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1

Histopathological perspective on bone marrow oedema, reactive bone change and haemorrhage  

International Nuclear Information System (INIS)

This article presents a systematic review of the current biomedical literature surrounding the aetiopathogenesis and histopathological features of bone marrow oedema, reactive bone change and haemorrhage. Bone marrow oedema is generally demonstrated as a non-specific finding on magnetic resonance imaging in association with infections, tumours and avascular necrosis. When it occurs in isolation as a primary event not triggered by any obvious bony pathology in the clinical setting of debilitating joint pain, it constitutes the 'bone marrow oedema syndrome'. Although the latter diagnosis is based on magnetic resonance (MR) imaging, showing the lesion as areas of signal hyperintensity within the marrow, recent radiology-histology correlational studies have shown variably interstitial marrow oedema, necrosis, fibrosis and trabecular bone abnormalities. In light of these facts, the use of the term bone marrow oedema syndrome in a radiological context might be considered questionable, but histopathological techniques are not sensitive in detecting increased extracellular fluid. Reactive bone changes may be focal or diffuse and usually amount to increased bone formation. Bone marrow haemorrhage, due to trauma, results in bone bruising, a condition in which the size of the bruise and associated osteochondral injury determines the outcome, although the natural history of these lesions is still being researched

2

Reactive endosteal bone formation  

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The microstructure of reactive endosteal new bone was examined using undecalcified ground sections in five pathologic conditions (bone metastasis from prostate cancer in seven cases, intervertebral osteochondrosis in five, Paget disease in four, chronic suppurative osteomyelitis in two, and fracture healing in one). To determine a basic form of rapid intramembranous bone formation, fetal rat calvaria and primitive bones made in clonal osteogenic cell culture were also observed. In slow bone-forming conditions, lamellar new bone was deposited on pre-existing trabecular surface and caused trabecular thickening on radiographs. In contrast, in rapid bone-forming conditions, woven bone was deposited as spicules extending from trabecular surface so as to form new networks on intertrabecular space. This causes obscurity of trabecular margins radiographically. Reactive endosteal bone formation may be nonspecific and have a significance for assessing the virulence of underlying pathologic conditions like periosteal reactions.

Aoki, Jun; Yamamoto, Itsuo; Hino, Megumu; Kitamura, Nobuyasu; Sone, Teruki; Itoh, Harumi; Torizuka, Kanji

1987-10-01

3

On the molecular and endocrine mechanisms of postradiation changes in reactivity of bone tissues  

International Nuclear Information System (INIS)

The state of the production system of a specific hormone factor of controlling calciOm metabolism-calcitonin as well as metabolism and physicochemical, properties of collagenous matrix of bone tissue in irradiated rats of different ages, was studied. It is established that under 400 rad total X-ray irradiation there are the following considerable disturbances in albuminous matrix of bone tissue changes of the intensity of catabolic and anabolic processes as well as structural-molecular organization of collagen and its ripening. The degree and character of these disturbances depend on the age of irradiated animals and dynamics of radiation injury. Under ionizing radiation of a sublethal dose compensatory-adaptive reactions develop on the level of the hormonal control of bone metabolism for the conservation of the buffer homeostatic function of the bone system in maintaining calcium homeostasis. These mechanisms are disturbed at most at the preadolescent age

4

Reactive changes of disc space and foreign body granuloma due to bone wax in lumbar spine  

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Full Text Available Bone wax is a well-known agent used to prevent bleeding from the bone that can be used in different surgical procedures. Bone wax is a safe agent, but it may rarely lead to significant foreign body reactions. In this report, we present a patient who developed bone wax-related disc space foreign body granuloma following L4 total laminectomy, extremely rare complication.

Ozdemir Nail

2009-01-01

5

Roentgenologic bone changes in phenylketonuria  

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Objective: To report the bone X-ray changes in phenylketonuria. Methods: Thirty-seven cases of phenylketonuria were reported. Among the 37 cases, 25 were males and 12 were females. The age of this series ranged from 6 months to 9 years. X-ray examination of the hands, wrists, and knees and laboratory examination were performed in all cases. Results: The bone changes of the 37 cases were divided into 6 groups: no abnormal findings, osteoporosis, metaphyseal changes, special changes, the bone age method, and miscellaneous changes. Special changes included striations into the diaphysis (12 cases) and beak of the metaphyseal margin (21 cases). Conclusion: The mechanism causing the bone changes in phenylketonuria is not quite clear. The authors conclude that specific bone changes may be important X-ray signs suggestive of phenylketonuria

6

Quantitative and qualitative assessment of reactive hematopoietic bone marrow in aplastic anemia using MR spectroscopy with variable echo times  

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Objective: To assess quantitative and qualitative differences in water components between normal bone marrow and reactive hematopoietic marrow in aplastic anemia using magnetic resonance (MR) spectroscopy with variable echo times (TEs). Design: Water content, T2 value of the water component, and signal change in water related to TE were assessed in normal bone marrow and reactive hematopoietic bone marrow by a stimulated echo acquisition mode with TEs of 30, 45, 60, and 90 ms. Patients: Six patients with aplastic anemia (13-84 years) and seven normal volunteers (25-38 years) were examined. Results and conclusion: Reactive hematopoietic marrow showed significantly higher water content than normal bone marrow. The T2 value of water components tended to be longer in reactive hematopoietic marrow. Water signal ratio related to TE was significantly higher in reactive hematopoietic marrow. These results suggest a quantitative and qualitative difference in water components between normal and reactive hematopoietic bone marrow. (orig.)

7

Bone marrow changes in patients with thyroid carcinoma  

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In 62 patients with thyroid carcinoma 79 MRI bone marrow examinations and 48 bone marrow scintigraphies were recorded before or following radioiodine therapy, to study the extent of bone marrow expansion. The results of both methods were the same. In 34/79 investigations normal findings were seen, in 18 the bone marrow expanded to the middle third and in 26 to the distal third of the femur. One patient showed bone marrow expansion to the tibia. These results were compared with the following data: Histology of tumor, TNM-staging, time passed since thyroidectomy, accumulated doses of radioiodine therapy, results of 131I scintigraphy, hematological changes, thyroglobulin level, age and sex. No significant correlations were found between these and the bone marrow imaging results. Bone marrow changes in patients before radioiodine therapy were similar to those in patients treated with up to 48 GBq 131I. Blind biopsy of the posterior iliac crest in five patients showed slightly pathological reactive changes. In only 2/17 follow-up studies an increase of bone marrow expansion was seen. In 8 patients localized findings indicating malignant infiltration were observed. In 4/8 patients metastases of thyroid carcinoma were known or confirmed by pathological radioiodine uptake and in 2/8 metastatic involvement was assumed because of an increased thyroglobulin level. (orig.)

8

Bone changes in primary myogenic limb sarcomas  

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Of 55 patients with histologically varified primary myogenic limb sarcomas the authors observed 5 patients with rhabdomyosarcoma (RMS) and 2 with leiomyosarcoma (LMS) of the limbs accompanied by bone changes. RMS was characterized by an infiltrative type of bone involvement by a tumor (inhomogeneous edge destruction of varying depth), and bone atrophy was noted in the zone of contact with a tumor in LMS

9

Recent changes in anthropogenic reactive nitrogen compounds  

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Significant anthropogenic perturbations of the nitrogen cycle are the result of rapid population growth, with mounting need for food and energy production. The increase of reactive nitrogen compounds (such as NOx, HNO3, NH3, and N2O) has a significant impact on human health, environment, and climate. NOx emissions contribute to O3 chemistry, aerosol formation and acidic precipitation. Ammonia is a notable atmospheric pollutant that may deteriorate ecosystems and contribute to respiratory problems. It reacts with acidic gases to form aerosols or is deposited back to ecosystems. The application of fertilizers accounts for most of the N2O production, adding to greenhouse gas emissions. We analyze the change of some reactive nitrogen compounds based on observations, in eastern United States. Results show that the control of NOx and SO2 emissions over the last decades caused a significant decrease of acidic deposition. The nitrate deposition is highest in eastern US, while the ammonium ion concentration is highest in central US regions. Overall, the inorganic nitrogen wet deposition from nitrate and ammonium is enhanced in central, and eastern US. Research shows that sensitive ecosystems in northeastern regions exhibit a slow recovery from the accumulated effects of acidic deposition. Given the growing demand for nitrogen in agriculture and industry, we discuss possible pathways to reduce the impact of excess reactive nitrogen on the environment.

Andronache, Constantin

2014-05-01

10

Climate change impacts of US reactive nitrogen.  

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Fossil fuel combustion and fertilizer application in the United States have substantially altered the nitrogen cycle, with serious effects on climate change. The climate effects can be short-lived, by impacting the chemistry of the atmosphere, or long-lived, by altering ecosystem greenhouse gas fluxes. Here we develop a coherent framework for assessing the climate change impacts of US reactive nitrogen emissions, including oxides of nitrogen, ammonia, and nitrous oxide (N(2)O). We use the global temperature potential (GTP), calculated at 20 and 100 y, in units of CO(2) equivalents (CO(2)e), as a common metric. The largest cooling effects are due to combustion sources of oxides of nitrogen altering tropospheric ozone and methane concentrations and enhancing carbon sequestration in forests. The combined cooling effects are estimated at -290 to -510 Tg CO(2)e on a GTP(20) basis. However, these effects are largely short-lived. On a GTP(100) basis, combustion contributes just -16 to -95 Tg CO(2)e. Agriculture contributes to warming on both the 20-y and 100-y timescales, primarily through N(2)O emissions from soils. Under current conditions, these warming and cooling effects partially offset each other. However, recent trends show decreasing emissions from combustion sources. To prevent warming from US reactive nitrogen, reductions in agricultural N(2)O emissions are needed. Substantial progress toward this goal is possible using current technology. Without such actions, even greater CO(2) emission reductions will be required to avoid dangerous climate change. PMID:22547815

Pinder, Robert W; Davidson, Eric A; Goodale, Christine L; Greaver, Tara L; Herrick, Jeffrey D; Liu, Lingli

2012-05-15

11

[Changes of bone metabolism in diabetics].  

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The effect of impaired regulation of the glucose metabolism on the bone tissue metabolism is many-sided and very complicated. In most cases we observe an increased risk of fracture in people with diabetes. The reasons causing this condition are varied. Its main cause in diabetic patients is typically not the decrease in bone mineral density, it is rather deterioration of bone tissue and its structure. An important role of insulin and insulin resistance is beyond dispute, with numerous other factors at work, such as increased glycation of proteins, including increased glycation of collagen in bones, change in sclerostin production and levels, intervention in the pluripotent stem cells differentiation and reversal of their differentiation toward adipocytes and many more. Some antidiabetics, mainly oral, may also significantly contribute to the increased risk of fracture. Given the increasing incidence of both diseases, diabetes and osteoporosis, it will be also necessary to examine in greater detail their mutual relations and effects.Key words: antidiabetics - bone metabolism - diabetes mellitus - insulin resistance - osteoporosis. PMID:25294763

Pali?ka, Vladimír; Lesná, Jana; Pavlíková, Ladislava

2014-01-01

12

Bone morphogenetic protein 7 regulates reactive gliosis in retinal astrocytes and M?ller glia  

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Purpose The focus of this study was to determine whether bone morphogenetic proteins (BMPs) trigger reactive gliosis in retinal astrocytes and/or Müller glial cells. Methods Retinal astrocytes and the Müller glial cell line MIO-M1 were treated with vehicle, BMP7, or BMP4. Samples from the treated cells were analyzed for changes in gliosis markers using reverse transcriptase – quantitative PCR (RT-qPCR) and western blotting. To determine potential similarities and differences in gliosis states, control and BMP-treated cells were compared to cells treated with sodium peroxynitrite (a strong oxidizing agent that will bring about some aspects of gliosis). Last, mature mice were microinjected intravitreally with BMP7 and analyzed for changes in gliosis markers using RT-qPCR, western blotting, and immunohistochemistry. Results Treatment of retinal astrocyte cells and Müller glial cells with BMP7 regulated various reactive gliosis markers. When compared to the response of cells treated with sodium peroxynitrite, the profiles of gliosis markers regulated due to exposure to BMP7 were similar. However, as expected, the profiles including the oxidative agent and growth factor were not identical. Treatment of cells with BMP4, however, showed an attenuated response in comparison to peroxynitrite and BMP7 treatment. Injection of BMP7 into the mouse retina also triggered a reactive gliosis response 7 days after injection. Conclusions BMP7 induced changes in levels of mRNA and protein markers typically associated with reactive gliosis in retinal astrocytes and Müller glial cells, including glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), a subset of chondroitin sulfate proteoglycans (CSPGs), matrix metalloproteinases (MMPs), and other molecules.

Dharmarajan, Subramanian; Gurel, Zafer; Wang, Shoujian; Sorenson, Christine M.; Sheibani, Nader; Belecky-Adams, Teri L.

2014-01-01

13

Experimental change of reactivity of mesenteric microvessels  

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Changes in hemodynamic parameters due to the action of adrenalin in the microcirculatory channel of tissue mesentery treated locally with beta radiation were studied. The studies were made on the mesenteries of 35 white rats (male) weighing 150-250 g. The diameters and linear blood flow rates were measured before irradiation and after application of adrenalin (1:100,000 dilute, 0.15 ml) to the irradiated portions in the same vessels. After irradiation the action of the adrenalin often caused deeper disruption of the blood flow than was observed when it was applied to mesentery tissue of the intact animals. Three to 5 s after application of the adrenalin, in some cases there was a lengthened cessation of blood flow, and then the flow started slowly in the reverse direction. Sometimes the result of the action of the preparation was an irreversible stasis of the blood. In the next 2-3 min there was retardation, and then acceleration, with a jerky blood flow. All changes in the peripheral blood circulation occurred in the narrow vessels, but an ischemia was not observed. Mathematical analysis of the data from our experiments showed that with application of adrenalin on irradiated mesentery tissue the greatest decrease in cross-section area is in the small arterioles (42.5-7.5 ? dia), i.e. 53-43% of the initial value. The cross-section area of the capillaries (7.5-17.5 ?) of the arterial and venous terminals decrease an average of 33-30%. The least reaction was noted in the venules of 42-75 ? (21%). The blood flow rate decreased in all vessels of the microcirculatory channel of irradiated tissue mesentery after application of adrenalin. The greatest decrease was in the arterioles and the precapillaries(42-50%). In the capillaries (7.5-17.5 ?) there was a decrease in blood volume through them of 25-30%, and in the venules (42.5-72.5 ?), 18%. With even a very small ionizing radiation dose, in the tissues there were a number of vaso-active substances (to which, apparently, the fat cells contribute), which start to interact with the vessel walls. The reactivity of the micro vessels changes with combined use of the vaso-active substances

14

Radiographic study of bone changes on TMJ arthrosis  

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The author analyzed the morphologic changes of bone structures from 1256 radiographs of 314 patients with temporomandibular joint arthrosis, which were obtained by the oblique-lateral projection and orthopantomography. The interrelations of the bone changes and clinical symptoms were examined. Also, the positional relationships of condylar head, articular fossa and articular eminence in the mouth open and closed state were observed in the patients with bone changes. The results were as follows; 1. The most frequent bone change in the TMJ arthrosis was eburnation of cortical bone (35.64%) of total cases. Then came bone surface erosion and localized radiolucency (26.18%), marginal proliferation (9.7%) and flattening of articular surface (9.58%) in that order. 2. The most frequent site of bone change was articular eminence (41.70%). The came condylar head (21.09%) and articular fossa (20.73%) in that order. 3. In the patients with bone changes, their clinical symptoms were pain (51.55%), clicking sound during mandibular movement (37.71%) and limited mandibular movement (10.73%). In the patients complaining pain, their radiographs showed eburnation of cortical bone (30.68%), bone surface erosion and localized radiolucency (27.45%) and flattening in the (30.68%), bone surface erosion and localized radiolucency (27.45%) and flattening of articular surface (10.68%). 4. The condylar positional changes in the TMJ arthrosis patients with bone changes were as follows: in the mouh bone changes were as follows: in the mouth closed state, there were the widening of joint space in 624 cases (50.00%), the narrowing of joint space in 543 cases (43.47%) and bone on bone relationships in 82 cases (6.57%). In the mouth open state, there were forward positioning of the condyle in 332 cases (28.55%), limitation of movement in 332 cases (28.55%), bone on bone relationships in 248 cases (21.31%) and downward positioning of condyle in 217 cases (18.66%). Bone on bone relationships in 248 cases (21.32%) and downward positioning of condyle in 217 cases (18.66%). 5. In the TMJ arthrosis patients with bone changes, 1249 cases of abnormal condylar position in the mouth closed state and 1163 cases of abnormal condylar position in the mouth open state could be interpreted. so, for the radiographic interpretation of TMJ arthrosis, the reading of condylar positional changes as well as that of bond changes should be preformed and their interrelations should be profoundly considered.

15

Fabrication of reactive poly(vinyl alcohol) membranes for prevention of bone cement leakage.  

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Leakage of bone cement into the spinal canal has been reported to cause many adverse effects. In this study, we designed an implantable balloon kyphoplasty material that avoids cement leakage through the formation of covalent bonds with the bone cement. For this purpose, glycidyl methacrylate (GMA) was used as a reactive functional group attached to the poly(vinyl alcohol) (PVA) membrane. The prepared membrane adhered to poly(methyl methacrylate) (PMMA)-based bone cements within 10 min, which is the time required for PMMA polymerization in the bone cement. The bonding strength between the GMA-PVA membrane and the PMMA-based bone cement was higher than that for the original PVA membrane, likely because vinyl bonds form between the surface of the GMA-PVA membrane and the bone cement. Since the GMA-PVA membrane adhered firmly to the PMMA-based bone cement, the membrane was able to completely cover the PMMA-based bone cement. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 102B: 1786-1791, 2014. PMID:24700680

Inoue, Motoki; Sakane, Masataka; Taguchi, Tetsushi

2014-11-01

16

Injectable reactive biocomposites for bone healing in critical-size rabbit calvarial defects  

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Craniofacial injuries can result from trauma, tumor ablation, or infection and may require multiple surgical revisions. To address the challenges associated with treating craniofacial bone defects, an ideal material should have the ability to fit complex defects (i.e. be conformable), provide temporary protection to the brain until the bone heals, and enhance tissue regeneration with the delivery of biologics. In this study, we evaluated the ability of injectable lysine-derived polyurethane (PUR)/allograft biocomposites to promote bone healing in critical-size rabbit calvarial defects. The biocomposites exhibited favorable injectability, characterized by a low yield stress to initiate flow of the material and a high initial viscosity to minimize the adverse phenomena of extravasation and filter pressing. After injection, the materials cured within 10–12 min to form a tough, elastomeric solid that maintained mechanical integrity during the healing process. When injected into a critical-size calvarial defect in rabbits, the biocomposites supported ingrowth of new bone. The addition of 80 µg mL?1 recombinant human bone morphogenetic protein-2 (rhBMP-2) enhanced new bone formation in the interior of the defect, as well as bridging of the defect with new bone. These observations suggest that injectable reactive PUR/allograft biocomposites are a promising approach for healing calvarial defects by providing both mechanical stability as well as local delivery stability as well as local delivery of rhBMP-2. (paper)

17

Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice  

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Research highlights: ? Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. ? Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. ? Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1-/- mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1-/- mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm2) and strength (MPa) is diminished in Sod1-/- compared to WT mice. Femurs were obtained from male and female WT and Sod1-/- mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1-/- mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1-/- mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1-/- mice may represent an appropriate model for studying disease processes in aging bone.

18

Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice  

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. {yields} Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. {yields} Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1{sup -/-} mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1{sup -/-} mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm{sup 2}) and strength (MPa) is diminished in Sod1{sup -/-} compared to WT mice. Femurs were obtained from male and female WT and Sod1{sup -/-} mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1{sup -/-} mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1{sup -/-} mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1{sup -/-} mice may represent an appropriate model for studying disease processes in aging bone.

Smietana, Michael J. [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Arruda, Ellen M. [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Mechanical Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109 (United States); Program in Macromolecular Science and Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109 (United States); Faulkner, John A.; Brooks, Susan V. [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Molecular and Integrative Physiology, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Larkin, Lisa M., E-mail: llarkin@umich.edu [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Molecular and Integrative Physiology, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States)

2010-12-03

19

Bone and joint changes following electrical burn: plain radiographic findings  

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To evaluate the plain radiographic findings of bone and joint changes following electrical burn. This study involved 19 patients with 27 bone and joints regions which had suffered electrical injury. The most common input and output sites were, respectively, the hand(7/14) and foot (6/10). Three other sites were involved. Four cases involved osteomyelitis, and in four, amputation was performed. We observed bone and joint changes, changes following osteomyelitis and changes in the amputation stump. We analyzed the difference between input and output changes, and when this was interesting, the average time of onset was assessed. In bone and joint changes following electrical burn, the most frequent radiographic finding was joint contracture(n=3D16). Other findings included osteolysis(n=3D8), articular abnormalites (n=3D6), periostitis(n=3D5), fracture(n=3D5), acro-osteolysis(n=3D2), and heterotopic bone formation(n=3D2). In cases involving osteomyelitis(n=3D4), aggravation of underlying bone changes was noted. In electrical burn, various changes were noted in bone and joints, and input injury was more severe than that of output.=20.

Kim, Uk Jung; Lee, Eil Seong; Shim, Ya Seong; Kim, Seon Bok; Lee, Shin Ho; Jung, Hae Kyoung; Hwang, Dae Hyun; Kang, Ik Won [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

1998-10-01

20

Bone density, bone quality, and FRAX: changing concepts in osteoporosis management.  

Science.gov (United States)

Bone densitometry was originally developed to diagnose a high risk for fragility fractures in older postmenopausal women who may have primary osteoporosis. Its widespread availability, however, has led to its use in healthy peri- and premenopausal patients and the unexpected findings of low bone density in this group of patients. Their low bone density caused much uncertainty about the likelihood of fracture risk and what treatment might be needed. Conceptually, bone density reflected bone strength, and so a low density reflected increased fracture risk. Clinical experience and the results of pivotal studies of therapy for osteoporosis suggested that bone density was only partly responsible for skeletal strength. Many structural and material properties of bone, not measured by bone density, made it resist fracturing. Clinical risk factors helped determine these characteristics, albeit imperfectly, and aided clinicians decide whether and what treatment was needed. But now, new fracture risk assessment protocols (namely, FRAX, the WHO risk assessment tool) are available to help resolve this dilemma. This paper reviews some of the clinical observations that led to rethinking the concept bone density and bone strength and how it changes the clinical approach to therapy for the healthy young patient. PMID:23142334

Licata, Angelo A

2013-02-01

 
 
 
 
21

Ontogenetic change in temporal bone pneumatization in humans.  

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Pneumatization of the temporal bone is often included in descriptions of fossils and as a phylogenetic marker, but a number of questions about the evolution, growth, and development of the trait remain. Many studies have analyzed temporal bone pneumatization from a clinical perspective, but a systematic quantification of normal development of pneumatized spaces has not been conducted. In this study, ontogenetic change in the size and organization of temporal bone pneumatization is analyzed in a cross-sectional sample of humans. High resolution computed tomography scans of the temporal bone were acquired from a cross-sectional sample of humans (N = 28). Bone volume fractions, anisotropy, trabecular number, trabecular thickness, surface area, and volume were analyzed to provide information about the organization and size of pneumatized spaces across ontogeny. The results indicate that there are general and region-specific patterns of ontogenetic changes in the organization of pneumatized spaces. These changes reflect the transition from nonpneumatized bone to pneumatized bone. It also demonstrates that those regions that are pneumatized early in ontogeny (such as the mastoid antrum) continue to remodel after the initial period of pneumatization. The dynamic nature of temporal bone pneumatization over ontogeny suggests that this character requires careful consideration when used as a character for phylogenetic analyses. These results demonstrate the importance of comparing individuals from similar developmental stages, especially when completing quantitative analyses of the extent of pneumatization or organization of the spaces. PMID:21618436

Hill, Cheryl A

2011-07-01

22

Bone changes caused by experimental Solanum malacoxylon poisoning in rabbits  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to describe the bone changes observed after a daily oral administration of the calcinogenic plant Solanum malacoxylon (syn. S. glaucophyllum) (Sm) during 9 days. The Sm-poisoned rabbits had an increase of bone resorption in the endosteal surface of the cortical zone and als [...] o in the surface covered by osteoblasts of the primary and secondary spongiosa of the trabecular bone compartment. Moreover, the epiphyseal growth plates in long bones appeared narrower than in the control rabbits, with reduction of the proliferative and hyperthrophic chondrocyte zones. The electron microscopic study revealed a significant decrease of proteoglycans in the hyperthrophic chondrocyte zone evidenced by a significant reduction of rutenium red positive granules in the poisoned rabbit. Altogether, these data suggest that cell differentiation may play a pivotal role in the pathogenesis of Sm-induced bone lesions.

José Ignacio, Aguirre; María Soledad, Gomar; Silvio, Igal; María Alejandra, Quiroga; Enrique Leo, Portiansky; Eduardo Juan, Gimeno.

2005-03-01

23

In-vitro studies of change in edge detection with changes in bone density  

International Nuclear Information System (INIS)

Full text: Dual energy X-ray absorptiometry (DXA) requires edge detection software to identify the skeletal regions for quantitation of bone mineral density (BMD) and bone mineral content (BMC). As bone mass decreases, the detection of bone edges becomes more difficult and this potentially could cause errors in DXA estimations of areal BMD or BMC. To address this issue, we have used an in-vitro model to study the effects of 'bone loss' on calculated bone area, BMD and BMC. Multiple vertebral phantoms, of equal cross-sectional area but incrementally decreased areal BMD, were constructed using calcium sulphate hemihydrate. The weight of each phantom vertebra, measured accurately using an electronic balance, was used as an index of its true 'bone mass equivalent' (BME). The phantoms were scanned and analysed in the lumbar spine mode using a Lunar DPX-L (L) and Hologic QDR-1000 (H). The changes in BME were compared to changes in measured area, BMC and areal BMD. The results demonstrate that, in an in-vitro model, as bone mass decreases, measured bone area and consequently BMC will decrease as the edge detection algorithms have greater difficulty in detecting the true edges. In conclusion, in an in-vitro model, the DXA edge detection algorithms will underestimate bone area as bone mass decreases. This has potential implications for monitoring changes in bone mass in vivo

24

Reduced gap strains induce changes in bone regeneration during distraction.  

Science.gov (United States)

A bilateral New Zealand white rabbit model of distraction osteogenesis (DO) was used to investigate the relationship between strain environment and bone regeneration during limb lengthening. In seven (n = 7) rabbits, a stiffener was applied to the fixator on one side to reduce strains within the gap tissue after lengthening was completed. Animals were euthanized six days later and their distraction zones were harvested and analyzed for changes in new bone volume and architecture. Nonlinear finite element analyses (FEA) were performed to predict changes in the gap strain environment. FEA results predicted a nearly uniform sevenfold decrease in average strain measures within the distraction zone. No change in total average new bone volume and significant decreases in both bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) were observed in tibiae in which gap strains were reduced experimentally, compared to contralateral controls. These results suggest that fixator stiffening influenced the architecture but not the amount of newly formed bone. This animal model of distraction might be used to study the mechanisms by which strain fields affect events in bone repair and regeneration, such as cell proliferation, precursor tissue differentiation, and altered growth factor and nutrient delivery to tissues. PMID:10396702

Richards, M; Waanders, N A; Weiss, J A; Bhatia, V; Senunas, L E; Schaffler, M B; Goldstein, S A; Goulet, J A

1999-06-01

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MRI spectrum of bone changes in the diabetic foot  

International Nuclear Information System (INIS)

Purposes: (1) To assess the prevalence of bone marrow changes in the diabetic foot and (2) to discuss the clinical significance of these changes. Methods: 85 patients with radiographic and magnetic resonance imaging (MRI) foot examinations were selected. Inclusion criteria were clinical diagnosis of diabetes and bone changes on radiographs and MRI. The material was selected from the image storage (PACS) system. We searched for vascular (infarct and necrosis), traumatic (bruise and occult fractures), destruction and debris, dislocation, osteochondritis, osteomyelitis. Five patients had bilateral examinations. A total of 90 feet were evaluated. Results: From 90 feet, 17 (18.9%) presented with vascular changes, from them, 11 feet had infarct and 6 feet had necrosis. Twenty (22.2%) feet had traumatic changes; of them, 10 (50%) had edema on MRI. Five (25%) cases had occult fracture on MRI; and 5 (25%) had visible fracture on both X-ray and MRI. Bone destruction was detected in 8 (8.9%) feet. Bony debris was visualized in three of them. Bone dislocation was visualized in 11 (12.2%) feet. There was evidence of osteochondritis in twenty-four (26.7%) feet. Osteomyelitis was diagnosed in ten (11.1%) feet. Conclusion: Diabetic foot is a challenge for both clinicians and radiologists due to its complexity. The bone derangements inherent to the diabetic foot can be evaluated with high accuracy with MRI.

26

Investigation of bone marrow lymphocyte subsets in normal, reactive, and neoplastic states using paraffin-embedded biopsy specimens.  

Science.gov (United States)

Bone marrow lymphocyte subsets in normal and reactive states and in neoplastic diseases involving the marrow were investigated with a select panel of monoclonal antibodies reactive on routinely processed, paraffin-embedded trephine biopsy material. In all cases, the antibodies beta F1 and UCHL1 (CD45RO) stained virtually equal numbers of T cells (reactive and neoplastic), whereas antibody OPD4 stained only about one half of this number of T cells. Antibody L26 (CD20) stained B cells (reactive and neoplastic) in all specimens. The T-cell to B-cell ratio in the normal marrow was between 4:1 and 5:1, and a significant increase in T-cell numbers was observed in reactive and myelodysplastic states. A significant increase in B-cell numbers, however, was seen only in marrow infiltrated by B-cell lymphoma. Bone marrow exhibiting infiltrates of B-cell lymphoma, acute leukemia, or myeloproliferative disorders showed normal or decreased numbers of T cells. These findings show that antibodies UCHL1, beta F1, and L26 can be used to determine the numbers of B and T lymphocytes in paraffin-embedded, formalin-fixed bone marrow specimens and thus may help to distinguish reactive T lymphocytosis from B-cell lymphoma. PMID:8438787

Horny, H P; Wehrmann, M; Griesser, H; Tiemann, M; Bültmann, B; Kaiserling, E

1993-02-01

27

Approximate description of reactivity changes during xenon transients  

International Nuclear Information System (INIS)

The justification is discussed of an approximation in modelling transients due to power changes of a nuclear power plant, such as allows to simplify the calculation at the expense of lower accuracy. The procedure is based on the balance equations for the concentration of iodine and xenon nuclei and their solution, and is based on the assumption that the multiplicatin properties of the reactor core can be described using the coefficient of thermal availability. The steady-state change in reactivity is described as is its time course during the transition from the stabilized zero power level to a non-zero level. The approximation was tested on non-steady state power changes of the following types: step changes from lower power levels to higher and vice versa, staged monotonous and non-monotonous changes of power. The approximate calculation represents a significant saving of machine time at acceptable accuracy of result. (J.C.)

28

Aging changes in the bones - muscles - joints  

Science.gov (United States)

... knee joints may begin to lose joint cartilage (degenerative changes). The finger joints lose cartilage and the ... mainly because of shortening of the trunk and spine. Inflammation, pain, stiffness, and deformity may result from ...

29

Seasonal variations in indices of bone formation precede appropriate bone mineral changes in normal men  

International Nuclear Information System (INIS)

In 10 normal males aged 23-50 years measurements of serum alkaline phosphatase (s-AP) and the 24-h whole body retention of 99mTc-diphosphonate (WBR), as indices of bone formation, and the fasting urinary hydroxyproline:creatinine ratio (OHPr:Cr), as an index of bone resorption, were performed monthly from January 1983 to May 1984. Bone mineral content of the distal forearm (BMC) was measured in the middle of each quarter. From January to May BMC exhibited a reproducible, significant average increase of 2.5%, returning to baseline level between May and August. During the first quarter of both 1983 and 1984 a significant increase in s-AP and WBR was seen. Subsequently, during the second quarter of 1983, these variables fell below the mean of the year. Confirming their interrelationship, the deviations of s-AP and WBR were positively correlated throughout the study period (r = 0.51, P less than 0.05). Since the urinary OHPr:Cr ratio remained constant, the reported seasonal changes in bone mass of normal, adult males appear to result from primary changes in bone formation

30

Potentialphilicity and potentialphobicity: Reactivity indicators for external potential changes from density functional reactivity theory  

Science.gov (United States)

In analogy to the electrophilicity, we define potentialphilicity indicators that represent energetically favorable ways to change the external potential of a molecule at fixed electron number. Similarly, we define a potentialphobicity to represent the least favorable way to change the external potential of a molecule. The resulting indicators should be useful for describing how molecular geometries change and predicting favorable and unfavorable ways for a reagent to approach a molecule. The linear response function enters plays a very important role in this approach, analogous to the role of the hardness for the electrophilicity or the hardness kernel for the Fukui function. The mathematical properties of the response function and its implications for these reactivity indicators are discussed in depth.

Liu, Shubin; Li, Tonglei; Ayers, Paul W.

2009-09-01

31

Mycetoma bone changes as seen radiogicaly using conventional radiology  

International Nuclear Information System (INIS)

The radiological features of mycetoma were prospectively described in this study which included two hundred patients with mycetoma. Middle age males were predominant affected group. Black mycetoma was commonest type in various age groups in both sexes followed by yellow, white and red mycetoma in this frequency. The foot was the commonly affected site in all patients. Radiological examinations of the effected sites revealed, soft tissue mass in most of the patients (80%), of them; 36 patients (19%) had obliteration of facial plans and 22 patients (11%) had scattered multiple granulations. No soft tissue calcification was seen in this study. Bone involvement was seen in 45 patients (22.5) and that included periosteal reaction (22,5), cortical erosion (15%), osteoporosis (12.5%), scalloping (11.5%), selerosis(4.5%) and tranlucence (7.5) osteolytic changes (1.5%) pseudocystic spaces without any new bone formation were seen. Intercommunication of the abscess cavities seen in the affected bone were shown as a net like or honey comb appearance. The most remarkable feature in all patients was the absence of sequestra and pathological feature even in patients with massive mycetoma. Few patients (24.5%) presented with sinuses without bone involvement. There was significant correlation between the bone changes and the type of mycetoma, duration of illness, sinus formation and recurrence rate. The painless nature of the disease most probably had contribute to the formation of thably had contribute to the formation of the bone changes as most patients present late in the course of the disease. Radiological examination of the mycetoma patients is useful for both diagnosis of the disease and follow up of patients and it should be routinely performed. (Author)

32

Radiodiagnosis of bone changes in diabetes mellitus  

International Nuclear Information System (INIS)

The results of analysis of roentgenograms and scintigrams of hands and feet of 21 patients with diabetes mellitus are presented. Scintigraphy was carried out with 99mTc-pyrophosphate. The examination was conducted with ON-110 gamma chamber. Changes in scintigrams are detected for 19 of 21 patients examined; 37 foci of pathologic buildup of radiopharmaceuticals are determined. Increased buildup of radiopharmaceuticals in the region of the focus isn't marked in roentgeograms for 48.6% of patients. For 51.4% of patients the results of both methods coincide. Scintigraphy with 99mTc-pyrophosphates allows to refiny the degree of osteal changes propagation in diabetes mellitus as well as to detect them earlier than by the roentgenologic method

33

Age-related changes in the biochemical properties of human cancellous bone collagen: relationship to bone strength  

DEFF Research Database (Denmark)

The metabolism of bone collagen has received little attention in relation to age-related loss of bone mass and strength. The aim of the present study was to analyze bone collagen content and metabolism in human bone with respect to age. The material consisted of iliac crest bone biopsies from 94 individuals: 46 women (ages 18-96, mean age 60.8 years) and 48 men (ages 23-92, mean age 59.5 years). Excluded from the study were all individuals with known osteoporotic lumbar vertebral fractures and renal, hepatic, or malignant diseases. Prior to collagen analysis the biopsies were scanned in a pQCT scanner for density assessment and then tested biomechanically. The results showed a decline in apparent bone density with age (P <0.0001), a decline in maximum stress, Young's modulus, and energy absorption with age (P <0.001). Concomittantly, there was an age-related decline in the intrinsic collagen content with age (P <0.001). However, there were no biochemical modifications of the bone collagen during aging. There were no significant differences between women and men in the slopes of the regressions-curves. When multiple regression analyses were performed, only apparent bone density came out as a significant contributor in the correlation to biomechanical properties. Nevertheless, the decrease in bone collagen content with age might indicate an increase in the mineralization degree (probably due to decreased bone turnover) and thereby a change in material properties of bone. In conclusion, the present study has shown that loss of bone mass plays the major role in loss of bone strength. However, there is also a change in bone composition during normal aging, leading to a decrease in collagen content and an increase in the degree of mineralization. At this skeletal site, in a normal population there was no change in the biochemical properties of bone collagen.

Bailey, Allen J; Sims, Trevor J

1999-01-01

34

Change in surface morphology of polytetrafluoroethylene by reactive ion etching  

International Nuclear Information System (INIS)

Polytetrafluoroethylene (PTFE) was exposed to Ar, CF4, N2 and O2 plasmas using a reactive ion etching facility. After the exposure, the change in the surface morphology of PTFE was examined and characterization studies were performed for the etching rate, surface roughness, radical yields, chemical structures, water repellency and so on. The etching rates of Ar, CF4, N2 and O2 plasmas were 0.58, 7.2, 4.4 and 17 ?m/h, respectively. It was observed that needle-like nano-fiber structures on the surface were irregularly fabricated by the CF4 plasma. In addition, when the water repellency of exposed samples was evaluated by contact angle, they showed super-hydrophobic properties: contact angle over 150o.

35

Increase of bone marrow lymphocytes in systemic mastocytosis: reactive lymphocytosis or malignant lymphoma? Immunohistochemical and molecular findings on routinely processed bone marrow biopsy specimens  

Science.gov (United States)

Aims: To clarify the nature (reactive or neoplastic) of lesional, perifocally aggregated lymphocytes in bone marrow infiltrates of systemic mastocytosis (SM), the histopathology of which can resemble malignant lymphoma with focal bone marrow involvement, particularly low grade malignant B cell lymphoma of lymphoplasmacytic immunocytoma subtype, which frequently exhibits increased mast cell (MC) numbers. Methods: Thirteen cases of SM and three of lymphoplasmacytic immunocytoma with predominant focal bone marrow infiltration were investigated. Immunostaining of formalin fixed, paraffin wax embedded bone marrow specimens was performed using antibodies against CD2, CD5, CD20, CD23, and CD25; ? and ? immunoglobulin light chains; and MC markers chymase, tryptase, and CD117 (KIT). Monoclonal rearrangements of IgH and TCR? were studied using seminested polymerase chain reaction (PCR). c-kit point mutation Asp816-Val was detected by PNA mediated PCR clamping and hybridisation probes. Results: The lymphocytic clusters in SM contained nearly equal numbers of mature T and B cells, the latter with no coexpression of aberrant antigens, such as CD5 or CD23. Most MCs in SM cases constantly coexpressed tryptase, CD25, and CD117. No monoclonal rearrangements were seen for IgH or TCR?. In contrast, B cells from immunocytomas showed light chain restriction and monoclonal rearrangement for IgH, confirming their neoplastic nature. c-kit point mutation Asp816-Val was found in ten of 13 SM cases, but in none of the three immunocytomas. Conclusions: Focal accumulations of lymphocytes in the bone marrow of SM are reactive in nature and could be termed lymphocytosis. A diagnosis of SM-AHNMD/immunocytoma should not be made. PMID:12890804

Horny, H-P; Lange, K; Sotlar, K; Valent, P

2003-01-01

36

Adipokines and C-reactive protein in relation to bone mineralization in pediatric nonalcoholic fatty liver disease  

Digital Repository Infrastructure Vision for European Research (DRIVER)

AIM: To investigate bone mineral density (BMD) in obese children with and without nonalcoholic fatty liver disease (NAFLD); and the association between BMD and serum adipokines, and high-sensitivity C-reactive protein (HSCRP). METHODS: A case-control study was performed. Cases were 44 obese children with NAFLD. The diagnosis of NAFLD was based on magnetic resonance imaging (MRI) with high hepatic fat fraction (? 5%). Other causes of chronic liver disease were ruled out. Controls were s...

Lucia Pacifico; Mario Bezzi; Concetta Valentina Lombardo; Sara Romaggioli; Flavia Ferraro; Stefano Bascetta; Claudio Chiesa

2013-01-01

37

Lectin histochemistry of human bone marrow: investigation of trephine biopsy specimens in normal and reactive states and neoplastic disorders.  

Science.gov (United States)

The lectin binding pattern of bone marrow cells in normal and reactive states and in various neoplastic disorders was investigated using trephine biopsy specimens taken from the iliac crest. The tissue samples were routinely processed (fixed in formalin and embedded in paraffin wax) and subjected to mild decalcification with EDTA. The following results were obtained. (1) More than half of the 23 fluoresceinated lectins used reacted with normal blood cells and/or their neoplastic derivatives. Inhibition tests with the appropriate sugars confirmed the specificity of binding for the majority, but not all, of the lectins. (2) WGA, Con A, PSA, STA and RCA60 and RCA120 produced a particularly intense reaction with normal, reactive and neoplastic myeloid cells. Erythroblasts exhibited weak staining in a few cases by a few lectins (WGA producing the strongest staining), while megakaryocytes nearly always remained unstained. Neoplastic lymphoid cells in various lymphoproliferative disorders and plasmacytoma cells generally reacted with the same lectins as the myeloid cells. (3) Since neoplastic myeloid cells in various myelodysplastic and myeloproliferative disorders exhibited a lectin binding pattern similar to that of myeloid cells in normal and reactive bone marrow, it is unlikely that lectin histochemistry of the bone marrow will prove of great value in the diagnosis of myelodysplastic-myeloproliferative disorders. PMID:1783564

Schumacher, U; Horny, H P; Welsch, U; Kaiserling, E

1991-05-01

38

Analysis of changes in bone cement damping factor and its effect on bone load  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: The article presents the results of simulations and material-related investigations for bone cement used for alloplasty of hip joint. Mechanical properties of bone cements are of key importance for a successful surgery and further use of the joint as well as its behaviour during complex load which appears during patient’s walk.Design/methodology/approach: One of the methods of thermal analysis for polymeric materials has been used for investigations. DMTA method is based on the analysis of the signal (reaction from the deformed material under particular conditions, at the changeable ambient temperature as well as frequency and amplitude of vibrations. DMTA thermograms give information on change in storage modulus E’ and the mechanical loss factor tg?, which is responsible for dissipation of energy during deformation.Findings: During simulation investigations ADINA engineering environment has been used; it enabled, at the assumed boundary and initial conditions, to assess the stress which appears in individual cross-sections of the analysed bone and the implant fixed by means of bone cement. During the analysis the cross-sections have been presented and the values of the stress which appears in individual zones have been determined.Research limitations/implications: Due to high complexity, only the results of simulation software have been used, clinic trials will be possible not before thorough check and analysis of the obtained results.Practical implications: Practical application of the results of the investigations described in this paper will be possible after long and comprehensive clinical trials.Originality/value: Original value of this paper are the results of tests since such an analysis has never been conducted by scientific environment working on this subject.

P. Postawa

2007-07-01

39

Changes in the Mechanical Properties and Composition of Bone during Microdamage Repair  

Science.gov (United States)

Under normal conditions, loading activities result in microdamage in the living skeleton, which is repaired by bone remodeling. However, microdamage accumulation can affect the mechanical properties of bone and increase the risk of fracture. This study aimed to determine the effect of microdamage on the mechanical properties and composition of bone. Fourteen male goats aged 28 months were used in the present study. Cortical bone screws were placed in the tibiae to induce microdamage around the implant. The goats were euthanized, and 3 bone segments with the screws in each goat were removed at 0 days, 21 days, 4 months, and 8 months after implantation. The bone segments were used for observing microdamage and bone remodeling, as well as nanoindentation and bone composition, separately. Two regions were measured: the first region (R1), located 1.5 mm from the interface between the screw hole and bone; and the second region (R2), located>1.5 mm from the bone-screw interface. Both diffuse and linear microdamage decreased significantly with increasing time after surgery, with the diffuse microdamage disappearing after 8 months. Thus, screw implantation results in increased bone remodeling either in the proximal or distal cortical bone, which repairs the microdamage. Moreover, bone hardness and elastic modulus decreased with microdamage repair, especially in the proximal bone tissue. Bone composition changed greatly during the production and repair of microdamage, especially for the C (Carbon) and Ca (Calcium) in the R1 region. In conclusion, the presence of mechanical microdamage accelerates bone remodeling either in the proximal or distal cortical bone. The bone hardness and elastic modulus decreased with microdamage repair, with the micromechanical properties being restored on complete repair of the microdamage. Changes in bone composition may contribute to changes in bone mechanical properties. PMID:25313565

Yu, Zhifeng

2014-01-01

40

Induction of systemic bone changes by preconditioning total body irradiation for bone marrow transplantation  

International Nuclear Information System (INIS)

Preconditioning total body irradiation (TBI) prior to bone marrow transplantation (BMT) has been believed to be a safe procedure that does not cause late morbidity; yet, a recent report raises the suspicion that TBI-induced chondroosseous abnormalities do occur. To evaluate the radiological manifestations of TBI-induced skeletal alterations and their orthopaedic morbidity. Subjects included 11 children with TBI-induced skeletal changes, including 9 in our hospital and 2 in other hospitals. The former were selected from 53 children who had undergone TBI with BMT. Radiographic examinations (n=11), MRI (n=3), CT (n=2), and medical records in the 11 children were retrospectively reviewed. The skeletal alterations included abnormal epiphyseal ossification and metaphyseal fraying (8/11), longitudinal metaphyseal striations (8/11), irregular metaphyseal sclerosis (6/11), osteochondromas (4/11), slipped capital femoral epiphysis (2/10), genu valgum (3/10), and platyspondyly (2/3). MRI demonstrated immature primary spongiosa in the metaphysis. Of the 11 children, 9 had clinical symptoms. TBI can induce polyostotic and/or generalized bone changes, mainly affecting the epiphyseal/metaphyseal regions and occasionally the spine. The epi-/metaphyseal abnormalities represent impaired chondrogenesis in the epiphysis and growth plate and abnormal remodelling in the metaphysis. Generalized spine changes may lead to misdiagnosis of a skeletal dysplasia. (orig.)

 
 
 
 
41

Induction of systemic bone changes by preconditioning total body irradiation for bone marrow transplantation  

Energy Technology Data Exchange (ETDEWEB)

Preconditioning total body irradiation (TBI) prior to bone marrow transplantation (BMT) has been believed to be a safe procedure that does not cause late morbidity; yet, a recent report raises the suspicion that TBI-induced chondroosseous abnormalities do occur. To evaluate the radiological manifestations of TBI-induced skeletal alterations and their orthopaedic morbidity. Subjects included 11 children with TBI-induced skeletal changes, including 9 in our hospital and 2 in other hospitals. The former were selected from 53 children who had undergone TBI with BMT. Radiographic examinations (n=11), MRI (n=3), CT (n=2), and medical records in the 11 children were retrospectively reviewed. The skeletal alterations included abnormal epiphyseal ossification and metaphyseal fraying (8/11), longitudinal metaphyseal striations (8/11), irregular metaphyseal sclerosis (6/11), osteochondromas (4/11), slipped capital femoral epiphysis (2/10), genu valgum (3/10), and platyspondyly (2/3). MRI demonstrated immature primary spongiosa in the metaphysis. Of the 11 children, 9 had clinical symptoms. TBI can induce polyostotic and/or generalized bone changes, mainly affecting the epiphyseal/metaphyseal regions and occasionally the spine. The epi-/metaphyseal abnormalities represent impaired chondrogenesis in the epiphysis and growth plate and abnormal remodelling in the metaphysis. Generalized spine changes may lead to misdiagnosis of a skeletal dysplasia. (orig.)

Miyazaki, Osamu; Okamoto, Reiko; Masaki, Hidekazu [National Centre for Child Health and Development, Department of Radiology, Tokyo (Japan); Nishimura, Gen [Tokyo Metropolitan Kiyose Children' s Hospital, Department of Radiology, Tokyo (Japan); Kumagai, Masaaki; Shioda, Yoko [National Centre for Child Health and Development, Department of Oncology, Tokyo (Japan); Nozawa, Kumiko [Saitama Children' s Medical Centre, Department of Radiology, Saitama (Japan); Kitoh, Hiroshi [Nagoya University Hospital, Department of Orthopaedic Surgery, Nagoya, Aichi (Japan)

2009-01-15

42

Differences in origin of reactive microglia in bone marrow chimeric mouse and rat after transient global ischemia  

DEFF Research Database (Denmark)

Current understanding of microglial involvement in disease is influenced by the observation that recruited bone marrow (BM)-derived cells contribute to reactive microgliosis in BM-chimeric mice. In contrast, a similar phenomenon has not been reported for BM-chimeric rats. We investigated the recruitment and microglial transformation of BM-derived cells in radiation BM-chimeric mice and rats after transient global cerebral ischemia, which elicits a characteristic microglial reaction. Both species displayed microglial hyperplasia and rod cell transformation in the hippocampal CA1 region. In mice, a subpopulation of lesion-reactive microglia originated from transformed BM-derived cells. By contrast, no recruitment or microglial transformation of BM-derived cells was observed in BM-chimeric rats. These results suggest that reactive microglia in rats originate from resident microglia, whereas they have a mixed BM-derived and resident origin in mice, depending on the severity of ischemic tissue damage.

Lambertsen, Kate Lykke; Deierborg, Tomas

2011-01-01

43

Chronic radium intoxication: preliminary report of morphological and mineral changes in human bone  

International Nuclear Information System (INIS)

Observations are presented on bone microradiograms from 44 radium patients. The data cover three basic categories of mineral changes: (1) increase in bone mineral resorption, (2) increase in bone mineral density and (3) increase in new bone tissue formation. The data show a trend of increasing amount of mineral change in all three categories as the cumulative rads, cumulative rad-years, and amount of radium intake increase

44

Polyneuritic leprosy presenting with bone changes prior to the onset of florid skin manifestation  

Directory of Open Access Journals (Sweden)

Full Text Available A case of polyneuritic leprosy is reported. There were minimal changes on skin, but changes in the bones were predominant. It is emphasized that polyneuritic leprosy is an entity. It is also stressed that neuritic leprosy can produce changes in deeper structures like bones, with minimal changes on skin.

Kuravi Anandam

2001-01-01

45

Scintigraphic changes in bone metastasis from prostate cancer after hormonal therapy. Comparison with tumor markers and bone X-ray  

International Nuclear Information System (INIS)

Bone scintigraphy is often performed to assess the response to systemic therapy of bone metastasis from prostate cancer. We examined the changes in bone scintigraphic findings and the agreement with alkaline phosphatase(AlP), acid phosphatase(AcP), or other tumor markers measured in the follow-up of patients with known bone metastasis after hormonal therapy. Out of 32 patients, 22 (69%) showed improved scintigraphic findings on the first follow-up bone scintigraphy after hormonal therapy. However, 7 out of 22 patients who showed improvement on the first follow-up scintigraphy, deteriorated thereafter. Changes in the scintigraphic findings were closely correlated with those in the measured tumor markers except for patients with small bone metastasis. Though there were no significant differences in the agreement ratios of the 6 tumor markers evaluated, AlP might be a practical and acceptable indicator. Bone X-ray findings did not change at all in almost half of the cases though the scintigraphic findings showed improvement or deterioration. (author)

46

Late bone and soft tissue changes of the terminal digit after mild trauma  

Energy Technology Data Exchange (ETDEWEB)

Mechanical injuries to the terminal digit with or without bone involvement may lead to delayed changes involving a spongey hyperostosis of the tuberosities and hypertrophy of bone and soft tissues. In its most severe form it may lead to posttraumatic finger clubbing. These late results persist for many decades, despite juvenile growth and bone apposition in adult life.

Fischer, E.

1983-02-01

47

Late bone and soft tissue changes of the terminal digit after mild trauma  

International Nuclear Information System (INIS)

Mechanical injuries to the terminal digit with or without bone involvement may lead to delayed changes involving a spongey hyperostosis of the tuberosities and hypertrophy of bone and soft tissues. In its most severe form it may lead to posttraumatic finger clubbing. These late results persist for many decades, despite juvenile growth and bone apposition in adult life. (orig.)

48

Using Natural Stable Calcium Isotopes to Rapidly Assess Changes in Bone Mineral Balance Using a Bed Rest Model to Induce Bone Loss  

Science.gov (United States)

Metabolic bone diseases like osteoporosis result from the disruption of normal bone mineral balance (BMB) resulting in bone loss. During spaceflight astronauts lose substantial bone. Bed rest provides an analog to simulate some of the effects of spaceflight; including bone and calcium loss and provides the opportunity to evaluate new methods to monitor BMB in healthy individuals undergoing environmentally induced-bone loss. Previous research showed that natural variations in the Ca isotope ratio occur because bone formation depletes soft tissue of light Ca isotopes while bone resorption releases that isotopically light Ca back into soft tissue (Skulan et al, 2007). Using a bed rest model, we demonstrate that the Ca isotope ratio of urine shifts in a direction consistent with bone loss after just 7 days of bed rest, long before detectable changes in bone mineral density (BMD) occur. The Ca isotope variations tracks changes observed in urinary N-teleopeptide, a bone resorption biomarker. Bone specific alkaline phosphatase, a bone formation biomarker, is unchanged. The established relationship between Ca isotopes and BMB can be used to quantitatively translate the changes in the Ca isotope ratio to changes in BMD using a simple mathematical model. This model predicts that subjects lost 0.25 0.07% ( SD) of their bone mass from day 7 to day 30 of bed rest. Given the rapid signal observed using Ca isotope measurements and the potential to quantitatively assess bone loss; this technique is well suited to study the short-term dynamics of bone metabolism.

Morgan, J. L. L.; Skulan, J. L.; Gordon, G. E.; Smith, Scott M.; Romaniello, S. J.; Anbar, A. D.

2012-01-01

49

Magnetic resonance imaging of bone marrow changes after irradiation  

Energy Technology Data Exchange (ETDEWEB)

Signal changes of irradiated bone marrow are thought to represent fatty change. However, more recent studies have indicated that other factors may contribute to these signal changes. We performed animal studies to investigate magnetic resonance (MR) signal change factors in correlation with histologic findings. Forty-two male Wister rats were given single doses (3, 8, and 20 Gy) of irradiation. Magnetic resonance imaging (1.5 T) was performed using spin-echo technique. In the acute phase (days 1-3), the T1 time was prolonged, probably secondary to decreased cellularity and edema. After this phase, the irradiated marrow showed marked T1 and T2 shortening that correlated with hemorrhage. In the chronic phase (after day 10), fatty replacement, fibrosis, and regeneration were observed. T2 times were stable in spite of regeneration because of the susceptibility effect of hemosiderin. The MR signal changes of irradiated marrow reflect not only fatty replacement, but hemorrhage as well. 14 refs., 6 figs.

