high school graduates. Statistically significant differences were found in self-esteem, social support, and satisfaction between the two groups of women. Strategies to enhance self-esteem and social support have to be developed to reach women at risk for receiving inadequate prenatal care. PMID:8155221

  1. Recent progress in injectable bone repair materials research

    NASA Astrophysics Data System (ADS)

    Chen, Zonggang; Zhang, Xiuli; Kang, Lingzhi; Xu, Fei; Wang, Zhaoling; Cui, Fu-Zhai; Guo, Zhongwu

    2015-12-01

    Minimally invasive injectable self-setting materials are useful for bone repairs and for bone tissue regeneration in situ. Due to the potential advantages of these materials, such as causing minimal tissue injury, nearly no influence on blood supply, easy operation and negligible postoperative pain, they have shown great promises and successes in clinical applications. It has been proposed that an ideal injectable bone repair material should have features similar to that of natural bones, in terms of both the microstructure and the composition, so that it not only provides adequate stimulus to facilitate cell adhesion, proliferation and differentiation but also offers a satisfactory biological environment for new bone to grow at the implantation site. This article reviews the properties and applications of injectable bone repair materials, including those that are based on natural and synthetic polymers, calcium phosphate, calcium phosphate/polymer composites and calcium sulfate, to orthopedics and bone tissue repairs, as well as the progress made in biomimetic fabrication of injectable bone repair materials.

  2. Tissue-Engineered Autologous Grafts for Facial Bone Reconstruction

    PubMed Central

    Bhumiratana, Sarindr; Bernhard, Jonathan C.; Alfi, David M.; Yeager, Keith; Eton, Ryan E.; Bova, Jonathan; Shah, Forum; Gimble, Jeffrey M.; Lopez, Mandi J.; Eisig, Sidney B.; Vunjak-Novakovic, Gordana

    2016-01-01

    Facial deformities require precise reconstruction of the appearance and function of the original tissue. The current standard of care—the use of bone harvested from another region in the body—has major limitations, including pain and comorbidities associated with surgery. We have engineered one of the most geometrically complex facial bones by using autologous stromal/stem cells, without bone morphogenic proteins, using native bovine bone matrix and a perfusion bioreactor for the growth and transport of living grafts. The ramus-condyle unit (RCU), the most eminent load-bearing bone in the skull, was reconstructed using an image-guided personalized approach in skeletally mature Yucatan minipigs (human-scale preclinical model). We used clinically approved decellularized bovine trabecular bone as a scaffolding material, and crafted it into an anatomically correct shape using image-guided micromilling, to fit the defect. Autologous adipose-derived stromal/stem cells were seeded into the scaffold and cultured in perfusion for 3 weeks in a specialized bioreactor to form immature bone tissue. Six months after implantation, the engineered grafts maintained their anatomical structure, integrated with native tissues, and generated greater volume of new bone and greater vascular infiltration than either non-seeded anatomical scaffolds or untreated defects. This translational study demonstrates feasibility of facial bone reconstruction using autologous, anatomically shaped, living grafts formed in vitro, and presents a platform for personalized bone tissue engineering. PMID:27306665

  3. Effect of Microstructure on Fatigue Strength of Bovine Compact Bones

    NASA Astrophysics Data System (ADS)

    Kim, Jong Heon; Niinomi, Mitsuo; Akahori, Toshikazu; Takeda, Junji; Toda, Hiroyuki

    Despite its clinical importance in developing artificial bone, limited information is available regarding the microstructure with respect to the fatigue characteristics of bones. In this study, the fatigue characteristics of the bovine humerus and femur were investigated with respect to microstructures. Fatigue tests were conducted on the bovine humerus and femur at a stress ratio of 0.1 and a frequency of 10Hz. The fatigue strength of the plexiform bone is slightly greater than that of the haversian bone. This is because the volume fraction of voids in the haversian bone, which is the site of stress concentration, is higher than that of voids in the plexiform bone. Several microcracks are observed on the fatigue fracture surface of the haversian bone. The microcracks are short and their propagation directions are random. However, the number of the microcracks in the plexiform bone is very small. The microcracks are relatively long and their propagation directions are parallel to the longitudinal direction of the lamellar bone. Therefore, the crack requires relatively more energy to propagate across the lamella in the plexiform bone.

  4. Tissue-engineered autologous grafts for facial bone reconstruction.

    PubMed

    Bhumiratana, Sarindr; Bernhard, Jonathan C; Alfi, David M; Yeager, Keith; Eton, Ryan E; Bova, Jonathan; Shah, Forum; Gimble, Jeffrey M; Lopez, Mandi J; Eisig, Sidney B; Vunjak-Novakovic, Gordana

    2016-06-15

    Facial deformities require precise reconstruction of the appearance and function of the original tissue. The current standard of care-the use of bone harvested from another region in the body-has major limitations, including pain and comorbidities associated with surgery. We have engineered one of the most geometrically complex facial bones by using autologous stromal/stem cells, native bovine bone matrix, and a perfusion bioreactor for the growth and transport of living grafts, without bone morphogenetic proteins. The ramus-condyle unit, the most eminent load-bearing bone in the skull, was reconstructed using an image-guided personalized approach in skeletally mature Yucatán minipigs (human-scale preclinical model). We used clinically approved decellularized bovine trabecular bone as a scaffolding material and crafted it into an anatomically correct shape using image-guided micromilling to fit the defect. Autologous adipose-derived stromal/stem cells were seeded into the scaffold and cultured in perfusion for 3 weeks in a specialized bioreactor to form immature bone tissue. Six months after implantation, the engineered grafts maintained their anatomical structure, integrated with native tissues, and generated greater volume of new bone and greater vascular infiltration than either nonseeded anatomical scaffolds or untreated defects. This translational study demonstrates feasibility of facial bone reconstruction using autologous, anatomically shaped, living grafts formed in vitro, and presents a platform for personalized bone tissue engineering. PMID:27306665

