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1

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

Energy Technology Data Exchange (ETDEWEB)

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.

Thiryayi, W.A.; Thiryayi, S.A. [Department of Histopathology, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL (United Kingdom); Freemont, A.J. [Division of Regenerative Medicine, University of Manchester, Oxford Road, Manchester M13 9PT (United Kingdom)], E-mail: tony.freemont@manchester.ac.uk

2008-07-15

2

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

International Nuclear Information System (INIS)

[en] 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

2008-01-01

3

Reactive endosteal bone formation  

International Nuclear Information System (INIS)

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. (orig.).

1987-01-01

4

Reactive endosteal bone formation  

Energy Technology Data Exchange (ETDEWEB)

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

5

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Ozdemir Nail; Gelal Mustafa; Minoglu Mustafa; Celik Levent

6

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

Science.gov (United States)

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. PMID:19770557

Ozdemir, Nail; Gelal, Mustafa Fazil; Minoglu, Mustafa; Celik, Levent

7

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

UK PubMed Central (United Kingdom)

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 N; Gelal MF; Minoglu M; Celik L

2009-07-01

8

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

Directory of Open Access Journals (Sweden)

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; Gelal Mustafa; Minoglu Mustafa; Celik Levent

2009-01-01

9

Bone changes in phenylketonuria  

Energy Technology Data Exchange (ETDEWEB)

While treating 14 phenylketonurial (PKU) patients, we evaluated bone density, changes in bone age, and bony changes such as spiculation or metaphyseal widening. A total of 14 PKU patients aged between 1 month and 14 years (mean, 6.4 years) were under dietary treatment. Eight and eleven patients underwent radiography of the left hand and wrist and bone densitometry (BMD) of the lumbar spine, respectively. The results were reviewed with regard to abnormal bony changes, delayed bone age, and osteopenia. Patients were assigned to either the early or late treatment group, depending on whether or not dietary therapy was started before 3 months of age. Those in whom a blood phenylalanine level of under 10 mg/dl was maintained were assigned to the good control group; others were classified as variable control. The findings of radiographs of the left hand and lumbar BMD were evaluated in relation to the time of dietary therapy, and adequacy of treatment. None of the 14 PKU patients who underwent dietary therapy had bony abnormalities such as spiculation or metaphyseal widening. In four of the 11, bone age was at least one year less than chronological age, and on lumbar BMD, osteoporosis was seen. For the evaluation of bone change in PKU patients, plain radiography and BMD are thus complementary. (author). 18 refs., 1 tab., 2 figs.

Hong, Hyun Sook; Lee, Hae Kyung; Kwon, Kui Hyang; Choi, Deuk Lin; Lee, Dong Hwan [Soonchunhyang Univ., Seoul (Korea, Republic of). Hospital

1998-02-01

10

Bone changes in leprosy  

International Nuclear Information System (INIS)

Bone lesions is a frequent organic manifestation in leprosy. Osseal destructions caused by granulomatous process induced by M. leprae are so-called specific lesions in contrast to non specific lesions based on nerval or arterial diseases. The specific osseal alterations are characterized by cystic brightenings in roentgenograms while non specific osseal changes show absorption to bone structure as akroosterolysis and osteoporosis. Typical radiologic findings in different stages of mutilation are demonstrated. (orig.)

1985-01-01

11

Bone changes in leprosy  

Energy Technology Data Exchange (ETDEWEB)

Bone lesions is a frequent organic manifestation in leprosy. Osseal destructions caused by granulomatous process induced by M. leprae are so-called specific lesions in contrast to non specific lesions based on nerval or arterial diseases. The specific osseal alterations are characterized by cystic brightenings in roentgenograms while non specific osseal changes show absorption to bone structure as akroosterolysis and osteoporosis. Typical radiologic findings in different stages of mutilation are demonstrated.

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

1985-02-01

12

Bone changes in tuberous sclerosis mimicking metastases  

International Nuclear Information System (INIS)

Sclerotic and lytic bone changes of tuberous sclerosis (TS) can mimic bone metastases. A case is reported of a patient with concomitant sclerotic bone metastases from bronchogenic carcinoma and TS bone changes, diagnosed by bone scintigraphy and magnetic resonance imaging. The increased bone uptake and abnormal magnetic resonance signal allowed distinction of TS bone lesions from bone metastases. 6 refs., 4 figs.

1996-01-01

13

Bone changes in tuberous sclerosis mimicking metastases  

Energy Technology Data Exchange (ETDEWEB)

Sclerotic and lytic bone changes of tuberous sclerosis (TS) can mimic bone metastases. A case is reported of a patient with concomitant sclerotic bone metastases from bronchogenic carcinoma and TS bone changes, diagnosed by bone scintigraphy and magnetic resonance imaging. The increased bone uptake and abnormal magnetic resonance signal allowed distinction of TS bone lesions from bone metastases. 6 refs., 4 figs.

Pui, M.H.; Kong Hwai Loong; Choo Hui Fen [National University Hospital (Singapore). Depts. of Diagnostic Radiology and Oncology

1996-02-01

14

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

International Nuclear Information System (INIS)

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.)

2002-01-01

15

[Diagnostic spectrum of reactive lymph node changes].  

UK PubMed Central (United Kingdom)

Diagnostic lymph node pathology is primarily focused on identification, definition and classification of lymphoid neoplasms. Less attention is paid to reactive lymph node changes as their causes often cannot be elucidated. We outline several particular types of lymph node reactions that allow a delineation of potential causative agents. A thorough understanding of the morphology of reactive lymph node changes can also aid in the differential diagnosis between reactive and neoplastic lymph node changes.

Hartmann S; Kriener S; Hansmann ML

2008-07-01

16

Bone changes in primary myogenic limb sarcomas  

International Nuclear Information System (INIS)

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.

1986-01-01

17

MRI findings in sclerotic bone changes  

Energy Technology Data Exchange (ETDEWEB)

We have compared the value of MRI with conventional radiography and CT in 40 predominantly sclerotic skeletal lesions. We have found that sclerosis and other changes in the bone structure can be demonstrated by MRI in much the same way as with conventional radiography and CT. Using high resolution surface coils, it is possible to demonstrate small areas of new bone formation such as periosteal new bone or the calcification within the nidus of an osteoid osteoma. MRI is particularly appropriate if it is necessary to show soft tissue changes within an area of sclerosis, which may be responsible for the new bone formation and which may be masked on radiographs and CT by the surrounding sclerosis.

Holland, B.R.; Freyschmidt, J.

1988-11-01

18

Climate change impacts of US reactive nitrogen.  

UK PubMed Central (United Kingdom)

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.

Pinder RW; Davidson EA; Goodale CL; Greaver TL; Herrick JD; Liu L

2012-05-01

19

Bone marrow changes related to disuse.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To evaluate bone marrow changes on knee magnetic resonance imaging (MRI) in patients with 3- to 6-week-long period of unloading. METHODS: MRI knee examinations were performed in 30 patients (14 men, 16 women; aged 20-53 years) at baseline and 5-10 weeks after immobilisation of the ipsilateral lower extremity; subsets of patients were examined at additional time-points. Ten volunteers (4 men, 6 women; aged 20-50 years) were studied as control cohort at two time-points. Bone marrow signal abnormalities were analysed according to: (1) severity, (2) signal alteration relative to hyaline cartilage, (3) morphology, (4) increased vascularity in the knee joint and (5) T1-signal alteration. Spearman's rank correlation test (SRC) and Kendall's tau (KT) were used to compare individual scores. RESULTS: All 30 patients presented abnormal bone marrow findings after unloading, which reached a peak at 10-25 weeks (P <0.001). These findings decreased within 1 year (P?bone marrow (SCR?=?0.923, P?bone marrow related to unloading are consistent findings and most prominent 10-25 weeks following immobilisation when both confluent and patchy hyperintense patterns are present. KEY POINTS: • Disuse is associated with hyperintense MRI signal alteration on fluid-sensitive sequence. • Disuse findings are more prominent at the patella and femoral epiphyses. • Disuse MRI findings appear to be characterised by a specific chronological pattern.

Nardo L; Sandman DN; Virayavanich W; Zhang L; Souza RB; Steinbach L; Guindani M; Link TM

2013-07-01

20

Reactive post-radiotherapy bone formation in the maxilla.  

UK PubMed Central (United Kingdom)

OBJECTIVE: High-dose radiation therapy affects bone metabolism, and therefore post-radiotherapy bone formation is an uncommon finding. This case describes an unusual ossification in the maxillary region identified after head and neck radiotherapy. RESULTS: A 45-year-old female patient was submitted to maxillary surgical resection and orbital exenteration due to squamous cell carcinoma. Radiotherapy post-surgery was performed because of compromised surgical margins. After 4 months of the conclusion of radiotherapy, the patient presented a bone exposition at surgical site. Surprisingly, the oral examination and computed tomography revealed a new formation of the right palatine vault and bone formation filling the nasal and orbital cavity. The incisional biopsy discarded residual disease or osteoradionecrosis and showed normal tissue. CONCLUSIONS: To the best of the authors' knowledge, this is the first case of wide bone formation as an early effect of head and neck radiotherapy.

Mariano FV; Gondak RO; Santos-Silva AR; Corrêa MB; Almeida OP; Lopes MA

2013-01-01

 
 
 
 
21

[Bone micro-structural changes following osteoporotic drug treatment].  

UK PubMed Central (United Kingdom)

Osteoporotic drugs improve bone mechanical integrity by increasing bone mass and also by improving bone structure and quality, where controlling bone metabolism. Changes in trabecular microstructure can be detected since early period after starting drug treatment. Effects on bone metabolism of anti-resorptive agent of bisphosphonates are totally opposite from those of anabolic agent of teriparatide, however these different drug treatments results in the improvement of trabecular microstructure as well.

Mori S

2013-07-01

22

[Bone micro-structural changes following osteoporotic drug treatment].  

Science.gov (United States)

Osteoporotic drugs improve bone mechanical integrity by increasing bone mass and also by improving bone structure and quality, where controlling bone metabolism. Changes in trabecular microstructure can be detected since early period after starting drug treatment. Effects on bone metabolism of anti-resorptive agent of bisphosphonates are totally opposite from those of anabolic agent of teriparatide, however these different drug treatments results in the improvement of trabecular microstructure as well. PMID:23811592

Mori, Satoshi

2013-07-01

23

Cytoplasmic reactive oxygen species and SOD1 regulate bone mass during mechanical unloading.  

UK PubMed Central (United Kingdom)

Oxidative stress contributes to the pathogenesis of age-related diseases as well as bone fragility. Our previous study demonstrated that copper/zinc superoxide dismutase (Sod1)-deficient mice exhibit the induction of intracellular reactive oxygen species (ROS) and bone fragility due to low-turnover bone loss and impaired collagen cross-linking (Nojiri, H., Saita, Y., Morikawa, D., Kobayashi, K., Tsuda, C., Miyazaki, T., Saito, M., Marumo, K., Yonezawa, I., Kaneko, K., Shirasawa, T., Shimizu, T. (2011) J. Bone. Miner. Res. 26, 2682-2694). Mechanical stress also plays an important role in the maintenance of homeostasis in bone tissue. However, the molecular links between oxidative and mechanical stresses in bone tissue have not been fully elucidated. We herein report that mechanical unloading significantly increased intracellular ROS production and the specific up-regulation of Sod1 in bone tissue in a tail-suspension experiment. We also reveal that Sod1 loss exacerbated bone loss via reduced osteoblastic abilities during mechanical unloading. Interestingly, we found that the administration of an antioxidant, vitamin C, significantly attenuated bone loss during unloading. These results indicate that mechanical unloading, in part, regulates bone mass via intracellular ROS generation and the Sod1 expression, suggesting that activating Sod1 may be a preventive strategy for ameliorating mechanical unloading-induced bone loss.

Morikawa D; Nojiri H; Saita Y; Kobayashi K; Watanabe K; Ozawa Y; Koike M; Asou Y; Takaku T; Kaneko K; Shimizu T

2013-05-01

24

Cytoplasmic reactive oxygen species and SOD1 regulate bone mass during mechanical unloading.  

Science.gov (United States)

Oxidative stress contributes to the pathogenesis of age-related diseases as well as bone fragility. Our previous study demonstrated that copper/zinc superoxide dismutase (Sod1)-deficient mice exhibit the induction of intracellular reactive oxygen species (ROS) and bone fragility due to low-turnover bone loss and impaired collagen cross-linking (Nojiri, H., Saita, Y., Morikawa, D., Kobayashi, K., Tsuda, C., Miyazaki, T., Saito, M., Marumo, K., Yonezawa, I., Kaneko, K., Shirasawa, T., Shimizu, T. (2011) J. Bone. Miner. Res. 26, 2682-2694). Mechanical stress also plays an important role in the maintenance of homeostasis in bone tissue. However, the molecular links between oxidative and mechanical stresses in bone tissue have not been fully elucidated. We herein report that mechanical unloading significantly increased intracellular ROS production and the specific up-regulation of Sod1 in bone tissue in a tail-suspension experiment. We also reveal that Sod1 loss exacerbated bone loss via reduced osteoblastic abilities during mechanical unloading. Interestingly, we found that the administration of an antioxidant, vitamin C, significantly attenuated bone loss during unloading. These results indicate that mechanical unloading, in part, regulates bone mass via intracellular ROS generation and the Sod1 expression, suggesting that activating Sod1 may be a preventive strategy for ameliorating mechanical unloading-induced bone loss. PMID:23674366

Morikawa, Daichi; Nojiri, Hidetoshi; Saita, Yoshitomo; Kobayashi, Keiji; Watanabe, Kenji; Ozawa, Yusuke; Koike, Masato; Asou, Yoshinori; Takaku, Tomoiku; Kaneko, Kazuo; Shimizu, Takahiko

2013-05-14

25

Radiographic study of bone changes on TMJ arthrosis  

Energy Technology Data Exchange (ETDEWEB)

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 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.

You, Dong Soo [Dept. of Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1982-11-15

26

Radiographic study of bone changes on TMJ arthrosis  

International Nuclear Information System (INIS)

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 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.

1982-01-01

27

Light changes the atmospheric reactivity of soot.  

Science.gov (United States)

Soot particles produced by incomplete combustion processes are one of the major components of urban air pollution. Chemistry at their surfaces lead to the heterogeneous conversion of several key trace gases; for example NO(2) interacts with soot and is converted into HONO, which rapidly photodissociates to form OH in the troposphere. In the dark, soot surfaces are rapidly deactivated under atmospheric conditions, leading to the current understanding that soot chemistry affects tropospheric chemical composition only in a minor way. We demonstrate here that the conversion of NO(2) to HONO on soot particles is drastically enhanced in the presence of artificial solar radiation, and leads to persistent reactivity over long periods. Soot photochemistry may therefore be a key player in urban air pollution. PMID:20080580

Monge, Maria Eugenia; D'Anna, Barbara; Mazri, Linda; Giroir-Fendler, Anne; Ammann, Markus; Donaldson, D J; George, Christian

2010-01-06

28

Method for assessment of vascular reactivity in bone: in vitro studies on resistance arteries isolated from porcine cancellous bone  

DEFF Research Database (Denmark)

Knowledge about vascular regulation in bone is central to the understanding of both normal and pathological bone physiology. This article describes a new method for direct assessment of the reactivity of bone blood vessels. Resistance arteries (diameter approximately 250 microns) were isolated from epiphyseal cancellous bone (porcine femoral condyle). Arterial segments (2 mm long) were mounted as ring preparations on a myograph, and isometric force development was measured continuously. Fifty-nine vessels from 31 pigs were investigated. The active force development was maximal at 0.9 x L100 in nine of 12 investigated arteries (L100 corresponds to the circumference the vessel would have if relaxed and exposed to a luminal pressure of 100 mm Hg [13.3 kPa]). In all subsequent experiments, the vessels were stretched to 0.9 x L100. Noradrenaline (2 x 10(-8) to 10(-5) M) induced a concentration-dependent vasoconstriction; mean maximal tension development was 3.69 N/m. This force development would enable the arteries to contract against a pressure of more than 22 kPa (165 mm Hg), indicating preserved function of the media smooth muscle. Response to acetylcholine (10(-7) to 10(-5) M) was observed in only two of 12 arteries. Bradykinin (10(-11) to 10(-6) M) induced a concentration-dependent and reproducible relaxation in all vessels; the relaxation was endothelium-dependent, since no effect of bradykinin was detected after mechanical removal of the endothelium. Sodium nitroprusside (10(-4) M) induced a reproducible and endothelium-independent vasorelaxation. The results demonstrate preserved function of both smooth muscle and endothelium in this preparation. The model allows pharmacological investigations of bone arteries under well defined conditions and enables studies on focal bone lesions and human bone tissue.

Lundgaard, A; Aalkjær, Christian

1996-01-01

29

MR imaging of therapy-induced changes of bone marrow  

International Nuclear Information System (INIS)

[en] MR imaging of bone marrow infiltration by hematologic malignancies provides non-invasive assays of bone marrow cellularity and vascularity to supplement the information provided by bone marrow biopsies. This article will review the MR imaging findings of bone marrow infiltration by hematologic malignancies with special focus on treatment effects. MR imaging findings of the bone marrow after radiation therapy and chemotherapy will be described. In addition, changes in bone marrow microcirculation and metabolism after anti-angiogenesis treatment will be reviewed. Finally, new specific imaging techniques for the depiction of regulatory events that control blood vessel growth and cell proliferation will be discussed. Future developments are directed to yield comprehensive information about bone marrow structure, function and microenvironment. (orig.)

2007-01-01

30

Nonspecific suppressor T cells cause decreased mixed lymphocyte culture reactivity in bone marrow transplant patients  

Energy Technology Data Exchange (ETDEWEB)

Decreased reactivity in mixed lymphocyte culture (MLC) was observed in patients within 1 yr after allogeneic and autologous bone marrow transplantation. Suppressor activity of peripheral blood mononuclear cells (PBMC) from transplant patients was studied by adding these cells as modulator cells to a bidirectional MLC with cells from normal individuals. PBMC from transplant patients markedly suppressed MLC reactivity in a dose-dependent manner. Suppressor activity was present in cells forming rosettes with sheep erythrocytes. Treatment of modulator cells with monoclonal antibodies against T cell differentiation antigens (OKT8, OKIa1) and complement completely abolished suppression of MLC. Suppressor activity was unaffected by 30 Gy irradiation. Suppressor activity declined gradually after transplantation and was inversely correlated with MLC reactivity of each patient at a significant level (p less than 0.01). These observations suggest that OKT8+ Ia+ radioresistant suppressor T cells play a role in the development of decreased MLC reactivity observed during the early post-transplant period.

Harada, M.; Ueda, M.; Nakao, S.; Kondo, K.; Odaka, K.; Shiobara, S.; Matsue, K.; Mori, T.; Matsuda, T.

1986-07-15

31

[New classification of bone dysplasias based on histogenetic changes].  

Science.gov (United States)

Several attempts have been made to classify constitutional diseases of ossification. The one from the Roman group is at present the most accepted. Based on histogenetic concepts and on conventional microscopic studies of our casuistics, we are proposing a new systematization of bone dysplasias considering the mechanisms that lead to the transformation of primitive bone tissue into adult bone tissue. Changes in bone histogenesis may take place at the following levels: 1. In the bones of connective ossification. 2. In the chondrocytic fertile cartilage. 3. In the bony trabeculae. 4. In the periosteum and endosteum. 5. In the bony fibrose tissue. Based on such changes, we classify bone dysplasias into: 1. Connective-dysplasias. 2. Chondro-dysplasias. 3. Trabecular-dysplasias. 4. Periosteo-endosteo-dysplasias. 5. Fibro-dysplasias. 6. Mixed types. PMID:758189

Collado, F

32

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

International Nuclear Information System (INIS)

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 of rhBMP-2. (paper)

2012-04-01

33

Histomorphometrical analysis following augmentation of infected extraction sites exhibiting severe bone loss and primarily closed by intrasocket reactive soft tissue.  

UK PubMed Central (United Kingdom)

BACKGROUND: Intrasocket reactive soft tissue can be used for primary closure during augmentation of infected extraction sites exhibiting severe bone loss prior to implant placement. The present study evaluated the histological characteristics of the initially used intrasocket reactive soft tissue, the overlying soft tissue, and the histomorphometry of the newly formed bone during implant placement. MATERIALS AND METHODS: Thirty-six consecutive patients (43 sites) were included in the study. Extraction sites demonstrating extensive bone loss on preoperative periapical and panoramic radiographs served as inclusion criteria. Forty-three implants were inserted after a healing period of 6 months. Porous bovine xenograft bone mineral was used as a single bone substitute. The intrasocket reactive soft tissue was sutured over the grafting material to seal the coronal portion of the socket. Biopsies of the intrasocket reactive soft tissue at augmentation, healed mucosa, and bone cores at implant placement were retrieved and evaluated. RESULTS: The intrasocket reactive soft tissue demonstrated features compatible with granulation tissue and long junctional epithelium. The mucosal samples at implant placement demonstrated histopathological characteristics of keratinized mucosa with no residual elements of granulation tissue. Histomorphometrically, the mean composition of the bone cores was - vital bone 40 ± 19% (13.7-74.8%); bone substitute 25.7 ± 13% (0.6-51%); connective tissue 34.3 ± 15% (13.8-71.9%). CONCLUSIONS: Intrasocket reactive soft tissue used for primary closure following ridge augmentation is composed of granulation tissue and long junctional epithelium. At implant placement, clinical and histological results demonstrate its replacement by keratinized gingiva. The histomorphometrical results reveal considerable bone formation. Fresh extraction sites of hopeless teeth demonstrating chronic infection and severe bone loss may be grafted simultaneously with their removal.

Mardinger O; Vered M; Chaushu G; Nissan J

2012-06-01

34

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

UK PubMed Central (United Kingdom)

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.

Licata AA

2013-02-01

35

Facial surface changes after cleft alveolar bone grafting.  

UK PubMed Central (United Kingdom)

PURPOSE: The aim of this study was to assess the 3-dimensional facial surface changes after cleft alveolar bone grafting with digital surface photogrammetry. PATIENTS AND METHODS: In a prospective study, 22 patients with cleft lip and palate underwent alveolar bone grafting. Before the procedure and 6 weeks postoperatively and before the continuation of orthodontic treatment, 3-dimensional images were taken with digital surface photogrammetry. Seven standard craniofacial landmarks on the nose and the upper lip were identified. Their spatial change because of bone grafting was assessed. Statistical analysis was performed with analysis of variance and t test. RESULTS: A significant increase in anterior projection on the operative side (P < .05) was found for the labial insertion points of the alar base (subalare). No significant changes were detected for the position of the labial landmarks. CONCLUSION: Our results show 3-dimensionally that there is a positive influence of the alveolar bone graft on the projection of the alar base on the cleft side.

Krimmel M; Schuck N; Bacher M; Reinert S

2011-01-01

36

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

International Nuclear Information System (INIS)

[en] 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

1999-01-01

37

Bone and cartilage demonstrate changes localized to bone marrow edema-like lesions within osteoarthritic knees.  

UK PubMed Central (United Kingdom)

OBJECTIVE: Our objective is to understand the biological and mechanical pathways linking cartilage, bone, and marrow changes in the progression of osteoarthritis (OA). The aim of the present study was to evaluate bone structure and composition within bone marrow edema-like lesion (BMEL) regions associated with knee OA. METHODS: Tibial plateau specimens (n = 18) were collected from 10 subjects with knee OA during total knee arthroplasty (TKA). Magnetic resonance (MR) imaging was used to identify BMEL and quantify metrics of cartilage composition. Micro-computed tomography (?CT) and high-resolution peripheral quantitative computed tomography (HR-pQCT) were used to quantify density and microstructure of the subchondral trabecular bone. Fourier transform infrared (FTIR) spectroscopy was used to quantify tissue composition. RESULTS: Trabecular bone within BMEL was higher in volume fraction, with more and thicker trabeculae that were more plate-like in structure compared to unaffected regions. BMEL trabecular tissue composition had decreased phosphate and carbonate content. Marrow infiltration by a fibrous collagen network and evidence of increased bone remodeling were present. Structural and compositional changes were specifically localized to regions underlying cartilage degradation. CONCLUSION: These results support the paradigm of focal interactions among bone, marrow, and cartilage in the progression of knee OA. Quantitative evaluation of tissue changes and interactions may aid in the understanding of disease pathophysiology and provide imaging markers for disease progression.

Kazakia GJ; Kuo D; Schooler J; Siddiqui S; Shanbhag S; Bernstein G; Horvai A; Majumdar S; Ries M; Li X

2013-01-01

38

Bone changes caused by experimental Solanum malacoxylon poisoning in rabbits  

Directory of Open Access Journals (Sweden)

Full Text Available 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 also 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

2005-01-01

39

Bone changes caused by experimental Solanum malacoxylon poisoning in rabbits  

Scientific Electronic Library Online (English)

Full Text Available 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 also 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 (more) 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.

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

2005-03-01

40

Effects of temperature on bone tissue. Histological study of the changes in the bone matrix.  

UK PubMed Central (United Kingdom)

The analysis of burned human remains has given rise to many publications in the literature and has caused great interest among forensic specialists and physical anthropologists due to the difficulty in its analysis and interpretation. The main goal of this study has been to measure the changes that occur in bone matrix as a consequence of the increased temperature and establishing categories of histological morphology in relation to fire temperature. To this end, a total of 150 bone cylinders from the ilium obtained by bone biopsy. These samples have been obtained from forensic cadavers and burned at controlled temperatures between 100 and 1100°C in an oven. The samples were fixed in methyl methacrylate and stained with hematoxylin-eosin, Goldner's trichrome and toluidine blue stains. The samples were studied using an optical microscope at 100×. Our study classifies the morphological changes that occur in bone matrix in four stages as a result of the temperature.

Castillo RF; Ubelaker DH; Acosta JA; de la Fuente GA

2013-03-01

 
 
 
 
41

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.

2012-01-01

42

Age-related changes in trabecular and cortical bone microstructure.  

Science.gov (United States)

The elderly population has substantially increased worldwide. Aging is a complex process, and the effects of aging are myriad and insidious, leading to progressive deterioration of various organs, including the skeleton. Age-related bone loss and resultant osteoporosis in the elderly population increase the risk for fractures and morbidity. Osteoporosis is one of the most common conditions associated with aging, and age is an independent risk factor for osteoporotic fractures. With the development of noninvasive imaging techniques such as computed tomography (CT), micro-CT, and high resolution peripheral quantitative CT (HR-pQCT), imaging of the bone architecture provides important information about age-related changes in bone microstructure and estimates of bone strength. In the past two decades, studies of human specimens using imaging techniques have revealed decreased bone strength in older adults compared with younger adults. The present paper addresses recently studied age-related changes in trabecular and cortical bone microstructure based primarily on HR-pQCT and micro-CT. We specifically focus on the three-dimensional microstructure of the vertebrae, femoral neck, and distal radius, which are common osteoporotic fracture sites. PMID:23573086

Chen, Huayue; Zhou, Xiangrong; Fujita, Hiroshi; Onozuka, Minoru; Kubo, Kin-Ya

2013-03-18

43

Age-related changes in trabecular and cortical bone microstructure.  

UK PubMed Central (United Kingdom)

The elderly population has substantially increased worldwide. Aging is a complex process, and the effects of aging are myriad and insidious, leading to progressive deterioration of various organs, including the skeleton. Age-related bone loss and resultant osteoporosis in the elderly population increase the risk for fractures and morbidity. Osteoporosis is one of the most common conditions associated with aging, and age is an independent risk factor for osteoporotic fractures. With the development of noninvasive imaging techniques such as computed tomography (CT), micro-CT, and high resolution peripheral quantitative CT (HR-pQCT), imaging of the bone architecture provides important information about age-related changes in bone microstructure and estimates of bone strength. In the past two decades, studies of human specimens using imaging techniques have revealed decreased bone strength in older adults compared with younger adults. The present paper addresses recently studied age-related changes in trabecular and cortical bone microstructure based primarily on HR-pQCT and micro-CT. We specifically focus on the three-dimensional microstructure of the vertebrae, femoral neck, and distal radius, which are common osteoporotic fracture sites.

Chen H; Zhou X; Fujita H; Onozuka M; Kubo KY

2013-01-01

44

[Bone mineral density changes in coal workers' pneumoconiosis].  

UK PubMed Central (United Kingdom)

OBJECTIVE: To observe the bone mineral density changes of coal workers' pneumoconiosis. METHODS: We chosed 150 cases of One-Triple coal workers pneumoconiosis in Jincheng Coal Mining Group, all of workers were male, of 55-years old-80 years old, an average of 67 years old. 10 years of age to grouping, Whole body bone mineral density and T value were measured by body dual-energy X-ray absorptiometry. We analyzed the BMD changes bone loss, osteoporosis occurrence. RESULTS: The BMD of six parts were not declined obviously in One stage of coal workers' pneumoconiosis; the BMD of Chest bone, pelvis and spine were declined obviously in two stage of coal workers' pneumoconiosisl; the BMD of six parts were declined obviously in Triple stage of coal workers' pneumoconiosis; The occurrence rate of bone loss was significantly higher in Two and Triple coal workers pneumoconiosisl. The occurrence rate of osteoporosis was significantly higher in Triple coal workers pneumoconiosis. CONCLUSION: With the increase in the severity of coal workers' pneumoconiosis, the BMD of six parts were declined, The occurrence rate of bone loss osteoporosis was significantly higher.

Li HX; Zhai PY; Yan JF

2012-08-01

45

Alveolar bone density changes around miniscrews: a prospective clinical study.  

UK PubMed Central (United Kingdom)

INTRODUCTION: Our objective was to assess the effects of miniscrews on interproximal alveolar bone density and adjacent gingival tissue health. METHODS: Forty-four titanium miniscrews were inserted between maxillary second premolars and first molars on both sides of the dentition in 22 consecutive patients (15 female, 7 male; ages, 14-24 years). A control area (between the maxillary first and second premolars) was also assessed. Both miniscrew (study) and control areas were monitored clinically and radiographically at different time points: before insertion of the miniscrews and at 1 month, 3 months, and 6 months after insertion. Software associated with a digital intraoral radiography machine was used to assess changes in alveolar bone density. Clinical gingival parameters of the study and control areas were also recorded. A repeated-measures analysis of variance and the Bonferroni post-hoc pairwise comparison tests were used to assess the changes at the different time points. RESULTS: Thirty-nine miniscrews were successful for the study duration. Male subjects had significantly (P <0.001) higher alveolar bone density than did the females at baseline. Alveolar bone density around the miniscrews increased significantly (P <0.001) between 3 and 6 months after insertion upon loading. Alveolar bone density of the control area did not change significantly during the experiment (P >0.05). The width of keratinized gingiva increased significantly (P <0.001) in the study and control areas after insertion of miniscrews and remained with no significant change throughout the study. CONCLUSIONS: Miniscrews increased the alveolar bone density significantly after 3 months of insertion and were not associated with detrimental effects on the adjacent gingival tissues.

Al Maaitah EF; Safi AA; Abdelhafez RS

2012-12-01

46

Florid reactive periostitis ossificans of long bones and digits associated with reaction in a patient with leprosy.  

UK PubMed Central (United Kingdom)

Florid reactive periostitis ossificans is a rare bone lesion usually occurring in the small, tubular bones of the hands and feet. This entity is a benign and aggressive periosteal reaction associated with soft tissue swelling that appears similar to a bone lesion that radiographically and clinically mimics an infectious or neoplastic process. Typically the lesions occurs in an adolescent or young adult and presents as a small area of painful swelling and erythema over the affected bone. The cause of florid reactive periostitis ossificans is not exactly known though many authors have postulated varied etiopathogenesis for the same condition. In this report, is a very rare and unusual example of this entity that has been observed in association with erythema nodosum leprosum (ENL) a type 2 lepra reaction in a Leprosy patient.

Chakma JK; Malaviya GN; Girdhar A; Hussein S

2012-03-01

47

Radiodiagnosis of bone changes in diabetes mellitus  

International Nuclear Information System (INIS)

[en] 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

1986-01-01

48

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 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)

1996-01-01

49

Precision of bone densitometry measurements: When is change true change and does it vary across bone density values?  

International Nuclear Information System (INIS)

[en] The precision error of the bone densitometer is used to interpret significant change in bone mineral density (BMD) in serial studies. The precision error can be expressed as standard deviation (SD) or coefficient of variation (CV). The aims of this study are to determine the precision error over a range of BMD values and to demonstrate the application of the precision error in clinical practice. A bone phantom was used consisting of a perspex block with eight compartments containing varying amounts of hydroxyapatite powder to simulate a range of bone densities. The block was scanned 21 times and manual regions placed over each compartment to measure the BMD in each compartment. There were no significant differences in the variances or SD for all eight compartments, that is, over the range of BMD normally encountered in clinical practice. However, the calculated CV show a progressive fall in values as the BMD rises. Therefore, the SD should be used to calculate significant BMD change. In a practise with quality control procedures in place to detect calibration drift and with appropriately trained personnel, a change of approximately 0.05 g/cm2 is generally regarded as being a significant change at a 95% confidence level. Copyright (2003) Blackwell Science Pty Ltd

2003-01-01

50

Change of MRI images in bone metastasis caused by radiotherapy  

Energy Technology Data Exchange (ETDEWEB)

The effect of radiation therapy on bone metastasis was studied by MR imaging. The study comprised 32 patients with bone metastasis from lung cancer, breast cancer, renal cell carcinoma and various other malignancies that were evaluated by MR imaging before and after radiation therapy (Group I); and 3 patients with preexisting bone metastasis of breast cancer who were free from recurrence for more than 5 years after radiation therapy (Group II). Signal intensities fell into 5 degrees: iso-intense to normal bone marrow within the radiation field (I); iso-intense to the muscles (L); hypointense to the muscles (LL); iso-intense to subcutaneous fat (H); and hyperintense to the fat (HH). Before radition therapy, most bone metastasis was (L) on T1-weighted images or (H) on T2-weighted images with enhancement by Gd-DTPA. MR images within or after 2 years in Group I showed the following T1-/T2-weighted images: LL/HH (31%, Type I), I/I (13%, Type II), LL/LL (9%, Type III), mixed changes (Type IV), and unchanged (NC). Gd-DTPA enhanced images before radiotherapy showed solid pattern in 23 of 27 patients. Among the 23 patients, the enhancement after radiation showed the decrease in 18 patients as follows: mottled (7), ring-shaped (4) and lacking (7). This seemed to have resulted from radiation. Tumor size reduction on MR imags was noted in a total of 12 patients. All 3 patients in Group II had Type III on non-enhanced MR images. Therefore, changes in T1- and T2-weighted images, Gd-DTPA enhancement, and tumor size are considered helpful in the evaluation of therapeutic results of bone metastasis. (N.K.).