Sugimura, Hiroshi; Tamura, Shozo; Kihara, Yasushi; Watanabe, Katsushi; Kisanuki, Atsushi; Sumiyoshi, Akinobu (Miyazaki Medical College (Japan))

1994-01-01

50

Galloping exercise induces regional changes in bone density within the third and radial carpal bones of Thoroughbred horses  

International Nuclear Information System (INIS)

This study was performed to test the hypothesis that a localised bone hypertrophy could occur within the subchondral cancellous architecture of the third and radial carpal bones. Using 2 levels of controlled and defined exercise, it was observed that a high intensity treadmill exercise protocol resulted in functional adaptation of the carpal bones. The increase in trabecular thickening and density was seen to be localised to those regions underlying common sites of cartilage degradation, the interface of the thickened trabeculae with the normal architecture in the third carpal hone was coincident with a common site of clinical fractures. The bone changes were determined both qualitatively on examination of slab radiographs and quantified by dual energy x-ray absorptiometry. The findings from this study are relevant to mechanical factors involved in the pathophysiology of joint degeneration. The potential clinical implications of this study are in relation to changes in the type and duration of exercise regimens used in training of equine athletes. The rapid response of bone to mechanical stimulation has implications in the longer term for localised cartilage degradation. Imaging techniques could be developed to monitor these early bone changes in the specific areas identified in this study and thus allow appropriate changes in training intensity to minimise subsequent damage to the articular surface

51

Changes in autoimmune thyroid disease following allogeneic bone marrow transplantation.  

Science.gov (United States)

Autoimmune diseases can be transmitted and eliminated by bone marrow transplantation (BMT). There have been several cases of autoimmune thyroid disease (AITD) occurring after BMT, but AITD remission has been rarely reported. We present four cases in which the remission or transfer of AITD occurred after an allogeneic BMT. Two patients with severe aplastic anemia (SAA) showed evidence of remission of Hashimoto's thyroiditis which they had before allogeneic BMT. One patient with SAA, which developed during treatment with propylthiouracil for Graves' disease, underwent allogeneic BMT and showed evidence of Graves' disease remission following BMT. In one patient, new AITD occurred after an allogeneic BMT from an HLA-matched sibling who already had AITD. These cases support the evidence that the immune system is newly reconstituted after BMT, and severe autoimmune disease can be an indication for BMT. To fully understand the real changes in autoimmune status after BMT, long-term prospective studies are necessary. PMID:11498746

Lee, W Y; Oh, E S; Min, C K; Kim, D W; Lee, J W; Kang, M I; Min, W S; Cha, B Y; Lee, K W; Son, H Y; Kang, S K; Kim, C C

2001-07-01

52

Calculation of reactivity changes due to bubble collapse  

International Nuclear Information System (INIS)

Calculations based on Behrens' method indicate that a substantial increase in reactivity may accompany the collapse of a large number of small bubbles in an LMFBR core. More sophisticated transport approaches to this problem have encountered several difficulties: the large number of bubbles requires many mesh points; the desired effect can easily be masked by the movement of fuel to regions of greater (or lesser) importance; the reactivity is desired for a random distribution of spherical bubbles. This paper describes a transport approach to this problem which avoids the above difficulties by using the ''sub-group'' or ''probability table'' method

53

Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice.  

Science.gov (United States)

Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1(-/-) mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1(-/-) mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm(2)) and strength (MPa) is diminished in Sod1(-/-) compared to WT mice. Femurs were obtained from male and female WT and Sod1(-/-) mice at 8months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1(-/-) mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1(-/-) mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1(-/-) mice may represent an appropriate model for studying disease processes in aging bone. PMID:21056548

Smietana, Michael J; Arruda, Ellen M; Faulkner, John A; Brooks, Susan V; Larkin, Lisa M

2010-12-01

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Cardiovascular changes during vertebroplasty do not due to bone cement leakage  

International Nuclear Information System (INIS)

The rather serious complication of vertebroplasty is caused by bone cement leakage into adjacent structure but recent research suggests that even without cement leakage during vertebroplasty, patients could also experience with cardiovascular changes sometimes. Cytotoxicity of bone cement, nervous reflex, fat embolism and alteration of intravertebral pressure may be responsible for these changes. (authors)

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Reactive and neoplastic lymphocytes in human bone marrow: morphological, immunohistological, and molecular biological investigations on biopsy specimens.  

Science.gov (United States)

BACKGROUND: Slight, diffuse or focal lymphocyte proliferation is relatively common in bone marrow biopsy specimens. It may be impossible to determine whether this represents a reactive lymphocytosis or low grade non-Hodgkin lymphoma (NHL) on the basis of routine investigations alone. AIM: To investigate the supplementary use of molecular biological techniques in this situation. METHODS: 529 formalin fixed, paraffin embedded bone marrow biopsy specimens from the iliac crest were subjected to histological and immunohistochemical staining to determine the number and nature of the lymphocytes present. The cases were divided into three groups according to the lymphocyte count: normal ( 30%). All of the last group could be diagnosed as NHL from the morphological findings alone. The clonality of rearrangements of the IgH and TCR gamma genes was investigated by polymerase chain reaction (PCR). RESULTS: Monoclonality was observed in 7.5% of the 372 cases with a normal lymphocyte count, in 50% of the cases with a modest increase in lymphocyte numbers (suggesting a diagnosis of low grade NHL not detected by immunostaining), and in 77% of the cases with markedly increased lymphocyte numbers. CONCLUSIONS: If PCR is used in addition to the immunohistochemical investigation of bone marrow biopsies, considerably more cases of NHL can be identified, making this of particular use in staging and detection of recurrences. Images PMID:10605406

Krober, S M; Horny, H P; Greschniok, A; Kaiserling, E

1999-01-01

56

Early-age volume changes of extrudable reactive powder concrete  

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Full Text Available This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs, especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP, have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

De Noirfontaine M.N.

2010-06-01

57

Primary hyperparathyroidism : changes in trabecular bone remodeling following surgical treatment--evaluated by histomorphometric methods  

DEFF Research Database (Denmark)

Iliac bone biopsies from 11 patients who underwent successful surgery for primary hyperparathyroidism were examined before and median 7 months after surgical treatment. Trabecular bone volume increased (p less than 0.05) and eroded (p less than 0.005) and osteoid covered surfaces decreased (p less than 0.005) in the postoperative period. Also, a decline in tetracycline labeled surfaces was noticed (p less than 0.02). Osteoid thickness, mineral appositional rate and mineralization lag time were unchanged. Bone formation rate at the level of the basic multicellular unit (BMU) was unaffected, but at the tissue level bone formation rate diminished (p less than 0.02). The surgical cure of primary hyperparathyroidism was found accompanied by a change in bone metabolism as the trabecular bone remodeling decreased from a high turnover to a low turnover state. The spongy bone mass increased after parathyroidectomy but the clinical significance of this finding was not clear.

Christiansen, Peer Michael; Steiniche, T

1990-01-01

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Relationship between Coronary Risk Factors, C-Reactive Protein, Bone Mineral Density and Carotid Circulation Among Frail Elderly  

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Full Text Available Background: Frailty may now be regarded as a geriatric syndrome of decreased reserve and resistance to stressors, resulting from cumulative declines across multiple physiologic systems, causing vulnerability to adverse health outcomes including falls, hospitalisation, institutionalisation and mortality. The inflammatory mediators as C-reactive protein have been associated with the development of the geriatric frailty. Several studies have pointed out increased level of homocystiene in frail elderly Increasing frailty was associated with lower bone mineral density, as both bone mass and muscle strength decrease during ageing and this has also been associated with higher risk of osteoporotic fractures in frail elderly. Objective: To compare frail and non-frail elderly regarding Bone mineral density, carotid circulation and serum levels of Homocysteine, coronary risk factors and CRP. Methods: 104 elderly patients, who were assigned to 2 groups. Group A (52 frail participants: diagnosed by Fried’s criteria as applied by Avila-Funes et al., 2008. Group B (52 non-frail participants.All participants were subjected to the following: through history, physical examination, ADL, IADL assessment, MMSE ,GDS, laboratory investigations including; CRP, homocystiene and total lipid profile, measurement of bone mineral density by DEXA and carotid intima-media thickness by carotid duplex. Results: There was no statistically significant difference in age, sex, among both groups.Frail participants had higher ADL and IADL dependence, higher incidence of depression, cognitive impairment and osteoprosis.They also had higher levels of homocystiene , CRP , CIMT and lower levels of HDL cholesterol. Conclusion: Osteoporosis is more prevalent among frail elderly also frailty is associated with more ADL & IADL dependence, higher GDS scores & lower MMSE score in addition to higher mean level of homocystiene, CRP & triglycerides in addition to low serum HDL & higher CIMT

Moatassem S. Amer1, Tamer M. Farid1, Ekrami E. Abdel-rahman1,

2014-06-01

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Calculations of Changes in Reactivity during some regular periods of operation of JEN-1 MOD Reactor  

International Nuclear Information System (INIS)

By a Point-Reactor model and Perturbation Theory, changes in reactivity during some regular operating periods of JEN-1 MOD Reactor have been calculated and compared with available measured values. they were in good agreement. Also changes in reactivity have been calculated during operations at higher power levels than the present one, concluding some practical consequences for the case of increasing the present power of this reactor. (Author)

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Study of changes in antioxidant protective system activity in animal tissues in a bone defect model  

International Nuclear Information System (INIS)

In the present work changes of the activity of antioxidant protective system in a bone defect model were studied by evaluation of endogenous tocopherols, antiradical activity, and antioxidant enzyme superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity. It has been shown that 1*0.5 sm shaft of femur defect model causes significant decrease of tissue antiradical activity values, the level of endogenous tocopherols, SOD and GPx in periosteum, bone marrow, liver and blood. This process occurs more drastically on the background of autoplastic substitution of the defect. In a bone defect the largest changes were observed in antiradical activity and GPx activity in periosteum and bone marrow. Analysis of obtained data unambiguously suggests the necessity of correction of tissue antioxidant activity disorders in bone defect for thye prevention of the lipid peroxidation that causes possible complications and reparative bone regeneration suppression

 
 
 
 
61

Bone changes associated with soft-tissue tumors of the hand.  

Science.gov (United States)

The purpose of this study was to clarify clinical and radiographic features of bone changes associated with soft-tissue tumors of the hand. We reviewed clinical records and radiographs of 115 patients who had undergone operations for soft-tissue tumors or tumorous conditions of the hand. Bone changes were detected in the radiographs of 21 of the 115 patients. Giant cell tumor of tendon sheath was the most common histological type to be associated with bone changes. The most vulnerable part of the hand was the palmar side of the phalanx from the distal shaft to the head. Most of the bone changes were erosion with clear margins. The erosions tended to extend deeper into the bone with limited widening. "Steep deep" erosions were found in 5 patients; these erosions did not require reconstruction after surgical curettage, and tumors did not recur. PMID:22976605

Kitagawa, Yasuyuki; Tamai, Kensuke; Tsunoda, Ryu; Sawaizumi, Takuya; Takai, Shinro

2012-01-01

62

The Role of Vitamin D in the Bone Changes Associated with Simulated Weightlessness  

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The role of vitamin D in the change in bone metabolism was examined. The serum concentrations in rats sacrificed after 2, 5, 7, 10, 12 and 15 days of suspension was measured. Between days 1 and 5 of suspension and then gradually decreased towards normal between days 5 and 15. The time course of the changes in the circulating concentrations of 1,25(OH)2D and 24,25(OH)2D mirror almost precisely the changes in bone metabolism. The relationship between the changes in vitamin D metabolism and bone metabolism is investigated. Whether the bone changes are due to the change in serum concentration of 1,25(OH)2D or the changes in bone formation causing a reduction in Ca flux out of the serum pool and thereby suppressing 1,25(OH)2D production is examined. It is found that suspension had no effect on hormone concentration in the 1,25(OH)2D infused animals. Nevertheless, both vehicle and 1,25(OH)2D infused suspended rats exhibited the same reduction in bone mineral, and uptake of (45)Ca. It is suggested that the transitory reduction in circulating 1,25(OH)2D during suspension is not likely to cause the abnormalities in bone metabolism but rather that the changes in bone metabolism are primary and cause the fall in serum 1,25(OH)2D concentration. This supports the hypothesis that the metabolic abnormalities in bone associated with simulated weightlessness are due to the direct effect of unweighting on the bone.

Halloran, B. P.; Bikle, D. D.; Holton, E.; Levens, M. J.; Globus, R.

1985-01-01

63

Urinary deoxypyridinoline (DPD), serum bone glia protein (BGP) and bone metabolism change in hyperthyroidism  

International Nuclear Information System (INIS)

Objective: To study the effect of thyroid function on bone metabolism. Methods: Urinary DPD, Serum FT3, FT4 and BGP levels were determined with chemiluminescence assay and RIA in 41 patients with hyperthyroidism and 47 healthy controls. Results: Urinary DPD and serum FT3, FT4, BGP levels were significantly higher in patients with hyperthyroidism than those in healthy controls (p < 0.01). Conclusion: The data showed that hyperthyroidism was correlated with bone metabolism

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Glucocorticoid-Induced Changes in the Geometry of Osteoclast Resorption Cavities Affect Trabecular Bone Stiffness  

DEFF Research Database (Denmark)

Bone fracture risk can increase through bone microstructural changes observed in bone pathologies, such as glucocorticoid-induced osteoporosis. Resorption cavities present one of these microstructural aspects. We recently found that glucocorticoids (GCs) affect the shape of the resorption cavities. Specifically, we found that in the presence of GC osteoclasts (OCs) cultured on bone slices make more trenchlike cavities, compared to rather round cavities in the absence of GCs, while the total eroded surface remained constant. For this study, we hypothesized that trenchlike cavities affect bone strength differently compared to round cavities. To test this hypothesis, we cultured OCs on bone slices in the presence and absence of GC and quantified their dimensions. These data were used to model the effects of OC resorption cavities on bone mechanical properties using a validated beam-shell finite element model of trabecular bone. We demonstrated that a change in the geometry of resorption cavities is sufficient toaffect bone competence. After correcting for the increased EV/BV with GCs, the difference to the control condition was no longer significant, indicating that the GC-induced increase in EV/BV, which is closely related to the shape of the cavities, highly determines the stiffness effect. The lumbar spine was the anatomic site most affected by the GC-induced changes on the shape of the cavities. These findings might explain the clinical observation that the prevalence of vertebral fractures during GC treatment increases more than hip, forearm and other nonvertebral fractures.

Vanderoost, Jef; SØe, Kent

2012-01-01

65

Chargephilicity and chargephobicity: Two new reactivity indicators for external potential changes from density functional reactivity theory  

Science.gov (United States)

In analogy to the electrophilicity and the potentialphilicity, we define the chargephilicity and chargephobicity to describe the energetic response of a molecule to a change in its charge distribution. The chargephilicity captures the 'best' way to change the underlying charge distribution; the chargephobicity captures the 'worst' way to change the underlying charge distribution. The Coulomb potential induced by the linear-response function plays a very important role in this approach, analogous to the role of the hardness for the electrophilicity, the hardness kernel for the Fukui function, and the linear-response function for the potentialphilicity and potentialphobicity.

Ayers, Paul W.; Liu, Shubin; Li, Tonglei

2009-10-01

66

Bone turnover in passive smoking female rat: relationships to change in bone mineral density  

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Full Text Available Abstract Background Many studies have identified smoking as a risk factor for osteoporosis, but it is unclear whether passive smoking has an effect on bone mineral density and bone turnover and if such an effect could cause osteoporosis.The purpose of the study was to investigate the effect of passive smoking on bone mineral density (BMD and bone turnover and the relationship between BMD and bone turnover in female rat. Methods Forty-eight female Wistar rats were randomized into six groups: 2-month, 3-month,4-month smoke-exposed rats and their controls. A rat model of passive cigarette smoking was prepared by breeding female rats in a cigarette-smoking box for 2, 3 or 4 months. Serums were analyzed for levels of osteocalcin, bone-specific alkaline phosphatase (b-ALP and Tartrate-resistant acid phosphatase 5b (TRACP 5b. BMD was assessed at lumbar vertebrae and femur by dual energy X-ray absorptiometry in passive smoking rats and in control rats. Results BMD of lumbar spine and femur was lower in 4-month smoke-exposed female rats than that in controls. However, there was no significant difference in serum osteocalcin levels between smoke-exposed rats and controls. Significantly lower b-ALP and higher TRACP 5b were found in the 3-month or 4-month smoke-exposed rats compared to controls. Subsequent analysis showed that b-ALP positively correlated with BMD of the lumbar vertebrae(r = 0.764, P = 0.027 and femur(r = 0.899, P = 0.002 in 4-month smoke-exposed female rats. Furthermore, TRACP 5b levels negatively correlated with BMD of lumbar vertebrae (r = -0.871, P = 0.005 and femur (r = -0.715, P = 0.046 in 4-month smoke-exposed female rats. Conclusion Our data suggest that smoke exposure can inhibit bone formation and increase bone resorption. The hazardous effects of passive smoking on bone status are associated with increased bone turnover in female rat.

Xu Wen-shuo

2011-06-01

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A Comparative Effectiveness Study of Bone Density Changes in Women Over 40 Following Three Bone Health Plans Containing Variations of the Same Novel Plant-sourced Calcium  

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Background: The US Surgeon General's Report on Bone Health suggests America's bone-health is in jeopardy and issued a “call to action” to develop bone-health plans incorporating components of (1) improved nutrition, (2) increased health literacy, and (3) increased physical activity.Objective: To conduct a Comparative Effectiveness Research (CER) study comparing changes in bone mineral density in healthy women over-40 with above-average compliance when follo...

Gilbert R Kaats, Harry G. Preuss

2011-01-01

68

Changes observed in radionuclide bone scans during and after teriparatide treatment for osteoporosis  

Energy Technology Data Exchange (ETDEWEB)

Visual changes on radionuclide bone scans have been reported with teriparatide treatment. To assess this, serial studies were evaluated and quantified in ten postmenopausal women with osteoporosis treated with teriparatide (20 {mu}g/day subcutaneous) who had {sup 99m}Tc-methylene diphosphonate (MDP) bone scans (baseline, 3 and 18 months, then after 6 months off therapy). Women were injected with 600 MBq {sup 99m}Tc-MDP, and diagnostic bone scan images were assessed at 3.5 h. Additional whole-body scans (10 min, 1, 2, 3 and 4 h) were analysed for {sup 99m}Tc-MDP skeletal plasma clearance (K{sub bone}). Regional K{sub bone} differences were obtained for the whole skeleton and six regions (calvarium, mandible, spine, pelvis, upper and lower extremities). Bone turnover markers (BTM) were also measured. Most subjects showed visual changes on 3- and 18-month bone scan images that disappeared after 6 months off therapy. Enhanced uptake was seen predominantly in the calvarium and lower extremities. Whole skeleton K{sub bone} displayed a median increase of 22% (3 months, p = 0.004) and 34% (18 months, p = 0.002) decreasing to 0.7% (6 months off therapy). Calvarium K{sub bone} changes were three times larger than other sites. After 6 months off therapy, all K{sub bone} and BTM values returned towards baseline. The increased {sup 99m}Tc-MDP skeletal uptake with teriparatide indicated increased bone formation which was supported by BTM increases. After 6 months off therapy, metabolic activity diminished towards baseline. The modulation of {sup 99m}Tc-MDP skeletal uptake during treatment was the result of teriparatide's metabolic activity. These findings may aid the radiological evaluation of similar teriparatide patients having radionuclide bone scans. (orig.)

Moore, Amelia E.B.; Blake, Glen M.; Fogelman, Ignac [King' s College London, School of Medicine, Department of Nuclear Medicine, London (United Kingdom); Taylor, Kathleen A.; Ruff, Valerie A.; Rana, Asad E.; Wan, Xiaohai [Eli Lilly and Company, Indianapolis, IN (United States)

2012-02-15

69

Physical bone changes in carragheenin-induced arthritis evaluated by quantitative computed tomography  

International Nuclear Information System (INIS)

Repeated non-invasive measurements were performed in dogs to trabecular bone density (TBD), low density bone area (LDBA), and high density bone area (HDBA) in chronic arthritis using quantitative computed tomography (QCT). Unilateral chronic arthritis of the knee had been induced by weekly instillation of 2 ml carragheenin into the right knee joint for 12 weeks with the left knee serving as a control. CT scanning of the distal femoral condyles was performed in 12 mature dogs with chronic arthritis. Another 6 dogs underwent a longitudinal CT study starting immediately prior to induction of arthritis. Indentation test and histomorphometric analyses confirmed the bone density changes as measured by CT. (orig./GDG)

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Longitudinal changes in the height and location of bone bridge from autogenous iliac bone graft in patients with cleft lip and palate  

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Full Text Available Background: Secondary alveolar bone graft has been widely used for the closure of maxillary bone defects in patients with cleft lip and palate (CLP. However, the log-term stability of grafted bone in detail remains unclear. Purpose: To evaluate the nature of longitudinal changes in the grafted bone from autogenous iliac bone in patients with CLP for more than 2 years after the surgery. Methods and Subjects: The subjects were 124 CLP patients treated with iliac bone graft in Hiroshima University Hospital from 1997 to 2007. The height and location of the bone bridge was evaluated radiographically before and after surgery. Results: 1 Bone graft was performed at a mean age of 12.5 (±4.2 years old. The canines on the cleft side were not erupted at the surgery in 60.0%. All canines erupted except for the congenital missing and impacted ones (11.3% within 2 years after bone graft; 2 The height of the bone bridge was more than 11 mm in 71.8% of all patients 1 month after surgery. In addition, the location of bone bridge in 66.1% of all patients were clinically satisfactory. However, these rates decreased time-dependently owing to bone resorption after the bone graft. Conclusions: In conclusion, it is shown that autogenous bone graft produce a sufficient bone bridge in the jaw cleft area by the long-term evaluation of the changes in height and location of bone bridge, although some amount of time-dependent bone resorption is inevitable.

Nobuhiko Kawai

2013-03-01

71

Changes in total body bone mineral density following a common bone health plan with two versions of a unique bone health supplement: a comparative effectiveness research study  

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Full Text Available Abstract Background The US Surgeon General's Report on Bone Health suggests America's bone-health is in jeopardy and issued a "call to action" to develop bone-health plans that: (1 improve nutrition, (2 increase health literacy and, (3 increase physical activity. This study is a response to this call to action. Methods After signing an informed consent, 158 adults agreed to follow an open-label bone-health plan for six months after taking a DXA test of bone density, a 43-chemistry blood test panel and a quality of life inventory (AlgaeCal 1. Two weeks after the last subject completed, a second group of 58 was enrolled and followed the identical plan, but with a different bone-health supplement (AlgaeCal 2. Results There were no significant differences between the two groups in baseline bone mineral density (BMD or in variables related to BMD (age, sex, weight, percent body fat, fat mass, or fat-free mass. In both groups, no significant differences in BMD or related variables were found between volunteers and non-volunteers or between those who completed per protocol and those who were lost to attrition. Both groups experienced a significant positive mean annualized percent change (MAPC in BMD compared to expectation [AlgaeCal 1: 1.15%, p = 0.001; AlgaeCal 2: 2.79%, p = 0.001]. Both groups experienced a positive MAPC compared to baseline, but only AlgaeCal 2 experienced a significant change [AlgaeCal 1: 0.48%, p = 0.14; AlgaeCal 2: 2.18%, p p = 0.005. The MAPC contrast between compliant and partially compliant subjects was significant for both plans (p = 0.001 and p = 0.003 respectively. No clinically significant changes in a 43-panel blood chemistry test were found nor were there any changes in self-reported quality of life in either group. Conclusions Following The Plan for six months with either version of the bone health supplement was associated with significant increases in BMD as compared to expected and, in AlgaeCal 2, the increase from baseline was significantly greater than the increase from baseline in AlgaeCal 1. Increased compliance was associated with greater increases in BMD in both groups. No adverse effects were reported in either group. Trial Registration ClinicalTrials.gov NCT01114685

Dapilmoto Monika

2011-04-01

72

Changes in reactivity by insertion of water in the internal graphite reflector of the Argonaut reactor  

International Nuclear Information System (INIS)

The internal graphite reflector of the SAR-annular core was replaced by 1500 graphite spheres of the AVR moderator type (60 mm diameter) and the thereby arised gap volumes was filled up by water (styropen and polyethylene particles). The water density was adjusted new for each experiment, because there were found reactivity changes against the normal pebble-bed arrangement. The maximum of the reactivity is near 3.6 vol.% water showing the improvement of the neutron moderation and reflection. By further increase of the water density the reactivity dropped continuously to the experimental adjusted value of 35 vol.% water caused by the predominated neutron absorption. (Auth.)

73

Effects of adrenalectomy and glucocorticosteroid therapy on bone marrow T cells. Effect on T cell traffic and graft-versus-host (GVH) reactivity  

International Nuclear Information System (INIS)

The effects of bilateral adrenalectomy (Ax) and glucocorticosteroid (GCS) treatment on the migratory behavior of circulating T cells in mice were evaluated by a 51Cr lymphocyte migration assay and two graft-versus-host (GVH) assays. The major new findings were that bilaterally adrenalectomizing a mouse effects it in two interrelated ways: 1) It decreases the accumulation of adoptively transferred 51Cr-labeled T cells to the bone marrow; and 2) it reduces the GVH reactivity of bone marrow cells. We also confirmed previous studies showing increases in the accumulation of T cells and increases in T cell-mediated GVH reactivity in the marrow of GCS-treated mice. We conclude that Ax has an opposite effect to that of GCS treatment on the intramarrow traffic of T cells and on T cell-mediated GVH reactivity of marrow cells

74

Treatment of Radiation Induced Biological Changes by Bone Marrow Transplantation  

International Nuclear Information System (INIS)

Preventing the propagation of radiation induced oxidative damage has been a subject of considerable investigations. The ultimate goal of the present study is to use bone marrow cells to ameliorate or to treat the radiation sickness. Transplantation of bone marrow cell has shown promising results in the present experimental radiation treatment. In this report, suspension of bone marrow cells was injected into rats 12 h. after exposure to 4.5 Gy whole body gamma irradiation. Significant results were recorded on the successful control of the radiation induced disorders in a number of biochemical parameters including certain enzymatic and nonenzymatic antioxidants (superoxide dismutase and glutathione) and certain parameters related to kidney function including creatinine, urea as well as Atpase Activity in blood serum, urine and kidney tissue

75

Bone marrow changes on STIR MR images of asymptomatic feet and ankles  

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The purpose of this study was to evaluate the prevalence, pattern and size of bone marrow changes on short-tau inversion recovery (STIR) magnetic resonance (MR) images of asymptomatic feet and ankles. In 78 asymptomatic volunteers (41 women, 37 men; median age 47 years; range 23-83 years) sagittal STIR MR images of hindfoot and midfoot were reviewed for various patterns of high signal changes in bone marrow. The size of these bone marrow changes was measured, and signal intensity was rated semi-quantitatively using a scale from 0 (=normal) to 10 (=fluid-like). Fifty percent (39/78) of all volunteers had at least one bone marrow change. Thirty-six percent (28/78) of all volunteers had edema-like changes, 26% (20/78) had necrosis-like changes, and 5% (4/78) had cyst-like changes. The long diameters of all changes varied between 4 mm and 16 mm (median 7.5 mm). The median signal intensity for all changes was 5.0 (range 1-10). Bone marrow changes on STIR MR images are commonly detected in asymptomatic feet and ankles. However, such changes tend to be small (<1 cm) or subtle. (orig.)

Zubler, Veronika; Mengiardi, Bernard; Pfirrmann, Christian W.A.; Duc, Sylvain R.; Schmid, Marius R.; Hodler, Juerg; Zanetti, Marco [University Hospital, Balgrist, Department of Radiology, Zurich (Switzerland)

2007-12-15

76

Reactivation of Immunological Response in Lethally X-Irradiated Mice Treated with Isogeneic Bone Marrow  

International Nuclear Information System (INIS)

Male and female C57BL/H and CBA/H mice aged 10-12 weeks were used as recipients and donors, respectively. All recipient mice were given a lethal whole-body X-irradiation dose (850 R for C57BL and 950 R for CBA mice) followed by iv injection of 10 x 106 isogeneic eosin-negative bone-marrow cells suspended in 0.5 ml of Hank's solution. The number of eosin-positive cells was less than 10%. The state of immunological responsiveness of irradiated recipients was measured at different time intervals up to 86 days after irradiation. The immune response to bacterial antigen was measured with the titre of agglutinating antibodies in serum six days after iv antigenic stimulation with a suspension of 2 x 107 killed Salmonella typhimurium cells. The immune response to tissue antigens was evaluated by: (a) the effectiveness of the spleen cells from isologous radiation chimeric parental mice in preventing bone marrow from F1 (C57BL x CBA) hybrid donor from therapeutically affecting lethally irradiated F j recipient mice; (b) the effectiveness of the spleen cells in inducing splenom egaly in recipient F1 hybrid mice (Simonsen test). It was found that the responsiveness to bacterial antigens reappears much earlier and increases much faster than the immunological responsiveness to tissue antigens. (author)

77

Radiographic bone changes in multibacillary leprosy patients in Aburof mission clinic  

International Nuclear Information System (INIS)

Leprosy is an infectious, chronic granulomatous disease, caused by M. leprae. It is one of the most seriously disabling and economically important disease. In Sudan it affects about 20 thousands people. In this study 60 patients of MB leprosy were included. Historry and physical examination were carried out for each patient. BI was done for all patients and were subjected to x-ray investigations of the paranasal sinuses, hands and feet. 85%(51) of these patients were found to have radiographic changes in paranasal sinuses, 35 patients with mucosal thickening and 16 with diffuse opacified sinuses. 86.7% (52) of those patients were found to have radiographic bone changes in their hand and feet. 23.6% and 75.4% were found with specific and non-specific bone changes in their hands and feet respectively. A spectrum of radiographic bone changes was found in the hands and feet including; destruction, fractures, phalangeal resoption, distal phalangeal tapering, flexion deformities, osteoarthritic changes, charcot's joints, osteoporosis cystic bone changes and enlarged nutrient bone foramina. The majority of patients with radiographic changes in the paranasal sinsuses, hands and feet, were found to have long duration of the disease and more bacterial load. The disability in hands and feet is the major risk factor in bone affection in MB leprosy. (Author)

78

Osseous changes in the foot bones in patients with arterial occlusion and simultaneous polyneuropathy  

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The present article evaluates 26 cases with arterial occlusion and additional polyneuropathy in diabetes mellitus or chronic alcohol addiction. For comparison, a group of 30 patients with arterial occlusion without neutrologically detectable polyneuropathy were also evaluated. It is pointed out that the osseous changes in the foot bone region are due to the additionally existing polyneuropathy and cannot be explained alone by an avascular bone necrosis in arterial vascular occlusion. Changes in the sense of an arthropathy occur in our group of patients even in case of unilateral arterial occlusion, these changes occurring bilaterally in the foot bones; after reconstruction measures in the arterial vascular system, these arthropathic changes in the foot bones continue to advance in case of persisting polyneuropathy.

Langer, R.; Langer, M.

1981-09-01

79

Osseous changes in the foot bones in patients with arterial occlusion and simultaneous polyneuropathy  

International Nuclear Information System (INIS)

The present article evaluates 26 cases with arterial occlusion and additional polyneuropathy in diabetes mellitus or chronic alcohol addiction. For comparison, a group of 30 patients with arterial occlusion without neutrologically detectable polyneuropathy were also evaluated. It is pointed out that the osseous changes in the foot bone region are due to the additionally existing polyneuropathy and cannot be explained alone by an avascular bone necrosis in arterial vascular occlusion. Changes in the sense of an arthropathy occur in our group of patients even in case of unilateral arterial occlusion, these changes occurring bilaterally in the foot bones; after reconstruction measures in the arterial vascular system, these arthropathic changes in the foot bones continue to advance in case of persisting polyneuropathy. (orig.)

80

Investigation of dynamic of reactivity steam ratio changes for RBMK-1000 reactor fuel cell  

International Nuclear Information System (INIS)

The paper presents investigation of dynamic of reactivity steam ratio (RSR) changes for RBMK-1000 using computer code WIMSD-5B. Comparison of calculating results and experimental data for Chernobyl NPP was carried out. It is confirmed by calculating that RSR became positive one at the end of campaign. It is shown that increasing of fuel concentration improves dynamic of RSR changes

 
 
 
 
81

The Role of Nutrition in the Changes in Bone and Calcium Metabolism During Space Flight  

Science.gov (United States)

On Earth, the primary purpose of the skeleton is provide structural support for the body. In space, the support function of the skeleton is reduced since, without gravity, structures have only mass and no weight. The adaptation to space flight is manifested by shifts in mineral distribution, altered bone turnover, and regional mineral deficits in weight-bearing bones. The shifts in mineral distribution appear to be related to the cephalic fluid shift. The redistribution of mineral from one bone to another or to and from areas in the same bone in response to alterations in gravitational loads is more likely to affect skeletal function than quantitative whole body losses and gains. The changes in bone turnover appear dependent upon changes in body weight with weight loss tending to increase bone resorption as well as decrease bone formation. During bedrest, the bone response to unloading varies depending upon the routine activity level of the subjects with more active subjects showing a greater suppression of bone formation in the iliac crest with inactivity. Changes in body composition during space flight are predicted by bedrest studies on Earth which show loss of lean body mass and increase tn body fat in adult males after one month. In ambulatory studies on Earth, exercising adult males of the same age, height, g weight, body mass index, and shoe size show significantly higher whole body mineral and lean body mass. than non-exercising subjects. Nutritional preference appears to change with activity level. Diet histories in exercisers and nonexercisers who maintain identical body weights show no differences in nutrients except for slightly higher carbohydrate intake in the exercisers. The absence of differences in dietary calcium in men with higher total body calcium is noteworthy. In this situation, the increased bone mineral content was facilitated by the calcium endocrine system. This regulatory system can be by-passed by raising dietary calcium. Increased calcium intake can increase the calcium content in normally loaded bone. However, bone with a higher calcium content still decreases proportionally to normal bone during unloading. Nutritional requirements in space should be reevaluated with respect to these adaptive changes to loading and physical activity.

Morey-Holton, Emily R.; Arnaud, Sara B.

1995-01-01

82

Image registration of proximal femur with substantial bone changes: application in 3D visualization of bone loss of astronauts after long-duration spaceflight  

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We recently studied bone loss in crewmembers making 4 to 6 months flights on the International Space Station. We employed Quantitative Computed Tomography (QCT) technology (Lang et. al., J Bone Miner Res. 2004; v. 19, p. 1006), which made measurements of both cortical and trabecular bone loss that could not be obtained by using 2-dimensional dual x-ray absorptiometry (DXA) imaging technology. To further investigate the bone loss after spaceflight, we have developed image registration technologies to align serial scans so that bone changes can be directly visualized in a subregional level, which can provide more detailed information for understanding bone physiology during long-term spaceflight. To achieve effective and robust registration when large bone changes exist, we have developed technical adaptations to standard registration methods. Our automated image registration is mutual-information based. We have applied an automatically adaptive binning method in calculating the mutual information. After the pre- and post-flight scans are geometrically aligned, the interior bone changes can be clearly visualized. Image registration can also be applied to Finite Element Modeling (FEM) to compare bone strength change, where consistent loading conditions must be applied to serial scans.

Li, Wenjun; Sode, Miki; Saeed, Isra; Lang, Thomas

2006-03-01

83

Changes in spinal and femoral bone mineral density due to pelvic irradiation following oophorectomy  

International Nuclear Information System (INIS)

Since radiation therapy has been known to be a cause of bone atrophy (radiation osteopathy), it could be important whether postoperative radiotherapy in patients who have undergone oophorectomy further promotes bone mineral loss or not. Nineteen patients with stage Ib to IIb cervical cancer were studied. Eleven of the 19 patients received only surgical treatment and 8 received postoperative radiotherapy (50 Gy to the pelvis and 40 Gy to the lumber spine), because of the presence of advanced lesions or positive lymphnodes. A significant increase in FSH and decrease in E2 (p<0.01) compared to before treatment were observed in both groups. A significant increase in serum alkaline phosphatase activities (p<0.01), urine-calcium/creatinine ratio (p<0.05) and urine-hydroxyproline/creatinine ratio (p<0.01), which indicated high bone turnover, compared to before treatment in both groups also appeared. Although these chemical parameters in both groups changed coincidentally, the decline in spinal bone mineral density in the irradiated group was delayed at 12 months after the treatment. On the other hand, there was no difference in the changes in femoral bone mineral density in the two groups. These results suggest that radiotherapy might inhibit the bone mineral loss at the irradiated bone site even when there was an estrogen lack. (author)

84

Comparative changes of morphology and lectin histochemistry characteristics of parathyroid glands and bone tissue.  

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Full Text Available The aim of the study was comparative analysis of guinea pig and human bone tissue due to postnatal changes of parathyroid glands morphology. The object of research were structural elements and cellular carbohydrate determinants of parathyroid glands and bone tissue with comparative characteristics of mineral exchange and parathyroid hormone levels. Were used morphometric, histochemistry, lectin histochemistry, biochemistry and immunology metods. Age- and sex-related morpho-functional and lectin histochemical peculiarities of parathyroid glands and bone tissue were investigated during postnatal ontogenesis in human and guinea pig. Correlations between DNA/RNA contents, nuclear volume of parathyrocytes, blood parathormone level with respect to Ca-, P-, and Mg- content in blood serum and bone tissue were estimated. We detected significant reduction of the width cortical layer and osseous trabecules, increased iliac bone mineralization, with simultaneous enhancement of nuclear volume and DNA/RNA content of parathyrocytes in females of groups III (aged 60-74 and IV (aged 75-90. We revealed age-related changes in lectin binding to cellular and stromal elements of parathyroid glands and bone tissue. The data extend our knowledge on the histochemical peculiarities of parathyroid glands and bone tissue during postnatal ontogenesis and under hyperparathyroidism, demonstrate possibilities of lectin application for selective labelling of chondrocytes, osteoblasts, osteocytes and osteoclasts.

Dzhura O.R.

2007-01-01

85

Ultrastructural changes of bone marrow cells exposed for xenogenous cerebrospinal fluid  

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Full Text Available Due to the scientifical investigations xenogenous cerebrospinal fluid was considered as possible substance for theproduction of powerful adaptogen of biological origin. One of the representative research in these field demonstrates morphologicaland functional changes of bone marrow as the central hemopoetic and immune organ. The article shows the ultramicroscopicchanges of bone marrow cells after the xenogenous cerebrospinal fluid exposure in Vistar rats of differentage. It was revealed the activation of synthetic processes in bone marrow cells of the first three age groups and exhaustion ofactivating mechanisms in the fourth age group, that was manifested in swelling and destruction of mytochondria, vacuolisationof cytoplasm, invagination of caryolemma.

Shaymardanova L.R.

2010-01-01

86

Ossificans myositis: inflammatory changes and contrast enhancement of adjacent bone shown by MR imaging  

International Nuclear Information System (INIS)

The authors report a case of ossificans myositis, in which magnetic resonance imaging (MRI) showed inflammatory changes of the adjacent bone. T 1 weighted fat saturation sequence with gadolinium injection showed enhancement of medullary and cortical bone. This potentially mistaking pattern must be known, to avoid mis diagnosing with malignant osseous tumor, specially before achievement of the characteristic pattern of zonal maturation and its calcified rim. (authors). 15 refs., 6 figs

87

Temperature change in pig rib bone during implant site preparation by low-speed drilling  

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OBJECTIVES: The purpose of this study was to evaluate the temperature change during low-speed drilling using infrared thermography. MATERIAL AND METHODS: Pig ribs were used to provide cortical bone of a similar quality to human mandible. Heat production by three implant drill systems (two conventional drilling systems and one low-speed drilling system) was evaluated by measuring the bone temperature using infrared thermography. Each system had two different bur sizes. The drill systems used w...

Sun-Jong Kim; Jaeyoung Yoo; Young-Soo Kim; Sang-Wan Shin

2010-01-01

88

Paleopathological analysis of changes on animal bones originating from archaeological sites Caricin Grad and Studenica Monastery  

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Full Text Available This work presents the estimation of incidence and analysis of paleopathological changes on skeletal remains of the animals from archaeological sites Caricin Grad and Studenica Monastery. Moreover, there has been carried out the assessment of the skeletal elements, as well as taxonomic and age determination. The total of 2595 bones or bone fragments were examined. In 22 specimens there were noticed various abnormal skeletal changes in following animal species: cattle, sheep, goats, pigs, horses, donkeys and camels. Pathological changes were noticed on the teeth, mandibles, joints of long bones and phalanxes. By macroscopic analysis of these acquired pathological changes on bones of the animals, there was determined that the observed lesions had had proliferative, hypertrophic and chronic character. Proliferative changes on the bones of the cattle, horses, donkeys and camels point out to the fact that these animals were used for towing and/or load carrying. Identified diseases of oral cavity in small ruminants point out to improper and inadequate nutrition of these animals in the past.

Markovi? Nemanja

2014-01-01

89

Pore structure and reactivity changes in hot coal gas desulfurization sorbents  

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The primary objective of the project was the investigation of the pore structure and reactivity changes occurring in metal/metal oxide sorbents used for desulfurization of hot coal gas during sulfidation and regeneration, with particular emphasis placed on the effects of these changes on the sorptive capacity and efficiency of the sorbents. Commercially available zinc oxide sorbents were used as model solids in our experimental investigation of the sulfidation and regeneration processes.

Sotirchos, S.V.

1991-05-01

90

Measurements of bone cements implanted into rats using high-resolution X-ray CT. Time-dependency of form and volume change in bone cement  

International Nuclear Information System (INIS)

A micro-focus X-ray CT has been used for imaging the inner volume change of bone cement implanted into the body of a small animal in living condition. 3-D precise images of the bone cement materials, implanted into the thigh bones of rats, were obtained intermittently for one year using the CT system. The time-dependent 3-D form and volume changes of the bone cement were measured for the same rat continuously. During one year from implantation, the form of the implanted bone cement changed and a significant volume decrease was observed. It was shown that micro-focus X-ray CT was very effective for imaging in bio-research. (author)

91

Changes of the immune reactivities of antibodies produced against gamma-irradiated antigen  

International Nuclear Information System (INIS)

To observe the changes of immunogenicity and antigenicity of gamma-irradiated ovalbumin (OVA), an antigen (Ag) solution (2.0 mg/ml) was prepared and irradiated with the absorbed doses of 3 and 10 kGy. Immunoglobulin G (IgG) was produced for each Ag. 0, 3 and 10 kGy-IgG were individually reacted against 3 Ags in an ELISA cross reactivity test. Cross reactivity of each IgG was significantly different for each Ag. Especially the 10 kGy-irradiated OVA lost most antigenicity compared to the 0 kGy-IgG

92

Investigation of reactivity change and neutron noise due to random absorber vibrations. 1  

International Nuclear Information System (INIS)

Perturbations of the neutron flux due to stochastically excited vibrations of absorbers have been investigated with the aid of a one-dimensional core model with N pointlike absorbers. It is shown that the increase of absorber efficiency due to vibrations may be understood as the spatial analog to the Doppler broadening and can be taken into account by appropriate corrections of the Galanin constants of the absorbers. The reactivity change can be estimated by means of reactivity coefficients and the r.m.s. values of the absorber vibrations. (author)

93

On the estimation of a small reactivity change in critical reactors by Kalman filtering technique  

International Nuclear Information System (INIS)

In the present paper we critically review the bank of Kalman filters method for reactivity estimation originally suggested by D'Attellis and Cortina. It is pointed out that the procedure cannot be applied reliably in the form proposed by the authors, because of the invalid interpretation of the decision rule as well as the presence of the filter divergence. An improved method based on D'Attellis' and Cortina's idea, free from divergence problems, is presented. The procedure is applied to the estimation of small reactivity changes occurring after a long critical operation of the reactor. (Author)

94

Desferrioxamine-induced long bone changes in thalassaemic patients - Radiographic features, prevalence and relations with growth  

Energy Technology Data Exchange (ETDEWEB)

AIM: To study the radiographic findings of desferrioxamine-induced bone dysplasia, its prevalence and relation to growth in thalassaemic patients. MATERIALS AND METHODS: A cross-sectional study was performed in 35 thalassaemic patients on a hypertransfusion scheme and chelation therapy at a dose not exceeding 50 mg/kg/day. Radiographs of the left hand taken for bone age assessment in consecutive patients over the past 12 months were evaluated for signs of desferrioxamine-induced bone dysplasia. The findings were correlated with data on growth, chelation and body iron content. RESULTS: Twelve of 35 patients had evidence of desferrioxamine-induced long bone dysplasia. There was no significant difference in the groups with and without radiographic evidence of bone dysplasia with respect to the height percentile at time of initiation of therapy, height percentile at time of radiography, skeletal age delay, age at starting chelation, chelation dose and duration, units of blood transfused, average chelation dose, and serum ferritin levels at time of radiography. Both groups showed a reduced percentile growth with a significantly greater reduction (P = 0.03) in the patients with dysplastic change. CONCLUSION: Desferrioxamine-induced bone dysplasia is associated with height reduction and can be seen in patients receiving desferrioxamine chelation therapy at doses of less than 50 mg/kg/day. Awareness of the diagnosis is of importance as reduction of the desferrioxamine dose may improve bone growth. Chan, Y. L. (2000)

Chan, Y.L.; Li, C.K.; Pang, L.M.; Chik, K.W

2000-08-01

95

Changes in attentional processing and affective reactivity in pregnancy and postpartum  

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Full Text Available Jackie K Gollan, Laina Rosebrock, Denada Hoxha, Katherine L Wisner Asher Center for the Study and Treatment of Depressive Disorders, Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA Abstract: The aim of this review is to provide an overview of the research in attentional processing and affective reactivity in pregnancy and postpartum to inform future research. Numerous changes occur in attentional processing and affective reactivity across the childbearing period. This review focuses on the definition and methods of measuring attentional processing and affective reactivity. We discuss research studies that have examined the changes in these two processes during the perinatal phases of pregnancy and postpartum, with and without depression and anxiety. We evaluate the importance of using multiple levels of measurement, including physiological and neuroimaging techniques, to study these processes via implicit and explicit tasks. Research that has identified regions of brain activation using functional magnetic resonance imaging as well as other physiological assessments is integrated into the discussion. The importance of using sophisticated methodological techniques in future studies, such as multiple mediation models, for the purpose of elucidating mechanisms of change during these processes in pregnancy and postpartum is emphasized. We conclude with a discussion of the effect of these processes on maternal psychological functioning and infant outcomes. These processes support a strategy for individualizing treatment for pregnant and postpartum women suffering from depression and anxiety. Keywords: attentional processing, emotion, affective reactivity, depression, pregnancy, postpartum

Gollan JK

2014-11-01

96

RA reactor reactivity changes before refurbishment - Task 3.08/02  

International Nuclear Information System (INIS)

From the the end of 1959, when the RA reactor started operation until January 1963 reactor was operated with the initial fuel batch of 56 fuel channels. After 310 MWd 68 fuel channels were added to the reactor core, and after further 357 MWd the core was filled up to the maximum of 88 fuel channels. Basic reactor parameters were systematically measured during two years of operation. This report covers the measurements concerned directly with the reactor operation: calibration of the control rods and their reactivity worths during operation, determining the total built-in reactivity excess and its change during burnup, determination of reactivity dependence on the temperature, xenon effect in the core

97

Clinical study of bone changes after parathyroidectomy among patients maintained by hemodialysis  

International Nuclear Information System (INIS)

Thirteen patients maintained by hemodialysis with secondary hyperparathyroidism were mainly studied using Tc 99m-MDP bone scintigraphy and lamina dura index (LDI) which was judged by dental films. After parathyroidectomy (PTX), the most prominent change appeared on the calvaria, maxilla, and mandible in scintigrams. Intensity of Tc 99m-MDP accumulation was represented by using a quantitative method of bone-to-soft tissue uptake ratio (4 hr-B/St ratio). 4 hr-B/St ratio gradually decreased and became normal within one and a half years after PTX. The accumulation of Tc 99m-MDP on the calvaria may reveal the status of bone metabolism in the patients with secondary hyperparathyroidism. Also, LDIes gradually decreased during 4 through 6 months after PTX. However it was considered that these indexes might need a long term to return to normal range. We couldn't differenciate which method was superior in the diagnostic value for detecting early skeletal changes between roentogenograms and bone scintigraphy as a indicator of post-PTX bone improvement. However, bone scintigraphy should be added to conventional examinations for following the courses of patients that underwent PTX because this procedure has many other advantages. (author)

98

Differential age-related bone architecture changes between female and male STR/Ort mice.  

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The incidence of spontaneous osteoarthritis (OA) in female STR/Ort mice is much lower than that observed in male STR/Ort mice; however, the reason for the differential incidence of OA between sexes has not been elucidated. Here, we investigated and compared age- and sex-related bone mineral density and architectural changes in male and female STR/Ort mice. Bone architecture and bone mineral density (BMD) of femurs were examined in 5-, 10-, 15-, 20-, and 35-week-old male and female STR/Ort mice by microscopic computed tomography (µCT). Angular degrees of internal tibial torsion (ADITT) were also measured in mice at 5, 15, and 35 weeks of age. Earlier decreases of cancellous volume and BMD were found in male STR/Ort mice. Using µCT, an age-related decline of bone marrow space in femoral diaphysis was observed in both males and females but was more dramatic in females. In addition, an earlier increase of ADITT was observed in male STR/Ort mice, suggesting that internal rotation of the tibia may contribute to OA. Age- and sex-related bone architectural changes clearly differ between male and female STR/Ort mice. These differences in bone structure, particularly ADITT, may explain the differential incidence of OA in STR/Ort mice. PMID:22293673

Uchida, Kentaro; Urabe, Ken; Naruse, Kouji; Kozai, Yusuke; Onuma, Kenji; Mikuni-Takagaki, Yuko; Kashima, Isamu; Ueno, Masaki; Sakai, Rina; Itoman, Moritoshi; Takaso, Masashi

2012-01-01

99

Tumor-induced osteoclast miRNA changes as regulators and biomarkers of osteolytic bone metastasis.  

Science.gov (United States)

Understanding the mechanism by which tumor cells influence osteoclast differentiation is crucial for improving treatment of osteolytic metastasis. Here, we report broad microRNA (miRNA) expression changes in differentiating osteoclasts after exposure to tumor-conditioned media, in part through activation of NF?B signaling by soluble intracellular adhesion molecule (sICAM1) secreted from bone-metastatic cancer cells. Ectopic expression of multiple miRNAs downregulated during osteoclastogenesis suppresses osteoclast differentiation by targeting important osteoclast genes. Intravenous delivery of these miRNAs in vivo inhibits osteoclast activity and reduces osteolytic bone metastasis. Importantly, serum levels of sICAM1 and two osteoclast miRNAs, miR-16 and miR-378, which are elevated in osteoclast differentiation, correlate with bone metastasis burden. These findings establish miRNAs as potential therapeutic targets and clinical biomarkers of bone metastasis. PMID:24135284

Ell, Brian; Mercatali, Laura; Ibrahim, Toni; Campbell, Neil; Schwarzenbach, Heidi; Pantel, Klaus; Amadori, Dino; Kang, Yibin

2013-10-14

100

Reactivating memories during sleep by odors: odor specificity and associated changes in sleep oscillations.  

Science.gov (United States)

Memories are reactivated during sleep. Re-exposure to olfactory cues during sleep triggers this reactivation and improves later recall performance. Here, we tested if the effects of odor-induced memory reactivations are odor-specific, that is, requiring the same odor during learning and subsequent sleep. We also tested whether odor-induced memory reactivation affects oscillatory EEG activity during sleep, as a putative mechanism underlying memory processing during sleep. Participants learned a visuospatial memory task under the presence of an odor. During subsequent SWS, the same odor, a different odor, or an odorless vehicle was presented. We found that odor re-exposure during sleep significantly improves memory only when the same odor was presented again, whereas exposure to a new odor or the odorless vehicle had no effect. The memory-enhancing effect of the congruent odor was accompanied by significant increases in frontal delta (1.5-4.5 Hz) and parietal fast spindle (13.0-15.0 Hz) power as well as by an increased negative-to-positive slope of the frontal slow oscillation. Our results indicate that odor-induced memory reactivations are odor specific and trigger changes in slow-wave and spindle power possibly reflecting a bottom-up influence of hippocampal memory replay on cortical slow oscillations as well as thalamo-cortical sleep spindles. PMID:24456392

Rihm, Julia S; Diekelmann, Susanne; Born, Jan; Rasch, Björn

2014-08-01

 
 
 
 
101

The biochemical changes of bone collagen after high-dose irradiation  

International Nuclear Information System (INIS)

In our clinic, patients with malignant bone tumors have been treated by high-dose irradiation therapy, 10,000-20,000 rads, for primary lesions. In order to study the biochemical changes of normal bone around tumor tissue, especially bone collagen, after high-dose irradiation, the author performed the following experiments. The right knee joint of rabbits was irradiated with either 6,000, 10,000, or 15,000 rads by 60Co-? ray. The cortical bone of the right tibial metaphysis was used for analyses and compared with the left tibia of the same rabbit. These studies were followed for one year after the final irradiation. The calcium, phosphorous and collagen contents of irradiated bone were remarkably changed. These data indicate that collagen biosynthesis of irradiated bone was decreased and the calcification was disturbed. An increase in the amount of total soluble collagen and a decrease in the amount of hydroxylysine bound sugar were observed. The ratio of ? to ? chains of the collagen molecule was also changed by the irradiation. The amount of reducible cross-links per hydroxyproline residue was strikingly increased three months after the final irradiation. These changes were remarkable especially in the 10,000 and 15,000 rads irradiated group and found to be recovered approximately six months to one year after the final irradiation. These findings indicate that high-dose irradiation reduces the stability of bone collagen both with the destruction of sugar bonds of hydroxylysine residues and the replacement of matured collagen matrix to immatured one which contain mostly labile reducible cross-links. (author)

102

Changes in the viscoelastic properties of cortical bone by selective degradation of matrix protein.  