  5. Mandibular Tori: A source of autogenous bone graft

    PubMed Central

    Santhanakrishnan, Muthukumar; Rangarao, Suresh

    2014-01-01

    Restoration of lost alveolar bone support remains as one of the main objectives of periodontal surgery. Amongst the various types of bone grafts available for grafting procedures, autogenous bone grafts are considered to be the gold standard in alveolar defect reconstruction. Although there are various sources for autogenous grafts including the mandibular symphysis and ramus, they are almost invariably not contiguous with the area to be augmented. An alternative mandibular donor site that is continuous with the recipient area and would eliminate the need for an extra surgical site is the tori/exostoses. Bone grafting was planned for this patient as there were angular bone loss present between 35-36 and 36-37. As the volume of bone required was less and bilateral tori were present on the lingual side above the mylohyoid line, the tori was removed and used as a source of autogenous bone graft, which were unnecessary bony extensions present on the mandible and continuous with the recipient area. Post-operative radiographs taken at 6 and 12 month intervals showed good bone fill and also areas of previous pockets, which did not probe after treatment indicates the success of the treatment. The use of mandibular tori as a source of autogenous bone graft should be considered whenever a patient requires bone grafting procedure to be done and presents with a tori. PMID:25624635

  6. Selective laser melting-produced porous titanium scaffolds regenerate bone in critical size cortical bone defects.

    PubMed

    Van der Stok, Johan; Van der Jagt, Olav P; Amin Yavari, Saber; De Haas, Mirthe F P; Waarsing, Jan H; Jahr, Holger; Van Lieshout, Esther M M; Patka, Peter; Verhaar, Jan A N; Zadpoor, Amir A; Weinans, Harrie

    2013-05-01

    Porous titanium scaffolds have good mechanical properties that make them an interesting bone substitute material for large bone defects. These scaffolds can be produced with selective laser melting, which has the advantage of tailoring the structure's architecture. Reducing the strut size reduces the stiffness of the structure and may have a positive effect on bone formation. Two scaffolds with struts of 120-µm (titanium-120) or 230-µm (titanium-230) were studied in a load-bearing critical femoral bone defect in rats. The defect was stabilized with an internal plate and treated with titanium-120, titanium-230, or left empty. In vivo micro-CT scans at 4, 8, and 12 weeks showed more bone in the defects treated with scaffolds. Finally, 18.4 ± 7.1 mm(3) (titanium-120, p = 0.015) and 18.7 ± 8.0 mm(3) (titanium-230, p = 0.012) of bone was formed in those defects, significantly more than in the empty defects (5.8 ± 5.1 mm(3) ). Bending tests on the excised femurs after 12 weeks showed that the fusion strength reached 62% (titanium-120) and 45% (titanium-230) of the intact contralateral femurs, but there was no significant difference between the two scaffolds. This study showed that in addition to adequate mechanical support, porous titanium scaffolds facilitate bone formation, which results in high mechanical integrity of the treated large bone defects. PMID:23255164

  7. Proteomics in bone research.

    PubMed

    Zhang, Hengwei; Recker, Robert; Lee, Wai-Nang Paul; Xiao, Gary Guishan

    2010-02-01

    Osteoporosis is prevalent among the elderly and is a major cause of bone fracture in this population. Bone integrity is maintained by the dynamic processes of bone resorption and bone formation (bone remodeling). Osteoporosis results when there is an imbalance of the two counteracting processes. Bone mineral density, measured by dual-energy x-ray absorptiometry has been the primary method to assess fracture risk for decades. Recent studies demonstrated that measurement of bone turnover markers allows for a dynamic assessment of bone remodeling, while imaging techniques, such as dual-energy x-ray absorptiometry, do not. The application of proteomics has permitted discoveries of new, sensitive, bone turnover markers, which provide unique information for clinical diagnosis and treatment of patients with bone diseases. This review summarizes the recent findings of proteomic studies on bone diseases, properties of mesenchymal stem cells with high expansion rates and osteoblast and osteoclast differentiation, with emphasis on the role of quantitative proteomics in the study of signaling dynamics, biomarkers and discovery of therapeutic targets. PMID:20121480

  8. Ultrasound simulation in bone.

    PubMed

    Kaufman, Jonathan J; Luo, Gangming; Siffert, Robert S

    2008-01-01

    The manner in which ultrasound interacts with bone is of key interest in therapy and diagnosis alike. These may include applications directly to bone, as, for example, in treatment to accelerate the healing of bone fractures and in assessment of bone density in osteoporosis, or indirectly in diagnostic imaging of soft tissue with interest in assessing exposure levels to nearby bone. Because of the lack of analytic solutions to virtually every "practical problem" encountered clinically, ultrasound simulation has become a widely used technique for evaluating ultrasound interactions in bone. This paper provides an overview of the use of ultrasound simulation in bone. A brief description of the mathematical model used to characterize ultrasound propagation in bone is first provided. A number of simulation examples are then presented that explain how simulation may be utilized in a variety of practical configurations. The focus of this paper in terms of examples presented is on diagnostic applications in bone, and, in particular, for assessment of osteoporosis. However, the use of simulation in other areas of interest can easily be extrapolated from the examples presented. In conclusion, this paper describes the use of ultrasound simulation in bone and demonstrates the power of computational methods for ultrasound research in general and tissue and bone applications in particular. PMID:18599409

  9. Surface chemistry and effects on bone regeneration of a novel biomimetic synthetic bone filler.

    PubMed

    Morra, Marco; Giavaresi, Gianluca; Sartori, Maria; Ferrari, Andrea; Parrilli, Annapaola; Bollati, Daniele; Baena, Ruggero Rodriguez Y; Cassinelli, Clara; Fini, Milena