Murakami, Masao; Kuroda, Yasumasa; Sano, Akira (Tenri Hospital, Nara (Japan)) (and others)

1991-12-01

51

Change of MRI images in bone metastasis caused by radiotherapy  

International Nuclear Information System (INIS)

[en] The effect of radiation therapy on bone metastasis was studied by MR imaging. The study comprised 32 patients with bone metastasis from lung cancer, breast cancer, renal cell carcinoma and various other malignancies that were evaluated by MR imaging before and after radiation therapy (Group I); and 3 patients with preexisting bone metastasis of breast cancer who were free from recurrence for more than 5 years after radiation therapy (Group II). Signal intensities fell into 5 degrees: iso-intense to normal bone marrow within the radiation field (I); iso-intense to the muscles (L); hypointense to the muscles (LL); iso-intense to subcutaneous fat (H); and hyperintense to the fat (HH). Before radition therapy, most bone metastasis was (L) on T1-weighted images or (H) on T2-weighted images with enhancement by Gd-DTPA. MR images within or after 2 years in Group I showed the following T1-/T2-weighted images: LL/HH (31%, Type I), I/I (13%, Type II), LL/LL (9%, Type III), mixed changes (Type IV), and unchanged (NC). Gd-DTPA enhanced images before radiotherapy showed solid pattern in 23 of 27 patients. Among the 23 patients, the enhancement after radiation showed the decrease in 18 patients as follows: mottled (7), ring-shaped (4) and lacking (7). This seemed to have resulted from radiation. Tumor size reduction on MR imags was noted in a total of 12 patients. All 3 patients in Group II had Type III on non-enhanced MR images. Therefore, changes in T1- and T2-weighted images, Gd-DTPA enhancement, and tumor size are considered helpful in the evaluation of therapeutic results of bone metastasis. (N.K.)

1991-01-01

52

Bone Microarchitecture of the Talus Changes With Aging.  

UK PubMed Central (United Kingdom)

BACKGROUND: Fractures of the talus in the elderly are rare and usually result from high-impact injuries, suggesting only minor age-related bone structure changes. However, total ankle replacement failures with age often result from talar subsidence, suggesting age-related bone loss in the talus. Despite a number of histological analyses of talar microarchitecture, the effects of age and sex on talar microarchitecture changes remain poorly defined. QUESTIONS/PURPOSES: The aim of this study was to analyze changes or differences in the trabecular microarchitecture of the talus with regard to (1) age and (2) sex. METHODS: Sixty human tali were harvested from 30 patients at autopsy of three different age groups (20-40, 41-60, 61-80 years). The specimens were analyzed by radiography, micro-CT, and histological analysis. Given that there was no difference between the left and right talus, static histomorphometric parameters were assessed in three regions of interest of the right talus only (body, neck, head; n = 30). RESULTS: The talar body, neck, and head were affected differently by age-related changes. The greatest loss of bone volume with age was seen in the talar body (estimate: -0.239; 95% confidence interval [CI], -0.365 to -0.114; p < 0.001). In the talar neck (estimate: -0.165; 95% CI, -0.307 to -0.023; p = 0.025), bone loss was only moderate and primarily was the result of reduction in trabecular thickness (estimate: -1.288; 95% CI, -2.449 to -0.127; p = 0.031) instead of number (estimate: -0.001; 95% CI, -0.005 to -0.003; p = 0.593). Bone structure changes were independent of sex. CONCLUSIONS: Age-related bone structure changes predominantly occur in the talar body, which poses a potential risk factor for total ankle replacement loosening. The moderate changes in the talar neck might explain the persistent low incidence of talar neck fractures with age. CLINICAL RELEVANCE: Our findings suggest that before total ankle replacement implantation, careful patient selection with dual-energy xray absorptiometry evaluation may be necessary to reduce the risk of talar implant subsidence.

Krause M; Rupprecht M; Mumme M; Püschel K; Amling M; Barvencik F

2013-07-01

53

Bone mineral content and bone mineral metabolism: changes after growth hormone treatment in juvenile chronic arthritis.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To determine whether growth hormone (rhGH) affects bone mineral metabolism and bone mineral content (BMC, g/cm) in a therapeutic trial of recombinant growth hormone in growth retarded children with juvenile chronic arthritis (JCA) treated with steroid. METHODS: BMC was measured in 20 children (of whom 17 were treated with corticosteroid) before and after one year of rhGH. Children were randomized to receive either low dose (12 IU/m2/week) or high dose (24 IU/m2/week) for one year. Three monthly assessments were made of disease activity and anthropomorphic measurements. Blood and urine samples were also obtained to measure indicators of disease activity, bone remodeling, and vitamin D and parathyroid hormone (PTH) status. RESULTS: BMC increased during the treatment period and correlated with increasing height. Osteocalcin levels, normally indicators of bone formation, increased after rhGH treatment and correlated significantly with height velocity, particularly for the high dose treatment group. In contrast, osteocalcin levels were negatively correlated with C-reactive protein levels, both before and during treatment. Height velocity, vitamin D, PTH, and osteocalcin levels were significantly lower than age matched controls before treatment. CONCLUSION: Steroid treated children with both JCA and severe growth retardation have reduced vitamin D, PTH, and osteocalcin levels. After treatment with rhGH, height velocity increased, as did BMC. Growth hormone might be a useful adjunct in the treatment of severe growth retardation and osteoporosis in children with JCA. The longterm benefits of rhGH in the treatment of osteoporosis remain unclear.

Rooney M; Davies UM; Reeve J; Preece M; Ansell BM; Woo PM

2000-04-01

54

Changes in bone structure and the muscle-bone unit in children with chronic kidney disease.  

UK PubMed Central (United Kingdom)

The impact of pediatric chronic kidney disease (CKD) on acquisition of volumetric bone mineral density (BMD) and cortical dimensions is lacking. To address this issue, we obtained tibia quantitative computed tomography scans from 103 patients aged 5-21 years with CKD (26 on dialysis) at baseline and 12 months later. Gender, ethnicity, tibia length, and/or age-specific Z-scores were generated for trabecular and cortical BMD, cortical area, periosteal and endosteal circumference, and muscle area based on over 700 reference subjects. Muscle area, cortical area, and periosteal and endosteal Z-scores were significantly lower at baseline compared with the reference cohort. Cortical BMD, cortical area, and periosteal Z-scores all exhibited a significant further decrease over 12 months. Higher parathyroid hormone levels were associated with significantly greater increases in trabecular BMD and decreases in cortical BMD in the younger patients (significant interaction terms for trabecular BMD and cortical BMD). The estimated glomerular filtration rate was not associated with changes in BMD Z-scores independent of parathyroid hormone. Changes in muscle and cortical area were significantly and positively associated in control subjects but not in CKD patients. Thus, children and adolescents with CKD have progressive cortical bone deficits related to secondary hyperparathyroidism and potential impairment of the functional muscle-bone unit. Interventions are needed to enhance bone accrual in childhood-onset CKD.

Tsampalieros A; Kalkwarf HJ; Wetzsteon RJ; Shults J; Zemel BS; Foster BJ; Foerster DL; Leonard MB

2013-03-01

55

Changing memories after reactivation: a one-time opportunity?  

UK PubMed Central (United Kingdom)

After reactivation, apparently stable memories can become sensitive to modifications again, requiring another phase of stabilization, called reconsolidation. Recent evidence shows that repeated reactivations strengthen memories and that stronger memories are more resistant to alterations during reconsolidation. Therefore, we asked whether multiple reactivations make memories less vulnerable to manipulations during reconsolidation and thus serve as boundary condition on memory reconsolidation. In Experiment1, we tested whether new learning after the reactivation of previously learned material alters the subsequent memory for the original material. Participants learned negative and neutral pictures, reactivated them 1week later, and learned new pictures immediately thereafter. Memory for the original pictures was assessed in a recognition test 1day later. We found that new learning after reactivation reduced the subsequent memory of the original pictures; new learning alone or reactivation alone, however, had no effect on memory. Two further experiments investigated the impact of multiple reactivations on this memory impairing effect of new learning after reactivation. These experiments showed that the influence of new learning after reactivation disappeared neither after one (Experiment2) nor after three (Experiment3) additional reactivations completely, indicating that even after multiple reactivations memories remain sensitive to modifications during reconsolidation. These findings may have important implications for novel treatment approaches that aim for modification of unwanted memories during reconsolidation.

Wichert S; Wolf OT; Schwabe L

2013-01-01

56

Bone scintigraphic changes in osteonecrosis of the femoral head  

International Nuclear Information System (INIS)

Bone scanning with /sup 99m/Tc will detect osteonecrosis of the femoral head before changes appear in conventional radiographs. There is no liner correlation between the intensity of the scintigraphic picture and the clinical stage of the disease. The /sup 99m/Tc labels newly formed hydroxyapatite crystals and may be helpful in detecting disease in a contralateral asymptomatic hip or confirming the diagnosis in the suspected hip.

1985-01-01

57

Bone scintigraphic changes in osteonecrosis of the femoral head  

Energy Technology Data Exchange (ETDEWEB)

Bone scanning with /sup 99m/Tc will detect osteonecrosis of the femoral head before changes appear in conventional radiographs. There is no liner correlation between the intensity of the scintigraphic picture and the clinical stage of the disease. The /sup 99m/Tc labels newly formed hydroxyapatite crystals and may be helpful in detecting disease in a contralateral asymptomatic hip or confirming the diagnosis in the suspected hip.

Bonnarens, F.; Hernandez, A.; D' Ambrosia, R.

1985-10-01

58

Bone changes of mandibular condyle using cone beam computed tomography  

Energy Technology Data Exchange (ETDEWEB)

To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibualr disorder (TMD) patients. 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Osteopathy (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior surface of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78{sub 0}.84), but interobserver agreement was fair (k=0.45). CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

Lee, Ji Un; Kim, Hyung Seop; Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon [Chonbuk National Univ., Chonju (Korea, Republic of)

2007-09-15

59

A Model for reactivity changes in coupled systems  

International Nuclear Information System (INIS)

Difficulties in reactivity calculations in coupled reactors are consequences of different neutron spectra in the reactors and intensified local effects. A modified space-independent reactor kinetics model with space dependent feedback reactivities in accident analysis of 'HERBE' fast-thermal coupled system is proposed. A new kinetic model with local parameters for power and reactivity determination in the coupled systems is applied at 'HERBE' flooding accident calculation. Its advantage over model with core-averaged parameters is shown

1994-01-01

60

Suitability of texture features to assess changes in trabecular bone architecture  

DEFF Research Database (Denmark)

The purpose of this study was to determine the ability of texture features to assess changes in trabecular bone architecture as projected in radiographs. Micro-CT datasets of trabecular bone were processed to simulate different changes in architecture. Radiographs were simulated by projecting the 3D-bone structure. Texture features, based on mathematical morphology, determined on the simulated radiographs were able to detect structural changes in the trabecular bone.

Veenland, JF; Grashuis, JL

2002-01-01

 
 
 
 
61

Analysis of monocyte and histiocytic cell populations in bone marrow of patients with confirmed and suspected cases of reactive histocytosis.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To describe characteristics of monocytes and histiocytes in the bone marrow of patients with a confirmed and suspected diagnosis of reactive histiocytosis. METHODS: 14 patients with a confident diagnosis of reactive histiocytosis or with a suspected diagnosis were inpatients at the Tianjin Blood Diseases Hospital between 2008 and 2012. Nucleated cells from bone marrow were observed by light microscopy - morphologically and immunohistochemically for histiocyte antigens - and ultrastructurally by transmission electron microscopy. RESULTS: Monocytes, atypical histiocytes, macrophages, hemophagocytes, reticular cells and dendritic cells were significantly increased in 9, 9, 5, 3, 3 and 2, respectively, of the 14 cases. Atypical histiocytes expressed some morphological characteristics of promonocytes. CONCLUSION: Monocytes, atypical histiocytes, macrophages, hemophagocytes, reticular cells and dendritic cells were increased in different relative degrees in patients with bone marrow reactive histiocytosis or suspected reactive histiocytosis. The increase in numbers of monocytes, atypical histiocytes and macrophages was a particularly significant feature. It is argued that atypical histiocytes with immature monocyte features might be precursors of hemophagocytes, reticular cells or dendritic cells.

Ru YX; Bao ST; Dong SX; Zhao SX; Zhang FK; Zhu XF; Pang TX; Eyden B

2013-04-01

62

Chronological changes in renal vascular reactivity in portal hypertensive rats.  

UK PubMed Central (United Kingdom)

BACKGROUND: Circulatory dysfunction in portal hypertension is characterized by increased cardiac output, decreased systemic vascular resistance, a fall in mean arterial pressure secondary to splanchnic and systemic vasodilation and hence renal hypoperfusion. Previous studies have disclosed that renal vasculatures of portal hypertensive rats had lower perfusion pressure and hyporesponsiveness to endogenous vasoconstrictors. However, the sequences of altered renal haemodynamics have never been described. This study aimed to explore the evolution of renal vascular hyporeactivity and associated mechanisms during portal hypertension. MATERIALS AND METHODS: All rats were randomized into partial portal vein ligation (PVL) or shamed surgery. Isolated kidney perfusion was performed at postoperative day 1, 4, 7 and 14, respectively, to evaluate chronologically renal vascular response to endothelin-1. Renal arteries and kidneys were harvested for further analysis. RESULTS: Impaired renal vascular reactivity to endothelin-1 developed 1 week following PVL. There were extensive up-regulations of vasodilative nitric oxide synthase (NOS) and cyclooxygenase-2 in renal arteries of PVL rats. Among them, the changes in endothelial NOS paralleled with the evolution of renal vascular hyporesponsiveness. Preincubation of NOS inhibitor attenuated the renal vascular hyporeactivity in PVL rats. Up-regulated NOS and down-regulated cyclooxygenase-2 in kidneys of PVL rats might play a critical role to maintain renal circulation and body fluid homoeostasis in response to systemic hypotension. CONCLUSIONS: This investigation highlights the versatile nature of renal vasculatures in portal hypertension, which is replete with compensatory mechanisms. It may help to unveil potential mechanisms of severe renal dysfunction in advanced liver disease.

Chuang CL; Huang HC; Chang CC; Lee FY; Wu JC; Lee SD

2013-03-01

63

Simple bone cyst: radiologic changes after injection of steroid  

International Nuclear Information System (INIS)

To evaluate radiographic changes and clinical effects after the injection of steroid injection into simple bone cyst. We analyzed plain radiographic and CT findings after the injection of steroid (methylprednisolone acetate, MPA) into simple bone cyst. Twelve patients were involved; eight were males and four were females, and their ages ranged from 6 to 41 years. They were treated from one to seven times with an intracystic injection of MPA, 80-200mgs per injection. All patients were evaluated by plain film, and four by CT, and the mean follow-up period was 20 months. Postinjection plain radiographic findings were as follows: increased internal radiodensity (n=3D10), smaller cyst (n=3D8), cortical thickening (n=3D7), and radiodensity of double ring pattern (n=3D4). CT findings were as follows: increased internal attenuation (n=3D4), smaller cyst (n=3D4) and radiodensity of double ring pattern along the cyst wall (n=3D4). All patients improved clinically and radiologically, especially those with radiodensity of double ring pattern. The injection of steroid into simple bone cyst is an effective treatment. A new radiographic finding after injetion is radiodensity of double ring pattern along the cyst wall, and we believe that this indicates progression of the healing process

1997-01-01

64

Periprosthetic bone mineral density changes after unicondylar knee arthroplasty.  

UK PubMed Central (United Kingdom)

BACKGROUND: Unicompartmental knee arthroplasty (UKA) has received renewed interest in the last decade. UKA involves minor injury to soft tissues, limited removal of bone and delicate preservation of knee anatomy and geometry. In theory, UKA provides an opportunity to restore post-surgical knee kinematics to near normal. HYPOTHESIS: UKA leaves patellofemoral joint free to meet high mechanical forces with no stress-shielding and therefore might preserve bone mineral density (BMD). PATIENTS AND METHODS: We studied 21 patients with osteoarthritis (OA), who had received medial compartment UKA at Kuopio University Hospital between October 1997 and September 2000. BMD was measured by dual-energy X-ray absorptiometry (DEXA), at baseline (within a week after surgery) and at intervals until 7 years. RESULTS: DEXA results were reproducible. The highest rate of periprosthetic bone loss occurred during the first 3 months after UKA. The average loss in BMD was 4.4% (p = 0.039) in the femoral diaphysis and it ranged from 11.2% (p < 0.001) to 11.9% (p = 0.002) in the distal femoral metaphysis; however, BMD changes in these regions, from 2 years to 7 years, were nonsignificant. At the 1-year follow-up, the BMD of the medial tibial metaphysis had increased by 8.9% (p = 0.02), whereas those in the lateral tibial metaphysial (-2.4%) and diaphysial regions (-2.0%) did not change significantly. INTERPRETATIONS: UKA did not preserve periprosthetic BMD in the distal femoral metaphysis, whereas BMD changes in the tibial metaphysis were minor, consistent with a mechanical balance between the medial and lateral tibial compartments. LEVEL OF EVIDENCE 2B: Prospective case control study.

Soininvaara TA; Harju KA; Miettinen HJ; Kröger HP

2013-03-01

65

Mandibular bone changes in 24 years and skeletal fracture prediction.  

UK PubMed Central (United Kingdom)

OBJECTIVES: The objectives of the investigation were to describe changes in mandibular bone structure with aging and to compare the usefulness of cortical and trabecular bone for fracture prediction. MATERIALS AND METHODS: From 1968 to 1993, 1,003 women were examined. With the help of panoramic radiographs, cortex thickness was measured and cortex was categorized as: normal, moderately, or severely eroded. The trabeculation was assessed as sparse, mixed, or dense. RESULTS: Visually, the mandibular compact and trabecular bone transformed gradually during the 24 years. The compact bone became more porous, the intertrabecular spaces increased, and the radiographic image of the trabeculae seemed less mineralized. Cortex thickness increased up to the age of 50 and decreased significantly thereafter. At all examinations, the sparse trabeculation group had more fractures (71-78 %) than the non-sparse group (27-31 %), whereas the severely eroded compact group showed more fractures than the less eroded groups only in 1992/1993, 24 years later. Sparse trabecular pattern was associated with future fractures both in perimenopausal and older women (relative risk (RR), 1.47-4.37) and cortical erosion in older women (RR, 1.35-1.55). RR for future fracture associated with a severely eroded cortex increased to 4.98 for cohort 1930 in 1992/1993. RR for future fracture associated with sparse trabeculation increased to 11.43 for cohort 1922 in 1992/1993. CONCLUSION: Dental radiographs contain enough information to identify women most at risk of future fracture. CLINICAL RELEVANCE: When observing sparse mandibular trabeculation, dentists can identify 40-69 % of women at risk for future fractures, depending on participant age at examination.

Jonasson G; Sundh V; Hakeberg M; Hassani-Nejad A; Lissner L; Ahlqwist M

2013-03-01

66

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; A. Szarek

2007-01-01

67

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.

1982-01-01

68

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

UK PubMed Central (United Kingdom)

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; kappa and lambda immunoglobulin light chains; and MC markers chymase, tryptase, and CD117 (KIT). Monoclonal rearrangements of IgH and TCRgamma 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 TCRgamma. 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.

Horny HP; Lange K; Sotlar K; Valent P

2003-08-01

69

Isolation of mesenchymal stem cells from mouse bone marrow: frequent medium change method  

Directory of Open Access Journals (Sweden)

Full Text Available "nBackground: MSCs have been isolated from a variety of mammals by the plastic adherence method. However, this method can be problematic due to the unwanted growth of hematopoietic cells and non-MSCs. The potential of MSCs to differentiate along multiple lineages is the key to the identification of stem cell populations in the absence of molecular markers. In the present study, we describe a homogeneous population of MSCs from mouse bone marrow isolated using an improved plastic adherence method that employs frequent medium change (FMC) at the initial hours of harvested bone marrow cell culture."n"nMethods: Balb/c mice were sacrificed and whole bone marrow cells were aspirated from the femur and tibia and then cultivated in six-well plates. After 3-4 hours of culture, old medium was removed and fresh medium was added. FMC was performed every eight hours over a 72 hour period. When primary cultures became nearly confluent, the first passage was performed. These cells were then used for further examination. To investigate their mesenchymal nature, the cells were allowed to differentiate into mesenchymal lineages and examined at each passage up to the tenth passage for surface antigens by flow cytometry."n"nResults: We achieved purified populations of fibroblast-like cells in the two weeks after culture initiation. The cells were capable of differentiating into osteocytes and adipocytes. Isolated MSCs were reactive to the CD44, Sca-1, and CD90 cell surface markers. MSCs were negative for hematopoietic surface markers such as CD34, CD11b, CD45, CD31, CD106, CD117 and CD135."n"nConclusions: This protocol provides an efficient isolation of homogeneous populations of MSCs from mouse bone marrow.

Soleimani M, Nadri S, Izadpanah R

2008-01-01

70

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; Girish K; Ghatti Suvarna; Stephen T; Kumar V

2001-01-01

71

Changes in bone turnover and bone loss in HIV-infected patients changing treatment to tenofovir-emtricitabine or abacavir-lamivudine.  

UK PubMed Central (United Kingdom)

BACKGROUND: Those receiving tenofovir/emtricitabine (TDF-FTC) had greater bone loss compared with abacavir/lamivudine (ABC-3TC) in a randomized simplification trial (STEAL study). Previous studies associated increased bone turnover and bone loss with initiation of antiretroviral treatment, however it is unclear whether change in bone mineral density (BMD) was a result of specific drugs, from immune reconstitution or from suppression of HIV replication. This analysis determined predictors of BMD change in the hip and spine by dual-energy x-ray absorptiometry in virologically suppressed participants through week 96. METHODOLOGY/PRINCIPAL FINDINGS: Bone turnover markers (BTMS) tested were: formation [bone alkaline phosphatase, procollagen type 1 N-terminal propeptide (P1NP)]; resorption (C-terminal cross-linking telopeptide of type 1 collagen [CTx]); and bone cytokine-signalling (osteoprotegerin, RANK ligand). Independent predictors of BMD change were determined using forward, stepwise, linear regression. BTM changes and fracture risk (FRAX®) at week 96 were compared by t-test. Baseline characteristics (n = 301) were: 98% male, mean age 45 years, current protease-inhibitor (PI) 23%, tenofovir/abacavir-naïve 52%. Independent baseline predictors of greater hip and spine bone loss were TDF-FTC randomisation (p ? 0.013), lower fat mass (p-trend ? 0.009), lower P1NP (p = 0.015), and higher hip T score/spine BMD (p-trend ? 0.006). Baseline PI use was associated with greater spine bone loss (p = 0.004). TDF-FTC increased P1NP and CTx through Wk96 (p<0.01). Early changes in BTM did not predict bone loss at week 96. No significant between-group difference was found in fracture risk. CONCLUSIONS/SIGNIFICANCE: Tenofovir/emtricitabine treatment, lower bone formation and lower fat mass predicted subsequent bone loss. There was no association between TDF-FTC and fracture risk.

Haskelberg H; Hoy JF; Amin J; Ebeling PR; Emery S; Carr A; STEAL Study Group

2012-01-01

72

Subchondral bone grafting reduces degenerative change of knee joint in patients of giant cell tumor of bone.  

UK PubMed Central (United Kingdom)

BACKGROUND: Giant cell tumors (GCTs) most commonly occur around the knee. The most beneficial procedure for this disease has been extensive curettage with reconstruction. However, since many GCTs may compromise the subchondral bone, surgery can further jeopardize the articular cartilage and result in secondary osteoarthritis. In this study, we aimed to determine the factors associated with the development of degenerative arthritis and the effect of bone grafting on the prevention of secondary osteoarthritis. METHODS: We retrospectively analyzed 76 patients with GCT around the knee. The mean age at first diagnosis was 31.1 years. Surgical treatments included extensive curettage and cementation with or without bone grafting in the subchondral bone. Patient follow-up was a median duration of 35 months, ranging from 18 to 113 months. RESULTS: The local recurrence rate was 5.3% (4/76). Secondary degenerative changes occurred in 30.3% (23/76) of the patients. Less than 10 mm of the residual thickness of the remaining subchondral bone was correlated with secondary degenerative changes in 57 patients (P < 0.001). Of these 57 patients, 56.5% (13/23) treated with bone cement reconstruction alone developed secondary degenerative changes; following bone grafting, the rate decreased to 29.4% (10/34), with a statistically significant difference (P = 0.041). CONCLUSIONS: GCT patients with less residual thickness of the subchondral bone are more likely to develop degenerative arthritis after curettage. Bone grafting in the subchondral bone area is recommended when the residual thickness of the subchondral bone is less than 10 mm.

Xu HR; Niu XH; Zhang Q; Hao L; Ding Y; Li Y

2013-08-01

73

Giant Cell Tumor of Bone: A Neoplasm or a Reactive Condition?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Giant cell tumor of bone (GCTB) is a benign but locally aggressive bone tumor of young adults. It typically presents as a large lytic mass at the end of the epiphysis of long bones. Grossly it is comprised of cystic and hemorrhagic areas with little or no periosteal reaction. Microscopically areas o...

Haque, Anwar Ul; Moatasim, Ambreen

74

Bioactive ceramic-based materials with designed reactivity for bone tissue regeneration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Bioactive ceramics have been used clinically to repair bone defects owing to their biological affinity to living bone; i.e. the capability of direct bonding to living bone, their so-called bioactivity. However, currently available bioactive ceramics do not satisfy every clinical application. Therefo...

Ohtsuki, Chikara; Kamitakahara, Masanobu; Miyazaki, Toshiki

75

Calculation of reactivity changes due to bubble collapse  

International Nuclear Information System (INIS)

[en] 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

1977-06-17

76

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

Energy Technology Data Exchange (ETDEWEB)

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).

Koizumi, Kiyoshi; Uchiyama, Guio; Komatsu, Hideki (Yamanashi Medical Univ., Tamaho (Japan))

1994-11-01

77

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).

1994-01-01

78

Histological and radiological changes in cranial bone in the presence of bone wax.  

UK PubMed Central (United Kingdom)

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 mm(2)) was performed in eight animals. The right side of the cranium 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 mm(2) and 8.16 mm(2). 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.

Raposo-Amaral CE; Almeida AB; Paschoal G; Bueno DF; Vulcano LC; Passos-Bueno MR; Alonso N

2011-08-01

79

Quantifying Changes in the Spatial Structure of Trabecular Bone  

CERN Multimedia

We apply recently introduced measures of complexity for the structural quantfication of distal tibial bone. For the first time, we are able to investigate the temporal structural alteration of trabecular bone. Based on four patients, we show how bone may alter due to temporal immobilisation.

Marwan, Norbert; Felsenberg, Dieter; Saparin, Peter; Kurths, Jürgen

2010-01-01

80

An experimental study on the change of bone mineral metabolism after irradiation  

International Nuclear Information System (INIS)

Irradiation is widely used for the treatment of malignant diseases, and possibly cause the osteoporosis. The bone densitometry and bone scintigraphy and valuable when used to monitor the patients longitudinally to access the progression of osteoporosis and risk of osteoradionecrosis. To evaluate the osteoporosis after irradiation of cobalt-60 gamma ray on the lumbar spines of New Zealand white rabbits, bone densitometry by dual photon absorptiometry and bone scintigraphy were performed weekly. The decrease of bone density began at the first week after irradiation, and were in the nadir at 4-6th week. The osteoblastic activity measured by bone scintigraphy decreased in the first week, and was in the nadir at 4-6th week. The severity of these changes were related to the radiation dose. In conclusion, the osteoporosis before presentation of the osteoradionecrosis can be developed at low dose irradiation and confirmed by bone densitometry, bone scanning, and histopathology.

1988-01-01

 
 
 
 
81

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

UK PubMed Central (United Kingdom)

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.

Smietana MJ; Arruda EM; Faulkner JA; Brooks SV; Larkin LM

2010-12-01

82

[Changes in the reaction of rat bone tissue to hypokinesia after administration of hydroxymethyl aminopropylidene bisphosphonate  

UK PubMed Central (United Kingdom)

During 35-day hypokinesia rat spongy bone in the tibia and vertebrae varied in two phases. The first phase (up to 15 days) was induced by a stress-reaction and the second phase by adaptation to hypokinesia. Under the influence of subcutaneous injections of hydroxydimethyl aminopropylidene biphosphonate (AMOK) at a dose of 0.01 mg/kg/day bone changes disappeared: throughout the study spongy bone mass remained as in controls. AMOK administration at a dose of 5 mg/kg/day 10 days prior to hypokinetic exposure did not eliminate its inhibitory effect although the initial bone mass was 1.5-2 times higher than in the controls. However at the adaptation phase (beginning with day 15) bone mass increased, reaching the baseline. This indicates a decline in bone sensitivity to muscle unloading. It is concluded that AMOK modifies bone responses to various hypokinetic factors.

Shvets VN; Pankova AS; Go'ldovskaia MD; Vnukova ZE

1989-11-01

83

[Changes in the reaction of rat bone tissue to hypokinesia after administration of hydroxymethyl aminopropylidene bisphosphonate].  

Science.gov (United States)

During 35-day hypokinesia rat spongy bone in the tibia and vertebrae varied in two phases. The first phase (up to 15 days) was induced by a stress-reaction and the second phase by adaptation to hypokinesia. Under the influence of subcutaneous injections of hydroxydimethyl aminopropylidene biphosphonate (AMOK) at a dose of 0.01 mg/kg/day bone changes disappeared: throughout the study spongy bone mass remained as in controls. AMOK administration at a dose of 5 mg/kg/day 10 days prior to hypokinetic exposure did not eliminate its inhibitory effect although the initial bone mass was 1.5-2 times higher than in the controls. However at the adaptation phase (beginning with day 15) bone mass increased, reaching the baseline. This indicates a decline in bone sensitivity to muscle unloading. It is concluded that AMOK modifies bone responses to various hypokinetic factors. PMID:2625976

Shvets, V N; Pankova, A S; Go'ldovskaia, M D; Vnukova, Z E

84

[The impact of changing the buccal position of the transported bone on early bone formation after alveolar vertical distraction].  

UK PubMed Central (United Kingdom)

OBJECTIVE: To assess the effects of 1-step method of changing the buccal position of the transported bone after distraction on early bone formation. METHODS: The custom-made bidirectional distraction devices were used. Total of 8 adult mongrel dogs were procured. The bilaterally mandible premolars were extracted. After 1 month, the complete osteotomy was performed and the devices were placed. The gradual distraction was started after 1 week latency at the rate of 1 mm per day, total 6 mm in height was achieved. The 1-step method of changing the buccal position of the transported bone was performed the day after the vertical distraction period in one side of the animals, and the other side as the controlled side. All animals were killed after a 7 days consolidation. The vascular system was stained post mortem carbon ink perfusion to assess possible damages. Quantitative evaluations of bone density were performed with dual-energy X-ray absorptiometry (DEXA), analysis of the ratio of vascular square was conducted in a computer. RESULTS: All animals tolerated the procedures well. After vertical distraction, the tested side can be moved 3 mm in buccal direction. DEXA examination showed that the density of the distracted bone was no statistical difference in both the tested and the controlled side. Vascular damage was not observed, and there was no statistical difference in the ratio of vascular square by analyzing the histological section in computer. CONCLUSION: In some extent, 1-step method of changing the buccal position of the transported bone after distraction can mold the regenerate bone to correct the axial displacement, without endangering early callus formation and vascularization.

Sun M; Lü N; Huang D; Chen S; Yan Y; Zhang L

2011-12-01

85

Bone changes and fracture related to menstrual cycles and ovulation.  

Science.gov (United States)

Women's menstrual cycles and bone remodeling are linked in part by their co-dependency on the stress- and resource-associated variables that govern both of their cyclical natures. Therefore, it is not surprising that evolution has resulted in the same signaling molecules and pathways that regulate normal ovarian function to be involved in bone remodeling and turnover. This review will first provide an overview of the normal menstrual cycle, its modification by age and ovulatory disturbances, and how it parallels bone remodeling. Epidemiological and clinical evidence will be presented that link bone remodeling, strength, and fractures with women's history of reproductive and menstrual cycle characteristics. This combined evidence will then be presented alongside a synthesis of current concepts derived from basic science investigations focused on understanding the molecular mechanisms underlying the influence of ovarian factors on bone physiology. Osteoporosis is a significant source of morbidity for older women. The data presented in this review suggest that a woman's reproductive cycle and ovulatory characteristics foreshadow the future health of her bones. More importantly, identifying the key mechanisms underlying reproductive and bone health would not only provide essential preventative strategies, but may also uncover attractive targets for the treatment of osteoporosis. PMID:21175412

Kalyan, Shirin; Prior, Jerilynn C

2010-01-01

86

Changes in bone mineral content following tibia shaft fractures.  

UK PubMed Central (United Kingdom)

The bone mineral content of the upper ends of the tibia and the fibula was measured in 27 patients with tibia shaft fracture. The bone mineral decreased rapidly after fracture, the loss continuing for about 5 months. Later, towards the end of the first year after the injury, there was a slow restoration of mineral but no return to initial values in most instances. Although the average maximum loss was approximately 45%, only 25% of the initial bone mineral was missing after one year.

Andersson SM; Nilsson BE

1979-10-01

87

Changes in bone mineral content following tibia shaft fractures.  

Science.gov (United States)

The bone mineral content of the upper ends of the tibia and the fibula was measured in 27 patients with tibia shaft fracture. The bone mineral decreased rapidly after fracture, the loss continuing for about 5 months. Later, towards the end of the first year after the injury, there was a slow restoration of mineral but no return to initial values in most instances. Although the average maximum loss was approximately 45%, only 25% of the initial bone mineral was missing after one year. PMID:535229

Andersson, S M; Nilsson, B E

1979-10-01

88

Smaller, weaker, and less stiff bones evolve from changes in subsistence strategy.  

UK PubMed Central (United Kingdom)

UNLABELLED: We propose a computational model with which to examine the evolution of bone. Our results indicate that changes in subsistence strategy have influenced the evolution of bone growth and mechanoregulation, and predict that bone size, stiffness, and structural strength may decrease in future generations, bringing increased risk of fracture and prevalence of osteoporosis. INTRODUCTION: Archeological data suggest that bone size and strength have decreased over evolution. We hypothesize that changing evolutionary pressures and levels of physical activity, both arising from changes in subsistence strategy, have affected the evolution of bone. We propose a computational model with which to examine the evolution of bone growth and mechanoregulation due to the transitions from hunter-gatherer to agricultural to modern lifestyles. METHODS: The evolution of genes governing growth and mechanoregulation in a population of bones is simulated, where each individual is represented by a 2-D bone cross-section. Genetic variability is assumed to modulate growth through mechanoregulatory factors that direct periosteal expansion, endosteal expansion/infilling, and ash content accretion in response to strains incurred during walking. RESULTS: The model predicts decreases in cortical area and section modulus (a measure of structural strength) and increases in maximum compressive strain over the course of the simulation, meaning evolution of smaller, less strong, and less stiff bones is predicted for the population average. The model predicts small but continued decreases in size, strength, and stiffness in modern populations, despite the absence of a strong evolutionary advantage to efficient bones during this phase. CONCLUSION: In conclusion, our results show that changing loading regimes and evolutionary pressures may have influenced the evolution of bone growth and mechanoregulation, and predict that bone size and strength may continue to decrease in future generations, bringing increased risk of fracture and prevalence of osteoporosis.