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We have studied stress relaxation of bovine femoral cortical bone specimens treated with KOH aqueous solution which had been known to degrade selectively protein molecules in bone. With the KOH treatment, we found an increase in specimens' volume. This increase was regarded as swelling of the bone specimen, presumably due to matrix protein network degradation including that of collagen. In an analogy of bone to gel structure, an increasing ratio of specimen volume was used as an indicating parameter for the matrix protein network degradation by the treatment. Although an empirical equation with a linearly combined form of two Kohlrausch-Williams-Watts (KWW) functions has been shown to describe the stress relaxation of bone specimens, a single KWW function was suitable for the bone specimens treated with KOH solution for as little as 3h. In KOH treated specimens, both the initial modulus and the relaxation time decreased with the volume-increasing ratio, while the relaxation time distribution did not change. A chemo-rheological consideration attributed the reduction of modulus values to the network degradation in the organic matrix phase. The relaxation time of KOH treated specimens was thought to be related to the longer relaxation time of untreated bones, although there was a discontinuity between the extrapolated relaxation time values for KOH treated specimens and untreated specimens. This discontinuity may have originated from the release of residual stress existing in the bone by the matrix protein degradation. The results of the present study suggest that the state of matrix protein is crucial for integrating the mechanical properties of bone. PMID:23261016

Shirakawa, Hideki; Furusawa, Kazuya; Fukui, Akimasa; Tadano, Shigeru; Sasaki, Naoki

2013-02-22

103

Postirradiation atrophic changes of bone and related complications  

International Nuclear Information System (INIS)

The sequence of radiographically visible changes about the shoulder girdle following irradiation was analyzed in 49 patients who received 200 kV irradiation, in 50 who received 25 MeV betatron photon irradiation, and in 20 who received cobalt-60 ? irradiation. The changes were dose related and were most evident in the kilovoltage group, but also occurred following megavoltage therapy. Atrophic changes may be complicated by fracture, true necrosis, true osteitis, or sarcoma. These atrophic changes have clinical significance similar to the atrophic changes that occur in skin and mucous membranes. The terms radionecrosis and radiation osteitis as applied to these changes should be abandoned since they imply a more serious process than is actually present. Biopsy should be avoided if possible since trauma and secondary infection could lead to true necrosis

104

Morphological Change of Heat Treated Bovine Bone: A Comparative Study  

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Full Text Available In this work, untreated bovine cortical bones (BCBs were exposed to a range of heat treatments in order to determine at which temperature the apatite develops an optimum morphology comprising porous nano hydroxyapatite (nanoHAp crystals. Rectangular specimens (10 mm × 10 mm × 3–5 mm of BCB were prepared, being excised in normal to longitudinal and transverse directions. Specimens were sintered at up to 900 °C under ambient pressure in order to produce apatites by two steps sintering. The samples were characterized by thermogravimetric analysis, X-ray diffraction (XRD, and scanning electron microscopy (SEM attached to an energy-dispersive X-ray spectroscopy detector. For the first time, morphology of the HAp particles was predicted by XRD, and it was verified by SEM. The results show that an equiaxed polycrystalline HAp particle with uniform porosity was produced at 900 °C. It indicates that a porous nanoHAp achieved by sintering at 900 °C can be an ideal candidate as an in situ scaffold for load-bearing tissue applications.

Noor Azuan Abu Osman

2012-12-01

105

Bone marrow changes after localized acute and fractionated x irradiation  

International Nuclear Information System (INIS)

These studies were performed to compare the effects of single and fractionated localized irradiation doses to bone marrow on depletion and recovery of various hemopoietic cell lines. Mice received radiation to right thighs while the rest of the body was shielded. Single exposures ranged from 1000 to 10,000 rad and fractionated exposures ranged from total doses of 1000 to 6000 rad. Animals were sacrificed from 1 to 84 days after exposures. Stained sections of femurs were studied for total cellularity, megakaryocytes, immature cells (pro- and basophilic erythroblasts, myeloblasts, and promyelocytes), and lymphoid cells (lymphocytes and monocytes). In general, a dose-time-dependent response depletion pattern was seen for various cellular elements examined irrespective of the mode of radiation exposure. With fractionated schedules, all hemopoietic cell lines with the exception of megakaryocytes attained essentially control values by 12 weeks after the last radiation exposure irrespective of the total radiation dose. Megakaryocytes appeared to be less efficient in regenerating in and/or repopulating the exposed marrow. With single exposures, all hemopoietic cell lines examined failed to regenerate at radiation doses above 5000 rad

106

Effect of microstructural changes on gasification reactivity of coal chars during low temperature gasification  

Energy Technology Data Exchange (ETDEWEB)

An attempt has been made to quantitatively investigate the effect of microstructural changes on gasification reactivity of coal chars. Pocahontas No. 3, Illinois No. 6, and Beulah-Zap coal char samples were gasified in 1% O{sub 2} at 500{sup o}C or 600{sup o}C up to 90% (daf) conversion, and their structure were observed under a high-resolution transmission electron microscope (HRTEM). A quantitative structural analysis was done based on HRTEM images to obtain structural parameters such as number of stacks, layer size diameter, and their distributions using an image analysis algorithm. Effect of mineral matter on structural changes was also studied by carrying out gasification experiments with demineralized chars. The gasification reactivity of these chars was correlated with the structural parameters. 29 refs., 9 figs., 3 tabs.

Sharma, A.; Kadooka, H.; Kyotani, T.; Tomita, A. [Tohoku University, Sendai (Japan). Inst. of Multidisciplinary Research for Advanced Materials

2002-02-01

107

Intraspinal dural-based primary osteoblastoma with aneurysmal bone cyst-like change.  

Science.gov (United States)

Osteoblastoma is a benign bone-forming neoplasm that occurs commonly in the posterior elements of the spine and the sacrum. However, so far there has been no report of intradural osteoblastoma described in the literature. We present a unique case of intraspinal dural-based osteoblastoma with aneurysmal bone cyst-like change without evidence of vertebral involvement. An 11-year-old Chinese girl presented with a 3-month history of gradually progressive back pain and a weakness of both lower limbs. Thoracic MRI revealed a well-demarcated subdural mass at the T5 level with heterogeneous enhancement. Histologically, the tumor was found to be attached to the dura and composed of numerous osteoid spicules and trabecular bone with diffusely scattered osteoclast-type, multinucleated giant cells. Ectactic blood vessels and blood-filled cystic spaces were also observed. A diagnosis of primary intraspinal dural-based osteoblastoma with aneurysmal bone cyst-like change was made. To our best knowledge, this is possibly the first case of primary osteoblastoma arising from meninges. Meningeal osteocartilaginous tumors are rare, with obscure histogenesis. The differential diagnosis of osteoblastoma in unusual locations is difficult and the confirmation of diagnosis should be cautiously made. Awareness of dural-based osteoblastoma and its histological features is important to avoid a diagnostic pitfall caused by histological similarities to other intra-craniospinal lesions with osteoid differentiation or bone formation. PMID:24984761

Fu, Xinge; Jiang, Juhong; Luo, Bo-Ning; Tian, Xiao-Ying; Li, Zhi

2014-10-01

108

Bone scintigraphy in diabetic osteoarthropathy  

International Nuclear Information System (INIS)

Bone scans of patients with diabetic osteoarthropathy of the ankle and foot were characterized by a combination of diffuse and focal increased uptake, similar to that seen with hyperemia and reactive new bone formation. Scintigraphy showed more extensive abnormalities than radiography, with the scan abnormalities sometimes preceding the radiographic changes. The clinical and scintigraphic appearance of osteoarthropathy may improve following strict diabetic control and non-weight-bearing

109

Analysis of X-ray manifestations and changes in dysplastic damages to the skull bones  

International Nuclear Information System (INIS)

The paper deals with the analysis of X-ray manifestations of osteodysplasia of skull bones in 136 patients of different ages. It presents the time course of changes in relation to the structural pattern of malformed osseous tissue, including those after radical and palliative surgical interventions

110

[Clinical and physiological evaluation of bone changes among astronauts after long-term space flights  

Science.gov (United States)

Results of the joint Russian/US studies of the effect of microgravity on bone tissues in 18 cosmonauts on return from 4.5- to 14.5-month long missions are presented. Dual-energy x-ray gamma-absorbtiometry (QDR-1000 W, Hologic, USA) was used to measure bone mineral density (BMD, g/cm2) and mineral content (BMC, g) in the whole body, the scalp including cervical vertebra, arms, ribs, sternal and lumbar regions of the spinal column, pelvis and legs. A clearly defined dependence of topography of changes upon the position of a skeletal segment in the gravity vector was established. The greatest BMD losses have been observed in the skeleton of the lower body, i.e. in pelvic bones (-11.99 +/- 1.22%), lumbar vertebra (-5.63 +/- 0.817%), and in proximal femur, particularly in the femoral neck (-8.17 +/- 1.24%). Bones of the upper skeleton were either unchanged (insignificant) or showed a positive trend. Overall changes in bone mass of the whole skeleton of male cosmonauts during the period of about 6 months on mission made up -1.41 +/- 0.406% and suggest the mean balance of calcium over flight equal to -227 +/- 62.8 mg/day. Reasoning is given to qualify these states of cosmonauts' bone tissues as local osteopenia. On the literature and results of authors' clinical evidence, discussed is availability of the densitometric data for predicting risk of trauma. A biological nature of the changes under observation is hypothesized.

Grigoriev, A. I.; Oganov, V. S.; Bakulin, A. V.; Poliakov, V. V.; Voronin, L. I.; Morgun, V. V.; Shnaider, V. S.; Murashko, L. V.; Novikov, V. E.; LeBlank, A.; Shakleford, L.; Schneider, V. S. (Principal Investigator); Leblanc, A. (Principal Investigator)

1998-01-01

111

Age-related molecular genetic changes of murine bone marrow mesenchymal stem cells  

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Full Text Available Abstract Background Mesenchymal stem cells (MSC are pluripotent cells, present in the bone marrow and other tissues that can differentiate into cells of all germ layers and may be involved in tissue maintenance and repair in adult organisms. Because of their plasticity and accessibility these cells are also prime candidates for regenerative medicine. The contribution of stem cell aging to organismal aging is under debate and one theory is that reparative processes deteriorate as a consequence of stem cell aging and/or decrease in number. Age has been linked with changes in osteogenic and adipogenic potential of MSCs. Results Here we report on changes in global gene expression of cultured MSCs isolated from the bone marrow of mice at ages 2, 8, and 26-months. Microarray analyses revealed significant changes in the expression of more than 8000 genes with stage-specific changes of multiple differentiation, cell cycle and growth factor genes. Key markers of adipogenesis including lipoprotein lipase, FABP4, and Itm2a displayed age-dependent declines. Expression of the master cell cycle regulators p53 and p21 and growth factors HGF and VEGF also declined significantly at 26 months. These changes were evident despite multiple cell divisions in vitro after bone marrow isolation. Conclusions The results suggest that MSCs are subject to molecular genetic changes during aging that are conserved during passage in culture. These changes may affect the physiological functions and the potential of autologous MSCs for stem cell therapy.

Webster Keith A

2010-04-01

112

Normal age-related changes in fluoride content of vertebral trabecular bone--relation to bone quality  

DEFF Research Database (Denmark)

In several clinical osteoporosis studies, fluoride treatment has been shown to have a positive effect on bone mass but without a concomitant decrease in vertebral fracture rate. In contrast, some studies have shown that increases in spinal BMD are also paralleled by decreased vertebral fracture incidence. We have previously demonstrated, in a pig model, that 6-month treatment with fluoride increased bone mass but decreased bone quality. The aim of the present study was to elucidate whether normal age-related fluoride accumulation in human bone per se influences bone quality. From 73 normal individuals, aged 20-91 years (36 females, 37 males) two trabecular bone cylinders were obtained from the central part of L3. Biomechanical competence, ash density, and fluoride content were assessed in one cylinder, and trabecular bone volume was determined in the other. The results showed an age-related decrease in bone mass for both men and women. Bone strength normalized for bone mass (bone quality also identical with bone material strength) also showed an age-related decrease in men and women. Bone fluoride concentration increased significantly in both sexes (range 463-4000 ppm). Multiple regression analyses disclosed that fluoride by itself had no influence on bone quality, in this study with a limited number of cases, when the influence of sex and age were taken into account. It is concluded that normal age-related accumulation of fluoride in vertebral trabecular bone does not seem to affect the quality of bone. Whether this is also the case during fluoride therapy has to be assessed.

Richards, A; Mosekilde, L

1994-01-01

113

Diet-induced (epigenetic) changes in bone marrow augment atherosclerosis.  

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Alterations in DNA methylation patterns in peripheral blood leukocytes precede atherosclerotic lesion development in mouse models of atherosclerosis and have been linked to cardiovascular death in patients. The aim of this study is to investigate the long-term changes induced by WTD feeding on BM cells and the consequences for atherosclerosis susceptibility. Hereto, WTD BM or Chow BM was transplanted into LDLR KO mice on chow. BM from WTD BM recipient mice exhibited hypomethylation of CpG regions in the genes encoding Pu.1 and IRF8, key regulators of monocyte proliferation and macrophage differentiation. In agreement, in blood, the numbers of leukocytes were 40% (P<0.05) higher as a result of an increase in F4/80(+) monocytes (3.4-fold; P<0.01). An increase of CD11c(++) cells was also found (2.4-fold; P<0.05). Furthermore, spleens were enlarged, and the percentage of F4/80(+) cells expressing CD86 was induced (1.8-fold; P<0.01), indicating increased activation of splenic macrophages. Importantly, mice reconstituted with WTD BM showed a significant, 1.4-fold (P<0.05) increase in aortic root plaque size in the absence of changes in serum cholesterol. We conclude that WTD challenge induces transplantable epigenetic changes in BM, alterations in the hematopoietic system, and increased susceptibility to atherosclerosis. Manipulation of the epigenome, when used in conjunction with blood lipid reduction, could thus prove beneficial to treat cardiovascular disorders. PMID:25024399

van Kampen, Erik; Jaminon, Armand; van Berkel, Theo J C; Van Eck, Miranda

2014-11-01

114

Adipokines and C-reactive protein in relation to bone mineralization in pediatric nonalcoholic fatty liver disease  

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Full Text Available AIM: To investigate bone mineral density (BMD in obese children with and without nonalcoholic fatty liver disease (NAFLD; and the association between BMD and serum adipokines, and high-sensitivity C-reactive protein (HSCRP. METHODS: A case-control study was performed. Cases were 44 obese children with NAFLD. The diagnosis of NAFLD was based on magnetic resonance imaging (MRI with high hepatic fat fraction (? 5%. Other causes of chronic liver disease were ruled out. Controls were selected from obese children with normal levels of aminotransferases, and without MRI evidence of fatty liver as well as of other causes of chronic liver diseases. Controls were matched (1- to 1-basis with the cases on age, gender, pubertal stage and as closely as possible on body mass index-SD score. All participants underwent clinical examination, laboratory tests, and whole body (WB and lumbar spine (LS BMD by dual energy X-ray absorptiometry. BMD Z-scores were calculated using race and gender specific LMS curves. RESULTS: Obese children with NAFLD had a significantly lower LS BMD Z-score than those without NAFLD [mean, 0.55 (95%CI: 0.23-0.86 vs 1.29 (95%CI: 0.95-1.63; P < 0.01]. WB BMD Z-score was also decreased in obese children with NAFLD compared to obese children with no NAFLD, though borderline significance was observed [1.55 (95%CI: 1.23-1.87 vs 1.95 (95%CI: 1.67-2.10; P = 0.06]. Children with NAFLD had significantly higher HSCRP, lower adiponectin, but similar leptin levels. Thirty five of the 44 children with MRI-diagnosed NAFLD underwent liver biopsy. Among the children with biopsy-proven NAFLD, 20 (57% had nonalcoholic steatohepatitis (NASH, while 15 (43% no NASH. Compared to children without NASH, those with NASH had a significantly lower LS BMD Z-score [mean, 0.27 (95%CI: -0.17-0.71 vs 0.75 (95%CI: 0.13-1.39; P < 0.05] as well as a significantly lower WB BMD Z-score [1.38 (95%CI: 0.89-1.17 vs 1.93 (95%CI: 1.32-2.36; P < 0.05]. In multiple regression analysis, NASH (standardized ? coefficient, -0.272; P < 0.01 and HSCRP (standardized ? coefficient, -0.192; P < 0.05 were significantly and independently associated with LS BMD Z-score. Similar results were obtained when NAFLD (instead of NASH was included in the model. WB BMD Z-scores were significantly and independently associated with NASH (standardized ? coefficient, -0.248; P < 0.05 and fat mass (standardized ? coefficient, -0.224; P < 0.05. CONCLUSION: This study reveals that NAFLD is associated with low BMD in obese children, and that systemic, low-grade inflammation may accelerate loss of bone mass in patients with NAFLD.

Lucia Pacifico

2013-01-01

115

Magnetic Resonance Imaging of the Clivus and Its Age-Related Changes in the Bone Marrow  

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Full Text Available Background: The clivus is a bone region between dorsum cella and foramen magnum. It can be evaluated very clearly in routine brain magnetic resonance imaging (MRI due to its central location.Objectives: Quantitative and qualitative evaluation of the clivus and its changes according to age in a group of healthy people.Patients and Methods: The transition of clival bone marrow to fatty marrow by the increase in age is examined by MRI in 105 men and 105 women who had no clival and bone marrow pathology on MRI. The clivus/pons, clivus/CSF intensity values and clival bone marrow imaging patterns according to age groups were prospectively evaluated using a 1.5 Tesla MR device.Results: When age groups were individually compared, there were meaningful statistical differences both in men and women in terms of clivus/CSF and clivus/pons intensity ratios (both Ps < 0.05. Clivus/pons and clivus/CSF intensity ratios were found to be increased with age in all cases. The distribution of age groups according to stages in all individuals was statistically meaningful (P < 0.05. When the appearance patterns of both genders in every ten-fold age were examined, stage III bone marrow was observed more in elder ages.Conclusions: As a result, besides the fact that standard ranges determined for clivus/CSF, clivus/pons intensity ratios according to age may be used in the assessment of potential pathological cases involving bone marrow; they can also be leading in the diagnosis of bone marrow diseases when taken into consideration together with clinical and laboratory data.

Ekrem Olcu

2011-12-01

116

Histopathological change of the metastatic bone marrow. Response for radio- and combination chemotherapy at autopsy cases  

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The purpose of this study was to determine the histopathologic therapeutic effects in metastatic bone marrow for various therapy in cancer patients. Autopsy cases at Shikoku Cancer Center Hospital, mainly cancer of breast, stomach, lung and prostate examined radiotherapy (28-60 Gy) and chemotherapy and/or endocrine chemotherapy (medroxyprogesterone acetate, tamoxifen). Histological evaluation of effects for radio-and chemotherapy have been criteria of UICC and criteria for the evaluation of the clinical and pathological effects by Japan Society for Cancer Therapy. The precise effects for various therapy is difficult to measure objectively in metastatic bone. Histopathologic changes of metastatic bone marrow for radiotherapy revealed decrease and degeneration of tumor cells - swelling, vacuoles of cytoplasm and nuclei, bizarre and giant multinucleated giant cells etc. Stromal reaction was found postnecrotic fresh and/or old granulation-fibrosis and hyalinization, woven bone formation and fatty marrow. Systemic therapy of breast cancer revealed stromal fibrosis and chondroid ossification more than other tumors and therapy. Morphological features of metastatic bone marrow at autopsy cases may be necessary from viewpoint of therapeutic effects. (author)

117

Histopathological change of the metastatic bone marrow. Response for radio- and combination chemotherapy at autopsy cases  

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The purpose of this study was to determine the histopathologic therapeutic effects in metastatic bone marrow for various therapy in cancer patients. Autopsy cases at Shikoku Cancer Center Hospital, mainly cancer of breast, stomach, lung and prostate examined radiotherapy (28-60 Gy) and chemotherapy and/or endocrine chemotherapy (medroxyprogesterone acetate, tamoxifen). Histological evaluation of effects for radio-and chemotherapy have been criteria of UICC and criteria for the evaluation of the clinical and pathological effects by Japan Society for Cancer Therapy. The precise effects for various therapy is difficult to measure objectively in metastatic bone. Histopathologic changes of metastatic bone marrow for radiotherapy revealed decrease and degeneration of tumor cells - swelling, vacuoles of cytoplasm and nuclei, bizarre and giant multinucleated giant cells etc. Stromal reaction was found postnecrotic fresh and/or old granulation-fibrosis and hyalinization, woven bone formation and fatty marrow. Systemic therapy of breast cancer revealed stromal fibrosis and chondroid ossification more than other tumors and therapy. Morphological features of metastatic bone marrow at autopsy cases may be necessary from viewpoint of therapeutic effects. (author)

Moriwaki, Shousuke; Mandai, Kouichi; Kataoka, Masaaki; Saeki, Hideyuki; Ohsumi, Syozo [Shikoku Cancer Center Hospital, Matsuyama (Japan)

2002-07-01

118

Changes in proximal femoral bone mineral density around a hydroxyapatite-coated hip joint arthroplasty.  

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Full Text Available OBJECTIVE: To present the results of a prospective analysis of proximal femoral bone mineral density changes around a hydroxyapatite-coated total hip joint replacement. METHODS: 14 patients with osteoarthritis of the hip were enrolled in the study and treated with an uncemented ABG prosthesis. Dual energy X-ray absorptiometry scanning was performed in 9 patients preoperatively, and at 3, 6, 12, and 24 months postoperatively. An orthopaedic software program was used to determine the bone mineral density in the proximal femur, expressed as a percentage of the preoperative value. RESULTS: The values of Gruen zones 1 to 6 averaged between 96.0% and 113.8% of the preoperative value by 24 months (overall average, 104.1%. In zone 7, however, there was a gradual decline in bone mineral density to an average of 72.1% of the preoperative value by 24 months. This represented ongoing loss of bone from the calcar; although this may not pose a problem to the prosthetic's short-term stability, it may render potential revision surgery more difficult. CONCLUSION: The initial outcome of uncemented total hip replacement appears to be promising. There was excellent maintenance of bone around the femoral component in all regions other than the calcar and lesser trochanter. Further scans are required to see if these trends continue in the long term.

Theis JC

2003-06-01

119

Assessing land-use change using the trace element chemistry of human bones (Invited)  

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Reconstruction of environmental life histories using the elemental chemistry of biominerals is becoming common in ecological research. Less common is the application of these approaches to reconstruct environmental records from human bones. Here we present trace element data from human long bone of various ages and environments. Specifically samples from poorhouse burials in Rochester, NY (1750’s) and Buffalo, NY (1855) and a pioneer burial site in Mt. Morris, NY (1810) and associated soil samples were analyzed by ICP-MS. Based on differences in soil type, geology, groundwater chemistry, diet, bone pathology, life style at time of death (diet etc.) we reconstructed environmental life histories of the three populations as well as identified differences between individuals attributable to life style. These data reveal the potential of human bone trace element chemistry to provide retrospective information regarding land-use. Using human bone chemistry of populations within a single area is it possible to assess long-term changes in land-use as reflective of diet, occupation, etc.

Hannigan, R. E.; Darrah, T. H.; Prutsman-Pfeiffer, J.

2009-12-01

120

Chronological changes in the microstructure of bone during peri-implant healing: a microcomputed tomographic evaluation.  

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Our objectives were to examine the titanium-bone interfaces chronologically and to clarify the process of osseointegration using microcomputed tomography (microCT). The mandibular premolars of 3 dogs were extracted and 12 weeks later 2 Straumann dental implants were installed in each quadrant. The microstructural changes at the bone-implant interface at the first, fourth, and eighth weeks after installation were evaluated by microCT and a 3-dimensional image was constructed. The microstructural measurements at the bone-implant interface, including the trabecular number (Tb.N), bone volume fraction (BV/TV), structure model index (SMI), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp) and connectivity density (Conn.D), were measured. Experimental outcomes were analysed for correlations between time and microstructural variables of trabecular bone. Tb.N increased significantly during the eighth week compared with that during the first and fourth week (p=0.001, 0.002). BV/TV increased generally with time and there were significant differences (p=0.003) between each time group. While Tb.Sp decreased with time and changed significantly during the eighth week compared with that during the first week (p=0.021), differences in SMI, Tb.Th and Conn.D did not differ significantly according to time of implant. The significant increase in the Tb.N and BV/TV during the eighth week after insertion of implants indicates that the formation of new bone before the eighth week is the key to osseointegration. PMID:25131999

Fang, Liang; Ding, Xi; Wang, Hui-Ming; Zhu, Xing-Hao

2014-11-01

 
 
 
 
121

Changes In Bone Sclerostin Levels In Mice After Ovariectomy Vary Independently Of Changes In Serum Sclerostin Levels  

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We examined the effects that ovariectomy had on sclerostin mRNA and protein levels in the bones of 8-week-old mice that were either sham-operated (SHAM) or ovariectomized (OVX) and then sacrificed 3 or 6 wks. later. In this model bone loss occurred between 3 and 5 wks. Post-surgery. In calvaria OVX significantly decrease sclerostin mRNA levels at 6 wks. post-surgery (by 52%) but had no significant effect at 3 wks. In contrast, sclerostin mRNA levels were significantly lower in OVX femurs at 3 wks. post-surgery (by 53%) but equal to that of SHAM at 6 wks. The effects of OVX on sclerostin were not a global response of osteocytes since they were not mimicked by changes in the mRNA levels for 2 other relatively osteocyte-specific genes: DMP-1 and FGF-23. Sclerostin protein decreased by 83% and 60%, respectively at 3 and 6 wks. post-surgery in calvaria and by 38% in lumbar vertebrae at 6 wks. We also detected decreases in sclerostin by immunohistochemistry in cortical osteocytes of the humerus at 3 wks. post-surgery. However, there were no significant effects of OVX on sclerostin protein in femurs or on serum sclerostin at 3 and 6 wks. post-surgery. These results demonstrate that OVX has variable effects on sclerostin mRNA and protein in mice, which are dependent on the bones examined and the time after surgery. Given the discrepancy between the effects of OVX on serum sclerostin levels and sclerostin mRNA and protein levels in various bones, these results argue that, at least in mice, serum sclerostin levels may not accurately reflect changes in the local production of sclerostin in bones. Additional studies are needed to evaluate whether this is also the case in humans. PMID:23044658

Jastrzebski, Sandra; Kalinowski, Judith; Stolina, Marina; Mirza, Faryal; Torreggiani, Elena; Kalajzic, Ivo; Won, Hee Yeon; Lee, Sun-Kyeong; Lorenzo, Joseph

2012-01-01

122

/ Calcium supplementation, bone mineral density and bone mineral content. Predictors of bone mass changes in adolescent mothers during the 6-month postpartum period  

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Full Text Available SciELO Venezuela | Language: English Abstract in spanish Suplementación con calcio, densidad mineral ósea y contenido mineral óseo. Predictores de cambios en la masa ósea en madres adolescentes a los 6 meses postparto. El objetivo del estudio fue determinar el efecto de dos formas de suplementare calcio sobre la densidad mineral ósea (DMO) y el contenido [...] mineral óseo (CMO), e identificar predictores de cambios en la masa ósea en madres adolescentes a los 6 meses postparto. Se realizó un estudio prospectivo, analítico y clínico en madres adolescentes (?19 años; n=37) de la ciudad de La Plata, Argentina. A partir de los 15 días postparto, las adolescentes fueron distribuidas al azar en 2 grupos y comenzaron con la suplementación con calcio; un grupo recibió productos lácteos (932 mg Ca; n=19) y el otro citrato de calcio (1000 mg calcio/día; n=18). Se midió peso, altura y consumo de alimentos y se determinó la DMO por DEXA a los 15 días (línea de base) y a los 6 meses postparto. También se determinó CMO, DMO corporal total y DMO de columna lumbar, cuello femoral, trocánter y cadera total. Se usaron modelos de regresión para identificar relaciones entre DMO corporal total y CMO con variables independientes (tipo de suplementación, meses de lactancia, peso a los 6 meses, porcentaje de cambio de peso, masa magra a los 6 meses, porcentaje de cambio de masa magra, consumo total de calcio). Los resultados muestran que los cambios en DMO y CMO en los distintos sitios fueron similares en ambos grupos, y que los cambios en los porcentajes de peso corporal e ingesta total de calcio fueron los principales factores predictivos. En conclusión, el efecto del calcio fue similar tanto con productos lácteos como con comprimidos. Los cambios porcentuales en peso corporal e ingesta total de calcio resultaron factores predictivos de los cambios de la DMO corporal total y el CMO. Abstract in english We determined the effect of calcium supplementation on bone mineral density (BMD) and bone mineral content (BMC) and identified predictors of bone mass changes in adolescent mothers 6 months postpartum. A prospective, analytical, clinical study was performed in adolescent mothers (?19 years old; n=3 [...] 7) from La Plata, Argentina. At 15 days postpartum, mothers were randomly assigned into one of two groups and started with calcium supplementation; one group received dairy products (932 mg Ca; n=19) and the other calcium citrate tablets (1000 mg calcium/day; n=18). Weight, height and dietary intake were measured and BMD was determined by DEXA at 15 days (baseline) and 6 months postpartum. BMC, total body BMD and BMD were assessed in lumbar spine, femoral neck, trochanter and total hip. Regression models were used to identify the relationship of total body BMD and BMC with independent variables (calcium supplementation, months of lactation, weight at 6 months, percent weight change, lean mass at 6 months, percent lean mass change, total calcium intake). Results showed that changes in BMD and BMC at the different sites were similar in both groups, and changes in percent body weight and total calcium intake were the main predictive factors. In conclusion, the effect of calcium was similar with either form of supplementation, i.e., dairy products or tablets, and changes in percent body weight and total calcium intake were predictors of total body BMD and BMC changes.

Agustina, Malpeli; María, Apezteguia; José L, Mansur; Alicia, Armanini; Melisa, acías Couret; Rosa, Villalobos; Marta, Kuzminczuk; Horacio F, Gonzalez.

123

Changes in graft thickness after skull defect reconstruction with autogenous split calvarial bone graft.  

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The ideal material for primary reconstruction of skull defect would be the autogenous bone. However, the long-term evaluation regarding the change in bone graft thickness has not been reported. In this article, we analyzed the thickness changes of the graft according to the time period. Between March 2005 and February 2011, a total of 29 patients underwent skull reconstruction with autogenous split calvarial bone grafts. After applying exclusion criteria, computed tomographic (CT) images of 15 patients were analyzed. The donor bone was harvested in full thickness as 1 piece and then as split. One half of the bone plate was transferred to the defect site; the other half, to the donor site. Both halves were fixed with titanium plates. To compare graft thickness changes, immediate postoperative and follow-up CT scans were analyzed by a single researcher. An anatomic reference was appointed for each patient, and the thickness of the graft on the same level was measured on time-series CT images. Collected data were analyzed with a polynomial random coefficient model. The main causes of the skull defects were trauma and tumor excision. In all cases, the graft thickness was not decreased but even increased in both the donor and recipient sites. The mean graft thicknesses between 6 months and 1 year after the surgery as well as those between 2 and 3 years after the surgery were 1.24-times and 1.56-times thicker than the immediate postoperative thickness, respectively. Graft thickness turned out to be either maintained or increased over time. PMID:25006904

Chang, Tack Jin; Choi, Jong Woo; Ra, Young Shin; Hong, Seok Ho; Cho, Young Hyun; Koh, Kyung Suk

2014-07-01

124

Paraphyseal changes on bone-age studies predict risk of delayed radiation-associated skeletal complications following total body irradiation  

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Children undergoing total body irradiation (TBI) often develop delayed skeletal complications. Bone-age studies in these children often reveal subtle paraphyseal changes including physeal widening, metaphyseal irregularity and paraphyseal exostoses. To investigate whether paraphyseal changes on a bone-age study following TBI indicate a predisposition toward developing other radiation-associated skeletal complications. We retrospectively reviewed medical records and bone-age studies of 77 children receiving TBI at our institution between 1995 and 2008 who had at least 2 years of clinical follow-up and one bone-age study after TBI. We graded bone-age studies according to the severity of paraphyseal changes. All documented skeletal complications following TBI were tabulated. Kendall's tau-b was used to examine associations between degree of paraphyseal change and development of a skeletal complication. Kendall's tau analyses showed that physeal widening and metaphyseal irregularity/sclerosis (tau = 0.87, P < 0.001) and paraphyseal exostoses (tau = 0.68, P < 0.001) seen on bone-age studies were significantly positively associated with the development of delayed skeletal complications following TBI. Thirty percent of children with no or mild paraphyseal changes developed a delayed skeletal complication, compared with 58% of children with moderate paraphyseal changes and 90% of children with severe paraphyseal changes. Paraphyseal changes identified on a bone-age study correlate positively with the development of delayed skeletal complications elsewhere in the skeleton following TBI. (orig.)

Kitazono Hammell, Mary T.; Edgar, J.C.; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Bunin, Nancy [The Children' s Hospital of Philadelphia, Oncology Division, BMT Section, Philadelphia, PA (United States)

2013-09-15

125

Age-related changes in resorption cavity characteristics in human trabecular bone.  

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The depth of resorption cavities in trabecular bone is an important determinant of bone structure and has implications relevant to the cellular pathophysiology of bone loss in osteoporosis. However, assessment of resorption depth has proved difficult and few data are available; in this study we report age-related changes in iliac crest trabecular bone obtained from 41 normal healthy subjects (21 female, 20 male) aged 22-80 years. Using 8-microns undecalcified sections stained with toluidine blue, resorption cavities were quantitatively assessed by a computerized technique in which the eroded bone surface is reconstructed and measurements made interactively. Maximum and mean cavity depth showed no significant correlation with age in either sex. The absolute length of eroded surface was unrelated to age but the eroded surface/BS (%) and the number of cavities/BS (/mm) showed a significant positive correlation with age (r = 0.384 and 0.386 respectively, p less than 0.05). No significant correlation was found between age and either cavity area or density. These results suggest that increased resorption depth does not contribute to age-related bone loss, although the possibility that deeper resorption cavities occur which result in trabecular penetration and are therefore unrecognizable cannot be discounted. The age-related increase in eroded surface/BS (%) reflects a decreased available trabecular surface and/or increased number of cavities rather than a greater surface length of individual cavities; alternatively it may indicate an increased resorption period. No evidence of increased resorption depth at the time of the menopause was found in this study. PMID:1790413

Croucher, P I; Garrahan, N J; Mellish, R W; Compston, J E

1991-09-01

126

Changes in calcitropic hormones, bone markers and insulin-like growth factor I (IGF-I) during pregnancy and postpartum : a controlled cohort study  

DEFF Research Database (Denmark)

Pregnancy and lactation cause major changes in calcium homeostasis and bone metabolism. This population-based cohort study presents the physiological changes in biochemical indices of calcium homeostasis and bone metabolism during pregnancy and lactation

MØller, U K; við Streym, Susanna

2013-01-01

127

Insight into changes during coagulation in NOM reactivity for trihalomethanes and haloacetic acids formation.  

Science.gov (United States)

Natural organic matter (NOM) in raw water can contribute in many ways to the poor quality of drinking water, including the formation of disinfection byproducts such as trihalomethanes (THM) and haloacetic acids (HAA) during disinfection. This paper investigates the role of individual NOM fractions on changes in THM and HAA formation during coagulation with iron chloride (FeCl3) and a combination of polyaluminium chloride and iron chloride (FeCl3/PACl). The dissolved organic carbon (DOC) in the raw water and after coagulation was fractionated into four fractions, based on their hydrophobicity. Fractionation showed that most of the DOC (68%) in the raw water comes from the fulvic acid fraction, yielding 41% of the total THM precursors and 21% of the total HAA precursors. Both coagulants remove the humic acid fraction, but result in different changes to the reactivity of the remaining NOM fractions towards THM and HAA formation, indicating that coagulation occurs by different pathways, depending upon the type of coagulant used. In particular, significant changes in the reactivities of the hydrophilic acidic and non-acidic fractions were observed. PMID:23428464

Tubi?, Aleksandra; Agbaba, Jasmina; Dalmacija, Božo; Molnar, Jelena; Maleti?, Snežana; Watson, Malcolm; Perovi?, Svetlana Ugar?ina

2013-03-30

128

Progression and association with lameness and racing performance of radiographic changes in the proximal sesamoid bones of young Standardbred trotters  

International Nuclear Information System (INIS)

Radiographic examination of the metacarpo- and metatarsophalangeal joints was performed on 753 Standardbred trotters (6-21 months of age): 21 showed obvious changes in 26 proximal sesamoid bones on lateromedial projection. The radiographic changes were divided into 6 different types: (1) irregular abaxial margin (8 horses); (2) enlargement of the sesamoid bone (6 horses); (3) 'fracture' or separate centre of ossification of the apex (4 horses); (4) vertical, non-articular fracture of the plantar part of the sesamoid bone (1 horse); (5) a small bony fragment located in a defect in the apical part of the bone (2 horses); and (6) multiple areas of decreased radiodensity (1 horse). Each horse displayed only one type of radiographic change except for one which possessed those of types 3 and 5. Follow-up radiographic examination of 21 of the 26 affected proximal sesamoid bones at approximately 6-month intervals revealed a reduction in the changes in 13 bones and an unaltered condition in 8. Lameness examination was performed on 16 of the 21 horses at 3 years of age and 14 (87.5%) were observed to be lame, but detected lameness did not seem to be referrable to the sesamoid changes. Earnings after the racing season as 3- and 4-year-old horses showed no differences (P > 0.05) between horses with radiographic changes in the proximal sesamoid bones and those without such changes

129

Changes in markers of bone formation and resorption in a bed rest model of weightlessness  

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To study the mechanism of bone loss in physical unloading, we examined indices of bone formation and bone resorption in the serum and urine of eight healthy men during a 7 day -6 degrees head-down tilt bed rest. Prompt increases in markers of resorption--pyridinoline (PD), deoxypyridinoline (DPD), and hydroxyproline (Hyp)/g creatinine--during the first few days of inactivity were paralleled by tartrate-resistant acid phosphatase (TRAP) with significant increases in all these markers by day 4 of bed rest. An index of formation, skeletal alkaline phosphatase (SALP), did not change during bed rest and showed a moderate 15% increase 1 week after reambulation. In contrast to SALP, serum osteocalcin (OC) began increasing the day preceding the increase in Hyp, remained elevated for the duration of the bed rest, and returned to pre-bed rest values within 5 days of reambulation. Similarly, DPD increased significantly at the onset of bed rest, remained elevated for the duration of bed rest, and returned to pre-bed rest levels upon reambulation. On the other hand, the other three indices of resorption, Hyp, PD, and TRAP, remained elevated for 2 weeks after reambulation. The most sensitive indices of the levels of physical activity proved to be the noncollagenous protein, OC, and the collagen crosslinker, DPD. The bed rest values of both these markers were significantly elevated compared to both the pre-bed rest values and the post-bed rest values. The sequence of changes in the circulating markers of bone metabolism indicated that increases in serum OC are the earliest responses of bone to head-down tilt bed rest.

Lueken, S. A.; Arnaud, S. B.; Taylor, A. K.; Baylink, D. J.

1993-01-01

130

Roentgenogrammetry in diagnosis of age-dependent changes of the bone tissue  

International Nuclear Information System (INIS)

Roentgenogrammetry was used to analyze 120 x-ray films of the right clavicle obtained at autopsy of female and male corpses aged 20-80. It was determined that the indices of the x-ray film correlated with the age-dependent changes in the bone tissue which occurred due to involution osteoporosis and could be of practical value for personality identification in forensics medical expertise

131

Determining Normal Range of Vitamin D Based on PTH and Bone Mineral Density Changes  

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Full Text Available PTH is the most important factor which control calcium homeostasis in the body in this study we tried to determine the normal range of PTH and Vitamin D with examining the relation between PTH and bone density and Vitamin D on the base of bones biological changes. Our subjects were, 20 to 69 years-old men and women of Tehran. Serum volume of PTH and vitamin D in different decades of life had significant difference. Range of serum PTH in osteporotic persons was 29.7-38 pgr/lit (95% SD. This range for non osteporotic persons was 24.33-30.2 pgr/lit. In this study ranges below 18 nmol/lit was considered as severe vitamin D deficiency and 23-36nmol/lit as mild deficiency. So the volume more than 36 nmol/lit volumes was normal range of vitamin D. it seems that biological changes of bones associate more with ranges of vitamin D which causes significant changes in PTH.

B Larijani

2004-11-01

132

The exploration of the changes in bone metabolism in patients with abnormal thyroid function  

International Nuclear Information System (INIS)

To explore the changes in bone metabolism with abnormal thyroid function, BGP and PTH in 91 patients with hyperthyroidism, 37 patients with hypothyroidism, 51 controls, were measured by means of IRMA, calcaneus heel bone density (BMD) was measured by means of 241Am single photon absorptiometry. BGP levels in hyperthyroidism were significantly higher than those in controls (P < 0.001). BGP levels in hypothyroidism were significantly lower than those in controls (P < 0.001). PTH levels in hyperthyroidism were a little lower than those in controls (P < 0.05). PTH levels in hypothyroidism were significantly higher than those in controls (P < 0.001). The measurement of BMD showed that the prevalence rates of osteoporosis (OP) in hyperthyroidism and hypothyroidism were significantly higher than those in controls. In hyperthyroidism and hypothyroidism groups the age of OP tends to be younger. The patients with hyperthyroidism over 55 years of age were all suffered from OP. The changes in BGP and PTH were earlier than BMD, so BGP and PTH can be used as sensitive indicator of the changes in bone metabolism with abnormal thyroid function, especially for curative effect observations

133

A conformational change of C-reactive protein in burn wounds unmasks its proinflammatory properties.  

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Tissue damage in burn injury leads to a rapid increase of leukocytes and acute phase reactants. Plasma levels of C-reactive protein (CRP) rise within hours after the insult. No deficiency of this protein has been reported in humans, suggesting it plays a pivotal role in innate immunity. CRP in circulation is composed of five identical subunits [pentameric CRP (pCRP)]. Recently, deposits of structurally modified CRP (mCRP) have been found in inflammatory diseases. Little is known about this structural change and how it affects CRP functions. We analyzed CRP deposits in burn wounds and serum by immunohistochemistry, western blot and dot blot analysis. CRP was deposited in necrotic and inflamed tissue, but not in adjacent healthy tissue. Tissue deposited CRP was detected by mCRP-specific antibodies and structurally different from serum pCRP. mCRP but not pCRP induced reactive oxygen species production by monocytes and facilitated uptake of necrotic Jurkat cells by macrophages. In addition, it accelerated migration of keratinocytes in a scratch wound assay. The structural changes that occur in pCRP upon localization to damaged and inflamed tissue in burn wounds result in a functionally altered protein with distinct functions. mCRP exhibits opsonic, proinflammatory and promigratory properties which modulate wound healing. PMID:24844702

Braig, David; Kaiser, Benedict; Thiele, Jan R; Bannasch, Holger; Peter, Karlheinz; Stark, G Björn; Koch, Hans-Georg; Eisenhardt, Steffen U

2014-08-01

134

Findings of skin and bones in mastocytosis  

International Nuclear Information System (INIS)

The syndrome of mastocytosis can include isolated urticaria pigmentosa, systemic mastocytosis, or the extremely rare form of mast cell leucemia. Our investigations of many patients have shown more frequently than earlier suspected, that the mastocytosis is a systemic disease. The frequency of attacked bone marrow is noteworthy. Because of the inflammatorygranulomatous manifestation in bone marrow, considerations of the pathogenesis of an immune and reactive event are taken into account. The mast cell granulomas are mostly found in the endosteal region, which is the reason for frequenctly occurring bone lesions (half on all patients show bone lesions). The bone changes can develop generalized (osteoporosis-osteosclerosis) or localized (osteolytic-osteosclerotic foci). In clinical work bone biopsies and skeletal radiology are supplementing each other: bone biopsy and skin biopsy give the first diagnosis of mastocytosis and reveal the systemic disease; X-ray pictures give information of shape and dimension of the induced osteopathy. (orig.)

135

Findings of skin and bones in mastocytosis  

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The syndrome of mastocytosis can include isolated urticaria pigmentosa, systemic mastocytosis, or the extremely rare form of mast cell leucemia. Our investigations of many patients have shown more frequently than earlier suspected, that the mastocytosis is a systemic disease. The frequency of attacked bone marrow is noteworthy. Because of the inflammatory granulomatous manifestation in bone marrow, considerations of the pathogenesis of an immune and reactive event are taken into account. The mast cell granulomas are mostly found in the endosteal region, which is the reason for frequently occurring bone lesions (half of all patients show bone lesions). The bone changes can develop generalized (osteoporosis-osteosclerosis) or localized (osteolytic-osteosclerotic foci). In clinical work bone biopsies and skeletal radiology are supplementing each other: bone biopsy and skin biopsy give the first diagnosis of mastocytosis and reveal the systemic disease; X-ray pictures give information of shape and dimension of the induced osteopathy.

Rohner, H.G.; Bartl, R.; Koischwitz, D.; Rodermund, O.E.

1982-12-01

136

[Severe microcytic anemia with megaloblastic changes in the bone marrow. A hematological paradoxon?].  

Science.gov (United States)

We discuss the case of a 32 year-old male with severe microcytic anemia (hemoglobin 2,9 g/dl) and megaloblastic changes in the bone marrow. The patient reported of substantial dietary weight loss. The family history was positive for beta-thalassemia. Previous blood work showed iron deficiency with mild anemia. Further work-up verified beta-thalassemia minor and revealed severely decreased vitamin B12 levels with positive anti intrinsic-factor antibodies, pathognomonic for autoimmune pernicious anemia. The paradoxon therefore dissolved as a pernicious anemia with megaloblastic changes with microcytic erythrocytes due to beta-thalassemia. PMID:19536514

Reibke, R; Hausmann, A; Cnossen, J; Hiddemann, W; Spiekermann, K; Braess, J

2009-07-01

137

The radiographic study of cortical changes of bone caused by jaw lesions  

International Nuclear Information System (INIS)

To investigate the diagnostic significance of cortical changes in the bone of diseased jaws utilizing computed tomography (CT). Computed tomographic images of 91 patients, consisting of 7 osteomyelitis, 46 cysts, 18 benign tumors, and 20 malignant tumors, were analyzed. The pattern of cortical expansion was classified into three types: no expansion (N), buccal or lingual expansion (B/L), and buccolingual expansion (B and L). The pattern of cortical destruction was classified into four types: no destruction (N), point destruction (PO), gross destruction (GR), and permeative destruction (PE). The pattern of periosteal reaction was classified into four types: parallel, irregular, spicule, and Codmans triangle. The relationship between the pattern of cortical bone changes and diseases of the jaws was assessed. When the pattern of cortical expansion was compared to diseases of the jaw, N-type was most prevalent in cases of osteomyelitis and malignant tumors, B/L-type with cysts, and BandL-types with benign tumors. Comparison between the pattern of cortical bone destruction with diseases of the jaw showed strong correlations between PO and PE-types to osteomyelitis, N-type with cysts, N and GR-types with benign tumors, and GR-type with malignant tumors. Finally, the relationship between the pattern of periosteal reaction to diseases of the jaw showed a strong correlation between parallel-type to osteomyelitis and spicule-type to malignant tumors. The pattern of cortical expansion and cortical destruction is useful in differentiating diseases of the jaws.

138

MEASUREMENT OF TEMPERATURE DEPENDENT CHANGES IN BONE MARROW USING A RAPID CHEMICAL SHIFT IMAGING TECHNIQUE  

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PURPOSE To provide quantitative temperature monitoring for thermal therapies in bone marrow by measuring temperature-dependent signal changes in the bone marrow of ex vivo canine femurs heated with a 980-nm laser at 1.5T and 3.0T. MATERIALS AND METHODS Using a multi-gradient echo (? 16) acquisition and signal modeling with the Stieglitz-McBride algorithm, the temperature sensitivity coefficients (TSC, ppm/°C) of water and multiple lipid components’ proton resonance frequency (PRF) values are measured at high spatiotemporal resolutions (1.6 × 1.6 × 4mm3, ? 5sec). Responses in R2* and amplitudes of each peak were also measured as a function of temperature simultaneously. RESULTS Calibrations demonstrate that lipid signal may be used to compensate for B0 errors to provide accurate temperature readings (<1.0°C). Over a temperature range of 17.2 to 57.2 °C, the TSC’s after correction to a bulk methylene reference are ?0.87 × 10?2±4.7 × 10?4 ppm/°C and ?0.87 × 10?2±4.0x10?4 ppm/°C for 1.5T and 3.0T, respectively. CONCLUSION Overall, we demonstrate that accurate and precise temperature measurements can be made in bone marrow. In addition, the relationship of R2* and signal amplitudes with respect to temperature are shown to differ significantly where conformal changes are predicted by Arrhenius rate model analysis. PMID:21509871

Taylor, Brian A.; Elliott, Andrew M.; Hwang, Ken-Pin; Shetty, Anil; Hazle, John D.; Stafford, R. Jason

2011-01-01

139

Microglia change from a reactive to an age-like phenotype with the time in culture  

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Full Text Available Age-related neurodegenerative diseases have been associated with chronic neuroinflammation and microglia activation. However, cumulative evidence supports that inflammation only occurs at an early stage once microglia change the endogenous characteristics with ageing and switch to irresponsive/senescent and dystrophic phenotypes with disease progression. Thus, it will be important to have the means to assess the role of reactive and aged microglia when studying advanced brain neurodegeneration processes and age-associated related disorders. Yet, most studies are done with microglia from neonates since there are no adequate means to isolate degenerating microglia for experimentation. Indeed, only a few studies report microglia isolation from aged animals, using either short-term cultures or high concentrations of mitogens in the medium, which trigger microglia reactivity. The purpose of this study was to develop an experimental process to naturally age microglia after isolation from neonatal mice and to characterize the cultured cells at 2 days in vitro (DIV, 10 DIV and 16 DIV. We found that 2 DIV (young microglia had predominant amoeboid morphology and markers of stressed/reactive phenotype. In contrast, 16 DIV (aged microglia evidenced ramified morphology and increased metalloproteinase (MMP-2 activation, as well as reduced MMP-9, glutamate release and nuclear factor kappa-B activation, in parallel with decreased expression of Toll-like receptor (TLR-2 and TLR-4, capacity to migrate and phagocytose. These findings together with the reduced expression of microRNA (miR-124, and miR-155, decreased autophagy, enhanced senescence associated beta-galactosidase activity and elevated miR-146a expression, are suggestive that 16 DIV cells mainly correspond to irresponsive/senescent microglia. Data indicate that the model represent an opportunity to understand and control microglial aging, as well as to explore strategies to recover microglia surveillance function.

Adelaide Fernandes

2014-06-01

140

Microglia change from a reactive to an age-like phenotype with the time in culture.  

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Age-related neurodegenerative diseases have been associated with chronic neuroinflammation and microglia activation. However, cumulative evidence supports that inflammation only occurs at an early stage once microglia change the endogenous characteristics with aging and switch to irresponsive/senescent and dystrophic phenotypes with disease progression. Thus, it will be important to have the means to assess the role of reactive and aged microglia when studying advanced brain neurodegeneration processes and age-associated related disorders. Yet, most studies are done with microglia from neonates since there are no adequate means to isolate degenerating microglia for experimentation. Indeed, only a few studies report microglia isolation from aged animals, using either short-term cultures or high concentrations of mitogens in the medium, which trigger microglia reactivity. The purpose of this study was to develop an experimental process to naturally age microglia after isolation from neonatal mice and to characterize the cultured cells at 2 days in vitro (DIV), 10 DIV, and 16 DIV. We found that 2 DIV (young) microglia had predominant amoeboid morphology and markers of stressed/reactive phenotype. In contrast, 16 DIV (aged) microglia evidenced ramified morphology and increased matrix metalloproteinase (MMP)-2 activation, as well as reduced MMP-9, glutamate release and nuclear factor kappa-B activation, in parallel with decreased expression of Toll-like receptor (TLR)-2 and TLR-4, capacity to migrate and phagocytose. These findings together with the reduced expression of microRNA (miR)-124, and miR-155, decreased autophagy, enhanced senescence associated beta-galactosidase activity and elevated miR-146a expression, are suggestive that 16 DIV cells mainly correspond to irresponsive/senescent microglia. Data indicate that the model represent an opportunity to understand and control microglial aging, as well as to explore strategies to recover microglia surveillance function. PMID:24917789

Caldeira, Cláudia; Oliveira, Ana F; Cunha, Carolina; Vaz, Ana R; Falcão, Ana S; Fernandes, Adelaide; Brites, Dora

2014-01-01

 
 
 
 
141

Bone metabolism in obesity: changes related to severe overweight and dietary weight reduction.  

DEFF Research Database (Denmark)

A non-invasive evaluation of bone metabolism was performed in 44 morbidly obese patients before and after a mean weight loss of 22.4 kg (range 7.9-43.4 kg) after 2 months and a further weight loss of 7.3 kg after 8 months (0.8-20.0 kg). This weight reduction was obtained by a nutritionally adequate very-low-calorie diet. Before treatment the bone mineral content of the distal forearm was increased compared to normals (51.9 U vs. 43.7 U, p < 0.001). Bone formation was evaluated by serum alkaline phosphatase and serum osteocalcin. Serum alkaline phosphatase was increased (187.8 U/l vs 147.4 U/l, p < 0.001) while serum osteocalcin was lower than in the controls (0.67 nmol/l vs 0.98 nmol/l, p < 0.01). Bone resorption, as measured by the urinary hydroxyproline/creatinine ratio, was not increased in the obese patients (19.2 molar ratio x 10(-3) vs 16.7 molar ratio x 10(-3), NS). After 2 months, the bone mineral content had declined by 3.3%. Serum alkaline phosphatase remained unchanged (187.8 U/l vs 186.9 U/l, NS) but serum osteocalcin demonstrated a significant rise (3.94 nmol/l vs 10.53 nmol/l, p < 0.001), parallel to changes in the hydroxyproline/creatinine ratio (19.2 molar ratio x 10(-3) vs 25.2 molar ratio x 10(-3), p < 0.001). At 8 months, no further change in the bone mineral content was seen. The hydroxyproline/creatinine ratio did still increase (from 25.8 molar ratio x 10(-3) to 30.1 molar ratio x 10(-3), p < 0.05), while serum alkaline phosphatase and serum osteocalcin remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyldstrup, Lars; Andersen, T

1993-01-01

142

Bone Mineral Change During Experimental Calcination: An X-ray Diffraction Study.  