    2015-04-01

    The paper presents results of physico-chemical and biological investigations of a surface-engineered synthetic bone filler. Surface analysis confirms that the ceramic phosphate granules present a collagen nanolayer to the surrounding environment. Cell cultures tests show that, in agreement with literature reports, surface-immobilized collagen molecular cues can stimulate progression along the osteogenic pathway of undifferentiated human mesenchymal cells. Finally, in vivo test in a rabbit model of critical bone defects shows statistically significant increase of bone volume and mineral apposition rate between the biomimetic bone filler and collagen-free control. All together, obtained data confirm that biomolecular surface engineering can upgrade the properties of implant device, by promoting more specific and targeted implant-host cells interactions. PMID:25786396

  10. Skeletal unloading induces selective resistance to the anabolic actions of growth hormone on bone

    NASA Technical Reports Server (NTRS)

    Halloran, B. P.; Bikle, D. D.; Harris, J.; Autry, C. P.; Currier, P. A.; Tanner, S.; Patterson-Buckendahl, P.; Morey-Holton, E.

    1995-01-01

    Loss of skeletal weight bearing or physical unloading of bone in the growing animal inhibits bone formation and induces a bone mineral deficit. To determine whether the inhibition of bone formation induced by skeletal unloading in the growing animal is a consequence of diminished sensitivity to growth hormone (GH) we studied the effects of skeletal unloading in young hypophysectomized rats treated with GH (0, 50, 500 micrograms/100 g body weight/day). Skeletal unloading reduced serum osteocalcin, impaired uptake of 3H-proline into bone, decreased proximal tibial mass, and diminished periosteal bone formation at the tibiofibular junction. When compared with animals receiving excipient alone, GH administration increased bone mass in all animals. The responses in serum osteocalcin, uptake of 3H-proline and 45Ca into the proximal tibia, and proximal tibial mass in non-weight bearing animals were equal to those in weight bearing animals. The responses in trabecular bone volume in the proximal tibia and bone formation at the tibiofibular junction to GH, however, were reduced significantly by skeletal unloading. Bone unloading prevented completely the increase in metaphyseal trabecular bone normally induced by GH and severely dampened the stimulatory effect (158% vs. 313%, p < 0.002) of GH on periosteal bone formation. These results suggest that while GH can stimulate the overall accumulation of bone mineral in both weight bearing and non-weight bearing animals, skeletal unloading selectively impairs the response of trabecular bone and periosteal bone formation to the anabolic actions of GH.

  11. Nanomaterials and bone regeneration

    PubMed Central

    Gong, Tao; Xie, Jing; Liao, Jinfeng; Zhang, Tao; Lin, Shiyu; Lin, Yunfeng

    2015-01-01

    The worldwide incidence of bone disorders and conditions has been increasing. Bone is a nanomaterials composed of organic (mainly collagen) and inorganic (mainly nano-hydroxyapatite) components, with a hierarchical structure ranging from nanoscale to macroscale. In consideration of the serious limitation in traditional therapies, nanomaterials provide some new strategy in bone regeneration. Nanostructured scaffolds provide a closer structural support approximation to native bone architecture for the cells and regulate cell proliferation, differentiation, and migration, which results in the formation of functional tissues. In this article, we focused on reviewing the classification and design of nanostructured materials and nanocarrier materials for bone regeneration, their cell interaction properties, and their application in bone tissue engineering and regeneration. Furthermore, some new challenges about the future research on the application of nanomaterials for bone regeneration are described in the conclusion and perspectives part. PMID:26558141

  12. Marble Bone Disease: A Rare Bone Disorder

    PubMed Central

    Harinathbabu, Maheswari; Thillaigovindan, Ranjani; Prabhu, Geetha

    2015-01-01

    Osteopetrosis, or marble bone disease, is a rare skeletal disorder due to a defective function of the osteoclasts. This defect renders bones more susceptible to osteomyelitis due to decreased vascularity. This disorder is inherited as autosomal dominant and autosomal recessive. Healthcare professionals should urge these patients to maintain their oral health as well as general health, as this condition makes these patients more susceptible to frequent infections and fractures. This case report emphasizes the signs and symptoms of marble bone disease and presents clinical and radiographic findings.  PMID:26594603

  13. Histologic Evaluation of Bone Healing Capacity Following Application of Inorganic Bovine Bone and a New Allograft Material in Rabbit Calvaria

    PubMed Central

    Paknejad, Mojgan; Rokn, AmirReza; Rouzmeh, Nina; Heidari, Mohadeseh; Titidej, Azadehzeinab; Kharazifard, Mohammad Javad; Mehrfard, Ali

    2015-01-01

    Objectives: Considering the importance of bone augmentation prior to implant placement in order to obtain adequate bone quality and quantity, many studies have been conducted to evaluate different techniques and materials regarding new bone formation. In this study, we investigated the bone healing capacity of two different materials deproteinized bovine bone mineral (DBBM with the trade name of Bio-Oss) and demineralized freeze-dried bone allograft (DFDBA with the trade name of DynaGraft). Materials and Methods: This randomized blinded prospective study was conducted on twelve New Zealand white rabbits. Three cranial defects with an equal diameter were created on their calvarium. Subsequently, they were distributed into three groups: 1. The control group without any treatment; 2. The Bio-Oss group; 3. The DynaGraft group. After 30 days, the animals were sacrificed for histologic and histomorphometric analysis. Results: Substantial new bone formation was observed in both groups. DynaGraft: 56/1 % ± 15/1 and Bio-Oss: 53/55 % ± 13/5 compared to the control group: 28/6 % ± 11/2. All groups showed slight inflammation and a small amount of residual biomaterial was observed. Conclusion: Considerable new bone formation was demonstrated in both DynaGraft and Bio-Oss groups in comparison with the control group. Both materials are considered biocompatible regarding the negligible foreign body reaction. PMID:26005452