Nowlan NC; Jepsen KJ; Morgan EF

2011-06-01

89

Main regularities in the phase of the contrast agent elimination from reactively changed lymph nodes  

International Nuclear Information System (INIS)

[en] Results of studying the phase of elimination of oil contrast agents from 236 reactively changed lymph nodes in 71 patients with cervix uteri and corpus uteri carcinoma are given. It is shown that the duration of adenitis reactivity and especially its abatement depend on the rate of malignant tumour regression. It is established that a decrease in the size of the nodes and normalization of their structure are the main roentgenological signs of reactive adenitis abatement. The reactively changed lymph nodes decrease in their size along the length of the entire phase of elimination, and by the 13-14 months of observation their size comprises less than 1/4 of initial one at the phase of accumulation. Recurrent reactive adenitis in the regional lymph nodes in patients with cervix and corpus uteri carcinoma was observed in 10% of the cases. The most optimal time for the studies of the condition of reactively changed lymph nodes are 2, 7, 11 and 15-month phases of elimination

1980-01-01

90

Evaluation of bone changes in the temporomandibular joint using cone beam CT  

Science.gov (United States)

Objective The aim of this study was to assess bone changes and mobility in temporomandibular joints (TMJs) using cone beam CT (CBCT) in a population sample in Recife, PE, Brazil. Methods The TMJ images of patients treated by a radiologist at a private dental radiology service over a period of 1 year were retrieved from the computer database and assessed using a computer with a 21-inch monitor and the iCAT Cone Beam 3D Dental Imaging System Workstation program (Imaging Sciences International, Hatfield, PA). The Pearson ?2 test was used to analyse the differences in percentage of bone changes among the categories of mobility (p ? 0.05). The McNemar test was used to compare the presence of bone changes in TMJs on the right and left sides (p ? 0.05). Results An adjusted logistic regression model was used to assess the effect of age and gender on the occurrence of bone changes (p ? 0.05). Bone changes were present in 227 (71%) patients. Age group and gender showed a statistically significant association with presence of bone changes (p ? 0.05). There was no significant difference between the right and left sides (p = 0.556) and in condylar mobility (p = 0.925) with regard to the presence of degenerative bone changes. Conclusions There is a high prevalence of degenerative bone alteration in TMJs, which is more frequent in women and mostly located in the condyle. The prevalence of degenerative bone changes increases with age. There is no correlation between condylar mobility and the presence of degenerative bony changes in TMJs.

dos Anjos Pontual, ML; Freire, JSL; Barbosa, JMN; Frazao, MAG; dos Anjos Pontual, A; Fonseca da Silveira, MM

2012-01-01

91

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

92

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

UK PubMed Central (United Kingdom)

PURPOSE: 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 ?g/day subcutaneous) who had (99m)Tc-methylene diphosphonate (MDP) bone scans (baseline, 3 and 18 months, then after 6 months off therapy). METHODS: Women were injected with 600 MBq (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 (99m)Tc-MDP skeletal plasma clearance (K(bone)). Regional K(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. RESULTS: 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(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(bone) changes were three times larger than other sites. After 6 months off therapy, all K(bone) and BTM values returned towards baseline. CONCLUSION: The increased (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 (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.

Moore AE; Blake GM; Taylor KA; Ruff VA; Rana AE; Wan X; Fogelman I

2012-02-01

93

Founders lecture 2007. Metabolic bone disease: what has changed in 30 years?  

Energy Technology Data Exchange (ETDEWEB)

To provide an update on imaging of metabolic bone disease based on new developments, findings, and changing practices over the past 30 years. Literature review of osteoporosis, osteomalacia, renal osteodystrophy, Paget's disease, bisphosphonates, with an emphasis on imaging. Cited references and pertinent findings. Significant developments have occurred in the imaging of metabolic bone disease over the past 30 years. (orig.)

Sundaram, Murali [Cleveland Clinic, Diagnostic Radiology, MSK, Cleveland, OH (United States)

2009-09-15

94

Founders lecture 2007. Metabolic bone disease: what has changed in 30 years?  

International Nuclear Information System (INIS)

To provide an update on imaging of metabolic bone disease based on new developments, findings, and changing practices over the past 30 years. Literature review of osteoporosis, osteomalacia, renal osteodystrophy, Paget's disease, bisphosphonates, with an emphasis on imaging. Cited references and pertinent findings. Significant developments have occurred in the imaging of metabolic bone disease over the past 30 years. (orig.)

2009-01-01

95

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

Energy Technology Data Exchange (ETDEWEB)

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).

Soeballe, K.; Hansen, E.S. (Aarhus Univ. (Denmark). Biomechanics Lab. Aarhus Univ. (Denmark). Inst. of Experimental Clinical Research); Pedersen, C.M. (Aarhus Kommunehospital (Denmark). Dept. of Diagnostic Radiology); Odgaard, A.; Hvid, I.; Buenger, C. (Aarhus Univ. (Denmark). Biomechanics Lab.); Juhl, G.I. (Aarhus Univ. (Denmark). Inst. of Experimental Clinical Research); Rasmussen, H.B. (Aarhus Amtssygehus (Denmark). Inst. of Pathology)

1991-07-01

96

Changes in navicular bone (os sesamoideum distale) shape in horses as a result of pathological alterations.  

UK PubMed Central (United Kingdom)

The main aim of the study was to compare the shape of navicular bones classified as normal and pathologically changed. A comparison of metric features of the navicular bone between different types of horses and associating the examined parameters to the size of the middle and distal phalanges was an additional aspect of the study. The material comprised 53 horses of various breeds which were divided into three types. Through anatomical examinations it was concluded that as many as 30 navicular bones were normal, while 23 were found to present pathological changes. The following methods of statistical analysis were used: Levene's test, one-way ANOVA, T-test, LSD test and Pearson correlation. The shape of the navicular bone was described by seven indices developed for this purpose. From among them, three show statistically higher values in the affected bones compared to the healthy ones. The main result of the study is that navicular bones with defects are relatively thicker and have a higher flexor surface and a higher articular surface for the joint with the middle phalanx. Therefore our hypothesis is that the occurrence of pathological changes of the navicular bone is preceded by an increase in the thickness and height of this bone. Adverse changes occur only in the subsequent stage of the process. The study also revealed the interrelations between the phalanges and some metric features of the navicular bone. There were strong correlations between the breadth of the middle and distal phalanx, and the breadth and thickness of the navicular bone. Also, the height of the flexor surface of the navicular bone is strongly correlated with the breadth of the phalanges.

Komosa M; Purzyc H; Fraackowiak H

2013-01-01

97

The effect of bone morphometric changes on orthodontic tooth movement in an osteoporotic animal model.  

Science.gov (United States)

ABSTRACT Objective: To elucidate the effect of bone morphometric changes on orthodontic tooth movement (OTM) in zoledronic acid-treated ovariectomized rats. Materials and Methods: Twenty-one 10-week-old female Wistar rats were divided into ovariectomy (OVX), OVX with zoledronic acid administration (OVX + ZOL), and sham operation (control) groups. Two weeks after OVX, ZOL administration was initiated. Twelve weeks after OVX, a nickel-titanium closed-coil spring of 25-g force was applied mesially to the maxillary left first molar. In vivo micro-computed tomography (CT) of the left proximal tibia was performed for bone morphometric analysis every 2 weeks after OVX. In addition, OTM was investigated using micro-CT at 0, 12, and 14 weeks after OVX. Results: There were significant differences in the bone mineral content (BMC), bone volume (BV), BMC to tissue volume ratio (BMC/TV), and BV to TV ratio of trabecular bone between the control and OVX groups and also between the OVX + ZOL and OVX groups. In the OVX + ZOL group, increased BMC and BV in the cortical bone and increased bone mineral density (BMD) in the trabecular bone were observed. Interestingly, OTM in the OVX group was almost two times more than that in the control and OVX + ZOL groups. Moreover, OTM was correlated with BMD, BMC, BV, and BMC/TV in the trabecular bone. Conclusions: OVX accelerated OTM, while ZOL suppressed it. OTM demonstrated a significant negative relationship with trabecular bone mass. PMID:23445276

Hashimoto, Megumi; Hotokezaka, Hitoshi; Sirisoontorn, Irin; Nakano, Takako; Arita, Kotaro; Tanaka, Motohiro; Yoshida, Noriaki

2013-02-27

98

Reactivity change measurements on plutonium-uranium fuel elements in hector experimental techniques and results  

International Nuclear Information System (INIS)

The techniques used in making reactivity change measurements on HECTOR are described and discussed. Pile period measurements were used in the majority of oases, though the pile oscillator technique was used occasionally. These two methods are compared. Flux determinations were made in the vicinity of the fuel element samples using manganese foils, and the techniques used are described and an error assessment made. Results of both reactivity change and flux measurements on 1.2 in. diameter uranium and plutonium-uranium alloy fuel elements are presented, these measurements being carried out in a variety of graphite moderated lattices at temperatures up to 450 deg. C. (author)

1964-01-01

99

Changes in Bone Turnover Markers and Bone Mass with Reducing Levels of Jumping Exercise Regimens in Female Rats  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose:To date,little is known about the effects of a reduced level of jumping exercise regimens on bone turnover markers and mass. This study investigates the effects of different jumping exercise regimens with varying exercise loads on serum bone turnover markers and bone mass in female rats.Methods:A total of 144 female rats aged 12 weeks, were divided into 12 groups as follows: no exercise for 8 (8S) or 32 weeks (32S), or 8 weeks of standard training program (8STP) consisting of 200 jumps per week (200J/w), given at 40 jumps per day (40J/d) for 5 days per week (5d/w) (8STP24E), followed by 24 weeks of exercise at loads of either 10J/d or 20J/d or 40J/d, for either 5d/w, or 3d/w, or 1d/w. Serum osteocalcin, alkaline phosphatase, C-terminal telopeptideof type 1 collagen (1CTP) concentrations, and tibial fat free dry weight were measured.Results: Tibial mass was significantly higher in 8STP than 8S. No changes were evident in serum markers of bone turnover parameters after 8STP. Significant increases in tibial mass were observed in rats that continued to exercise at workloads of 30J/w and above after 8STP. Serum alkaline phosphatase concentrations increase whereas serum 1CTP concentrations decrease in rats given workloads of 40J/w and above.Conclusions: It appears, an exercise load of 30J/w, i.e. 10J/d for 3d/w,was the minimum level of continuous exercise load that was required to maintain the 8STP-induced bone gains. In addition, significant increases in bone mass in young rats following 8STP might not always be reflected by changes in serum levels of osteocalcin, alkaline phosphatase and 1CTP.

Foong Kiew Ooi; Rabindarjeet Singh; Harbindar Jeet Singh

2012-01-01

100

Treatment of Radiation Induced Biological Changes by Bone Marrow Transplantation  

International Nuclear Information System (INIS)

[en] 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

1999-01-01

 
 
 
 
101

Stability changes after cryosurgery in long tubular bones in correlation to histological results: an animal trial.  

UK PubMed Central (United Kingdom)

STUDY QUESTION: Pathologic bone fractures in cryosurgery of bone tumors have been described in literature. This study utilizing a sheep model should prove the possible reduction of potential fracture while using a new miniature cryoprobe minimizing tissue damage and providing accurate control of the ablation process. Furthermore, postoperative histological changes should be investigated and the results correlated with the stability trials. METHODS: In 24 sheep, ablation of the femur and the tibial bone on one side was carried out. Ablation of the right femur was limited to an area of 2 cm(2) with single cortical bone, whereas at the left tibia the whole proximal tibial plateau was included. The other side served as a control entity without cryoablation. After a period of 2, 4, and 6 months postoperative investigation of bending resistance of the femoral bone and of compression resistance of the tibial bone as well as histological findings were done in eight animals each. RESULTS: After 2 months there was a significant difference (P < 0.05) regarding compression resistance between the treated and the contralateral tibia, whereas the bending resistance in the treated femur was slightly lower than on the contralateral side. After 4 and 6 months the cryo-treated part showed a tendency towards weakness. Histological findings showed bone necrosis with slight beginning repair after 2 months. Four and six months later, bone necrosis still existed with increasing development of woven bone and conversion into lamellar bone. DISCUSSION: A thorough control of the freezing process and the low iatrogenous weakening of the bone due to placing the probe when modern miniature cryoprobes are used can minimize the risk of pathological postoperative fractures. However, at least 2 months after operation there is histological proof of bone healing with appropriate reduction of bone stability, which should be considered for the clinical application of this new technique.

Popken F; Michael JW; Zarghooni K; Sobottke R; Kasper HU; Blaecker D; Niehoff A; Emrich F; Eysel P

2009-06-01

102

Radiographic bone changes in multibacillary leprosy patients in Aburof mission clinic  

International Nuclear Information System (INIS)

[en] 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)

1996-01-01

103

[Seasonal changes in bronchial reactivity in pollinosis patients].  

UK PubMed Central (United Kingdom)

THE AIM OF THE STUDY: To evaluate seasonal changes in bronchial hyperreactivity (BHR) in patients suffering from pollinosis, sensitive to Ryegrass engl. MATERIAL AND METHODS: The studies were carried out on 26 patients and 20 healthy subjects. All the patients had a history of seasonal allergic rhinitis. The following measurements were performed outside and during the pollen season: bronchial provocation test (BPT) with metacholine and 4.5% NaCl, serum concentration of specific and total IgE. RESULTS: Outside the pollen season additionally the BPT with Ryegrass engl. allergen was performed and 88% of the pollinosis patients had positive result of the test. After 4.5% NaCl bronchial challenge positive results had 2 out of 26 patients outside the season, and 3 during the season. Bronchial hyperreactivity to metacholine (PC20 < 8 mg/ml) were observed in 4/26 (15.4%) persons outside the season and in 7 (26.9) during the season. The healthy subjects had no bronchoconstriction neither after metacholine or 4.5% NaCl. During the pollen season the increase in serum concentration of tIgE and sIgE was observed only in pollinosis patient. CONCLUSIONS: There was not found a correlation between BHR to the allergen and serum total IgE nor specific IgE concentration.

Siergiejko Z; Swiebocka E; Siergiejko G; Hofman J

2005-01-01

104

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

Energy Technology Data Exchange (ETDEWEB)

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

105

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

Directory of Open Access Journals (Sweden)

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.

Kotaro Tanimoto; Yuki Tanne; Keisuke Sumi; Naoto Hirose; Nobuhiko Kawai; Eiji Tanaka; Kazuo Tanne

2013-01-01

106

Bacteria-reactive immune response may induce RANKL-expressing T cells in the mouse periapical bone loss lesion.  

UK PubMed Central (United Kingdom)

INTRODUCTION: The present study investigated whether bacteria infecting the root canal can activate any infiltrating T cells to produce receptor activator of nuclear factor kappa B (NF-?B) ligand (RANKL). METHODS: Using a mouse model of periapical lesion induced by artificial dental pulp exposure, the presence of RANKL-positive T cells and osteoclasts in the periapical lesion was examined by an immunohistochemical approach. The bacteria colonizing the exposed root canal were identified by 16S ribosomal RNA (rRNA) sequence analysis. The isolated endodontic bacteria were further immunized to normal mice, and soluble activator of NF-?B ligand (sRANKL) production by the T cells isolated from the immunized mice was evaluated by ex vivo culture system. RESULTS: RANKL-positive T cells along with TRAP+ osteoclasts were identified in periapical bone resorption lesions. The gram-negative bacterium Pasteurella pnumotropica, which was most frequently detected from the root canal of exposed pulp, showed remarkably elevated serum immunoglobulin G (IgG)-antibody response in pulp-exposed mice compared with control nontreated mice. Immunization of mice with P. pneumotropica induced not only serum IgG-antibody but also primed bacteria-reactive T cells that produced sRANKL in response to ex vivo exposure to P. pneumotropica. CONCLUSIONS: T cells infiltrating the periapical region express RANKL, and the endodontic bacteria colonizing the root canal appear to induce RANKL expression from bacteria-reactive T cells, suggesting the possible pathogenic engagement of the immune response to endodontic bacteria in the context of developing bone resorptive periapical lesions.

Silva MJ; Kajiya M; AlShwaimi E; Sasaki H; Hong J; Ok P; Rezende TM; Pagonis TC; White RR; Paster BJ; Stashenko P; Kawai T

2012-03-01

107

Changes in bone mineral density are correlated with bone markers and reductions in hot flush severity in postmenopausal women treated with bazedoxifene/conjugated estrogens.  

UK PubMed Central (United Kingdom)

OBJECTIVE: A post hoc exploratory analysis was conducted to examine correlations between changes in bone density, bone markers, and hot flushes after the treatment of postmenopausal women with bazedoxifene (BZA)/conjugated estrogens (CE). METHODS: In a 2-year phase 3 study, 3,397 postmenopausal women were randomized to BZA 10 mg/CE 0.45 mg, BZA 20 mg/CE 0.45 mg, BZA 40 mg/CE 0.45 mg, BZA 10 mg/CE 0.625 mg, BZA 20 mg/CE 0.625 mg, BZA 40 mg/CE 0.625 mg, raloxifene 60 mg, or placebo. In this analysis, bone density changes at 2 years were compared with baseline levels of the bone markers serum C-telopeptide and osteocalcin. Correlations between changes in bone density and changes in 12-week hot flush composite scores in symptomatic women were also analyzed. RESULTS: Treatment with BZA 20 mg/CE 0.45 mg or BZA 20 mg/CE 0.625 mg increased lumbar spine bone density more in women with higher bone resorption and formation, categorized by baseline levels of C-telopeptide and osteocalcin (P < 0.001, both BZA/CE doses). With placebo, larger decreases in lumbar spine bone density were seen in the highest tertile of serum C-telopeptide. There was no correlation between changes in total hip bone density and baseline bone markers. There were significant correlations between percent change in hot flush score at week 12 and percent changes in lumbar spine (r = -0.31, P = 0.006) and total hip (r = -0.23, P = 0.044) bone densities at month 24. CONCLUSIONS: With 2-year BZA/CE treatment, women with larger increases in lumbar spine and total hip densities also have higher baseline bone markers. Early reductions in hot flush score (12 wk) are predictive of long-term increases in bone density (24 mo).

Gallagher JC; Shi H; Mirkin S; Chines AA

2013-04-01

108

Study of the effects of progressive changes in alkoxysilane structure on sol-gel reactivity.  

UK PubMed Central (United Kingdom)

Effects of the structure of an alkoxysilane on the early reaction kinetics of sol-gel polymerization are investigated in basic and acidic conditions. Six silanes, including tetraethoxysilane (TEOS), tetramethoxysilane (TMOS), methyltrimethoxysilane (MTMS), bis(trimethoxysilyl)ethane (BTMSE), bis(trimethoxysilyl)hexane (BTMSH), and bis(trimethoxysilylpropyl)amine (BTMSPA), are selected to examine the effects of progressive changes in the silane's structure. In basic conditions, reactivities of the silanes follow the pairwise trends TEOS << TMOS, TMOS > MTMS, MTMS < BTMSE, BTMSE >> BTMSH, and BTMSH << BTMSPA. Hydrolysis rate coefficients of BTMSE, TMOS, MTMS, and BTMSPA are similar in value and are almost one order of magnitude larger than the coefficients of BTMSH and TEOS. In acidic conditions, the pairwise reactivity trends are TEOS approximately TMOS, TMOS < MTMS, MTMS > BTMSE, BTMSE >> BTMSH, and BTMSH > BTMSPA. The condensation rate coefficients of BTMSH and BTMPA are much smaller than the others. Theses relationships can be explained mainly on the basis of the expected inductive and steric factors of the silanes. Bulky organics attached to the silane lead to low reactivity in both acidic and basic conditions. A high electron density at silicon leads to a low reactivity in basic conditions but a high reactivity in acidic conditions (pH approximately 2.3). Only BTMSPA in basic conditions defies these trends, possibly because of the effects of solvation near the reactive silicon site.

Tan B; Rankin SE

2006-11-01

109

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

2002-01-01

110

Longitudinal changes in lumbar bone mineral density distribution may increase the risk of wedge fractures.  

UK PubMed Central (United Kingdom)

BACKGROUND: Trabecular bone strength diminishes as a result of osteoporosis and altered biomechanical loading at the vertebral and spinal levels. The spine consists of the anterior, middle and posterior columns and the load supported by the anterior and middle columns will differ across different regions of the spine. Stress shielding of the anterior column can contribute to bone loss and increase the risk of wedge fracture. There is a lack of quantitative data related to regional spinal bone mineral density distribution over time. We hypothesize that there is an increase in the posterior-to-anterior vertebral body bone mineral density ratio and a decrease in whole-body bone mineral density over time. METHODS: Bone mineral density was measured in 33 subjects using quantitative computed tomography scans for L1-L3 vertebrae, region (anterior and posterior vertebral body), and time (baseline and 6 years after). FINDINGS: Lumbar bone mineral density decreased significantly (?: ~15%) from baseline to the 6th year visit. Individual vertebra differences over time (L1: ~14%, L2: ~14%, L3: ~17%) showed statistical significance. Anterior bone mineral density change was significantly greater than in the posterior vertebral body region (? anterior: ~18%; ? posterior: ~13%). Posterior-to-anterior bone mineral density ratio was significantly greater in the 6th year compared to baseline values (mean (SD), 1.33 (0.2) vs. 1.23 (0.1)). INTERPRETATION: This study provides longitudinal quantitative measurement of bone mineral density in vertebrae as well as regional changes in the anterior and posterior regions. Understanding bone mineral density distribution over time may help to decrease the risk of wedge fractures if interventions can be developed to bring spine loading to its normal state.

Giambini H; Khosla S; Nassr A; Zhao C; An KN

2013-01-01

111

Relationships between changes in bone mineral density or bone turnover markers and vertebral fracture incidence in patients treated with bazedoxifene.  

Science.gov (United States)

We analyzed the relationships between bone mineral density (BMD) or bone turnover marker (BTM) changes and vertebral fracture incidence in women treated with bazedoxifene using a post hoc analysis from a 3-year randomized, placebo-controlled study evaluating the effect of bazedoxifene (20 or 40 mg) on fracture risk reduction. BMD was assessed at baseline and every 6 months for 3 years. Osteocalcin and C-telopeptide of type I collagen were assessed at baseline and at 3, 12, and 36 months. Vertebral fractures were assessed with a semiquantitative visual assessment. Data were available for 5,244 women, of whom 3,476 were treated with bazedoxifene. Using a logistic regression analysis and the classical Li approach, the proportion of fracture incidence explained by BMD change after 3 years of bazedoxifene treatment was 29 % for the total hip and 44 % for the femoral neck. The proportion of treatment explained by lumbar BMD change could not be quantified accurately because of the significant interaction between treatment and change in BMD. With the same model, the 12-month BTM changes explained up to 29 % of the fracture risk reduction observed with the two forms of bazedoxifene. In women treated with bazedoxifene, changes in femoral neck BMD, hip BMD, or BTMs explained a moderate proportion of the fracture risk reduction observed during the 3 years of follow-up. However, BMD or BTM changes cannot be recommended for individual monitoring of women treated with bazedoxifene. PMID:22945761

Bruyère, Olivier; Detilleux, Johann; Chines, Arkadi; Reginster, Jean-Yves

2012-07-28

112

Relationships between changes in bone mineral density or bone turnover markers and vertebral fracture incidence in patients treated with bazedoxifene.  

UK PubMed Central (United Kingdom)

We analyzed the relationships between bone mineral density (BMD) or bone turnover marker (BTM) changes and vertebral fracture incidence in women treated with bazedoxifene using a post hoc analysis from a 3-year randomized, placebo-controlled study evaluating the effect of bazedoxifene (20 or 40 mg) on fracture risk reduction. BMD was assessed at baseline and every 6 months for 3 years. Osteocalcin and C-telopeptide of type I collagen were assessed at baseline and at 3, 12, and 36 months. Vertebral fractures were assessed with a semiquantitative visual assessment. Data were available for 5,244 women, of whom 3,476 were treated with bazedoxifene. Using a logistic regression analysis and the classical Li approach, the proportion of fracture incidence explained by BMD change after 3 years of bazedoxifene treatment was 29 % for the total hip and 44 % for the femoral neck. The proportion of treatment explained by lumbar BMD change could not be quantified accurately because of the significant interaction between treatment and change in BMD. With the same model, the 12-month BTM changes explained up to 29 % of the fracture risk reduction observed with the two forms of bazedoxifene. In women treated with bazedoxifene, changes in femoral neck BMD, hip BMD, or BTMs explained a moderate proportion of the fracture risk reduction observed during the 3 years of follow-up. However, BMD or BTM changes cannot be recommended for individual monitoring of women treated with bazedoxifene.

Bruyère O; Detilleux J; Chines A; Reginster JY

2012-10-01

113

Effect of changing the BN-600 core composition on the sodium void reactivity coefficient  

International Nuclear Information System (INIS)

[en] Changes in the BN-600 reactor core configuration affecting the value of sodium void reactivity factor (SVRF) are analyzed. The method of preparation of the calculation models and SVRF calculated results for various configurations of the core ate provided. The calculated results suggest practicability of the developed method employment for SVRF identification using the SYNTES code, if the BN-600 reactor core configuration is to be changed[ru] ??? ?????? ??????? ????????? ??????? ???????? ???? ???????? ??-600 ?? ???????? ?????????? ?????????? ??????? ???????????? (????). ????????? ???????? ?????????? ???????? ??????? ? ?????????? ???????? ???? ??? ?????? ???????? ???????? ????. ?????????? ???????? ?????????? ??????????? ????????????? ????????????? ???????? ??????????? ???? ?? ????????? SYNTES ??? ????????? ??????? ???????? ???? ???????? ??-600

2005-01-01

114

Pore structure and reactivity changes in hot coal gas desulfurization sorbents  

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

115

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

Energy Technology Data Exchange (ETDEWEB)

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).

Racz, A. (CRIP-Atomic Energy Research Inst., Budapest (Hungary). Dept. of Applied Reactor Physics)

1992-09-01

116

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).

1992-01-01

117

Two models of early weaning decreases bone structure by different changes in hormonal regulation of bone metabolism in neonate rat.  

Science.gov (United States)

During the last decade a great concern has developed for determining what factors influence bone mineral accretion in healthy children. Mother's milk represents the primary source of calcium and other nutrients in the neonate. The development of bone and adipose tissue has common origins. Since early weaning decreases adipogenesis in neonate, our aim was to evaluate bone metabolism in 2 models of early weaning (EW) in neonate rats. Lactating rats were separated into 3 groups: control: pups had free access to milk; MEW: dams were involved with a bandage mechanically (M) interrupting lactation in the last 3 days; and PEW: dams were pharmacologically (P) treated to block prolactin (0.5 mg bromocryptine/twice a day) 3 days before standard weaning. Significant difference had pcontent (-30% and -32%), bone area (-28% and -30%), serum osteocalcin (-20% and -55%), and higher C-terminal cross-linked telopeptide of type I collagen (CTX-I) (1.3 and 1.1-fold increase). However, serum ionized calcium was lower only in MEW pups (-34%), 25-hydroxyvitamin D was higher (1.4-fold increase), and PTH was lower (-26%) only in PEW group. The present study shows that both early weaning models leads to an impairment of osteogenesis associated with lower adipogenesis by different mechanisms, involving mainly changes in vitamin D and PTH. PMID:23264036

de Albuquerque Maia, L; Lisboa, P C; de Oliveira, E; da Silva Lima, N; da Costa, C A S; de Moura, E G

2012-12-21

118

Allometric secular change in the long bones from the 1800s to the present.  

UK PubMed Central (United Kingdom)

Allometric secular changes in the six long limb bones for White and Black males from the mid 1800s to the present are examined. Long bone lengths are available from the Terry collection and WWII casualties. We conducted two types of analysis to reveal secular changes. First, allometry scaling coefficients were derived by regressing log bone length onto log stature. These showed that the femur, tibia and fibula were positively allometric with stature, while the humerus, radius and ulna were isometric. The lower limb bones were more positively allometric in the WWII sample than in the Terry sample. Second, secular changes in length of femur and tibia and in the tibia/femur ratio were evaluated, using modern forensic cases in addition to the Terry and WWII samples. This analysis shows that secular increase in lower limb bone length is accompanied by relatively longer tibiae. Secular changes in proportion may render stature formulae based on nineteenth century samples, such as the Terry collection, inappropriate for modern forensic cases. The positive allometry of the lower limb bones argues against using simple femur/stature ratio, which assumes constant proportionality, as an alternative to regression equations.

Meadows L; Jantz RL

1995-09-01

119

The study on changes of bone mineral content of mandible by quantitative computed tomography  

International Nuclear Information System (INIS)

A method to measure bone mineral of mandible has not been established. The bone mineral content (BMC) of the mandible with single energy quantitative computed tomography (SEQCT), which was compared with that of the spine, was discussed. The subjects were 104 healthy persons (54 males and 50 females, age range: 21-69) and 33 patients of mandibular atrophy (10 males and 23 females, age range: 46-87). The BMC changes of the mandible differed according to sex. In males BMC of trabecular bone and cortical bone decreased slightly after 40 and 30 years of age respectively. In females, BMC decreased consistently during menopause. BMC of the spine tended to decrease with aging, especially in females. In males having mandibular atrophy, the BMC of trabecular bone of the mandible decreased, and that of cortical bone of the mandible increased with aging. In females having atrophy, the BMC of trabecular bone and cortical bone of the mandible decreased with aging. The BMC of the mandible was correlated with the length of the denture-wearing time in males. In females, it appears that the BMC of the mandible participates in estrogen deficiency like the BMC of the spine. From the above, measurement of the BMC of the mandible by SEQCT was considered to be very useful for grasping the severity and progressive rate, and other conditions of alveolar ridge atrophy and determining the remedial course. (author)

1996-01-01

120

Effect of eicosapentaenoic acid on bone changes due to methylprednisolone in rats.  

UK PubMed Central (United Kingdom)

The present study was conducted to investigate the effects of eicosapentaenoic acid on glucocorticoid-induced bone changes in rats, and to compare them with those of alendronate. Thirty six male Wistar rats, 2.5 months of age, were divided into six groups (n = 6 each) and treated with 0.9% NaCl (control), methylprednisolone 7 mg/kg, once a week subcutaneously, methylprednisolone + alendronate 20 microg/kg, twice a week subcutaneously and methylprednisolone + 80 or 160 or 320 mg/kg eicosapentaenoic acid, per day orally, for 6 weeks. At the end of the experiment, serum and urinary parameters of bone metabolism determined and bone histomorphometric analyses performed on cancellous bone of femoral epiphysis and metaphysis and cortical bone of tibial diaphysis. There were no significant differences in serum and urinary parameters among groups. Decrease of epiphyseal and metaphyseal trabecular width, epiphyseal bone area/tissue area and increase of epiphyseal trabecular separation observed in the methylprednisolone group compared to control. Alendronate restored all of these parameters except metaphyseal trabecular width, which increased significantly by eicosapentaenoic acid at the doses of 80 and 160 mg/kg. Effects of alendronate and 160 mg/kg eicosapentaenoic acid on bone area/tissue area, alendronate and eicosapentaenoic acid at the doses of 80 and 160 mg/kg on trabecular separation and alendronate and eicosapentaenoic acid at doses of 160 and 320 mg/kg on epiphyseal trabecular width were statistically similar. Methylprednisolone did not significantly change cortical bone parameters including cortical width and marrow area/cortical area. Eicosapentaenoic acid, especially, at the dose of 160 mg/kg exerts beneficial effects on methylprednisolone-induced bone changes in rats; these effects are similar or sometimes even better than alendronate.

Shomali T; Rezaian M; Rassouli A; Asadi F

2009-07-01

 
 
 
 
121

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

Directory of Open Access Journals (Sweden)

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.; Yashchenko A.M.

2007-01-01

122

[Bone mineral density changes in coal workers' pneumoconiosis in Two and Triple stages with increasing ages].  

UK PubMed Central (United Kingdom)

OBJECTIVE: To observe the bone mineral density changes in coal workers' pneumoconiosis in Two and Triple stages with increasing ages. METHODS: Chose 70 cases of coal workers pneumoconiosis in Two and Triple stages in Jincheng Coal Mining Group, all of workers were male, of 55-years old-80 years old, an average of 67 years old. 10 years of ages to grouping, whole body bone mineral densities were measured by body dual-energy X-ray absorptiometry. We analyzed the BMD changes bone loss, osteoporosis occurrence. RESULTS: Chest bone, pelvis, spine bone mineral densities of coal workers pneumoconiosis in Two and Triple stages were significantly decreased. We found that the rate of Pelvic BMD decline of coal workers' pneumoconiosis patients in Two stage was significantly faster after 65 years of age. In Different age groups of coal workers' pneumoconiosis patients in Two and Triple stages, incidence of bone loss and osteoporosis were significantly increased. CONCLUSION: With the age increasing, Coal workers' pneumoconiosis in Two and Triple stages significantly accelerated the speed of the rate of BMD decline. This phenomenon was most obvious in the chest bone, pelvis, and spine.

Li HX; Zhai PY; Yan JF

2012-08-01

123

Does whole-body vibration with alternative tilting increase bone mineral density and change bone metabolism in senior people?  

UK PubMed Central (United Kingdom)

BACKGROUND AND AIMS: Whole-body vibration (WBV) presents as osteogenic in animal models and young patients, but the effect remains unclear in senior people. The use of alternative tilting during WBV to ameliorate bone mass and bone metabolism, particularly in senior people, has not previously been reported. This study assessed changes in bone mineral density (BMD) and bone metabolism in senior people after six-month treatment of whole-body vibration with alternative tilting (WBVAT). METHODS: Fifty-three senior people (11M/42F, >65 yrs, mean age 77) and 15 adults (4M/11F, 50-60 yrs, mean age 53) were enrolled and assigned randomly to WBVAT (senior: n=27; adult: n=7) and control groups (senior: n=26; adult: n=7), respectively. The WBVAT groups were subjected to vertical vibration (0.5-0.8 g, 45-55 Hz) and alternative tilting (2° tilting angle or 8 mm displacement at 0.4 Hz) 20 minutes per day, 3 days a week, for 6 months. BMD in the lumbar spine and femoral neck was measured at 0, 3 and 6 months, respectively, as well as biochemical markers of bone metabolism, including serum calcium, phosphorus, alkaline phosphatase (ALP), osteocalcin and tartrate resistance acid phosphatase at 0, 1, 3 and 6 months, respectively. RESULTS: After 6-month WBVAT treatment, BMD in the lumbar spine and femoral neck increased significantly by 2.52% and 3.22% for senior people, and 1.63% and 2.05% for adults, respectively. The 6-month WBVAT treatment increased BMD in the senior people, both with and without osteoporosis (OP) and in both men and women, but led to a BMD gain greater in people with OP (p<0.01) and women (p<0.01), respectively. The serum ALP level increased significantly by a net 24.4% in seniors after WBVAT treatment at 3 months; other biochemical markers showed non-significant differences between the WBVAT and control groups. CONCLUSIONS: WBVAT treatment may increase BMD in senior people, particularly those with OP and women. Changes in bone metabolism after WBVAT treatment were not observed in most cases.

Zha DS; Zhu QA; Pei WW; Zheng JC; Wu SH; Xu ZX; Li T; Chen JT

2012-02-01

124

Time changes in the reactivity and character of coke deposits formed in thermal cracking of hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

The objective of this contribution is to determine if coke deposits age with time, and if they do so, how such changes affect coke reactivity. Such information would be useful to evaluate cracker operation strategy. A novel reactor system (flow area 3.455 cm/sup 2/ and heated length 58 cm) having removable tabs was employed to study coke deposition from propylene, and propane at 600 to 885/degree/C and atmospheric pressure. The reactivity of coke was determined using TGA. The isothermal gasification was done at 950/degree/C or 600/degree/C either with air or CO/sub 2/. The reactivity was calculated form the burn-off plot. The other tests conducted to characterize coke deposits include: C/H ratio, Scanning Electron Microscopy, X-Ray diffraction and BET Surface Area. For the propylene coke and propane coke no significant change in morphology, crystal parameters, composition and reactivity was seen for aging between 4 and 100 hours. Aging, if any occurs, must be a relatively rapid process or very slow.