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The effects of calcination (400-1200°C) on pig bones have been studied using powder X-ray diffraction (XRD) and secondary modifications, such as color change and weight loss. The characterisation by powder XRD confirmed the presence of the crystalline phase of hydroxyapatite, and comparison of the results obtained at different temperatures suggested that at 650°C, all the organic components and carbonate substitutions were completely removed. Accordingly, these samples were white. In addition, the crystallinity degree and the crystallite size progressively increased with the calcination temperature until 650°C, remaining stable until 1200°C. Below 650°C, bone samples presented organic compounds, resulting in background noise in the diffractogram and gray or black color. In addition, impurities in the lattice correspond to low crystallite sizes. PMID:24962811

Galeano, Sergio; García-Lorenzo, Mari Luz

2014-11-01

143

A study on the spectral changes of reactive textile dyes and their implications for online control of dyeing processes  

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Evidence is presented that confirms the colour changes of a widely used trichromatic mixture of bifunctional reactive dyes (Levafix CA) under alkaline conditions, showing that they occur slowly and throughout the dyeing time, and not instantly after alkali addition to the dyebath. Thus, it is impossible to determine the specific absorptivity of the dyes at each moment of the dyeing process. An investigation into the relationship of the type of reactive group to the dye and the visible spectra...

Santos, Jorge Gomes; Soares, Grac?a M. B.; Hrdina, Radim; Campos, Ana M. F. Oliveira; Gomes, Jaime Rocha

2009-01-01

144

On RELAP5-simulated High Flux Isotope Reactor reactivity transients: Code change and application  

International Nuclear Information System (INIS)

This paper presents a new and innovative application for the RELAP5 code (hereafter referred to as ''the code''). The code has been used to simulate several transients associated with the (presently) draft version of the High-Flux Isotope Reactor (HFIR) updated safety analysis report (SAR). This paper investigates those thermal-hydraulic transients induced by nuclear reactivity changes. A major goal of the work was to use an existing RELAP5 HFIR model for consistency with other thermal-hydraulic transient analyses of the SAR. To achieve this goal, it was necessary to incorporate a new self-contained point kinetics solver into the code because of a deficiency in the point-kinetics reactivity model of the Mod 2.5 version of the code. The model was benchmarked against previously analyzed (known) transients. Given this new code, four event categories defined by the HFIR probabilistic risk assessment (PRA) were analyzed: (in ascending order of severity) a cold-loop pump start; run-away shim-regulating control cylinder and safety plate withdrawal; control cylinder ejection; and generation of an optimum void in the target region. All transients are discussed. Results of the bounding incredible event transient, the target region optimum void, are shown. Future plans for RELAP5 HFIR applications and recommendations for code improvements are also discussed

145

High-signal T2 changes of the bone marrow of the foot and ankle in children: red marrow or traumatic changes?  

International Nuclear Information System (INIS)

High-signal T2-weighted bone marrow changes can be found in both bone marrow edema and hematopoietic marrow and are often seen on pediatric MR images of the feet and ankle. To evaluate whether high-signal T2 changes of the bone marrow seen on pediatric MRI of feet and ankles represent residual hematopoietic marrow. A total of 402 bones in 41 pediatric MRI studies of feet and ankles (34 children, 1-18 years) were reviewed by two observers who were blinded to the patients' ages. The studies were reviewed for the presence of high-signal changes of the bone marrow on sagittal fluid-sensitive images. The frequency and location of these foci were correlated with the patients' ages. High-signal T2 changes of the bone marrow were seen in 45/402 bones (11%) and in 24/41 patients younger than 16 years (59%). The changes were most commonly located in the calcaneus (54%), followed by the talus (35%) and navicular bone (35%), invariably at the endosteal surface. In 16 ankles, such foci were seen in the feet but not in the distal tibia/fibula. Symmetric presence (two ankles) or absence (four ankles) of high-signal marrow were seen in six of seven patients with bilateral ankles. High-signal T2 changes of the bone marrow in pediatric feet and ankle MRIs have a symmetric, fairly consistent pattern and disappear after the age of 15 years. We believe that these high-signal areas are normal and represent residual hematopoietic marrow. (orig.)

146

High-signal T2 changes of the bone marrow of the foot and ankle in children: red marrow or traumatic changes?  

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High-signal T2-weighted bone marrow changes can be found in both bone marrow edema and hematopoietic marrow and are often seen on pediatric MR images of the feet and ankle. To evaluate whether high-signal T2 changes of the bone marrow seen on pediatric MRI of feet and ankles represent residual hematopoietic marrow. A total of 402 bones in 41 pediatric MRI studies of feet and ankles (34 children, 1-18 years) were reviewed by two observers who were blinded to the patients' ages. The studies were reviewed for the presence of high-signal changes of the bone marrow on sagittal fluid-sensitive images. The frequency and location of these foci were correlated with the patients' ages. High-signal T2 changes of the bone marrow were seen in 45/402 bones (11%) and in 24/41 patients younger than 16 years (59%). The changes were most commonly located in the calcaneus (54%), followed by the talus (35%) and navicular bone (35%), invariably at the endosteal surface. In 16 ankles, such foci were seen in the feet but not in the distal tibia/fibula. Symmetric presence (two ankles) or absence (four ankles) of high-signal marrow were seen in six of seven patients with bilateral ankles. High-signal T2 changes of the bone marrow in pediatric feet and ankle MRIs have a symmetric, fairly consistent pattern and disappear after the age of 15 years. We believe that these high-signal areas are normal and represent residual hematopoietic marrow. (orig.)

Shabshin, Nogah [Thomas Jefferson Medical College, Department of Radiology, Philadelphia, PA (United States); Chaim Sheba Medical Center, Department of Diagnostic Imaging, Tel-HaShomer (Israel); Schweitzer, Mark E. [NYU/Hospital for Joint Diseases, Department of Radiology, New York, NY (United States); Morrison, William B. [Thomas Jefferson Medical College, Department of Radiology, Philadelphia, PA (United States); Carrino, John A. [Thomas Jefferson Medical College, Department of Radiology, Philadelphia, PA (United States); Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Keller, Marc S.; Grissom, Leslie E. [DuPont Hospital for Children, Department of Medical Imaging, Wilmington, DE (United States)

2006-07-15

147

Bone Density Changes After Radiation for Extremity Sarcomas: Exploring the Etiology of Pathologic Fractures  

International Nuclear Information System (INIS)

athologic fracture in irradiated bones is likely multifactorial, including possible alterations in bone remodeling that can result in stable, or even increased, bone density. Further clinical and basic studies are needed to confirm our unexpected findings.

148

Dietary Intake Can Predict and Protect Against Changes in Bone Metabolism during Spaceflight and Recovery (Pro K)  

Science.gov (United States)

Bone loss is not only a well-documented effect of spaceflight on astronauts, but also a condition that affects millions of men and women on Earth each year. Many countermeasures aimed at preventing bone loss during spaceflight have been proposed, and many have been evaluated to some degree. To date, those showing potential have focused on either exercise or pharmacological interventions, but none have targeted dietary intake alone as a factor to predict or minimize bone loss during spaceflight. The "Dietary Intake Can Predict and Protect against Changes in Bone Metabolism during Spaceflight and Recovery" investigation ("Pro K") is one of the first inflight evaluations of a dietary countermeasure to lessen bone loss of astronauts. This protocol will test the hypothesis that the ratio of acid precursors to base precursors (specifically animal protein to potassium) in the diet can predict directional changes in bone mineral during spaceflight and recovery. The ratio of animal protein to potassium in the diet will be controlled for multiple short (4-day) periods before and during flight. Based on multiple sets of bed rest data, we hypothesize that a higher ratio of the intake of animal protein to the intake of potassium will yield higher concentrations of markers of bone resorption and urinary calcium excretion during flight and during recovery from bone mineral loss after long-duration spaceflight.

Smith, Scott M.; Zwart, S. R.; Shackelford, L.; Heer, M.

2009-01-01

149

Developmental changes of proteins and concanavalin A reactive glycoproteins in growth cones from rat forebrain.  

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Growth cones were isolated from the forebrains of 1, 5 and 9 days-old rats. The ultrastructural characterization of the obtained subcellular fractions reveals that two of them (GC1 and GC2) contain predominantly growth cones. It was found that the protein content of the membranes contained in these fractions increases 7.5 times, while in whole forebrain the increase is only 3 times, showing that during the studied developmental period there is a predominant protein enrichment of the specialized brain structures (e.g. growth cones). Electrophoretic studies show that there are characteristic changes of the Coomassie Brilliant Blue R250 staining and concanavalin A reactive protein profiles. Comparison of the protein patterns of growth cones to those of synaptosomes from mature forebrain reveal a number of bands, which appear to be characteristic for one of these structures. The possible roles of the developmentally controlled proteins in the processes of synaptogenesis is discussed. PMID:1571950

Venkov, L; Kirazov, L; Vassileva, E; Kirazov, E

1992-04-01

150

Methods for modeling impact-induced reactivity changes in small reactors.  

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This paper describes techniques for determining impact deformation and the subsequent reactivity change for a space reactor impacting the ground following a potential launch accident or for large fuel bundles in a shipping container following an accident. This technique could be used to determine the margin of subcriticality for such potential accidents. Specifically, the approach couples a finite element continuum mechanics model (Pronto3D or Presto) with a neutronics code (MCNP). DAGMC, developed at the University of Wisconsin-Madison, is used to enable MCNP geometric queries to be performed using Pronto3D output. This paper summarizes what has been done historically for reactor launch analysis, describes the impact criticality analysis methodology, and presents preliminary results using representative reactor designs.

Tallman, Tyler N.; Radel, Tracy E.; Smith, Jeffrey A.; Villa, Daniel L.; Smith, Brandon M. (U. of Wisconsin, Madison, WI); Radel, Ross F.; Lipinski, Ronald J.; Wilson, Paul Philip Hood (U. of Wisconsin, Madison, WI)

2010-10-01

151

Ion implantation induced structural changes in reactively sputtered Cr-N layers on Si substrates  

International Nuclear Information System (INIS)

This paper presents a study of the structure and composition of reactively sputtered Cr-N layers as a function of deposition parameters, and the effects of ion implantation on these structures. The layers were deposited on (1 0 0) Si substrates to a thickness of 240-280 nm, at different nitrogen partial pressure, and subsequently irradiated with 120 keV Ar ions. Structural characterisation of the samples was performed with Rutherford backscattering spectroscopy, transmission electron microscopy and X-ray diffraction analysis. We also measured their electrical resistivity with a four point probe. It was found that the layers grow in form of columnar structures, and their composition, Cr2N or CrN, strongly depends on the nitrogen partial pressure during deposition. Ion irradiation induces local micro-structural changes, formation of nano-particles and defects, which can be nicely correlated to the measured electrical resistivity

152

Changes in Cytokines of the Bone Microenvironment during Breast Cancer Metastasis  

International Nuclear Information System (INIS)

It is commonly accepted that cancer cells interact with host cells to create a microenvironment favoring malignant colonization. The complex bone microenvironment produces an ever changing array of cytokines and growth factors. In this study, we examined levels of MCP-1, IL-6, KC, MIP-2, VEGF, MIG, and eotaxin in femurs of athymic nude mice inoculated via intracardiac injection with MDA-MB-231GFP human metastatic breast cancer cells, MDA-MB-231 BRMS1GFP, a metastasis suppressed variant, or PBS. Animals were euthanized (day 3, 11, 19, 27 after injection) to examine femoral cytokine levels at various stages of cancer cell colonization. The epiphysis contained significantly more cytokines than the diaphysis except for MIG which was similar throughout the bone. Variation among femurs was evident within all groups. By day 27, MCP-1, MIG, VEGF and eotaxin levels were significantly greater in femurs of cancer cell-inoculated mice. These pro-osteoclastic and angiogenic cytokines may manipulate the bone microenvironment to enhance cancer cell colonization

153

Changes in the serum sex steroids, IL-7 and RANKL-OPG system after bone marrow transplantation: influences on bone and mineral metabolism.  

Science.gov (United States)

This study prospectively investigated the changes of the serum levels of the sex steroids, IL-7, soluble receptor activator of nuclear factor kappaB ligand (sRANKL) and osteoprotegerin (OPG) in bone marrow transplantation (BMT) recipients. This study also examined whether the changes of these cytokine levels and sex steroids actually influence bone turnover and post-BMT bone loss by correlation analysis. Data were analyzed from 39 patients (33.6+/-6.4 years, 19 men and 20 women) who had DXA performed before BMT and at 1 year after BMT. The bone turnover markers, sex steroids and the cytokine levels were measured before BMT and serially after BMT. The mean bone loss in the lumbar spine and the total proximal femur was 5.9% (P estradiol levels declined at 1 week after BMT, and they did not recover to the basal levels. For the male recipients, the testosterone levels decreased at 1 week and then it increased to its baseline level. The IL-7 levels reached their maximum at 1 week and then declined to baseline level by 3 months. The serum sRANKL, OPG levels and the sRANKL/OPG ratio showed their peak at post-BMT 3 weeks. The mean daily dose of steroid was associated with suppressed bone formation, enhanced bone resorption and increased sRANKL levels. The IL-7 levels were also noted to be either positively correlated with the levels of ICTP or they were negatively correlated with the levels of osteocalcin at 1 and 3 weeks after BMT. Bone loss at the lumbar spine and the proximal femur was influenced by the decreased sex steroids and increased IL-7 levels. During the observation period, the IL-7 levels showed positive correlations with the sRANKL levels and the sRANKL/OPG ratio. For the female patients, the serum IL-7 levels were negatively associated with the estradiol levels at 1 and 3 weeks after BMT. All these findings suggest that IL-7 plays an important role for post-BMT bone loss, and this possibly happens via the RANKL pathway. These data also suggest that the up-regulation of IL-7 during the early post-BMT period may result from a deficiency of estrogen. PMID:16905375

Baek, Ki Hyun; Oh, Ki Won; Lee, Won Young; Tae, Hyun Jung; Rhee, Eun Jung; Han, Je Ho; Cha, Bong Yun; Kim, Yoo Jin; Lee, Kwang Woo; Son, Ho Young; Kang, Sung Koo; Kim, Chun Choo; Kang, Moo Il

2006-12-01

154

Changes in bone geometry and microarchitecture caused by intermittent administration of PTH. Comparison with those by exercise load  

International Nuclear Information System (INIS)

There have been several studies showing that periodical intermittent medication with parathyroid hormone (PTH) causes increases in cancellous bone mass. However, there have been almost no reports comparing the effects of periodical intermittent PTH medication on bone microarchitecture with changes caused by physiological stimulation such as exercise load. In this study, we compared the effects of these two interventions on the microarchitecturural deterioration of femoral cancellous bone associated with unloading, using micro-computed tomography (micro-CT), and the effects of PTH administration and motion loading on improvement of the deteriorated structure. In the study, 32 eight-week-old male Wistar rats were divided into four groups: a control group without tail suspension (CON), a control recovery group after suspension (S+C), a suspension/PTH group (S+P), and a suspension/jumping exercise group (S+J). Periodical intermittent human PTH (1-34) was given periodically to the S+P group rats at a dose of 75 ?g/kg/day five times a week for five weeks, after two weeks of exercise with suspension of the tail. The rats in the S+J group performed 40 cm-high jumping 10 times/day five times a week for five weeks. After this conditioning, upon examination, bilateral femurs were removed and the right distal metaphysis was scanned using micro-CT to obtain images of the cancellous bone region of the femur. Based on the tomographic data, indices of cancellous bone microarchitecture was the index of trabecular bone structure were determined by using three-dimensional image analysis system. In addition, to examine the geometric properties of the diaphysis, mid-portion images of the bone shaft of the left femur were obtained by micro-CT, and then the mechanical bone strength of the left femur was determined by performing a three-point bending test. Compared to the S+C group, the S+P and S+J groups showed significantly higher bone volume, bone surface mass values, superficial bone area, bone volume fraction rates, fractal dimensions, connectivity density, trabecular thickness, trabecular bone number and degrees of anisotropy. They conversely showed significantly lower bone volume ratio values, trabecular bone separation, trabecular bone pattern factors, and structural model indices. However, the area values, thickness, and strength of femoral diaphysis cortical bone in the S+J group were significantly higher than those in the S+C group. The S+P group showed no significant difference other than cortical bone thickness. These data suggest that periodical intermittent medication with PTH could cause changes in the fine structure of the femoral metaphysic cancellous bone microarchitecture that are similar to changes caused by jumping exercise, but the effects of PTH seem to be small on the geometric properties and bone strength of the cortical bone. (author)

155

Temperature change in pig rib bone during implant site preparation by low-speed drilling  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: The purpose of this study was to evaluate the temperature change during low-speed drilling using infrared thermography. MATERIAL AND METHODS: Pig ribs were used to provide cortical bone of a similar quality to human mandible. Heat production by three implant drill systems (two convention [...] al drilling systems and one low-speed drilling system) was evaluated by measuring the bone temperature using infrared thermography. Each system had two different bur sizes. The drill systems used were twist drill (2.0 mm/2.5 mm), which establishes the direction of the implant, and finally a 3.0 mm-pilot drill. Thermal images were recorded using the IRI1001 system (Infrared Integrated Systems Ltd.). Baseline temperature was 31±1ºC. Measurements were repeated 10 times, and a static load of 10 kg was applied while drilling. Data were analyzed using descriptive statistics. Statistical analysis was conducted with two-way ANOVA. RESULTS AND CONCLUSIONS: Mean values (n=10 drill sequences) for maximum recorded temperature (Max TºC), change in temperature (?TºC) from baseline were as follows. The changes in temperature (?TºC) were 1.57ºC and 2.46ºC for the lowest and the highest values, respectively. Drilling at 50 rpm without irrigation did not produce overheating. There was no significant difference in heat production between the 3 implant drill systems (p>0.05). No implant drill system produced heat exceeding 47ºC, which is the critical temperature for bone necrosis during low-speed drilling. Low-speed drilling without irrigation could be used during implant site preparation.

Sun-Jong, Kim; Jaeyoung, Yoo; Young-Soo, Kim; Sang-Wan, Shin.

156

Temperature change in pig rib bone during implant site preparation by low-speed drilling  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: The purpose of this study was to evaluate the temperature change during low-speed drilling using infrared thermography. MATERIAL AND METHODS: Pig ribs were used to provide cortical bone of a similar quality to human mandible. Heat production by three implant drill systems (two convention [...] al drilling systems and one low-speed drilling system) was evaluated by measuring the bone temperature using infrared thermography. Each system had two different bur sizes. The drill systems used were twist drill (2.0 mm/2.5 mm), which establishes the direction of the implant, and finally a 3.0 mm-pilot drill. Thermal images were recorded using the IRI1001 system (Infrared Integrated Systems Ltd.). Baseline temperature was 31±1ºC. Measurements were repeated 10 times, and a static load of 10 kg was applied while drilling. Data were analyzed using descriptive statistics. Statistical analysis was conducted with two-way ANOVA. RESULTS AND CONCLUSIONS: Mean values (n=10 drill sequences) for maximum recorded temperature (Max TºC), change in temperature (?TºC) from baseline were as follows. The changes in temperature (?TºC) were 1.57ºC and 2.46ºC for the lowest and the highest values, respectively. Drilling at 50 rpm without irrigation did not produce overheating. There was no significant difference in heat production between the 3 implant drill systems (p>0.05). No implant drill system produced heat exceeding 47ºC, which is the critical temperature for bone necrosis during low-speed drilling. Low-speed drilling without irrigation could be used during implant site preparation.

Sun-Jong, Kim; Jaeyoung, Yoo; Young-Soo, Kim; Sang-Wan, Shin.

2010-10-01

157

Temperature change in pig rib bone during implant site preparation by low-speed drilling  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVES: The purpose of this study was to evaluate the temperature change during low-speed drilling using infrared thermography. MATERIAL AND METHODS: Pig ribs were used to provide cortical bone of a similar quality to human mandible. Heat production by three implant drill systems (two conventional drilling systems and one low-speed drilling system was evaluated by measuring the bone temperature using infrared thermography. Each system had two different bur sizes. The drill systems used were twist drill (2.0 mm/2.5 mm, which establishes the direction of the implant, and finally a 3.0 mm-pilot drill. Thermal images were recorded using the IRI1001 system (Infrared Integrated Systems Ltd.. Baseline temperature was 31±1ºC. Measurements were repeated 10 times, and a static load of 10 kg was applied while drilling. Data were analyzed using descriptive statistics. Statistical analysis was conducted with two-way ANOVA. RESULTS AND CONCLUSIONS: Mean values (n=10 drill sequences for maximum recorded temperature (Max TºC, change in temperature (?TºC from baseline were as follows. The changes in temperature (?TºC were 1.57ºC and 2.46ºC for the lowest and the highest values, respectively. Drilling at 50 rpm without irrigation did not produce overheating. There was no significant difference in heat production between the 3 implant drill systems (p>0.05. No implant drill system produced heat exceeding 47ºC, which is the critical temperature for bone necrosis during low-speed drilling. Low-speed drilling without irrigation could be used during implant site preparation.

Sun-Jong Kim

2010-10-01

158

A case of necrotizing sialomataplasia: consideration on cause, bone change, and incidence  

International Nuclear Information System (INIS)

Necrotizing sialometaplasia (NS) is a rare, benign, self-limiting lesion, but it mimics carcinoma both clinically and histologically. Authors present a case of NS on the right posterior hard palate in a 16-year-old boy. This case showed underlying erosive bone change on CT images. We supposed this lesion resulted from the local anesthesia for dental treatment. Presented NS is the only one case from approximately 1,500 oral and maxillofacial biopsies (0.07%) at Chonnam National University Hospital during the period from 1999 to 2004.

159

Chemical modification of radiation-induced changes in erythroid cells of mouse bone marrow  

International Nuclear Information System (INIS)

Adult male Swiss albino mice were given 20 mg/kg body weight of MGP (2-mercaptopropionylglycine) intraperitoneally 15-30 minutes before 45Ca injection at dose 37 kBq/g body weight. MPG was also administered at various repeated doses. Radioprotective effects of MPG were studied on total erythroid cells (pronormoblasts and normoblasts) at various autopsy intervals (1, 3, 7, 14 and 28 days) posttreatment. It has been observed that MPG in repeated doses is effective in reducing the radiation-induced changes in the erythroid cells of bone marrow in Swiss albino mice following 45Ca internal irradiation. (author)

160

Clonal deletion of self-reactive T cells in irradiation bone marrow chimeras and neonatally tolerant mice. Evidence for intercellular transfer of Mlsa  

International Nuclear Information System (INIS)

Tolerance to Mlsa has been shown to be associated with clonal deletion of cells carrying TCR beta chain variable regions V beta 6 or V beta 8.1 in mice possessing I-E antigens. To evaluate the rules of tolerance induction to Mlsa we prepared irradiation bone marrow chimeras expressing Mlsa or Mlsb and I-E by different cell types. Deletion of V beta 6+, Mlsa-reactive T cells required the presence of Mlsa and I-E products either on bone marrow-derived cells or on irradiated recipient cells. Tolerance was induced when Mlsa and I-E were expressed by distinct cells of the chimera. Also neonatally tolerized mice exhibited depletion of V beta 6+ cells after injection of I-E- Mlsa spleen cells (DBA/1) into newborn I-E+ Mlsb mice (BALB/c x B10.G)F1. These results suggest that the product of the Mlsa locus is soluble and/or may be transferred from cell to cell and bound to I-E antigens. The chimera experiments also showed that tolerance to Mlsa is H-2 allele independent, i.e., is apparently unrestricted. Differentiation of chimeric (H-2d/Mlsa x H-2q/Mlsb)F1 stem cells in either an H-2d or an H-2q thymus revealed that tolerance assessed by absence of V beta 6+ T cells is not dependent on the thymically determined restriction specificity of T cells

 
 
 
 
161

Tc-99m HDP bone scan showing bone changes in a case of tuberous sclerosis or Bourneville's disease.  

Science.gov (United States)

Whole-body Tc-99m HDP scintigraphy was performed in a 25-year-old woman with known tuberous sclerosis. The scintigraphic pattern showed multiple foci of abnormal activity over the hands, phalanges, feet, tibias, fibulas, ulnas, and radii, where radiographs showed periosteal apposition, irregular cortical thickening, and cystlike lesions on the phalanges. The spine, pelvis, and ribs showed heterogeneous tracer uptake where radiographs showed patchy areas of increased bone density. This radiographic pattern is characteristic of osseous tuberous sclerosis. Although previous reports suggested the opposite conclusion, this observation indicates that an abnormal result of bone scintiscan can be observed in osseous tuberous sclerosis. PMID:11139053

Jonard, P; Lonneux, M; Boland, B; Malghem, J; Jamar, F

2001-01-01

162

Competitive ligand exchange reveals mercury reactivity change with dissolved organic matter  

Energy Technology Data Exchange (ETDEWEB)

Abstract Complexation of mercury (Hg) with naturally dissolved organic matter (DOM) is important in freshwater environments but the kinetics of Hg binding to DOM and the repartitioning of Hg within the DOM remain poorly understood. We examined changes in Hg-DOM complexes using glutathione (GSH) titrations, coupled with stannous chloride reducible Hg measurements during Hg equilibration with DOM. In laboratory prepared DOM solutions and in water from a Hg-contaminated creek, a fraction of the Hg that was present in Hg-DOM complexes was not reactive to GSH. This unreactive fraction increased with the reaction time between Hg and DOM. In reactions between Hg and Suwannee River natural organic matter, the unreactive Hg increased from 13% at 1 hour to 74% after 48 hours of equilibration. This time-dependent increase in unreactive Hg suggests that either Hg forms strong complexes with DOM that are unreactive to GSH or the DOM complexed Hg becomes more sterically protected as the binding environment changes within the DOM over time. In the contaminated creek water, 58% of the Hg was present as complexes that were unreactive with GSH, demonstrating that the strength of the Hg-DOM complexes evolves with time. The extent of Hg sequestration inside DOM may provide insight to understanding transformations of Hg in natural aquatic systems.

Miller, Carrie L [ORNL; Gu, Baohua [ORNL; Liang, Liyuan [ORNL

2012-01-01

163

Efficient integration of stiff kinetics with phase change detection for reactive reservoir processes  

DEFF Research Database (Denmark)

We propose the use of implicit one-step Explicit Singly Diagonal Implicit Runge-Kutta (ESDIRK) methods for integration of the stiff kinetics in reactive, compositional and thermal processes that are solved using operator-splitting type approaches. To facilitate the algorithmic development we construct a virtual kinetic cell model. The model serves both as a tool for the development and testing of tailored solvers as well as a testbed for studying the interactions between chemical kinetics and phase behavior. As case study, two chemical kinetics models with 6 and 14 components, respectively, are implemented for in situ combustion, a thermal oil recovery process. Through benchmark studies using the 14 component reaction model the new ESDIRK solvers are shown to improve computational speed when compared to the widely used multi-step BDF methods DASSL and LSODE. Phase changes are known to cause convergence problems for the integration method. We propose an algorithm for detection and location of phase changes based on discrete event system theory. Experiments show that the algorithm improves the robustness of the integration process near phase boundaries by lowering the number convergence and error test failures by more than 50% compared to direct integration without the new algorithm.

Kristensen, Morten Rode; Thomsen, Per Grove

2007-01-01

164

Development of a computer-aided diagnostic scheme for detection of interval changes in successive whole-body bone scans  

International Nuclear Information System (INIS)

Bone scintigraphy is the most frequent examination among various diagnostic nuclear medicine procedures. It is a well-established imaging modality for the diagnosis of osseous metastasis and for monitoring osseous tumor response to chemotherapy and radiation therapy. Although the sensitivity of bone scan examinations for detection of bone abnormalities has been considered to be relatively high, it is time consuming to identify multiple lesions such as bone metastases of prostate and breast cancers. In addition, it is very difficult to detect subtle interval changes between two successive abnormal bone scans, because of variations in patient conditions, the accumulation of radioisotopes during each examination, and the image quality of gamma cameras. Therefore, we developed a new computer-aided diagnostic (CAD) scheme for the detection of interval changes in successive whole-body bone scans by use of a temporal subtraction image which was obtained with a nonlinear image-warping technique. We carried out 58 pairs of successive bone scans in which each scan included both posterior and anterior views. We determined 107 'gold-standard' interval changes among the 58 pairs based on the consensus of three radiologists. Our computerized scheme consisted of seven steps, i.e., initial image density normalization on each image, image matching for the paired images, temporal subtraction by use of the nonlinear image-warping technique, initial detection of interval changes by use of temporal-subtraction images, image feature extraction of candidates of interval changes, rule-based tests by use of 16 image features for removing some false positives, and display of the computer output for identified interval changes. One hundred seven gold standard interval changes included 71 hot lesions (uptake was increased compared with the previous scan, or there was new uptake in the current scan) and 36 cold lesions (uptake was decreased or disappeared) for anterior and posterior views. The overall sensitivity in the detection of interval changes, including both hot and cold lesions evaluated by use of the resubstitution and the leave-one-case-out methods, were 95.3%, with 5.97 false positives per view, and 83.2% with 6.02, respectively. The temporal subtraction image for successive whole-body bone scans has the potential to enhance the interval changes between two images, which also can be quantified. Furthermore, the CAD scheme for the detection of interval changes by use of temporal subtraction images would be useful in assisting radiologists' interpretation on successive bone scan images

165

Changes in bone mineral density and bone turnover markers in obese women after short -term weight loss therapy during a 5-year follow-up  

Directory of Open Access Journals (Sweden)

Full Text Available INTRODUCTION: The protective effect of adipocity on bone metabolism has not been confirmed during long-term follow-up. It is not known whether the rate of bone turnover and changes in mineral metabolism in obese people result from endocrine properties of the adipose tissue or merely the mechanical load. OBJECTIVES: The aim of the study was to evaluate bone and calcium-phosphorus metabolism in obese women during a 5-year follow-up. PATIENTS AND METHODS: The study involved 47 obese women who underwent a 3-month weight loss therapy. We evaluated changes in the serum levels of parathormone (PTH, calcidiol (25(OHD3, collagen type I crosslinked C-telopeptide (CTx-I, osteocalcin, total calcium, inorganic phosphates, and in bone mineral density. The control group consisted of 17 healthy women with proper body weight. RESULTS: We observed a similar decrease in bone mineral density (BMD in the lumbar spine and femoral neck, and a comparable decrease in the serum levels of CTx-I and osteocalcin in both groups during the 5-year follow-up. Changes in serum PTH levels were not statistically significant. In obese women, a nonsignificant increase in the serum level of 25(OHD3 was observed as early as after a 3-month weight loss therapy and during follow-up. In controls, serum 25(OHD3 levels tended to decrease. During follow-up, the number of obese patients with disturbances in vitamin D metabolism decreased from 78.7% to 53.2% (P = 0.01. Such disturbances were observed in 35.3% of the control group. In obese patients, there was a positive correlation between the change in body mass and BMD in the proximal femur (r = 0.279, P = 0.04. In controls, there was a positive correlation between the change in body mass and BMD in the lumbar spine (r = 0.477, P = 0.05. CONCLUSIONS: In obese women who underwent weight loss therapy, the levels of bone turnover markers decreased and abnormal vitamin D metabolism was still observed during the 5-year follow-up.

Jerzy Chudek

2010-07-01

166

Sequential changes in bone marrow architecture during continuous low dose gamma irradiation  

International Nuclear Information System (INIS)

Beagles continuously exposed to low daily doses (10 R) of whole-body 60Co ?-radiation are prone to develop either early occurring aplasstic anemia or late occurring myeloproliferative disorders. In this study, we have examined by a combination of light microscopy and scanning and transmission electron microscopy the sequential changes in the morphology of biopsied rib bone marrow of continuously irradiated dogs that developed either aplastic anemia, myelofibrosis, or myelogenous leukemia. Characteristic modifications of key elements of marrow architecture have been observed during preclinical and clinical phases of these hemopathological conditions. These architectural changes during preclinical phases appear to be related to the pathological progression to each of the radiation-induced hemopathological end points

167

Sequential changes in bone marrow architecture during continuous low dose gamma irradiation  

Energy Technology Data Exchange (ETDEWEB)

Beagles continuously exposed to low daily doses (10 R) of whole-body /sup 60/Co ..gamma..-radiation are prone to develop either early occurring aplasstic anemia or late occurring myeloproliferative disorders. In this study, we have examined by a combination of light microscopy and scanning and transmission electron microscopy the sequential changes in the morphology of biopsied rib bone marrow of continuously irradiated dogs that developed either aplastic anemia, myelofibrosis, or myelogenous leukemia. Characteristic modifications of key elements of marrow architecture have been observed during preclinical and clinical phases of these hemopathological conditions. These architectural changes during preclinical phases appear to be related to the pathological progression to each of the radiation-induced hemopathological end points.

Seed, T.M.; Chubb, G.T.; Tolle, D.V.

1981-01-01

168

Assessing joint effusion and bone changes of the head of the mandible in MR images of symptomatic patients  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of the present study was to investigate the relationship between degenerative bone changes of the head of the mandible and the presence of joint effusion (JE. This study was based on sagittal magnetic resonance imaging (MRI reports of 148 temporomandibular joints (TMJs of 74 patients complaining of pain and/or dysfunction in the TMJ area. The mandible heads were surveyed for osteoarthritis characteristics, which were classified as osteophytosis, sclerosis or erosion. The presence of JE was checked whenever high signal intensity was observed in the articular space. The results evidenced the presence of bone changes in 30% of the sample. Osteophytes and erosions were the changes most commonly observed. JE was reported in 10% of TMJs. The results from the statistical tests revealed that bone changes in the head of the mandible are associated with the presence of JE.

Jefferson Xavier de Oliveira

2013-02-01

169

Assessing joint effusion and bone changes of the head of the mandible in MR images of symptomatic patients  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of the present study was to investigate the relationship between degenerative bone changes of the head of the mandible and the presence of joint effusion (JE). This study was based on sagittal magnetic resonance imaging (MRI) reports of 148 temporomandibular joints (TMJs) of 74 patients comp [...] laining of pain and/or dysfunction in the TMJ area. The mandible heads were surveyed for osteoarthritis characteristics, which were classified as osteophytosis, sclerosis or erosion. The presence of JE was checked whenever high signal intensity was observed in the articular space. The results evidenced the presence of bone changes in 30% of the sample. Osteophytes and erosions were the changes most commonly observed. JE was reported in 10% of TMJs. The results from the statistical tests revealed that bone changes in the head of the mandible are associated with the presence of JE.

Jefferson Xavier de, Oliveira; Jucely Aparecida da, Rosa; Marcelo Eduardo Pereira, Dutra; Karina Cecilia Panelli, Santos; Cibelle, Gil.

170

Oscillator measurements of the reactivity changes resulting from the irradiation of low enrichment particulate fuel in the Dragon reactor  

International Nuclear Information System (INIS)

This Report describes a series of experiments carried out as a joint UKAEA/CEA/DRAGON project to determine the reactivity changes of low-enrichment particulate fuel samples following their irradiation in the DRAGON reactor to various levels up to approximately 60,000 MWD/Te. The samples are described, together with the method of measurement of reactivity in the Winfrith reactor HECTOR, which was an extension of the well-known Oscillator Technique to yield simultaneously overall reactivity changes and changes in macroscopic absorption cross-sections. Measurements were carried out at room temperature in two reactor spectra; a thermal spectrum and one typical of an HTR type reactor. The resultant reactivity changes are presented together with the relevant sample burn-ups as determined by #betta#-scanning methods and, in some cases, by rigorous chemical analysis. The results of supporting measurements are also reported, carried out to characterise the neutron spectra in which the oscillator measurements were made and to determine the neutron flux distributions in the HECTOR reactor. (author)

171

Histomorphometric analysis of the temporal bone after change of direction of force vector of mandible: an experimental study in rabbits  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVES: The present study aimed at performing a histological evaluation of the response of temporal bone tissue to a change of direction of the force vector of the mandible in relation to the base of the skull. MATERIAL AND METHODS: Adult rabbits were assigned into four groups with two control and four experimental animals in each group. experimental animals underwent surgery, which resulted in a change of direction of the force vector on the right temporomandibular joint. Samples were collected after 15, 30, 60 and 90 days for histological analysis. RESULTS: In the two-way analysis of variance, the effect of group and time was statistically significant (p<0.001. Additionally, a statistically significant interaction between group and time was observed (p<0.001. Control animals showed normal growth and development of the temporal region. In the experimental group, the change in direction of the force vector of the mandible induced significant changes in the temporal bone, with a bone modeling process, which suggests growth of this cranial structure. CONCLUSIONS: The methodology used in this experiment allows us to conclude that the change in direction of the force vector of the mandible in relation to the skull base induces remodeling and modeling processes in the temporal bone. The resumption of normal oral functions after bone healing of the mandibular fracture appears to increase cell activation in the remodeling and modeling of the temporal bone structure. The observation of areas of temporal bone modeling shows the relevance of further investigation on the correlation between the joint structures and craniofacial growth and development.

Edela Puricelli

2012-10-01

172

Clinical signs and bone changes associated with phosphorus deficiency in beef cattle.  

Science.gov (United States)

For 10 years, 42 female Herefords (as they progressed from weanling calves to aged cows) were fed diets individually, with phosphorus (P) content being the only variable. During growth and the first 3 gestations, clinically evident differences were not associated with 2 dietary treatments (approx 12 and 38 g of P/day). During the next 2 gestations (2 years), half the cows from each original treatment group were fed less than 6 g of P (n = 21 cows, 11 from the group fed 12 g of P/day and 10 from the group fed 38 g of P/day) daily. The other half were fed diets supplying approximately 8 g of P (n = 11 cows fed 12 g of P/day) and 35 g of P (n = 10 cows fed 38 g of P/day) daily. During the last 3 years of the experiment, all remaining cows were fed diets containing 12 g (n = 19 cows originally fed 12 g) or 19 g (n = 17 cows originally fed 38 g) of P/day. Cows fed diets containing less than 6 g of P/day developed an insidious and subtle complex syndrome characterized by weight loss, rough hair coat, abnormal stance, and lameness. Spontaneous fractures occurred in the vertebrae, pelvis, and ribs. In severely affected cows, fractures did not heal properly. Some bones were demineralized markedly, and the cortical surfaces were porous, chalky white, soft, and fragile. Osteoid tissue was not properly mineralized. Radiography revealed diminished bone density (osteoporosis), cortical thinning, and resorption of trabeculae. Time-related availability of dietary P initiated excessive turnover of bone, with resultant structural changes and impaired function.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3223676

Shupe, J L; Butcher, J E; Call, J W; Olson, A E; Blake, J T

1988-09-01

173

Reactivation-dependent changes in memory states in the terrestrial slug Limax flavus.  

Science.gov (United States)

The change in memory state in the terrestrial slug Limax flavus was studied using cooling-induced retrograde amnesia. Slugs were first conditioned to avoid carrot odor and then a second conditioning procedure was applied 1, 3, 6, or 7 days after the first conditioning trial. Cooling the slugs to approximately 1 degrees C on day 7 immediately after the presentation of the odor used in the conditioning resulted in retrograde amnesia in the slugs that were subject to a second conditioning on day 6 or 7, but not in slugs that were subject to a second conditioning on day 1 or 3. Next, second-order conditioning was used as the second conditioning procedure to distinguish the memory acquired in the first conditioning from that acquired in the second conditioning and similar results were obtained. These results suggest that the reactivation of memory altered the memory state from a cooling-insensitive state to a cooling-sensitive one. A possible model for memory states is discussed. PMID:10706372

Sekiguchi, T; Yamada, A; Suzuki, H

1997-01-01

174

Pore structure and reactivity changes in hot coal gas desulfurization sorbents. Final report, September 1987--January 1991  

Energy Technology Data Exchange (ETDEWEB)

The primary objective of the project was the investigation of the pore structure and reactivity changes occurring in metal/metal oxide sorbents used for desulfurization of hot coal gas during sulfidation and regeneration, with particular emphasis placed on the effects of these changes on the sorptive capacity and efficiency of the sorbents. Commercially available zinc oxide sorbents were used as model solids in our experimental investigation of the sulfidation and regeneration processes.

Sotirchos, S.V.

1991-05-01

175

Zone-dependent changes in human vertebral trabecular bone: clinical implications  

DEFF Research Database (Denmark)

We have previously shown that there are pronounced age-related changes in human vertebral cancellous bone density and microarchitecture. However, the magnitude of these changes seemed to be dependent on zone location in the vertebral body-the central third vs. the areas adjacent to the endplates. The aim of the present study was, therefore, to investigate whether such zone-specific differences could be identified by static histomorphometric measures. The material comprised 48 individuals (24 women aged 19-97 years, and 24 men aged 23-95 years). Three of the women had a known fracture of the L-2. From each L-2, thick frontal sections of half of the vertebra were embedded undecalcified in methylmethacrylate, cut into 10-microm-thick sections, and stained with aniline blue. The sections were scanned into a computer, and classic static histomorphometry was performed on the images. The histomorphometry was performed on both the whole section and on the separate zones (central and sub-endplate zone). The results showed that trabecular bone volume, trabecular number, and connectivity density decreased significantly faster with age, whereas marrow space star volume increased significantly faster with age in the zones adjacent to the endplates than in the central zone. The other histomorphometric measures showed no zone specificity in relation to aging. However, trabecular thickness and trabecular separation were both higher at all ages in the central zone than in the sub-endplate zone, although this was significant only for trabecular separation. The described differences might have significant clinical implications concerning quantitative computed tomography (QCT) scanning, X-ray analyses, and assessment of fracture liability in the human spine, but the underlying pathogenesis is still not known. This study shows that the human vertebral body can be described as two distinct zones with very specific age-related changes in density and microstructure. This zone-specificity is important for the correct interpretation of clinical data.

Thomsen, Jesper Skovhus; Ebbesen, Ebbe Nils

2002-01-01

176

Bone changes in the condylar head and mandibular fossa in patients with temporomandibular disorders. Helical CT observation  

International Nuclear Information System (INIS)

In the present study, we investigated whether bone changes are present in sites impossible to observe by panoramic X-ray and Schuller's X-ray examination, namely the medial of the condylar head and mandibular fossa, in patients with type IV temporomandibular joint disorders. We observed the articular fossa using computed tomography, which is able to obtain detailed 3-dimensional information, in patients with type IV temporomandibular disorders. We examined 120 joints of 60 patiens who visited the Department of Oral Surgery, Osaka Medical College Hospital. Each condylar head was clearly visualized in panoramic X-ray and Schuller's X-ray examination findings, and shown to have possible changes unilaterally. Each joint was diagnosed as type IV, according to the diagnostic guidelines set by Japanese Society for Temporomandibular Joint, and further examined using helical CT. Changes in condylar head; We concluded that bone changes were present with considerable probability in the medial of condylar head in a manner similar to those found in the lateral and center of joints with type IV temporomandibular disorders. Changes in mandibular fossa; The bone changes occurred in various locations of the mandibular fossa, while they appeared significantly more frequently in the condylar head. We think that our finding will contribute to development of treatment strategies for temporomandibular disorders, as they clarify bone changes in sites previously unreported. (author)

177

Changes of serum bone metabolic biochemical markers in elderly subjects with subclinical hypothyroidism  

International Nuclear Information System (INIS)

Objective: To explore the clinical significance of changes of serum bone metabolic biochemical markers levels in elderly subjects with subclinical hypothyroidism. Methods: Serum S-BGP (with RIA), TSH, FT4 (with ECLIA), total cholesterol (TC), triglyceride (TG), HDL, LDL, ApoA1, ApoB and Ca2+ (with biochemical methods) were measured in 30 elderly subjects with subclinical hypothyroidism and 30 controls. Results: The serum levels of S-BGP and calcium in elderly subjects with subclinical hypothyroidism (2.78 ± 0.96 ?g/L and 2.16 ± 0.17 mmol/L respectively) were significantly lower than those in controls (3.9 ± 1.48 ?g/L and 2.31 ± 0.21 mmol/L respectively, both P<0.01). TC and LDL levels in the subclinical hypothyroid subjects (5.58 ± 0.41 mmol/L and 3.67 ± 0.36 mmol/L) were significantly higher than those in controls (P<0.01). Conclusion: The lowering of calcium levels in subjects with subclinical hypothyroidism would lead to loss of bone mass. Decreased S-BGP contents might be the chief cause of osteoporosis in these subjects. (authors)

178

Changes in bone mineral density and body composition during pregnancy and postpartum. A controlled cohort study  

DEFF Research Database (Denmark)

In a controlled cohort study, bone mineral density (BMD) was measured in 153 women pre-pregnancy; during pregnancy; and 0.5, 4, 9, and 19 months postpartum. Seventy-five age-matched controls, without pregnancy plans, were followed in parallel. Pregnancy and breastfeeding cause a reversible bone loss, which, initially, is most pronounced at trabecular sites but also involves cortical sites during prolonged breastfeeding. INTRODUCTION: Conflicting results have been reported on effects of pregnancy and breastfeeding on BMD and body composition (BC). In a controlled cohort study, we elucidate changes in BMD and BC during and following a pregnancy. METHODS: We measured BMD and BC in 153 women planning pregnancy (n?=?92 conceived), once in each trimester during pregnancy and 15, 129, and 280 days postpartum. Moreover, BMD was measured 19 months postpartum (n?=?31). Seventy-five age-matched controls, without pregnancy plans, were followed in parallel. RESULTS: Compared with controls, BMD decreased significantly during pregnancy by 1.8?±?0.5% at the lumbar spine, 3.2?±?0.5% at the total hip, 2.4?±?0.3% at the whole body, and 4.2?±?0.7% at the ultra distal forearm. Postpartum, BMD decreased further with an effect of breastfeeding. At 9 months postpartum, women who had breastfed for

MØller, U K; Við Streym, S

2012-01-01

179

Are alveolar bone changes a determinant factor for "cara inchada" in cattle?  

Directory of Open Access Journals (Sweden)

Full Text Available In order to study possible alterations of the skeleton which might play a role in the pathogenesis of the periodontitis of "cara inchada" in young cattle, ribs from 20 affected calves, 2 to 10 months old, were examined. Electrolytically decalcified longitudinal sections of the costochondral junction and cross sections through the corpus costae, stained with Haematoxylin-Eosin, were studied. In five calves, longitudinal sections of the proximal humerus were examined as well. The status of mineralization was checked by microradiograms. Systemic alteration of the skeleton due to disturbances of mineral metabolism could not be shown in any of the animals. In seven 2 to 4 months old calves, no bone changes were found. The reduced osteogenesis in six 3 to 5 months old calves and the reduced osteogenesis and diminished chondral growth in seven 5 to 10 months old calves are therefore a consequence of the disease. The results show that the development of the alveolar bone was not defective, so this cannot be a determinant factor for the development of the periodontitis of "cara inchada" in cattle.

Döbereiner Jürgen

1997-01-01

180

Graft-versus-host reaction and immune function. III. Functional pre-T cells in the bone marrow of graft-versus-host-reactive mice displaying T cell immunodeficiency  

International Nuclear Information System (INIS)

Studies were performed to determine whether pre-T cells develop normally in the bone marrow of mice displaying thymic dysplasia and T cell immunodeficiency as a consequence of a graft-versus-host (GVH) reaction. GVH reactions were induced in CBAxAF1 mice by the injection of A strain lymphoid cells. To test for the presence of pre-T cells in GVH-reactive mice, bone marrow from GVH-reactive mice (GVHBM) was injected into irradiated syngeneic F1 mice and 30-40 days later thymic morphology and function were studied. Morphology studies showed nearly normal thymic architectural restoration; moreover, such glands contained normal numbers of Thy-1-positive cells. Functional pre-T cells were evaluated by transferring thymocytes from the irradiated GVHBM-reconstituted mice into T-cell-deprived mice. These thymocytes reconstituted allograft reactivity, T helper cell function and Con A and PHA mitogen responses of T-cell-deprived mice. These results suggest that the pre-T cell population in the bone marrow is not affected by the GVH reaction. Therefore, the T cell immunodeficiency associated with the GVH reaction is not due to a deficiency of pre-T cells in the bone marrow but is more likely associated with GVH-induced thymic dysplasia

 
 
 
 
181

Graft-versus-host reaction and immune function. III. Functional pre-T cells in the bone marrow of graft-versus-host-reactive mice displaying T cell immunodeficiency  

Energy Technology Data Exchange (ETDEWEB)

Studies were performed to determine whether pre-T cells develop normally in the bone marrow of mice displaying thymic dysplasia and T cell immunodeficiency as a consequence of a graft-versus-host (GVH) reaction. GVH reactions were induced in CBAxAF1 mice by the injection of A strain lymphoid cells. To test for the presence of pre-T cells in GVH-reactive mice, bone marrow from GVH-reactive mice (GVHBM) was injected into irradiated syngeneic F1 mice and 30-40 days later thymic morphology and function were studied. Morphology studies showed nearly normal thymic architectural restoration; moreover, such glands contained normal numbers of Thy-1-positive cells. Functional pre-T cells were evaluated by transferring thymocytes from the irradiated GVHBM-reconstituted mice into T-cell-deprived mice. These thymocytes reconstituted allograft reactivity, T helper cell function and Con A and PHA mitogen responses of T-cell-deprived mice. These results suggest that the pre-T cell population in the bone marrow is not affected by the GVH reaction. Therefore, the T cell immunodeficiency associated with the GVH reaction is not due to a deficiency of pre-T cells in the bone marrow but is more likely associated with GVH-induced thymic dysplasia.

Seddik, M.; Seemayer, T.A.; Lapp, W.S.

1986-02-01

182

MRI manifestations of bone marrow changes after recombinant human granulocyte colony stimulating factor was subcutaneous for healthy adults  

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Objective: To investigate MRI manifestations of lumbar and proximal femoral bone marrow changes before and after recombinant human granulocyte colony stimulating factor (rhG-CSF) was subcutaneous injected for healthy adults. Methods: Twenty healthy blood stem cell donors without hematologic disease were enrolled in this study. All of them underwent lumbar sagittal and proximal femur coronal MRI examination with spin echo T1WI and fat-suppressed T2WI. The first examination were performed before subcutaneous injection of rhG-CSF for comparison. In 4-7 days and 30-60 days after injection, the other two examinations were performed. The signal changes of lumbar and proximal femoral bone marrow were investigated by reading pictures and calculating the contrasted noise ratio (CNR). Results: Before rhG-CSF injection, all patients presented normal signal intensity of bone marrow. In 4- 7 days after injection, all the 20 cases presented homogeneous signal decrease in lumbar vertebral bodies on T1WI, accompanied by reduced fatty signal. In proximal femur, patchy or stripped hypointensity areas were found in intertrochanteric and subtrochanteric areas on T1WI. On fat-suppressed T2WI images, the signal of' lumbar and proximal femoral bone marrow changed to equal or slightly-high signal intensity. In all cases, abnormal signal areas presented in lumbar and proximal femoral bone marrow occurred simultaneously in the same case. In the 10 cases received the third MRI during 30-60 days after rhG-CSF injection, signal intensity of lumbar bone marrow turned to normal in all sequence, but abnormal signal intensity areas were still existed and extended to distal part in femoral bone marrow, which appeared as symmetric stripped or patchy equal or slightly-low signal intensity on T1WI and equal or slightly-high signal intensity on T2WI. The CNR of lumbar bone marrow to subcutaneous fat before rhG-CSF injection, in 4-7 days and 30-60 days after rhG-CSF injection were 114.11±15.11, 71.04±12.25 and 91.64±11.68, respectively. Significant difference was found between before rhG-CSF injection and 4-7 days after injection (P0.05). Conclusion: After injection of rhG-CSF, the short- term changes of hematopoietic cells and fat content in bone marrow can be displayed on MRI, which provided non-invasive information for bone marrow transplantation. (authors)

183

Changes of porous poly(?-caprolactone) bone grafts resulted from e-beam sterilization process  

International Nuclear Information System (INIS)

The most important mechanical feature of poly(?-caprolactone) (PCL) foams applied in bone tissue engineering as a scaffold, has been investigated as a function of irradiation dose. Radiation is proposed for the sterilization of the polymer before the implantation. Polycaprolactone scaffold foams were obtained by combination of compression molding and particulate leaching techniques. The porogen was changed in the range 74-96 w% and the irradiation dose was varied from 25 to 150 kGy. Our results show that yield strength is not a function of radiation dose, but is rather influenced by the porosity, while the critical strain is mainly dependent on the dose. All these together mean that the modulus of the elasticity of PCL foams is dependent on both the porosity and the dose

184

Change in bone mass after Colles' fracture: a case report on unique data collection and long-term implications.  

Science.gov (United States)

The cast immobilization of a fractured limb results in a loss of bone mass; however, the long-term implications of that effect with regard to bone mineral status, particularly in other skeletal sites, are less known. The purpose of this study was to describe changes in bone mass in different skeletal sites triggered by Colles' fracture. The case is unique regarding the existence of baseline measurements taken just a few days before the fracture on all measurable skeletal sites, including the fractured radius. Therefore, it was also possible to determine whether the injury caused long-term bone loss in the affected and unaffected skeletal sites. The patient was a healthy, premenopausal Caucasian woman, in her late forties, who fractured her nondominant wrist as a result of low-impact fall on ice. The arm and the metacarpals were immobilized to the elbow for 5 wk. Bone mass measurements were performed with DPX-MD densitometer (Lunar Corp. Madison, WI) at baseline and 5, 10, 13, 21, and 52 wk postinjury. At the 5-wk measurement (on plaster removal) there was a notable increase in bone mineral density (BMD) and bone mineral content (BMC) in all sites of ulna and radius of the injured forearm (from 10 to 73%), followed by the apparent decline to or below the baseline at 10, 13, 21 and 52 wk of follow-up. Other skeletal sites were measured at 10 wk when a substantial decrease in BMD and BMC in some of the hip regions and lumbar spine was noticed; most notably in L3-L4, Ward's triangle, and femoral neck (from 2 to 8%) and remained such after 1 yr. Although this patient had a normal bone mineral status and no osteopenia detected before fracture, the trauma of radial fracture caused long-standing bone loss in fracture-prone areas-hip and spine. Because about 70% of bone strength is explained by its mineral density, the patient might be at increased risk for fracture later in life. The changes in bone mass after injury should be monitored and interpreted carefully, and more elaborate treatment of patients presenting with wrist fractures are needed to prevent any potential risk for later osteoporotic fractures in spine and hip and possible refracture of the injured extremity. PMID:11175919

Ilich, J Z; Zito, M; Brownbill, R A; Joyce, M E

2000-01-01

185

Bone Mineral Changes and Cardiovascular Effects among Female Athletes with Chronic Menstrual Dysfunction  

Science.gov (United States)

Purpose Oligo/amenorrhea, as a part of the Female Athlete Triad has adverse effects on the athlete's bone mineral density (BMD) and cardiovascular system. Hypoestrogenism, due to suppression of hypothalamus-pituitary axis (HPA) as a result of energy imbalance, is the possible cause of the Triad. This study was designed based on following up and reassessment of elite female athletes who were diagnosed as menstrual dysfunction about two years ago. Methods This study was conducted in three phase sections: 1) Reassess the pattern of menstrual cycle among athletes who reported menstrual dysfunction about two years ago; 2) Bone mineral density was measured twice in the same machine and same center with a two-year interval; 3) The laboratory data including blood glucose, lipid profile and inflammatory markers was assessed in phase 3. Results BMD of athletes did not change significantly after 25.5 months of oligomenorrhea P (spine) = 0.2, P (femur)=0.9. Mean of all cardiovascular factors was in the normal range except for high density lipoprotein (HDL) which was 49.28 (SD=9.18), however, most of the athletes had abnormalities in their lipid profile. Inverse relationship between the increase in the BMD of spine and total cholesterol (r =?0.49, P=0.04), Apolipoprotein A (r = ?0.51 P=0.04), and very low density lipoprotein (VLDL) (r =?0.66, P=0.009). Also correlation between BMD of spine and HbA1C (r =?0.70, P=0.003) were significant. Conclusion Findings of this study show that negative changes in BMD and cardiovascular biomarkers of female athletes with functional hypothalamic menstrual dysfunction could occur if proper therapeutic intervention (including increase in calorie intake, decrease in exercise load or hormonal replacement) will not consider. PMID:22461966

Soleimany, Ghazaleh; Dadgostar, Haleh; Lotfian, Sara; Moradi-Lakeh, Mazyar; Dadgostar, Elham; Movaseghi, Shafieh

2012-01-01

186

Age-related changes in the plasticity and toughness of human cortical bone at multiple length-scales  

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The structure of human cortical bone evolves over multiple length-scales from its basic constituents of collagen and hydroxyapatite at the nanoscale to osteonal structures at nearmillimeter dimensions, which all provide the basis for its mechanical properties. To resist fracture, bone’s toughness is derived intrinsically through plasticity (e.g., fibrillar sliding) at structural-scales typically below a micron and extrinsically (i.e., during crack growth) through mechanisms (e.g., crack deflection/bridging) generated at larger structural-scales. Biological factors such as aging lead to a markedly increased fracture risk, which is often associated with an age-related loss in bone mass (bone quantity). However, we find that age-related structural changes can significantly degrade the fracture resistance (bone quality) over multiple lengthscales. Using in situ small-/wide-angle x-ray scattering/diffraction to characterize sub-micron structural changes and synchrotron x-ray computed tomography and in situ fracture-toughness measurements in the scanning electron microscope to characterize effects at micron-scales, we show how these age-related structural changes at differing size-scales degrade both the intrinsic and extrinsic toughness of bone. Specifically, we attribute the loss in toughness to increased non-enzymatic collagen cross-linking which suppresses plasticity at nanoscale dimensions and to an increased osteonal density which limits the potency of crack-bridging mechanisms at micron-scales. The link between these processes is that the increased stiffness of the cross-linked collagen requires energy to be absorbed by “plastic” deformation at higher structural levels, which occurs by the process of microcracking.