  14. The Photodynamic Bone Stabilization System: a minimally invasive, percutaneous intramedullary polymeric osteosynthesis for simple and complex long bone fractures

    PubMed Central

    Vegt, Paul; Muir, Jeffrey M; Block, Jon E

    2014-01-01

    The treatment of osteoporotic long bone fractures is difficult due to diminished bone density and compromised biomechanical integrity. The majority of osteoporotic long bone fractures occur in the metaphyseal region, which poses additional problems for surgical repair due to increased intramedullary volume. Treatment with internal fixation using intramedullary nails or plating is associated with poor clinical outcomes in this patient population. Subsequent fractures and complications such as screw pull-out necessitate additional interventions, prolonging recovery and increasing health care costs. The Photodynamic Bone Stabilization System (PBSS) is a minimally invasive surgical technique that allows clinicians to repair bone fractures using a light-curable polymer contained within an inflatable balloon catheter, offering a new treatment option for osteoporotic long bone fractures. The unique polymer compound and catheter application provides a customizable solution for long bone fractures that produces internal stability while maintaining bone length, rotational alignment, and postsurgical mobility. The PBSS has been utilized in a case series of 41 fractures in 33 patients suffering osteoporotic long bone fractures. The initial results indicate that the use of the light-cured polymeric rod for this patient population provides excellent fixation and stability in compromised bone, with a superior complication profile. This paper describes the clinical uses, procedural details, indications for use, and the initial clinical findings of the PBSS. PMID:25540600

  15. The potential role of free chitosan in bone trauma and bone cancer management.

    PubMed

    Tan, Mei L; Shao, Peng; Friedhuber, Anna M; van Moorst, Mallory; Elahy, Mina; Indumathy, Sivanjah; Dunstan, Dave E; Wei, Yongzhong; Dass, Crispin R

    2014-09-01

    Bone defects caused by fractures or cancer-mediated destruction are debilitating. Chitosan is commonly used in scaffold matrices for bone healing, but rarely as a free drug. We demonstrate that free chitosan promotes osteoblast proliferation and osteogenesis in mesenchymal stem cells, increases osteopontin and collagen I expression, and reduces osteoclastogenesis. Chitosan inhibits invasion of endothelial cells, downregulating uPA/R, MT1-MMP, cdc42 and Rac1. Better healing of bone fractures with greater trabecular bone formation was observed in mice treated with chitosan. Chitosan induces apoptosis in osteotropic prostate and breast cancer cells via caspase-2 and -3 activation, and reduces their establishment in bone. Chitosan is pro-apoptotic in osteosarcoma cells, but not their normal counterpart, osteoblasts, or chondrosarcoma cells. Systemic delivery of chitosan does not perturb angiogenesis, bone volume or instinctive behaviour in pregnant mice, but decreases foetal length and changes pancreatic secretory acini. With certain controls in place, chitosan could be useful for bone trauma management. PMID:24947230

  16. Effect of cadmium on bone tissue in growing animals.

    PubMed

    Rodríguez, Juliana; Mandalunis, Patricia Mónica

    2016-08-01

    Accumulation of cadmium (Cd), an extremely toxic metal, can cause renal failure, decreased vitamin D synthesis, and consequently osteoporosis. The aim of this work was to evaluate the effect of Cd on two types of bone in growing Wistar rats. Sixteen 21-day-old male Wistar rats were assigned to one of two groups. The Cd group subcutaneously received 0.5mg/kg of CdCl2 5 times weekly for 3 months. The control group similarly received bidistilled water. Following euthanasia, the mandibles and tibiae were resected, fixed, decalcified and processed histologically to obtain sections for H&E and tartrate-resistant acid phosphatase (TRAP) staining. Photomicrographs were used to determine bone volume (BV/TV%), total growth cartilage width (GPC.Wi) hypertrophic cartilage width (HpZ.Wi), percentage of yellow bone marrow (%YBM), megakaryocyte number (N.Mks/mm(2)), and TRAP+osteoclast number (N.TRAP+Ocl/mm(2)). Results were statistically analyzed using Student's t test. Cd exposed animals showed a significant decrease in subchondral bone volume and a significant increase in TRAP+ osteoclast number and percentage of yellow bone marrow in the tibia, and an increase in megakaryocyte number in mandibular interradicular bone. No significant differences were observed in the remaining parameters. The results obtained with this experimental design show that Cd would seemingly have a different effect on subchondral and interradicular bone. The decrease in bone volume and increase in tibial yellow bone marrow suggest that cadmium inhibits differentiation of mesenchymal cells to osteoblasts, favoring differentiation into adipocytes. The different effects of Cd on interradicular bone might be due to the protective effect of the mastication forces. PMID:27312893

  17. Bone grafts, bone substitutes and orthobiologics

    PubMed Central

    Roberts, Timothy T.; Rosenbaum, Andrew J.

    2012-01-01

    The biology of fracture healing is better understood than ever before, with advancements such as the locking screw leading to more predictable and less eventful osseous healing. However, at times one’s intrinsic biological response, and even concurrent surgical stabilization, is inadequate. In hopes of facilitating osseous union, bone grafts, bone substitutes and orthobiologics are being relied on more than ever before. The osteoinductive, osteoconductive and osteogenic properties of these substrates have been elucidated in the basic science literature and validated in clinical orthopaedic practice. Furthermore, an industry built around these items is more successful and in demand than ever before. This review provides a comprehensive overview of the basic science, clinical utility and economics of bone grafts, bone substitutes and orthobiologics. PMID:23247591

  18. Temporal bone radiography using the orthopantomograph

    SciTech Connect

    Tatezawa, T.