Lekshminarayanan, H.; Silveston, P.L.

1988-08-01

125

Radiological changes following second-line zoledronic acid treatment in breast cancer patients with bone metastases.  

UK PubMed Central (United Kingdom)

Initiation of bisphosphonate therapy in bisphosphonate-naïve patients is known to be associated with radiological changes such as increased bone density in both osteolytic and osteoblastic metastases. It is not known, however, whether switching from a second-generation bisphosphonate to a more potent agent is associated with similar changes. This study aimed to prospectively explore radiological changes, as assessed by thoracolumbar CT scanning, in patients switching from an early generation bisphosphonate (i.e., oral clodronate or intravenous pamidronate) to intravenous zoledronic acid. Patients with progressive bone metastases despite use of an earlier generation bisphosphonate were switched to zoledronic acid as part of a study to evaluate the palliative benefit of this intervention. Quantitative computed tomography (QCT) scanning of the thoracolumbar spine was carried out at baseline, and repeated 4 months after commencing zoledronic acid. The effect of this change of therapy was explored in terms of bone density, as well as volume of osteolytic and osteoblastic disease. Fifteen patients were assessed. Switching of bisphosphonate therapy was associated with a significant increase in bone density, and an increase in osteoblastic volume. There was an insignificant trend towards reduced osteolytic volume. In conclusion, switching from early generation bisphosphonates to a more potent agent is associated with radiological changes similar to those seen when commencing a bisphosphonate in treatment-naïve patients. This is consistent with the observed palliative benefit. The use of QCT may be of benefit in the monitoring of bone metastases.

Amir E; Whyne C; Freedman OC; Fralick M; Kumar R; Hardisty M; Clemons M

2009-01-01

126

Radiological changes following second-line zoledronic acid treatment in breast cancer patients with bone metastases.  

Science.gov (United States)

Initiation of bisphosphonate therapy in bisphosphonate-naïve patients is known to be associated with radiological changes such as increased bone density in both osteolytic and osteoblastic metastases. It is not known, however, whether switching from a second-generation bisphosphonate to a more potent agent is associated with similar changes. This study aimed to prospectively explore radiological changes, as assessed by thoracolumbar CT scanning, in patients switching from an early generation bisphosphonate (i.e., oral clodronate or intravenous pamidronate) to intravenous zoledronic acid. Patients with progressive bone metastases despite use of an earlier generation bisphosphonate were switched to zoledronic acid as part of a study to evaluate the palliative benefit of this intervention. Quantitative computed tomography (QCT) scanning of the thoracolumbar spine was carried out at baseline, and repeated 4 months after commencing zoledronic acid. The effect of this change of therapy was explored in terms of bone density, as well as volume of osteolytic and osteoblastic disease. Fifteen patients were assessed. Switching of bisphosphonate therapy was associated with a significant increase in bone density, and an increase in osteoblastic volume. There was an insignificant trend towards reduced osteolytic volume. In conclusion, switching from early generation bisphosphonates to a more potent agent is associated with radiological changes similar to those seen when commencing a bisphosphonate in treatment-naïve patients. This is consistent with the observed palliative benefit. The use of QCT may be of benefit in the monitoring of bone metastases. PMID:19266291

Amir, E; Whyne, C; Freedman, O C; Fralick, M; Kumar, R; Hardisty, M; Clemons, M

2009-03-06

127

Bone changes in patients with chronic uremia; Zmiany kostne w przewleklej mocznicy  

Energy Technology Data Exchange (ETDEWEB)

The X-ray symptomatology of the bone changes in patients with chronic uremia is presented. Such changes have been noted in 7 out of 60 patients (9%). All of them appeared to have overgrowth parathyroid glands which were operated on. (author). 6 refs, 6 figs.

Heciak, J.; Grzesiakowska, U. [Swietokrzyskie Centrum Onkologii, Kielce (Poland)

1994-12-31

128

Bacteria-reactive immune response may induce RANKL-expressing T-cells in the mouse periapical bone loss lesion  

Science.gov (United States)

Introduction The present study investigated if T-cells infiltrating the periapical lesion produce RANKL and whether bacteria infecting the root canal can activate T-cells to produce RANKL. Methods Using a mouse model of periapical lesion induced by artificial dental pulp exposure, the presence of RANKL-positive T-cells and osteoclasts in the periapical lesion was examined by an immuno-histochemical approach. The bacteria colonizing the exposed root canal were identified by 16S ribosomal RNA (rRNA) sequence analysis. The isolated endodontic bacteria were further immunized to normal mice, and sRANKL production by the T-cells isolated from the immunized mice was evaluated by ex vivo culture system. Results RANKL-positive T-cells, along with TARP+ osteoclasts, were identified in periapical bone resorption lesions. The Gram-negative bacterium Pasterurella pnumotropica (P. pnumotropica), which was most frequently detected from root canal of exposed pulp, showed remarkably elevated serum IgG antibody response in pulp-exposed mice compared to control non-treated mice. Immunization of mice with P. pneumotropica induced not only serum IgG antibody but also primed bacteria reactive T-cells that produced sRANKL in response to ex vivo exposure to P. pneumotropica. Conclusion T-cells infiltrating the periapical region express RANKL, and the endodontic bacteria colonizing the root canal appear to induce RANKL expression from bacteria-reactive T-cells, suggesting the possible pathogenic engagement of immune response to endodontic bacteria in the context of developing boneresorptive periapical lesions.

Silva, Marcelo J.B.; Kajiya, Mikihito; AlShwaimi, Emad; Sasaki, Hajime; Hong, Jennifer; Ok, Peter; Rezende, Taia M.B.; Pagonis, Tom C.; White, Robert R.; Paster, Bruce J; Stashenko, Philip; Kawai, Toshihisa

2012-01-01

129

MR imaging evaluation of bone marrow signal change in post-irradiation patients with nasopharyngeal carcinoma.  

UK PubMed Central (United Kingdom)

BACKGROUND: The normal distribution of red and yellow marrow can be altered by therapeutic irradiation, which causes a well-documented sequence of bone marrow changes. This study measured the T1 signal intensity of the clivus and cervical vertebral bodies of NPC patients who had received a complete course of radiation therapy. METHODS: There were 3 categories of patients: Group I: NPC patients who had radiation myelitis; 14 persons which a total 20 times of MRI. Group II: NPC patients, without radiation myelitis; 6 patients, which a total 6 times of MRI. Group III (control group): patients who received MRI of the cervical spine because of cervical spondylosis or HIVD, were total of 45 patients. In the sagittal section of T1WI, the signal intensity of the bone marrow of clivus and C2 to T1 vertebral bodies was measured. RESULTS: 1). There were homogeneous increases of signal intensity of the bone marrow of clivus and C2 to T1 in Groups I and II. 2). There was no statistical difference between Groups I and II. 3). The increased signal intensity of bone marrow after radiation showed no difference in short and long duration between radiation therapy and MR examinations, indicating that bone marrow signal intensities were increased in NPC patients whether or not they had radiation myelitis. CONCLUSIONS: Signal change in bone marrow may have occurred soon after radiation therapy, and may have persisted for several years. The radiation myelitis always involved the low medulla oblongata to C5 level; however, the bone marrow signal change always extended downward to the T1 level, so bone marrow is more sensitive than the spinal cord and is prone to be affected by irradiation.

Shen WC; Chen CC; Chiang CM; Liu CK; Lee SK; Lin JC; Jan JS

1994-04-01

130

The chloride channel inhibitor NS3736 [corrected] prevents bone resorption in ovariectomized rats without changing bone formation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Udgivelsesdato: 2004-Jul , Chloride channel activity is essential for osteoclast function. Consequently, inhibition of the osteoclastic chloride channel should prevent bone resorption. Accordingly, we tested a chloride channel inhibitor on bone turnover and found that it inhibits bone resorption withou...

Schaller, Sophie; Henriksen, Kim; Sveigaard, Christina; Heegaard, Anne-Marie; Hélix, Nathalie; Stahlhut, Martin

131

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

132

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

International Nuclear Information System (INIS)

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).

2000-01-01

133

Changes in macrophage inhibitory factor correlate with changes in bone mineral density in glucocorticoid-treated patients with rheumatoid arthritis.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To investigate whether changes in bone density and turnover are associated with changes in inflammatory mediators in RA patients treated with glucocorticoids (GCs) upon vitamin D treatment in comparison with alendronate treatment. METHODS: RA patients (n?=?40) on long-term oral GC treatment received either alfacalcidol or alendronate. At baseline and after 18 months, we measured cytokines capable of antagonizing GCs [macrophage migration inhibitory factor (MIF), IL-13 and IL-7], cytokines causing T-cell differentiation (IL-6, IL-7, IL-12, IL-10 and IL-23) and cytokines produced by effector T cells (IFN-?, IL-4, IL-17, IL-22). Associations of cytokine profiles with bone markers and BMD changes of the lumbar spine were explored using multiple regression analyses that corrected for study medication and risk factors of osteoporosis (gender, age, cumulative/change in GC dose). RESULTS: Alendronate, unlike alfacalcidol, increased BMD changes in the lumbar spine. Most cytokines were below detection limits. MIF and IL-23 were detectable in almost all samples; neither alfacalcidol nor alendronate significantly influenced serum concentrations of these cytokines. Interestingly, changes in MIF correlated positively with changes in BMD of the lumber spine (Pearson's correlation?=?0.31), and in multivariate analysis adjusting for treatment, age and change in GC dose (P?=?0.022). CONCLUSION: During GC treatment, changes in the GC-antagonist MIF were positively correlated with changes in BMD, which could mean MIF has bone-protecting capacities in patients suffering from GC-induced bone destruction. Further studies need to validate the importance of these findings.

Hoes JN; Van der Goes MC; Jacobs JW; Lafeber FP; Bijlsma JW; Van Roon JA

2011-10-01

134

Changes in Bone Alkaline Phosphatase and Procollagen Type-1 C-Peptide after Static and Dynamic Exercises  

Science.gov (United States)

We investigated the effects of two types of nonweight-bearing exercise on changes in bone-specific alkaline phosphatase (BAP) and pro-collagen type 1 C-peptide (P1P). BAP is a specific marker of bone synthesis, whereas P1P reflects synthesis of type 1 collagen in other organs as well as bone. Eight participants performed static and dynamic…

Kubo, Keitaro; Yuki, Kazuhito; Ikebukuro, Toshihiro

2012-01-01

135

Matrix change of bone grafting substitute after implantation into guinea pig bulla.  

UK PubMed Central (United Kingdom)

BACKGROUND: Many different surgical techniques have been developed to remove open mastoid cavities. In addition to autologous materials, alloplastic substances have been used. A very slow absorption of these materials and extrusion reactions have been reported. We investigated a newly developed, highly porous bone grafting material to eliminate open mastoid cavities, in an animal model. To characterise the transformation process, the early tissue reactions were studied in relation to the matrix transformation of the bone material. MATERIAL AND METHODS: NanoBone (NB), a highly porous bone grafting material based on calcium phosphate and silica, was filled into the open bullae from 20 guinea pigs. The bullae were examined histologically. Energy dispersive X-ray spectroscopy (EDX) was used to investigate the change in the elemental composition at different sampling times. The surface topography of the sections was examined by electron microscopy. RESULTS: After 1 week, periodic acid-Schiffs (PAS) staining demonstrated accumulation of glycogen and proteins, particularly in the border area of the NB particles. After 2 weeks, the particles were evenly coloured after PAS staining. EDX analysis showed a rapid absorption of the silica in the bone grafting material. CONCLUSIONS: NanoBone showed a rapid matrix change after implantation in the bullae of guinea pigs. The absorption of the silica matrix and replacement by PAS-positive substances like glycoproteins and mucopolysaccharides seems to play a decisive role in the degradation processes of NB. This is associated with the good osteoinductive properties of the material.

Punke Ch; Zehlicke T; Just T; Holzhüter G; Gerber T; Pau HW

2012-05-01

136

Nicotine effects on alveolar bone changes induced by occlusal trauma: a histometric study in rats.  

UK PubMed Central (United Kingdom)

BACKGROUND: The aim of the present study was to verify nicotine effects on alveolar bone changes induced by occlusal trauma during a periodontitis experimental model in rats. METHODS: Thirty adult male rats were used. The animals were randomly assigned to one of three groups receiving daily intraperitoneal injections: A, nicotine solution (0.44 mg/ml) and occlusal overload; B, saline solution and occlusal overload; or C, saline solution. Rats from groups A and B underwent bilateral amputation of the second and third molar cusps to simulate an occlusal overload. The first molars were then randomly assigned to receive a cotton ligature in the sulcular area, while the contralateral tooth was left unligated. The animals were sacrificed 30 days later. The resected mandibles were processed, and histomorphometric measurements were performed in the alveolar bone adjacent to the furcation area of the first molars. RESULTS: Nicotine enhanced the bone loss induced by occlusal trauma (P<0.001) on the ligated teeth of group A (12.27 +/- 4.4 mm2), when compared to groups B (8.43 +/- 3.51 mm2) and C (4.43 +/- 2.17 mm2). Alveolar bone loss (P<0.01) was also observed in the contralateral teeth of groups A (nicotine + trauma) and B (saline + trauma), when compared to group C (saline only). CONCLUSION: Within the limits of the study, it is concluded that nicotine may influence the alveolar bone changes induced by occlusal trauma by enhancing bone loss.

Nogueira-Filho GR; Fróes Neto EB; Casati MZ; Reis SR; Tunes RS; Tunes UR; Sallum EA; Nociti FH Jr; Sallum AW

2004-03-01

137

Temporal changes of periprosthetic bone density in patients with a modular noncemented femoral prosthesis.  

Science.gov (United States)

Bone mineral density changes surrounding a porous-coated proximal modular sleeved hip prosthesis were determined as a function of time over a 24-month period. The periprosthetic bone regions were defined by the 7 Gruen zones. Measurements were obtained with a dual-energy x-ray densitometer using a dedicated software program. Inclusion criteria required that the patients had primary implants, were asymptomatic with Harris hip scores of > or =95 for the duration of the study, and showed no radiographic evidence of loosening. The protocol specified that bone measurements be obtained within 1 week after surgery as a baseline reference and at 3, 6, 9, 12, 18, and 24 months thereafter. A total of 111 consecutive patients were enrolled in this ongoing prospective study, of whom 52 had 4 or more measurements after the initial baseline determination for statistical analysis. At 3 months, all zones showed a significant decrease in bone mineral density relative to the baseline measurements, and their mean loss ranged from 6.5% to 11.2%. By 24 months, mineral losses relative to baseline varied from 0 to 11% for Gruen zones 1 to 6. Relative to the 3-month levels, there was no significant change in zones 1, 4, and 6; a significant improvement in zones 3 and 5; and a small but significant loss in zone 2 at 24 months. Gruen zone 7, the medial femoral neck cortex, differed in that it was the site of greatest bone mineral loss, attaining a mean of 20.2% at 24 months. It was found that the amount of periprosthetic mineral loss at 12 months was independent of the initial baseline reference bone mineral levels. Results of this study show the normal temporal bone mineral changes surrounding a proximally modular porouscoated femoral implant. The pattern of change demonstrated may be peculiar to the prosthesis used in this study because it might differ in implants of different design and material composition. PMID:9926956

Rosenthall, L; Bobyn, J D; Brooks, C E

1999-01-01

138

Age-related changes in bone in the dog: calcium homeostasis  

International Nuclear Information System (INIS)

[en] To explore the changes in the relationship between skeletal and Ca2+ homeostasis with age, a study was made of 50 dogs divided into four age groups. The skeletal uptake of 85Sr decreased markedly with age, and the immunoreactive parathyroid hormone (iPTH) level increased. There was a significant correlation between iPTH value and the calculated short-term exchange of Ca in bone. Bone formation and bone resorption decreased with age except that in the oldest group of dogs the resorption increased. The authors suggest that in aging dogs the skeletal exchange of Ca falls to a very low level that decreases the immediate effect of PTH and thus leads to a chronic net increase in circulating PTH. Concomitant with this is an increase in osteoclastic bone resorption and, over a long time, loss of skeletal mass

1984-01-01

139

Tumor-Induced Osteoclast miRNA Changes as Regulators and Biomarkers of Osteolytic Bone Metastasis.  

UK PubMed Central (United Kingdom)

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.

Ell B; Mercatali L; Ibrahim T; Campbell N; Schwarzenbach H; Pantel K; Amadori D; Kang Y

2013-10-01

140

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

 
 
 
 
141

Age-related changes in bone in the dog: calcium homeostasis  

Energy Technology Data Exchange (ETDEWEB)

To explore the changes in the relationship between skeletal and Ca/sup 2 +/ homeostasis with age, a study was made of 50 dogs divided into four age groups. The skeletal uptake of /sup 85/Sr decreased markedly with age, and the immunoreactive parathyroid hormone (iPTH) level increased. There was a significant correlation between iPTH value and the calculated short-term exchange of Ca in bone. Bone formation and bone resorption decreased with age except that in the oldest group of dogs the resorption increased. The authors suggest that in aging dogs the skeletal exchange of Ca falls to a very low level that decreases the immediate effect of PTH and thus leads to a chronic net increase in circulating PTH. Concomitant with this is an increase in osteoclastic bone resorption and, over a long time, loss of skeletal mass.

Williams, E.A.; Kelly, P.J.

1984-01-01

142

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

International Nuclear Information System (INIS)

[en] 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)

1991-01-01

143

Divergent Significance of Bone Mineral Density Changes in Aging Depending on Sites and Sex Revealed through Separate Analyses of Bone Mineral Content and Area  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Bone mineral density (aBMD) is equivalent to bone mineral content (BMC) divided by area. We rechecked the significance of aBMD changes in aging by examining BMC and area separately. Subjects were 1167 community-dwelling Japanese men and women, aged 40–79 years. ABMDs of femoral neck and lumbar spine...

Matsui, Yasumoto; Takemura, Marie; Harada, Atsushi; Ando, Fujiko; Shimokata, Hiroshi

144

[Age-related changes in the level of serum bone markers in healthy children].  

Science.gov (United States)

Age-related changes in the blood level of bone metabolic markers were compared in healthy children living in different geographical regions. The absolute value of carboxy-terminal telopeptide of type 1 collagen type 1 (beta-CrossLaps) and that of total procollagen type 1 amino-terminal propeptide (PINP) were found to depend on living conditions and the nature of changes in the serum markers of bone metabolism was related to the processes of natural growth and development in children. A child's individual growth curve can be used to identify target groups for the prevention of osteopenia. PMID:21313747

Ivashkina, T M; Kotova, T N; Omarova, P Sh; Khlekhlina, Iu V; Berestovskaia, V S; Ponkratova, T S

2010-11-01

145

[Age-related changes in the level of serum bone markers in healthy children].  

UK PubMed Central (United Kingdom)

Age-related changes in the blood level of bone metabolic markers were compared in healthy children living in different geographical regions. The absolute value of carboxy-terminal telopeptide of type 1 collagen type 1 (beta-CrossLaps) and that of total procollagen type 1 amino-terminal propeptide (PINP) were found to depend on living conditions and the nature of changes in the serum markers of bone metabolism was related to the processes of natural growth and development in children. A child's individual growth curve can be used to identify target groups for the prevention of osteopenia.

Ivashkina TM; Kotova TN; Omarova PSh; Khlekhlina IuV; Berestovskaia VS; Ponkratova TS

2010-11-01

146

A Wolff in sheep's clothing: trabecular bone adaptation in response to changes in joint loading orientation.  

Science.gov (United States)

This study tests Wolff's law of trabecular bone adaptation by examining if induced changes in joint loading orientation cause corresponding adjustments in trabecular orientation. Two groups of sheep were exercised at a trot, 15 min/day for 34 days on an inclined (7°) or level (0°) treadmills. Incline trotting caused the sheep to extend their tarsal joints by 3-4.5° during peak loading (Pstructure model index, SMI) in the exercised than sedentary sheep. Overall, these results demonstrate that trabecular bone dynamically adjusts and realigns itself in very precise relation to changes in peak loading direction, indicating that Wolff's law is not only accurate but also highly sensitive. PMID:21893221

Barak, Meir M; Lieberman, Daniel E; Hublin, Jean-Jacques

2011-08-26

147

Morphological Change of Heat Treated Bovine Bone: A Comparative Study  

Directory of Open Access Journals (Sweden)

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.

Sumit Pramanik; Asyikin Sasha Mohd Hanif; Belinda Pingguan-Murphy; Noor Azuan Abu Osman

2012-01-01

148

Bone marrow changes after localized acute and fractionated x irradiation  

Energy Technology Data Exchange (ETDEWEB)

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.

El-Naggar, A.M.; Hanna, I.R.A.; Chanana, A.D.; Carsten, A.L.; Cronkite, E.P.

1980-10-01

149

Bone marrow changes after localized acute and fractionated x irradiation  

International Nuclear Information System (INIS)

[en] 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

1980-01-01

150

Bone mineral change during experimental heating: an X-ray scattering investigation.  

UK PubMed Central (United Kingdom)

The effects of heating and burning on bone mineral have previously been studied using techniques such as X-ray diffraction (XRD) with the aim of discerning a characteristic signature of crystal change. This would enable a better understanding of alteration to bone mineral during heating, which would in turn impact on the preparation and use of natural bone hydroxyapatite as a biomaterial resource. In addition, this knowledge could prove invaluable in the investigation of burned human remains from forensic and archaeological contexts in cremation and funerary practice. Here we describe a complementary method, small-angle X-ray scattering (SAXS), to determine more accurately the changes to bone crystallite size and shape during an experimental heating regimen. Samples were subjected to controlled heating at 500 degrees C, 700 degrees C, or 900 degrees C for 15 or 45 min. Our results show bone crystallites begin to alter in the first 15 min of heating to 500 degrees C or above. They then appear to stabilise to a temperature-specific thickness and shape with prolonged heating. While the samples heated to lower temperatures or for shorter periods produce XRD traces showing little alteration to the apatite, corresponding information obtained from SAXS shows an early, subtle change in crystal parameters.

Hiller JC; Thompson TJ; Evison MP; Chamberlain AT; Wess TJ

2003-12-01

151

Bone mineral change during experimental heating: an X-ray scattering investigation.  

Science.gov (United States)

The effects of heating and burning on bone mineral have previously been studied using techniques such as X-ray diffraction (XRD) with the aim of discerning a characteristic signature of crystal change. This would enable a better understanding of alteration to bone mineral during heating, which would in turn impact on the preparation and use of natural bone hydroxyapatite as a biomaterial resource. In addition, this knowledge could prove invaluable in the investigation of burned human remains from forensic and archaeological contexts in cremation and funerary practice. Here we describe a complementary method, small-angle X-ray scattering (SAXS), to determine more accurately the changes to bone crystallite size and shape during an experimental heating regimen. Samples were subjected to controlled heating at 500 degrees C, 700 degrees C, or 900 degrees C for 15 or 45 min. Our results show bone crystallites begin to alter in the first 15 min of heating to 500 degrees C or above. They then appear to stabilise to a temperature-specific thickness and shape with prolonged heating. While the samples heated to lower temperatures or for shorter periods produce XRD traces showing little alteration to the apatite, corresponding information obtained from SAXS shows an early, subtle change in crystal parameters. PMID:14568425

Hiller, J C; Thompson, T J U; Evison, M P; Chamberlain, A T; Wess, T J

2003-12-01

152

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

International Nuclear Information System (INIS)

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 ?g/day subcutaneous) who had 99mTc-methylene diphosphonate (MDP) bone scans (baseline, 3 and 18 months, then after 6 months off therapy). Women were injected with 600 MBq 99mTc-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 99mTc-MDP skeletal plasma clearance (Kbone). Regional Kbone 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 Kbone 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 Kbone changes were three times larger than other sites. After 6 months off therapy, all Kbone and BTM values returned towards baseline. The increased 99mTc-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 99mTc-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.)

2012-01-01

153

Pathologic changes in the maxillary sinus wall after conservative therapy in odontogenic maxillary sinusitis. Examination using bone scintigraphy  

International Nuclear Information System (INIS)

Single photon emission computed tomographic bone scintigraphy (bone SPECT) was performed in 16 patients with odontogenic maxillary sinusitis to compare inflammatory changes in the maxillary sinus wall including the alveolar process (bony lesions) before and after conservative therapy. Morphologic changes in bony lesions as evaluated by bone SPECT images correlated with those of the maxillary sinus mucosa (mucosal lesions) as evaluated by CT images. Morphologic changes in the bony lesions also correlated with changes in inflammatory activity in the maxillary alveolar process as functionally evaluated by bone SPECT before and after conservative therapy. Odontogenic maxillary sinusitis is considered a disease in which maxillary alveolitis causes mucosal lesions as well as bony lesions. Changes in alveolitis are associated with morphologic changes in bony lesions after conservative therapy, and these changes affect the pathophysiologic nature of odontogenic maxillary sinusitis. Bone SPECT is valuable for predicting outcome and treatment planning in patients with odontogenic maxillary sinusitis. (author)

2003-01-01

154

An elemental analysis of archaeological bone from Sicily as a test of predictability of diagenetic change.  

UK PubMed Central (United Kingdom)

Cortical human bone samples from three tightly dated components of a single Sicilian site were chemically analyzed employing the highly sensitive technique of inductively coupled plasma emission spectroscopy. Although the skeletons appeared to be excellently preserved, significant diagenesis was detected. Moreover, a majority of the elements tested showed no constant or linear variation over time, implying that diagenetic change tends not to be a predictable function of duration of interment. Variation among major long bones of a single skeleton was quite high, as was variation across the cortex. The latter may reflect chemical inhomogeneity in bone tissue or may be an artifact of postmortem change. The results demonstrate the hazards of unsuspected and unpredictable diagenesis, which must be controlled before reliable dietary inferences can be drawn.

Klepinger LL; Kuhn JK; Williams WS

1986-07-01

155

Quantitative ultrasound imaging detects degenerative changes in articular cartilage surface and subchondral bone  

Energy Technology Data Exchange (ETDEWEB)

Previous studies have suggested that quantitative ultrasound imaging could sensitively diagnose degeneration of the articular surface and changes in the subchondral bone during the development of osteoarthrosis (OA). We have recently introduced a new parameter, ultrasound roughness index (URI), for the quantification of cartilage surface roughness, and successfully tested it with normal and experimentally degraded articular surfaces. In this in vitro study, the applicability of URI was tested in bovine cartilage samples with spontaneously developed tissue degeneration. Simultaneously, we studied the sensitivity of quantitative ultrasound imaging to detect degenerative changes in the cartilage-bone interface. For reference, histological degenerative grade of the cartilage samples was determined. Mechanical reference measurements were also conducted. Cartilage surface roughness (URI) was significantly (p < 0.05) higher in histologically degenerated samples with inferior mechanical properties. Ultrasound reflection at the cartilage-bone interface was also significantly (p < 0.05) increased in degenerated samples. Furthermore, it was quantitatively confirmed that ultrasound attenuation in the overlying cartilage significantly affects the measured ultrasound reflection values from the cartilage-bone interface. To conclude, the combined ultrasound measurement of the cartilage surface roughness and ultrasound reflection at the cartilage-bone interface complement each other, and may together enable more sensitive and quantitative diagnosis of early OA or follow up after surgical cartilage repair.

Saarakkala, Simo [Department of Nuclear Medicine, Etelae-Savo Hospital District, Mikkeli Central Hospital, Porrassalmenkatu 35-37, 50100 Mikkeli (Finland); Laasanen, Mikko S [Information Technology R and D Unit, Engineering Kuopio, Savonia Polytechnic, POB 1188, FIN-70211 Kuopio (Finland); Jurvelin, Jukka S [Department of Physics, University of Kuopio, POB 1627, FIN-70211 Kuopio (Finland); Toeyraes, Juha [Department of Clinical Neurophysiology, Kuopio University Hospital and University of Kuopio, POB 1777, FIN-70211 Kuopio (Finland)

2006-10-21

156

Seasonal changes in vitamin D status and bone turnover in healthy Irish postmenopausal women  

DEFF Research Database (Denmark)

Objectives: To examine the effect of season on biochemical markers of bone turnover in 51-to 75-year-old Irish women and to investigate whether such changes are related to vitamin D status. Design: Longitudinal observational study. Setting: Cork, Ireland (52 degrees N). Subjects: 76 apparently healthy, free-living postmenopausal women (aged 51-75 years), not taking any medication and free from any condition likely to affect vitamin D status or calcium/bone metabolism. Results: Serum 25-hydroxyvitamin D [S-25(OH)D] showed a clear seasonal variation with significantly higher (p = or <50 nmol/L (vitamin D adequate and inadequate, respectively) during late-winter, showed that Ur-Pyr and Ur-Dpyr in bothgroups were significantly (p <0.05) lower during late summer, and the magnitude of the reduction from winter to summer was similar in both groups. Conclusion: Seasonal changes in bone resorption markers appeared to be linked to seasonal changes in vitamin D status. Further research is needed to investigate the impact of these changes on risk of bone loss and fracture.

Hill, T.R.; McCarthy, D.

2007-01-01

157

Participation of Bone Marrow-Derived Cells in Fibrotic Changes in Denervated Skeletal Muscle  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In denervated skeletal muscle, mononuclear interstitial cells accumulate in the perisynaptic regions before fibrotic change occurs. These cells are currently considered to be fibroblasts that originate from muscle tissue. However, when we denervated hind limbs of GFP-bone marrow chimeric mice by exc...

Mochizuki, Yasushi; Ojima, Koichi; Uezumi, Akiyoshi; Masuda, Satoru; Yoshimura, Kotaro; Takeda, Shin’ichi

158

Relationship between bone mineral density changes and fracture risk reduction in patients treated with strontium ranelate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Objective: Our objective was to analyze the relationship between bone mineral density (BMD) changes and fracture incidence during 3-yr treatment with strontium ranelate. Patients: Women from the strontium ranelate arm of the Spinal Osteoporosis Therapeutic Intervention study and the TReatment Of Per...

Bruyère, Olivier; Roux, C.; Detilleux, Johann; Slosman, D. O.; Spector, T. D.; Fardellone, P.; Brixen, K.; Devogelaer, J. P.

159

Relationship between bone mineral density changes and fracture risk reduction in patients treated with strontium ranelate  

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  Udgivelsesdato: 2007-Aug , OBJECTIVE: Our objective was to analyze the relationship between bone mineral density (BMD) changes and fracture incidence during 3-yr treatment with strontium ranelate. PATIENTS: Women from the strontium ranelate arm of the Spinal Osteoporosis Therapeutic Intervention stud...

Bruyere, Olivier; Roux, Christian; Detilleux, Johann; Slosman, Daniel O; Spector, Tim D; Fardellone, Patrice; Brixen, Kim

160

Spatial and temporal changes of subchondral bone proceed to microscopic articular cartilage degeneration in guinea pigs with spontaneous osteoarthritis.  

UK PubMed Central (United Kingdom)

OBJECTIVE: This study aimed to investigate the spatial and temporal subchondral bone change of Dunkin-Hartley (DH) strain guinea pigs spontaneous osteoarthritis (OA) model at early stage with three-dimensional Microfocal Computed Tomography (Micro-CT) analysis, histology and immunohistochemistry. MATERIALS AND METHODS: Knee joints of DH and Bristol Strain 2 (BS2) guinea pigs were analyzed at 1, 2 and 3 months of age for early staged subchondral bone ultrastructure change of OA by Micro-CT and histology. And cartilage degeneration was monitored by histological examination. In addition, expression of Osterix was quantified by immunohistochemistry. RESULTS: Microscopic cartilage degeneration was not found at first 3 months in both DH and BS2 guinea pigs. Subchondral bone sclerosis with trabecular ultrastructure turnover was characterized in subchondral bone of DH guinea pigs. Increased thickness, bone mineral density with decreased porosity were defined in subchondral plate of DH guinea pigs. Subchondral trabecular bone was found to be plate-like, convex and isotropy with higher bone volume. Histology confirmed the finding of lower porosity at osteochondral junction and increased bone volume. Immunohistochemistry revealed that the early OA subchondral bone change may be due to elevated level of osteoblast differentiation. CONCLUSIONS: Subchondral bone ultrastructure change occurred at early stage of OA ahead of microscopic cartilage degeneration, which may further impair articular cartilage. It was possibly related to elevated level of osteoblast differentiation.

Wang T; Wen CY; Yan CH; Lu WW; Chiu KY

2013-04-01

 
 
 
 
161

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

UK PubMed Central (United Kingdom)

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.

Tubi? A; Agbaba J; Dalmacija B; Molnar J; Maleti? S; Watson M; Perovi? SU

2013-03-01

162

Calculating kinetics parameters and reactivity changes with continuous-energy Monte Carlo  

Energy Technology Data Exchange (ETDEWEB)

The iterated fission probability interpretation of the adjoint flux forms the basis for a method to perform adjoint weighting of tally scores in continuous-energy Monte Carlo k-eigenvalue calculations. Applying this approach, adjoint-weighted tallies are developed for two applications: calculating point reactor kinetics parameters and estimating changes in reactivity from perturbations. Calculations are performed in the widely-used production code, MCNP, and the results of both applications are compared with discrete ordinates calculations, experimental measurements, and other Monte Carlo calculations.

Kiedrowski, Brian C [Los Alamos National Laboratory; Brown, Forrest B [Los Alamos National Laboratory; Wilson, Paul [UNIV. WISCONSIN

2009-01-01

163

Comparative study of longitudinal changes in peri-implant bone microstructure  

International Nuclear Information System (INIS)

[en] The load applied to an implant is directly transmitted to the jaw and is considered to be one of the causes of remodeling of internal trabecular bones. However, the longitudinal changes during loading and the rearrangement of the trabecular bone structure are mostly unknown. The aim of this study was to clarify the changes in internal jaw bone structure longitudinally during natural tooth eruption as well as tooth extraction and post-implantation periods in a dog model by micro computed tomography (micro-CT). Maxillae of 16 male beagle dogs were used in this study. First, 4 dogs with all maxillary molar teeth erupted were euthanized as a control group. Next, 6 teeth consisting of the bilateral maxillary fourth premolars, and first and second molars were extracted from each of the 12 dogs. Then, 4 dogs of the tooth-extracted group were euthanized 3 months after extraction of the teeth. At this time, three implants were inserted in the left side of the maxilla of the remaining 8 dogs, and the superstructures were placed after 3 months. Four of these 8 dogs with implants were euthanized at 3 months and the other 4 at 1 year after placement of the superstructure. Then, the maxillary bone was removed from each dog as a specimen and sequential micro-CT images were taken. After reconstruction of three-dimensional images, morphological and metrical observation of the jaw trabecular bone structure was performed. A decrease of the trabecular bone in the tooth-extracted group was morphologically and morphometrically observed, whereas the implanted group showed thick, rich trabecular bone. Although a longitudinal decrease in the bone tissue volume was recognized both in the tooth-extracted and the implanted groups, the amount was smaller in the implanted group than in the tooth-extracted group. The results suggested that the application of load by implants in the case of tooth loss inhibits resorption of the alveolar bone and prevents thinning of the jaw. (author)

2010-01-01

164

Beta-amyloid-induced changes in cultured astrocytes parallel reactive astrocytosis associated with senile plaques in Alzheimer's disease.  