Zimmermann, Elizabeth A.; Schaible, Eric; Bale, Hrishikesh; Barth, Holly D.; Tang, Simon Y.; Reichert, Peter; Busse, Bjoern; Alliston, Tamara; Ager III, Joel W.; Ritchie, Robert O.

2011-08-10

187

Multiscale modeling of porosity, permeability, diffusivity and reactive surface changes during dissolution.  

Science.gov (United States)

Meshed models in which equations are solved assuming that constant effective macroscopic properties can be defined in each cells are essential tools for predicting reservoir properties changes triggered by mineral dissolution (or precipitation) due to CO2 injection. However, the parameterization of the dissolution-precipitation problem and their feedback effects on the flow field are still challenging. The problem arises from the mismatch between the scales at which averaged parameters and parameters relationships (such as the porosity-permeability heuristic relation) are defined and the scale at which chemical reactions occur according to the pore scale fluid concentration and flow heterogeneities and modify the pore network geometry. Here, we investigate the links between the dissolution mechanisms that control the porosity changes and the related changes of the effective macroscopic value of the reactive surface area, permeability and diffusivity (or diffusional tortuosity) by means of numerical modeling at pore scale. The porous structure (pore space and mineral matrix) is spatially discretized in voxels. It is issued from either numerical generation or from processed X-ray microtomography images. Flow, reactant transport and matrix dissolution is modeled by solving iteratively the Stokes equation with no-slip boundary condition at the rock-pore interface and the advection-diffusion equation using Time Domain Random Walk (TDRW). In the examples presented here, the reaction is a first order kinetic dissolution reaction which allows a simple parameterization of the problem using the average Peclet and the Damkohler numbers characterizing the local diffusion-to-advection and the reaction-to- advection characteristic times. Depending on these parameters that are related to the reactant concentration, the reaction kinetic and the macroscopic pressure drop across the domain, effective relations between the porosity, permeability and diffusivity are obtained, showing a large range of behavior that can be directly compared to those obtained from laboratory scale experiments. The results emphasize the large influence of the initial heterogeneity. In the case of heterogeneous dissolution, i.e. when mass transfer localization occurs and heterogeneity is created by the dissolution itself (for example for high Da values) the effective parameters are scale dependent and cannot be used directly in macroscale models.

Sadhukhan, S.; Gouze, P.; Dentz, M.; Dutta, T.

2012-04-01

188

Reactivity changes in hybrid thermal-fast reactor systems during fast core flooding  

International Nuclear Information System (INIS)

A new space-dependent kinetic model in adiabatic approximation with local feedback reactivity parameters for reactivity determination in the coupled systems is proposed in this thesis. It is applied in the accident calculation of the 'HERBE' fast-thermal reactor system and compared to usual point kinetics model with core-averaged parameters. Advantages of the new model - more realistic picture of the reactor kinetics and dynamics during local large reactivity perturbation, under the same heat transfer conditions, are underlined. Calculated reactivity parameters of the new model are verified in the experiments performed at the 'HERBE' coupled core. The model has shown that the 'HERBE' safety system can shutdown reactor safely and fast even in the case of highly set power trip and even under conditions of big partial failure of the reactor safety system (author)

189

Calcium phosphate crystal forms in human jaw bones of changed osteoporotic structure  

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Full Text Available Introduction. Calcium phosphates are chemical compounds that can be found in various forms within nature, as well as in human jaws and bones. The aim of this study was to assess the structure of solid chemical compounds which form the structure of normal and osteoporotic jaw-bones. Materials and Methods. The jaw-bones taken from human cadavers were used in the study. Crystalographic forms of calcium phosphate, in the samples of human jaw-bone, were determined using X-ray diffraction technique. The experimental bone samples originated from osteoporotic jaw-bone of cadavers while control samples were taken from dentate jaw-bones of non-osteoporotic cadavers. Results. The results of this study showed that hydroxyapatite was the only phase determined in control non-osteoporotic bone samples. In experimental (osteoporotic bone samples, the same phase was registered, as well as calcium monophosphate and hydrated calcium phosphate, registered as increments of values on ? axis. Conclusion. Hydroxyapatite was the only compound detected in normal bone while osteoporotic bone contained others crystallographic forms of calcium phosphates.

Pošti? Sr?an D.

2011-01-01

190

Study of irradiated bone: Part III. /sup 99m/Tc pyrophosphate autoradiographic changes  

International Nuclear Information System (INIS)

The macroautoradiographic and microautoradiographic localization of /sup 99m/Tc-pyrophosphate (/sup 99m/TcPPi) was studied in x-irradiated bone of rabbits up to one year post-irradiation. In cortical bone, /sup 99m/TcPPi was concentrated on bone surfaces near vasculature. Both forming and resorbing bone surfaces were comparably labeled at 2 hrs post-injection. Uptake on the surface of sites of haversian bone remodeling was observed to be at least part of the increased /sup 99m/TcPPi observed in irradiated bone in camera images. In irradiated trabecular bone 12 months following irradiation, a patchy decrease in /sup 99m/TcPPi uptake was correlated with localized decreases in vasculature

191

Early bone changes after incorporation of low quantities of alpha emitters in male rats  

International Nuclear Information System (INIS)

This work shows the early effects of cancergenic doses of alpha emitters in long bones of rats. The investigations were based on radiographic, morphologic, angiographic, histologic and electronmicroscopic methods. A special method for bone angiography in the rat was elaborated and a new method was developed for measurement of the femur neck-head angle. Numerous disturbances in bone growth and bone structure, in the blood supply of bone and also of the bone building cells were observed. There was a correlation between the severity of the damage and the radiation dose, the spacial distribution of the nuclide and partially the age of the rats. The bone injury due to plutonium was markedly reduced by administration of the chelating agent Zn-DTPA. (orig.)

192

Changes in human bone marrow fat content associated with changes in hematopoietic stem cell numbers and cytokine levels with aging.  

Science.gov (United States)

Hematological deficiencies increase with aging, including anemias, reduced responses to hematopoietic stress and myelodysplasias. This investigation tested the hypothesis that increased bone marrow (BM) fat content in humans with age was associated with decreased numbers of side population (SP) hematopoietic stem cells, and this decrease correlated with changes in cytokine levels. BM was obtained from the femoral head and trochanteric region of the femur removed at surgery for total hip replacement (N = 100 subjects). In addition, BM from cadavers (N = 36), with no evidence of hip disease, was evaluated for fat content. Whole trabecular marrow samples were ground in a sterile mortar and pestle, and cellularity and lipid content determined. Marrow cells were stained with Hoechst dye and SP profiles were acquired. Plasma levels of insulin-like growth factor (IGF)-1, stromal-derived factor (SDF)-1 and interleukin (IL)-6 were measured using ELISA. Fat content in the BM of human subjects and cadavers increased with age. The numbers of SP stem cells in BM as well as plasma IGF-1 and SDF-1 levels decreased in correlation with increased BM fat. IL-6 had no relationship to changes in marrow fat. These data suggest that increased BM fat may be associated with a decreased number of SP stem cells and IGF-1 and SDF-1 levels with aging. These data further raise a more general question as to the role of adipose cells in the regulation of tissue stem cells. PMID:21923862

Tuljapurkar, Sonal R; McGuire, Timothy R; Brusnahan, Susan K; Jackson, John D; Garvin, Kevin L; Kessinger, Margaret A; Lane, Judy T; O' Kane, Barbara J; Sharp, John G

2011-11-01

193

Sequential changes in bone marrow architecture during continuous low dose gamma irradiation  

International Nuclear Information System (INIS)

Beagles continuously exposed to low daily doses (10 R) of whole-body 60Co gamma-radiation are prone to develop either early occurring aplastic anemia or late occurring myeloproliferative disorders (Seed et al., 1977). In this study, we have examined by a combination of light microscopy and scanning and transmission electron microscopy the sequential changes in the morphology of biopsied rib bone marrow of continuously irradiated dogs that developed either aplastic anemia, myelofibrosis, or myelogenous leukemia. Characteristic modification of key elements of marrow architecture have been observed during preclinical and clinical phases of these hemopathological conditions. The more prominent of these changes include the following. (i) In developing aplastic anemia: severe vascular sinus and parenchymal cord compression, and focally degenerate endosteal surfaces. (ii) In developing myelofibrosis: hyperplasia of endosteal and reticular stomal elements. (iii) In developing leukemia: hypertrophy of reticular and endothelial elements in the initial restructuring of the stromal matrix and the subsequent aberrant hemopoietic repopulation of the initially depleted stromal matrix. These architectural changes during preclinical phases appear to be related to the pathological progression to each of the radiation-induced hemopathological end points

194

Sequential changes in bone marrow architecture during continuous low dose gamma irradiation  

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Beagles continuously exposed to low daily doses (10 R) of whole-body 60Co gamma-radiation are prone to develop either early occurring aplastic anemia or late occurring myeloproliferative disorders (Seed et al., 1977). In this study, we have examined by a combination of light microscopy and scanning and transmission electron microscopy the sequential changes in the morphology of biopsied rib bone marrow of continuously irradiated dogs that developed either aplastic anemia, myelofibrosis, or myelogenous leukemia. Characteristic modification of key elements of marrow architecture have been observed during preclinical and clinical phases of these hemopathological conditions. The more prominent of these changes include the following. (i) In developing aplastic anemia: severe vascular sinus and parenchymal cord compression, and focally degenerate endosteal surfaces. (ii) In developing myelofibrosis: hyperplasia of endosteal and reticular stomal elements. (iii) In developing leukemia: hypertrophy of reticular and endothelial elements in the initial restructuring of the stromal matrix and the subsequent aberrant hemopoietic repopulation of the initially depleted stromal matrix. These architectural changes during preclinical phases appear to be related to the pathological progression to each of the radiation-induced hemopathological end points.

Seed, T.M.; Chubb, G.T.; Tolle, D.V.

1981-01-01

195

A radiographic evaluation of progressive loading on crestal and bone density changes around single osseointegrated implants in the posterior maxilla  

Directory of Open Access Journals (Sweden)

Full Text Available "nBackground and Aim: The aim of this clinical study was to determine the effectiveness of progressive loading procedures on preserving crestal bone height and improving peri-implant bone density around maxillary implants restored with single crowns by an accurate longitudinal radiographic assessment technique. "n "n "nMaterials and Methods: Eleven Micro-Thread Osseo Speed dental implants were placed in 11 subjects and permitted to heal for 6 weeks before surgical uncovering. Following an 8-week healing period, implants underwent a progressive loading protocol by increasing the height of the occlusal table in increments from adding acrylic resin to an acrylic crown. The progressively loaded crowns were placed in 2 mm infraocclusion for the first 2 months, light occlusion for the second 2 months, and full occlusion for the third 2 months. At forth 2 months, a metal ceramic crown replaced the acrylic crown. Digital radiographs of each implant were made at the time of restoration, then after 2, 4, 6, 8, and 12 months of function. Digital image analysis was done to measure changes in crestal bone height and peri-implant bone density. "n "n "nResults: The mean values of crestal bone loss at 12 months were 0.11 ± 0.19 mm, and when tested with Friedman across the time periods, the differences were not statistically significant (p> 0.05. The mean values of bone density in the crestal, middle, and apical area were tested with Repeated Measure ANOVA across the time periods, the differences were statistically significant (p<0.05. "n "n "nConclusion: Progressive loading doesn’t cause crestal bone loss. The peri-implant density measurements of the progressively loaded implants show continuous increase in crestal, middle and apical peri-implant bone density by time. "n 

Ommati Shabestari Gh.

2009-11-01

196

Evaluation of MR spectroscopy and diffusion-weighted MRI in detecting bone marrow changes in postmenopausal women with osteoporosis  

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Aim: To prospectively investigate the role of MR spectroscopy (MRS) and diffusion-weighted magnetic resonance imaging (DWI) in assessing vertebral marrow changes in postmenopausal women with osteoporosis. Materials and methods: Seventy-eight postmenopausal women (mean age 63.7 +- 3.5 years; range 55-81 years), who underwent dual-energy x-ray absorptiometry of the spine, were divided into three bone density groups (24 with normal, 25 with osteopaenic, and 29 with osteoporotic) based on T score. Both MRS and DWI of the L3 vertebral body were performed to calculate the marrow fat content and apparent diffusion coefficient (ADC). The results were compared between three groups and correlated with BMD. Results: Vertebral marrow fat content was significantly increased in the osteoporotic group (59.97 +- 5.78%), when compared with that of the osteopaenic group (53.04 +- 7.66%, p = 0.001) and the normal bone density group (48.79 +- 7.1%, p < 0.001). ADC values in the osteoporotic, osteopaenic, and normal bone density groups were 0.39 +- 0.02 x 10{sup -3} mm{sup 2}/s, 0.41 +- 0.02 x 10{sup -3} mm{sup 2}/s, and 0.47 +- 0.03 x 10{sup -3} mm{sup 2}/s, respectively, with statistically significant difference (P < 0.001). A statistically significant positive correlation between T scores and ADC existed (r = 0.835, p < 0.001). The vertebral marrow fat content was negatively correlated to the bone density (r = -0.639, p < 0.001) and to marrow ADC (r = -0.554, p < 0.001). Conclusion: The postmenopausal women with osteoporosis exhibited a corresponding increase in vertebral marrow fat content as the bone density decreased. Marrow fat content and ADC were related to the bone density. MRS and DWI are helpful in evaluating the bone marrow changes in postmenopausal women.

Tang, G.Y., E-mail: tgy17@126.co [Department of Radiology, Affiliated Tenth People' s Hospital of Tongji University, Shanghai 200072 (China); Lv, Z.W.; Tang, R.B.; Liu, Y.; Peng, Y.F.; Li, W.; Cheng, Y.S. [Department of Radiology, Affiliated Tenth People' s Hospital of Tongji University, Shanghai 200072 (China)

2010-05-15

197

Mechanistic investigations on the etiology of Risperdal® Consta®-induced bone changes in female Wistar Hannover rats  

International Nuclear Information System (INIS)

RISPERDAL® CONSTA® is a long-acting, intramuscular formulation of risperidone microspheres for the biweekly treatment of schizophrenia and other psychiatric disorders. In a 24-month carcinogenicity study male and female Wistar Hannover rats received RISPERDAL® CONSTA® by intramuscular injection at dosages of 5 or 40 mg/kg once every 2 weeks. Bone changes described as “osteodystrophy” were observed by routine microscopic examination at 40 mg/kg in the sternum of female rats after 12 months, and in the sternum and stifle joint of both male and female rats after 24 months of treatment, respectively. To investigate the etiology of these bone changes, a 12-month mechanistic study was conducted in female Wistar Hannover rats at dosages of 5, 20 and 40 mg/kg once every 2 weeks. In addition to routine parameters, this study included bone markers, hormone measurements, and peripheral quantitative computed tomography (pQCT) and dual-energy X-ray absorptiometry (DXA) bone density measurements. It revealed a treatment-related reduction in metaphyseal trabecular bone density of the femur and tibia at 20 and 40 mg/kg, which was evident in the tibia from Week 13 of treatment onwards. There was no convincing evidence for any of the modes of action known to underlie trabecular bone loss in rats including renal, nutritional, or hepatic osteodystrophy, estrogen deficiency, hyperthyroidism or glucocorticoid excess. It is hypothetized that prolonged hyperprolactinemia accompanied by an increase in parathyroid hormone-related protein (PTHrP) levels and a slight hypoestrogenic state could have caused the reduced trabecular bone density in RISPERDAL® CONSTA®-treated rats. The relevance of this finding in terms of human risk is unknown.

198

Measurement of reactivity change with temperature of single fuel rod using coated particles  

International Nuclear Information System (INIS)

Reactivity decrease with temperature rise of a single coated-particle fuel rod was measured in a SHE-14 core using a heating apparatus, to verify the core design accuracy of High Temperature Experimental Reactor. The coated-particle fuel rod was made by inserting 4% enriched uranium coated-particle fuel pellets into a silica sleeve. The rod was then inserted into a heating tube of the heating apparatus, which was placed along the central axis of the SHE-14 core. The measured reactivity decrease for the single coated-particle fuel rod, minus the reactivity decrease graphite rod of same form, can be interpreted to originate only in the increased resonance neutron capture rate of 238U by Doppler effect. The measured reactivity decrease is in excellent agreement with the calculated value by multi-group perturbation theory taking into account only the increased effective resonance integral of 238U estimated using the resonance parameter of ENDF/B-3. It is concluded, therefore, that calculation of Doppler reactivity coefficient using the resonance parameters is very accurate for Very High Temperature Experimental Reactor using coated-particle fuel. (author)

199

Bone marrow transplantation controlling hormonal and structural changes in radiation exposed pregnant mice and their developing embryos  

International Nuclear Information System (INIS)

Ascending doses of whole body gamma irradiation delivered at different gestational stages of mouse exposed to 1 and 2 Gy gamma rays fractionated at 1 Gy installments and possible curative role of bone marrow transplantation has been studied. The results confirmed the impairment of the levels of the two maternal hormones 17 estradiol and progesterone besides histopathological changes in the skin, heart and skeleton at different embryonic stages. 17 Beta estradiol level was not changed significantly in mice treated with 1 Gy and fractionated 2 Gy. Bone marrow treatment remarkably restored its level. Animals subjected to the dose level 1 Gy exhibited a slight decrease in the progesterone level while a significant drop in the hormone level was noticed upon irradiation at 2 Gy. Bone marrow transplantation provided little repair for the hormone. Treatment with bone marrow transplantation, was effective in alleviating the histopathological changes due to the lower dose (One Gy), yet it had less pronounced recovery of defects produced by the higher irradiation dose

200

Anodic reactivity of ferrous sulfide precipitates changing over time due to particulate speciation.  

Science.gov (United States)

The disposal of ferric phosphate (FePO4) sludge, routinely generated in wastewater and drinking water treatment, has a major impact on the overall treatment cost. Iron sulfide (FeSx) precipitation via sulfide addition to ferric phosphate (FePO4) sludge has been proven to be an effective method for phosphate recovery. Electrochemical oxidation of FeSx can then be utilized to recover ferric iron for reuse back in the phosphate removal process. In this study, the reactivity of FeSx particles for anodic oxidation at pH 4 was studied as a function of time after FeSx precipitate generation at a S/Fe molar ratio of 1.75. Cyclic voltammetry showed high reactivity for fresh FeSx particles, but the reactivity diminished significantly over a period of 1 month. X-ray absorption spectroscopy (XAS) revealed that this reduced reactivity with time is a consequence of the transformation of the FeSx particles in suspension from mackinawite (FeS) to pyrite (FeS2). PMID:24093133

Mejia Likosova, Elena; Collins, Richard N; Keller, Jurg; Freguia, Stefano

2013-11-01

 
 
 
 
201

Some peculiarities of ultrastructural changes of bone marrow myeloid and erythroid sprouts of rats in acute radiation injury  

International Nuclear Information System (INIS)

Changes in rat bone marrow tissue in 3,7,14,21 and 28 days after 750 R irradiation have been studied by electron microscopy. Deep injuries in ultrastructure of cells of myeloid and erythroid sprouts of bone marrow have been established. A more intensive macrophage reaction leading to the bone marrow cleaning from destructing cells results from the reconstruction of reticular cells. Myeloid cells are destructed due to their ultrastructures disintegration, while erythroid cells - due to pyknosis. Maximum injury of erythroid sprout cells is noted during the period of the most pronounced recovery in a myeloid sprout. These regularities point to the necessity of special measures to stimulate red hematopoiesis during the period of its greatest injury

202

The Effect of Feeding Purified versus Chow Diet on Bone Changes Produced by Hindlimb Suspension of Female Rats  

Science.gov (United States)

Spaceflight simulation studies use chow diets while spaceflight studies use a semi-purified &et. To determine whether the differences in these diets would affect the changes in unweighted bone, we compared the effects of purified vs chow diet on bone parameters, urinary calcium, plasma estradiol, and urinary corticosterone (CORT) in sexually mature female Sprague-Dawley rats. Rats fed purified AIN-93G or chow diet were kept ambulatory (AMB) or subjected to a spaceflight simulation model of unweighted hindlimbs (HLS) for 38 days. Body mass of treatment groups was similar although food intake and caloric density of the diets differed. Both HLS diet groups showed similar decreases in bone mineral content and mechanical strength in unweighted femurs compared to AMB (pfemur length was lower (pFemur mineral content was related to plasma estradiol (r(sup 2) =0.91, p<0.00l). Urinary CORT excretion was increased during initial HLS and elevated in HLS/chow-fed rats. Diets did not appear to affect the osteopenia induced by unweighting, but effects on bone growth, calcium excretion, plasma estradiol and urinary CORT do not support the view that these diets can by used interchangeably in bone studies.

Tou, Janet; Arnaud, Sara B.; Grindeland, Richard; Wade, Charles

2004-01-01

203

The imaging features of surrounding changes caused by bone tumors and tumor-like lesions  

International Nuclear Information System (INIS)

Objective: To explore the imaging features of bone marrow edema (BME) and soft tissue edema (STE) caused by bone tumors and tumor-like lesions. Methods: Ninety nine patients with bone tumors and tumor-like lesions which were proved by surgical pathology were reviewed. The patients were divided into benign and malignant groups. Evaluation parameters included the size and signal intensity of BME and STE, the features of enhancement, the bone sclerosis and its relation with BME, and joint effusion, et al. The data of two groups were analyzed by ?2 test. Results: There were 40 patients in benign group and 59 patients belonged to malignant group. BME and STE demonstrated low signal on T1-weighted images and high signal on fat-suppressed T2-weighted images. Some BMEs demonstrated low signal on T2- weighted images, which corresponded to sclerosis on X-ray film and (or) CT. Both BME and STE demonstrated uniform enhancement. There were statistically significant differences between benign and malignant groups including the frequency of BME, sclerosis, the median of the size of the BME and STE (P0.05). Conclusions: Both benign bone tumors and tumor-like lesions and malignant bone tumors can be accompanied by BME and STE. The size of BME in the benign bone tumors and tumor-like lesions is bigger than those in malignant ones, and the size of STE in malignant bone tumors is bigger than benign ones. (authors)

204

Polarization-Correlation Analysis of Anisotropic Structures in Bone Tissue for the Diagnostics of Pathological Changes  

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A method for the correlation analysis of polarization-filtered laser images of bone tissue is considered. Its ability to visualize the bone-tissue multifractal network in its normal and pathological states is analyzed. A set of criteria for the optical diagnostics of osteoporosis is determined.

Angel'Ski?, O. V.; Ushenko, A. G.; Burkovets, D. N.; Ushenko, Yu. A.

2001-03-01

205

Evaluation of MR spectroscopy and diffusion-weighted MRI in detecting bone marrow changes in postmenopausal women with osteoporosis  

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Aim: To prospectively investigate the role of MR spectroscopy (MRS) and diffusion-weighted magnetic resonance imaging (DWI) in assessing vertebral marrow changes in postmenopausal women with osteoporosis. Materials and methods: Seventy-eight postmenopausal women (mean age 63.7 ± 3.5 years; range 55-81 years), who underwent dual-energy x-ray absorptiometry of the spine, were divided into three bone density groups (24 with normal, 25 with osteopaenic, and 29 with osteoporotic) based on T score. Both MRS and DWI of the L3 vertebral body were performed to calculate the marrow fat content and apparent diffusion coefficient (ADC). The results were compared between three groups and correlated with BMD. Results: Vertebral marrow fat content was significantly increased in the osteoporotic group (59.97 ± 5.78%), when compared with that of the osteopaenic group (53.04 ± 7.66%, p = 0.001) and the normal bone density group (48.79 ± 7.1%, p -3 mm2/s, 0.41 ± 0.02 x 10-3 mm2/s, and 0.47 ± 0.03 x 10-3 mm2/s, respectively, with statistically significant difference (P < 0.001). A statistically significant positive correlation between T scores and ADC existed (r = 0.835, p < 0.001). The vertebral marrow fat content was negatively correlated to the bone density (r = -0.639, p < 0.001) and to marrow ADC (r = -0.5 0.001) and to marrow ADC (r = -0.554, p < 0.001). Conclusion: The postmenopausal women with osteoporosis exhibited a corresponding increase in vertebral marrow fat content as the bone density decreased. Marrow fat content and ADC were related to the bone density. MRS and DWI are helpful in evaluating the bone marrow changes in postmenopausal women.

206

Assessment of global morphological and topological changes in trabecular structure under the bone resorption process  

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Osteoporosis is a frequent skeletal disease characterised both by loss of bone mineral mass and deterioration of cancellous bone micro-architecture. It can be caused by mechanical disuse, estrogen deficiency or natural age-related resorption process. Numerical analysis of high-resolution images of the trabecular network is recognised as a powerful tool for assessment of structural characteristics. Using ?CT images of 73 thoracic and 78 lumbar human vertebral specimens in vitro with isotropic resolution of 26?m we simulate bone atrophy as random resorption of bone surface voxels. Global morphological and topological characteristics provided by four Minkowski Functionals (MF) are calculated for two numerical resorption models with and without conservation of global topological connectivity of the trabecular network, which simulates different types of bone loss in osteoporosis, as it has been described in males and females. Diagnostic performance of morphological and topological characteristics as a function of relative bone loss is evaluated by a correlation analysis with respect to experimentally measured Maximum Compressive Strength (MCS). In both resorption models the second MF, which coincides with bone surface fraction BS/TV, demonstrates almost constant value of Pearson's correlation coefficient with respect to the relative bone loss ?BV/TV. This morphological characteristic does not vary considerably under age-related random resorption and can be used for predicting bone strength in the elderly. The third and fourth MF demonstrate an increasing correlation coefficients with MCS after applying random bone surface thinning without preserving topological connectivity, what can be used for improvement of evaluation of the current state of the structure.

Sidorenko, Irina N.; Bauer, Jan; Monetti, Roberto; Baum, Thomas; Rummeny, Ernst J.; Eckstein, Felix; Matsuura, Maiko; Lochmueller, Eva-Maria; Zysset, Philippe K.; Raeth, Christoph W.

2012-03-01

207

Age-related changes in rat bone-marrow mesenchymal stem cell plasticity  

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Full Text Available Abstract Background The efficacy of adult stem cells is known to be compromised as a function of age. This therefore raises questions about the effectiveness of autologous cell therapy in elderly patients. Results We demonstrated that the expression profile of stemness markers was altered in BM-MSCs derived from old rats. BM-MSCs from young rats (4 months expressed Oct-4, Sox-2 and NANOG, but we failed to detect Sox-2 and NANOG in BM-MSCs from older animals (15 months. Chondrogenic, osteogenic and adipogenic potential is compromised in old BM-MSCs. Stimulation with a cocktail mixture of bone morphogenetic protein (BMP-2, fibroblast growth factor (FGF-2 and insulin-like growth factor (IGF-1 induced cardiomyogenesis in young BM-MSCs but not old BM-MSCs. Significant differences in the expression of gap junction protein connexin-43 were observed between young and old BM-MSCs. Young and old BM-MSCs fused with neonatal ventricular cardiomyocytes in co-culture and expressed key cardiac transcription factors and structural proteins. Cells from old animals expressed significantly lower levels of VEGF, IGF, EGF, and G-CSF. Significantly higher levels of DNA double strand break marker ?-H2AX and diminished levels of telomerase activity were observed in old BM-MSCs. Conclusion The results suggest age related differences in the differentiation capacity of BM-MSCs. These changes may affect the efficacy of BM-MSCs for use in stem cell therapy.

Chase P Bryant

2011-10-01

208

Changes in Bone Mineral Density in Uterine Cervical Cancer Patients After Radiation Therapy  

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Purpose: To prospectively investigate the changes in bone mineral density (BMD) after pelvic radiation therapy in patients with uterine cervical cancer. Methods and Materials: Of 52 cervical cancer patients who received pelvic RT in our university hospital between 2009 and 2011, 46 patients without recurrence and who were followed up for more than 12 months were included in the study. The BMD of the irradiated region and nonirradiated regions, serum estradiol, tartrate-resistant acid phosphatase-5b, and N-terminal cross-linking telopeptide of collagen 1 were measured before, at 3 months after, and at 12 months after RT. The patient cohort was divided into 2 groups according to estradiol level before RT, and the groups were defined as postmenopausal (2 before RT and 0.746 and 0.841 g/cm2 12 months after RT, respectively. Significant decreases were observed in both groups (P2 before RT and were significantly decreased to 0.706 and 0.921 g/cm2 12 months after RT (P<.01 and P<.05, respectively). Estradiol significantly decreased 3 months after RT, whereas tartrate-resistant acid phosphatase-5b and N-terminal cross-linking telopeptide of collagen 1 continued to increase over time in the premenopausal group. Conclusions: A decrease in BMD in the irradiated region after RT was observed within 1 year, regardless of menopausal status. Furthermore, in premenopausal patients, pelvic RT caused a decrease in systemic BMD

209

Longitudinal changes in bone mass after one year as measured by different techniques in patients with osteoporosis.  

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Bone mass was measured in 49 postmenopausal women by the following techniques: single photon absorptiometry at the radius (SPA), dual photon absorptiometry at the lumbar spine (DPA), quantitative computed tomography at the lumbar spine with an area of interest of only trabecular bone (QCT) or of an integrated cross-section of the vertebral body (QCTi), and total body calcium by neutron activation analysis (TBCa). Each women had two measurements with a one-year interval. Half of them were treated with calcium supplementation only; the other half also received calcitriol (1,25 dihydroxycholecalciferol). The aim of this report was to compare the changes of bone mass as measured by the different techniques. The DPA and QCTi values were significantly lower at one year than at baseline (by paired t-tests). The mean percent changes (+/- SD) for the measurements were: TBC, -0.4 +/- 4.6%; SPA-1, 1.2 +/- 7.1%; SPA-2, 0.7 +/- 6.0%; DPA, -2.5 +/- 11%; QCT, 6.5 +/- 23%; and QCTi, -6.0 +/- 9%. The percent changes by one technique did not show significant correlation to the percent changes by the other methods. We conclude that the precision of the methods in this clinical setting is not sufficient to show correlations after only one year; in addition, there may have been different rates of changes at different sites of the skeleton. PMID:3093023

Ott, S M; Kilcoyne, R F; Chesnut, C H

1986-09-01

210

Investigation of reactivity changes due to flooding the irradiation sites of the MNSR reactor using the MCNP code and comparison with experimental results  

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Full Text Available In this work, the Isfahan Miniature Neutron Source Reactor (MNSR has been simulated using the MCNP code, and reactivity worth of flooding the inner irradiation sites of this reactor in an accident has been calculated. Also, by inserting polyethylene capsules containing water inside the inner irradiation sites, reactivity changes of this reactor in same such accident have been measured, the results of which are in good agreements with the calculated results. In this work, the reactivity worth due to flooding one inner irradiation site is 0.53mk , and reactivity worth due to flooding of the whole 5 inner irradiation sites is 2.61 mk.

A Shirani

2010-06-01

211

Directions of chemical change: experimental characterization of the stereodynamics of photodissociation and reactive processes.  

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This perspective article aims at accounting for the versatility of some current experimental investigations for exploring novel paths in chemical reactions. It updates a previous one [Phys. Chem. Chem. Phys., 2005, 5, 291] and is limited to work by the authors. The use of advanced molecular beam techniques together with a combination of modern tools for specific preparation, selection and detection permits us to discover new trends in reactivity in the gas phase as well as at interfaces. We specifically discuss new facets of stereodynamics, namely the effects of molecular orientation and alignment on reactive and photodissociation processes. Further topics involve roaming paths and triple fragmentation in photodissociation probed by imaging techniques, chirality effects in collisions and deviations from Arrhenius behavior in the temperature dependence of chemical reactions. PMID:24788949

Kasai, Toshio; Che, Dock-Chil; Okada, Michio; Tsai, Po-Yu; Lin, King-Chuen; Palazzetti, Federico; Aquilanti, Vincenzo

2014-06-01

212

Thymine Dimer-Induced Structural Changes to the DNA Duplex Examined with Reactive Probes†  

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Despite significant progress in the last decade, questions still remain about the complete structural, dynamic, and thermodynamic effect of the cis-syn cyclobutane pyrimidine dimer lesion (hereafter called the thymine dimer) on double-stranded genomic DNA. We examined a 19-mer oligodeoxynucleotide duplex containing a thymine dimer lesion using several small, base-selective reactive chemical probes. These molecules probe whether the presence of the dimer causes the base pairs to be more access...

Rumora, Amy E.; Kolodziejczak, Katarzyna M.; Wagner, Anne Malhowski; Nu?n?ez, Megan E.

2008-01-01

213

A study on the change of bone mineral density (BMD) by life habit and physical condition  

International Nuclear Information System (INIS)

To evaluate the correlation between BMD and life habit such as drinking exercise smoking or physical condition such as age, sex, height, weight, body mass index (BMI). I evaluated the BMD of the femoral neck and L2-L4 spines of 321 persons who took a regular health screening in Woosuk university oriental medical hospital from February to April in 2006 by dual energy bone mineral densitometry. The age of persons ranged from 20 years to 75 years (mean 45.10 ± 11.54) and there were 160 males and 161 females. In males, BMD of the femoral head was highest at 2nd decade, BMD of the spine was highest at 4th decade, and BMD of both femoral head and lumbar spine was lowest at 6th decade. In fenales, BMD of both femoral head and lumbar spine was highest at 4th decade and lowest at 6th decade. Among the various physical conditions, only height of persons showed significant correlation with BMD in both males and females, BMD was increased according to increasing height. In males, BMD of persons who had habit such as drinking, exercise or smoking did not show significant change statistically. But in females, drinking group showed high BMD relative to non-drinking group in both femoral head and lumbar spine. BMD was different according to age, sex, height and life habit. Especially aged people showed osteoporotic change progressively. More persistent effort is needed to find out the factors decreasing BMD for prevention of problems by osteoporosisporosis

214

Changes in jaw dimensions and bone density in patients with osteoporosis  

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Full Text Available Introduction Osteopenia and osteoporosis reduce the density and mass of jaw bones. Aim The aim of this study was to present the methods of radiographic analysis in patients with osteoporosis prior to restorative treatment. Method 127 panoramic radiographs (Kodak, USA and 39 retroalveolar radiographs (KD 58-R 30×40 mm, USA were used for the analysis of density (DT II 05 densitometer, England and dimensions of jaw bones with respect to segments corresponding to bone layers. Results The results of this study indicated statistically significant differences in bone density (p<0.05 and p<0.01 in patients with osteopenia. Bone density was significantly reduced (p<0.01 and p<0.001 in osteoporotic patients, when compared to controls. Significant reductions of edentulous ridges in osteoporotic patients women X=23.05 mm (kV=30.72% and X=22.85 mm (kV=28.81%, and men X=28.83 (kV=8.55% as well as X=25.36 (kV=11.43%, were observed. Conclusion Bone density of the upper and lower jaw is reduced in osteoporotic patients. At the very beginning of restorative prosthodontic therapy of osteoporotic patients, retroalveolar radiographs and panoramic radiographs should be obtained. Reference lines should be assigned, contours of the alveolar and edentulous ridges on radiographs should be analysed and bone density assessed.

Pošti? Sr?an D.

2009-01-01

215

Ovariectomy-induced changes in aged beagles : histomorphometry of rib cortical bone.  

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Bone loss associated with estrogen depletion is well documented in cancellous bone but less well characterized in cortical bone. The effects of ovariectomy on the aged beagle skeleton were studied by histomorphometric analysis of the cortical bone in sequential rib biopsies. Biopsies were taken from each ovariectomized or sham-operated dog at the time of surgery and at 1, 4, and 8.5 months after surgery. Just prior to each postoperative biopsy, tetracycline, calcein, and xylenol orange, respectively, were administered by a fluorochrome labeling procedure (2d-10d-2d) to provide markers of bone formation. Analysis of sequential rib biopsies provided a means to follow the ovariectomy response over time and to compare each animal against its own baseline. Though ovariectomy did not influence histomorphometric indices at 1 month after surgery, a transient increase in cortical bone formation occurred thereafter, with a sixfold increase over that of sham-operated dogs at 4 months (P < 0.001) and a return to near control levels at 8.5 months. Cortical porosity increased by the fourth month after ovariectomy and remained high at 8.5 months. These data demonstrate for the first time that rib cortical bone is a responsive site for the effects of ovariectomy in aged female dogs.

Wilson, A. K.; Bhattacharyya, M. H.; Miller, S.; Sacco-Gibson, N.; Center for Mechanistic Biology and Biotechnology; Univ. of Utah; Procter & Gamble Pharmaceuticals

1998-03-01

216

Ozone-induced changes in muscarinic bronchial reactivity by different testing methods.  

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We examined the effect of ozone (O3) on muscarinic bronchial reactivity in the guinea pig and compared reactivity determined by two different routes of agonist delivery. Reactivity before and from 4 h to 2 days after O3 exposure (3.0 ppm, 2 h) was determined by measuring specific airway resistance upon administration of intravenous acetylcholine and/or aerosolized methacholine challenge in 34 unanesthetized, spontaneously breathing animals. Before exposure, we observed more gradual and reproducible results to intravenous agonist. After exposure, hyperreactivity to parenteral agonist occurred consistently, but not to inhaled agonist. Hyperreactivity demonstrable by either route was similar in magnitude and time course within 14 h of exposure. Two days later, hyperreactivity to inhaled agonist had remitted; that to intravenous drug persisted. Our results indicate that variability in the occurrence and time course of O3-induced hyperreactivity to inhaled agonist may be a consequence of the technique employed. The consistent occurrence of hyperreactivity after O3 to parenteral agonist suggests mechanisms other than airway mucosal hyperpermeability are responsible for this hyperreactivity. PMID:6392228

Roum, J H; Murlas, C

1984-12-01

217

Mammographic evaluation of the changes after the breast radiotherapy for breast carcinoma. Part 2. Reactive changes in mammary tissues following radiotherapy  

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Mammographic evaluation of reactive changes after radiotherapy was carried out in 56 women with inoperable breast carcinoma treated by standard deep radiotherapy. It was found that postradiation changes in mammary tissues caused characteristic radiological signs. It was demonstrated also that the extent and intensity of these signs as well as the mode and time of their regression depend to a considerable extent on the intensity of the postradiation reaction. The diagnostic significance of the repeatedly occurring oedematous thickening of the skin in the diagnosis of local recurrence is stressed.

Moczko, W.; Luczak, I.; Ramlau, C.; Simon, E.; Moczko, J. (Akademia Medyczna, Poznan (Poland))

1981-01-01

218

The effect of purified compared with nonpurified diet on bone changes induced by hindlimb suspension of female rats  

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The purpose of this study was to compare the bone changes induced by unloading in rats fed different diets, because space flight studies use a semipurified diet, whereas space flight simulation studies typically use nonpurified diets. Female Sprague-Dawley rats were fed a purified American Institute of Nutrition (AIN) 93G diet or a standard nonpurified diet and kept ambulatory or subjected to unloading by hindlimb suspension (HLS) for 38 days. Bone mineral content (BMC), mechanical strength, and factors related to the diet that affect bone (i.e., urinary calcium excretion, estradiol, and corticosterone) were measured. Average food intakes (grams per day) differed for diets, but caloric intake (kilocalories per day) and the final body masses of treatment groups were similar. The HLS-induced decrease in femoral BMC was not statistically different for rats fed a nonpurified diet (-8.6%) compared with a purified AIN-93G diet (-11.4%). The HLS-induced decrease in femoral mechanical strength was not statistically different for rats fed a nonpurified diet (-24%) compared with a purified AIN-93G diet (-31%). However, bone lengths were decreased (P diet compared with a purified diet. Plasma estradiol levels were lower (P diet. Plasma estradiol was related to femoral BMC (r = 0.85, P diet than those fed a purified AIN-93G diet, which is consistent with the higher level of calcium in the nonpurified diet. Urinary corticosterone levels were higher (P diet than rats fed the AIN-93G diet. Although the osteopenia induced by unloading was similar in both diet groups, there were differences in longitudinal bone growth, calcium excretion, plasma estradiol levels, and urinary corticosterone levels. Results indicate that the type of standard diet used is an important factor to consider when measuring bone end points.

Tou, Janet C L.; Arnaud, Sara B.; Grindeland, Richard; Wade, Charles

2005-01-01

219

The effect of purified compared with nonpurified diet on bone changes induced by hindlimb suspension of female rats  

Science.gov (United States)

The purpose of this study was to compare the bone changes induced by unloading in rats fed different diets, because space flight studies use a semipurified diet, whereas space flight simulation studies typically use nonpurified diets. Female Sprague-Dawley rats were fed a purified American Institute of Nutrition (AIN) 93G diet or a standard nonpurified diet and kept ambulatory or subjected to unloading by hindlimb suspension (HLS) for 38 days. Bone mineral content (BMC), mechanical strength, and factors related to the diet that affect bone (i.e., urinary calcium excretion, estradiol, and corticosterone) were measured. Average food intakes (grams per day) differed for diets, but caloric intake (kilocalories per day) and the final body masses of treatment groups were similar. The HLS-induced decrease in femoral BMC was not statistically different for rats fed a nonpurified diet (-8.6%) compared with a purified AIN-93G diet (-11.4%). The HLS-induced decrease in femoral mechanical strength was not statistically different for rats fed a nonpurified diet (-24%) compared with a purified AIN-93G diet (-31%). However, bone lengths were decreased (P rats fed a nonpurified diet compared with a purified diet. Plasma estradiol levels were lower (P rats fed a nonpurified diet. Plasma estradiol was related to femoral BMC (r = 0.85, P rats fed a nonpurified diet than those fed a purified AIN-93G diet, which is consistent with the higher level of calcium in the nonpurified diet. Urinary corticosterone levels were higher (P rats fed a nonpurified diet than rats fed the AIN-93G diet. Although the osteopenia induced by unloading was similar in both diet groups, there were differences in longitudinal bone growth, calcium excretion, plasma estradiol levels, and urinary corticosterone levels. Results indicate that the type of standard diet used is an important factor to consider when measuring bone end points.

Tou, Janet C L.; Arnaud, Sara B.; Grindeland, Richard; Wade, Charles

2005-01-01

220

Late-onset persistent retinal microvascular changes after bone marrow transplantation: 3-year follow-up  

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Full Text Available Purpose: To describe a case of persistent retinopathy after bone marrow transplantation in the absence of radiation therapy. Methods: Case Report. Results: A 42 year-old man developed bilateral visual loss 15 months after receiving a bone marrow transplant for acute leukemia. The patient was treated with a high dose of cyclosporin A and oral corticosteroids. No radiation therapy was given. Late-onset, multiple, bilateral cotton-wool spots developed 15 months after the bone marrow transplantation and still persist. After three years other cotton-wool spots arose in the absence of any immunosuppressive therapy. Conclusions: Bone marrow transplantation microvasculopathy of the retina may be related to certain combinations of chemotherapy drugs or immunosuppression itself and may persist in the absence of these immunosuppressive drugs.

Muccioli Cristina

2002-01-01

 
 
 
 
221

Stress Distribution at the Bone-Cement Interface Changes During Kyphoplasty Rehabilitation  

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Balloon Kyphoplasty uses an inflatable bone tamp and cement augmentation to repair vertebral compression fractures. A recent clinical study observed a 78% re-collapse rate in patients showing a radiolucent phenomenon at the bone-cement interface following Kyphoplasty. Two experimental studies showed significant height loss following Balloon Kyphoplasty under cyclical loads. The present study investigates the alteration in load angle corresponding to this height loss and its effect on load tra...

Purcell, Philip; Tiernan, Stephen; Mcevoy, Fiona; Tyndyk, Magdalena; Morris, Seamus

2013-01-01

222

Microarray analysis of changes in bone cell gene expression early after cadmium gavage in mice  

International Nuclear Information System (INIS)

We developed an in vivo model for cadmium-induced bone loss in which mice excrete bone mineral in feces beginning 8 h after cadmium gavage. Female mice of three strains [CF1, MTN (metallothionein-wild-type), and MT1,2KO (MT1,2-deficient)] were placed on a low-calcium diet for 2 weeks. Each mouse was gavaged with 200 ?g Cd or vehicle only. Fecal calcium was monitored daily for 9 days, beginning 4 days before cadmium gavage, to document the bone response. For CF1 mice, bones were taken from four groups: +/- Cd, 2 h after Cd and +/- Cd, 4 h after Cd. MTN and MT1,2KO strains had two groups each: +/-Cd, 4 h after Cd. PolyA+ RNA preparations from marrow-free shafts of femura and tibiae of each +/- Cd pair were submitted to Incyte Genomics for microarray analysis. Fecal Ca results showed that bone calcium excreted after cadmium differed for the three mouse strains: CF1, 0.24 ± 0.08 mg; MTN, 0.92 ± 0.22 mg; and MT1,2KO, 1.7 ± 0.4 mg. Gene array results showed that nearly all arrayed genes were unaffected by cadmium. However, MT1 and MT2 had Cd+/Cd- expression ratios >1 in all four groups, while all ratios for MT3 were essentially 1, showing specificity. Both probes for MAPK 14 (p38 MAPK) had expression ratios >1, while no other MAPK responded to cadmium. Vacuolar proton pump ATPase and integrin alpha v (osteoclast genes), transferrin receptor, and src-like adaptor protein genes were stimulated by Cd; other src-related genes were unaffected. Genes for bone formation, stresected. Genes for bone formation, stress response, growth factors, and signaling molecules showed little or no response to cadmium. Results support the hypothesis that Cd stimulates bone demineralization via a p38 MAPK pathway involving osteoclast activation

223

Effect of strontium ranelate on bone mineral: Analysis of nanoscale compositional changes.  

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Strontium ranelate has been used to prevent bone loss and stimulate bone regeneration. Although strontium may integrate into the bone crystal lattice, the chemical and structural modifications of the bone when strontium interacts with the mineral phase are not completely understood. The objective of this study was to evaluate apatite from the mandibles of rats treated with strontium ranelate in the drinking water and compare its characteristics with those from untreated rats and synthetic apatites with and without strontium. Electron energy loss near edge structures from phosphorus, carbon, calcium and strontium were obtained by electron energy loss spectroscopy in a transmission electron microscope. The strontium signal was detected in the biological and synthetic samples containing strontium. The relative quantification of carbon by analyzing the CK edge at an energy loss of ?E = 284 eV showed an increase in the number of carbonate groups in the bone mineral of treated rats. A synthetic strontium-containing sample used as control did not exhibit a carbon signal. This study showed physicochemical modifications in the bone mineral at the nanoscale caused by the systemic administration of strontium ranelate. PMID:24207060

Rossi, André L; Moldovan, Simona; Querido, William; Rossi, Alexandre; Werckmann, Jacques; Ersen, Ovidiu; Farina, Marcos

2014-01-01

224

Changes in hemopoiesis of dying and surviving mice after fractionated irradiation and repeated bone marrow transplantation  

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Mice received doses of 3 Gy of {sup 60}Co-gamma rays total body irradiation at four-day intervals up to a total dose of 24 Gy. After each dose per fraction half of the animals were injected with 10{sup 6} bone marrow cells. At four- and nine-day intervals evaluations were made of the blood count, bone marrow and spleen cellularities, and spleen mass. In animals subjected only to irradiation the damage of hemopoietic organs was becoming deeper until the end of observation; the majority of these mice died by nine days after the irradiation with the last dose per fraction (by 37 days of the experiment). The authors consider anemia as the main cause of their death. All of the mice that were given bone marrow injections survived; nine days after the last dose of irradiation the mean cellularities of their bone marrows and spleens were 76.8% and 112.3% of the unirradiated controls respectively. In general, regeneration of erythropoiesis was quite successful, the number of thrombocytes was positively influenced, and the number of leukocytes nearly unchanged in bone marrow recipients when compared with the only irradiated mice. We observed two periods of maximum and one of minimum bone marrow and spleen regeneration, which were not synchronized. These results deny an unrepairable damage to the hemopoietic microenvironment in conditions of our experiment. This paper follows up with our preceding work describing results of an experiment which ended on day 24. (orig.).

Tkadlecek, L.; Viklicka, S.; Hofer, M.; Karpfel, Z. (Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav (Germany, F.R.))

1990-02-01

225

Changes in hemopoiesis of dying and surviving mice after fractionated irradiation and repeated bone marrow transplantation  

International Nuclear Information System (INIS)

Mice received doses of 3 Gy of 60Co-gamma rays total body irradiation at four-day intervals up to a total dose of 24 Gy. After each dose per fraction half of the animals were injected with 106 bone marrow cells. At four- and nine-day intervals evaluations were made of the blood count, bone marrow and spleen cellularities, and spleen mass. In animals subjected only to irradiation the damage of hemopoietic organs was becoming deeper until the end of observation; the majority of these mice died by nine days after the irradiation with the last dose per fraction (by 37 days of the experiment). The authors consider anemia as the main cause of their death. All of the mice that were given bone marrow injections survived; nine days after the last dose of irradiation the mean cellularities of their bone marrows and spleens were 76.8% and 112.3% of the unirradiated controls respectively. In general, regeneration of erythropoiesis was quite successful, the number of thrombocytes was positively influenced, and the number of leukocytes nearly unchanged in bone marrow recipients when compared with the only irradiated mice. We observed two periods of maximum and one of minimum bone marrow and spleen regeneration, which were not synchronized. These results deny an unrepairable damage to the hemopoietic microenvironment in conditions of our experiment. This paper follows up with our preceding work describing results of an experiment which ended on day 24. (orig.)

226

Molecular changes in articular cartilage and subchondral bone in the rat anterior cruciate ligament transection and meniscectomized models of osteoarthritis  

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Full Text Available Abstract Background Osteoarthritis (OA is a debilitating, progressive joint disease. Methods Similar to the disease progression in humans, sequential events of early cartilage degradation, subchondral osteopenia followed by sclerosis, and late osteophyte formation were demonstrated in the anterior cruciate ligament transection (ACLT or ACLT with partial medial meniscectomy (ACLT + MMx rat OA models. We describe a reliable and consistent method to examine the time dependent changes in the gene expression profiles in articular cartilage and subchondral bone. Results Local regulation of matrix degradation markers was demonstrated by a significant increase in mRNA levels of aggrecanase-1 and MMP-13 as early as the first week post-surgery, and expression remained elevated throughout the 10 week study. Immunohistochemistry confirmed MMP-13 expression in differentiated chondrocytes and synovial fibroblasts at week-2 and cells within osteophytes at week-10 in the surgically-modified-joints. Concomitant increases in chondrocyte differentiation markers, Col IIA and Sox 9, and vascular invasion markers, VEGF and CD31, peaked around week-2 to -4, and returned to Sham levels at later time points in both models. Indeed, VEGF-positive cells were found in the deep articular chondrocytes adjacent to subchondral bone. Osteoclastic bone resorption markers, cathepsin K and TRAP, were also elevated at week-2. Confirming bone resorption is an early local event in OA progression, cathepsin K positive osteoclasts were found invading the articular cartilage from the subchondral region at week 2. This was followed by late disease events, including subchondral sclerosis and osteophyte formation, as demonstrated by the upregulation of the osteoanabolic markers runx2 and osterix, toward week-4 to 6 post-surgery. Conclusions In summary, this study demonstrated the temporal and cohesive gene expression changes in articular cartilage and subchondral bone using known markers of OA progression. The findings here support genome-wide profiling efforts to elucidate the sequential and complex regulation of the disease.

Zhuo Ya

2011-08-01

227

The changes of CD34+ cells in C57 mouse bone marrow after irradiation and their roles in dysfunction of hematopoiesis  

International Nuclear Information System (INIS)

Objective: To observe the changes of CD34+ cells in C57 mouse bone marrow after irradiation and investigate the role of apoptosis in radiation-induced dysfunction of hematopoiesis. Methods: Flow cytometric enumeration of CD34+ hematopoietic stem and progenitor cells by double fluorescent labelling apoptosis detection by Annexin V-FITC kit, and cell cycle detection by PI labelling were carried out. Results: 1) compared with the normal group, the percentage of CD34+ cells in bone marrow nucleated cells decreased at least for 14 days after irradiation, and the changes were related with irradiation doses, 2) At 6 h after irradiation, the largest amount of apoptosis cells could be detected. 3) Bone marrow cell cycle was perturbed after 5.5 Gy irradiation. Conclusion: The percentage of CD34+ hematopoietic stem and progenitor cells in C57 mouse bone marrow decreased after irradiation, and apoptosis might be responsible for the changes of the bone marrow cells

228

Patterns of magnetic resonance imaging bone erosion in rheumatoid arthritis--which bones are most frequently involved and show the most change?  