    1981-09-01

    Temporal bone radiographs obtained with an Orthopantomograph were compared with conventional radiographs. In acoustic neurinoma, cholesteatoma, otitis media, and middle fossa tumors, both methods demonstrated the abnormalities well. In two cases with lesions extending beyond the range of conventional projections, the broad orthopantomographic coverage was very valuable. Mastoid air cells, the mastoid process, petrous ridge, and internal auditory meatus were well demonstrated by both techniques. Orthopantomography was found to be superior in the demonstration of the petrous apex, while the superior semicircular canal was better demonstrated on the conventional views. Bilateral symmetry was particularly good and because of fewer films, radiation exposure was considerably less with orthopantomography. For many applications, orthopantomography is an adequate convenient substitute for conventional methods of examining the temporal bones.

  19. Toxicokinetics of bone lead.

    PubMed Central

    Rabinowitz, M B

    1991-01-01

    This article discusses bone as a source of lead to the rest of the body and as a record of past lead exposure. Bone lead levels generally increase with age at rates dependent on the skeletal site and lead exposure. After occupational exposure, the slow decline in blood lead, a 5- to 19-year half-life, reflects the long skeletal half-life. Repeated measurements of bone lead demonstrate the slow elimination of lead from bone. Stable isotope ratios have revealed many details of skeletal uptake and subsequent release. The bulk turnover rates for compact bone are about 2% per year and 8% for spine. Turnover activity varies with age and health. Even though lead approximates calcium, radium, strontium, barium, fluorine, and other bone seekers, the rates for each are different. A simple, two-pool (bone and blood) kinetic model is presented with proposed numerical values for the changes in blood lead levels that occur with changes in turnover rates. Two approaches are offered to further quantify lead turnover. One involves a study of subjects with known past exposure. Changes in the ratio of blood lead to bone lead with time would reflect the course of bone lead availability. Also, stable isotopes and subjects who move from one geographical area to another offer opportunities. Sequential isotope measurements would indicate how much of the lead in blood is from current exposure or bone stores, distinct from changes in absorption or excretion. PMID:2040248

  20. Molecular spectroscopic identification of the water compartments in bone.

    PubMed

    Unal, Mustafa; Yang, Shan; Akkus, Ozan

    2014-10-01

    Matrix bound water is a correlate of bone's fracture resistance and assessment of bound water is emerging as a novel measure of bone's mechanical integrity. Raman spectroscopy is one of the few nondestructive modalities to assess the hydration status in bone; however, it has not been used to study the OH-band in bone. A sequential dehydration protocol was developed to replace unbound (heat drying) and bound (ethanol or deuterium) water in bone. Raman spectra were collected serially to track the OH-band during dehydration. Spectra of synthetic hydroxyapatite, demineralized bone and bulk water were collected to identify mineral and collagen contributions to the OH-band. Band assignments were supported by computational simulations of the molecular vibrations of Gly-Pro-Hyp amino acid sequence. Experimentally and theoretically obtained spectra were interpreted for band-assignments. Water loss was measured gravimetrically and correlated to Raman intensities. Four peaks were identified to be sensitive to dehydration: 3220cm(-1) (water), 3325cm(-1) (NH and water), 3453cm(-1) (hydroxyproline and water), and 3584cm(-1) (mineral and water). These peaks were differentially sensitive to deuterium treatment such that some water peaks were replaced with deuterium oxide faster than the rest. Specifically, the peaks at 3325 and 3584cm(-1) were more tightly bound to the matrix than the remaining bands. Comparison of dehydration in mineralized and demineralized bone revealed a volume of water that may be locked in the matrix by mineral crystals. The OH-range of bone was dominated by collagen and the water since the spectral profile of dehydrated demineralized bone was similar to that of the mineralized bone. Furthermore, water associates to bone mainly by collagen as findings of experimentally and theoretically spectra. The current work is among the first thorough analysis of the Raman OH stretch band in bone and such spectral information may be used to understand the involvement of

  1. High-fat diet enhances and plasminogen activator inhibitor-1 deficiency attenuates bone loss in mice with Lewis Lung carcinoma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study determined the effects of a high-fat diet and plasminogen activator inhibitor-1 deficiency (PAI-1-/-) on bone structure in mice bearing Lewis lung carcinoma (LLC) in lungs. Reduction in bone volume fraction (BV/TV) by 22% and 21%, trabecular number (Tb.N) by 8% and 4% and bone mineral de...

  2. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    PubMed Central

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  3. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt.

    PubMed

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8-10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100-199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  4. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    NASA Astrophysics Data System (ADS)

    de Lange, W. J.

    2014-05-01

    Wim J. de Lange, Geert F. Prinsen, Jacco H. Hoogewoud, Ab A Veldhuizen, Joachim Hunink, Erik F.W. Ruijgh, Timo Kroon Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses

  5. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    NASA Astrophysics Data System (ADS)

    de Lange, Wim; Prinsen, Geert.; Hoogewoud, Jacco; Veldhuizen, Ab; Ruijgh, Erik; Kroon, Timo

    2013-04-01

    Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with? by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses. Regional expertise is welcomed in the calibration phase of NHI. It aims to reduce uncertainties by improving the

  6. Chronic leg ulcer: does a patient always get a correct diagnosis and adequate treatment?

    PubMed

    Mooij, Michael C; Huisman, Laurens C

    2016-03-01

    Patients with chronic leg ulcers have severely impaired quality of life and account for a high percentage of annual healthcare costs. To establish the cause of a chronic leg ulcer, referral to a center with a multidisciplinary team of professionals is often necessary. Treating the underlying cause diminishes healing time and reduces costs. In venous leg ulcers adequate compression therapy is still a problem. It can be improved by training the professionals with pressure measuring devices. A perfect fitting of elastic stockings is important to prevent venous leg ulcer recurrence. In most cases, custom-made stockings are the best choice for this purpose. PMID:26916772