UK PubMed Central (United Kingdom)

One neuropathological characteristic of Alzheimer's disease is an abundance of reactive astrocytes, particularly in association with senile plaques. Neither the factor(s) responsible for initiating the reactive astrocytosis nor the effects of this event on disease progression are known. We investigated the possibility that beta-amyloid protein, the primary constituent of plaques, contributes to reactive astrocytosis by comparing results derived from both culture studies and immunohistochemical analyses of Alzheimer brain tissue. We report that beta-amyloid peptides, in an aggregation-dependent manner, rapidly induce a reactive phenotype in cultured rat astrocytes. Reactive morphological changes are accompanied by increased immunoreactivities for glial fibrillary acidic protein and basic fibroblast growth factor. Although toxic to other types of central nervous system cells, aggregated beta-amyloid peptides do not significantly decrease astrocyte viability. Rather, the processes of cultured astrocytes envelop aggregated deposits of beta-amyloid peptide. In Alzheimer brain, the processes of reactive astrocytes were also observed to engulf beta-amyloid deposits. Similar to the in vitro findings, the astrocytic response was associated only with beta-amyloid plaques exhibiting an aggregated structure. Further, the plaque-associated reactive astrocytes showed enhanced immunoreactivities for glial fibrillary acidic protein and basic fibroblast growth factor. These data suggest that beta-amyloid which has assembled into beta-sheet fibrils significantly contributes to the reactive astrocytosis characteristic of Alzheimer's disease. Thus, in addition to its hypothesized direct effects on neuronal viability, beta-amyloid may also influence disease progression indirectly via reactive astrocytosis.

Pike CJ; Cummings BJ; Monzavi R; Cotman CW

1994-11-01

165

Beta-amyloid-induced changes in cultured astrocytes parallel reactive astrocytosis associated with senile plaques in Alzheimer's disease.  

Science.gov (United States)

One neuropathological characteristic of Alzheimer's disease is an abundance of reactive astrocytes, particularly in association with senile plaques. Neither the factor(s) responsible for initiating the reactive astrocytosis nor the effects of this event on disease progression are known. We investigated the possibility that beta-amyloid protein, the primary constituent of plaques, contributes to reactive astrocytosis by comparing results derived from both culture studies and immunohistochemical analyses of Alzheimer brain tissue. We report that beta-amyloid peptides, in an aggregation-dependent manner, rapidly induce a reactive phenotype in cultured rat astrocytes. Reactive morphological changes are accompanied by increased immunoreactivities for glial fibrillary acidic protein and basic fibroblast growth factor. Although toxic to other types of central nervous system cells, aggregated beta-amyloid peptides do not significantly decrease astrocyte viability. Rather, the processes of cultured astrocytes envelop aggregated deposits of beta-amyloid peptide. In Alzheimer brain, the processes of reactive astrocytes were also observed to engulf beta-amyloid deposits. Similar to the in vitro findings, the astrocytic response was associated only with beta-amyloid plaques exhibiting an aggregated structure. Further, the plaque-associated reactive astrocytes showed enhanced immunoreactivities for glial fibrillary acidic protein and basic fibroblast growth factor. These data suggest that beta-amyloid which has assembled into beta-sheet fibrils significantly contributes to the reactive astrocytosis characteristic of Alzheimer's disease. Thus, in addition to its hypothesized direct effects on neuronal viability, beta-amyloid may also influence disease progression indirectly via reactive astrocytosis. PMID:7891862

Pike, C J; Cummings, B J; Monzavi, R; Cotman, C W

1994-11-01

166

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

Directory of Open Access Journals (Sweden)

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; Beadel G

2003-01-01

167

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

Energy Technology Data Exchange (ETDEWEB)

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

168

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

International Nuclear Information System (INIS)

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)

2002-01-01

169

[Changes in bone mass with age. Transversal study on a female population using photon densitometry  

UK PubMed Central (United Kingdom)

In order to evaluate the age-related changes of the bone mineral content (BMC), 281 clinically healthy women (20-80 year old) underwent single photon abosorptiometry (SPA) on the distal third of the radius (where there is a prevalence of cortical bone); 161 subjects of this group were examined also by dual photon absorptiometry (DPA) of the lumbar tract of the spine (L2-L4) (trabecular bone). The relationship of trabecular BMC with age is described by a cubic polynomial regression (r = 0.46; p less than 0.0001) that shows an increase in BMC until 31 years of age followed by a decrease with a minimum at the age of 78; afterwards trabecular BMC adds an apparent increase. No increase in the rate of trabecular BMC loss was seen after the menopause. A positive correlation was found between body weight and vertebral BMC. The behaviour of cortical BMC with age is described by a quadratic regression (r = 0.42; p less than 0.0001) that shows an increase until 32 years of age followed by a decrease. Cortical BMC shows a significant decrease after menopause. No correlation was found between body weight and cortical BMC. These findings underline the different behaviour of trabecular and cortical bone tissue with age; in addition, the relation between trabecular (but not cortical) BMC and body weight argues for an important role of biomechanical factors in the local modulation of bone mass.

Palummeri E; Girasole G; Davoli L; Bergonzani M; Pioli G; Meola P; Butturini L; Barbagallo M; Ciotti G; Pedrazzoni M

1987-06-01

170

The impact of degenerative spinal changes on the correlation of peripheral and axial bone density  

Energy Technology Data Exchange (ETDEWEB)

Results of bone density measurements by quantitative computed tomography of the peripheral skeleton (pQCT) were compared with those of measurements at the axial skeleton with a view to study the effects of degenerative spinal changes on the validity of bone densitometry of the lumbar spine. 556 consecutive patients were examined by dual-energy X-ray absorptiometry (DXA) of the spine and by peripheral quantitative computed tomography (pQCT) of the distal radius. There were significant differences between the bone mineral values at the distal radius and those at the spine, depending on the degree of spinal degeneration. As expected, spinal degenerations showed a highly significant age dependence. With increasing degeneration the correlations between the radius total bone mineral concentration and the bone density of the lumbar spine decreased from r=0.45 to 0.23 in women and from r=0.64 to 0.28 in men. We conclude that the value of spinal DXA is reduced in patients with degenerative spinal disease, compared to the pQCT at the peripheral skeleton. (orig.)

Schneider, P. (Klinik und Poliklinik fuer Nuklearmedizin, Wuerzburg Univ. (Germany)); Boerner, W. (Klinik und Poliklinik fuer Nuklearmedizin, Wuerzburg Univ. (Germany))

1994-08-01

171

Hepatitis B serological changes following allogeneic bone marrow transplantation.  

UK PubMed Central (United Kingdom)

Hepatitis B (HBV) reverse seroconversion (RS) in immunocompromised patients with serological evidence of past HBV infection (hepatitis B surface antigen [sAg] negative, core antibody [cAb] positive) has been reported with increasing frequency following allogeneic hematopoietic stem cell transplant (allo-HSCT). We performed a retrospective review of serial HBV serological testing in patients who had undergone allo-HSCT at our center between 2000 and 2006. We identified 12 patients with serological evidence of past HBV, including 1 case of RS. Although 7 of these 12 patients had no changes in serological markers detected after transplantation, 5 of them had declining levels of hepatitis B surface antibodies [sAb], with 2 to < 10 IU/mL. The remaining 4 patients with past HBV had loss of antiHBcAb. An additional 14 patients developed isolated antiHBcAb post allo-HSCT in the setting of receiving HBV screened (HBsAg, antiHBcAb) negative donor stem cells. Monitoring of HBV serological markers (including antiHBsAb) and HBV DNA levels pre allo-HSCT in recipients and donors, and post allo-SCT in recipients, would allow early detection and treatment of RS and identify new acquisition of HBV.

Teh BW; Slavin MA; Szer J; Sasadeusz JJ

2013-02-01

172

Labeling the human skeleton with 41Ca to assess changes in bone calcium metabolism  

International Nuclear Information System (INIS)

Bone research is limited by the methods available for detecting changes in bone metabolism. While dual X-ray absorptiometry is rather insensitive, biochemical markers are subject to significant intra-individual variation. In the study presented here, we evaluated the isotopic labeling of bone using 41Ca, a long-lived radiotracer, as an alternative approach. After successful labeling of the skeleton, changes in the systematics of urinary 41Ca excretion are expected to directly reflect changes in bone Ca metabolism. A minute amount of 41Ca (100 nCi) was administered orally to 22 postmenopausal women. Kinetics of tracer excretion were assessed by monitoring changes in urinary 41Ca/40Ca isotope ratios up to 700 days post-dosing using accelerator mass spectrometry and resonance ionization mass spectrometry. Isotopic labeling of the skeleton was evaluated by two different approaches: (i) urinary 41Ca data were fitted to an established function consisting of an exponential term and a power law term for each individual; (ii) 41Ca data were analyzed by population pharmacokinetic (NONMEM) analysis to identify a compartmental model that describes urinary 41Ca tracer kinetics. A linear three-compartment model with a central compartment and two sequential peripheral compartments was found to best fit the 41Ca data. Fits based on the use of the combined exponential/power law function describing urinary tracer excretion showed substantially higher deviations between predicted and measured values than fits based on the compartmental modeling approach. By establishing the urinary 41Ca excretion pattern using data points up to day 500 and extrapolating these curves up to day 700, it was found that the calculated 41Ca/40Ca isotope ratios in urine were significantly lower than the observed 41Ca/40Ca isotope ratios for both techniques. Compartmental analysis can overcome this limitation. By identifying relative changes in transfer rates between compartments in response to an intervention, inaccuracies in the underlying model cancel out. Changes in tracer distribution between compartments were modeled based on identified kinetic parameters. While changes in bone formation and resorption can, in principle, be assessed by monitoring urinary 41Ca excretion over the first few weeks post-dosing, assessment of an intervention effect is more reliable ?150 days post-dosing when excreted tracer originates mainly from bone. (orig.)

2006-01-01

173

Labeling the human skeleton with {sup 41}Ca to assess changes in bone calcium metabolism  

Energy Technology Data Exchange (ETDEWEB)

Bone research is limited by the methods available for detecting changes in bone metabolism. While dual X-ray absorptiometry is rather insensitive, biochemical markers are subject to significant intra-individual variation. In the study presented here, we evaluated the isotopic labeling of bone using {sup 41}Ca, a long-lived radiotracer, as an alternative approach. After successful labeling of the skeleton, changes in the systematics of urinary {sup 41}Ca excretion are expected to directly reflect changes in bone Ca metabolism. A minute amount of {sup 41}Ca (100 nCi) was administered orally to 22 postmenopausal women. Kinetics of tracer excretion were assessed by monitoring changes in urinary {sup 41}Ca/{sup 40}Ca isotope ratios up to 700 days post-dosing using accelerator mass spectrometry and resonance ionization mass spectrometry. Isotopic labeling of the skeleton was evaluated by two different approaches: (i) urinary {sup 41}Ca data were fitted to an established function consisting of an exponential term and a power law term for each individual; (ii) {sup 41}Ca data were analyzed by population pharmacokinetic (NONMEM) analysis to identify a compartmental model that describes urinary {sup 41}Ca tracer kinetics. A linear three-compartment model with a central compartment and two sequential peripheral compartments was found to best fit the {sup 41}Ca data. Fits based on the use of the combined exponential/power law function describing urinary tracer excretion showed substantially higher deviations between predicted and measured values than fits based on the compartmental modeling approach. By establishing the urinary {sup 41}Ca excretion pattern using data points up to day 500 and extrapolating these curves up to day 700, it was found that the calculated {sup 41}Ca/{sup 40}Ca isotope ratios in urine were significantly lower than the observed {sup 41}Ca/{sup 40}Ca isotope ratios for both techniques. Compartmental analysis can overcome this limitation. By identifying relative changes in transfer rates between compartments in response to an intervention, inaccuracies in the underlying model cancel out. Changes in tracer distribution between compartments were modeled based on identified kinetic parameters. While changes in bone formation and resorption can, in principle, be assessed by monitoring urinary {sup 41}Ca excretion over the first few weeks post-dosing, assessment of an intervention effect is more reliable {proportional_to}150 days post-dosing when excreted tracer originates mainly from bone. (orig.)

Denk, E.; Hurrell, R.F.; Walczyk, T. [Institute of Food Science and Nutrition, ETH Zurich, Laboratory of Human Nutrition, Zuerich (Switzerland); Hillegonds, D.; Vogel, J. [Lawrence Livermore National Laboratory, Center for Accelerator Mass Spectrometry, Livermore, CA (United States); Synal, A. [Paul Scherrer Institute/ETH Zurich, Laboratory of Particle Physics, Zuerich (Switzerland); Geppert, C.; Wendt, K. [Johannes Gutenberg University, Institute of Physics, Mainz (Germany); Fattinger, K. [University Hospital Bern, Department of General Internal Medicine, Inselspital, Bern (Switzerland); Hennessy, C.; Berglund, M. [Institute for Reference Materials and Measurements (IRMM), European Commission Joint Research Centre, Geel (Belgium)

2006-11-15

174

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

Directory of Open Access Journals (Sweden)

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

2013-01-01

175

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

Science.gov (United States)

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.

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

2013-01-01

176

Prediction of changes in bone mineral density in postmenopausal women treated with once-weekly bisphosphonates.  

UK PubMed Central (United Kingdom)

BACKGROUND: In clinical practice, bone mineral density (BMD) determined by dual-energy x-ray absorptiometry is used to monitor response to osteoporosis therapy. However, 1 to 2 yr are usually required to assess patients' BMD responses. The possibility of earlier indicators of a response or nonresponse to treatment, such as changes in bone turnover markers (BTMs), is of interest to physicians and patients. METHODS: In this post hoc analysis of women treated with once-weekly bisphosphonates, we examined the association of tertile percentage change from baseline in BTMs at 3 or 6 months and association of several baseline clinical characteristics with 24-month percentage change from baseline in BMD and with percentage of patients showing BMD nonresponse (defined as BMD loss at two or more of four sites) at 24 months. Multivariable analysis was performed to determine which factors were independently associated with BMD nonresponse. RESULTS: Patients in the tertile with the greatest decrease in each of the BTMs had the greatest mean increase in BMD and the lowest percentage of BMD nonresponders at 24 months. Several characteristics were independently associated with BMD nonresponse, including smaller 3-month reductions from baseline in serum C-terminal telopeptide of type 1 collagen, bone-specific alkaline phosphatase, and N-terminal propeptide of type 1 procollagen; younger age of menopause; a family history of osteoporosis; and higher baseline trochanteric BMD. Baseline BTMs were not predictive of 24-month BMD response to therapy. The strongest associations were for changes in BTMs with treatment. CONCLUSION: In groups of patients, short-term changes in markers of bone turnover appear to be predictors of longer term BMD response and nonresponse to bisphosphonate therapy.

Burnett-Bowie SM; Saag K; Sebba A; de Papp AE; Chen E; Rosenberg E; Greenspan SL

2009-04-01

177

Air pressure-induced susceptibility changes in vascular reactivity studies using BOLD MRI.  

UK PubMed Central (United Kingdom)

PURPOSE: To investigate whether compressed air during air-cuff inflation in vascular reactivity studies could induce aberrant blood oxygenation level-dependent (BOLD) signal change. MATERIALS AND METHODS: Magnetic resonance imaging (MRI) experiments were performed on a whole-body 3 T scanner. The pattern of T2* signal change measured from a phantom simulating the lower limb was assessed while a thigh cuff was inflated and deflated. MR spectroscopy was performed on a head phantom wrapped using a hand-cuff to determine the relationship between water peak linewidth and applied cuff pressure. Calf muscles from 14 normal subjects were examined to identify aberrant T2* signal changes in the occluded and nonoccluded legs. RESULTS: A sudden T2* signal drop was observed in the phantom on initiation of cuff inflation with subsequent signal change being dependent on cuff pressure. Water peak linewidth increased linearly with cuff pressure (r(2) = 0.94). Aberrant T2* signal changes were observed in both the occluded and nonoccluded legs. CONCLUSION: Compressed air due to cuff inflation directly affects local magnetic field susceptibility. The T2* sequence is sensitive to local field disturbances induced by an inflated cuff. Muscle BOLD results are affected by high-pressure air, with a sudden drop in T2* signal being a characteristic feature of this induced effect. J. Magn. Reson. Imaging 2013;38:976-980. © 2012 Wiley Periodicals, Inc.

Yeung DK; Griffith JF; Li AF; Ma HT; Yuan J

2013-10-01

178

Changing of bone resorption marker by treatment with infliximab for rheumatoid arthritis  

International Nuclear Information System (INIS)

In order to investigate which clinical factors are associated with bone improvement by treatment with infliximab in rheumatoid arthritis (RA), twelve cases using concise laboratory data were analyzed in terms of urinary N-telopeptides of type I collagen (NTx) one year before and one year after treatment with infliximab. Urinary NTx changed from 41.55±13.5 (20.9-62.8) (nM BCE/mM Cr) to 40.77±16.34 (15-75.7) (nM BCE/mM Cr) and there was no significant difference between before and after treatment with infliximab (p=0.814). There was a significant correlation between improvement of urinary NTX and steroid or RAPA one year after treatment with infliximab (p=0.038 respectively). At less than 80 times RAPA, urinary NTx significantly decreased from 40.0±15.0 (nM BCE/mM Cr) to 29.98±8.65 (nM BCE/mM Cr) (p=0.043). Therefore, low RAPA and low dose of steroid was associated with improvement of urinary NTx after using infliximab. X-ray examination revealed that bone atrophy improved in 8 cases out of 12 (67%) and erosion improved in 1 case out of 12 (8.3%). MRI of the hand was assessed and synovium proliferation decreased in 1 case. Histological findings of the subchondral bone at the time of total elbow replacement during treatment with infliximab revealed newly formed fibrous woven bone, including osteoid material which filled the space of trabecular bone tissue. Therefore, the rheumatoid factor (RF) may be one of the points which indicates bone healing after using infliximab for RA. (author)

2008-01-01

179

Early MR changes in vertebral bone marrow for patients following radiotherapy  

Energy Technology Data Exchange (ETDEWEB)

Our study aimed to evaluate the vertebral marrow changes in patients following radiotherapy (RT) by measuring the T2 relaxation times before and during RT. We were mostly interested in evaluating early MR marrow changes during RT. Fifteen patients treated by RT for cervical cancer were submitted to MR examination before and during RT (5-23 days of RT). T2 values were calculated for irradiated and non-irradiated tissues (lumbar and sacral vertebral bone marrow, symphysis pubis marrow, and regional muscle). Fourteen patients presented increased T2 values for irradiated vertebral bone marrow (VBM), and 3 patients showed increased T2 values even for non-irradiated VBM. We found T2 variations for VBM as early as in the fifth day of RT for an absorbed dose as small as 9 Gy. Calculated T2 values in irradiated and also in non-irradiated tissues prove very early tissue alterations. (orig.)

Onu, M.; Lungu-Solomonescu, C.; Harabagiu, I.; Pop, T. [Dept. of Nuclear Medicine, Clinical Hospital, Echography and MRI, Bucharest (Romania); Savu, M. [Dept. of Radiotherapy, Oncologic Inst., Bucharest (Romania)

2001-08-01

180

Quantitative ultrasound imaging detects degenerative changes in articular cartilage surface and subchondral bone  

Science.gov (United States)

Previous studies have suggested that quantitative ultrasound imaging could sensitively diagnose degeneration of the articular surface and changes in the subchondral bone during the development of osteoarthrosis (OA). We have recently introduced a new parameter, ultrasound roughness index (URI), for the quantification of cartilage surface roughness, and successfully tested it with normal and experimentally degraded articular surfaces. In this in vitro study, the applicability of URI was tested in bovine cartilage samples with spontaneously developed tissue degeneration. Simultaneously, we studied the sensitivity of quantitative ultrasound imaging to detect degenerative changes in the cartilage-bone interface. For reference, histological degenerative grade of the cartilage samples was determined. Mechanical reference measurements were also conducted. Cartilage surface roughness (URI) was significantly (p cartilage repair.

Saarakkala, Simo; Laasanen, Mikko S.; Jurvelin, Jukka S.; Töyräs, Juha

2006-10-01

 
 
 
 
181

Quantitative ultrasound imaging detects degenerative changes in articular cartilage surface and subchondral bone  

International Nuclear Information System (INIS)

Previous studies have suggested that quantitative ultrasound imaging could sensitively diagnose degeneration of the articular surface and changes in the subchondral bone during the development of osteoarthrosis (OA). We have recently introduced a new parameter, ultrasound roughness index (URI), for the quantification of cartilage surface roughness, and successfully tested it with normal and experimentally degraded articular surfaces. In this in vitro study, the applicability of URI was tested in bovine cartilage samples with spontaneously developed tissue degeneration. Simultaneously, we studied the sensitivity of quantitative ultrasound imaging to detect degenerative changes in the cartilage-bone interface. For reference, histological degenerative grade of the cartilage samples was determined. Mechanical reference measurements were also conducted. Cartilage surface roughness (URI) was significantly (p

2006-10-21

182

GROSS CHANGES PRODUCED BY TRACTION FORCE IN LONG BONE OF RABBIT TIBIA  

Directory of Open Access Journals (Sweden)

Full Text Available Effects of traction on long bone growth in 30 rabbits were studied by applying traction in long axis of righttibia. Animals were divided into three equal groups, experimental, sham operated and control group.Radiography was used for measurement of initial and final length of tibia. Traction was applied inexperimental group of animals only. The experimental tibia did not show significant change in its length ascompared to opposite tibia.

Riaz Ahmad

1997-01-01

183

Age-related changes of skin blood flow during postocclusive reactive hyperemia in human.  

UK PubMed Central (United Kingdom)

BACKGROUND/PURPOSE: The objective was to study age-related alterations in the time-amplitude characteristics of the oscillatory components of peripheral blood flow in healthy humans during postocclusive reactive hyperemia. METHODS: Forearm blood skin perfusion was studied by the method of laser Doppler flowmetry in 120 healthy volunteers, who were divided into two age groups: young (19-30 years old; n = 82) and middle-age (30-60 years old; n = 38). The forearm occlusion approach was used to reveal the reaction of the microvascular bed to transient ischemia. To estimate the age-related changes of separate oscillatory components of LDF signals during postocclusive reactive hyperemia, we applied adaptive time-amplitude wavelet analysis. RESULTS: A statistically significant increase in the skin blood perfusion after occlusion removal was revealed: 4-fold in the 1st and 3.5-fold in the 2nd group respectively. Both the amplitude of blood flow oscillations at rest and the postocclusive growth of the amplitude showed an age-related decline in the frequency intervals associated with the myogenic (0.052-0.145 Hz), sympathetic (0.021-0.052 Hz) and endothelial (0.0095-0.021 Hz) activity. CONCLUSION: The time-amplitude characteristics of the oscillatory components of peripheral blood flow depend on age, with the dependence becoming more evident after a transient ischemia.

Tikhonova IV; Tankanag AV; Chemeris NK

2013-02-01

184

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

Energy Technology Data Exchange (ETDEWEB)

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.

Freels, J.D.

1993-07-01

185

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

Energy Technology Data Exchange (ETDEWEB)

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.

Freels, J.D.

1993-01-01

186

Changes in cerebrovascular reactivity following low-frequency repetitive transcranial magnetic stimulation.  

UK PubMed Central (United Kingdom)

OBJECTIVES: Repetitive Transcranial Magnetic Stimulation (rTMS) potential therapeutic uses have been explored in many conditions including stroke. However, its potential effects on cerebral hemodynamics have not been deeply considered. Transcranial Doppler ultrasonography (TCD) is a promising tool in detecting focal changes of cerebral blood flow velocity (CBFV) and cerebrovascular reactivity (CRV) induced by rTMS. We evaluated possible changes in CBFV and CVR in healthy volunteers. METHODS: Low-frequency (1 Hz) and Sham rTMS were applied over the motor cortex (M1) of the left hemisphere of healthy volunteers. CBFV and CVR were evaluated in the ipsilateral middle cerebral artery (MCA). CVR to hypercapnia was derived from the breath-holding index (BHI). Subjects were randomly assigned to real or sham stimulation. RESULTS: Maximal CBFV of MCA tended to decrease after 1 Hz M1 rTMS. Low-frequency 1Hz M1 rTMS increased BHI (measured in MCA) immediately after rTMS, and the observed effect vanished after 15 min when applied over M1. We did not observe any significant change in Pulsatility Index (PI) and Resistance Index (RI) measures in all conditions. No significant changes of above mentioned parameters were observed in the sham stimulation group. CONCLUSIONS: Low-frequency rTMS induces a significant modulation of CVR in healthy subjects. This effect should be relevant in acute stroke patients with impaired cerebral autoregulation.

Sallustio F; Di Legge S; Rizzato B; Stanzione P; Koch G

2010-08-01

187

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

Directory of Open Access Journals (Sweden)

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; Zh Maghbooli; AA Keshtkar; A Soltani; P Ebrahimpour; S Mortaz hejri

2004-01-01

188

The chloride channel inhibitor NS3736 [corrected] prevents bone resorption in ovariectomized rats without changing bone formation.  

UK PubMed Central (United Kingdom)

UNLABELLED: Chloride channel activity is essential for osteoclast function. Consequently, inhibition of the osteoclastic chloride channel should prevent bone resorption. Accordingly, we tested a chloride channel inhibitor on bone turnover and found that it inhibits bone resorption without affecting bone formation. This study indicates that chloride channel inhibitors are highly promising for treatment of osteoporosis. INTRODUCTION: The chloride channel inhibitor, NS3736, blocked osteoclastic acidification and resorption in vitro with an IC50 value of 30 microM. When tested in the rat ovariectomy model for osteoporosis, daily treatment with 30 mg/kg orally protected bone strength and BMD by approximately 50% 6 weeks after surgery. Most interestingly, bone formation assessed by osteocalcin, mineral apposition rate, and mineralized surface index was not inhibited. MATERIALS AND METHODS: Analysis of chloride channels in human osteoclasts revealed that ClC-7 and CLIC1 were highly expressed. Furthermore, by electrophysiology, we detected a volume-activated anion channel on human osteoclasts. Screening 50 different human tissues showed a broad expression for CLIC1 and a restricted immunoreactivity for ClC-7, appearing mainly in osteoclasts, ovaries, appendix, and Purkinje cells. This highly selective distribution predicts that inhibition of ClC-7 should specifically target osteoclasts in vivo. We suggest that NS3736 is inhibiting ClC-7, leading to a bone-specific effect in vivo. RESULTS AND CONCLUSION: In conclusion, we show for the first time that chloride channel inhibitors can be used for prevention of ovariectomy-induced bone loss without impeding bone formation. We speculate that the coupling of bone resorption to bone formation is linked to the acidification of the resorption lacunae, thereby enabling compounds that directly interfere with this process to be able to positive uncouple this process resulting in a net bone gain.

Schaller S; Henriksen K; Sveigaard C; Heegaard AM; Hélix N; Stahlhut M; Ovejero MC; Johansen JV; Solberg H; Andersen TL; Hougaard D; Berryman M; Shiødt CB; Sørensen BH; Lichtenberg J; Christophersen P; Foged NT; Delaissé JM; Engsig MT; Karsdal MA

2004-07-01

189

Changes in bone mineral content after surgical treatment of morbid obesity.  

Science.gov (United States)

Weight loss reduces bone mass and increases the risk of osteoporosis. This study was undertaken to assess changes of bone metabolism following Roux-en-Y gastric bypass (RYGB) and adjustable silicone gastric banding (ASGB) as compared to nonoperated controls of morbidly obese subjects. Fourteen female and 5 male patients with a mean (+/-SEM) age of 44.3 +/- 1.8 years participated in the 24-month prospective study. Nine patients underwent ASGB, 4 patients RYGB operation, and 6 patients were included in the control group. Bone metabolism was assessed by determination of serum parathyroid hormone (PTH), osteocalcin, urinary deoxypyridinoline, and dual energy x-ray absorptiometry (DXA) before, and 6, 12, and 24 months after intervention. The body mass index (BMI) decreased from 41.0 +/- 1.1 to 34.0 +/- 1.4 kg/m2 in the ASGB group (P = .001), from 42.7 +/- 2.2 to 30.5 +/- 2.2 kg/m2 in the RYGB group (P = .006), and remained unchanged in the control group (from 41.2 +/- 1.2 to 41.4 +/- 1.4 kg/m2) after 24 months. Bone mineral content (BMC) showed no significant change in the ASGB group (from 3,079 +/- 140 to 3,064 +/- 129 g) and in the control group (from 2,945 +/- 130 to 2,940 +/- 111 g), whereas it decreased from 2,968 +/- 111 to 2,621 +/- 139 g in the RYGB group (P = .005). The loss in BMC was accompanied by significant increases in urinary deoxypyridinoline (P < .05) and in serum osteocalcin (P < .01) after RYGB, suggesting both, increased bone resorption and increased bone formation. The authors were aware of the fact that the study groups were small and conclusions need to be regarded as preliminary. However, the RYGB operation resulted in enhanced weight loss and significant net loss of bone mass in comparison to ASGB and obese control subjects. Patients losing large amounts of body weight should be monitored regularly regarding prevention of osteoporosis. PMID:15254887

von Mach, M-A; Stoeckli, R; Bilz, S; Kraenzlin, M; Langer, I; Keller, U

2004-07-01

190

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

Energy Technology Data Exchange (ETDEWEB)

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, Cr{sub 2}N 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.

Novakovic, M. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro)]. E-mail: mnovakov@vin.bg.ac.yu; Popovic, M. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro); Perusko, D. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro); Milinovic, V. [II. Physikalisches Institut, Universitaet Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen (Germany); Radovic, I. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro); Bibic, N. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro); Mitric, M. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro); Milosavljevic, M. [VINCA Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia and Montenegro)

2007-04-15

191

Methods for modeling impact-induced reactivity changes in small reactors  

International Nuclear Information System (INIS)

[en] 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.

2010-01-01

192

Hematologic and Bone Marrow Changes in Children with Protein-Energy Malnutrition.  

UK PubMed Central (United Kingdom)

Background: All systems in an organism are affected by protein-energy malnutrition (PEM), but one of the worst affected is the hematopoietic system. Today PEM remains a very serious problem in developing countries. We examined the relationships between clinical features, hematological, and bone marrow changes with severe PEM from Turkey. Method: We evaluated 34 (11 females and 23 males) consecutive cases of severe PEM, with no underlying diseases aged 3-20 months. The clinical nutritional conditions of the patients were determined using the Wellcome-Trust PEM classification. Ten of the patients were in the Marasmic-Kwashiorkor (M-K) group, 10 were in the Kwashiorkor (KW) group, and 14 were in the Marasmic (M) group. Full blood count, protein, albumin, serum iron (SI), iron-binding capacity (TIBC), ferritin, vitamin B12, folic acid, complement-3 (C3), complement-4 (C4), and bone marrow were investigated in all groups. Results: Anemia was detected in 97% of patients. We determined serum iron levels were low in 67.6% of the patients, TS levels were low in 76.4% of the patients and ferritin levels were low in 20.5%. The level of vitamin B12 was normal in all patients. Bone marrow analysis showed erythroid series hypoplasia in 28.5% of patients in the M group, 50% in the KW group, and 30% in the M-K group. Marrow iron was absent in 58.8% of patients. Conclusion: The most common hematologic change in the children with PEM was anemia and major cause of anemia was iron deficiency in this study. Patients with severe PEM have normal Vit B12 and serum folate levels. Most of the patients with severe PEM had normal cellularity with megaloblastic and dysplastic changes in bone marrow due to the inadequate and imbalanced intake of protein and energy.

Ozkale M; Sipahi T

2013-08-01

193

Denosumab and changes in bone turnover markers during androgen deprivation therapy for prostate cancer.  

UK PubMed Central (United Kingdom)

Androgen deprivation therapy (ADT) for prostate cancer increases fracture risk, decreases bone mineral density, and increases bone turnover markers (BTMs) including serum type 1 C-telopeptide (sCTX), tartrate-resistant alkaline phosphatase 5b (TRAP-5b), and procollagen-1 N-terminal telopeptide (P1NP). In a prespecified exploratory analysis of a phase 3, multicenter, double-blind study, we evaluated the effects of denosumab (60 mg subcutaneously every 6 months for 3 years) versus placebo (1468 patients, 734 in each group) on BTM values. BTMs were measured at baseline, month 1, and predose at months 6, 12, 24, and 36 in the overall population. BTMs at month 1 are also reported for subgroups based on age ( 6 months), and baseline BTM (?? median versus >? median BTM values). Treatment with denosumab provided a rapid and sustained decrease of BTM values compared with placebo. The median change in sCTX levels at month 1 was -90% in the denosumab group and -3% in the placebo group (p? change in TRAP-5b levels at month 1 was -55% in the denosumab group and -3% in the placebo group (p?change in P1NP was -64% in the denosumab group and -11% in the placebo group, (p ?bone turnover markers was consistent with marked increases in bone mineral density reported previously.

Smith MR; Saad F; Egerdie B; Sieber P; Tammela TLj; Leder BZ; Ke C; Goessl C

2011-12-01

194

Denosumab and changes in bone turnover markers during androgen deprivation therapy for prostate cancer.  

Science.gov (United States)

Androgen deprivation therapy (ADT) for prostate cancer increases fracture risk, decreases bone mineral density, and increases bone turnover markers (BTMs) including serum type 1 C-telopeptide (sCTX), tartrate-resistant alkaline phosphatase 5b (TRAP-5b), and procollagen-1 N-terminal telopeptide (P1NP). In a prespecified exploratory analysis of a phase 3, multicenter, double-blind study, we evaluated the effects of denosumab (60 mg subcutaneously every 6 months for 3 years) versus placebo (1468 patients, 734 in each group) on BTM values. BTMs were measured at baseline, month 1, and predose at months 6, 12, 24, and 36 in the overall population. BTMs at month 1 are also reported for subgroups based on age ( 6 months), and baseline BTM (?? median versus >? median BTM values). Treatment with denosumab provided a rapid and sustained decrease of BTM values compared with placebo. The median change in sCTX levels at month 1 was -90% in the denosumab group and -3% in the placebo group (p? change in TRAP-5b levels at month 1 was -55% in the denosumab group and -3% in the placebo group (p?change in P1NP was -64% in the denosumab group and -11% in the placebo group, (p ?bone turnover markers was consistent with marked increases in bone mineral density reported previously. PMID:21898590

Smith, Matthew R; Saad, Fred; Egerdie, Blair; Sieber, Paul; Tammela, Teuvo Lj; Leder, Benjamin Z; Ke, Chunlei; Goessl, Carsten

2011-12-01

195

Correlating chemical changes in subchondral bone mineral due to aging or defective type II collagen by Raman spectroscopy  

Science.gov (United States)

We show that early indicators of osteoarthritis are observed in Raman spectroscopy by probing femur surfaces excised from mouse models of early-onset osteoarthritis. Current clinical methods to examine arthritic joints include radiological examination of the joint, but may not be capable of detecting subtle chemical changes in the bone tissue, which may provide the earliest indications of osteoarthritis. Recent research has indicated that the subchondral bone may have a more significant role in the onset of osteoarthritis than previously realized. We will report the effect of age and defective type II collagen on Raman band area ratios used to describe bone structure and function. The carbonate-to-phosphate ratio is used to assess carbonate substitution into the bone mineral and the mineral-to-matrix ratio is used to measure bone mineralization. Mineral-to-matrix ratios indicate that subchondral bone becomes less mineralized as both the wild-type and Del1 (+/-) transgenic mice age. Moreover, the mineral-to-matrix ratios show that the subchondral bone of Del1 (+/-) transgenic mice is less mineralized than that of the wild-type mice. Carbonate-to-phosphate ratios from Del1 (+/-) transgenic mice follow the same longitudinal trend as wild-type mice. The ratio is slightly higher in the transgenic mice, indicating more carbonate content in the bone mineral. Raman characterization of bone mineralization provides an invaluable insight into the process of cartilage degeneration and the relationship with subchondral bone at the ultrastructural level.