DEFF Research Database (Denmark)

To investigate by magnetic resonance imaging (MRI) which bones in wrists and metacarpophalangeal (MCP) joints most frequently show bone erosions, and which most frequently demonstrate erosive progression, in early and established rheumatoid arthritis (RA).

Østergaard, Mikkel; MØller DØhn, Uffe

2011-01-01

229

Patterns of magnetic resonance imaging bone erosion in rheumatoid arthritis - which bones are most frequently involved and show the most change?  

DEFF Research Database (Denmark)

To investigate by magnetic resonance imaging (MRI) which bones in wrists and metacarpophalangeal (MCP) joints most frequently show bone erosions, and which most frequently demonstrate erosive progression, in early and established rheumatoid arthritis (RA).

HØrslev-Petersen, Kim; Junker, Peter

2011-01-01

230

Changes in composition and deposition rates in the reactive sputtering of copper, titanium, and yttrium exposed to oxygen  

International Nuclear Information System (INIS)

Copper, titanium, and yttrium oxide films were prepared by reactive dc magnetron sputtering in an Ar-O2 plasma and the deposition rates and compositional changes were measured as a function of dc power. The deposition rates of Cu increased monotonically with increasing dc power, while those of Ti and Y increased abruptly by more than one order of magnitude at a critical dc power (P/sub c/). Abrupt compositional changes of metal and oxygen in the thin films were also observed for Ti and Y at P/sub c/. The compositional change curve for Cu had a plateau in dc power dependence. These results correlate with the differences of heat of oxide formation among Cu, Ti, and Y

231

Simulation of chemically reactive solute transport under conditions of changing temperature  

International Nuclear Information System (INIS)

A numerical code, THCC, has been developed for simulation of multicomponent solute transport in saturated porous media with aqueous complexation and precipitation/dissolution of stable solid phases in the presence of variable temperature. THCC evolved from the isothermal code CHEMTRN and is capable of simulating the diffusion of solutes along a steady gradient of temperature and the mixing of fluids having different initial compositions and temperatures. Example calculations demonstrate the close coupling that can exist between temperature variations and the transport of chemically reactive solutes. This coupling can be an important consideration in the assessment of performance of nuclear waste repositories

232

Bone mineral density changes of the proximal tibia after revision total knee arthroplasty. A randomised study with the use of porous tantalum metaphyseal cones  

DEFF Research Database (Denmark)

Forty patients were enrolled in a prospective randomised study using conventional method or "Trabecular Metal Cone" (TM Cone) (Zimmer inc., Warsaw, USA) for reconstruction of bone loss of the proximal tibia during revision total knee arthroplasty (rTKA). The aim was to evaluate changes in bone mineral density (BMD) at the proximal tibia.

Jensen, Claus L; Petersen, Michael M

2012-01-01

233

Changes in Bone Mineral Density in Uterine Cervical Cancer Patients After Radiation Therapy  

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Purpose: To prospectively investigate the changes in bone mineral density (BMD) after pelvic radiation therapy in patients with uterine cervical cancer. Methods and Materials: Of 52 cervical cancer patients who received pelvic RT in our university hospital between 2009 and 2011, 46 patients without recurrence and who were followed up for more than 12 months were included in the study. The BMD of the irradiated region and nonirradiated regions, serum estradiol, tartrate-resistant acid phosphatase-5b, and N-terminal cross-linking telopeptide of collagen 1 were measured before, at 3 months after, and at 12 months after RT. The patient cohort was divided into 2 groups according to estradiol level before RT, and the groups were defined as postmenopausal (<40 pg/mL) and premenopausal (?40 pg/mL). Results: The mean BMDs within the irradiation field (lumbar vertebra 5) in the postmenopausal and the premenopausal groups were 0.825 and 0.910 g/cm{sup 2} before RT and 0.746 and 0.841 g/cm{sup 2} 12 months after RT, respectively. Significant decreases were observed in both groups (P<.05 and P<.01, respectively). In addition, in the premenopausal group the mean BMDs of the nonirradiated regions at thoracic vertebrae 9-12 and lumbar vertebrae 2-4 were 0.753 and 0.958 g/cm{sup 2} before RT and were significantly decreased to 0.706 and 0.921 g/cm{sup 2} 12 months after RT (P<.01 and P<.05, respectively). Estradiol significantly decreased 3 months after RT, whereas tartrate-resistant acid phosphatase-5b and N-terminal cross-linking telopeptide of collagen 1 continued to increase over time in the premenopausal group. Conclusions: A decrease in BMD in the irradiated region after RT was observed within 1 year, regardless of menopausal status. Furthermore, in premenopausal patients, pelvic RT caused a decrease in systemic BMD.

Okonogi, Noriyuki; Saitoh, Jun-ichi; Suzuki, Yoshiyuki, E-mail: syoshi@gunma-u.ac.jp; Noda, Shin-ei; Ohno, Tatsuya; Oike, Takahiro; Ohkubo, Yu; Ando, Ken; Sato, Hiro; Nakano, Takashi

2013-12-01

234

Effects of ethnicity and vitamin D supplementation on vitamin D status and changes in bone mineral content in infants  

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Full Text Available Abstract Background To evaluate the effects on serum 25(OHD and bone mineralization of supplementation of breast-fed Hispanic and non-Hispanic Caucasian infants with vitamin D in infants in Houston, Texas. Methods We measured cord serum 25(OHD levels, bone mineral content (BMC, bone mineral density (BMD and their changes over 3 months of life with 400 IU/day of vitamin D3 supplementation. Results Cord serum 25(OHD was significantly lower in Hispanic than non-Hispanic Caucasian infants (16.4 ± 6.5 ng/mL, n = 27, vs 22.3 ± 9.4 n = 22, p = 0.013. Among 38 infants who completed a 3 month vitamin D supplementation intervention, provision of 400 IU/day of vitamin D increased final 25(OHD to a higher level in non-Hispanic Caucasian compared to Hispanic infants. There was no significant relationship between cord serum 25(OHD and BMC or BMD in the first week of life (n = 49 or after 3 months of vitamin D supplementation. Conclusion Low cord 25(OHD levels are seen in Hispanic infants, but their functional significance is uncertain related to bone health in a southern US setting. Daily vitamin D intake of 400 IU during the first months of life appears adequate to increase serum 25(OHD and support BMC increases despite low initial 25(OHD levels in some infants. Trial Registration ClincalTrials.gov NCT00697294

Abrams Steven A

2012-01-01

235

Improving the textural characterization of trabecular bone structure to quantify its changes: the locally adapted scaling vector method  

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We extend the recently introduced scaling vector method (SVM) to improve the textural characterization of oriented trabecular bone structures in the context of osteoporosis. Using the concept of scaling vectors one obtains non-linear structural information from data sets, which can account for global anisotropies. In this work we present a method which allows us to determine the local directionalities in images by using scaling vectors. Thus it becomes possible to better account for local anisotropies and to implement this knowledge in the calculation of the scaling properties of the image. By applying this adaptive technique, a refined quantification of the image structure is possible: we test and evaluate our new method using realistic two-dimensional simulations of bone structures, which model the effect of osteoblasts and osteoclasts on the local change of relative bone density. The partial differential equations involved in the model are solved numerically using cellular automata (CA). Different realizations with slightly varying control parameters are considered. Our results show that even small changes in the trabecular structures, which are induced by variation of a control parameters of the system, become discernible by applying the locally adapted scaling vector method. The results are superior to those obtained by isotropic and/or bulk measures. These findings may be especially important for monitoring the treatment of patients, where the early recognition of (drug-induced) changes in the trabecular structure is crucial.

Raeth, Christoph W.; Mueller, Dirk; Boehm, Holger F.; Rummeny, Ernst J.; Link, Thomas M.; Monetti, Roberto

2005-04-01

236

The role of estrogen in bone growth and formation: changes at puberty  

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Full Text Available Divya Singh1, Sabyasachi Sanyal2, Naibedya Chattopadhyay11Division of Endocrinology, 2Division of Drug Target Discovery and Development, Central Drug Research Institute (Council of Scientific and Industrial Research, Lucknow, Uttar Pradesh, IndiaAbstract: A high peak bone mass (PBM at skeletal maturity is a good predictor for lower rate of fracture risks in later life. Growth during puberty contributes significantly to PBM achievement in women and men. The growth hormone (GH/insulin-like growth factor 1 (IGF-1 axis has a critical role in pubertal bone growth. There is an increase in GH and IGF-1 levels during puberty; thus, it is assumed that sex steroids contribute to higher GH/IGF-1 action during growth. Recent studies indicate that estrogen increases GH secretion in boys and girls, and the major effect of testosterone on GH secretion is via aromatization to estrogen. Estrogen is pivotal for epiphyseal fusion in young men and women. From studies of individuals with a mutated aromatase gene and a case study of male patient with defective estrogen receptor-alpha (ER-?, it is clear that estrogen is indispensable for normal pubertal growth and growth plate fusion. ER-? and estrogen receptor-beta (ER-? have been localized in growth plate and bone. ER knockout studies have shown that ER-?-/- female mice have reduced linear appendicular growth, while ER-?-/- mice have increased appendicular growth. No such effect is seen in ER-?-/- males; however, repressed growth is seen in ER-?-/- males, resulting in shorter long bones. Thus, ER-? represses longitudinal bone growth in female mice, while it has no function in the regulation of longitudinal bone growth in male mice. These findings indicate that estrogen plays a critical role in skeletal physiology of males as well as females.Keywords: peak bone mass, puberty, estrogen, growth plate

Divya Singh

2010-12-01

237

CHANGES INDUCED BY SOME NUTRITIONAL FACTORS ON TIBIAL BONE STRUCTURE IN PIG  

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Full Text Available The problems approached by our team are represented by the involvement of different sources and levels of calcium, namely calcium carbonate, fructoborate and alfalfa, in the mineralization of bone tissue. So, we made fix histological preparations of tissue fragments taken from tibia bone, from 9 pigs belonging to three batches: the control batch, where calcium was provided in a proportion of 1% through calcium carbonate, experimental batch 1, where calcium was provided in a proportion of 1.04% through fructoborate, on a calcium carbonate support, and experimental batch 2, where calcium was provided in a proportion of 1.13% through fructoborate + alfalfa, on a calcium carbonate support. The histomorphometric parameters assessed were represented by the volume of bone trabeculae (BV/TV, % or the percentage of bone tissue in a given volume and the mean width of bone trabeculae. At the same time, in order to establish fructoborate and alfalfa implication in bone mineralization, we supervised the presence and activity of osteoblasts respectively osteoclasts. In the case of the experimental batch 1, the histomorphometric study shows an increase of bone trabeculae dimension, with a mean width of about 142,5? ?, and also an increase of their mean volume, which is about 37,11%. The trabecular system is dense and present mineralised and ossified territory where are formed by osteoclasts with osteocytes. Peritrabeculary are presented active osteoblasts which are involved in plurilamellar stratification by deposition of young collagen. In the case of individuals from experimental batch 2, trabeculae mean width is about 140,7?, while their volume is 35,62%.

GABI DUMITRESCU

2013-07-01

238

Changes in bone mineral density and bone metabolism markers in premenopausal women with multiple sclerosis and the relationship to clinical variables.  

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Bone mineral density (BMD) is affected in young adults with multiple sclerosis (MS), which leads to disabling disease. We aimed to show changes that were independent of immobilization by measuring BMD and laboratory markers of bone metabolism in mobile MS patients. We compared a total of 52 premenopausal female patients with relapsing-remitting multiple sclerosis (RRMS) to 41 women of similar age who had no risk factors for osteoporosis. The lumbar and femur BMD were measured using the dual energy X-ray absorptiometry (DXA) method. The urine concentration of serum 25-hydroxycholecalciferol (25-OH vit D(3)), and pyridinoline and deoxypyridinoline were also measured. The concentration of serum osteocalcin was measured to determine the speed of bone metabolism. The mean age of patients (+/- standard deviation [SD]) was 36.1+/-7.4. The average Expanded Disability Status Scale (EDSS) score was 2.2+/-1.8. The concentration of 25-OH vit D(3) and osteocalcin was lower, whereas the concentration of parathyroid hormone (PTH), alkaline phosphatase (ALP), pyridinoline and deoxypyridinoline was higher in the patient group. In the patient group, lumbar 2-4 BMD, T score and Z score and femur neck and trochantor BMD, T score and Z score were significantly lower than in the control group. There was a significant negative relationship between: the disease period and L 2-4 BMD, T score and Z scores; and the femoral neck BMD, T score and Z scores. There was a significant relationship between the total Functional Independence Measure score and the femoral neck, femoral trochanter BMD, T score, and Z score. There was a significant negative relationship between the average EDSS, L 2-4 and all the DXA measurements obtained from the femur. There was a significant relationship between the 25-OH vit D(3) concentration and L 2-4 T score and Z score from the DXA measurements obtained from the femur. There were no significant relationships between osteocalcin, pyridinoline, deoxypyridinoline levels and the BMD measurements. Therefore, the duration of the disease and decrease in functional capacity are the main factors that affect BMD in MS. Apart from the decrease in functional capacity, 25-OH vit D(3) deficiency and secondary PTH increase contribute to the BDM changes observed in MS. PMID:20619660

Terzi, Tülay; Terzi, Murat; Tander, Berna; Cantürk, Ferhan; Onar, Musa

2010-10-01

239

[Comparison of reactive EEG changes and fMRI characteristics of brain health based on multivariate statistics].  

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To gain a deeper insight into the relationship between the electrogenesis and oxygenation of the brain, fMRI and EEG reactions to identical functional loads (opening of the eyes and right- and left-hand fingering) were compared in 11 young right-handed healthy subjects with statistical techniques. Changes in power, frequency and coherent EEG parameters obtained by 18-channel monopolar recording were compared with values of + BOLD-fMRI response, calculated for 18 corresponding cortical areas on the basis of application of the "virtual cap" by the original algorithm. In reactive changes of both hemodynamic and bioelectrical parameters, sets of independent factors were identified, which were regarded on the basis of their topography as specific (localized in the cortical representation ofa relevant analyzer) and nonspecific (diffuse and similar under different functional loads). Specific component dominated in the fMRI response, whereas non-specific component was characteristic of the EEG reaction. The similar topography of reactive fMRI and EEG factors under normal conditions, confirmed by the correlation analysis, reflects the multilevel character of the systemic organization of the brain activity, visualized, in particular, in the sagittal projections of the individual fMRI images. Each of the reactive EEG factors included all of the EEG quantitative characteristics. EEG coherence, which dominated among other parameters (with a local increase in the cortical representation of a relevant analyzer and a diffuse decrease in the areas of the influence of the regulatory structures) displayed the highest correlation with hemodynamic responses of the brain. PMID:22690544

Sharova, E V; Migalev, A S; Kulikov, M A; Voronov, V G; Boldyreva, G N; Zhavoronkova, L A; Skoriatina, I G; Piashina, D V; Davydova, N Iu; Pronin, I N; Kornienko, V N

2012-01-01

240

Localized sclerotic bone response demonstrated reduced nanomechanical creep properties.  

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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 ?) 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 (?) were also observed, our results indicate that sclerotic response of bone metastasis would cause reduced toughness (increased ?) with stiffening of material (increased E and H). PMID:23127639

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

2013-01-01

 
 
 
 
241

Reactive nitrogen in the environment and its effect on climate change  

International Nuclear Information System (INIS)

Humans have doubled levels of reactive nitrogen in circulation, largely as a result of fertilizer application and fossil fuel burning. This massive alteration of the nitrogen cycle affects climate, food security, energy security, human health and ecosystem services. Our estimates show that nitrogen currently leads to a net-cooling effect on climate with very high uncertainty. The many complex warming and cooling interactions between nitrogen and climate need to be better assessed, taking also into account the other effects of nitrogen on human health, environment and ecosystem services. Through improved nitrogen management substantial reductions in atmospheric greenhouse gas concentrations could be generated, also allowing for other co-benefits, including improving human health and improved provision of ecosystem services, for example clean air and water, and biodiversity.

242

Three-month change in the radiodensity of alveolar bone supporting partial-denture abutment teeth.  

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This study uses the intraoral microdensitometric method to examine the impact of masticatory pressure on the alveolar bone around the abutment teeth clasp. Two retroalveolar radiographs were carried out on all 30 subjects over a period of 3 months using a copper calibration stepwedge. The dental radiographs were digitized and converted into positive. Grey level values on dental radiographs in the alveolar bone area in 7 region of interest (ROI) were measured. They were converted into the equivalent thickness of the calibration stepwedge using mathematical methods and the difference of the bone density between the two radiographs was calculated. The results demonstrated that there were no statistically significant differences between the 1st and 2nd radiographs in any of ROI (p > 0.05). PMID:12674851

Kovacevi?, D; Deli?, Z; Celebi?, A; Kovac, Z; Grzi?, R; Uhac, I; Zlatari?, D Knezovic

2002-12-01

243

Changes of density distribution of the subchondral bone plate after supramalleolar osteotomy for valgus ankle osteoarthritis.  

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CT-osteoabsorptiometry (CT-OAM) has been used to visualize subchondral bone plate density distribution regarding to its mineralization. The purpose of this study was to display and analyze the density distribution of the subchondral bone plate before and after supramalleolar realignment osteotomies. We retrospectively analysed pre- and postoperative CT images of nine consecutive patients with post-traumatic unilateral valgus ankle OA. The distribution charts of CT-OAM scans were quantitatively analyzed for subchondral bone plate density distribution. VAS for pain and the Tegner activity scale were used to assess clinical outcome. At a mean follow-up of 20?±?5.6 months (range 13-27), we observed a significant pre- to postoperative decrease of the mean high-density area ratio in tibia (lateral and posterior area) (p???0.05) and the talus (lateral area) (p???0.05). Pairwise comparison between the pre- and postoperative mineralization at the articular surface showed a significant decrease of the high-density area ratio for the tibia and the talus. The VAS decreased from 6.2?±?0.9 pre- to 2.8?±?0.9 postoperatively (p?=?0.027), and the Tegner score inclined from 4.5?±?1.1 preoperatively to 5.3?±?0.7 after surgery (p?=?0.082). The tibial and talar subchondral bone plate density, regarding to its mineralization, decreased after supramalleolar medial closing wedge osteotomy in patients with valgus ankle OA. The results of this study suggest that realignment surgery may decrease peak bone density areas corresponding to the alignment correction and contribute to a homogenization of the subchondral bone plate mineralization. PMID:25042395

Egloff, Christian; Paul, Jochen; Pagenstert, Geert; Vavken, Patrick; Hintermann, Beat; Valderrabano, Victor; Müller-Gerbl, Magdalena

2014-10-01

244

Evaluation of airway dimensions and changes in hyoid bone position following class II functional therapy with activator.  

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Abstract Aim. The aim of this study was to evaluate the long-term effects of Class 2 functional treatment on airway dimensions and positional changes in hyoid bone and compare it with that of an untreated Class 2 control group. Methods. Lateral cephalograms of 16 patients (eight girls, eight boys, mean chronological age = 11.36 ± 0.77 years) who were treated with activator and 19 patients (11 girls, eight boys, mean chronological age = 12.14 ± 0.65 years) who served as control were used for linear, angular and area measurements regarding airway track and hyoid bone. Statistics. Intra-group comparisons were performed by paired t-test and Wilcoxon test, whereas independent t-test and Mann Whitney-U were used for inter-group comparisons. Results. During treatment (T2-T1), nasopharyngeal height and nasopharyngeal area increased (p T3-T2); nasopharyngeal (p < 0.01) and oropharyngeal area increased (p < 0.05). H-SN (p < 0.01) and C3-H distances (p < 0.05) increased. Hyoid bone position exhibited significant changes (H-SN, p < 0.001; C3-H, p < 0.01). The increases in C3-H in long-term was more in the activator group than control (p < 0.05). Conclusions. In growing Class 2 patients with mandibular deficiency and airway track without obstructions, functional appliance treatment provided favorable effects on nasopharyngeal and oropharyngeal area throughout the retention period. PMID:24909154

Ulusoy, Cagri; Canigur Bavbek, Nehir; Tuncer, Burcu Balos; Tuncer, Cumhur; Turkoz, Cagri; Gencturk, Zeynep

2014-11-01

245

[WHO classification of tumours of soft tissue and bone 2013: the main changes compared to the 3rd edition].  

Science.gov (United States)

In early 2013, the new classification of tumours of soft tissue and bones was released. This edition belongs to the fourth series of so-called Blue Books published under the auspices of the World Health Organisation (WHO). The current classification follows the previous third edition, from which it differs in several aspects. The vast majority of changes are related to the soft tissue tumour section, which was enriched with three new chapters, some entities or terms were removed, new diagnoses were introduced, and several tumours were reallocated to other categories. Albeit to a lesser extent, similar changes have occurred also in the classification of bone tumours. Compared to the previous edition, more detailed molecular and cytogenetic data were incorporated in the current issue. The rapidly increasing knowledge of the genetics of mesenchymal tumours allows us to make more accurate diagnoses as well as to better understand of the pathogenesis of these lesions. However, abundant molecular and cytogenetic data highlight an increasing problem of growing numbers of genetic overlaps even among quite different tumours. The coexistence of several grading systems of soft tissue tumours is another controversial issue mentioned in the recent WHO classification. The main advantages and limitations of the two most widely used grading systems are also discussed. Keywords: WHO classification - sarcoma - soft tissues - bones - tumour. PMID:24758500

Zambo, Iva; Veselý, Karel

2014-04-01

246

The composition of the mesenchymal stromal cell compartment in human bone marrow changes during development and aging.  

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Life-long hematopoiesis depends on the support of mesenchymal stromal cells within the bone marrow. Therefore, changes in the hematopoietic compartment that occur during development and aging probably correlate with variation in the composition of the stromal cell microenvironment. Mesenchymal stromal cells are a heterogeneous cell population and various subtypes may have different functions. In accordance with others, we show that CD271 and CD146 define distinct colony-forming-unit-fibroblast containing mesenchymal stromal cell subpopulations. In addition, analysis of 86 bone marrow samples revealed that the distribution of CD271(bright)CD146(-) and CD271(bright)CD146(+) subsets correlates with donor age. The main subset in adults was CD271(bright)CD146(-), whereas the CD271(bright)CD146(+) population was dominant in pediatric and fetal bone marrow. A third subpopulation of CD271(-)CD146(+) cells contained colony-forming-unit-fibroblasts in fetal samples only. These changes in composition of the mesenchymal stromal cell compartment during development and aging suggest a dynamic system, in which these subpopulations may have different functions. PMID:21993672

Maijenburg, Marijke W; Kleijer, Marion; Vermeul, Kim; Mul, Erik P J; van Alphen, Floris P J; van der Schoot, C Ellen; Voermans, Carlijn

2012-02-01

247

The Effect of Global Change on Surface Ozone and Reactive Nitrogen Concentrations: Implications for the Biosphere  

Science.gov (United States)

We simulated two ten year periods using the global chemical transport model MOZART-2 (Model of Ozone and Related chemical Tracers version 2): 1990-2000 and 2090-2100. In each case MOZART-2 is driven by meteorology from the National Center for Atmospheric Research (NCAR) coupled Climate Systems Model (CSM) 1.0 forced with the (SRES) A1 scenario. Profound future changes in the summertime climate over the U.S. are found including changes in temperature, water vapor and clouds and the frequency of synoptic venting of the boundary layer. Even allowing for no changes in emissions in the future, the changes in climate alone drive a significant increase in the ozone concentration over the eastern U.S. (up to 5 ppbv on average) and an increase in the persistence of pollution events. Implications of these changes on the biosphere are assessed with and without allowing for the impact of climate on biogenic emissions. Furthermore the changes in climate alone cause large changes in the partitioning of NOy, decreasing PAN by over 20% over the U.S. Coupled with changes in precipitation; this induces significant changes in the deposition of nitrogen species to the biosphere in a future climate.

Hess, P. G.; Murazaki, K.; Emmons, L.; Lamarque, J.

2005-12-01

248

Characterization of dynamic changes in vascular reactivity following treatment with carmustine in Sprague-Dawley rats  

International Nuclear Information System (INIS)

Carmustine, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), is a highly effective anti-cancer drug and bone marrow suppressant agent in humans and animals. Pilot studies demonstrated that BCNU induced a time- and dose-dependent supersensitivity to norepinephrine (NE) in rat caudal arteries after a single dose. The studies presented in this thesis were performed to determine the mechanism for this supersensitivity. Male Sprague-Dawley rats were administered a single dose of BCNU (25 mg/kg, i.p.) on day 0. On day 7 a proximal section of caudal artery was doubly cannulated and perfused intraluminally with Krebs bicarbonate physiological buffer. These studies demonstrated that the supersensitivity induced by BCNU treatment was pre-junctional. Denervation of caudal arteries with 6-hydroxydopamine led to a significant decrease in the EC50 for NE in caudal arteries from control rats but not BCNU treated rats. The EC50 for NE in control-denervated arterial segments was not statistically different from BCNU-denervated or BCNU-nondenervated segments. Metabolism of [3H] NE to its 5 primary metabolites, as determined by thin layer chromatography, and uptake of [3H] NE were significantly lower in caudal arteries taken from BCNU treated rats. These data demonstrate that a pre-junctional mechanism was responsible for vascular supersensitivity to NE after BCNU treatment in caudal arteries from Sprague-Dawley rats

249

Location change method for imaging chemical reactivity and catalysis with single-molecule and -particle fluorescence microscopy.  

Science.gov (United States)

In the last eight years, it has become possible to image chemical reactivity at the single-molecule and -particle level with fluorescence microscopy. This Perspective describes one of the imaging techniques that enabled this state-of-the-art application: imaging by the location change of molecules and particles. In this method, the microscope and experiment are configured to produce a signal when an individual molecule or particle changes location or changes mobility concurrently with a chemical change. This imaging technique has enabled observation of single chemical reactions and unraveled mechanisms of complex chemical and physical processes in transition metal and polymerization systems. This Perspective has three major goals: (1) to unify studies of different chemical processes or of different chemical questions, which, in spite of these differences, employ a similar microscopy detection method, (2) to explain the technique to nonexperts and those who might be interested in joining this nascent field, and (3) to highlight unique information available through this cross-disciplinary technique and the value this information has for chemical reaction development generally and catalysis specifically. To this end, application of the location change method to the investigation of polymerization reactions with radical initiators and separately with metal catalysts, and to ligand exchange reactions at platinum complexes are described. PMID:24695617

Blum, S A

2014-08-21

250

RADIOGRAPHIC EVALUATION OF OSTEOPOROSIS THROUGH DETECTION OF JAW BONE CHANGES: A SIMPLIFIED EARLY OSTEOPOROSIS DETECTION EFFORT  

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Full Text Available Osteoporosis has become a worldwide problem and has been known as a silence disease. Nowadays, there are a lot of diagnostic tools for detecting osteoporosis. Eighty eight postmenopausal were included and underwent digital panoramic, digital periapical, and conventional radiography. Ultrasound bone densitometry of os calcis used as gold standard. Correlation between stiffness index (SI with a digital dental, digital panoramic and conventional dental radiography are 0.170 (p = 0.11, -0382 (p = 0.001 and 0.246 (p = 0.021 respectively. Significant relationship was found between the SI only with digital panoramic and conventional dental. The highest correlation was found between SI values with mandibular Inferior Cortex on digital panoramic (-0.382, Pearson Correlation Tests. Correlation between digital panoramic radiographs and the SI values was the highest of the three radiographic modalities in this study. This indicates that evaluation of cortical bone is more accurate than cancellous bone. Bone quality evaluation in patients at high risk for osteoporosis using panoramic and dental conventional radiograph by dentist, contributes in preventing further occurrence of osteoporosis which in turn could reduce mortality and morbidity of osteoporosis in Indonesia.

Menik Priminiarti

2010-12-01

251

[The role of scintigraphy in the diagnosis of mandibular bone changes].  

Science.gov (United States)

Investigating the scintigraphic images of jaws may have a diagnostic value of bone alterations of dental origin. Anterior view of whole body bone scintigraphy revealed hot spot on jaws of 61% (279) of patients. Twenty-six patients (mean age 58.3 year) from all of those who had increased tracer uptake (ITU) in the maxillo-mandibular region were called back for dental examination. 279 out of 459 (61%) patients had ITU in the maxillo-mandibular region. Dental examination revealed the dental origin of ITU in all cases. In case of periapical pathosis tracer uptake showed 28.79% increase compared to the contralateral side. In marginal periodontitis 23.82% ITU was found. In case of loading due to prosthesis 13.06% ITU was observed. The mean DMF-T value was 26.36 +/- 4.52 (D = 4.12, M = 20.8, F = 1.44). The prosthetic index was 0.42 on the mandible. The above mentioned data mean very low oral health conditions of the patients included in this examination. The results show that bone scintigraphy is a valuable procedure in detecting tooth related jaw lesions. Bone scintigraphy provides very useful data on oral health of these patients. Enrolling of these patients into regular dental care is inevitable. PMID:14971261

Dobó, Nagy Csaba; Korányi, Mariann; Keszthelyi, Gusztáv; Fejérdy, Pál; Ackermann, Gábor; Galuska, László

2003-12-01

252

Changes of the proliferation kinetics of human bone marrow in vivo through hydroxyurea  

International Nuclear Information System (INIS)

A 10-hour oral continuous infusion with hydroxyurea (HU) at a non-toxic concentration was performed in 20 malignoma patients with undisturbed bone marrow. Bone marrow taken before, during and after HU-administration was examined for 3H-TdR incorporation by means of autoradiography and liquid scintimetry, for cell phase distribution by means of flow cytophotometry, morphologically and by means of CFUc. 3H-TdR incorporation into bone marrow cells dropped to 16% of the initial value under HU and rose to 156% 10 h after HU-effect terminated. Cytophotometry did not furnish any proof of a decrease of S-phase cells or increase of cells in G1-to-S-transition during HU. S-cells rise to 129% of the initial value 10 h after having fallen below minimum inhibition concentration. Under HU, there is an equal number of cells in S which incorporate much less 3H-thymidine; after HU more S-cells incorporate more 3H-thymidine than before HU. During HU action, DNA synthesis activity is reduced to 17% and reaches the initial value with 105% afterwards. In human bone marrow, hydroxyurea in non-toxic concentration causes a temporary DNA synthesis inhibition in terms of activity reduction and partial arrest in S. A stop-and-go of the cell cycle effected by HU does not occur; the effect is rather a slow-down of DNA synthesis. (orig./MG)

253

Inhibition of leukotriene function can modulate particulate-induced changes in bone cell differentiation and activity.  

Science.gov (United States)

Aseptic loosening remains the major problem facing arthroplasty longevity with particulates from component materials touted as the cause of periprosthetic osteolysis. Proposed mechanisms in aseptic bone loss include: increased resorption, increased differentiation of osteoclasts (and/or macrophages locally), and decreased osteoblastic bone formation. Leukotrienes participate in osteoclastic bone resorption. We investigated inhibiting leukotrienes synthesis, using ICI 230487, to ameliorate the effects of particulates on osteoclast pit formation and also assessed the effects of alendronate, a bisphosphonate, on pit formation. Three particulates were used: ultra high molecular weight polyethylene (UHMWPE), polymethylmethacrylate (PMMA) and hydroxyapatite (HA). Osteoclast resorption was increased with UHMWPE, PMMA, and HA particles. Interventions with alendronate and ICI 230487 reduced particulate-induced osteoclast resorption. Both ICI 230487 and alendronate reduced osteoclast numbers at higher doses. To assess the effect of particulates on osteoclast and macrophage differentiation, mouse bone marrow was cultured and stained for tartrate resistant acid phosphatase colonies (TRAP+, osteoclasts) and nonspecific esterase positive colonies (NSE+, macrophage precursors). Particulates increased both TRAP+ and NSE+ colony formation. These increases were inhibited by ICI 230487. Particulates also inhibited osteoblast function assessed by the development of mineralized nodules and alkaline phosphatase positive (AP+) colony area. ICI 230487 partly protected osteoblast function from this particulate effect. Blockade of leukotriene production may prove a useful therapeutic intervention for particulate-induced aseptic loosening by inhibiting resorptive activity, reducing the pro-inflammatory cell populations induced and recruited by these particulates, as well as ameliorating the negative effects of inflammatory mediators on osteoblast function. PMID:11410899

Anderson, G I; MacQuarrie, R; Osinga, C; Chen, Y F; Langman, M; Gilbert, R

2001-01-01

254

Will Global Climate Change Alter Fundamental Human Immune Reactivity: Implications for Child Health?  

Directory of Open Access Journals (Sweden)

Full Text Available The human immune system is an interface across which many climate change sensitive exposures can affect health outcomes. Gaining an understanding of the range of potential effects that climate change could have on immune function will be of considerable importance, particularly for child health, but has, as yet, received minimal research attention. We postulate several mechanisms whereby climate change sensitive exposures and conditions will subtly impair aspects of the human immune response, thereby altering the distribution of vulnerability within populations—particularly for children—to infection and disease. Key climate change-sensitive pathways include under-nutrition, psychological stress and exposure to ambient ultraviolet radiation, with effects on susceptibility to infection, allergy and autoimmune diseases. Other climate change sensitive exposures may also be important and interact, either additively or synergistically, to alter health risks. Conducting directed research in this area is imperative as the potential public health implications of climate change-induced weakening of the immune system at both individual and population levels are profound. This is particularly relevant for the already vulnerable children of the developing world, who will bear a disproportionate burden of future adverse environmental and geopolitical consequences of climate change.

Ashwin Swaminathan

2014-11-01

255

Reactivation in post-traumatic chronic osteomyelitis: ultrasonographic findings  

International Nuclear Information System (INIS)

To describe the ultrasound (US) features of reactivation in post-traumatic chronic osteomyelitis in adults. Twelve patients with clinical suspicion of reactivation of chronic osteomyelitis, secondary to trauma, surgery, and who were investigated with US were selected for the study. The following US features were assessed: periosseous fluid collection, bone changes (periosteal reactions, cortical irregularity, callus, sequestrum and cloaca) and soft-tissue changes (cellulitis and sinus tracts). US findings were correlated with plain radiography (n = 11), computed tomography (n = 3) and magnetic resonance imaging (n = 2). US detected fluid collections in all patients (12 periosseous and 3 in soft tissues), bone changes in 10 and sinus tracts and cellulitis in 5 patients each. Bone changes detected were cortical irregularity (n = 10), discontinuity of cortex (n = 7), sequestrum (n = 2), callus (n = 2), periosteal reaction (n = 1) and cloaca (n = 1). Cellulitis was seen in 5 patients and sinus tracts in 5. Reactivation was confirmed at surgery in all patients. US is a reliable noninvasive imaging modality for the diagnosis of reactivation of post-traumatic chronic osteomyelitis in adults. (author)

256

Bone X-Ray (Radiography)  

Medline Plus

Full Text Available ... injury, infection, arthritis , abnormal bone growths and bony changes seen in metabolic conditions. assist in the detection and diagnosis of bone cancer . locate foreign objects ...

257

MRI of the cuboid bone: Analysis of changes in diabetic versus non-diabetic patients and their clinical significance  

International Nuclear Information System (INIS)

Objectives: (1) To investigate the association between diabetes and marrow changes in the cuboid; and (2) to evaluate the influence of age, gender, body mass index (BMI) and use of insulin in the occurrence of marrow changes in the cuboid. Research design and methods: MR and X-ray foot examinations of 237 patients [94 males, 143 females; mean age, 47.1 years (range 16–93 years)], five of whom underwent bilateral examinations, were reviewed. MR and radiographic studies were analyzed for the presence of marrow edema and fractures in the cuboid. Findings were correlated with demographic data (age, gender) and clinical information (BMI and use of insulin). Results: Two hundred and forty two feet – 69 diabetic and 173 non-diabetic – were retrospectively evaluated. There was a higher prevalence of marrow edema and fractures in the diabetic cuboid (n = 31, 45%) compared to non-diabetic cuboid (n = 25, 14%, p = 0.02). A fracture line was seen in fourteen (20%) diabetic cuboid bones compared to 4 (2%) in non-diabetic cuboid bones (p < 0.0001). Eleven (79%) cases of cuboid fractures in the diabetic population were radiographically occult. Multivariate data analysis revealed an adjusted odds ratio of 4.416 (95% CI; 2.307, 8.454) for the relationship between marrow changes (edema and fractures) in the cuboid and diabetes. For each year of age, the odds of changes in the cuboid increased by 2.2% (95% CI; 1.001, 1.044). Conclusion: Despite not bearing weight, the cuboid bone is more vulnerable to marrow edema and fractures in diabetic patients compared to non-diabetic patients. Age seems to be an influential factor

258

Pain flare following external beam radiotherapy and meaningful change in pain scores in the treatment of bone metastases  

International Nuclear Information System (INIS)

Background and purpose: To examine the incidence of pain flare following external beam radiotherapy and to determine what constitutes a meaningful change in pain scores in the treatment of bone metastases. Patients and methods: Patients with bone metastases treated with external beam radiotherapy were asked to score their pain on a scale of 0-10 before the treatment (baseline), daily during the treatment and for 10 days after completion of external beam radiation. Pain flare was defined as a two-point increase from baseline pain in the pain scale of 0-10 with no decrease in analgesic intake or a 25% increase in analgesic intake employing daily oral morphine equivalent with no decrease in pain score. To distinguish pain flare from progression of pain, we required the pain score and analgesic intake to return back to baseline levels after the increase/flare. They were also asked to indicate if their pain changed during that time compared to pre-treatment level. The change in pain score was compared with patient perception. Results: Eighty-eight patients were evaluated in this study. There were 49 male and 39 female patients with the median age of 70 years. Twelve of 88 patients (14%) had pain flare on day 1. The overall incidence of pain flare during the study period ranged from 2 to 16%. A total of 797 pain scorings were obtained. Patients perceived an improvement in pain when their self-reported pain score decreased by at least two points. Conclusions: Our study confirms the occurrence of pain flare following the external beam radiotherapy in the treatment of bone metastases. Further studies are required to predict who are at risk for flare. Appropriate measures can be taken to alleviate the pain flare. The finding in the meaningful change in pain scores supports the investigator-defined partial response used in some clinical trials

259

Detection of radiation-induced changes in electrochemical properties of austenitic stainless steels using miniaturized specimens and the single-loop electrochemical potentiokinetic reactivation method  

International Nuclear Information System (INIS)

Single-loop electrochemical potentiokinetic reactivation testing of miniaturized (TEM) specimens can provide reliable data comparable to data obtained with larger specimens. Significant changes in electrochemical properties (increased reactivation current and Flade potential) were detected for PCA and type 316 stainless steels irradiated at 200--420 degrees C up to 7--9 dpa. Irradiations in the FFTF Materials Open Test Assembly and in the Oak Ridge Research Reactor are reported on. 45 figs., 5 tabs., 52 refs

260

TCDD decreases ATP levels and increases reactive oxygen production through changes in mitochondrial F F1-ATP synthase and ubiquinone  

International Nuclear Information System (INIS)

Mitochondria generate ATP and participate in signal transduction and cellular pathology and/or cell death. TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) decreases hepatic ATP levels and generates mitochondrial oxidative DNA damage, which is exacerbated by increasing mitochondrial glutathione redox state and by inner membrane hyperpolarization. This study identifies mitochondrial targets of TCDD that initiate and sustain reactive oxygen production and decreased ATP levels. One week after treating mice with TCDD, liver ubiquinone (Q) levels were significantly decreased, while rates of succinoxidase and Q-cytochrome c oxidoreductase activities were increased. However, the expected increase in Q reduction state following TCDD treatment did not occur; instead, Q was more oxidized. These results could be explained by an ATP synthase defect, a premise supported by the unusual finding that TCDD lowers ATP/O ratios without concomitant changes in respiratory control ratios. Such results suggest either a futile cycle in ATP synthesis, or hydrolysis of newly synthesized ATP prior to release. The TCDD-mediated decrease in Q, concomitant with an increase in respiration, increases complex 3 redox cycling. This acts in concert with glutathione to increase membrane potential and reactive oxygen production. The proposed defect in ATP synthase explains both the greater respiratory rates and the lower tissue ATP levels

 
 
 
 
261

Framework for reactive mass transport : Phase change modeling of concrete by a coupled mass transport and chemical equilibrium model  

DEFF Research Database (Denmark)

Reactive transport modeling is applicable for a range of porous materials. Here the modeling framework is focused on cement-based materials, where ion diffusion and migration are described by the Poisson-Nernst-Planck equation system. A two phase vapor/liquid flow model, with a sorption hysteresis description is coupled to the system. The mass transport is solved by using the finite element method where the chemical equilibrium is solved explicitly by an operator splitting method. The IPHREEQC library is used as chemical equilibrium solver. The equation system, solved by IPHREEQC, is explained for aqueous, pure phase and solid solution reactions. Numerical examples, with cement-based materials, are constructed to demonstrate transient phase change modeling. A simulation of pure multi-species leaching from the material, showing deterioration of the solid phases is described and calculated. A second simulation, showing multi-species ingress with formation of new solid phases in the domain is described and calculated. It is shown that the numerical solution method is capable of solving the reactive mass transport system for the examples considered. (C) 2014 Elsevier B.V. All rights reserved.

Jensen, Mads MØnster; Johannesson, Björn

2014-01-01

262

Diabetes and change in bone mineral density at the hip, calcaneus, spine, and radius in older women  

Directory of Open Access Journals (Sweden)

Full Text Available Older women with type 2 diabetes mellitus (DM have higher bone mineral density (BMD but also have higher rates of fracture compared to those without DM. Limited evidence suggests that DM may also be associated with more rapid bone loss. To determine if bone loss rates differ by DM status in older women, we analyzed BMD data in the Study of Osteoporotic Fractures (SOF between 1986 and 1998. SOF participants were women >65 years at baseline who were recruited from four regions in the U.S. DM was ascertained by self-report. BMD was measured with dual x-ray absorptiometry (DXA at baseline and at least one follow-up visit at the hip (N=6624 and calcaneus (N=6700 and, on a subset of women, at the spine (N=396 and distal radius (N=306. Annualized percent change in BMD was compared by DM status, using random effects models. Of 6,867 women with at least one follow-up DXA scan, 409 had DM at baseline. Mean age was 70.8 (SD 4.7 years. Baseline BMD was higher in women with DM at all measured sites. In models adjusted for age and clinic, women with prevalent DM lost bone more rapidly than those without DM at the femoral neck (-0.96% vs. -0.59% per year, p < 0.001, total hip (-0.98% vs. -0.70% per year, p<0.001, calcaneus (-1.64% vs. -1.40% per year, p=0.005, and spine (-0.33% vs. +0.33% per year, p=0.033, but not at the distal radius (-0.97% vs. -0.90% per year, p=0.91. These findings suggest that despite higher baseline BMD, older women with DM experience more rapid bone loss than those without DM at the hip, spine and calcaneus, but not the radius. Higher rates of bone loss may partially explain higher fracture rates in older women with DM.

AnnV.Schwartz

2013-05-01

263

Age-related changes in bone mineral density, cross-sectional area and the strength of long bones in the hind limbs and first lumbar vertebra in female wistar rats  

International Nuclear Information System (INIS)

Age-related changes in bone mineral density (BMD) and cross-sectional area and bone strength index (SSI) of the femur, tibia, humerus. and first lumbar vertebra in female Wistar (WM/MsNrs) rats were examined by a quantitative computed tomography (pQCT) method. One hundred and sixteen virgin female Wistar (WM/MsNrs) rats aged 2-33 months were used. The data indicate that the total BMD values of metaphyses and diaphyses of long bones increased until 12 months, then decreased to a varying degree depending on the bone after 15-24 months, but the values of cortical and trabecular BMD with age were not always similar to the total BMD value. Nevertheless, the values for cross-sectional area and SSI in the long bones increased regardless of the total BMD decrease with age, indicating that this increase might have been due to a characteristic of the modeling pattern in rats. The total and cortical BMD values in the first lumbar vertebra decreased after 18 months, and SSI did after 15 months. The data obtained in this study were compared with those obtained from males in a previous study. In conclusion, it was indicated that in this strain the rats over 12 months with the highest total BMD values in the femur and tibia, and before the onset of various tumors, are useful as a model animal for osteoporosis experiments and observation of senile bone change

264

Changes of bone mineral density and related parameters in patients of hyperthyroidism before and after 131I therapy  

International Nuclear Information System (INIS)

Objective: To investigate the changes of bone metabolism in patients with hyperthyroidism before and after 131I therapy. Methods: The serum levels of TT3, TT4, sensitive thyroid-stimulating hormone (sTSH), bone gla protein (BGP), parathyroid hormone (PTH) and calcitonin (CT) of 58 patients with hyperthyroidism were measured and also the serum alkaline phosphatase (ALP), calcium (Ca) and phosphorus (P) levels. The bone mineral density (BMD) of the forearm, lumbar (L2-L4) and femur was obtained by dual photon X-ray before and after 131I therapy. Results: 1) Both BMD between the patients treated after 6 months, and before treatment, also the BMD between various 131I treated group and no response group had significant differences (P3 level before therapy was positively correlative to the serum BGP (r=0.4113, t=2.9896, P3 and CT/PTH radio (r=0.3613, t=2.6836, P131I therapy (authors)

265

Comparison of radiographic subchondral bone changes with arthroscopic findings in the equine femoropatellar and femorotibial joints: a retrospective study of 72 joints (50 horses)  

International Nuclear Information System (INIS)

Radiographs of 72 femoropatellar and femorotibial joints from 50 horses were evaluated. Ninety four arthroscopically evaluated areas were graded according to a predetermined system. The radiographic grade was then compared to arthroscopic findings in the same location. Statistical analysis was performed to determine the association between the radiographic subchondral bone changes and arthroscopic findings. Radiographically normal areas in the femoropatellar joint were arthroscopically positive for cartilaginous changes in 40% of the femoropatellar joints. Areas of mild subchondral bone flattening (grade I) in the lateral trochlear ridge were arthroscopically positive for cartilage changes 78% of the time. Ninety six percent of moderate to severe subchondral bone changes (grades II-V) were arthroscopically positive for cartilage damage. This research demonstrates that (1) a significant number of radiographically normal joints will have cartilage changes, (2) areas of mild subchondral bone flattening have cartilage changes present in the majority of cases and (3) areas of moderate to severe subchondral bone changes have arthroscopically detectable cartilage changes present

266

Bone tumor  

Science.gov (United States)

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 ...

267

Studies in skeletal tracer kinetics. V: Computer-simulated Tc-99m (Sn)MDP bone-scan changes in some systemic disorders: concise communication  

International Nuclear Information System (INIS)

Using compartmental analysis techniques, we modeled the biodistribution of Tc-99m(Sn)methylene diphosphonate in humans on a computer, and by selectively perturbing appropriate rate constants, we simulated changes in contrast between bone and soft tissue in a number of systemic disorders. The model predicts low contrast in patients with moderate to marked edema, obesity, congestive heart failure or decreased cardiac output states and high contrast with as little as 25% increase in bone avidity for the tracer. In acute renal failure without fluid-volume imbalance, image contrast should be normal. The model predicts greater contrast shortly after injection in patients with increased cardiac output, skeletal blood flow, or bone avidity; images made at these times would be indistinguishable. These simulations are in keeping with reports in the literature of bone images and bone-to-soft tissue ratios in many of these conditions, suggesting that modeling studies could play an important role image interpretation

268

Bone marrow cytomorphological changes in patients co-infected with visceral leishmaniasis and human immunodeficiency virus  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Visceral leishmaniasis (VL) is a severe systemic infectious disease.(1) It has been recognized as an opportunistic disease in patients infected with human immunodeficiency virus (HIV).(2,3) The analysis of the bone marrow of patients co-infected with VL and HIV showed dysplasia of erythroid, granulo [...] cytic and megakaryocytic lineages (Figure 1), besides the presence of plasmacytosis, cytoplasmic bodies, hemophagocytosis, granuloma and intracellular and extracellular leishmania amastigotes (Figure 2). These findings are found in the analysis of bone marrow of patients co-infected with HIV and VL; knowledge of these findings may be useful for the diagnosis and prognosis of patients.

Alana Jocelina Montenegro de, Castro; Romelia Pinheiro, Gonçalves; Maria Helena da Silva, Pitombeira.

269

Early changes in 25-hydroxyvitamin D levelsand bone markers after monthly risedronatewith cholecalciferol in Korean patients with osteoporosis  

Directory of Open Access Journals (Sweden)

Full Text Available Ho Yeon Chung,1 Jawon Koo,1 Su Kyoung Kwon,2 Moo-IL Kang,3 Seong-Hwan Moon,4 Jin-Young Park,5 Chan Soo Shin,6 Byung-Koo Yoon,7 Hyun-Koo Yoon,8 Jae-Suk Chang,9 Yoon-Sok Chung,10 Hyoung-Moo Park111Department of Internal Medicine, Kyung Hee University, 2Department of Statistics, 3Department of Internal Medicine, Catholic University of Korea, 4Department of Orthopedics, Yonsei University, 5Department of Orthopedics, Konkuk University, 6Department of Internal Medicine, Seoul National University, 7Department of Obstetrics and Gynecology, Sungkyunkwan University, 8Department of Internal Medicine, Kwandong University, 9Department of Orthopedics, University of Ulsan, Seoul, South Korea; 10Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, South Korea; 11Department of Obstetrics and Gynecology, Chung-Ang University, Seoul, South KoreaPurpose: This study investigated the efficacy and safety of monthly risedronate, with and without cholecalciferol, on 25-hydroxyvitamin D (25[OH]D levels and bone markers in Korean patients with osteoporosis.Methods: A randomized, double-blinded, prospective, 16-week clinical trial was conducted in ten hospitals. A total of 150 subjects with osteoporosis were randomized to one of the two treatment groups: RSDM+ (monthly risedronate 150 mg and cholecalciferol 30,000 IU combined in a single pill, n = 74 or RSDM (monthly risedronate 150 mg alone, n = 76. We measured serum levels of 25-hydroxyvitamin D (25[OH]D, parathyroid hormone (PTH, and bone markers, as well as performing muscle-function tests at baseline and after 16 weeks of treatment.Results: After 16 weeks, serum 25(OHD levels significantly increased from 17.8 to 26.8 ng/mL in the RSDM+ group, but did not change in the RSDM group. The RSDM+ group exhibited significantly decreased serum PTH from 46 to 36.7 pg/mL, while the RSDM group showed a tendency for PTH to increase from 38 to 40.6 pg/mL. In both groups, serum bone-specific alkaline phosphatase and C-terminal telopeptide rapidly declined, with significance at 16 weeks; there were no significant differences between the groups.Conclusion: A once-monthly pill of risedronate and cholecalciferol provided equivalent antiresorptive efficacy to risedronate alone in terms of bone turnover and improved 25(OHD levels over the 16-week treatment period without significant adverse events in Korean patients with osteoporosis. Keywords: bisphosphonate, cholecalciferol, bone markers, 25(OHD

Chung HY

2013-05-01

270

Platelet reactivity changes significantly throughout all trimesters of pregnancy compared with the nonpregnant state: a prospective study.  

LENUS (Irish Health Repository)

Platelets play an important role in the pathophysiology of uteroplacental disease and platelet reactivity may be an important marker of uteroplacental disease activity. However, platelet reactivity has not been evaluated comprehensively in normal pregnancy. We sought to evaluate platelet reactivity using a number of agonists at defined time points in pregnancy using a novel platelet assay and compare these with a nonpregnant cohort.

Burke, N

2013-12-01

271

Study on proliferative responses to host Ia antigens in allogeneic bone marrow chimera in mice: sequential analysis of the reactivity and characterization of the cells involved in the responses  

International Nuclear Information System (INIS)

Irradiation bone marrow chimeras were established by reconstitution of lethally irradiated AKR mice with C57BL/10 marrow cells to permit serial analysis of the developing reactivities of lymphocytes from such chimeras, [B10----AKR], against donor, host, or third party antigens. We found that substantial proliferative responses to Ia antigens of the recipient strain and also to third party antigens were generated by the thymocytes obtained from the irradiation chimeras at an early stage after bone marrow reconstitution. The majority of the responding thymocytes had surfaces lacking demonstrable peanut agglutinin receptors and were donor type Thy-1+, Ly-2-, and L3T4+ in both anti-recipient and anti-third party MLR. In anti-host responses, however, Ly-2+ thymocytes seemed to be at least partially involved. This capacity of thymus cells to mount a response to antigens of the recipient strain declined shortly thereafter, whereas the capacity to mount MLR against third party antigens persisted. The spleen cells of [B10----AKR] chimeras at the same time developed a more durable capability to exhibit anti-host reactivities and a permanent capability of reacting to third party allo-antigens. The stimulator antigens were Ia molecules on the stimulator cells in both anti-recipient and anti-third party MLR. The responding splenocytes were of donor origin and most of them had Thy-1+, Ly-1+2-, and L3T4+ phenotype

272

Age-related molecular genetic changes of murine bone marrow mesenchymal stem cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Mesenchymal stem cells (MSC) are pluripotent cells, present in the bone marrow and other tissues that can differentiate into cells of all germ layers and may be involved in tissue maintenance and repair in adult organisms. Because of their plasticity and accessibility these cells are also prime candidates for regenerative medicine. The contribution of stem cell aging to organismal aging is under debate and one theory is that reparative processes deteriorat...

Yu Hong

2010-01-01

273

Urinary Acid Excretion Can Predict Changes in Bone Metabolism During Space Flight  

Science.gov (United States)

Mitigating space flight-induced bone loss is critical for space exploration, and a dietary countermeasure would be ideal. We present here preliminary data from a study where we examined the role of dietary intake patterns as one factor that can influence bone mineral loss in astronauts during space flight. Crewmembers (n=5) were asked to consume a prescribed diet with either a low (0.3-0.6) or high (1.0-1.3) ratio of animal protein to potassium (APro:K) before and during space flight for 4-d periods. Diets were controlled for energy, total protein, calcium, and sodium. 24-h urine samples were collected on the last day of each of the 4-d controlled diet sessions. 24-h urinary acid excretion, which was predicted by dietary potential renal acid load, was correlated with urinary n-telopeptide (NTX, Pearson R = 0.99 and 0.80 for the high and low APro:K sessions, respectively, pdiet and bone interrelationships during space flight as well as on Earth. The study was funded by the NASA Human Research Program.

Zwart, Sara R.; Smith, Scott M.