  7. Determining Adequate Margins in Head and Neck Cancers: Practice and Continued Challenges.

    PubMed

    Williams, Michelle D

    2016-09-01

    Margin assessment remains a critical component of oncologic care for head and neck cancer patients. As an integrated team, both surgeons and pathologists work together to assess margins in these complex patients. Differences in method of margin sampling can impact obtainable information and effect outcomes. Additionally, what distance is an "adequate or clear" margin for patient care continues to be debated. Ultimately, future studies and potentially secondary modalities to augment pathologic assessment of margin assessment (i.e., in situ imaging or molecular assessment) may enhance local control in head and neck cancer patients. PMID:27469263

  8. Family Structure Types and Adequate Utilization of Antenatal Care in Kenya.

    PubMed

    Owili, Patrick Opiyo; Muga, Miriam Adoyo; Chou, Yiing-Jenq; Hsu, Yi-Hsin Elsa; Huang, Nicole; Chien, Li-Yin

    2016-01-01

    Features of the health care delivery system may not be the only expounding factors of adequate utilization of antenatal care among women. Other social factors such as the family structure and its environment contribute toward pregnant women's utilization of antenatal care. An understanding of how women in different family structure types and social groups use basic maternal health services is important toward developing and implementing maternal health care policy in the post-Millennium Development Goal era, especially in the sub-Saharan Africa where maternal mortality still remains high. PMID:27214674

  9. Working group on the “adequate minimum” V=volcanic observatory

    USGS Publications Warehouse

    Tilling, R.I.

    1982-01-01

    A working group consisting of R. I. Tilling (United States, Chairman), M. Espendola (Mexico), E. Malavassi (Costa Rica), L. Villari (Italy), and J.P Viode (France) met on the island of Guadeloupe on February 20, 1981, to discuss informally the requirements for a "Minimum" volcano observatory, one which would have the essential monitoring equipment and staff to provide reliable information on the state of an active volcno. Given the premise that any monitoring of a volcano is better than none at all, the owrking group then proceeded to consider the concept of an "adequate minimum" observatory. 

  10. Micro-CT and histologic analyses of bone surrounding immediately loaded miniscrew implants: comparing compression and tension loading.

    PubMed

    Nakagaki, Susumu; Iijima, Masahiro; Handa, Keisuke; Koike, Toshiyuki; Yasuda, Yoshitaka; Saito, Takashi; Mizoguchi, Itaru

    2014-01-01

    This study investigated the effect of immediate force on bone adaptations surrounding miniscrew implants. Ten miniscrew implants were placed on the mandibles in three beagle dogs. Five pairs of miniscrew implants were immediately loaded with 150 g of continuous force using nickel-titanium coil springs for 8 weeks. The values of bone mineral density (BMD), bone mineral content (BMC), and bone volume (BV) of cortical and trabecular bone for compression loading and tension loading were obtained by µCT analysis. The percentages of bone-to-implant contact (BIC) in the compression and tension regions for cortical and trabecular bone were obtained by histologic analysis. The BMD values for the compression region of cortical bone were significantly higher compared to the tension region. The BIC values in cortical and trabecular bone at tension and compression regions were similar. In conclusion, immediate loading does not inhibit osseointegration of miniscrew implants but may stimulate bone mineralization. PMID:24583644

  11. Quantum volume

    NASA Astrophysics Data System (ADS)

    Ryabov, V. A.

    2015-08-01

    Quantum systems in a mechanical embedding, the breathing mode of a small particles, optomechanical system, etc. are far not the full list of examples in which the volume exhibits quantum behavior. Traditional consideration suggests strain in small systems as a result of a collective movement of particles, rather than the dynamics of the volume as an independent variable. The aim of this work is to show that some problem here might be essentially simplified by introducing periodic boundary conditions. At this case, the volume is considered as the independent dynamical variable driven by the internal pressure. For this purpose, the concept of quantum volume based on Schrödinger’s equation in 𝕋3 manifold is proposed. It is used to explore several 1D model systems: An ensemble of free particles under external pressure, quantum manometer and a quantum breathing mode. In particular, the influence of the pressure of free particle on quantum oscillator is determined. It is shown also that correction to the spectrum of the breathing mode due to internal degrees of freedom is determined by the off-diagonal matrix elements of the quantum stress. The new treatment not using the “force” theorem is proposed for the quantum stress tensor. In the general case of flexible quantum 3D dynamics, quantum deformations of different type might be introduced similarly to monopole mode.

  12. Biophotonics and Bone Biology

    NASA Technical Reports Server (NTRS)

    Zimmerli, Gregory; Fischer, David; Asipauskas, Marius; Chauhan, Chirag; Compitello, Nicole; Burke, Jamie; Tate, Melissa Knothe

    2004-01-01

    One of the more-serious side effects of extended space flight is an accelerated bone loss [Bioastronautics Critical Path Roadmap, http://research.hq.nasa.gov/code_u/bcpr/index.cfm]. Rates of bone loss are highest in the weight-bearing bones of the hip and spine regions, and the average rate of bone loss as measured by bone mineral density measurements is around 1.2% per month for persons in a microgravity environment. It shows that an extrapolation of the microgravity induced bone loss rates to longer time scales, such as a 2.5 year round-trip to Mars (6 months out at 0 g, 1.5 year stay on Mars at 0.38 g, 6 months back at 0 g), could severely compromise the skeletal system of such a person.