Dehring, Karen A.; Roessler, Blake J.; Morris, Michael D.

2007-03-01

196

[Morphological changes of the mandibula with loss of the teeth--observation of the trabecular bone using micro-CT  

UK PubMed Central (United Kingdom)

The jaw bones receive complicated forces not only through the muscles, but through the teeth directly. Therefore, it is thought that the morphology of the jaw bones are greatly effected by the oral conditions. In this paper, the morphological changes of the mandibula with loss of the teeth are descrived. Furthermore, the three dimensional changes of the trabecular bones observed by micro-CT are shown. The jaw bones are of complex composition since they contain the alveolar sockets that encase the dental roots. The structures of the trabecular bone of the mandibula are constructed in order to support the teeth. The trabecular bones appear to have plate-like shape rather than rod-like shape in the three dimensional observation using micro-CT. With loss of the teeth, the height of the mandibula is rapidly shortened. And in the internal structures, both width and volume of the trabecular bone within the substantia spongiosa are reduced and the trabecular bones run in the irregular course. In addition, the plate-like shaped trabecular bones tend to transform into rod-like shaped ones. Based on these findings, it is suggested that maintenance of the intact teeth is important to keep the normal morphology of the mandibula.

Ide Y

2000-08-01

197

Changes in skin test reactivity among adults with atopic disease: a 3-year prospective study  

DEFF Research Database (Denmark)

Background: Our knowledge about longtudinal predictors of atopy is limited. Objectives: To describe changes in skin test reactivity during a 3-year period in a sample of adolescents and adults with atopic disease and to identify factors of importance for these changes. Methods: From a sample of 1, 186 candidates, ranging in age from 14 to 44 years, who in a screening questionnaire reported symptoms suggestive of respiratory allergic disease, 344 individuals with a positive skin prick test (SPT) result concomitantly with asthma and/or rhinitis were clinically studied on 2 occasions, 3 years apart. Results: In total, 134 (39% of the Study population) had a different SPT result at follow-up compared with baseline, based on a diagnostic criterion of 3 min for a positive test result 77 (22%) developed de novo sensitizations to I or more allergens, 45 (13%) had remission of 1 or more sensitizations, and 12 (4%) both gained and lost sensitizations. Female sex (odds ratio = 1.90 [1.02-3.57] P =.04) significantly predicted incidence of 1 or more sensitizations. Conclusions: Four of 10 adults with atopic disease will have changes in SPT status during a 3-year period, and most will gain new sensitizations. Women with atopic disease are at increased risk of developing new sensitizations compared with men Udgivelsesdato: 2008/11

Aslund, N.; Thomsen, S.F.

2008-01-01

198

Cortical bone thickness can adapt locally to muscular loading while changing with age.  

UK PubMed Central (United Kingdom)

Mechanical loading of muscle action is concentrated at muscle attachment sites; thus there may be a potential for site-specific variation in cortical bone thickness. Humeri from an early 20th-century Finnish (Helsinki) and two medieval English (Newcastle, Blackgate and York, Barbican) populations were subjected to pQCT scanning to calculate site-specific cross-sectional cortical bone area (CA) for four locations and to measure cortical thickness at muscle attachment sites and non-attachment sites. We found that CA at 80% of humerus length was significantly reduced compared to more distal cross-sections, which can be due to reduced stresses at the proximal shaft. The principal direction of loading at 80% humerus length was towards mediolateral plane, likely due to fixing the humerus close to the torso. At 35% the main direction of loading was towards anteroposterior plane, reflecting elbow flexing forces. The principal direction of loading varied between populations, sides and sexes at 50% humerus length due to preference between elbow and shoulder joint; thus this location might be useful when trying to infer differences in activity. These changes are likely due to overall shaft adaptation to forces acting at the humerus. In addition, we found a potential for site-specific variation in cortical thickness; cortical bone at muscle attachment sites was significantly thicker compared to non-attachment sites. Lastly, CA at 35% of humerus length and cortical thickness at non-attachment sites decreased with age. These results underline the importance of muscle loading for bone mass preservation as well as indicate that a site-specific variation of bone mass is possible.

Niinimäki S; Söderling S; Junno JA; Finnilä M; Niskanen M

2013-09-01

199

Reactive changes in the Langerhans' cells of human skin caused by occlusion with water and sodium lauryl sulphate.  

UK PubMed Central (United Kingdom)

Human skin was patch tested with sodium lauryl sulphate or with water only for 48 h and biopsied immediately and after 24 h, then analyzed by immunocytochemistry and electron microscopy. Sodium lauryl sulphate produced a decrease in the number of epidermal Langerhans' cells and an increase in dermal Langerhans' cells, with individual variations. The 48-h water occlusion controls showed only slight reactions. Unexpectedly, quite pronounced reactive changes were seen 24 h after termination of water occlusion. Thus, dermal Langerhans' cells were commonly increased and epidermal Langerhans' cells tended to decrease in number. The results indicate that the 24-h interval is not a period of recovery but a period in which more pronounced reactive changes occur. Hydration over 48 h followed by dehydration leading to temporary damage to the epidermal barrier may explain the present findings. Some of the reactive changes observed after sodium lauryl sulphate exposure probably represent the additive effects of occlusion and sodium lauryl sulphate treatment.

Mikulowska A

1990-01-01

200

How does childhood otitis media change the radiological findings of the temporal bone?  

UK PubMed Central (United Kingdom)

CONCLUSION: Inflammatory changes in the middle ear mucosa since childhood may affect mastoid pneumatization without a change in the position of the sigmoid sinus. Also, despite the fact that recurrences of inflammatory middle ear disease lead to bone destruction, we did not see any relationship between the childhood otitis media and bone destruction. OBJECTIVE: To assess radiological findings in temporal bone in both healthy ears and diseased ears in patients with unilateral chronic otitis media since their childhood. METHODS: Twenty-five patients who had unilateral otological symptoms, such as recurrent otalgia, purulent otorrhea or hearing loss since their childhood were included in the study. Assessment of radiological parameters was performed using a quantitative digital image processing computed tomography program. RESULTS: Mastoid volume values in the chronic otitis media group were significantly smaller when compared with those of a healthy group (p < 0.05). In healthy and diseased mastoid groups, there were no significant differences between groups when we assessed Henle spine-sigmoid sinus (HS-SS) distances. There was a significant correlation (p = 0.001) in both the groups when we compared mastoid volume values with HS-SS distances. There was ossicular discontinuity in two cases and in one patient tegmen tympani was not intact in diseased ears.

Habesoglu TE; Habesoglu M; Toros SZ; Deveci I; Surmeli M; Sheidaei S; Baran A; Egeli E

2010-11-01

 
 
 
 
201

[Size and localization of exposed bone surfaces in advanced degenerative changes of the femur head  

UK PubMed Central (United Kingdom)

Area and localization of bone exposure are examined in 37 femoral heads being removed for total arthroplasties. Both are inhomogeneous and show no relation to the duration of clinical complaints nor the changing of stress following limitation of motion or contracture. There have been numerous descriptions of the stress on femoral heads and the location of degenerative cartilage disease in zones of more or less stress, however all theories can be verified or disproved by the types of localization of bone exposure described. The theory that loss of cartilage is not as much due to stress but to chemical alterations cannot be confirmed. A new theory including all observations or a schema of localization of progressive degenerative disease cannot be presented for the present.

Gierse H; Hackenbroch MH

1984-05-01

202

[Size and localization of exposed bone surfaces in advanced degenerative changes of the femur head].  

Science.gov (United States)

Area and localization of bone exposure are examined in 37 femoral heads being removed for total arthroplasties. Both are inhomogeneous and show no relation to the duration of clinical complaints nor the changing of stress following limitation of motion or contracture. There have been numerous descriptions of the stress on femoral heads and the location of degenerative cartilage disease in zones of more or less stress, however all theories can be verified or disproved by the types of localization of bone exposure described. The theory that loss of cartilage is not as much due to stress but to chemical alterations cannot be confirmed. A new theory including all observations or a schema of localization of progressive degenerative disease cannot be presented for the present. PMID:6475223

Gierse, H; Hackenbroch, M H

203

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

204

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)

[en] 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.)

2006-01-01

205

A Wolff in sheep's clothing: trabecular bone adaptation in response to changes in joint loading orientation.  

UK PubMed Central (United Kingdom)

This study tests Wolff's law of trabecular bone adaptation by examining if induced changes in joint loading orientation cause corresponding adjustments in trabecular orientation. Two groups of sheep were exercised at a trot, 15 min/day for 34 days on an inclined (7°) or level (0°) treadmills. Incline trotting caused the sheep to extend their tarsal joints by 3-4.5° during peak loading (P<0.01) but has no effect on carpal joint angle (P=0.984). Additionally, tarsal joint angle in the incline group sheep were maintained more extended throughout the day using elevated platform shoes on their forelimbs. A third "sedentary group" group did not run but wore platform shoes throughout the day. As predicted by Wolff's law, trabecular orientation in the distal tibia (tarsal joint) were more obtuse by 2.7 to 4.3° in the incline group compared to the level group; trabecular orientation was not significantly different in the sedentary and level groups. In addition, trabecular orientations in the distal radius (carpal joint) of the sedentary, level and incline groups did not differ between groups, and were aligned almost parallel to the radius long axis, corresponding to the almost straight carpal joint angle at peak loading. Measurements of other trabecular bone parameters revealed additional responses to loading, including significantly higher bone volume fraction (BV/TV), Trabecular number (Tb.N) and trabecular thickness (Tb.Th), lower trabecular spacing (Tb.Sp), and less rod-shaped trabeculae (higher structure model index, SMI) in the exercised than sedentary sheep. Overall, these results demonstrate that trabecular bone dynamically adjusts and realigns itself in very precise relation to changes in peak loading direction, indicating that Wolff's law is not only accurate but also highly sensitive.

Barak MM; Lieberman DE; Hublin JJ

2011-12-01

206

Bone level changes in dental implants with platform-switched design after immediate and delayed placement in the maxilla.  

UK PubMed Central (United Kingdom)

This study sought to evaluate platform-switched implants for immediate placement. A total of 136 implants were placed in 58 patients using either an immediate or delayed implant protocol. Bone level changes of the implants were measured mesially and distally and statistically analyzed with linear mixed models. No implant was lost. There was no significant difference between immediate and delayed implants in approximal bone level changes during the first year (95% confidence interval: -0.10 to -0.01 for immediate versus -0.14 to -0.07 for delayed implants). Subsequent bone resorption was negligible in both groups.

Heinemann F; Biffar R; Schwahn C; Mundt T

2013-05-01

207

Bone level changes in dental implants with platform-switched design after immediate and delayed placement in the maxilla.  

Science.gov (United States)

This study sought to evaluate platform-switched implants for immediate placement. A total of 136 implants were placed in 58 patients using either an immediate or delayed implant protocol. Bone level changes of the implants were measured mesially and distally and statistically analyzed with linear mixed models. No implant was lost. There was no significant difference between immediate and delayed implants in approximal bone level changes during the first year (95% confidence interval: -0.10 to -0.01 for immediate versus -0.14 to -0.07 for delayed implants). Subsequent bone resorption was negligible in both groups. PMID:23593630

Heinemann, Friedhelm; Biffar, Reiner; Schwahn, Christian; Mundt, Torsten

208

Factors Predicting Bone Mineral Density (BMD) Changes in Young Women over A One-year Study:Changes in Body Weight and Bone Metabolic Markers during the Menstrual Cycle and Their Effects on BMD  

Directory of Open Access Journals (Sweden)

Full Text Available Currently, 26% of Japanese women in their twenties are under weight, and therefore at risk of developing various metabolic abnormalities due to an inadequate nutrient intake, which in turn affects the acquisition of a peak bone mineral density (BMD). In this study, we aimed to clarify the effects of menstrual cycle-related changes in body weight and bone metabolic marker levels on the BMD changes. The subjects were 42 women (19.6±0.8 years). The levels of osteocalcin (OC), BAP, s-NTx, u-DPD, and E2 in the menstrual and ovulatory phases were measured. The associations between dependent variables (BMD changes/year in the lumbar spine, femur, femoral neck) and explanatory variables (body weight changes/year, the levels of OC, BAP, s-NTx, u-DPD) were evaluated using multiple regression analysis. Analysis of the correlations between the changes in bone metabolic markers and changes in BMD showed a correlation between the OC level in the menstrual phase and changes in the BMD of the entire femur, suggesting that a high OC level protects against BMD reduction, probably by promoting osteoblast activity, and that bone formation activity suppresses the decrease in BMD. These results suggest that, to predict BMD changes from bone metabolic markers in young women, it is necessary to measure OC levels in the menstrual phase.

Iida,Tadayuki; Chikamura,Chiho; Ishikawa,Hiroaki; Aoi,Satomi; Ikeda,Hiromi; Harada,Toshihide; Katada,Kazuhiro; Ishizaki,Fumiko; Yatsuya,Hiroshi; Ono,Yuichiro

2012-01-01

209

Toxin-induced conditioned changes in taste reactivity and the role of the chemosensitive area postrema.  

UK PubMed Central (United Kingdom)

Conditioned taste avoidances (CTAs) are an important component of behavioral regulation of ingestion. In the laboratory CTAs can be produced by pairing a novel taste stimulus with the physiological feedback produced by a toxin, such as lithium. Such toxins putatively activate a chemosensitive brainstem structure, the area postrema, which ultimately results in the production of a CTA. The present review describes a series of studies which examined conditioned changes in taste reactivity responses (TRRs) when a novel intraoral sucrose taste was paired with the effects of an intraperitoneal (IP) injection of LiCl, and the role of the area postrema in the formation of conditioned palatability shifts. It was first of all necessary to examine the effects of area postrema ablations on TRRs to a range of intraoral sucrose and quinine stimulus intensities. In the first study area postrema lesioned rats exhibited concentration dependent changes in TRRs to these taste stimuli that were very similar to those exhibited by sham lesioned rats. The second study demonstrated that 30 s intraoral infusions of sucrose (0.3 M), presented at 5 or 10 min intervals following an IP injection of LiCl (3.0 meq), resulted in conditioned changes in TRRs. These were characterized by orderly, gradual reductions in ingestive responses and increases in aversive responses. Finally, when area postrema lesioned rats (Study 3) were subjected to this conditioning procedure (brief sucrose presentations paired with the effects of LiCl) no evidence for conditioned or unconditioned changes in TRRs to sucrose were obtained. Lesioned rats injected with LiCl behaved similarly to sham lesioned rats injected with NaCl. These series of studies provide evidence indicating that the chemosensitive area postrema mediates the formation of conditioned palatability shifts induced by treatment with a toxin such as lithium.

Ossenkopp KP; Eckel LA

1995-01-01

210

Toxin-induced conditioned changes in taste reactivity and the role of the chemosensitive area postrema.  

Science.gov (United States)

Conditioned taste avoidances (CTAs) are an important component of behavioral regulation of ingestion. In the laboratory CTAs can be produced by pairing a novel taste stimulus with the physiological feedback produced by a toxin, such as lithium. Such toxins putatively activate a chemosensitive brainstem structure, the area postrema, which ultimately results in the production of a CTA. The present review describes a series of studies which examined conditioned changes in taste reactivity responses (TRRs) when a novel intraoral sucrose taste was paired with the effects of an intraperitoneal (IP) injection of LiCl, and the role of the area postrema in the formation of conditioned palatability shifts. It was first of all necessary to examine the effects of area postrema ablations on TRRs to a range of intraoral sucrose and quinine stimulus intensities. In the first study area postrema lesioned rats exhibited concentration dependent changes in TRRs to these taste stimuli that were very similar to those exhibited by sham lesioned rats. The second study demonstrated that 30 s intraoral infusions of sucrose (0.3 M), presented at 5 or 10 min intervals following an IP injection of LiCl (3.0 meq), resulted in conditioned changes in TRRs. These were characterized by orderly, gradual reductions in ingestive responses and increases in aversive responses. Finally, when area postrema lesioned rats (Study 3) were subjected to this conditioning procedure (brief sucrose presentations paired with the effects of LiCl) no evidence for conditioned or unconditioned changes in TRRs to sucrose were obtained. Lesioned rats injected with LiCl behaved similarly to sham lesioned rats injected with NaCl. These series of studies provide evidence indicating that the chemosensitive area postrema mediates the formation of conditioned palatability shifts induced by treatment with a toxin such as lithium. PMID:7770201

Ossenkopp, K P; Eckel, L A

1995-01-01

211

Ozone-induced adaptive and reactive cellular changes in respiratory bronchioles of bonnet monkeys  

Energy Technology Data Exchange (ETDEWEB)

To characterize the response of respiratory bronchioles (RBs) to chronic high ambient levels of ozone, bonnet monkeys were exposed for 90 days to 0, 0.4, or 0.64 ppm ozone (UV photometric standard; 3 monkeys/exposure). Morphologic changes in respiratory bronchiolar epithelium and interstitium were evaluated quantitatively at both the light and transmission electron microscopic levels. Significant changes in respiratory bronchioles following exposure included: a thicker wall and a narrower lumen, a thicker epithelial compartment and a much thicker interstitial compartment, shifts in epithelial cell populations with many more nonciliated bronchiolar epithelial cells and fewer squamous type I epithelial cells, larger nonciliated bronchiolar epithelial cells with a larger complement of cellular organelles associated with protein synthesis, greater amounts of both interstitial fibers and amorphous ground substance, greater numbers of interstitial smooth muscle cells per epithelial basal lamina surface area, and greater volumes of interstitial smooth muscle, macrophages, mast cells, and neutrophils per epithelial basal lamina surface area. These observations imply that chronic ozone exposure causes a concentration-dependent reactive peribronchiolar inflammatory response and an adaptive response consisting of hypertrophy and hyperplasia of the nonciliated bronchiolar cell.

Moffatt, R.K.; Hyde, D.M.; Plopper, C.G.; Tyler, W.S.; Putney, L.F.

1987-01-01

212

Changes in bone architecture during spinal fusion: three years follow-up and the role of cage stiffness.  

UK PubMed Central (United Kingdom)

STUDY DESIGN: A morphometrical analysis of microcomputed tomography-based reconstructions of bone from the fusion zone in spinal cages. OBJECTIVE: To describe the architectural changes of the fusing bone tissue in time and to study the effect of cage stiffness on the development of the bone architecture within the cage. SUMMARY OF BACKGROUND DATA: Interbody fusion within spinal cages is routinely evaluated as either successful or not successful. The quality of the fusion, however, strongly depends on the architecture (i.e., structure and density) of the bone tissue within the cage. Bone architecture obviously changes during the fusion process, and cage stiffness is known to play a pivotal role. METHODS: Nine bone samples were available from a long-term in vivo study on resorbable spinal cages in Dutch milk goats described elsewhere. Follow-up periods of 3, 6, 12, 24, 30, and 36 months were considered for cages made of titanium or Poly L-Lactic Acid. The specimens were scanned with a resolution of 13 microm in a microcomputed tomography system. From the resulting reconstructions, the bone density; trabecular thickness, spacing, and number; connectivity density; and structure model index were assessed. RESULTS: We found a homogenization of all bone structure indexes along the spinal axis with time, and remarkably faster in the Poly L-Lactic Acid cages than in the titanium cages. After longer follow-up periods, a coarser bone structure with larger trabecular thickness and intertrabecular spacing was found. The structure model index appeared to be sensitive for nonunions. CONCLUSIONS: More "mature" spinal fusions showed a coarser and more homogeneous bone structure. High cage stiffness had a deteriorating effect on the fusion rate. The structure model index appears to be an interesting parameter for quantifying the quality of bone in the fusion zone.

Smit TH; Müller R; van Dijk M; Wuisman PI

2003-08-01

213

Changes in trabecular bone microarchitecture in postmenopausal women with and without type 2 diabetes: a two year longitudinal study.  

UK PubMed Central (United Kingdom)

BACKGROUND: The risk of experiencing an osteoporotic fracture is greater for adults with type 2 diabetes despite higher than normal bone mineral density (BMD). In addition to BMD, trabecular bone microarchitecture contributes to bone strength, but is not assessed using conventional BMD measurement by dual x-ray absorptiometry (DXA). The aim of this study was to compare two year changes in trabecular bone microarchitecture in women with and without type 2 diabetes. METHODS: We used a 1 Tesla magnetic resonance imaging (MRI) scanner to acquire axial images (resolution 195 ?m × 195 ?m × 1000 ?m) of the distal radius. We report the change in the number and size of trabecular bone holes, bone volume fraction (BVTV), trabecular thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp), endosteal area, nodal and branch density for each group. Lumbar spine and proximal femur BMD were measured with DXA (Hologic, Discovery QDR4500A) at baseline and follow-up. Using a multivariable linear regression model, we evaluated whether the percent change in the trabecular bone microarchitecture variables differed between women with and without type 2 diabetes. RESULTS: Of the 54 participants at baseline with valid MRI image sets, 37 participants (baseline mean [SD] age, 70.8 [4.4] years) returned for follow-up assessment after 25.4 [1.9] months. Lumbar spine BMD was greater for women with diabetes compared to without diabetes at both baseline and follow-up. After adjustment for ethnicity, women with diabetes had a higher percent increase in number of trabecular bone holes compared to controls (10[1] % versus -7 [2]%, p=0.010), however results were no longer significant after adjustment for multiple comparisons (p=0.090). There were no differences in the change in other trabecular bone microarchitecture variables between groups. CONCLUSION: There were no differences in percent change in trabecular bone microarchitecture variables over two years in women with type 2 diabetes compared to women without diabetes. This study provides feasibility data, which will inform future trials assessing change in trabecular bone microarchitecture in women with type 2 diabetes. Larger studies using higher resolution imaging modalities that can assess change in trabecular and cortical bone compartments in women with type 2 diabetes are needed.

Pritchard JM; Giangregorio LM; Atkinson SA; Beattie KA; Inglis D; Ioannidis G; Gerstein H; Punthakee Z; Adachi JD; Papaioannou A

2013-01-01

214

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

2012-01-01

215

Bone changes in alcoholic cirrhosis of the liver. A histomorphometric study.  

UK PubMed Central (United Kingdom)

The effects of alcoholic liver cirrhosis on the calcium, calciotropic hormones (parathyroid hormone and 25 hydroxy vitamin D) and testosterone were examined in twenty men. A transiliac bone biopsy was performed in each patient. A double tetracycline labeling was done in 17 patients. Radiological signs of osteoporosis (crushed vertebrae and rib fractures) were rarely observed but a low trabecular bone volume (BV/TV) was consistently encountered (BV/TV = 14.2 +/- 4.6; normal 18.8 +/- 4.8; p less than .001). Osteomalacic signs were never observed in spite of very low calcium and 25 hydroxy vitamin D levels in the blood. Increased osteoclastic eroded surfaces (ES/BS = 8.1 +/- 5.2; normal 3.7 +/- 1.1; p less than .001) were not related with an hyperparathyroidism but a significant correlation was found with testosterone levels (r = .45; p less than .05). Histodynamic measurements indicate a drastically decreased osteoblastic activity with a very low bone formation rate (BFR/BS = .009 +/- .001; normal .0175 +/- .0125; p less than .001). This could explain the net increase of eroded surfaces and that osteomalacia cannot be observed even in the presence of profound calcium and vitamin D changes in alcoholics.

Chappard D; Plantard B; Fraisse H; Palle S; Alexandre C; Riffat G

1989-05-01

216

Changes in the structural composition and reactivity of Acer rubrum leaf litter tannins exposed to warming and altered precipitation: climatic stress-induced tannins are more reactive.  

UK PubMed Central (United Kingdom)

• Climate change could increase the frequency with which plants experience abiotic stresses, leading to changes in their metabolic pathways. These stresses may induce the production of compounds that are structurally and biologically different from constitutive compounds. • We studied how warming and altered precipitation affected the composition, structure, and biological reactivity of leaf litter tannins in Acer rubrum at the Boston-Area Climate Experiment, in Massachusetts, USA. • Warmer and drier climatic conditions led to higher concentrations of protective compounds, including flavonoids and cutin. The abundance and structure of leaf tannins also responded consistently to climatic treatments. Drought and warming in combination doubled the concentration of total tannins, which reached 30% of leaf-litter DW. This treatment also produced condensed tannins with lower polymerization and a greater proportion of procyanidin units, which in turn reduced sequestration of tannins by litter fiber. Furthermore, because of the structural flexibility of these tannins, litter from this treatment exhibited five times more enzyme (?-glucosidase) complexation capacity on a per-weight basis. Warmer and wetter conditions decreased the amount of foliar condensed tannins. • Our finding that warming and drought result in the production of highly reactive tannins is novel, and highly relevant to climate change research as these tannins, by immobilizing microbial enzymes, could slow litter decomposition and thus carbon and nutrient cycling in a warmer, drier world.

Tharayil N; Suseela V; Triebwasser DJ; Preston CM; Gerard PD; Dukes JS

2011-07-01

217

L-PRP diminishes bone matrix formation around autogenous bone grafts associated with changes in osteocalcin and PPAR-? immunoexpression.  

UK PubMed Central (United Kingdom)

Leucocyte- and platelet-rich plasma (L-PRP) is an autogenous platelet concentrate enriched with leukocytes that releases various growth factors responsible for the proliferation, regulation, and differentiation of mesenchymal cells during wound healing. Since the bone and medullary tissue are contiguous and share the same origin, this study evaluated the effect of L-PRP on the repair of calvaria bone using histomorphometric analysis of the newly formed bone, and compared the results in the presence of osteocalcin (OC) and peroxisome proliferator-activated receptor gamma (PPAR-?) detected by immunohistochemistry. Artificial circular bone defects (5mm diameter) were produced in the calvaria of 42 rats. The defects were treated with autograft, autograft combined with L-PRP, or without grafting material (sham). The animals were euthanized at 15 or 40 days postsurgery (n=7 in each group). Data obtained were analyzed by Student-Newman-Keuls test for histomorphometric and immunohistochemical interpretation. The development of bone matrix was significantly less in the defects treated with L-PRP, while the medullary area composed of fatty cells was larger. This coincided with the minor expression of OC and expressive presence of PPAR-?. These results suggest that L-PRP may impair osteoneogenesis and alter the ratio of differentiation between bone matrix and fatty cells, increasing the medullary tissue.

Portela GS; Cerci DX; Pedrotti G; Araujo MR; Deliberador TM; Zielak JC; Costa-Casagrande TA; Gonzaga CC; Giovanini AF

2013-08-01

218

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.)

1982-01-01

219

Findings of skin and bones in mastocytosis  

Energy Technology Data Exchange (ETDEWEB)

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

220

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

2010-01-01

 
 
 
 
221

BMD changes and predictors of increased bone loss in postmenopausal women after a 5-year course of alendronate.  

UK PubMed Central (United Kingdom)

Management of women discontinuing bisphosphonates after 3 to 5 years of treatment is controversial. Little is known about how much bone mineral density (BMD) is lost after discontinuation or whether there are risk factors for greater rates of bone loss post-discontinuation. We report patterns of change in BMD and prediction models for the changes in BMD in postmenopausal women during a 5-year treatment-free period after alendronate (ALN) therapy. We studied 406 women enrolled in the Fracture Intervention Trial (FIT) who had taken ALN for a mean of 5 years and were then enrolled in the placebo arm of the FIT Long-Term Extension (FLEX) trial for an additional 5 years, describing 5-year percent changes in total hip, femoral neck, and lumbar spine BMD over the treatment-free period. Prediction models of 5-year percent changes in BMD considered all linear combinations of candidate risk factors for bone loss such as BMD at the start of the treatment-free period, the change in BMD on ALN, age, and fracture history. Serum for three markers of bone turnover was available in 76 women, and these bone turnover markers were included as candidate predictors for these 76 women. Mean 5-year BMD changes were -3.6% at the total hip, -1.7% at the femoral neck, and 1.3% at the lumbar spine. Five-year BMD losses of >5% were experienced by 29% of subjects at the total hip, 11% of subjects at the femoral neck, and 1% of subjects at the lumbar spine. Several risk factors such as age and BMI were associated with greater bone loss, but no models based on these risk factors predicted bone loss rates. Although about one-third of women who discontinued ALN after 5 years experienced >5% bone loss at the total hip, predicting which women will lose at a higher rate was not possible.

McNabb BL; Vittinghoff E; Schwartz AV; Eastell R; Bauer DC; Ensrud K; Rosenberg E; Santora A; Barrett-Connor E; Black DM

2013-06-01

222

BMD changes and predictors of increased bone loss in postmenopausal women after a 5-year course of alendronate.  

Science.gov (United States)

Management of women discontinuing bisphosphonates after 3 to 5 years of treatment is controversial. Little is known about how much bone mineral density (BMD) is lost after discontinuation or whether there are risk factors for greater rates of bone loss post-discontinuation. We report patterns of change in BMD and prediction models for the changes in BMD in postmenopausal women during a 5-year treatment-free period after alendronate (ALN) therapy. We studied 406 women enrolled in the Fracture Intervention Trial (FIT) who had taken ALN for a mean of 5 years and were then enrolled in the placebo arm of the FIT Long-Term Extension (FLEX) trial for an additional 5 years, describing 5-year percent changes in total hip, femoral neck, and lumbar spine BMD over the treatment-free period. Prediction models of 5-year percent changes in BMD considered all linear combinations of candidate risk factors for bone loss such as BMD at the start of the treatment-free period, the change in BMD on ALN, age, and fracture history. Serum for three markers of bone turnover was available in 76 women, and these bone turnover markers were included as candidate predictors for these 76 women. Mean 5-year BMD changes were -3.6% at the total hip, -1.7% at the femoral neck, and 1.3% at the lumbar spine. Five-year BMD losses of >5% were experienced by 29% of subjects at the total hip, 11% of subjects at the femoral neck, and 1% of subjects at the lumbar spine. Several risk factors such as age and BMI were associated with greater bone loss, but no models based on these risk factors predicted bone loss rates. Although about one-third of women who discontinued ALN after 5 years experienced >5% bone loss at the total hip, predicting which women will lose at a higher rate was not possible. PMID:23408577

McNabb, Brian Louis; Vittinghoff, Eric; Schwartz, Ann V; Eastell, Richard; Bauer, Douglas C; Ensrud, Kristine; Rosenberg, Elizabeth; Santora, Arthur; Barrett-Connor, Elizabeth; Black, Dennis M

2013-06-01

223

Generalised morphoea with lichen sclerosus et atrophicus and unusual bone changes  

Directory of Open Access Journals (Sweden)

Full Text Available A 26-year-old male patient presented with multiple plaques on the limbs and trunk suggestive of morphoea. He also exhibited multiple, small, atrophic, hypopigmented macules on the left side of the trunk, the histopathology of which was consistent with lichen sclerosus et atrophicus (LSA). The patient developed large ulcers on the left leg and foot, and contractures with flexion deformity of the left ring and little fingers. This combination of generalised morphoea with LSA and unusual osteolytic bone changes is uncommon.

Prasad P; Padmavathy L; Sethurajan S; Kumar Prasanna; Rao Lakshman

1995-01-01

224

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

Energy Technology Data Exchange (ETDEWEB)

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.

Lee, Jae Seo; Kang, Byung Cheol [Chonnam National University College of Medicine, Gwangju (Korea, Republic of)

2005-09-15

225

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)

2010-01-01

226

Analysis of the results of reactivity change measurements on plutonium-uranium fuel elements  

International Nuclear Information System (INIS)

Reactivity change measurements have been carried out in the graphite-moderated reactor HECTOR on plutonium-uranium fuel elements with a low Pu240 content. The aim of the work was to develop a method in which measurements on small fuel samples (typically 18 in. long) could be used to check the validity of proposed methods of calculation for plutonium-bearing lattices. The experiments were carried out in a variety of lattices and demonstrated that, at a lattice pitch of 8.5 in. which was used for the majority of the measurements, the results were not significantly affected by the lattice environment. In particular, the results showed that it is not necessary to use plutonium-uranium fuel in the lattice surrounding the sample but that uranium fuel with similar properties is adequate. The accuracy obtained corresponded to an error of 0.5% in k? for a lattice containing the plutonium-uranium fuel. The results of the measurements were compared with the predictions of the TRACER method of lattice calculation. It was found that, at room temperature, there was no significant difference between the measured and calculated values of k? but that, at temperatures in the range 400-450 deg. C, the calculated value of k? was about 1 1/2% lower than the measured value. (author)

1964-01-01

227

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

228

Advanced age influences the dynamic changes in circulating C-reactive protein following injury.  

UK PubMed Central (United Kingdom)

BACKGROUND: The concentration of C-reactive protein (CRP), a biomarker of systemic inflammation, is determined by genetic, clinical and demographic factors including gender, smoking and body mass index (BMI). The influence of age on CRP dynamic changes following insult has, however, been poorly characterised. METHODS: We used unilateral hernia repair as a model of standardised insult to investigate the influence of baseline demographic and clinico-pathological factors affecting the dynamic changes in CRP, interleukin (IL) 6 and tumour necrosis factor-? over a time course of 48 h following injury. RESULTS: We derived CRP negativisation kinetics on 100 prospectively enrolled male subjects with mean age of 60.6 years (range 24-90 years) and mean BMI of 25.7 kg/m(2) (range 17.9-37 kg/m(2)). Patients who failed to normalise CRP to<10 mg/l at 48 h (n=74) were significantly older (p<0.001), had longer surgical times (p=0.05), higher waist/hip ratio (p=0.02). Multiple regression analysis confirmed age as the only independent predictor of delayed CRP normalisation (p=0.03). Persistent CRP elevation was associated with higher peak CRP values (p<0.001), higher IL-6 concentrations at 24 (p=0.01) and 48 h (p=0.03). CONCLUSIONS: CRP decline following insult is delayed in elderly patients as a result of unopposed IL-6 release. Age should be routinely incorporated in the assessment of CRP response to avoid misinterpretation of age-related delay in CRP clearance with ongoing systemic inflammation.