2011-01-01

274

Investigate methods for measuring muscle and bone mass changes in astronauts and animals which occur during space flight  

Science.gov (United States)

Sodium-22 is being used as a tracer for bone mineral metabolism studies. Dogs are being grown from puppies to adulthood on a diet containing a constant level of sodium-22 in order to uniformly tag the entire skeleton with a long lived radionuclide. This study is still in progress and the dogs are still growing. Potassium-40 measurements were made on people, who are replacing muscle mass lost due to leg injuries, in a second study. It appears that potassium-40 measurements provide an accurate and convenient method for determining relative changes in the muscle content of the leg.

Palmer, H. E.

1977-01-01

275

Reactive Kripke semantics  

CERN Document Server

This text offers an extension to the traditional Kripke semantics for non-classical logics by adding the notion of reactivity. Reactive Kripke models change their accessibility relation as we progress in the evaluation process of formulas in the model. This feature makes the reactive Kripke semantics strictly stronger and more applicable than the traditional one. Here we investigate the properties and axiomatisations of this new and most effective semantics, and we offer a wide landscape of applications of the idea of reactivity. Applied topics include reactive automata, reactive grammars, rea

Gabbay, Dov M

2013-01-01

276

Changes in functional activity of bone tissue cells under space flight conditions.  

Science.gov (United States)

The space flight conditions affect considerably the state of bone tissue, leading to the development of osteoporosis and osteopenia. Many aspects of reactions of bone tissue cells still remain unclear until now. With the use of electron microscopy we studied the samples gathered from the femoral bon?s metaphyses of rats flown on board the space laboratory (Spacelab - 2) during 2 weeks and samples from tibial bones of mice C57 Black ( Bion ?-1). It was established, that under microgravity conditions there occur remodelling processes in a spongy bone related with a deficit of support load. In this work the main attention is focused on studying the ultrastructure of osteogenetic cells and osteoclasts. The degree of differentiation and functional state are evaluated according to the degree of development of organelles for specific biosynthesis: rough endoplasmic reticulum (RER), Golgy complex (GC), as well as the state of mitochondria and cell nucleus. As compared with a synchronous control, the population of osteogenetic cells from zones of bone reconstruction shows a decrease in the number of functionally active forms. We can judge of this from the reduction of a specific volume of RER, GC, mitochondria in osteoblasts. RER loses architectonics typical for osteoblasts and, as against the control, is represented by short narrow canaliculi distributed throughout the cytoplasm; some canals disintegrate. GC is slightly pronounced, mitochondria become smaller in size and acquire an optically dark matrix. These phenomena are supposed to be associated with the desorganization of microtubules and microfilaments in the cells under microgravity conditions. The population of osteogenetic cells shows a decrease in the number of differentiating osteoblasts and an increase in the number of little-differentiated stromal cells. In the population of osteoblasts, degrading and apoptotic cells are sometimes encountered. Such zones show a numerical increase of monocytic cells and osteoclasts. Among them are typical osteoclasts with 3 to 4 nuclei on a section, as well as the "giant" cells with 5 to 6 nuclei and a highly developed zone 2, in which organelles and structures are concentrated, providing for specific functions (primary and secondary lysosomes, heterophagous vacuoles, fibrous layer and "brush border"). The availability of these functionally active osteoclasts testify to the intensification of resorptive processes in remodelling zones. To confirm the obtained electronmicroscopic findings, the experiments were conducted on albino rats under model microgravity conditions ("tail suspension" method) with the use of radionuclides. The experiments with 3H-glycine demonstrated a lower isotope uptake in the osteogenetic cells compared with the control. The autoradiographic studies employing 3H-thymidine, showed that hind limbs unloading leads to a significant acceleration of osteoclast formation in zones of spongy bone reconstruction. Considering the obtained results, the cell mechanisms of osteoclast - osteoblast remodelling and bone tissue loss under the action of space flight factors are discussed.

Rodionova, Natalia; Nesterenko, Olga; Kabitskaya, Olga

277

Arsenic induces mitochondria-dependent apoptosis by reactive oxygen species generation rather than glutathione depletion in Chang human hepatocytes  

Energy Technology Data Exchange (ETDEWEB)

This study was conducted to evaluate the possible involvement of mitochondrial pathway in NaAsO{sub 2}-induced apoptosis and the role of reactive oxygen species (ROS) and reduced glutathione (GSH) in the apoptotic effect in Chang human hepatocytes. The MTT assay demonstrated that sodium arsenite (NaAsO{sub 2}) treatment for 24 h caused a dose-dependent decrease of cell viability. NaAsO{sub 2} treatment (0-30{mu}M) was also found to induce phosphatidylserine externalization, a hallmark of apoptosis; to disrupt the mitochondrial membrane potential ({delta}{psi}{sub m}); to cause the release of cytochrome c into the cytosol, and to trigger cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP) in a dose-dependent manner. All these changes were accompanied with the enhanced generation of intracellular ROS and malondialdehyde (MDA). Increase of intracellular GSH also coincided unexpectedly. Moreover, the extracellular addition of N-acetyl-l-cysteine (NAC, 5 mM) effectively reduced the generation of ROS and MDA, and rescued the cells from NaAsO{sub 2} induced apoptosis and related alteration of mitochondria. These data suggest that the arsenic-induced cell apoptosis occurs though the mitochondrial pathway, and is mostly dependent on generation of ROS rather than GSH depletion in Chang human hepatocytes. (orig.)

Wang, Yi; Xu, Yuanyuan; Wang, Huihui; Xue, Peng; Li, Xin; Li, Bing; Zheng, Quanmei; Sun, Guifan [China Medical University, Department of Occupational and Environmental Health, College of Public Health, Shenyang (China)

2009-10-15

278

3D Modelling and monitoring of denervated muscle under Functional Electrical Stimulation treatment and associated bone structural changes  

Directory of Open Access Journals (Sweden)

Full Text Available A novel clinical rehabilitation method for patients who have permanent and non recoverable muscle denervation in the legs was developed in the frame of the European Project RISE. The technique is based on FES and the project results shows, in these severely disabled patients, restoration of muscle tissue and function. This study propose novel methods based on image processing technique and medical modelling to monitor growth in denervated muscle treated with FES. Geometrical and structural changes in muscle and bone are studied and modelled. Secondary effects on the bone mineral density produced by the stimulation treatment and due the elicited muscle contraction are also investigated. The restoration process in DDM is an important object of discussion since there isn’t yet a complete understanding of the mechanisms regulating growth in denervated muscle. This study approaches the problem from a macroscopic point of view, developing 3-dimensional models of the whole stimulated muscles and following changes in volume, geometry and density very accurately. The method is based on the acquisition of high resolution Spiral CT scans from patients who have long-term flaccid paraplegia and the use of special image processing tools allowing tissue discriminations and muscle segmentation. Three patients were measured at different points of time during 4 years of electrical stimulation treatment. In this study is quantitatively demonstrated the influences of FES treatment on the different quadriceps bellies. The rectus femoris muscle is positioned in the middle of the quadriceps and responds (in general better to stimulation. In a patient with abundant adipose tissue surrounding the quadriceps, rectus femoris almost doubled the volume during the FES treatment while in the other bellies the changes measured were minimal. The analysis of the density shows clearly a restoration of the muscular structure in the growing muscle. The remarkable increase of muscle mass and the improved quality of the muscle tissue was observed and measured on whole muscle volume. The 3-dimensional approach proposed in this work allows the geometrical changes in denervated muscle to be measured. Central lines in rectus femoris are calculated during the treatment and the relative curvature indexes are used to quantify differences between data sets. The result shows a correlation between degeneration status and changes in shape; the differences in curvature between control and denervated muscle diminish with the growth. Furthermore, bone mineral density is measured on the femur to monitor the structural changes induced by the current flow and to evaluate the effect on the patella bone density due to the quadriceps contraction. Though the evidences aren’t yet statistically relevant a kind of structural change in the femur is measured as secondary effect from the muscle stimulation. Beside, the force applied on the patella through the elicited contraction seems also to have a beneficial effect on bone density. Indeed the mineral loss in the patella is remarkably slowed down.

Paolo Gargiulo

2011-03-01

279

Heavy-metal-induced reactive oxygen species: phytotoxicity and physicochemical changes in plants.  

Science.gov (United States)

As a result of the industrial revolution, anthropogenic activities have enhanced there distribution of many toxic heavy metals from the earth's crust to different environmental compartments. Environmental pollution by toxic heavy metals is increasing worldwide, and poses a rising threat to both the environment and to human health.Plants are exposed to heavy metals from various sources: mining and refining of ores, fertilizer and pesticide applications, battery chemicals, disposal of solid wastes(including sewage sludge), irrigation with wastewater, vehicular exhaust emissions and adjacent industrial activity.Heavy metals induce various morphological, physiological, and biochemical dysfunctions in plants, either directly or indirectly, and cause various damaging effects. The most frequently documented and earliest consequence of heavy metal toxicity in plants cells is the overproduction of ROS. Unlike redox-active metals such as iron and copper, heavy metals (e.g, Pb, Cd, Ni, AI, Mn and Zn) cannot generate ROS directly by participating in biological redox reactions such as Haber Weiss/Fenton reactions. However, these metals induce ROS generation via different indirect mechanisms, such as stimulating the activity of NADPH oxidases, displacing essential cations from specific binding sites of enzymes and inhibiting enzymatic activities from their affinity for -SH groups on the enzyme.Under normal conditions, ROS play several essential roles in regulating the expression of different genes. Reactive oxygen species control numerous processes like the cell cycle, plant growth, abiotic stress responses, systemic signalling, programmed cell death, pathogen defence and development. Enhanced generation of these species from heavy metal toxicity deteriorates the intrinsic antioxidant defense system of cells, and causes oxidative stress. Cells with oxidative stress display various chemical,biological and physiological toxic symptoms as a result of the interaction between ROS and biomolecules. Heavy-metal-induced ROS cause lipid peroxidation, membrane dismantling and damage to DNA, protein and carbohydrates. Plants have very well-organized defense systems, consisting of enzymatic and non-enzymatic antioxidation processes. The primary defense mechanism for heavy metal detoxification is the reduced absorption of these metals into plants or their sequestration in root cells.Secondary heavy metal tolerance mechanisms include activation of antioxidant enzymes and the binding of heavy metals by phytochelatins, glutathione and amino acids. These defense systems work in combination to manage the cascades of oxidative stress and to defend plant cells from the toxic effects of ROS.In this review, we summarized the biochemiCal processes involved in the over production of ROS as an aftermath to heavy metal exposure. We also described the ROS scavenging process that is associated with the antioxidant defense machinery.Despite considerable progress in understanding the biochemistry of ROS overproduction and scavenging, we still lack in-depth studies on the parameters associated with heavy metal exclusion and tolerance capacity of plants. For example, data about the role of glutathione-glutaredoxin-thioredoxin system in ROS detoxification in plant cells are scarce. Moreover, how ROS mediate glutathionylation (redox signalling)is still not completely understood. Similarly, induction of glutathione and phytochelatins under oxidative stress is very well reported, but it is still unexplained that some studied compounds are not involved in the detoxification mechanisms. Moreover,although the role of metal transporters and gene expression is well established for a few metals and plants, much more research is needed. Eventually, when results for more metals and plants are available, the mechanism of the biochemical and genetic basis of heavy metal detoxification in plants will be better understood. Moreover, by using recently developed genetic and biotechnological tools it may be possible to produce plants that have traits desirable for imparting heavy meta

Shahid, Muhammad; Pourrut, Bertrand; Dumat, Camille; Nadeem, Muhammad; Aslam, Muhammad; Pinelli, Eric

2014-01-01

280

Volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios: a radiographic study in minipigs  

DEFF Research Database (Denmark)

Objective: The objective of the present study was to learn about the volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone from the iliac crest or the mandible in different ratios in minipigs. Material and methods: Bilateral maxillary sinus floor augmentation was performed in 40 minipigs with: (A) 100% autogenous bone, (B) 75% autogenous bone and 25% Bio-Oss, (C) 50% autogenous bone and 50% Bio-Oss, (D) 25% autogenous bone and 75% Bio-Oss, and (E) 100% Bio-Oss. The autogenous bone graft was harvested from the iliac crest or the mandible and the graft composition was selected at random and placed concomitant with implant placement. Computed tomographies of the maxillary sinuses were obtained preoperatively, immediately postoperatively, and at euthanasia after 12 weeks. The volumetric changes of the graft were estimated using the Cavalieri principle and expressed as mean percentage with a 95% confidence interval (CI). Results: The mean volume of the graft was reduced by (A) 65% (95% CI: 60-70%), (B) 38% (95% CI: 35-41%), (C) 23% (95% CI: 21-25%), (D) 16% (95% CI: 12-21%), and (E) 6% (95% CI: 4-8%). The volumetric reduction was significantly influenced by the ratio of Bio-Oss and autogenous bone (P

Jensen, Thomas; Schou, SØren

2012-01-01

 
 
 
 
281

Volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios : a radiographic study in minipigs  

DEFF Research Database (Denmark)

Objective: The objective of the present study was to learn about the volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone from the iliac crest or the mandible in different ratios in minipigs. Material and methods: Bilateral maxillary sinus floor augmentation was performed in 40 minipigs with: (A) 100% autogenous bone, (B) 75% autogenous bone and 25% Bio-Oss, (C) 50% autogenous bone and 50% Bio-Oss, (D) 25% autogenous bone and 75% Bio-Oss, and (E) 100% Bio-Oss. The autogenous bone graft was harvested from the iliac crest or the mandible and the graft composition was selected at random and placed concomitant with implant placement. Computed tomographies of the maxillary sinuses were obtained preoperatively, immediately postoperatively, and at euthanasia after 12 weeks. The volumetric changes of the graft were estimated using the Cavalieri principle and expressed as mean percentage with a 95% confidence interval (CI). Results: The mean volume of the graft was reduced by (A) 65% (95% CI: 60-70%), (B) 38% (95% CI: 35-41%), (C) 23% (95% CI: 21-25%), (D) 16% (95% CI: 12-21%), and (E) 6% (95% CI: 4-8%). The volumetric reduction was significantly influenced by the ratio of Bio-Oss and autogenous bone (P

Jensen, Thomas; Schou, SØren

2012-01-01

282

Immediate periodontal bone plate changes induced by rapid maxillary expansion in the early mixed dentition: CT findings  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o presente estudo teve como objetivo avaliar alterações das tábuas ósseas vestibulares e linguais decorrentes da expansão rápida da maxila (ERM), em pacientes na dentição mista, por meio de tomografia computadorizada (TC). MÉTODOS: a amostra foi constituída por exames de TC helicoidal [...] , realizados de 22 pacientes com dentição mista, dos 6 aos 9 anos de idade (média de 8,1 anos), com atresia maxilar, tratados com expansores do tipo Haas. Os pacientes foram submetidos a tomografia computadorizada helicoidal antes da expansão e após o período de ativação de parafuso expansor, com 30 dias de intervalo entre as fases T1 e T2. A reconstrução multiplanar foi usada para medir a espessura da tábua óssea vestibular e lingual e a altura da crista óssea alveolar dos dentes posteriores decíduos e dos dentes permanentes. As alterações induzidas pela expansão foram avaliadas usando o teste t pareado (p Abstract in english OBJECTIVE: This study aimed at evaluating buccal and lingual bone plate changes caused by rapid maxillary expansion (RME) in the mixed dentition by means of computed tomography (CT). METHODS: The sample comprised spiral CT exams taken from 22 mixed dentition patients from 6 to 9 years of age ( [...] mean age of 8.1 years) presenting constricted maxillary arch treated with Haas-type expanders. Patients were submitted to spiral CT scan before expansion and after the screw activation period with a 30-day interval between T1 and T2. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal bone crest level of maxillary posterior deciduous and permanent teeth. Changes induced by expansion were evaluated using paired t test (p

Daniela Gamba, Garib; Maria Helena Ocké, Menezes; Omar Gabriel da, Silva Filho; Patricia Bittencourt Dutra dos, Santos.

2014-06-01

283

Immediate periodontal bone plate changes induced by rapid maxillary expansion in the early mixed dentition: CT findings  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o presente estudo teve como objetivo avaliar alterações das tábuas ósseas vestibulares e linguais decorrentes da expansão rápida da maxila (ERM), em pacientes na dentição mista, por meio de tomografia computadorizada (TC). MÉTODOS: a amostra foi constituída por exames de TC helicoidal [...] , realizados de 22 pacientes com dentição mista, dos 6 aos 9 anos de idade (média de 8,1 anos), com atresia maxilar, tratados com expansores do tipo Haas. Os pacientes foram submetidos a tomografia computadorizada helicoidal antes da expansão e após o período de ativação de parafuso expansor, com 30 dias de intervalo entre as fases T1 e T2. A reconstrução multiplanar foi usada para medir a espessura da tábua óssea vestibular e lingual e a altura da crista óssea alveolar dos dentes posteriores decíduos e dos dentes permanentes. As alterações induzidas pela expansão foram avaliadas usando o teste t pareado (p Abstract in english OBJECTIVE: This study aimed at evaluating buccal and lingual bone plate changes caused by rapid maxillary expansion (RME) in the mixed dentition by means of computed tomography (CT). METHODS: The sample comprised spiral CT exams taken from 22 mixed dentition patients from 6 to 9 years of age ( [...] mean age of 8.1 years) presenting constricted maxillary arch treated with Haas-type expanders. Patients were submitted to spiral CT scan before expansion and after the screw activation period with a 30-day interval between T1 and T2. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal bone crest level of maxillary posterior deciduous and permanent teeth. Changes induced by expansion were evaluated using paired t test (p

Daniela Gamba, Garib; Maria Helena Ocké, Menezes; Omar Gabriel da, Silva Filho; Patricia Bittencourt Dutra dos, Santos.

284

Magnetic resonance tomography (MRT) of bone and cartilage transplants in the knee. Transplant morphology and an attempt at a quantitative evaluation of cartilage changes  

International Nuclear Information System (INIS)

MRT control examinations were carried out on 15 patients with allogenic bone-cartilage transplants in the knee. Spin-echo and gradient-echo sequences were obtained by using a flat surface coil. The results were compared with arthroscopic and operative findings. In 8 symptom-free patients, there was inclusion of the bone implant with narrow, but smooth, cartilage. 7 patients with recurrence of symptoms showed various complications such as oedema of the marrow, exudative synovitis, cartilage oedema, degenerative cartilagenous changes with regeneration of fibro-cartilage and localised cartilage defects. Spin-echo sequences were useful for showing bone, whereas gradient-echo sequences proved better for showing changes in the cartilage. MRT can be recommended as the method of choice for the non-invasive control of bone-cartilage transplants. (orig.)

285

{sup 99m}Tc-HDP Bone Scintigraphy Finding of Metastatic Renal Cell Carcinoma Bone Lesion Changed from Hot to Cold Lesion: Comparing with {sup 18}F-FDG PET/CT  

Energy Technology Data Exchange (ETDEWEB)

A 26-year-old man with renal cell carcinoma underwent {sup 99m}Tc-HDP bone scintigraphy for detecting bony metastasis after left total nephrectomy for renal cell carcinoma. {sup 99m}Tc-HDP bone scintigraphy showed small hot lesion in the first lumbar spine. About 12 months later, he underwent spinal MRI for lower back pain. A large mass was seen around spinous process of the first lumbar spine (L1) on spinal MRI and confirmed as metastatic renal cell carcinoma by bone biopsy. {sup 99m}Tc-HDP bone scintigraphy and {sup 18}F-FDG PET/CT were underwent for further evaluation. {sup 99m}Tc-HDP bone scintigraphy showed cold lesion in the first lumbar spine which was initially hot and newly developed hot lesion in the twelfth thoracic spine, and which were shown as hypermetabolic lesions in {sup 18}F-FDG PET/CT. We report a case of bony metastasis from renal cell carcinoma which is changed from hot lesion to cold lesion in {sup 99m}Tc-HDP bone scintigraphy and compare with {sup 18}F-FDG PET/CT.

Seo, Young Duk; Kim, Seong Min; Kim, Kun Ho [Chungnam National University Hospital, Daejeon (Korea, Republic of)

2009-12-15

286

99mTc-HDP Bone Scintigraphy Finding of Metastatic Renal Cell Carcinoma Bone Lesion Changed from Hot to Cold Lesion: Comparing with 18F-FDG PET/CT  

International Nuclear Information System (INIS)

A 26-year-old man with renal cell carcinoma underwent 99mTc-HDP bone scintigraphy for detecting bony metastasis after left total nephrectomy for renal cell carcinoma. 99mTc-HDP bone scintigraphy showed small hot lesion in the first lumbar spine. About 12 months later, he underwent spinal MRI for lower back pain. A large mass was seen around spinous process of the first lumbar spine (L1) on spinal MRI and confirmed as metastatic renal cell carcinoma by bone biopsy. 99mTc-HDP bone scintigraphy and 18F-FDG PET/CT were underwent for further evaluation. 99mTc-HDP bone scintigraphy showed cold lesion in the first lumbar spine which was initially hot and newly developed hot lesion in the twelfth thoracic spine, and which were shown as hypermetabolic lesions in 18F-FDG PET/CT. We report a case of bony metastasis from renal cell carcinoma which is changed from hot lesion to cold lesion in 99mTc-HDP bone scintigraphy and compare with 18F-FDG PET/CT

287

Ossificans myositis: inflammatory changes and contrast enhancement of adjacent bone shown by MR imaging; Myosite ossifiante circonscrite: remaniements osseux deceles en IRM  

Energy Technology Data Exchange (ETDEWEB)

The authors report a case of ossificans myositis, in which magnetic resonance imaging (MRI) showed inflammatory changes of the adjacent bone. T 1 weighted fat saturation sequence with gadolinium injection showed enhancement of medullary and cortical bone. This potentially mistaking pattern must be known, to avoid mis diagnosing with malignant osseous tumor, specially before achievement of the characteristic pattern of zonal maturation and its calcified rim. (authors). 15 refs., 6 figs.

David, H.; Jolles, E.; Le Friant, G.; Silvestre, A.; Sarrazin, J.L.; Gordoliani, Y.S. [Hopital des Armees du Val-de-Grace, 75 - Paris (France)

1995-07-01

288

Time-Resolved Dehydration-Induced Structural Changes in an Intact Bovine Cortical Bone Revealed by Solid-State NMR Spectroscopy  

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Understanding the structure and structural changes of bone, a highly heterogeneous material with a complex hierarchical architecture, continues to be a significant challenge even for high-resolution solid-state NMR spectroscopy. While it is known that dehydration affects mechanical properties of bone by decreasing its strength and toughness, the underlying structural mechanism at atomic-level is unknown. Solid-state NMR spectroscopy, controlled dehydration, and H/D exchange are used for the f...

Zhu, Peizhi; Xu, Jiadi; Sahar, Nadder; Morris, Michael D.; Kohn, David H.; Ramamoorthy, Ayyalusamy

2009-01-01

289

Nanoscale changes in collagen are reflected in physical and mechanical properties of bone at the microscale in diabetic rats.  

Science.gov (United States)

Diabetes detrimentally affects the musculoskeletal system by stiffening the collagen matrix due to increased advanced glycation end products (AGEs). In this study, tibiae and tendon from Zucker diabetic Sprague-Dawley (ZDSD) rats were compared to Sprague-Dawley derived controls (CD) using Atomic Force Microscopy. ZDSD and CD tibiae were compared using Raman Spectroscopy and Reference Point Indentation (RPI). ZDSD bone had a significantly different distribution of collagen D-spacing than CD (p=0.015; ZDSD n=294 fibrils; CD n=274 fibrils) which was more variable and shifted to higher values. This shift between ZDSD and CD D-spacing distribution was more pronounced in tendon (pcreep indentation distance (p=0.040) measured by RPI (n=9 per group) in ZDSD rats suggest a matrix more resistant to indentation under the high stresses associated with RPI at this length scale. There were significant correlations between Raman and RPI measurements in the ZDSD population (n=18 locations) but not the CD population (n=16 locations) indicating that while RPI is relatively unaffected by biological noise, it is sensitive to disease-induced compositional changes. In conclusion, diabetes in the ZDSD rat causes changes to the nanoscale morphology of collagen that result in compositional and mechanical effects in bone at the microscale. PMID:24269519

Hammond, Max A; Gallant, Maxime A; Burr, David B; Wallace, Joseph M

2014-03-01

290

Tomographic Analysis of Reactive Flow Induced Pore Structure Changes in Column Experiments  

International Nuclear Information System (INIS)

We utilize synchrotron X-ray computed microtomography to capture and quantify snapshots in time of dissolution and secondary precipitation in the microstructure of Hanford sediments exposed to simulated caustic waste in flow-column experiments. The experiment is complicated somewhat as logistics dictated that the column spent significant amounts of time in a sealed state (acting as a batch reactor). Changes accompanying a net reduction in porosity of 4% were quantified including: (1) a 25% net decrease in pores resulting from a 38% loss in the number of pores less than < 10-4 MM3 in volume and a 13% increase in the number of pores of larger size; and (2) a 38% decrease in the number of throats. The loss of throats resulted in decreased coordination number for pores of all sizes and significant reduction in the number of pore pathways

291

Deletion of MLCK210 induces subtle changes in vascular reactivity but does not affect cardiac function.  

Science.gov (United States)

Myosin light chain kinase (MLCK) plays a key role in the regulation of actomyosin contraction in a large variety of cells. Two isoforms have been described: a short isoform, widely expressed in smooth muscle cells; and a long isoform (MLCK210), mainly localized in the endothelium. This study investigated the consequences on different cardiovascular parameters of MLCK210 gene deletion using MLCK210 knockout mice and of pharmacological inhibition of the kinase using a specific MLCK inhibitor. Deletion of MLCK210 did not affect systolic blood pressure and heart rate or echocardiographic measurements. Electrocardiographic analysis showed neither atrio- nor intraventricular conduction or repolarization defects. Ex vivo responses of aortic rings to vasoconstrictor and vasodilator agonists were not modified in MLCK210 null mice. However, deletion of MLCK210 attenuated shear stress-induced dilation and produced changes in the balance of endothelial-relaxing factors of small mesenteric arteries (SMA). In particular, a reduced flow-mediated NO-dependent dilation was observed. However, it was partially compensated by enhanced indomethacin-sensitive dilation. No significant changes were detected in the endothelium-derived hyperpolarizing component of the vasodilator response. The above effects of MLCK210 gene deletion were confirmed in SMA from wild-type mice by the use of the MLCK enzymatic inhibitor MMZ-10-057. In summary, deletion of MLCK210 was not associated with abnormalities of main in vivo cardiovascular parameters in mice. This study demonstrates a role for MLCK210 in the regulation of flow-dependent dilation in SMA. PMID:16055522

Ohlmann, Patrick; Tesse, Angela; Loichot, Cécile; Ralay Ranaivo, Hantamalala; Roul, Gerald; Philippe, Claude; Watterson, D Martin; Haiech, Jacques; Andriantsitohaina, Ramaroson

2005-12-01

292

Changes in salivary hormones, immunoglobulin A, and C-reactive protein in response to ultra-endurance exercises.  

Science.gov (United States)

The aim of the study was to determine the influence of the exercise duration on the changes in salivary stress markers in response to ultra-endurance exercises. The study was developed in 2 ultra-endurance exercise tests: the Ultra-trail Serra de Tramuntana (UTST), a 104 km ultra-marathon competition (n = 64) and the 25 km Cabrera Open Water Race (COWR) (n = 43). Participants in the COWR completed the 25 km at a constant pace of 3 km/h (3K group) or 2.5 km /h (2.5K group). Saliva samples were taken before and after the exercises. Salivary flow rate as well as cortisol, testosterone, C-reactive protein (CRP), and immunoglobulin A (IgA) levels were measured. Salivary flow rate decreased after the UTST but increased after the COWR. The UTST induced significant increases in cortisol and CRP levels and decreases in testosterone and IgA levels. Furthermore, a negative correlation was found between the time the athletes took to complete the exercise and the changes in salivary cortisol. After the COWR, higher increases in salivary cortisol levels were observed in the 3K group than in the 2.5K group. A significant effect of exercise decreasing testosterone and IgA levels was observed in both groups. No changes in the CRP levels were observed during the COWR. In conclusion, shorter times to complete the ultra-endurance exercise were associated with higher increases in cortisol. However, no relationships were found between the time to complete the exercises and the changes in testosterone, CRP, and IgA levels. PMID:24766238

Tauler, Pedro; Martinez, Sonia; Moreno, Carlos; Martínez, Pau; Aguilo, Antoni

2014-05-01

293

Histomorphometric analysis of the temporal bone after change of direction of force vector of mandible: an experimental study in rabbits  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: The present study aimed at performing a histological evaluation of the response of temporal bone tissue to a change of direction of the force vector of the mandible in relation to the base of the skull. MATERIAL AND METHODS: Adult rabbits were assigned into four groups with two control a [...] nd four experimental animals in each group. experimental animals underwent surgery, which resulted in a change of direction of the force vector on the right temporomandibular joint. Samples were collected after 15, 30, 60 and 90 days for histological analysis. RESULTS: In the two-way analysis of variance, the effect of group and time was statistically significant (p

Edela, Puricelli; Deise, Ponzoni; Jéssica Cerioli, Munaretto; Adriana, Corsetti; Mauro Gomes Trein, Leite.

294

Changes in bone mineral density and body composition of children with well-controlled homocystinuria caused by CBS deficiency.  

Science.gov (United States)

Homocystinuria due to cystathionine ?-synthase (CBS) deficiency is an inherited disorder of the metabolism of methionine. Clinical manifestations include mental retardation, dislocation of the optic lens, vascular lesions, arterial and venous thromboembolism, skeletal abnormalities, and osteoporosis. Most homocystinuria patients diagnosed in adulthood have severe osteoporosis, and homocystinuria is frequently mentioned as a cause of osteoporosis. Good control of plasma homocysteine may prevent or delay some of these complications. However, the effectiveness of bone mineral density (BMD) gain or fracture prevention has not been addressed. Here, we describe changes in BMD and body composition in 5 CBS deficiency patients who were diagnosed at young age and were managed with good metabolic control. We found that the BMD of each region was within the normal range. BMD gain was adequate and the patients had no significant change in skeletal morphology. PMID:23685761

Lim, J S; Lee, D H

2013-09-01

295

Histomorphometric analysis of the temporal bone after change of direction of force vector of mandible: an experimental study in rabbits  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: The present study aimed at performing a histological evaluation of the response of temporal bone tissue to a change of direction of the force vector of the mandible in relation to the base of the skull. MATERIAL AND METHODS: Adult rabbits were assigned into four groups with two control a [...] nd four experimental animals in each group. experimental animals underwent surgery, which resulted in a change of direction of the force vector on the right temporomandibular joint. Samples were collected after 15, 30, 60 and 90 days for histological analysis. RESULTS: In the two-way analysis of variance, the effect of group and time was statistically significant (p

Edela, Puricelli; Deise, Ponzoni; Jéssica Cerioli, Munaretto; Adriana, Corsetti; Mauro Gomes Trein, Leite.

2012-10-01

296

Pulmonary complications and respiratory function changes after bone marrow transplantation in children.  

Science.gov (United States)

We prospectively assessed the frequency of pulmonary complications and the natural course of lung function after bone marrow transplantation (BMT), as well as the effect of several risk factors in a homogeneous group of 39 children who underwent allogeneic or autologous BMT for haematological malignancies between 1992 and 1995. Four patients developed pneumonia within the first 3 months and three 3-6 months after BMT. A considerable percentage of acute bronchitis was recorded throughout the follow-up. Three patients died after the 6 month visit because of pneumonia (two patients) and pulmonary aspergillosis (one patient). No patients had obstructive lung disease syndrome. At 3 months after BMT, forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and transfer factor of the lung for carbon monoxide (TL,CO) significantly decreased, but FEV1/FVC ratio and maximal expiratory flow at 25% of FVC remained unchanged, suggesting a restrictive defect with diffusion impairment. At 18 months, there was a progressive recovery in lung function, although only 11 patients had normalized. Seropositivity for cytomegalovirus had a significant effect on lung function whereas graft-versus-host disease also had an effect, although it was not statistically significant. Baseline respiratory function, type of transplant, type of conditioning regimen and respiratory infections did not significantly affect the outcome of BMT. The high frequency of severe lung function abnormalities found in this study, suggests a careful functional monitoring in all subjects undergoing bone marrow transplantation, even in the absence of respiratory symptoms. PMID:9387957

Fanfulla, F; Locatelli, F; Zoia, M C; Giorgiani, G; Bonetti, F; Spagnolatti, L; Cerveri, I

1997-10-01

297

Changing patterns of AIDS: impact on the indications and diagnostic yield of bone marrow biopsies  

Directory of Open Access Journals (Sweden)

Full Text Available After the advent of HAART, the clinical course of HIV infection has dramatically improved. Therefore, it seems appropriate to reevaluate the performance of bone marrow biopsy (BMB as a diagnostic tool. The aim of the present study was to compare the reasons for performing a BMB and its diagnostic yield in HIV-patients before and after HAART. A total of 165 BMB specimens obtained from HIV-infected patients receiving care at the Hospital of Universidade Federal do Rio de Janeiro in two different periods (1986-1994 and 1999-2004 were analysed. The main reason for BMB examination in the first period was fever (88%, which decreased in the second period (57%, p < 0.0001, when cytopenia (51% was the leading reason for BMB, whereas in the first period it accounted for only 30% (p = 0.008. A definitive diagnosis (infection, granulomas or lymphomas was obtained in 28% of patients in the first period and in 19% during the second period (p = 0.20. The diagnosis turned out as infections decreased from 16% in period 1 to 2% in period 2 (p = 0.003. Despite the the limitations in the evaluation of fever, the use of BMB must be considered on an individual basis, whenever less invasive alternatives have been exhausted, and should be complemented by a bone marrow aspiration for microbiological studies.

José Carlos Morais

2010-08-01

298

Changes in human bone marrow colony-forming cells following chemotherapy using an agar diffusion-chamber technique  

International Nuclear Information System (INIS)

Studies have been made of the effects of cyclophosphamide on the early granulocytic precursor cells in the marrow of patients receiving intermittent high doses (5 g) of the drug. This study was designed to investigate the effect of a single cytotoxic agent on normal granulocytic precursor cells; measurements have been made of the initial cytotoxicity, recovery, and changes in proliferation rate. The growth of granulocytic colonies was assayed in agar diffusion chambers. For this, bone marrow cells were suspended in semisolid agar medium, introduced into diffusion chambers for intraperitoneal incubation in radiated (900 rad 60Co ?) mice. The colonies present in the agar were scored 8-9 days later. In addition to measuring the effect of treatment on the colony-forming capacity of the patients' marrow, full dose-response curves were obtained by injecting graded doses of cyclophosphamide into chamber-bearing mice--the method allows some account to be taken of the continuous changes in drug activity, which occurs during its degradation in vivo. Comparison of these results with measurements of the sensitivity of mouse femoral cells under the same conditions or exposed to cyclophosphamide in situ in the donor mouse has been used to detect any effect of the culture environment or the response of the cells. Following treatment with cyclophosphamide, the incidence of colony precursor cells in the patients' marrow has been monitored. Changes in the proliferation rate of these cells during the recovery period have also been estimated by measuring their sensitivity to the S-phase specific drug, cytosine arabinoside. Information on the timing of changes in the incidence and proliferation rate of granulocytic precursor cells may provide guidelines for improving schedules of treatment in an attempt to reduce the attendant bone marrow toxicity

299

Aneurysmal bone cyst of the frontal bone  

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Full Text Available Background. Aneurysmal bone cyst (ABC is a benign, expansive, osteolytic lesion that mainly occurs in young people, and involves the skull bones only exceptionally. The origin of ABC is controversial: secondary reactive bone lesion, or primary disease that represents an independent nosological entity. Blunt head trauma was suggested as a possible etiological factor. Case report. A case of a 19-year old man with primary ABC of the right frontal bone was reported. The lesion was totally excised through frontal craniotomy, and the skull bone defect primarily reconstructed with an acrilate cranioplasty. Five years after the surgery, the patient was without signs of local recurrence. Conclusion. Clinical and neuroradiological presentation of the skull ABC was not specific. Pathohistology confirmed the diagnosis. Total excision was the treatment of choice.

Peri? Predrag

2005-01-01

300

Evaluation of sequential FDG-PET/CT for monitoring bone metastasis of breast cancer during therapy. Correlation between morphological and metabolic changes with tumor markers  

International Nuclear Information System (INIS)

The purpose of this study was to clarify the significance of positron emission tomography (PET) and computed tomography (CT) findings for evaluating the bone metastasis of breast cancer during therapy. Forty-seven patients with bone metastases from breast cancer who underwent sequential 18F-flourodeoxyglucose (FDG)-PET/CT studies during therapy were enrolled. A total of 771 lesions were identified. The changes in the PET and CT findings were compared with the tumor marker levels in each patient by calculating the weighted kappa value. The correlation between the PET and CT findings was examined for each lesion by an adjusted Chi-square test. The change in the tumor marker levels was substantially correlated with the PET findings and moderately correlated with the CT findings (weighted kappa=0.780 and 0.585 for quadratic weighting, respectively). An increase in FDG uptake was correlated with lytic changes on the CT images (62/65, 95.4%, p<0.05). Sclerotic changes suggested improvement, but sclerosis and progression occurred at the same time in some lesions. Changes of FDG uptake are useful for evaluating individual bone metastases in cases of breast cancer during therapy. Lytic change on CT images suggests progression of bone metastasis. The lysis-progression/sclerosis-improvement pattern was observed in the majority of subjects, but a sclerosis-progression pattern was also observed. The hybrid pattern of increase of FDG uptake on PET/lytic change on CT is m FDG uptake on PET/lytic change on CT is most accurate to show progression of bone metastases. Assessments of these processes during therapy are necessary for the precise evaluation of bone metastases. (author)

 
 
 
 
301

The influence of a reflector on the reactivity change of a collapsing fuel-bubble mixture in a melted fast breeder reactor core  

International Nuclear Information System (INIS)

A hypothetical loss-of-coolant accident with core meltdown in a sodium-cooled fast breeder is considered. In the course of the accident, steel bubbles collapse in the fuel-steel mixture, changing neutron leakage, and therefore also reactivity. Whereas previous investigations considered unreflected systems only, the present work considers the influence of the reflector. Chapters I and II are introductory. In Chapter III the reactivity change from collapsing bubbles is treated by a one-group diffusion theory. The resulting equations are evaluated in Chapter IV for a hypothetical reactor core. A comparison with available Monte Carlo calculation shows satisfactory agreement. The influence of the reflector on reactivity is considered as a function of bubble radius and core dimensions and discussed. (G.Q.)

302

Changing patterns of AIDS: impact on the indications and diagnostic yield of bone marrow biopsies  

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Full Text Available SciELO Brazil | Language: English Abstract in english After the advent of HAART, the clinical course of HIV infection has dramatically improved. Therefore, it seems appropriate to reevaluate the performance of bone marrow biopsy (BMB) as a diagnostic tool. The aim of the present study was to compare the reasons for performing a BMB and its diagnostic y [...] ield in HIV-patients before and after HAART. A total of 165 BMB specimens obtained from HIV-infected patients receiving care at the Hospital of Universidade Federal do Rio de Janeiro in two different periods (1986-1994 and 1999-2004) were analysed. The main reason for BMB examination in the first period was fever (88%), which decreased in the second period (57%, p

José Carlos, Morais; Marcel, Machado; Irene, Biasoli; Paulo Feijó, Barroso; Cristiane, Milito; Nelson, Spector.

303

Reactive oxygen species produced in mitochondria are involved in age-dependent changes of hematopoietic and mesenchymal progenitor cells in mice. A study with the novel mitochondria-targeted antioxidant SkQ1.  

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Lifelong treatment of mice with the effective mitochondria-targeted antioxidant SkQ1 [10-(6'-plastoquinonyl) decyltriphenylphosphonium] does not affect hematopoietic stem cells (HSC) and more differentiated hematopoietic progenitors but significantly decelerates age-dependent changes in peripheral blood. During the first 13 months, SkQ1 (0.9 or 28.8 nmol/kg day) prevents age-dependent myeloid shift (increase in the proportion of granulocytes and decrease in the proportion of lymphocytes). During the next year of treatment the effect disappears, and the hemogram of 2-year-old treated mice does not differ from the control. The number of mesenchymal stem cells (MSC) in the bone marrow does not change during 2 years of treatment with SkQ1, but the concentration of MSC progeny fibroblast colony-forming units (CFU-F) increases with dose of SkQ1. The concentration of CFU-F after 1 and 2 years treatment with SkQ1 is twice higher than in young mice. Our data indicate that the stromal environment of hematopoietic cells could be the primary target of age-dependent changes mediated by reactive oxygen species produced in mitochondria. The anti-aging effects of SkQ1 described here are in perfect agreement with the inhibitory effects of this antioxidant on aging observed in the other models. PMID:20600239

Shipounova, I N; Svinareva, D A; Petrova, T V; Lyamzaev, K G; Chernyak, B V; Drize, N I; Skulachev, V P

2010-06-01

304

Anorexia Nervosa and Bone  

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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

Misra, Madhusmita; Klibanski, Anne

2014-01-01

305

Effect of Spinal Degenerative Changes on Volumetric Bone Mineral Density of the Central Skeleton as Measured by Quantitative Computed Tomography  

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Purpose: To evaluate the impact of degenerative changes due to osteoarthritis (OA) at the spine on volumetric bone mineral density (BMD) as measured by volumetric quantitative computed tomography (vQCT). Material and Methods: Eighty-four elderly women (mean age 73 ±6 years), comprising 33 with vertebral fractures assessed by radiographs and 51 without vertebral fractures, were studied. Trabecular, cortical, and integral BMD were examined at the spine and hip using a helical CT scanner and were compared to dual X-ray absorptiometry (DXA) measurements at the same sites. OA changes visible on the radiographs were categorized into two grades according to severity. Differences in BMD measures obtained in the two groups of patients defined by OA grade using the described radiologic methods were compared using analysis of variance. Standardized difference (effect sizes) was also compared between radiologic methods. Results: Spinal trabecular BMD did not differ significantly between OA grade 0 and OA grade. Spinal cortical and integral BMD measures showed statistically significant differences, as did the lumbar spine DXA BMD measurement (13%, P?0.02). The QCT measurements at the hip were also higher in OA subjects. Femoral trabecular BMD was 3-15% higher in OA grade subjects than in OA grade 0 subjects. The cortical BMD measures in the CTTOTFEM and CTTROCH ROI's were also higher in the OA subjects. The integral QCT BMD measures in the hip s integral QCT BMD measures in the hip showed difference between grades OA and 0. The DXA measurements in the neck and trochanter ROI's showed smaller differences (9 and 1%, respectively). There were no statistically significant differences in bone size. Conclusion: There is no evidence supporting that trabecular BMD measurements by QCT are influenced by OA. Instead, degenerative changes have an effect on both cortical and integral QCT, and on DXA at the lumbar spine and the hip. For subjects with established OA, assessment of BMD by volumetric QCT may be suggested

306

Changes in protein expression and distribution of spinal CCR2 in a rat model of bone cancer pain.  

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Accumulating evidence suggests that chemokine C-C motif receptor 2 (CCR2) plays an important role in neuropathic pain. It has been shown that spinal CCR2 is upregulated in several neuropathic pain models and expressed by neuronal and glial cells in the spinal cord. In this study, we investigated the expression changes and cellular localization of spinal CCR2 in a rat model of bone cancer induced by Walker 256 cell inoculation. The present results indicated that mechanical allodynia progressively increased in bone cancer pain (BCP) rats. Western blot and immunohistochemical analysis demonstrated that the expression of CCR2 in the spinal cord was significantly increased on day 6, 12, and 18 in BCP rats, with a peak on day 6. Furthermore, double immunofluorescence labeling indicated that CCR2 was expressed by both microglia and neurons in the spinal cord. These results suggest that CCR2 may be involved in the development of BCP, and that targeting CCR2 may be a new strategy for the treatment of BCP. PMID:23511129

Hu, Ji-Hua; Wu, Meng-Yao; Tao, Min; Yang, Jian-Ping

2013-05-01

307

Resistive and reactive changes to the impedance of intracortical microelectrodes can be mitigated with polyethylene glycol under acute in vitro and in vivo settings  

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Full Text Available The reactive response of brain tissue to implantable intracortical microelectrodes is thought to negatively affect their recordable signal quality and impedance, resulting in unreliable longitudinal performance. The relationship between the progression of the reactive tissue into a glial scar and the decline in device performance is unclear. We show that exposure to a model protein solution in vitro and acute implantation result in both resistive and capacitive changes to electrode impedance, rather than purely resistive changes. We also show that applying 4000 MW polyethylene glycol (PEG prevents impedance increases in vitro, and reduces the percent change in impedance in vivo following implantation. Our results highlight the importance of considering the contributions of non-cellular components to the decline in neural microelectrode performance, and present a proof of concept for using a simple dip-coated PEG film to modulate changes in microelectrode impedance.

SalahSommakia

2014-08-01

308

Changes in High-sensitivity C-reactive Protein Levels after Laparoscopic Gastric Stapling Procedures versus Laparoscopic Gastric Banding.  

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Obesity, hypertension, diabetes, and hyperlipidemia are risk factors for the development of coronary artery disease. High-sensitivity C-reactive protein (hs-CRP) is an inflammatory biomarker that has been shown to be an independent predictor for cardiovascular risk. The aim of the current study was to examine the changes in cardiovascular risk profile in morbidly obese patients who underwent laparoscopic gastric stapling procedures (bypass and sleeve) compared with laparoscopic gastric banding. Levels of hs-CRP were measured preoperatively and at 12 to 24 months postoperatively. Based on hs-CRP levels, cardiovascular risk was categorized as low (less than 1 mg/L), moderate (1 to 3 mg/L), or high (greater than 3 mg/L). A total of 52 patients underwent gastric stapling procedures and 49 underwent gastric banding and both had preoperative and postoperative hs-CRP levels measured. There were no significant differences in age, gender, or preoperative body mass index (BMI) between groups. At baseline, 48.0 per cent of patients undergoing gastric stapling and 38.8 per cent of patients undergoing gastric banding had moderate or high cardiovascular risk. BMI at 24 months was significantly lower in the gastric stapling compared with the gastric banding group (30.4 ± 5.4 vs 36.1 ± 5.5 kg/m(2), respectively, P bariatric surgery, but a more pronounced improvement occurred in patients who underwent gastric stapling procedures. PMID:25264657

Gebhart, Alana; Young, Monica; Villamere, James; Shih, Anderson; Nguyen, Ninh T

2014-10-01

309

Bone marrow edema-like lesions change in volume in the majority of patients with osteoarthritis; associations with clinical features  

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It has been suggested that bone marrow edema-like (BME) lesions in the knee are associated with progression of osteoarthritis (OA). The purpose of our study in patients with OA was to evaluate prospectively changes of BME lesions over 2 years and their relationship with clinical features. Magnetic resonance (MR) images of the knee were obtained from 182 patients (20% male; aged 43-76 years; mean age 59 years) who had been diagnosed with familial symptomatic OA at multiple joint sites. MR images were made at baseline and at 2 years follow-up. BME lesions in 2 years were associated with clinical features assessed by Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scores. A total of 327 BME lesions were recorded. Total size of BME lesions changed in 90 patients (66%). Size of individual lesions changed in 147 foci (45%): new lesions appeared in 69 (21%), existing lesions disappeared in 32 (10%), increased in size in 26 (8%) and decreased in size in 20 (6%) lesions. Increase or decrease of BME lesions, over a 2-year time period, was not associated with severity of WOMAC scores. BME lesions fluctuated in the majority of patients with OA over a 2-year time period. These changes were not associated with severity of WOMAC scores at the study end point. (orig.)

310

Phosphate-based glass fiber vs. bulk glass: Change in fiber optical response to probe in vitro glass reactivity.  

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This paper investigates the effect of fiber drawing on the thermal and structural properties as well as on the glass reactivity of a phosphate glass in tris(hydroxymethyl)aminomethane-buffered (TRIS) solution and simulated body fluid (SBF). The changes induced in the thermal properties suggest that the fiber drawing process leads to a weakening and probable re-orientation of the POP bonds. Whereas the fiber drawing did not significantly impact the release of P and Ca, an increase in the release of Na into the solution was noticed. This was probably due to small structural reorientations occurring during the fiber drawing process and to a slight diffusion of Na to the fiber surface. Both the powders from the bulk and the glass fibers formed a Ca-P surface layer when immersed in SBF and TRIS. The layer thickness was higher in the calcium and phosphate supersaturated SBF than in TRIS. This paper for the first time presents the in vitro reactivity and optical response of a phosphate-based bioactive glass (PBG) fiber when immersed in SBF. The light intensity remained constant for the first 48h after which a decrease with three distinct slopes was observed: the first decrease between 48 and 200h of immersion could be correlated to the formation of the Ca-P layer at the fiber surface. After this a faster decrease in light transmission was observed from 200 to ~425h in SBF. SEM analysis suggested that after 200h, the surface of the fiber was fully covered by a thin Ca-P layer which is likely to scatter light. For immersion times longer than ~425h, the thickness of the Ca-P layer increased and thus acted as a barrier to the dissolution process limiting further reduction in light transmission. The tracking of light transmission through the PBG fiber allowed monitoring of the fiber dissolution in vitro. These results are essential in developing new bioactive fiber sensors that can be used to monitor bioresponse in situ. PMID:24582246

Massera, J; Ahmed, I; Petit, L; Aallos, V; Hupa, L

2014-04-01

311

Histological and radiological changes in cranial bone in the presence of bone wax / Alterações histológicas e radiológicas no osso craniano na presença de cera de osso  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: Quantificar a formação óssea da região da calvaria de ratos Wistar submetidos à craniotomia com a utilização de cera de osso como agente hemostático. MÉTODOS: Cirurgia para realizar um defeito ósseo craniano bilateral, simétrico (área: 18 mm²) e com espessura total foi realizado em oito an [...] imais. O lado direito do crânio permaneceu aberto e as extremidades do defeito ósseo do lado esquerdo foram recobertas com cera de osso. O crânio foi submetido à avaliação radiológica imediatamente após a cirurgia e 12 semanas após a cirurgia com a utilização de tomografia computadorizada. As áreas dos defeitos ósseos foram medidas através de imagens tridimensionais e utilizando o programa de computador Magics 13.0 (Materialise-Belgic, software CAD). RESULTADOS: A quantidade média de formação óssea no lado esquerdo e direito foi respectivamente de 4.85 mm² e 8.16 mm². Diferença estatisticamente significante foi observada entre o lado direito e esquerdo. CONCLUSÕES: A cera de osso diminuiu significativamente a formação óssea nos defeitos ósseos em modelo animal. Abstract in english PURPOSE: To quantify the amount of bone formation in the calvarial region of Wistar rats after craniotomy using bone wax as a haemostatic agent. METHODS: Surgery to produce bilateral, symmetric, full-thickness cranial defects (area: 18 mm²) was performed in eight animals. The right side of the crani [...] um remained open and the edges of the left side osseous defect was covered with bone wax. Calvaria were imaged immediately after surgery and 12 weeks postoperatively by computerized tomography. The areas of the bone defects were measured in three-dimensional images using Magics 13.0 (Materialise-Belgic, software CAD). RESULTS: The average amount of bone formation on the left and right side respectively was 4.85 mm² and 8.16 mm². Statistically significant differences between the amount of bone formation on the left and right sides were seen. CONCLUSIONS: Bone wax significantly diminishes the rate of bone formation in calvarial defects in a rat model.

Cassio Eduardo, Raposo-Amaral; Ana Beatriz Albino de, Almeida; Gustavo, Paschoal; Daniela Franco, Bueno; Luiz Carlos, Vulcano; Maria Rita, Passos-Bueno; Nivaldo, Alonso.

2011-08-01

312

Cardiovascular changes after PMMA vertebroplasty in sheep: the effect of bone marrow removal using pulsed jet-lavage.  

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Clinically, the displacement of intravertebral fat into the circulation during vertebroplasty is reported to lead to problems in elderly patients and can represent a serious complication, especially when multiple levels have to be treated. An in vitro study has shown the feasibility of removing intravertebral fat by pulsed jet-lavage prior to vertebroplasty, potentially reducing the embolization of bone marrow fat from the vertebral bodies and alleviating the cardiovascular changes elicited by pulmonary fat embolism. In this in vivo study, percutaneous vertebroplasty using polymethylmethacrylate (PMMA) was performed in three lumbar vertebrae of 11 sheep. In six sheep (lavage group), pulsed jet-lavage was performed prior to injection of PMMA compared to the control group of five sheep receiving only PMMA vertebroplasty. Invasive recording of blood pressures was performed continuously until 60 min after the last injection. Cardiac output and arterial blood gas parameters were measured at selected time points. Post mortem, the injected cement volume was measured using CT and lung biopsies were processed for assessment of intravascular fat. Pulsed jet-lavage was feasible in the in vivo setting. In the control group, the injection of PMMA resulted in pulmonary fat embolism and a sudden and significant increase in mean pulmonary arterial pressure. Pulsed jet-lavage prevented any cardiovascular changes and significantly reduced the severity of bone marrow fat embolization. Even though significantly more cement had been injected into the lavaged vertebral bodies, significantly fewer intravascular fat emboli were identified in the lung tissue. Pulsed jet-lavage prevented the cardiovascular complications after PMMA vertebroplasty in sheep and alleviated the severity of pulmonary fat embolism. PMID:20725752

Benneker, Lorin M; Krebs, Jörg; Boner, Vanessa; Boger, Andreas; Hoerstrup, Simon; Heini, Paul F; Gisep, Armando

2010-11-01

313

Cardiovascular changes after PMMA vertebroplasty in sheep: the effect of bone marrow removal using pulsed jet-lavage  

Science.gov (United States)

Clinically, the displacement of intravertebral fat into the circulation during vertebroplasty is reported to lead to problems in elderly patients and can represent a serious complication, especially when multiple levels have to be treated. An in vitro study has shown the feasibility of removing intravertebral fat by pulsed jet-lavage prior to vertebroplasty, potentially reducing the embolization of bone marrow fat from the vertebral bodies and alleviating the cardiovascular changes elicited by pulmonary fat embolism. In this in vivo study, percutaneous vertebroplasty using polymethylmethacrylate (PMMA) was performed in three lumbar vertebrae of 11 sheep. In six sheep (lavage group), pulsed jet-lavage was performed prior to injection of PMMA compared to the control group of five sheep receiving only PMMA vertebroplasty. Invasive recording of blood pressures was performed continuously until 60 min after the last injection. Cardiac output and arterial blood gas parameters were measured at selected time points. Post mortem, the injected cement volume was measured using CT and lung biopsies were processed for assessment of intravascular fat. Pulsed jet-lavage was feasible in the in vivo setting. In the control group, the injection of PMMA resulted in pulmonary fat embolism and a sudden and significant increase in mean pulmonary arterial pressure. Pulsed jet-lavage prevented any cardiovascular changes and significantly reduced the severity of bone marrow fat embolization. Even though significantly more cement had been injected into the lavaged vertebral bodies, significantly fewer intravascular fat emboli were identified in the lung tissue. Pulsed jet-lavage prevented the cardiovascular complications after PMMA vertebroplasty in sheep and alleviated the severity of pulmonary fat embolism. PMID:20725752

Benneker, Lorin M.; Krebs, Jorg; Boner, Vanessa; Boger, Andreas; Hoerstrup, Simon; Heini, Paul F.