  13. Biomaterials and bone mechanotransduction

    NASA Technical Reports Server (NTRS)

    Sikavitsas, V. I.; Temenoff, J. S.; Mikos, A. G.; McIntire, L. V. (Principal Investigator)

    2001-01-01

    Bone is an extremely complex tissue that provides many essential functions in the body. Bone tissue engineering holds great promise in providing strategies that will result in complete regeneration of bone and restoration of its function. Currently, such strategies include the transplantation of highly porous scaffolds seeded with cells. Prior to transplantation the seeded cells are cultured in vitro in order for the cells to proliferate, differentiate and generate extracellular matrix. Factors that can affect cellular function include the cell-biomaterial interaction, as well as the biochemical and the mechanical environment. To optimize culture conditions, good understanding of these parameters is necessary. The new developments in bone biology, bone cell mechanotransduction, and cell-surface interactions are reviewed here to demonstrate that bone mechanotransduction is strongly influenced by the biomaterial properties.

  14. Bone loss from high repetitive high force loading is prevented by ibuprofen treatment.

    PubMed

    Jain, N X; Barr-Gillespie, A E; Clark, B D; Kietrys, D M; Wade, C K; Litvin, J; Popoff, S N; Barbe, M F

    2014-03-01

    We examined roles of loading and inflammation on forearm bones in a rat model of upper extremity overuse. Trabecular structure in distal radius and ulna was examined in three groups of young adult rats: 1) 5% food-restricted that underwent an initial training period of 10 min/day for 5 weeks to learn the repetitive task (TRHF); 2) rats that underwent the same training before performing a high repetition high force task, 2 hours/day for 12 weeks (HRHF); and 3) food-restricted only (FRC). Subsets were treated with oral ibuprofen (IBU). TRHF rats had increased trabecular bone volume and numbers, osteoblasts, and serum osteocalcin, indicative of bone adaptation. HRHF rats had constant muscle pulling forces, showed limited signs of bone adaptation, but many signs of bone resorption, including decreased trabecular bone volume and bone mineral density, increased osteoclasts and bone inflammatory cytokines, and reduced median nerve conduction velocity (15%). HRHF+IBU rats showed no trabecular resorptive changes, no increased osteoclasts or bone inflammatory cytokines, no nerve inflammation, preserved nerve conduction, and increased muscle voluntary pulling forces. Ibuprofen treatment preserved trabecular bone quality by reducing osteoclasts and bone inflammatory cytokines, and improving muscle pulling forces on bones as a result of reduced nerve inflammation. PMID:24583543

  15. Effects of Spaceflight on Bone Microarchitecture in the Axial and Appendicular Skeleton in Growing Ovariectomized Rats

    PubMed Central

    Keune, Jessica A.; Branscum, Adam J.; Iwaniec, Urszula T.; Turner, Russell T.

    2015-01-01

    This study investigated the effects of a 14-day spaceflight on bone mass, density and microarchitecture in weight bearing (femur and humerus) and non-weight bearing (2nd lumbar vertebra and calvarium) bones in the context of ovarian hormone insufficiency. 12-week-old Fisher 344 rats were ovariectomized 2 weeks before flight and randomized into one of three groups: 1) baseline (n = 6), 2) ground control (n = 12) or 3) spaceflight (n = 12). Additional ground-based ovary-intact rats provided age-matched reference values at baseline (n = 8) and landing (n = 10). Ovariectomy resulted in bone- and bone compartment-specific deficits in cancellous bone volume fraction. Spaceflight resulted in lower cortical bone accrual in the femur but had no effect on cortical bone in the humerus or calvarium. Cancellous bone volume fraction was lower in flight animals compared to ground control animals in lumbar vertebra and distal femur metaphysis and epiphysis; significant differences were not detected in the distal humerus. Bone loss (compared to baseline controls) in the femur metaphysis was associated with lower trabecular number, whereas trabecular thickness and number were lower in the epiphysis. In summary, the effect of spaceflight on bone microarchitecture in ovariectomized rats was bone-and bone compartment-specific but not strictly related to weight bearing. PMID:26691062

  16. Removal of bone in CT angiography by multiscale matched mask bone elimination

    SciTech Connect

    Gratama van Andel, H. A. F.; Venema, H. W.; Streekstra, G. J.; Straten, M. van; Majoie, C. B. L. M.; Heeten, G. J. den; Grimbergen, C. A.

    2007-10-15

    For clear visualization of vessels in CT angiography (CTA) images of the head and neck using maximum intensity projection (MIP) or volume rendering (VR) bone has to be removed. In the past we presented a fully automatic method to mask the bone [matched mask bone elimination (MMBE)] for this purpose. A drawback is that vessels adjacent to bone may be partly masked as well. We propose a modification, multiscale MMBE, which reduces this problem by using images at two scales: a higher resolution than usual for image processing and a lower resolution to which the processed images are transformed for use in the diagnostic process. A higher in-plane resolution is obtained by the use of a sharper reconstruction kernel. The out-of-plane resolution is improved by deconvolution or by scanning with narrower collimation. The quality of the mask that is used to remove bone is improved by using images at both scales. After masking, the desired resolution for the normal clinical use of the images is obtained by blurring with Gaussian kernels of appropriate widths. Both methods (multiscale and original) were compared in a phantom study and with clinical CTA data sets. With the multiscale approach the width of the strip of soft tissue adjacent to the bone that is masked can be reduced from 1.0 to 0.2 mm without reducing the quality of the bone removal. The clinical examples show that vessels adjacent to bone are less affected and therefore better visible. Images processed with multiscale MMBE have a slightly higher noise level or slightly reduced resolution compared with images processed by the original method and the reconstruction and processing time is also somewhat increased. Nevertheless, multiscale MMBE offers a way to remove bone automatically from CT angiography images without affecting the integrity of the blood vessels. The overall image quality of MIP or VR images is substantially improved relative to images processed with the original MMBE method.