Pinato DJ; Bains J; Irkulla S; Pomroy J; Ujam B; Gaze D; Mendall MA

2013-08-01

229

Sequential changes in bone density before and after parathyroidectomy in primary hyperparathyroidism  

International Nuclear Information System (INIS)

[en] Bone density (bone mineral content/bone width) was determined by iodine-125 (125I)-photon absorptiometry in the distal third of the radius before and after successful parathyroidectomy in 37 patients with primary hyperparathyroidism. Bone density progressively declined during the two years immediately preceding surgery. It rose by 6.4% during the first year following surgery but remained stable thereafter. The results suggest that photon absorptiometry analysis of bone density may disclose continuing bone loss before surgery and may show a partial recovery of bone loss that may ensue after successful parathyroidectomy

1982-01-01

230

The impact of degenerative spinal changes on the correlation of peripheral and axial bone density  

International Nuclear Information System (INIS)

[en] Results of bone density measurements by quantitative computed tomography of the peripheral skeleton (pQCT) were compared with those of measurements at the axial skeleton with a view to study the effects of degenerative spinal changes on the validity of bone densitometry of the lumbar spine. 556 consecutive patients were examined by dual-energy X-ray absorptiometry (DXA) of the spine and by peripheral quantitative computed tomography (pQCT) of the distal radius. There were significant differences between the bone mineral values at the distal radius and those at the spine, depending on the degree of spinal degeneration. As expected, spinal degenerations showed a highly significant age dependence. With increasing degeneration the correlations between the radius total bone mineral concentration and the bone density of the lumbar spine decreased from r=0.45 to 0.23 in women and from r=0.64 to 0.28 in men. We conclude that the value of spinal DXA is reduced in patients with degenerative spinal disease, compared to the pQCT at the peripheral skeleton. (orig.)[de] Knochendichtemessungen mit der quantitativen Computertomographie am peripheren Skelett (pQCT) wurden mit Messungen der Knochendichte am Achsenskelett verglichen, um festzustellen, wie degenerative Veraenderungen an der Wirbelsaeule sich auf die Validitaet der Knochendichtemessungen an der Lendenwirbelsaeule auswirken. 556 aufeinanderfolgende Patienten wurden mit der Zweienergie-Roentgenabsorptiometrie (DXA) an der Wirbelsaeule und mit der peripheren quantitativen Computertomographie am Radius untersucht. Wir fanden in Abhaengigkeit vom Schweregrad degenerativer Veraenderungen signifikante Unterschiede zwischen den Knochendichtewerten am Radius und an der Wirbelsaeule. Wie zu erwarten war, zeigten die degenerativen Veraenderungen der Wirbelsaeule eine hochsignifikante Altersabhaengigkeit. Die Korrelationen zwischen der Gesamtdichte am Radius und der Knochendichte der Wirbelsaeule nahmen von r=0,45 auf r=0,23 bei den Frauen und von r=0,64 auf r=0,28 bei den Maennern ab. Unsere Ergebnisse zeigen, dass im Vergleich mit der pQCT am peripheren Skelett die DXA bei Patienten mit degenerativen Veraenderungen der Wirbelsaeule von eingeschraenktem Wert ist. (orig.)

1994-01-01

231

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

232

Computed microtomography and x-ray fluorescence analysis for comprehensive analysis of structural changes in bone.  

UK PubMed Central (United Kingdom)

This paper presents the results of a comprehensive analysis of structural changes in the caudal vertebrae of Turner's thick-toed geckos by computer microtomography and X-ray fluorescence analysis. We present algorithms used for the reconstruction of tomographic images which allow to work with high noise level projections that represent typical conditions dictated by the nature of the samples. Reptiles, due to their ruggedness, small size, belonging to the amniote and a number of other valuable features, are an attractive model object for long-orbital experiments on unmanned spacecraft. Issues of possible changes in their bone tissue under the influence of spaceflight are the subject of discussions between biologists from different laboratories around the world.

Buzmakov A; Chukalina M; Nikolaev D; Schaefer G; Gulimova V; Saveliev S; Tereschenko E; Seregin A; Senin R; Prun V; Zolotov D; Asadchikov V

2013-07-01

233

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 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 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 er (more) osion. 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.

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

2013-02-01

234

Using Reactive Transport Modeling to Understand Changes in Electrical Conductivity Associated with Bacterial Growth and Respiration  

Science.gov (United States)

Previous research has linked measured changes in the bulk electrical conductivity (?b) of water-saturated sediments to the respiration and growth of anaerobic bacteria. If the mechanism causing this signal is understood and characterized it could be used to identify and monitor zones of bacterial activity in the subsurface. The 1-D reactive transport model PHREEQC was used to understand ?b signals by modeling chemical gradients within two column reactors and corresponding changes in effluent chemistry. The flow-through column reactors were packed with Fe(III)-bearing sediment from Oyster, VA and inoculated with an environmental consortia of microorganisms. Influent in the first reactor was amended with 1mM Na-acetate to encourage the growth of iron-reducing bacteria. Influent in the second reactor was amended with 0.1mM Na-Acetate and 2mM NaNO3 to encourage the growth of nitrate-reducing bacteria. While effluent concentrations of acetate, Fe(II), NO3-, NO2-, and NH4+ remained at steady state, we measured a 3-fold increase (0.055 S/m - 0.2 S/m) in ?b in the iron-reducing column and a 10-fold increase in ?b (0.07 S/m - 0.8 S/m) in the nitrate-reducing column over 198 days. The ionic strength in both reactors remained constant through time indicating that the measured increases in ?b were not caused by changing effluent concentrations. PHREEQC successfully matched the measured changes in effluent concentrations for both columns when the reaction database was modified in the following manner. For the iron-reducing column, kinetic expressions governing the rate of iron reduction, the rate of bacterial growth, and the production of methane were added to the reaction database. Additionally, surface adsorption and cation exchange reactions were added so that the model was consistent with measured effluent chemistry. For the nitrate-reducing column, kinetic expressions governing nitrate reduction and bacterial growth were added to the reaction database. Additionally, immobile porosity was added along with adsorption and cation exchange reactions. Although the model revealed the existence of chemical and biological gradients within the columns that were not discernable as changes in effluent concentrations, none of the chemical reactions or gradients could explain the measured ?b increases in either column. This result is not consistent with chemical gradients within the column reactor causing the measured changes in ?b. To test the alternate hypothesis that microbial biofilms are electrically conductive, we used the output from PHREEQC to calculate the amount of biomass produced within the column reactors. If biofilm causes the ?b changes, our model is consistent with an electrical conductivity for biomass in the iron-reducing column between 2.75 and 220 S/m. The model is also consistent with an electrical conductivity for biomass in the nitrate-reducing column between 350 and 35,000 S/m. These estimates of biomass electrical conductivity are poorly constrained but represent a first step towards understanding the electrical properties associated with respiring biofilms.

Regberg, A. B.; Singha, K.; Picardal, F.; Brantley, S. L.

2011-12-01

235

Changes in vascular reactivity following administration of isoproterenol for 1 week: a role for endothelial modulation  

Science.gov (United States)

The aim of this study was to assess the effects of treatment with isoproterenol (ISO, 0.3?mg?kg?1?day?1, s.c.) for 7 days on the vascular reactivity of rat-isolated aortic rings. Additionally, potential mechanisms underlying the changes that involved the endothelial modulation of contractility were investigated. Treatment with ISO induced cardiac hypertrophy without changes in haemodynamic parameters. Aortic rings from ISO-treated rats showed an increase in the contraction response to phenylephrine (PHE) and serotonin, but did not change relaxations produced by acetylcholine or isoproterenol. Removal of the endothelium increased the responses to PHE in both groups. However, this procedure was less effective in ISO-treated as compared with control rats. Endothelial cell removal abolished the increase in the response to PHE in ISO-treated rats. The presence of N?-nitro-L-arginine methyl ester shifted the concentration–response curve to PHE to the left in both groups of rats. However, this effect was more pronounced in the ISO group. In addition, aminoguanidine (50??M) potentiated the actions of PHE only in the ISO group. ISO treatment increased nitric oxide synthase (NOS) activity and neuronal NOS and endothelial NOS protein expression in the aorta. Neither losartan (10??M) nor indomethacin (10??M) abolished the effects of ISO on the actions of PHE. Superoxide dismutase (SOD, 150?U?ml?1) and L-arginine (5?mM), but neither catalase (300?U?ml?1) nor apocynin (100??M), blocked the effect of ISO treatment. In addition, we observed an increase in superoxide anion levels as measured by ethidium bromide fluorescence and of copper and zinc superoxide dismutase protein expression in ISO-treated rats. In conclusion, our data suggest that ISO treatment alters the endothelial cell-mediated modulation of the contraction to PHE in rat aorta. The increased maximal response of PHE seems to be due to an increase in superoxide anion generation, which inactivates some of the basal NO produced and counteracts NO-mediated negative modulation even in the presence of high NO production and antioxidant defence.

Davel, Ana Paula C; Kawamoto, Elisa Mitiko; Scavone, Cristoforo; Vassallo, Dalton V; Rossoni, Luciana V

2006-01-01

236

[Bone structure and strength in the proximal femur - changes due to age and medical treatment].  

UK PubMed Central (United Kingdom)

Understanding bone strength scientifically requires knowledge of the material strength of a bone fragment, and understanding the bone strength of a specific part of a bone requires a destruction test using a cadaver bone. Since these tests cannot be used clinically, bone strength evaluation with the advanced medical technology of "predictive estimation of bone strength based on a finite element method using quantitative CT" has been developed to estimate bone strength with consideration of anatomical bone structure of the proximal femur. Today this method has come to be clinically applicable with actual patients. Investigations in our hospital have also led to the finding that while the proximal femur is strong enough for a standing load in daily life, it does not readily withstand the load from falls in accidents, and has a structure such that fractures may be predicted to occur at about one-third that size.

Harada A; Wakao N; Nemoto T

2013-07-01

237

[Bone structure and strength in the proximal femur - changes due to age and medical treatment].  

Science.gov (United States)

Understanding bone strength scientifically requires knowledge of the material strength of a bone fragment, and understanding the bone strength of a specific part of a bone requires a destruction test using a cadaver bone. Since these tests cannot be used clinically, bone strength evaluation with the advanced medical technology of "predictive estimation of bone strength based on a finite element method using quantitative CT" has been developed to estimate bone strength with consideration of anatomical bone structure of the proximal femur. Today this method has come to be clinically applicable with actual patients. Investigations in our hospital have also led to the finding that while the proximal femur is strong enough for a standing load in daily life, it does not readily withstand the load from falls in accidents, and has a structure such that fractures may be predicted to occur at about one-third that size. PMID:23811581

Harada, Atsushi; Wakao, Norimitsu; Nemoto, Tetsuya

2013-07-01

238

Bone mineral density changes in lactating adolescent mothers during the first postpartum year.  

UK PubMed Central (United Kingdom)

OBJECTIVES: This study aimed to compare changes in whole body bone mineral density (wbBMD) during the first postpartum year in adolescent mothers with those of nulliparous adolescents. METHODS: The study included 21 adolescent mothers and 16 nulliparous adolescent non-indigenous Mexican women (State of Sonora) from a low income level. All mothers were assessed at 15 days (0.5 months), 3 months, and 6 months postpartum; 16 were measured at 12 months postpartum. Nulliparous adolescents were assessed in the same periods. Multiple regression models was used to assess adjusted associations of changes in wbBMD (by DPX-MD+ densitometer) with dietary calcium and physical activity assessments (estimated using pre-tested questionnaires), post menarche years, and number of breast feedings. RESULTS: At baseline, no differences were observed between nulliparous and adolescent mothers regarding age, post-menarche years, or BMD values. Changes in wbBMD of -0.56% and 0.77% were observed in mothers and nulliparous adolescents, respectively, after the first 3 months (P = 0.006). Changes in wbBMD in mothers were associated with number of breast feedings and changes in BMI. At 12 months postpartum, the BMD of adolescent mothers was similar to that of nulliparous adolescents. CONCLUSIONS: At 1 year postpartum, adolescent mothers exhibited BMD similar to those of nulliparous adolescents. This result is likely attributable to the breastfeeding practices adopted by mothers during late adolescence. Am. J. Hum. Biol. 25:222-224, 2013. © 2013 Wiley Periodicals, Inc.

Méndez RO; Gallegos AC; Cabrera RM; Quihui L; Zozaya R; Morales GG; Valencia ME; Méndez M

2013-03-01

239

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)

[en] 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

1989-08-01

240

Effects of small-sided game and change-of-direction training on reactive agility and change-of-direction speed.  

UK PubMed Central (United Kingdom)

Abstract The purpose of this study was to determine the effects of training change-of-direction speed and small-sided games on performance in the Planned-AFL agility test and reactive agility. Twenty-five elite-standard U-18 Australian Rules football players were randomly allocated either to a change-of-direction group or a small-sided games group. Players participated in one or two 15-min sessions per week with 11 sessions conducted over a 7-week period during the season. Tests conducted immediately before and after the training period included the Planned-AFL agility test and a video-based reactive agility test specific to Australian Rules football. The reactive agility test variables were total time, decision time and movement response time. The small-sided games group improved total time (P = 0.008, effect size = 0.93), which was entirely attributable to a very large reduction in decision time (P < 0.001, effect size = 2.32). Small-sided games produced a trivial change in movement response time as well as in the Planned-AFL agility test (P > 0.05). The change-of-direction training produced small to trivial changes in all of the test variables (P > 0.05, effect size = 0-0.2). The results suggest that small-sided games improve agility performance by enhancing the speed of decision-making rather than movement speed. The change-of-direction training was not effective for developing either change-of-direction speed as measured by the Planned-AFL test or reactive agility.

Young W; Rogers N

2013-09-01

 
 
 
 
241

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(OH)D3), 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(OH)D3 was observed as early as after a 3-month weight loss therapy and during follow-up. In controls, serum 25(OH)D3 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.

Micha? Holecki; Barbara Zahorska -Markiewicz; Jerzy Chudek; Andrzej Wi?cek

2010-01-01

242

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; Deise Ponzoni; Jéssica Cerioli Munaretto; Adriana Corsetti; Mauro Gomes Trein Leite

2012-01-01

243

[The assessment of metabolism of bone tissue as changes in concentration of biochemical markers of bone turnover in inpatient alcohol dependent women].  

UK PubMed Central (United Kingdom)

AIM: The aim of this study was the assessment to of metabolism of bone tissue as changes in concentration of biochemical markers of bone turnover in inpatient alcohol dependent women. METHODS: The studied group consisted of 50 alcohol dependent female patients who were divided in two groups: one with an activity ofAST or ALT above referential values and level of bilirubin and the second one with the activity oftransaminases and level ofbilirubin within referential values. The level of sex hormones and markers of bone turnover such as osteocalcin and collagen cross laps (ctx) were indicated. RESULTS: In the group with an AST, ALT or BIL above referential values, the concentration of FSH in the ovulation phase and luteal phase as well as LH in luteal phase was significantly higher, while ctx and osteocalcin was lower compared to the group with AST, ALT or BIL within referential values. The mean concentrations ofFSH in follicular phase and luteal phase as well as LH in the luteal phase and progesterone in the follicular phase were increased in the group of patients with AST, ALT or BIL above referential values. The positive correlation between levels ofctx and osteocalcin was found which suggests a balance between processes. of bone formation and bone resorption in the whole group while a lack of such correlation was observed in patients with AST, ALT or BIL above referential values. CONCLUSIONS: The results obtained indicate the multidirectional and mutual relations between the alcohol abuse, liver function, bone turnover and activity of endocrine system.

Augusty?ska B; Araszkiewicz A; Wozniak A; Odrowaz-Sypniewska G; Gruszka M; Manysiak S; Wi?ko?? M; Kosmowski W

2013-01-01

244

Changes in megakaryocytes in cases of thrombocytopenia: bone marrow aspiration and biopsy analysis.  

UK PubMed Central (United Kingdom)

Background: Thrombocytopenia (platelet counts less than 150,000/?l) is commonly encountered in various hematological disorders including myelodysplastic syndromes as well as various non-myelodysplastic hematological conditions. Aim: The present study was undertaken to calculate the prevalence of various conditions associated with thrombocytopenia and to record the megakaryocytic alterations in various cases of thrombocytopenia. Apart from this by means of statistical analysis it was tried to analyze whether a significant difference existed in megakaryocytic alteration noted in myelodysplastic versus non- myelodysplastic conditions. Materials and Methods: A prospective series of 60 bone marrow aspirations along with concomitant bone marrow biopsies was conducted in a tertiary care centre catering to both urban as well as rural population in north India. Statistical Analysis: The distribution of morphological changes in cases of non myelodysplastic conditions and myelodysplastic were compared using Chi-Square test. A p-value less than 0.05 was considered significant. Results: The commonest cause of thrombocytopenia for which bone marrow examination was sought was dimorphic anaemia (18 cases, 30%), followed by myelodysplastic syndrome (06 cases, 10%) which was followed equally by acute lymphocytic leukemia and blast crisis of chronic myeloid leukemia (CML). Of all the non-MDS conditions apart from dimorphic anaemia, idiopathic thrombocytopenic purpura and chronic myeloid leukemia (blast crisis); megakaryocytic dysplastic forms were not noted in any other condition. In cases of myelodysplasia; dysplastic forms, bare megakaryocytic nuclei, hypogranular forms and micromegakaryocytes were seen. Comparison between frequencies of normal, high and low number of nuclear lobes among MDS (n=9) and non MDS (n=68) conditions were found to be statistically significant. Conclusion: Further studies on the evaluation of megakaryocytic alteration and their contribution to thrombocytopenia can provide growing knowledge to the pathogenesis of numerous hematopoietic disorders that may identify broader clinical applications of the newer strategies to regulate platelet count and functioning.

Bhasin TS; Sharma S; Manjari M; Mannan R; Kansal V; Chandey M; Piplani S

2013-03-01

245

Changes in Megakaryocytes in Cases of Thrombocytopenia: Bone Marrow Aspiration and Biopsy Analysis  

Science.gov (United States)

Background: Thrombocytopenia (platelet counts less than 150,000/?l) is commonly encountered in various hematological disorders including myelodysplastic syndromes as well as various non-myelodysplastic hematological conditions. Aim: The present study was undertaken to calculate the prevalence of various conditions associated with thrombocytopenia and to record the megakaryocytic alterations in various cases of thrombocytopenia. Apart from this by means of statistical analysis it was tried to analyze whether a significant difference existed in megakaryocytic alteration noted in myelodysplastic versus non- myelodysplastic conditions. Materials and Methods: A prospective series of 60 bone marrow aspirations along with concomitant bone marrow biopsies was conducted in a tertiary care centre catering to both urban as well as rural population in north India. Statistical Analysis: The distribution of morphological changes in cases of non myelodysplastic conditions and myelodysplastic were compared using Chi-Square test. A p-value less than 0.05 was considered significant. Results: The commonest cause of thrombocytopenia for which bone marrow examination was sought was dimorphic anaemia (18 cases, 30%), followed by myelodysplastic syndrome (06 cases, 10%) which was followed equally by acute lymphocytic leukemia and blast crisis of chronic myeloid leukemia (CML). Of all the non-MDS conditions apart from dimorphic anaemia, idiopathic thrombocytopenic purpura and chronic myeloid leukemia (blast crisis); megakaryocytic dysplastic forms were not noted in any other condition. In cases of myelodysplasia; dysplastic forms, bare megakaryocytic nuclei, hypogranular forms and micromegakaryocytes were seen. Comparison between frequencies of normal, high and low number of nuclear lobes among MDS (n=9) and non MDS (n=68) conditions were found to be statistically significant. Conclusion: Further studies on the evaluation of megakaryocytic alteration and their contribution to thrombocytopenia can provide growing knowledge to the pathogenesis of numerous hematopoietic disorders that may identify broader clinical applications of the newer strategies to regulate platelet count and functioning.

Bhasin, Tejinder Singh; Sharma, Sonam; Manjari, Mridu; Mannan, Rahul; Kansal, Vandana; Chandey, Manish; Piplani, Sanjay

2013-01-01

246

Multi-model prediction of climate-induced changes in ozone and reactive nitrogen fluxes into the troposphere  

Science.gov (United States)

Chemistry-Climate Models (CCMs) consistently predict a strengthening of the stratospheric Brewer-Dobson circulation due to climate change. The associated changes in the distribution of stratospheric ozone and reactive nitrogen will affect not only the flux of those tracers into the troposphere, but also the amount of ultra-violet radiation reaching the troposphere. While the contribution of stratospheric ozone to the total tropospheric ozone budget is only about 10%, it strongly affects ozone concentrations in the upper troposphere, where ozone has a relatively long lifetime (about one month) and its largest impact on radiative forcing. At the same time, changes in reactive nitrogen and UV radiation may influence the efficacy of chemical processes in the troposphere, and have adverse effects on human beings and the ecosystem. We present new results from a multi-model comparison of predicted changes in stratospheric ozone and reactive nitrogen fluxes using state-of-the-art CCMs, and the role of ozone depletion and recovery in modulating them. In order to gain confidence in the model predictions, we also evaluate the models’ capabilities to represent dynamical and chemical processes in the lower stratosphere through process-oriented diagnostics using both aircraft and satellite data.

Hegglin, M. I.; Shepherd, T. G.; Ccmval Modelling Team

2010-12-01

247

Glucocorticoid effects on changes in bone mineral density and cortical structure in childhood nephrotic syndrome.  

UK PubMed Central (United Kingdom)

The impact of glucocorticoids (GC) on skeletal development has not been established. The objective of this study was to examine changes in volumetric bone mineral density (vBMD) and cortical structure over 1 year in childhood nephrotic syndrome (NS) and to identify associations with concurrent GC exposure and growth. Fifty-six NS participants, aged 5 to 21 years, were enrolled a median of 4.3 (0.5 to 8.1) years after diagnosis. Tibia peripheral quantitative computed tomography (pQCT) scans were obtained at enrollment and 6 and 12 months later. Sex, race, and age-specific Z-scores were generated for trabecular vBMD (TrabBMD-Z), cortical vBMD (CortBMD-Z), and cortical area (CortArea-Z) based on >650 reference participants. CortArea-Z was further adjusted for tibia length-for-age Z-score. Quasi-least squares regression was used to identify determinants of changes in pQCT Z-scores. At enrollment, mean TrabBMD-Z (-0.54?±?1.32) was significantly lower (p?=?0.0001) and CortBMD-Z (0.73?±?1.16, p?change significantly over the study interval; however, CortArea-Z decreased (p?=?0.003). Greater GC dose (p?bone formation and greater secondary mineralization. Conversely, greater growth and expansion of CortArea-Z (ie, new bone formation) were associated with declines in CortBMD-Z. Greater linear growth was associated with impaired expansion of cortical area in NS. Studies are needed to determine the fracture implications of these findings.

Tsampalieros A; Gupta P; Denburg MR; Shults J; Zemel BS; Mostoufi-Moab S; Wetzsteon RJ; Herskovitz RM; Whitehead KM; Leonard MB

2013-03-01

248

Age-related changes in cortical bone mass: data from a German female cohort  

Energy Technology Data Exchange (ETDEWEB)

To describe data from digital radiogrammetry (DXR) in an unselected German female cohort over a wide age range. Using a retrospective study design we analyzed radiographs of the hand from 540 German women (aged 5-96 years) using an automated assessment of cortical thickness, metacarpal index (MCI), and estimated cortical bone mineral density (DXR-BMD) on digitized radiographs. Both hands were radiographed in 97 women. In this group DXR-BMD and cortical thickness were significantly higher in the right metacarpals while there was no significant difference in MCI. To study the association with age we differentiated young (<20 years), middle-aged (20-45 years), and an older patients (>45 years). In young women all parameters increased significantly with age in a linear fashion (r=0.8 for DXR-BMD, r=0.7 for MCI). In those aged 25-45 years DXR-BMD and MCI were highest (peak bone mass). In women aged 45 or older all parameters decreased with age in an almost linear fashion with an annual change ranging from 0.7% to 0.9%. Our results for an unselected German female cohort indicate that DXR is a reliable, widely available osteodensitometric technique based on the refinement of conventional radiogrammetry. These findings are comparable to those from other studies and represent a valid resource for clinical application and for comparisons with other ethnic groups. (orig.)

Toledo, V.A. Molina; Jergas, M. [St. Elisabeth-Krankenhaus, Department of Diagnostic and Interventional Radiology, Cologne (Germany)

2006-04-15

249

Prospective study of soft tissue contour changes following chin bone graft harvesting.  

UK PubMed Central (United Kingdom)

This study sought to evaluate changes in the soft tissue contour after chin bone graft harvesting. Thirty selected patients underwent chin bone graft harvesting and evaluations were made using lateral cephalograms preoperatively and postoperatively at 30 and 180 days. Fixed points and lines were established on cephalometric tracings and used to measure the selected vertical and sagittal parameters. Results showed statistically significant alterations to the vertical position values of the vermilion (V-VPV) which increased from 9.70 to 11.01 and the exposure of lower incisors (V-ELI) which increased from 1.85 to 3.5, showing an increase in their distance from the plane of reference and a lowering of their position, the clinical equivalent of a labial ptosis condition. None of the sagittal parameters analysed showed any statistically significant variation in the final evaluation. The study concluded that the alterations to patients' soft tissue contours resulted mainly from failure to ensure precise reattachment of the mentalis muscles and identified the need for further investigation of that aspect.

Nóia CF; Rodríguez-Chessa JG; Ortega-Lopes R; Cabral-Andrade V; Barbeiro RH; Mazzonetto R

2012-02-01

250

Participation of Bone Marrow-Derived Cells in Fibrotic Changes in Denervated Skeletal Muscle  

Science.gov (United States)

In denervated skeletal muscle, mononuclear interstitial cells accumulate in the perisynaptic regions before fibrotic change occurs. These cells are currently considered to be fibroblasts that originate from muscle tissue. However, when we denervated hind limbs of GFP-bone marrow chimeric mice by excising the sciatic nerve unilaterally, many bone marrow-derived cells (BM-DCs) infiltrated the interstitial spaces and accumulated in the perisynaptic regions, peaking 14 days after denervation. They accounted for nearly one-half of the increase in mononuclear interstitial cells. Although BM-DCs did not incorporate into satellite cells, immunohistochemical and FACS analyses revealed that BM-DCs were both CD45 and CD11b positive, indicating that they were of macrophage/monocyte lineage. BrdU staining showed inactive proliferation of BM-DCs. Reverse transcriptase-polymerase chain reaction of mononuclear cells isolated by FACS revealed that BM-DCs did not express type I collagen or tenascin-C; however, they did express transforming growth factor-?1, suggesting that they regulate the fibrotic process. In contrast, muscle tissue-derived interstitial cells expressed type I collagen and tenascin-C, suggesting that these populations were the final effectors of fibrosis. These findings identify elementary targets that may regulate the migration, homing, differentiation, and function of BM-DCs, leading to amelioration of the excessive fibrosis of denervated skeletal muscle.

Mochizuki, Yasushi; Ojima, Koichi; Uezumi, Akiyoshi; Masuda, Satoru; Yoshimura, Kotaro; Takeda, Shin'ichi

2005-01-01

251

Participation of bone marrow-derived cells in fibrotic changes in denervated skeletal muscle.  

UK PubMed Central (United Kingdom)

In denervated skeletal muscle, mononuclear interstitial cells accumulate in the perisynaptic regions before fibrotic change occurs. These cells are currently considered to be fibroblasts that originate from muscle tissue. However, when we denervated hind limbs of GFP-bone marrow chimeric mice by excising the sciatic nerve unilaterally, many bone marrow-derived cells (BM-DCs) infiltrated the interstitial spaces and accumulated in the perisynaptic regions, peaking 14 days after denervation. They accounted for nearly one-half of the increase in mononuclear interstitial cells. Although BM-DCs did not incorporate into satellite cells, immunohistochemical and FACS analyses revealed that BM-DCs were both CD45 and CD11b positive, indicating that they were of macrophage/monocyte lineage. BrdU staining showed inactive proliferation of BM-DCs. Reverse transcriptase-polymerase chain reaction of mononuclear cells isolated by FACS revealed that BM-DCs did not express type I collagen or tenascin-C; however, they did express transforming growth factor-beta1, suggesting that they regulate the fibrotic process. In contrast, muscle tissue-derived interstitial cells expressed type I collagen and tenascin-C, suggesting that these populations were the final effectors of fibrosis. These findings identify elementary targets that may regulate the migration, homing, differentiation, and function of BM-DCs, leading to amelioration of the excessive fibrosis of denervated skeletal muscle.

Mochizuki Y; Ojima K; Uezumi A; Masuda S; Yoshimura K; Takeda S

2005-06-01

252

Annual skeletal balance and metabolic bone marker changes in healthy early postmenopausal women: results of a prospective study.  

UK PubMed Central (United Kingdom)

The aim of this study was to establish the duration and annual rate of menopause-related bone loss and to investigate the relationship between bone turnover and bone loss in early healthy postmenopausal women. The rate of change in bone mineral density (BMD) at the lumbar spine and in bone turnover was measured twice at the exact interval of 12 months by dual-energy X-ray absorptiometry (DXA) and by the determination of plasma alkaline phosphatase levels (ALP) and fasting urinary hydroxyproline/creatinine ratio (OHPr/Cr), respectively, in 123 healthy premenopausal and postmenopausal women 45-60 years of age. The subjects were divided into nine groups according to their menstrual status and years since menopause (YSM). Annual bone loss at the lumbar spine of women who were menopausal for 1, 2, 3, 4, and 5 years was -2.62 +/- 0.37 (95% confidence interval -3.66, -1.58), -3.87 +/- 0.96 (-6.02, -1.73), -2.50 +/- 0. 37 (-3.29, -1.70), -2.86 +/- 0.73 (-4.44, -1.27), and -1.54 +/- 0.41 (-2.42, -0.66), respectively, and was significantly less than zero. But, the annual bone loss of women who were premenopausal or menopausal for 6, 7, and 8 years was -0.76 +/- 0.60 (-2.04, +0.53), -1.16 +/- 0.68 (-2.61, +0.29), 0.24 +/- 0.48 (-0.78, +1.26), and 0. 16 +/- 0.63 (-1.18, -1.49), respectively, and was not significantly different from zero. These results demonstrate that the early hormone-dependent bone loss commences in the first year after menopause and is arrested within 6 years after the onset of menopause. The overall bone loss for this phase is estimated to be approximately 15%. Annual change in ALP and OHPr/Cr seems to indicate that bone resorption prevails on bone formation in the first 2 YSM, whereas osteoblastic activity relatively prevails from YSM 3 to YSM 5, which explains the progressive repairing of the imbalance between bone resorption and formation.

Mazzuoli G; Acca M; Pisani D; Diacinti D; Scarda A; Scarnecchia L; Pacitti MT; D'Erasmo E; Minisola S; Bianchi G; Manfredi G

2000-04-01

253

Changes in bone alkaline phosphatase and procollagen type-1 C-peptide after static and dynamic exercises.  

UK PubMed Central (United Kingdom)

We investigated the effects of two types of nonweight-bearing exercise on changes in bone-specific alkaline phosphatase (BAP) and procollagen type 1 C-peptide (PIP). BAP is a specific marker of bone synthesis, whereas P1P reflects synthesis of type 1 collagen in other organs as well as bone. Eight participants performed static and dynamic unilateral knee extensions. BAP and PIP were measured before, and at 1, 2, 24, 48, and 72 hr after exercise. PIP increased at 24 hr after a static knee extension exercise, whereas BAP did not change during the experimental period. We found no changes in these markers after dynamic exercise. These results imply that type I collagen synthesis in tendons increases after static exercise.

Kubo K; Yuki K; Ikebukuro T

2012-03-01

254

Changes of bone density and serum osteocalcin levels in mid and late pregnancy  

International Nuclear Information System (INIS)

[en] Single photon bone densitometer has been used to determine the bone mineral contents in 1521 cases of mid and late pregnant women. The results showed that the contents are significantly lower than the normal group (P

1998-01-01

255

[The ultrastructural characteristics of the reactive changes in the cardiomyocytes of adult rats when cultured in vivo].  

UK PubMed Central (United Kingdom)

60 implantes of the left atrium myocardium were studied on the 1st, 3rd and 6th days of in vivo culture according to F. M. Lazarenko method (outbred laboratory male rats of 200-250g. body weight were used both as donors and recipients). Reactive changes of the cultured cardiomyocytes were assessed by methods of light and electron microscopy. Polymorphic nature of the cardiomyocyte reactive changes with the preservation of its tissue pecific determination was established. Myocardium implant did not form myosymplastic elements, cellular characteristics of organization remained in its implanted pieces. Data concerning degenerating and surviving cardiomyocytes are presented as well as those on cellular forms, identification of which is difficult on the ultrastructural level.

Stadnikov AA; Dedkov EI

1994-04-01

256

[The ultrastructural characteristics of the reactive changes in the cardiomyocytes of adult rats when cultured in vivo].  

Science.gov (United States)

60 implantes of the left atrium myocardium were studied on the 1st, 3rd and 6th days of in vivo culture according to F. M. Lazarenko method (outbred laboratory male rats of 200-250g. body weight were used both as donors and recipients). Reactive changes of the cultured cardiomyocytes were assessed by methods of light and electron microscopy. Polymorphic nature of the cardiomyocyte reactive changes with the preservation of its tissue pecific determination was established. Myocardium implant did not form myosymplastic elements, cellular characteristics of organization remained in its implanted pieces. Data concerning degenerating and surviving cardiomyocytes are presented as well as those on cellular forms, identification of which is difficult on the ultrastructural level. PMID:8718644

Stadnikov, A A; Dedkov, E I

257

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

2011-09-16

258

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

UK PubMed Central (United Kingdom)

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.

Tuljapurkar SR; McGuire TR; Brusnahan SK; Jackson JD; Garvin KL; Kessinger MA; Lane JT; O' Kane BJ; Sharp JG

2011-11-01

259

Changes of hyoid bone position following treatment of class II div1 malocclusion with Farmand functional appliance  

Directory of Open Access Journals (Sweden)

Full Text Available Background and Aim: Unlike other bones of the head and neck, hyoid bone has no bony articulations. It is connected to mandible, cranium and pharynx through muscles and ligaments. During treatment with functional appliance in patients with class II div1 malocclusion, mandible is positioned in inferior and anterior direction. Regarding the relation between hyoid and mandibular bone, alterations of hyoid bone position can be a result of functional appliance therapy. The aim of this study was to evaluate the changes of hyoid bone position following treatment with Farmand functional appliance in patients with class II div 1 malocclusion. Materials and Methods: In this before-after clinical trial, 28 patients with class II div 1 malocclusion which were under treatment with Farmand functional appliance for 11 months were selected. Facial growth in vertical, normal or horizontal direction was determined by cephalometric measurement. Data were analyzed with Paired-t test to compare the differences of mean values pre and post treatment. Variance analysis was used to compare the three growth patterns. P<0.05 was considered as the limit of significance. Results: Hyoid bone shifted significantly forward in horizontal dimension (P<0.01) and non-significantly upward in vertical dimension. There was no significant difference among the three studied groups with respect to hyoid bone position alterations in horizontal dimension but significant difference was observed between horizontal and vertical growth pattern in vertical dimension (P<0.05). There was significant correlation between decrease of ANB angle and forward movement of hyoid bone. Conclusion: Based on the results of this study, treatment with Farmand functional appliance (Fa II) leads to significant alterations in the position and anterior displacement of the hyoid bone.

Yassaei S; Soroush MM

2007-01-01

260

Magnetic resonance imaging of bone marrow changes in Gaucher disease during enzyme replacement therapy: first German long-term results  

Energy Technology Data Exchange (ETDEWEB)

Objective:. Since 1991, enzyme replacement therapy (ERT) has been available for patients with Gaucher disease in Germany. The aim of this study was to analyse the MR pattern of bone marrow involvement and response to ERT in Gaucher disease type I. Patients and design:. Thirty patients with Gaucher disease type I had MRI examinations prior to initiation of ERT with alglucerase/imiglucerase and during follow-up. Median MR follow-up and duration of ERT were 36 months. Coronal T1- and T2-weighted spin-echo images of the lower extremities were obtained to evaluate changes in the appearance of yellow marrow. MR images were categorized as having either a homogeneous (type A) or non-homogeneous patchy (type B) appearance of bone involvement and response to ERT was assessed by two radiologists. Results:. Overall, 19 of 30 patients (63%) showed an increased signal intensity on T1- and T2-weighted images after 36 months of ERT, consistent with partial reconversion of fatty marrow during treatment. Focal bone lesions surrounded by a low signal intensity (SI) rim did not respond to ERT, suggesting bone infarcts. Of the 11 patients with bone infarcts (low SI rim lesion), 82% had the non-homogeneous type B pattern (P=0.0021). In 86% of patients with splenectomy, bone infarcts were seen (P<0.05). Conclusions:. MRI using T1- and T2-weighted spin-echo sequences is a valuable, non-invasive method for monitoring bone marrow response in patients receiving ERT. A non- homogeneous patchy signal intensity of bone marrow involvement correlates with the presence of bone infarcts (P=0.0021). (orig.)