2010-01-01

314

Cytogenetic Changes Associated with Myelodysplastic Syndrome Affecting Bone Marrow Engraftment Analysis  

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In vitro amplification of polymorphic genetic markers, especially short tandem repeats (STRs), has become standard laboratory practice in the monitoring of allogeneic bone marrow transplant patients. After initial analysis of donor and recipient samples at multiple loci before transplantation, one or more loci are used to follow engraftment status in subsequent specimens. We describe an unusual pattern of STRs in a transplanted patient with a prior history of refractory acute myelogenous leukemia. DNA chimerism studies showed a lack of engraftment at 1 and 2 months after transplantation. Atypical minor peaks occurred at each of three STR loci in the pre-transplant and 2-month post-transplant recipient samples. However, these peaks were of equal amplitude as the major corresponding allele in the 1-month post-transplant sample. A history of myelodysplasia with specific chromosomal deletions before the patient’s acute myelogenous leukemia diagnosis appears to explain the spurious peaks. STR analysis of blood and archival paraffin-embedded tissues collected from the patient at various time points before transplantation reflected the evolution, progression, and response to therapy of the myelodysplasia. The case illustrates the need for comprehensive evaluation of pertinent clinical and laboratory data during engraftment monitoring to identify potential sources for error in interpretation of STR analysis. PMID:16645218

Dunn, Terence; Allen, Richard; Bates, Francesca; Kurkjian, Carla; Kamble, Rammurti; Kharfan-Dabaja, Mohamed

2006-01-01

315

Identifying compositional and structural changes in spongy and subchondral bone from the hip joints of patients with osteoarthritis using Raman spectroscopy  

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Raman microspectroscopy was used to examine the biochemical composition and molecular structure of extracellular matrix in spongy and subchondral bone collected from patients with clinical and radiological evidence of idiopathic osteoarthritis of the hip and from patients who underwent a femoral neck fracture, as a result of trauma, without previous clinical and radiological evidence of osteoarthritis. The objectives of the study were to determine the levels of mineralization, carbonate accumulation and collagen quality in bone tissue. The subchondral bone from osteoarthritis patients in comparison with control subject is less mineralized due to a decrease in the hydroxyapatite concentration. However, the extent of carbonate accumulation in the apatite crystal lattice increases, most likely due to deficient mineralization. The alpha helix to random coil band area ratio reveals that collagen matrix in subchondral bone is more ordered in osteoarthritis disease. The hydroxyapatite to collagen, carbonate apatite to hydroxyapatite and alpha helix to random coil band area ratios are not significantly changed in the differently loaded sites of femoral head. The significant differences also are not visible in mineral and organic constituents' content in spongy bone beneath the subchondral bone in osteoarthritis disease.

Buchwald, Tomasz; Niciejewski, Krzysztof; Kozielski, Marek; Szybowicz, Miros?aw; Siatkowski, Marcin; Krauss, Hanna

2012-01-01

316

Alcoholic liver disease and changes in bone mineral density / Enfermedad hepática alcohólica y alteraciones de la densidad mineral ósea  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: English Abstract in spanish La osteoporosis y la osteopenia son alteraciones de la densidad mineral ósea (DMO) que se desarrollan frecuentemente en la enfermedad hepática crónica (EHC). Dichas alteraciones han sido estudiadas predominantemente en la enfermedad colestásica crónica y en la cirrosis hepática. El consumo de alcoho [...] l es un factor de riesgo independiente para la aparición de osteoporosis, cuya prevalencia estimada en pacientes con enfermedad hepática por alcohol (EHA) varía entre un 5 % y un 40 %. La pérdida de DMO en la EHA se produce por un disbalance entre formación y resorción ósea. Su etiopatogenia es multifactorial y comprende la toxicidad del alcohol sobre el hueso, las alteraciones endocrinológicas y nutricionales secundarias al alcoholismo y el déficit de osteocalcina, vitamina D e IGF-1, entre otras. El diagnóstico de las alteraciones de la DMO en la EHA se basa en su medición mediante densitometría ósea. El tratamiento incluye el abandono del alcohol y medidas generales de tipo nutricional, abandono del tabaco y ejercicio físico. La suplementación con calcio y vitamina D se recomienda en todos los pacientes con EHA y osteoporosis. Los bisfosfonatos son los principales fármacos para el tratamiento específico de esta entidad. Otras alternativas son el raloxifeno, el tratamiento hormonal sustitutivo y la calcitonina. La presente revisión abordará los aspectos más relevantes para el manejo clínico de las alteraciones de la DMO en el contexto de la EHA, incluyendo su prevalencia, etiopatogenia y diagnóstico. Por otra parte, se efectuará una revisión del tratamiento de la osteoporosis en la EHC en general, incidiendo en los aspectos específicos relacionados con la pérdida de masa ósea en la EHA. Abstract in english Osteoporosis and osteopenia are alterations in bone mineral density (BMD) that frequently occur in the context of chronic liver disease (CLD). These alterations have been studied predominantly in chronic cholestatic disease and cirrhosis of the liver. Alcohol consumption is an independent risk facto [...] r for the onset of osteoporosis, whose estimated prevalence in patients with alcoholic liver disease (ALD) ranges between 5 % and 40 %. The loss of BMD in ALD is the result of an imbalance between bone formation and resorption. Its pathogenesis is multifactorial and includes the toxic effects of alcohol on bone and endocrine and nutritional disorders secondary to alcoholism and a deficiency of osteocalcin, vitamin D and insulin growth factor-1. The diagnosis of BMD alterations in ALD is based on its measurement using bone densitometry. Treatment includes smoking and alcohol cessation and general measures such as changes in nutrition and exercise. Calcium and vitamin D supplements are recommended in all patients with ALD and osteoporosis. Bisphosphonates are the most commonly prescribed drugs for the specific treatment of this condition. Alternatives include raloxifene, hormone replacement therapy and calcitonin. This review will address the most important aspects involved in the clinical management of abnormal BMD in the context of ALD, including its prevalence, pathogenesis and diagnosis. We will also review the treatment of osteoporosis in CLD in general, focusing on specific aspects related to bone loss in ALD.

Germán, López-Larramona; Alfredo J., Lucendo; Laura, González-Delgado.

2013-12-01

317

The Study on Bone Mineral Density Measurement Error in Accordance with Change in ROI by Utilizing Dual Energy X-ray Absorptiometry  

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Dual Energy X-ray Absorptiometry(DEXA) is commonly used to diagnose Osteoporosis. The errors of DEXA bone density operation are caused by operator, bone mineral density meter, blood testing, patient. We focus on operator error then study about how much influence operator's region of intest(ROI) in bone testing result. During from March to July in 2011. 50 patients ware selected respectively from 30, 40, 50, 60, and 70 age groups who came to Korea University Medical Center(KUMC) for their Osteoporosis treatment. A-test was performed with usually ROI and B-test was performed with most widely ROI. Then, We compare A-test and B-test for find maximum difference of T-score error which occurred operator ROI controlling. Standard deviation of T-score of B-test showed 0.1 higher then A-test in femur neck. Standard deviation of B-test showed 0.2 higher then A-test in Ward's area which in Greater trocanter and Inter trocanter. Standard deviation of B-test showed 0,1 lower then A-test in L-1. Bone density testing about Two hundred patients results are as follow. When operator ROI was changed wider than normal ROI, bone density of femur was measured more higher but bone density of L-spine was measured more lower then normal bone density. That means, sometime DEXA bone density testing result is dependent by operator ROI controlling. This is relevant with the patient's medicine and health insurance, thus, tester always keep the size of ROI for to prevent any problem in the patient.

Lee, Yun Hong [Dept. of Diagnostic Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of); Lee, In Ja [Dept. of Radiological Technology, Dongnam Health College, Suwon (Korea, Republic of); Yong, Hyung Jin [Dept. of Medicine Physics, The Graduate School of Biomedical Science Korea University, Seoul (Korea, Republic of)

2012-03-15

318

Analysis of trabecular bone architectural changes induced by osteoarthritis in rabbit femur using 3D active shape model and digital topology  

Science.gov (United States)

Osteoarthritis (OA) is the most common chronic joint disease, which causes the cartilage between the bone joints to wear away, leading to pain and stiffness. Currently, progression of OA is monitored by measuring joint space width using x-ray or cartilage volume using MRI. However, OA affects all periarticular tissues, including cartilage and bone. It has been shown previously that in animal models of OA, trabecular bone (TB) architecture is particularly affected. Furthermore, relative changes in architecture are dependent on the depth of the TB region with respect to the bone surface and main direction of load on the bone. The purpose of this study was to develop a new method for accurately evaluating 3D architectural changes induced by OA in TB. Determining the TB test domain that represents the same anatomic region across different animals is crucial for studying disease etiology, progression and response to therapy. It also represents a major technical challenge in analyzing architectural changes. Here, we solve this problem using a new active shape model (ASM)-based approach. A new and effective semi-automatic landmark selection approach has been developed for rabbit distal femur surface that can easily be adopted for many other anatomical regions. It has been observed that, on average, a trained operator can complete the user interaction part of landmark specification process in less than 15 minutes for each bone data set. Digital topological analysis and fuzzy distance transform derived parameters are used for quantifying TB architecture. The method has been applied on micro-CT data of excised rabbit femur joints from anterior cruciate ligament transected (ACLT) (n = 6) and sham (n = 9) operated groups collected at two and two-to-eight week post-surgery, respectively. An ASM of the rabbit right distal femur has been generated from the sham group micro-CT data. The results suggest that, in conjunction with ASM, digital topological parameters are suitable for analyzing architectural changes induced by OA.

Saha, P. K.; Rajapakse, C. S.; Williams, D. S.; Duong, L.; Coimbra, A.

2007-03-01

319

Intra-subject variability in human bone marrow stromal cell (BMSC) replicative senescence: molecular changes associated with BMSC senescence.  

Science.gov (United States)

The outcomes of clinical trials using bone marrow stromal cell (BMSC) are variable; the degree of the expansion of BMSCs during clinical manufacturing may contribute to this variability since cell expansion is limited by senescence. Human BMSCs from aspirates of healthy subjects were subcultured serially until cell growth stopped. Phenotype and functional measurements of BMSCs from two subjects including senescence-associated beta-galactosidase staining and colony formation efficiency changed from an early to a senescence pattern at passage 6 or 7. Transcriptome analysis of 10 early and 15 late passage BMSC samples from 5 subjects revealed 2122 differentially expressed genes, which were associated with immune response, development, and cell proliferation pathways. Analysis of 57 serial BMSC samples from 7 donors revealed that the change from an early to senescent profile was variable among subjects and occurred prior to changes in phenotypes. BMSC age expressed as a percentage of maximum population doublings (PDs) was a good indicator for an early or senescence transcription signature but this measure of BMSC life span can only be calculated after expanding BMSCs to senescence. In order to find a more useful surrogate measure of BMSC age, we used a computational biology approach to identify a set of genes whose expression at each passage would predict elapsed age of BMSCs. A total of 155 genes were highly correlated with BMSC age. A least angle regression algorithm identified a set of 24 BMSC age-predictive genes. In conclusion, the onset of senescence-associated molecular changes was variable and preceded changes in other indicators of BMSC quality and senescence. The 24 BMSC age predictive genes will be useful in assessing the quality of clinical BMSC products. PMID:23959330

Ren, Jiaqiang; Stroncek, David F; Zhao, Yingdong; Jin, Ping; Castiello, Luciano; Civini, Sara; Wang, Huan; Feng, Ji; Tran, Katherine; Kuznetsov, Sergei A; Robey, Pamela G; Sabatino, Marianna

2013-11-01

320

Age-related changes in the hemodynamics of the femoral head as evaluated by early phase of bone scintigraphy  

International Nuclear Information System (INIS)

The femoral head is reported to be in a markedly hypoemic state as compared with other tissues even under normal conditions, and it is therefore necessary to understand its hemodynamics to investigate the pathogenesis of hip disorders. It is known that aspects of intraosseous hemodynamics including blood flow and blood pool can be evaluated soon after radioisotope administration. In this study, hemodynamic changes in the femoral head according to gender and age were examined by investigating accumulation of radioisotope in the tissue during the early phase of bone scintigraphy. The subjects of this study consisted of 58 joints of 31 men and 75 joints of 41 women, whose ages ranged from 15 to 87 years (average age: 67.9 years). Images of bone scintigraphy were obtained for 15 to 20 minutes at 5 minutes and at 3 hours after radioisotope administration. The ratio of accumulation in the femoral head to that in the diaphysis (head-to-diaphysis ratio, HD ratio) was calculated. HD ratios obtained 15-20 minutes later ranged from 0.01 to 7.35 (1.88±0.91, mean±SD). HD ratios decreased with age, and a significant inverse correlation was observed between age and HD ratio, demonstrating a correlation coefficient of -0.27 (p=0.001). The HD ratio among men was 0.01-3.57 (1.66±0.71), while that among women was 0.53-7.35 (2.05±1.01), and a significant difference was observed in HD ratio between men and women (p=0.02). There was a significant difference in HD ratios between men andifference in HD ratios between men and women in their teens to forties (p=0.03), while no significant differences was observed in the other age groups. HD ratios obtained 3 hours later ranged from 0.44 to 6.32 (1.95±0.79, mean±SD), and no significant correlation was observed between age and HD ratio, demonstrating a correlation coefficient of -0.14. The present study demonstrated that blood flow and blood pool of the femoral head decrease with aging particularly in women. This hemodynamic deterioration of the femoral head caused by aging may have an effect on the onset and progression of hip disorders by influencing bone metabolism. (author)

 
 
 
 
321

Cytogenetic changes in bone marrow and fibroblast cells of BALB/C laboratory mice induced by Mestranol  

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Full Text Available In this work the genotoxic effects provoked by Mestranol, which belongs to the group of chemical rodenticide-chemosterilants, were examined as a function of dose (7,5, 15 and 30 mg/kg w.b./c.c and of time (10, 20 and 30 days or 3, 5 and 7 days for "in vivo" and "in vitro" conditions respectively. The genotoxic effects were scored on the basis of numerical and structural aberrations in both bone marrow and fibroblast cells from BALB/C laboratory mice in comparison to control groups. Increased doses of the preparation increased numerical aberrations in both bone marrow and fibroblast cells significantly (p<0.01 so that the greatest changes were noticed after the treatment with 30 mg/kg w.b./c.c. Numerical aberrations showed no significant differences (p<0.05 as a function of time. Also, the several times greater number of aneuploid cells was significantly different (p<0.01 compared to the number of polyploid cells Greater values for structural aberrations were obtained not only after the treatment with the largest dose of 30 mg/kg w.b./c.c., but also after longer exposure times (i.e. for 30 or 5 days respectively. Statistically significant differences were found between the number of gaps, as well as fragments, in comparasion to the number of Robertsonian translocations (p<0.01, while there were no significant differences between the number of gaps and fragments (p>0.05.

Teodorovi? Radislava

2004-01-01

322

Rate of blunt impact loading affects changes in retropatellar cartilage and underlying bone in the rabbit patella.  

Science.gov (United States)

Our laboratory has developed a small animal model using Giant Flemish rabbits to examine chronic degradative changes in joint tissues following a blunt impact. Historically, we observe surface fissuring and decreases in the elastic modulus of retropatellar cartilage along with thickening of the underlying subchondral bone. Previous studies resulted in load insults that peaked in approximately 5ms, while loads that occur during automotive accidents or heavy exercise can produce longer rise times. The objective of the current study was to examine the influence of blunt impact loading rate using our established model. We hypothesized that the extent of fissuring and softening of retropatellar cartilage following impact would not be significantly different for a high (5ms to peak) versus low (50ms to peak) rate of loading experiment. Eight animals were impacted with a high rate of loading blunt impact, while ten animals were subjected to the same impact load at a low rate of loading. An additional eight animals served as a control population. All animals were sacrificed 12 months post-impact. The study yielded unexpected results for the first hypothesis. The high rate of loading experiments generated more surface fissuring of the retropatellar cartilage than the low rate of loading experiments. However, the degree of softening was similar for the two rates, which supported the second hypothesis. Furthermore, the study documented more thickening of bone underlying retropatellar cartilage following the high versus the low rate of loading experiments. The current study suggested that chronic injury mechanisms may be highly dependent on the rate of impact loading. These data could become extremely relevant in the development of high-velocity "safety" devices, such as knee air bags, that are needed to help position an unbelted occupant in an automobile crash. PMID:12020994

Ewers, B J; Jayaraman, V M; Banglmaier, R F; Haut, Roger C

2002-06-01

323

The role of heating, cavitation and acoustic streaming in mediating ultrasound-induced changes of TGF-? gene expression in bone cells  

International Nuclear Information System (INIS)

This paper relates ultrasound-induced changes in bone cell function to quantitative data assessing the level of several interaction mechanisms within the exposure environment. Characterisation of ultrasound fields in terms of resultant levels of heating, cavitation and acoustic streaming may provide a novel means of accurately assessing the likelihood of biological effects in vitro

324

The role of heating, cavitation and acoustic streaming in mediating ultrasound-induced changes of TGF-beta gene expression in bone cells  

Science.gov (United States)

This paper relates ultrasound-induced changes in bone cell function to quantitative data assessing the level of several interaction mechanisms within the exposure environment. Characterisation of ultrasound fields in terms of resultant levels of heating, cavitation and acoustic streaming may provide a novel means of accurately assessing the likelihood of biological effects in vitro.

Harle, J.; Mayia, F.

2004-01-01

325

Bone Markers  

Science.gov (United States)

... of this website will be limited. Search Help? Bone Markers Share this page: Was this page helpful? ... decrease bone marker results? 1. Should everyone have bone marker testing performed? Bone marker testing is typically ...

326

Changes in 3-dimensional bone structure indices in hypoparathyroid patients treated with PTH(1-84) : A randomized controlled study  

DEFF Research Database (Denmark)

Hypoparathyroidism (hypoPT) is characterized by a state of low bone turnover and high bone mineral density (BMD) despite conventional treatment with calcium supplements and active vitamin D analogues. To assess effects of PTH substitution therapy on 3-dimensional bone structure, we randomized 62 patients with hypoPT into 24 weeks of treatment with either PTH(1-84) 100?µg/day subcutaneously or similar placebo as an add-on therapy. Micro-computed tomography was performed on 44 iliac crest bone biopsies (23 on PTH treatment) obtained after 24 weeks of treatment. Compared with placebo, PTH caused a 27% lower trabecular thickness (p?

Sikjaer, Tanja; Rejnmark, Lars

2012-01-01

327

Changes in the linear attenuation coefficient of canine appendicular bone following intravenous infusion of strontium lactate, measured using gamma-ray computed tomography.  

Science.gov (United States)

Changes in the average linear attenuation coefficient (LAC) within a fixed measurement volume in the proximal end of the dog tibia, which contains trabecular bone and associated soft tissues (the trabecular bone "space"), were monitored continuously using gamma-ray computed tomography (gamma-CT) prior to, during, and following intravenous infusion of strontium (Sr) lactate. An infusion of 1.3-4.7 g of Sr over a period of 110-160 minutes into 20-kg dogs resulted, within 6-8 hours, in an increase of 0.019-0.045 cm-1 (P less than 0.002) in the LAC. Calibration of the gamma-CT system showed that 0.44 mg/cm3 of Sr produced a change of 0.01 cm-1 in the LAC. Using this conversion factor, the Sr concentration in the trabecular bone space resulting from infusion, as measured by flame atomic absorption spectroscopy, agreed with that predicted by the change observed in the LAC. Sr present in the serum and urine was consistent with the changes observed in the LAC over the study period. Control dogs infused with mineral-free solutions showed no change in LAC. Calcium equivalents required to give the changes observed in the LAC using Sr indicate that variations in skeletal turnover in man can be monitored in the peripheral skeleton using gamma-CT. PMID:1571847

Overton, T R; Snyder, R E; Hangartner, T N; Girgis, S; Audette, R J; Secord, D C

1992-04-01

328

Mouse bone marrow-derived mast cells (BMMC) change their phenotype when cultured with fibroblasts  

International Nuclear Information System (INIS)

The heparin-containing mast cells (HP-MC) that reside in the connective tissues of the mouse, but not the chondroitin sulfate containing mast cells in the gastrointestinal mucosa, stain with safranin when exposed to alcian blue/safranin. Mouse BMMC (the presumptive in vitro counterpart of the in vivo differentiated mucosal mast cell) were cultured for 2-14 days with confluent skin-derived 3T3 fibroblasts in RPMI-1640 containing 10% fetal calf serum and 50% WEHI-3 conditioned medium. Although the BMMC adhered to the fibroblast monolayer, they continued to divide, probably due to the presence of interleukin-3 in the conditioned medium. The mast cells remained viable throughout the period of co-culture, since they failed to release LDG and because they increased their histamine content per cell ?15-fold. After 8-9 days of co-culture, >50% of the BMMC changed histochemically becoming safranin positive. At this time, 30-50% of the [35S]glycosaminoglycans on the proteoglycans synthesized by these co-cultured mass cells were heparin, whereas the initial BMMC synthesized proteoglycans containing only chondroitin sulfate E. That interleukin 3-dependent mouse BMMC can be induced to undergo a phenotypic change so as to express characteristics of a HP-MC suggests that the tissue microenvironment determines the differentiated characteristics of these cells

329

System Re-set: High LET Radiation or Transient Musculoskeletal Disuse Cause Lasting Changes in Oxidative Defense Pathways Within Bone  

Science.gov (United States)

Six months post-IR, there were no notable changes in skeletal expression of 84 principal genes in the p53 signaling pathway due to low dose IR (0.5Gy), HU, or both. In contrast, numerous genes relevant to oxidative stress were regulated by the treatments, typically in a direction indicative of increased oxidative stress and impaired defense. IR and HU independently reduced (between 0.46 to 0.88 fold) expression levels of Noxa1, Gpx3, Prdx2, Prdx3, and Zmynd17. Surprisingly, transient HU alone (sham-irradiated) decreased expression of several redox-related genes (Gpx1,Gstk1, Prdx1, Txnrd2), which were not affected significantly by IR alone. Irradiation increased (1.13 fold) expression of a gene responsible for production of superoxides by neutrophils (NCF2). Of interest, only combined treatment with HU and IR led to increased expression levels of Ercc2, (1.19 fold), a DNA excision repair enzyme. Differences in gene expression levels may reflect a change in gene expression on a per cell basis, a shift in the repertoire of specific cell types within the tissue, or both. Serum nitrite/nitrate levels were elevated to comparable levels (1.6-fold) due to IR, HU or both, indicative of elevated systemic nitrosyl stress. CONCLUSIONS The magnitude of changes in skeletal expression of oxidative stress-related genes six months after irradiation and/or transient unloading tended to be relatively modest (0.46-1.15 fold), whereas the p53 pathway was not affected. The finding that many different oxidative stress-related genes differed from controls at this late time point implicates a generalized impairment of oxidative defense within skeletal tissue, which coincides with both profound radiation damage to osteoprogenitors/stem cells in bone marrow and impaired remodeling of mineralized tissue.

Kumar, Akhilesh; Chatterjee, A.; Alwood, Joshua S.; Dvorochkin, Natalya; Almeida, Eduardo A. C.

2011-01-01

330

Effects of broiler breeder-feeding programme and feeder space change at photostimulation using maize- or wheat-based diets on eggshell properties and progeny bone development.  

Science.gov (United States)

1. The effects of diet type, feeding programme and fast- or slow-feed allocation in fast-feathering Cobb 500 broiler breeder hens on eggshell properties and broiler progeny bone development were investigated in a 2 × 2 × 2 factorial experiment. 2. The birds were fed on either maize- or wheat-based diets during rearing and production and on a fast- or slow-feed allocation programme from 14 to 29 weeks of age. At 22 weeks, 69 females from each pen were placed in a layer house where feeder space (FS) either remained similar or was increased. 3. Eggs produced at 33 weeks were incubated, eggshell conductance (G) was determined and a sample of 14 chicks from each treatment combination was taken to obtain bone traits at hatching. 4. Diet type did not influence G, yolk-free body weight (BW), residual yolk weight or relative asymmetry (RA) of any bilateral traits of leg bones of hatchlings. However, breeder diet type was involved on two-way and three-way interaction effects on progeny leg bone traits. 5. Breeders feed restricted according to the slow-feeding programme laid eggs with greater G compared to those managed with the fast-feeding programme, but there was no effect of feeding programme on progeny bone traits at hatching. 6. Eggs from breeders given more FS at photostimulation had greater G than those from breeders provided with similar FS. Maternal FS change did not influence hatchling yolk-free BW; however, breeders given more FS produced progeny with heavier tibias and shanks and longer femurs compared with those provided with similar FS, but only when breeders were fed on maize. Moreover, increased maternal FS at photostimulation was associated with an increased RA of femur length in the progeny. 7. It was concluded that breeder FS change at photostimulation influenced eggshell conductance and consistently affected bone development of the broiler progeny. PMID:24814245

Eusebio-Balcazar, P; Oviedo-Rondón, E O; Wineland, M J; Pérez Serrano, M; Brake, J

2014-01-01

331

Reactive mesenchymal proliferation.  

Science.gov (United States)

One hundred and thirteen cases in the files of the Netherlands Committee on Bone Tumors were diagnosed as heterotopic soft tissue ossification. Myositis ossificans was diagnosed in 62, ossifying hematoma in 21, and pseudomalignant osseous tumor of soft tissues in 30 cases. Antecedent trauma was present in 37%, 46% and 7%, respectively. Myositis ossificans arose in the large muscle groups of the thighs and upper arms; when closely related to the shaft of a bone, periosteal reactions were more outspoken. Pseudomalignant osseous tumor of soft tissues was located in the hands, feet, and pelvis, some cases were not in muscle groups and some were almost periosteal. Ossifying hematoma was located in the upper and lower legs and usually in close relation to bone. The three entities belong to the same kind of reactive mesenchymal proliferative process. The radiologic and histologic patterns are reflections of whether the lesions are closely localized to bone shafts or in soft tissues, e.g. in muscles and therefore the term "reactive mesenchymal proliferation" is preferred to myositis ossificans, pseudomalignant osseous tumor of soft tissues and ossifying hematoma. Diagnostic problems are encountered in early phases when cellularity, mitotic activity, and infiltrative spread suggest malignancy. Recognition of these reactions in early phases is important to avoid mutilating surgery. PMID:1459931

Schütte, H E; van der Heul, R O

1992-08-01

332

Effect of changes of serum IGF-II and CT contents on bone metabolism in healthy subjects  

International Nuclear Information System (INIS)

Objective: To explore the effect of changes of serum insulin like growth factor II (IGF-II) and calcitonin (CT) on bone metabolism in both male and female healthy subjects of different age groups. Methods: Serum IGF-II and CT contents were determined with RIA in 180 healthy subjects of both sexes in 5 age groups (27-39, 40-49, 50-59, 60-69 and over 70). Results: The serum contents of IGF-II and CT decreased gradually as the age increased. The IGF-II contents in subjects above 70 were significantly lower than those in all other subjects (P<0.01); the values in subjects of the age group 27-39 were also significantly higher than those in the 60-69 group (P<0.05). Again, the serum CT contents in subjects over 50 were significantly lower than those in subjects below 50 (P<0.05, P<0.01). There were little differences among the levels in both sexes, with the exception of a slight but not significant lower value in the females above 50. Conclusion: In older subjects, the decreased contents of serum IGF-II would exert less modulation on osteoblastic activity while the decreased contents of CT would exert less inhibition on osteolytic activity. The contents in older females were even lower due to the decreased estrogen level. Combination of these two factors would lead to the initiation and development of osteoporosis. (authors)

333

In vivo dynamic loading reduces bone growth without histomorphometric changes of the growth plate.  

Science.gov (United States)

This in vivo study aimed at investigating the effects of dynamic compression on the growth plate. Rats (28 days old) were divided into three dynamically loaded groups, compared with two groups (control, sham). A device was implanted on the 6th and 8th caudal vertebrae for 15 days. Controls (n = 4) did not undergo surgery. Shams (n = 4) were operated but not loaded. Dynamic groups had sinusoidal compression with a mean value of 0.2 MPa: 1.0 Hz and ± 0.06 MPa (group a, n = 4); 0.1 Hz and ± 0.2 MPa (group b, n = 4); 1.0 Hz and ± 0.14 MPa (group c, n = 3). Growth rates (µm/day) of dynamic groups (a) and (b) were lower than shams (p 0.01). Rats from dynamic group (c) had repeated inflammations damaging tissues; consequently, their analysis was unachievable. Increasing magnitude or frequency leads to growth reduction without histomorphometric changes. However, the combined augmentation of magnitude and frequency alter drastically growth plate integrity. Appropriate loading parameters could be leveraged for developing novel growth modulation implants to treat skeletal deformities. PMID:24902946

Ménard, Anne-Laure; Grimard, Guy; Valteau, Barthélémy; Londono, Irène; Moldovan, Florina; Villemure, Isabelle

2014-09-01

334

1. modification of the proliferative capacity of transplanted bone marrow colony forming units by changes in the host environment  

International Nuclear Information System (INIS)

Regulation of the proliferation of transplanted colony forming units (CFUs) was investigated in lethally irradiated mice, pretreated by methods known to accelerate hemopoietic recovery after sublethal irradiation. Prospective recipients were exposed to either hypoxia, vinblastine or priming irradiation and at different intervals thereafter lethally irradiated and transplanted with bone marrow. Repopulation of CFUs was determined by counting the number of splenic colonies in primary recipients or by retransplantation. Regeneration of grafted CFUs was greatly accelerated and their self-renewal capacity increased in mice grafted within 2 days after hypoxia. Also the number of splenic colonies formed by grafted syngeneic CFUs as well as by C57B1 parent CFUs growing in BC3F1 hosts was significantly increased. The effect was not dependent on the seeding efficiency of CFUs and apparently resulted from hypoxia induced changes in the hosts' physiological environment. Proliferative capacity of grafted CFUs increased remarkably in hosts receiving vinblastine 2 or 4 days prior to irradiation. Priming irradiation given 6 days before main irradiation accelerated, given 2 days before impaired regeneration of CFUs. The increased rate of regeneration was not related to the cellularity of hemopoietic organs at the time of transplantation. The growth of CFUs in diffusion chambers implanted into posthypoxic mice was only slightly improved which does indicate that the accelerated regeneration of CFUs in posthypoxic mice is mainly due to the changes in the hemopoietic microenvironment. A short conditioning of transplanted CFUs by host factor(s) was sufficient to improve regeneration. The results might suggest that the speed of hemopoietic regeneration depends on the number of CFUs being induced to proliferate shortly after irradiation, rather than on the absolute numbers of CFUs available to the organism. (author)

335

Bone marrow edema of the knee joint  

International Nuclear Information System (INIS)

Bone marrow edema of the knee joint is a frequent clinical picture in MR diagnostics. It can be accompanied by symptoms and pain in the joint. Diseases that are associated with bone marrow edema can be classified into different groups. Group 1 includes vascular ischemic bone marrow edema with osteonecrosis (synonyms: SONK or Ahlbaeck's disease), osteochondrosis dissecans, and bone marrow edema syndrome. Group 2 comprises traumatic or mechanical bone marrow edema. Group 3 encompasses reactive bone marrow edemas such as those occurring in gonarthrosis, postoperative bone marrow edemas, and reactive edemas in tumors or tumorlike diseases. Evidence for bone marrow edema is effectively provided by MRI, but purely morphological MR information is often unspecific so that anamnestic and clinical details are necessary in most cases for definitive disease classification. (orig.)

336

Bone Anchored Hearing Treatment Procedure  

Medline Plus

Full Text Available ... transmitted very efficiently through the head using bone conduction. The Baha device uses sound vibrations, and those ... changed from a normal soundwave into a bone conduction vibration, and that is what is passed then ...

337

Photodynamic therapy of diseased bone  

Science.gov (United States)

Objective: Photodynamic therapy (PDT) defines the oxygen-dependent reaction that occurs upon light-mediated activation of a photosensitizing compound, culminating in the generation of cytotoxic, reactive oxygen species, predominantly, singlet oxygen. We are investigating PDT treatment of diseased bone. Methods: Using a rat model of human breast cancer (MT-1)-derived bone metastasis we confirmed the efficacy of benzoporphyrin-derivative monoacid (BPD-MA)-PDT for treating metastatic lesions within vertebrae or long bones. Results: Light administration (150 J) 15 mins after BPDMA (2.5 mg/Kg, i.v.) into the lumbar (L3) vertebra of rats resulted in complete ablation of the tumour and surrounding bone marrow 48 hrs post-PDT without paralysis. Porcine vertebrae provided a model comparable to that of human for light propagation (at 150 J/cm) and PDT response (BPD-MA; 6 mg/m2, i.v.) in non-tumour vertebrae. Precise fibre placement was afforded by 3-D cone beam computed tomography. Average penetration depth of light was 0.16 +/- 0.04 cm, however, the necrotic/non-necrotic interface extended 0.6 cm out from the treatment fiber with an average incident fluence rate of 4.3 mW/cm2. Non-necrotic tissue damage was evident 2 cm out from the treatment fiber. Current studies involving BPD-MA-PDT treatment of primary osteosarcomas in the forelimbs of dogs are very promising. Magnetic resonance imaging 24 hr post treatment reveal well circumscribed margins of treatment that encompass the entire 3-4 cm lesion. Finally, we are also interested in using 5-aminolevulinic acid (ALA) mediated PDT to treat osteomyelitis. Response to therapy was monitored as changes in bioluminescence signal of staphylococcus aureus (SA)-derived biofilms grown onto 0.5 cm lengths of wire and subjected to ALA-PDT either in vitro or in vivo upon implant into the intramedullary space of rat tibia. Transcutaneous delivery of PDT (75 J/cm2) effectively eradicated SAbiofilms within bone. Conclusions: Results support the application of PDT to the treatment of primary or metastatic lesions within bone. Secondly, that ALA-PDT may be useful as a treatment for osteomyelitis. Further studies aim to optimize the parameters of delivering PDT into bone and explore imaging technologies that can be used for clinical PDT.

Bisland, Stuart K.; Yee, Albert; Siewerdsen, Jeffery; Wilson, Brian C.; Burch, Shane

2005-08-01

338

Effect of antioxidants on thiobarbituric acid reactive substances of mechanically de boned chicken meat irradiated with ionizing radiation: cobalt-60 and electron beam sources  

International Nuclear Information System (INIS)

Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 - A1 (0.3% Sodium Polyphosphate and Sodium Erythorbate 0.05%) and Antioxidant 2 - A2 (Rosemary Extract 0.02% and ?-Tocopherol 0.01%). The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (Cn/I), with antioxidant A1 and non-irradiated (A1n/I), with antioxidant A2 and non-irradiated (A2n/I) without antioxidant and irradiated in Cobalt-60 source (CCo), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). Each 100 g sample was conditioned in a transparent, low density polyethylene oxygen permeable bag, frozen overnight at a temperature of -18 +- 1 deg C in a chamber, and irradiated in this state, maintaining the temperature low with dry ice. The samples were irradiated with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy.h-1) and electron beam (2.9 kGy.s-1). After this process, the samples were evaluated during the refrigeration period (2 +- 1 deg C) for 11 days for the following analysis: total psychotropic bacteria count, thiobarbituric acid reactive substances (TBARS). The addition of antioxidants was able to reduce lipid oxidation caused by the irradiation. There were no differences between the radiation sources used in the same parameters. The better antioxidants mixture in the TBARS reducing it was rosemary extract and ?-tocopherol (A2). (author)

339

Effect of antioxidants on thiobarbituric acid reactive substances of mechanically de boned chicken meat irradiated with ionizing radiation: cobalt-60 and electron beam sources  

Energy Technology Data Exchange (ETDEWEB)

Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 - A1 (0.3% Sodium Polyphosphate and Sodium Erythorbate 0.05%) and Antioxidant 2 - A2 (Rosemary Extract 0.02% and {alpha}-Tocopherol 0.01%). The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (Cn/I), with antioxidant A1 and non-irradiated (A1n/I), with antioxidant A2 and non-irradiated (A2n/I) without antioxidant and irradiated in Cobalt-60 source (CCo), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). Each 100 g sample was conditioned in a transparent, low density polyethylene oxygen permeable bag, frozen overnight at a temperature of -18 +- 1 deg C in a chamber, and irradiated in this state, maintaining the temperature low with dry ice. The samples were irradiated with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy.h{sup -1}) and electron beam (2.9 kGy.s{sup -1}). After this process, the samples were evaluated during the refrigeration period (2 +- 1 deg C) for 11 days for the following analysis: total psychotropic bacteria count, thiobarbituric acid reactive substances (TBARS). The addition of antioxidants was able to reduce lipid oxidation caused by the irradiation. There were no differences between the radiation sources used in the same parameters. The better antioxidants mixture in the TBARS reducing it was rosemary extract and {alpha}-tocopherol (A2). (author)

Brito, Poliana de Paula; Azevedo, Heliana de; Pomarico Neto, Walter; Roque, Claudio Vitor; Brusqui, Armando Luiz, E-mail: hgomes@cnen.gov.b, E-mail: pbrito@cnen.gov.b, E-mail: cvroque@cnen.gov.b, E-mail: abrusqui@cnen.gov.b [Brazilian Nuclear Energy Commission (LAPOC/CNEN), Pocos de Caldas, MG (Brazil); Haguiwara, Marcia Mayumi Harada; Miyagusku, Luciana, E-mail: marciamh@ital.gov.b, E-mail: lucianam@ital.gov.b [Food Technology Institute (ITAL), SP (Brazil). Meat Technology Center

2011-07-01

340

Changes in T1 relaxation processes in the bone marrow following treatment in children with acute lymphoblastic leukemia  

International Nuclear Information System (INIS)

Magnetic resonance imaging (MRI) and T1 relaxation time measurements of the vertebral bone marrow were performed in 11 children with acute lymphoblastic leukemia (ALL) at diagnosis. Nine of the children were re-examined after chemotherapeutic treatment. The results were compared with histological data from bone marrow biopsies obtained in close association to the MR examinations. Ten age matched children were examined as a control group. A 1.5 Tesla whole body scanner was used for the measurements. The pretreatment T1 relaxation times of the bone marrow were significantly prolonged, compared to the age matched controls. After chemotherapy the T1 relaxation times of the children with ALL decreased significantly towards or into the normal range. A significant correlation was found between the T1 relaxation time and the content of malignant blast cells in the bone marrow. (orig.)

 
 
 
 
341

Teriparatide vs. Alendronate as a treatment for osteoporosis: Changes in biochemical markers of bone turnover, BMD and quality of life  

Science.gov (United States)

Summary Background We studied the use of teriparatide in postmenopausal women with severe osteoporosis. Material/Methods Two groups (A and B) of patients affected by severe osteoporosis (T-score ??2.5 at bone mineral density were analyzed and 2 vertebral fractures on radiograph). Group A was treated for 18 months with 20 ?g/day of teriparatide. Group B was treated with bisphosphonates 70 mg/week. Every woman assumed 1 g of calcium and 800 IU of vitamin D3 daily. We evaluated the effects of therapy after 18 months (T18) from the beginning with bone turnover markers (alkaline phosphatase, procollagen type 1 N-terminal propeptide, and N-telopeptide cross-links) and dual-energy X-ray absorptiometry. Results Group A, at T18 procollagen type 1 N-terminal propeptide levels, increased 127%; bone alkaline phosphatase levels increased to 65%; N-telopeptide cross-links levels increased to 110%. Group B, at T18 procollagen type 1 N-terminal propeptide levels, decreased to 74%; bone alkaline phosphatase levels decreased to 41%; N-telopeptide cross-links levels decreased to 72%. After 18 months, lumbar bone mineral density increased to 12.4% and femoral bone mineral density increased to 5.2% in group A. Group B lumbar bone mineral density increased to 3.85% and femoral bone mineral density increased to 1.99%. Only a new vertebral fracture occurred in group A (2.4%), whereas 6 fractures occurred in group B (15.7%). The quality of life questionnaire of the European Foundation for Osteoporosis (QUALEFFO) revealed a significant improvement in daily living, performed domestic jobs, and locomotor function in groups A and B. Conclusions The use of rhPTH in patients with severe osteoporosis offers more protection against fractures and improves the QoL more than bisphosphonates. PMID:21804463

Panico, Annalisa; Lupoli, Gelsy Arianna; Marciello, Francesca; Lupoli, Roberta; Cacciapuoti, Marianna; Martinelli, Addolorata; Granieri, Luciana; Iacono, Daniela; Lupoli, Giovanni

2011-01-01

342

MRI findings of bone tumor  

Energy Technology Data Exchange (ETDEWEB)

To investigate the usefulness of magnetic resonance imaging, MRI, of bone tumors, we retrospectively reviewed 32 MRI examination already diagnosed pathologically. Subjects included 18 males and 14 females, ranging in age from 5 to 63 years, with a means of 29.3 years. These included 25 benign bone tumors and 7 malignant bone tumors. The accuracy of a qualitative diagnosis was observed in giant cell tumor, osteoid osteoma, fibrous dysplasia and ossifying fibroma. In malignant bone tumors, it is difficult to accurately diagnose with MRI, although MRI was useful in showing interaction of the tumor and host tissue, extension, edema and reactive zone. (author)

Hamanaka, Hideaki; Kashiwagi, Teruyuki; Chosa, Etuo; Kuwahara, Shigeru; Tajima, Naoya [Miyazaki Medical Coll., Kiyotake (Japan)

1996-09-01

343

Bone Cancer  

Science.gov (United States)

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 ...

344

Bone Diseases  

Science.gov (United States)

Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly ... childhood and your teens, your body adds new bone faster than it removes old bone. After about ...

345

Calculations of Changes in Reactivity during some regular periods of operation of JEN-1 MOD Reactor; Calculo de vairaciones de reactividad en algunos periodos regulares de operacion del reactor JEN-1 Mod.  

Energy Technology Data Exchange (ETDEWEB)

By a Point-Reactor model and Perturbation Theory, changes in reactivity during some regular operating periods of JEN-1 MOD Reactor have been calculated and compared with available measured values. they were in good agreement. Also changes in reactivity have been calculated during operations at higher power levels than the present one, concluding some practical consequences for the case of increasing the present power of this reactor. (Author)

Alcala Ruiz, F.

1973-07-01

346

Bone Densitometry (Bone Density Scan)  

Science.gov (United States)

• Overview Bone density scanning, also called dual-energy x-ray absorptiometry (DXA) or bone densitometry , is an enhanced form of x-ray technology that is used to measure bone loss. DXA is today's established standard for measuring ...

347

Bone Mass Measurement (Bone Density)  

Science.gov (United States)

... service covered? Search Medicare.gov for covered items Bone mass measurement (bone density) How often is it covered? Medicare Part ... see if you're at risk to broken bones, once every 24 months (more often if medically ...

348

Prescriptive proprioceptive insoles and dental orthotics change the frontal plane position of the atlas (C1), mastoid, malar, temporal, and sphenoid bones: a preliminary study.  

Science.gov (United States)

The purpose of this series of case studies was to determine if the frontal plane position of the cranial bones and atlas could be altered using dental orthotics, prescriptive insoles, or both concurrently. The cranial radiographs of four patients were reviewed for the study. Three of the patients were diagnosed as having a temporomandibular joint (TMJ) dysfunction and a preclinical clubfoot deformity. The fourth patient was diagnosed as having a TMJ dysfunction, a preclinical clubfoot deformity and a Catetgory II sacral occipital subluxation, as designated in the chiropractic's Sacro Occipital Technique (SOT). Each patient had a series of four cranial radiographs taken using a modified orthogonal protocol. In two patients, improvement towards orthogonal was achieved when using both prescriptive dental orthotics and prescriptive insoles concurrently. Improvement towards orthogonal was less apparent when using only the prescriptive dental orthotic. No improvement or a negative frontal plane shift was noted when using only the prescriptive proprioceptive insoles. In the third patient, the frontal plane position of the cranial bones and atlas increased (away from orthogonal) when using the generic proprioceptive insoles alone or in combination with a prescriptive dental orthotic. In the fourth patient, the frontal plane position of the cranial bones improved using the dental orthotic. However, the proprioceptive insoles, when used alone or in combination with the dental orthotic, increased the frontal plane position of the cranial bones and atlas. This study demonstrates that changes in the frontal plane position of the cranial and atlas bones can occur when using proprioceptive insoles and/or dental orthotics. PMID:24308104

Rothbart, Brian A

2013-10-01

349

2D/3D Quantification of bone morphometric parameter changes using X-ray microtomograpphy with different pixel sizes  

Science.gov (United States)

In recent years, bone quantification led to a deeper knowledge of the 3D microarchitecture. In this study the bone architecture of rats was investigated based on 2D/3D morphometric analysis using microcomputed tomography, aiming at determining the effect of the image acquisition pixel on the quality of some 2D/3D morphometric parameters, such as porosity and trabecular density.Six pairs of bone samples were used and the scans were carried out using high microcomputed tomography system, operating at three different pixel sizes of 33.3 ?m, 15.0 ?m and 9.5 ?m. The results showed 2D parameters values lower than those obtained in the 3D analysis, mainly for trabecular density, separation and thickness.

Vidal, F.; de Assis, J. T.; Lopes, R. T.; Lima, I.

2014-02-01

350

Changes of cell-vascular complex in zones of adaptive remodeling of the bone tissue under microgravity conditions  

Science.gov (United States)

We examined the peculiarities of the structure of the blood-vascular bed and perivascular cells in zones of osteogenesis in the epiphyses and metaphises of femoral bones of rats, flown aboard the US laboratory SLS-2 for two weeks by electron microscopy and histochemistry. In zones of bone remodeling, there was a tendency for a reduction of sinusoid capillary specific volume. Endotheliocytes preserve the typical structure. In the population of perivascular cells, we discovered differentiating osteogenic cells that contained alkaline phosphomonoesterase as well as cells that don't contain this enzyme and differentiate into fibroblasts. The fibroblasts genesis in zones of adaptive remodeling of spongy bones leads to a further development of fibrous tissue that is not subject to mineralization.

Rodionova, N. V.; Oganov, V. S.

2003-10-01

351

Incidence and clinical importance of chronic reactive periostal new formations of bone in the cervical region in patients with varying neurological symptomatology  

International Nuclear Information System (INIS)

81 patients classed into three groups with clinical evidence of neurological symptoms and posttraumatic pain of the cervical spine and the incidence of degenerative disorders were studied noninvasively via CT scanning. In about half of the patients with nerve-root symptomatology as well as with signs of involvement of long tracts, narrowing of the foramen intervertebrale, respectively of the spinal tract, was seen, attributable to degenerative osseous apposition with excellent clinical segmental and (according to radicular symptoms) side correlation. In contrast to these results the group of patients with posttraumatic clinical symptoms showed almost 50% less preexisting degenerative disorders of the cervical spine. Hypertrophic changes of the processus articulares with narrowing of the spinal canal occurred in 14% and were therefore of minor clinical significance. (orig./GDG)

352

Reactive Arthritis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Reactive arthritis is an acute, sterile, non-suppurative and inflammatory arthropaty which has occured as a result of an infectious processes, mostly after gastrointestinal and genitourinary tract infections. Reiter syndrome is a frequent type of reactive arthritis. Both reactive arthritis and Reiter syndrome belong to the group of seronegative spondyloarthropathies, associated with HLA-B27 positivity and characterized by ongoing inflammation after an infectious episode. The classical triad o...

Eren Erken; Didem Arslan Tas; Fatih Yildiz

2013-01-01

353

Bone demineralization  

Science.gov (United States)

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.

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

1971-01-01

354

Development of the maxillo-mandibular first molars and developmental changes in the alveolar bone morphology. Three-dimensional observation by X-ray CT  

International Nuclear Information System (INIS)

To investigate the development of the maxillo-mandibular first molars and accompanying developmental changes in the alveolar bone morphology during the period from the intra-jaw bone stage to the completion stage of tooth eruption, dry skulls were three-dimensionally observed using X-ray CT. The specimens were 34 dry skulls composed of 17 skulls in the deciduous dentition period (dental age IIA) and 17 skulls in the first half of the mixed dentition period (dental age IIC, IIIA). The following results were obtained: By observing the horizontally sectioned images, the maxillary first molars approached the area on the deciduous dentition line from the palatal side, during the period from the deciduous dentition period to the first half of the mixed dentition period. The mandibular first molars approached the area on the deciduous dentition line from the buccal side. By observing the vertically sectioned images, development of the maxillary alveolar bone was higher than that of the mandibular alveolar bone during the period from the deciduous dentition period to the first half of the mixed dentition period. Although differences in the development of the alveolar bone between the maxilla and mandible were noted in the deciduous dentition period, the size of the maxilla was similar to that of the mandible in the first half of the mixed dentition period. Furthermore, positional changes in the buccal direction were marked in the maxillary first molars, which were located on llary first molars, which were located on the buccal side of the mandibular teeth in the first half of the mixed dentition period. Observation of the vertically sectioned images also showed that the inclination angle of the coronal axis of the first molars was large in both the maxilla and mandible in the first half of the mixed dentition period, which was marked in the mandible in particular. These results showed that in the first half of the mixed dentition period, in which the early occlusion of the first molars is established, development of the maxillo-mandibular alveolar bones gradually becomes harmonized, and occlusion occurs by the inclination of the maxillo-mandibular tooth axis. (author)

355

Analogue-digital conversion in order to evaluate long-term changes in uptake of isotopes in bone scintigraphy of secondary hyperparathyroidism  

International Nuclear Information System (INIS)

An analogue-digital conversion was developed, thereby allowing the incorporation of whole-body bone scintigrams, obtained by a gamma camera, into digital data via the video camera and then allowing the processing of the incorporated digital data. Using the new method, 18 hemodialysis patients, who were voluntarily selected from those who had undergone bone scintigraphy with 99mTc-HMDP for secondary hyperparathyroidism, were examined to determine serial changes in tracer uptake. The mean duration of hemodialysis was 6. 3 years (immediately up to 25.2 years). The tracer count ratio of the central part of the skull to the lower part of the sternum correlated most well with C-PTH. The analogue-digital conversion was found to yield a slightly higher value for the above-mentioned ratio than the original data; however, there was a good correlation between the analogue-digital conversion and original data. (N.K.)

356

Bone health in adolescence  

Directory of Open Access Journals (Sweden)

Full Text Available The skeleton undergoes rapid change with respect to growth, modeling and remodeling processes in adolescence. Consequently, the effects of factors that affect bone health positively or negatively can be greater. Between 40% and 60% of, peak bone mass which serves as the bone bank for life, is accrued during adolescence. Lifetime risk of osteoporosis and fracture may be increased if optimal peak bone mass cannot be reached.Accrual of peak bone mass is affected by unmodifiable intrinsic factors and less important extrinsic factors. Higher body mass index and body fat and lower dietary calcium intake increase fracture risk in healthy adolescents. Bone mass was found to be 5% to 10% lower in adolescents with fracture than their peers. Adequate nutrition in amount and composition and life style factors are important for skeletal health. While diets rich in saturated fats and refined sugars and lower in protein may be detrimental to bone health, optimal quantities of polyunsaturated fatty acids and complex carbohydrates may be beneficial to bone health. Dietary calcium and vitamin D are key factors in promoting bone health and preventing bone loss. Phosphorus and magnesium as well as other elements and especially vitamin C and K have been shown to play important roles in bone health. While weight bearing regular exercise and a healthy bodyweight are beneficial to bone health, alcohol consumption and smoking contribute to poor bone health. Adolescence may serve as a period of opportunity for reduction of the incidence of osteoporosis in adulthood through implication of effective intervention strategies. (Turk Arch Ped 2011; 46 Suppl: 54-8

Oya

2011-03-01

357

Increased stress reactivity is associated with reduced hippocampal activity and neuronal integrity along with changes in energy metabolism.  

Science.gov (United States)

Patients suffering from major depression have repeatedly been reported to have dysregulations in hypothalamus-pituitary-adrenal (HPA) axis activity along with deficits in cognitive processes related to hippocampal and prefrontal cortex (PFC) malfunction. Here, we utilized three mouse lines selectively bred for high (HR), intermediate, or low (LR) stress reactivity, determined by the corticosterone response to a psychological stressor, probing the behavioral and functional consequences of increased vs. decreased HPA axis reactivity on the hippocampus and PFC. We assessed performance in hippocampus- and PFC-dependent tasks and determined the volume, basal activity, and neuronal integrity of the hippocampus and PFC using in vivo manganese-enhanced magnetic resonance imaging and proton magnetic resonance spectroscopy. The hippocampal proteomes of HR and LR mice were also compared using two-dimensional gel electrophoresis and mass spectrometry. HR mice were found to have deficits in the performance of hippocampus- and PFC-dependent tests and showed decreased N-acetylaspartate levels in the right dorsal hippocampus and PFC. In addition, the basal activity of the hippocampus, as assessed by manganese-enhanced magnetic resonance imaging, was reduced in HR mice. The three mouse lines, however, did not differ in hippocampal volume. Proteomic analysis identified several proteins that were differentially expressed in HR and LR mice. In accordance with the notion that N-acetylaspartate levels, in part, reflect dysfunctional mitochondrial metabolism, these proteins were found to be involved in energy metabolism pathways. Thus, our results provide further support for the involvement of a dysregulated HPA axis and mitochondrial dysfunction in the etiology and pathophysiology of affective disorders. PMID:22288479

Knapman, Alana; Kaltwasser, Sebastian F; Martins-de-Souza, Daniel; Holsboer, Florian; Landgraf, Rainer; Turck, Christoph W; Czisch, Michael; Touma, Chadi

2012-02-01

358

Bone Densitometry  

Medline Plus

Full Text Available ... less frequently. Osteoporosis is a major cause of hip and vertebral fractures in older people. Our bones are continually being replaced. New bone is deposited while the body recycles old bone. ... easier. New bone in the hips and vertebrae has the highest possibility of becoming ...

359

Whale bones  

Science.gov (United States)

Vertebrates, or animals that have a skeletal structure for body support, leave bones behind after their death. These bones can be placed together to recreate the skeletal frame of that animal. Bones can be examined to determine what animal the bones came from.

N/A N/A (Go Card USA;)

2007-12-21