  17. Evaluation metrics for bone segmentation in ultrasound

    NASA Astrophysics Data System (ADS)

    Lougheed, Matthew; Fichtinger, Gabor; Ungi, Tamas

    2015-03-01

    Tracked ultrasound is a safe alternative to X-ray for imaging bones. The interpretation of bony structures is challenging as ultrasound has no specific intensity characteristic of bones. Several image segmentation algorithms have been devised to identify bony structures. We propose an open-source framework that would aid in the development and comparison of such algorithms by quantitatively measuring segmentation performance in the ultrasound images. True-positive and false-negative metrics used in the framework quantify algorithm performance based on correctly segmented bone and correctly segmented boneless regions. Ground-truth for these metrics are defined manually and along with the corresponding automatically segmented image are used for the performance analysis. Manually created ground truth tests were generated to verify the accuracy of the analysis. Further evaluation metrics for determining average performance per slide and standard deviation are considered. The metrics provide a means of evaluating accuracy of frames along the length of a volume. This would aid in assessing the accuracy of the volume itself and the approach to image acquisition (positioning and frequency of frame). The framework was implemented as an open-source module of the 3D Slicer platform. The ground truth tests verified that the framework correctly calculates the implemented metrics. The developed framework provides a convenient way to evaluate bone segmentation algorithms. The implementation fits in a widely used application for segmentation algorithm prototyping. Future algorithm development will benefit by monitoring the effects of adjustments to an algorithm in a standard evaluation framework.

  18. Pulsed Electromagnetic Fields Enhance Bone Morphogenetic Protein-2 Dependent-Bone Regeneration.

    PubMed

    Yang, Hoon Joo; Kim, Ri Youn; Hwang, Soon Jung

    2015-10-01

    The use of recombinant human bone morphogenetic protein-2 (rhBMP-2) for the purpose of promoting bone regeneration is emerging; however, the high dose of rhBMP-2 required in humans is accompanied by several limitations, including bone resorption and swelling. To reduce the dose of rhBMP-2 required, the applicability of pulsed electromagnetic fields (PEMF) was evaluated using a rat calvarial defect model. After creating an 8-mm-diameter calvarial bone defect, a collagen sponge soaked in different concentrations (0, 2.5, 5, 10 μg) of rhBMP-2 was implanted at the defect area. One week after surgery, PEMF was applied for 8 h/day over 5 days in an experimental group of animals (n = 28) using a width of 12 μs, a pulse frequency of 60 Hz, and a magnetic intensity of 10 G. Animals were sacrificed 4 weeks after surgery and assessed by microcomputed tomography and histological and immunohistochemical analyses. In the absence of application of PEMF, bone volume, bone mineral density, trabecular thickness, trabecular number, and trabecular separation, all showed statistically significant differences, depending on the concentration of rhBMP-2 utilized (p < 0.001). PEMF accelerated bone regeneration in the groups that received 0, 2.5, and 5 μg rhBMP-2 (p < 0.05). In contrast, administration of 10 μg rhBMP-2 resulted in no additive effect on bone regeneration in combination with PEMF. Groups receiving no rhBMP-2 showed distinct bone regeneration in the central zone of the bone defect when treated with PEMF, whereas they failed to bridge the defect space without PEMF. Among the groups without PEMF, soft tissue infiltrations from the outer surface on the skin side were common. Among groups with PEMF, the groups receiving 5 and 10 μg rhBMP-2 displayed denser bone with significantly reduced dead spaces. The application of PEMF did not result in an accelerated effect on bone regeneration in groups treated with 10 μg rhBMP-2. Therefore, our data

  19. Pelvic aneurysmal bone cyst

    PubMed Central

    Sharifah, MIA; Nor Hazla, MH; Suraya, A; Tan, SP

    2011-01-01

    This paper describes an extremely rare case of a huge aneurysmal bone cyst (ABC) in the pelvis, occurring in the patient’s 5th decade of life. The patient presented with a history of painless huge pelvic mass for 10 years. Plain radiograph and computed tomography showed huge expansile lytic lesion arising from the right iliac bone. A biopsy was performed and histology confirmed diagnosis of aneurysmal bone cyst. Unfortunately, the patient succumbed to profuse bleeding from the tumour. PMID:22279501

  20. Nanocomposites and bone regeneration

    NASA Astrophysics Data System (ADS)

    James, Roshan; Deng, Meng; Laurencin, Cato T.; Kumbar, Sangamesh G.

    2011-12-01

    This manuscript focuses on bone repair/regeneration using tissue engineering strategies, and highlights nanobiotechnology developments leading to novel nanocomposite systems. About 6.5 million fractures occur annually in USA, and about 550,000 of these individual cases required the application of a bone graft. Autogenous and allogenous bone have been most widely used for bone graft based therapies; however, there are significant problems such as donor shortage and risk of infection. Alternatives using synthetic and natural biomaterials have been developed, and some are commercially available for clinical applications requiring bone grafts. However, it remains a great challenge to design an ideal synthetic graft that very closely mimics the bone tissue structurally, and can modulate the desired function in osteoblast and progenitor cell populations. Nanobiomaterials, specifically nanocomposites composed of hydroxyapatite (HA) and/or collagen are extremely promising graft substitutes. The biocomposites can be fabricated to mimic the material composition of native bone tissue, and additionally, when using nano-HA (reduced grain size), one mimics the structural arrangement of native bone. A good understanding of bone biology and structure is critical to development of bone mimicking graft substitutes. HA and collagen exhibit excellent osteoconductive properties which can further modulate the regenerative/healing process following fracture injury. Combining with other polymeric biomaterials will reinforce the mechanical properties thus making the novel nano-HA based composites comparable to human bone. We report on recent studies using nanocomposites that have been fabricated as particles and nanofibers for regeneration of segmental bone defects. The research in nanocomposites, highlight a pivotal role in the future development of an ideal orthopaedic implant device, however further significant advancements are necessary to achieve clinical use.