Poll, L.W.; Koch, J.A.; Scherer, A.; Boerner, D.; Moedder, U. [Duesseldorf Univ. (Germany). Inst. fuer Diagnostische Radiologie; Dahl, S. vom; Niederau, C.; Haeussinger, D. [Duesseldorf Univ. (Germany). Medizinische Fakultaet; Willers, R. [Duesseldorf Univ. (Germany). Rechenzentrum

2001-09-01

 
 
 
 
261

Changing manifestations of brown tumors on bone scan in renal osteodystrophy  

International Nuclear Information System (INIS)

In a patient with chronic renal failure and secondary hyperparathyroidism, brown tumors, visualized initially as photon-deficient areas on bone scintigraphy, reverted to areas of abnormally increased activity following parathyroidectomy. This dual appearance on bone scan paralleled the functional state of the parathyroid gland. The possible relationship of hyperphosphatemia to the increased bone-scan activity noted in the calvarium, mandible, and facial bones is discussed

1978-01-01

262

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)

1980-01-01

263

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

2005-01-01

264

[The effects of oxygen partial pressure changes on the osteometric markers of the bone tissue in rats].  

Science.gov (United States)

Our purpose was to investigate the oxygen partial pressure changes on the osteometric and biochemical markers of bone tissue in rats. It was shown that breathing of altered gas mixture did not change the mass, general length, sagittal diameter and density thigh-bones in 12-month Wistar male-rats. The dosed normobaric hypoxia increased the activity of alkaline phosphatase and decreased the activity of tartrate-resistant acid phosphatase. At the same time normobaric hyperoxia with 40 and 90% oxygen conversely decreased the activity of alkaline phosphatase and increased the activity of tartrate-resistant acid phosphatase. PMID:23821937

Berezovs'ky?, V Ia; Zamors'ka, T M; Ianko, R V

2013-01-01

265

[The effects of oxygen partial pressure changes on the osteometric markers of the bone tissue in rats].  

UK PubMed Central (United Kingdom)

Our purpose was to investigate the oxygen partial pressure changes on the osteometric and biochemical markers of bone tissue in rats. It was shown that breathing of altered gas mixture did not change the mass, general length, sagittal diameter and density thigh-bones in 12-month Wistar male-rats. The dosed normobaric hypoxia increased the activity of alkaline phosphatase and decreased the activity of tartrate-resistant acid phosphatase. At the same time normobaric hyperoxia with 40 and 90% oxygen conversely decreased the activity of alkaline phosphatase and increased the activity of tartrate-resistant acid phosphatase.

Berezovs'ky? VIa; Zamors'ka TM; Ianko RV

2013-01-01

266

Relations between the hydrogenolysis reactivities and the structural changes of coals induced by thermal or hydrothermal treatment  

Energy Technology Data Exchange (ETDEWEB)

The relationship between the hydrogenolysis reactivities and structural changes of coals induced by hydrothermal treatment were investigated and compared with those of dry thermal treatment. The solvent effects of water on the upgrading reaction of coal liquefaction residue are discussed in order to clarify interactions between water and coal molecules. Cross-linking formations among the acidic groups in coals were inhibited during the hydrothermal treatment. 5 refs., 2 figs., 2 tabs.

Sugano, M.; Ochiai, H.; Mashimo, K. [Nihon University, Tokyo (Japan). College of Science and Technology

1999-07-01

267

Change in CANDU-6 reactivity following a power reduction at low PHT purity  

International Nuclear Information System (INIS)

The reactivity effect of a power reduction in CANDU-6 is examined using a three-dimensional, steady-state, coupled neutronics/thermalhydraulics methodology, starting from a global irradiation distribution matched to site data. The power reduction is sufficient to suppress coolant boiling in the fuel channels, and thus the significant parameters affecting reactivity are an increase in coolant density and a decrease in fuel temperature. These individual components are estimated using infinite-lattice-cell methodology. The effect of using newer methodology, particularly for the thermalhydraulic analysis, is examined by comparison with previous simulations. (author). 10 refs., 7 tabs., 1 fig.

1995-01-01

268

Quantification of age-related changes in the structure model type and trabecular thickness of human tibial cancellous bone.  

UK PubMed Central (United Kingdom)

Structure model type and trabecular thickness are important characteristics in describing cancellous bone architecture. It has been qualitatively observed that a radical change of trabeculae from plate-like to rod-like occurs in aging, bone remodeling, and osteoporosis. Thickness of trabeculae has traditionally been measured using model-based histomorphometric methods on two-dimensional (2-D) sections. However, no quantitative study has been published based on three-dimensional (3-D) methods on the age-related changes in structure model type and trabecular thickness for human peripheral (tibial) cancellous bone. In this study, 160 human proximal tibial cancellous bone specimens from 40 normal donors, aged 16 to 85 years, were collected. These specimens were micro-computed tomography (micro-CT) scanned, then the micro-CT images were segmented using optimal thresholds. From accurate 3-D data sets, structure model type and trabecular thickness were quantified by means of novel 3-D methods. Structure model type was assessed by calculating the structure model index (SMI). The SMI was quantified based on a differential analysis of the triangulated bone surface of a structure. This technique allows quantification of structure model type, such as plate, rod objects, or mixture of plates or rods. Trabecular thickness is calculated directly from 3-D images, which is especially important for an a priori unknown or changing structure. Furthermore, 2-D trabecular thickness was also calculated based on the plate model. Our results showed that structure model type changed towards more rod-like in the elderly, and that trabecular thickness declined significantly with age. These changes become significant after 80 years of age for human tibial cancellous bone, whereas both properties seem to remain relatively unchanged between 20 and 80 years. Although a fairly close relationship was seen between 3-D trabecular thickness and 2-D trabecular thickness, real 3-D trabecular thickness was significantly underestimated using 2-D method.

Ding M; Hvid I

2000-03-01

269

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

International Nuclear Information System (INIS)

[en] 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

1981-01-01

270

Rate of bone density change does not enhance fracture prediction in routine clinical practice.  

UK PubMed Central (United Kingdom)

CONTEXT: There is contradictory information on whether the rate of bone mineral density (BMD) loss is an independent risk factor for osteoporotic fractures and whether this should be included in fracture prediction systems. OBJECTIVE: This study was undertaken to better define rate of BMD loss as a contributor to fracture risk in routine clinical practice. DESIGN AND SETTING: We performed a retrospective cohort study using a database of all clinical BMD results for the province of Manitoba, Canada. PATIENTS: We included 4498 untreated women age 40 yr and older at the time of a second BMD test performed between April 1996 and March 2009. MAIN OUTCOME MEASURES: A total of 146 women with major osteoporotic fracture outcomes after the second BMD test (mean observation, 2.7 yr) and relevant covariates were identified in population-based computerized health databases. RESULTS: Annualized percentage change in total hip BMD was no greater in fracture compared to nonfracture women (-0.4 ± 1.7 vs. -0.5 ± 1.4; P = 0.166). After adjustment for final total hip BMD, other covariates, and medication use, rate of total hip BMD change did not predict major osteoporotic fractures (hazard ratio, 0.95 per sd decrease; 95% confidence interval, 0.81-1.10). Similar results were also seen in analyses based upon change in lumbar spine and femoral neck BMD. CONCLUSIONS: We found no evidence that BMD loss, as detected during routine clinical monitoring, was a significant independent risk factor for major osteoporotic fractures.

Leslie WD; Morin SN; Lix LM

2012-04-01

271

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

Directory of Open Access Journals (Sweden)

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

272

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.)

1988-01-01

273

Changes in hyperfrontality of cerebral blood flow and carbon dioxide reactivity with age  

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We evaluated the topographic distributions of regional cerebral blood flow in 51 normal subjects (mean age 41 years) by the xenon-133 inhalation technique. Forty-five of these subjects were divided by age into young normals less than 30 years old (mean age 24 years), middle-aged normals 30-50 years old (mean age 40 years), and elderly normals greater than 50 years old (mean age 62 years); there were 15 subjects in each group. The distributions of vascular CO2 reactivity to hypocapnia were also evaluated in 20 of the normal subjects (mean age 34 years), including 11 younger normals less than 30 years old (mean age 24 years) and nine older (middle-aged or elderly) normals greater than or equal to 30 years old (mean age 45 years). The hyperfrontal distribution of regional cerebral blood flow observed in the young and middle-aged normals was not observed in the elderly normals. The hyperfrontal distribution of vascular CO2 reactivity observed in the younger normals was absent in the older normals. In addition, the correlation between regional cerebral blood flow and vascular CO2 reactivity observed in the younger normals was disturbed in the older normals. The data show a hyperfrontal distribution of regional cerebral blood flow in normal subjects that diminishes during the fifth and sixth decades, along with a distribution of vascular CO2 reactivity in younger normal subjects that is not homogeneous throughout the frontoparietal regions.

Tsuda, Y.; Hartmann, A. (Neurological Univ. Clinic, Bonn (Germany, F.R.))

1989-12-01

274

Epidemiology of Paget's disease of bone: a systematic review and meta-analysis of secular changes.  

UK PubMed Central (United Kingdom)

CONTEXT: Several studies have suggested that the prevalence and severity of PDB have fallen in recent years. The magnitude of this trend and its globalization have not been well established. OBJECTIVE: The objective of this study is to estimate the pooled magnitude of the changes in the prevalence of PDB and as a secondary objective, to make up a world atlas of PDB prevalence. METHODS: A systematic review of English and non-English articles using MEDLINE (1946 to 2013) and EMBASE (1980 to 2013) was the method used. Search terms included epidemiology, incidence, prevalence, cohort studies, osteitis deformans or Paget's disease of bone. Studies with incidence and/or prevalence rate for PDB were included. Two authors independently extracted the data using predefined data fields and quality assessment. A pooled analysis based on random-effects models was carried out for secular trends. RESULTS: Twenty-eight articles documented the prevalence of PDB; four articles the incidence and two articles the rate of new referrals. The prevalence of PDB varied greatly between the different countries, from 0.00028% in Japan to 5.4% in the UK. There were available data on changes in prevalence from two different surveys over two different time frames in Europe and New Zealand. In all but one city (Turin), a drop in the prevalence of PDB was recorded (pooled OR 0.64; 95% CI 0.45-0.91). CONCLUSION: The incidence and prevalence rates of PDB vary widely between populations but both have decreased in most regions over recent years. The changes are heterogeneous however and within countries, the largest changes have been in areas that previously had a high prevalence. The reasons for these changes remain unclear at present but are likely to be due to an interaction between genetic factors and environmental triggers which may differ in different regions.

Corral-Gudino L; Borao-Cengotita-Bengoa M; Del Pino-Montes J; Ralston S

2013-08-01

275

Magnetic resonance imaging of bone marrow changes in Gaucher disease during enzyme replacement therapy: first German long-term results  

International Nuclear Information System (INIS)

Objective:. Since 1991, enzyme replacement therapy (ERT) has been available for patients with Gaucher disease in Germany. The aim of this study was to analyse the MR pattern of bone marrow involvement and response to ERT in Gaucher disease type I. Patients and design:. Thirty patients with Gaucher disease type I had MRI examinations prior to initiation of ERT with alglucerase/imiglucerase and during follow-up. Median MR follow-up and duration of ERT were 36 months. Coronal T1- and T2-weighted spin-echo images of the lower extremities were obtained to evaluate changes in the appearance of yellow marrow. MR images were categorized as having either a homogeneous (type A) or non-homogeneous patchy (type B) appearance of bone involvement and response to ERT was assessed by two radiologists. Results:. Overall, 19 of 30 patients (63%) showed an increased signal intensity on T1- and T2-weighted images after 36 months of ERT, consistent with partial reconversion of fatty marrow during treatment. Focal bone lesions surrounded by a low signal intensity (SI) rim did not respond to ERT, suggesting bone infarcts. Of the 11 patients with bone infarcts (low SI rim lesion), 82% had the non-homogeneous type B pattern (P=0.0021). In 86% of patients with splenectomy, bone infarcts were seen (P

2001-01-01

276

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

277

Quantitative analysis of alveolar bone change following implant placement using intraoral radiographic subtraction  

International Nuclear Information System (INIS)

The purpose of this study was to develop a procedure for quantitative analysis using intraoral radiographs of alveolar bone after placement of dental implants and to consider the validity of the method. We evaluated the ten patients (2 males and 8 females, average age: 48.4 years-old), who were treated with dental implant operation in the site of mandibular molar region, since October of 1999 until September of 2000 in Kimura Dental Clinic (Kumamoto, Japan). We evaluated the intraoral radiographs taken pre- and post- operatively and at follow-up examination. To detect alveolar bone change on radiograph, we adopted the digital subtraction method. Although the radiographs were taken under an ordinary technique with cone indicator, we did not apply the standardized technique with fixing material customized for each patient. Therefore, we used geometric correction and density compensation before subtraction. We assessed the basic statistical values (mean, variance, kurtosis and skewness) of the region of interest (ROI) of the subtracted images. Also, we noted PPD (probing pocket depth) and BOP (bleeding on probing) at each site as indicators of clinical findings and all implanted sites were classified according to the PPD or BOP, i.e. PPD increased group ''PPD (+)'' and PPD stable group ''PPD (-)'', likewise BOP positive group ''BOP (+)'' and negative group ''BOP (-)''. We considered the statistical values of ROI in each group and compared these findings. Mean and variance values of PPD (+) were higher than those of PPD (-) and there was a significant difference in mean value (p=0.031). Similarly, mean and variance values of BOP (+) were statistically higher than those of BOP (-) (p=0.041 and p=0.0087, respectively). Concerning kurtosis and skewness, there was no difference between PPD (+) and PPD (-), or between BOP (+) and BOP (-). Using our method, the radiographs taken for follow-up examination could be assessed quantitatively. It is suggested that geometric correction and density compensation could abbreviate the standardized intraoral radiographic technique prepared for subtraction. (author)

2002-01-01

278

An Investigation of the Efficacy of Cuttlefish Bone Powder in the Removal of Reactive Blue 19 Dye from Aqueous Solutions: Equilibrium and Isotherm Studies  

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Full Text Available Introduction: Discharge of textile wastewater causes the reduction of sunlight penetration, interferes with the receiving waters ecology and damage the environment. The aim of this study was to determine the removal efficiency of reactive blue 19 dye from aqueous solutions by cuttlefish bone powder. Materials & Methods: This study was performed experimentally and in laboratory scale. In this research, the effect of adsorbent dose, contact time, initial dye concentration and pH was evaluated. Dye concentration in unknown samples was determined by UV/Vis spectrophotometer. In order to better understand the adsorption process, the experimental data were analysed with Langmuir and Freundlich isotherm models. Results: Results showed that increasing the adsorbent dose up to 0.4 gr/100ml and increasing of contact time, led to an increase in the efficiency of dye removal. Increasing the initial pH had no effect on the adsorption efficiency and increasing the initial concentration of dye decreased the removal efficiency. The Removal efficacy of the dye was found to be 60%, 45%, 37.5% and 31.9% at the time interval of 3h and the initial dye concentrations of 25, 50, 75 and 100 mg/l, respectively. The experimental data were in good concordance with Langmuir isotherm model (R2=0.993). Conclusion: Cuttlefish bone powder is a natural and inexpensive adsorbent that can be used for the removal of environmental contaminations. The adsorption process is affected by sorbent dose, initial dye concentration and contact time but pH had no significant effect on removal efficiency

Mohammad Taghi Ghaneian; Mojtaba Momtaz; Mahboobeh Dehvari

2012-01-01

279

Diagnostic accuracy of the detection of bone change using panoramic TMJ projection. Comparative study with limited cone-beam CT  

International Nuclear Information System (INIS)

[en] Panoramic temporoman joint (TMJ) projection is one of the alternative methods of conventional radiography, such as transcranial projection, for diagnosing temporomandibular joint disorder. There have been a few reports describing the diagnostic ability of this method. We evaluated the diagnostic accuracy of detecting bone change with panoramic TMJ projection. Fifty TMJs in 25 patients were examined. All TMJs were examined by panoramic TMJ projection (Hyper XF) and limited cone-beam CT (3D Accuitomo FPD; 3DX). Two observers evaluated the presence of bone change in the TMJ region using panoramic TMJ projection. One other observer evaluated the limited cone-beam CT for the presence and the pattern of bone changes in the TMJ region as the gold standard. Panoramic TMJ findings were evaluated with regard to sensitivity, specificity, and accuracy. Sensitivity, specificity and accuracy of the panoramic TMJ projection were 0.86, 0.76, and 0.82, respectively. These results and those of previous reports on other radiographic methods for TMJ suggest that panoramic TMJ projection is a useful method of screening for bone change due to TMJ disorder. (author)

2008-01-01

280

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 r...

Kornaat, Peter R.; Kloppenburg, Margreet; Sharma, Ruby; Botha-Scheepers, Stella A.; Le Graverand, Marie-Pierre Hellio

 
 
 
 
281

The changes in plasma serotonin levels after hormone therapy and their relationship with estrogen responsiveness on bone in postmenopausal women.  

UK PubMed Central (United Kingdom)

CONTEXT: Selective serotonin reuptake inhibitors have shown to be associated with an increased risk of fractures. It has been suggested that circulating serotonin is an important regulatory factor and that estrogen may regulate bone metabolism through the serotonin pathway. OBJECTIVE: Our objective was to determine the association between plasma serotonin level and bone turnover before and after hormone therapy (HT) in postmenopausal women. PARTICIPANTS AND DESIGN: In this parallel comparative study using age-matched controls, 80 postmenopausal women (21 control, 59 receiving HT) aged 46-64 yr were assessed. The plasma levels of serotonin, serum concentrations of osteocalcin and carboxyterminal telopeptides, and bone mineral density (BMD) were measured at baseline and after 3 months and 1 yr of HT. RESULTS: The plasma serotonin level was significantly correlated with serum total alkaline phosphatase level at baseline (r = -0.223, P = 0.048) but not with serum osteocalcin (r = -0.217, P = 0.056) or carboxyterminal telopeptides (r = -0.217, P = 0.054). There was no significant association between baseline serotonin and BMD measured at the spine or femur. The median decrements of circulating serotonin from baseline were -9.3% (interquartile range -34.0 to 53.6%) and -7.2% (-25.5 to 64.5%) at 3 months and 1 yr of HT, respectively. These changes were not significantly different from those in the control group. The short-term changes of circulating serotonin at 3 months after HT did not show significant association with the changes in BMD measured at the lumbar spine or proximal femur 1 year after HT. CONCLUSIONS: Our results suggest that circulating serotonin may reflect bone turnover status, but it is not a strong enough predictor of bone loss to use as a bone marker. Moreover, serial measurements of plasma serotonin after short-term treatment with estrogen cannot predict the long-term responsiveness of bone to estrogen, suggesting that the bone-preserving effect of estrogen is independent of the peripheral action of serotonin on bone.

Kim HY; Park MH; Yoon HK; Han KO

2012-06-01

282

Changed reactivity of the 1-bromo-4-nitrobenzene radical anion in a room temperature ionic liquid.  

UK PubMed Central (United Kingdom)

Radical anions of 1-bromo-4-nitrobenzene (p-BrC6H4NO2) are shown to be reactive in the room temperature ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, ([C4mPyrr][NTf2]), by means of voltammetric measurements. In particular, they are shown to react via a DISP type mechanism such that the electrolysis of p-BrC6H4NO2 occurs consuming between one and two electrons per reactant molecule, leading to the formation of the nitrobenzene radical anion and bromide ions. This behaviour is a stark contrast to that in conventional non-aqueous solvents such as acetonitrile, dimethyl sulfoxide or N,N-dimethylformamide, which suggests that the ionic solvent promotes the reactivity of the radical anion, probably via stabilisation of the charged products.

Ernst S; Ward KR; Norman SE; Hardacre C; Compton RG

2013-05-01

283

Changes of lymphocyte subsets in leukemia patients who received allogenic bone marrow transplantation.  

Directory of Open Access Journals (Sweden)

Full Text Available Proportional changes of lymphocyte subsets in the peripheral blood were monitored by two-color flow-cytometry in seven leukemia patients who had received allogenic bone marrow transplantation (BMT). Lymphocyte counts, and proportions of T and B-cells returned to normal ranges between the 2nd and 12th months after BMT. Activated T-cells prominently increased after BMT, and the values gradually returned toward normal. As to lymphocyte subsets, the proportions of CD 4+ cells had remained low, while those of CD 8+ cells high for a whole observation period after BMT. The changes of CD 4+ cells were caused by the decrease of suppressor-inducer T-cells (CD 4+ Leu 8+). High proportion of CD 8+ cells was mainly associated with increased suppressor T-cells (CD 8+ CD 11+). Among natural killer (NK) cells, highly active NK cells (CD 16+ CD 57-) markedly increased shortly after BMT, and gradually returned to normal. CD 16 -CD 57+ NK cells increased beyond normal ranges after the 2nd month. The incidence or degree of acute and chronic graft-versus-host diseases (GVHD) did not correlate with the changes of any lymphocyte subsets. The present results suggest that the increase of activated T-cells shortly after BMT reflects lymphocyte reconstitution. The prolonged immune deficiency after BMT might be related to either deficient expression of homing receptor (Leu 8 antigen) on CD 4+ cells or increased suppressor T-cells (CD 8+ CD 11+). In addition, the early increase of NK cells after BMT may compensate for the immune deficiency in BMT patients.

Komatsuda,Mitsumoto

1991-01-01

284

Hormone predictors of bone mineral density changes during the menopausal transition.  

UK PubMed Central (United Kingdom)

UNLABELLED: OBJECTIVE AND CONTEXT: Our objective was to examine predictability of reproductive hormone concentrations for bone mineral density (BMD) loss during the menopausal transition. DESIGN: We conducted a longitudinal (five annual examinations), multiple-site (n = 5) cohort study, the Study of Women's Health Across the Nation (SWAN). PARTICIPANTS: Participants included, at baseline, 2311 premenopausal or early perimenopausal African-American, Caucasian, Chinese, and Japanese women. MAIN OUTCOME MEASURES: We assessed annual dual-energy x-ray absorptiometry lumbar spine and total hip BMD measures, with endogenous estradiol (E2), FSH, androgens, and self-reported menstrual bleeding patterns. RESULTS: Over the 4-yr period, lumbar spine BMD loss was 5.6% in natural postmenopause, 3.9% in surgical postmenopause, or 3.2% in late perimenopause. Baseline FSH concentrations, subsequent FSH levels, and their interaction predicted 4-yr BMD loss. If baseline FSH was less than 25 mIU/ml, higher follow-up FSH (>70 mIU/ml) predicted a 4-yr spine BMD loss of -0.05 g/cm(2). If baseline FSH values were more than 35-45 mIU/ml, lower follow-up FSH (i.e. 40-50 mIU/ml) predicted a -0.05 g/cm(2) 4-yr spine BMD loss. Charts show amounts of predicted BMD losses with combinations of baseline FSH values and FSH levels over time. E2 concentrations less than 35 pg/ml were associated with lower BMD, but annual E2 measures and changes did not predict BMD loss. Testosterone, free androgen index, and dehydroepiandrosterone sulfate concentrations were not significantly associated with BMD loss. CONCLUSIONS: Spine and hip BMD losses during the menopause transition were most strongly related to the interaction between initial FSH levels and longitudinal FSH changes and not to E2 or androgen levels or changes.

Sowers MR; Jannausch M; McConnell D; Little R; Greendale GA; Finkelstein JS; Neer RM; Johnston J; Ettinger B

2006-04-01

285

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.

2001-01-01

286

MRI signal changes of the bone marrow in HIV-infected patients with lipodystrophy: correlation with clinical parameters  

International Nuclear Information System (INIS)

To assess the prevalence, imaging appearance, and clinical significance, of bone marrow MR signal changes in a group of human immunodeficiency virus (HIV)-infected patients with lipodystrophy syndrome. Twenty-eight HIV-infected patients with lipodystrophy syndrome treated with highly active antiretroviral therapy, and 12 HIV-negative controls underwent MRI of the legs. Whole-body MRI, SPECT/CT, and a complete radiographic skeletal survey were obtained in subjects with signal changes in bone marrow. MRI and clinical evaluations were reviewed 6 months after baseline to determine changes after switching from thymidine analogs (TA) to tenofovir-DF (TDF). MRI results correlated with clinical parameters. We observed foci of a serous-like pattern (low signal and no enhancement on T1-weighted, high signal on T2-weighted images) in 4 out of 28 patients (14.3%) and an intermediate signal on T1-weighted images in 4 out of 28 patients (14.3%). Serous-like lesions were located in the lower limbs and scattered in the talus, calcaneus, femurs, and humeral bones; they showed slight uptake on SPECT bone scans and were normal on CT and radiographs. Patients with serous-like lesions had significantly lower peripheral and total fat at baseline than other groups (P

2011-01-01

287

Chemical reactivity of D3h C78 (metallo)fullerene: regioselectivity changes induced by Sc3N encapsulation.  

Science.gov (United States)

We report here for the first time a full comparison of the exohedral reactivity of a given fullerene and its parent trinitride template endohedral metallofullerene. In particular, we study the thermodynamics and kinetics for the Diels-Alder [4 + 2] cycloaddition between 1,3-butadiene and free D3h'-C78 fullerene and between butadiene and the corresponding endohedral D3h-Sc3N@C78 derivative. The reaction is studied for all nonequivalent bonds, in both the free and the endohedral fullerenes, at the BP86/TZP//BP86/DZP level. The change in exohedral reactivity and regioselectivity when a metal cluster is encapsulated inside the cage is profound. Consequently, the Diels-Alder reaction over the free fullerene and the endohedral derivative leads to totally different cycloadducts. This is caused by the metal nitride situated inside the fullerene cage that reduces the reactivity of the free fullerene and favors the reaction over different bonds. PMID:18412347

Osuna, Sílvia; Swart, Marcel; Campanera, Josep M; Poblet, Josep M; Solà, Miquel

2008-04-16

288

Pathological changes after bone marrow and skin allograft transplantation in rats inflicted with severe combined radiation-burn injury  

International Nuclear Information System (INIS)

[en] Bone marrow and skin allografts from the same donor were transplanted to rats inflicted with 8 Gy ?-radiation combined with third degree burns of 15% body surface area within 6 hr post injury. Pathological changes of hematopoietic tissues and skin allografts were studied. All injured controls died within 7 days post injury without bone marrow regeneration; 50% of treated rats survived with living skin allografts on 50th day post injury. On days 100 and 480 post operation, grafted skin still survived well on recipients with normal ultrastructure. Epidermic cells of skin allografts proliferated on day 5, developed and repaired on day 10. Histological structure of the skin returned to normal on day 30 post operation. The regeneration of bone marrow appeared on 5th day, increased markedly on day 10, and almost completed on day 15 after bone marrow transplantation. However, the regeneration of lymphocytes in cortex of spleen and lymph nodes did not appear until day 15 of BMT. The results show that bone marrow and skin allograft transplantation at early time post injury in most severe combined radiation-burn injury have tremendous beneficial effects, and the skin allograft can survive for a long time

1994-01-01

289

Quantification of bone changes in a collagen-induced arthritis mouse model by reconstructed three dimensional micro-CT.  

UK PubMed Central (United Kingdom)

BACKGROUND: Inflammatory arthritis is a chronic disease, resulting in synovitis and subchondral and bone area destruction, which can severely affect a patient's quality of life. The most common form of inflammatory arthritis is rheumatoid arthritis (RA) in which many of the disease mechanisms are not well understood. The collagen-induced arthritis (CIA) mouse model is similar to RA as it exhibits joint space narrowing and bone erosion as well as involves inflammatory factors and cellular players that have been implicate in RA. Quantitative data for disease progression in RA models is difficult to obtain as serum blood markers may not always reflect disease state and physical disease indexes are subjective. Thus, it is important to develop tools to objectively assess disease progression in CIA. RESULTS: Micro-CT (Computed Tomography) is a relatively mature technology that has been used to track a variety of anatomical changes in small animals. In this study, micro-CT scans of several joints of control and CIA mice were acquired at 0, 4, 7, and 9 weeks after the immunization with collagen type II. Each micro-CT scan was analyzed by applying a segmentation algorithm to individual slices in each image set to provide 3-dimensional representations of specific bones including the humerus, femur, and tibia. From these representations, the volume and mean density of these bones were measured and compared. This analysis showed that both the volume and the density of each measured bone of the CIA mice were significantly smaller than those of the controls at week 7. CONCLUSIONS: This study demonstrates that micro-CT can be used to quantify bone changes in the CIA mouse model as an alternative to disease index assessments. In conclusion, micro-CT could be useful as a non-invasive method to monitor the efficacy of new treatments for RA tested in small animals.

Yang S; Hollister AM; Orchard EA; Chaudhery SI; Ostanin DV; Lokitz SJ; Mathis JM

2013-07-01

290

Quantification of bone changes in a collagen-induced arthritis mouse model by reconstructed three dimensional micro-CT  

Science.gov (United States)

Background Inflammatory arthritis is a chronic disease, resulting in synovitis and subchondral and bone area destruction, which can severely affect a patient’s quality of life. The most common form of inflammatory arthritis is rheumatoid arthritis (RA) in which many of the disease mechanisms are not well understood. The collagen-induced arthritis (CIA) mouse model is similar to RA as it exhibits joint space narrowing and bone erosion as well as involves inflammatory factors and cellular players that have been implicated in RA pathogenesis. Quantitative data for disease progression in RA models is difficult to obtain as serum blood markers may not always reflect disease state and physical disease indexes are subjective. Thus, it is important to develop tools to objectively assess disease progression in CIA. Results Micro-CT (Computed Tomography) is a relatively mature technology that has been used to track a variety of anatomical changes in small animals. In this study, micro-CT scans of several joints of control and CIA mice were acquired at 0, 4, 7, and 9 weeks after the immunization with collagen type II. Each micro-CT scan was analyzed by applying a segmentation algorithm to individual slices in each image set to provide 3-dimensional representations of specific bones including the humerus, femur, and tibia. From these representations, the volume and mean density of these bones were measured and compared. This analysis showed that both the volume and the density of each measured bone of the CIA mice were significantly smaller than those of the controls at week 7. Conclusions This study demonstrates that micro-CT can be used to quantify bone changes in the CIA mouse model as an alternative to disease index assessments. In conclusion, micro-CT could be useful as a non-invasive method to monitor the efficacy of new treatments for RA tested in small animals.

2013-01-01

291

Change in upper lip height and nostril sill after alveolar bone grafting in unilateral cleft lip alveolus patients.  

UK PubMed Central (United Kingdom)

INTRODUCTION: Alveolar bone grafting is known to reduce nasal asymmetry by supporting a defective alar base and a sunken nostril. However, there are no studies which include details of changes to the upper lip with appropriate measurements. The purpose of this study was to measure the change in the upper lip height and nostril sill after alveolar bone grafting, using photogrammetry. MATERIALS AND METHODS: The study included 18 unilateral cleft lip alveolus (UCLA) patients who were diagnosed with unilateral cleft lip and palate (mean age, 9.87 years). The patients underwent alveolar bone grafting with iliac bone between June 2007 and June 2008. The average follow-up period was 16.6 months. The average bone graft volume was 2.39 cm(3). We obtained photographs of the frontal, lateral and basal views using standardised photographic techniques. We defined 14 landmarks and measured the distance of 11 points (distance items) for the determination of upper lip height, upper lip projection and nostril sill elevation. We defined the proportion index as the ratio of the cleft side to non-cleft side or reference line (R). We compared the preoperative proportion index with the postoperative proportion index for each distance items. RESULTS: The height of the upper lip increased significantly in four of five distance items. The projection of the upper lip was more prominent, but it was not statistically significant. The nostril sill was significantly elevated in all four distance items. CONCLUSION: The height of the upper lip was elongated and the nostril sill was elevated after alveolar bone grafting in UCLA patients.

Kim SW; Park SO; Choi TH; Hai do T

2012-05-01

292

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

Energy Technology Data Exchange (ETDEWEB)

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 osteoporosis.

Kim, Sun Geun [Woosuk University Oriental Medical Hospital, Wanju (Korea, Republic of)

2006-09-15

293

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 osteoporosis.

2006-01-01

294

Quantitative analysis of alveolar bone change following implant placement using intraoral radiographic subtraction  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to develop a procedure for quantitative analysis using intraoral radiographs of alveolar bone after placement of dental implants and to consider the validity of the method. We evaluated the ten patients (2 males and 8 females, average age: 48.4 years-old), who were treated with dental implant operation in the site of mandibular molar region, since October of 1999 until September of 2000 in Kimura Dental Clinic (Kumamoto, Japan). We evaluated the intraoral radiographs taken pre- and post- operatively and at follow-up examination. To detect alveolar bone change on radiograph, we adopted the digital subtraction method. Although the radiographs were taken under an ordinary technique with cone indicator, we did not apply the standardized technique with fixing material customized for each patient. Therefore, we used geometric correction and density compensation before subtraction. We assessed the basic statistical values (mean, variance, kurtosis and skewness) of the region of interest (ROI) of the subtracted images. Also, we noted PPD (probing pocket depth) and BOP (bleeding on probing) at each site as indicators of clinical findings and all implanted sites were classified according to the PPD or BOP, i.e. PPD increased group ''PPD (+)'' and PPD stable group ''PPD (-)'', likewise BOP positive group ''BOP (+)'' and negative group ''BOP (-)''. We considered the statistical values of ROI in each group and compared these findings. Mean and variance values of PPD (+) were higher than those of PPD (-) and there was a significant difference in mean value (p=0.031). Similarly, mean and variance values of BOP (+) were statistically higher than those of BOP (-) (p=0.041 and p=0.0087, respectively). Concerning kurtosis and skewness, there was no difference between PPD (+) and PPD (-), or between BOP (+) and BOP (-). Using our method, the radiographs taken for follow-up examination could be assessed quantitatively. It is suggested that geometric correction and density compensation could abbreviate the standardized intraoral radiographic technique prepared for subtraction. (author)

Kimura, Hiroyuki; Kanda, Shigenobu [Kyushu Univ., Fukuoka (Japan). Graduate School of Dental Science; Tanaka, Takemasa [Kyushu Univ., Fukuoka (Japan). Dental Hospital

2002-12-01

295

Pathomorphological changes of bone marrow adipocytes in process of steroid-associated osteonecrosis  

Science.gov (United States)

Objective: The role of extravascular fat deposition in pathogenesis of steroid-associated osteonecrosis (ON) still remains unclear. This study aimed to explore the pathomorphological changes of bone marrow adipocytes over time in a rabbit ON model. Methods: Thirty-two adult rabbits were divided into control group (n=16) and steroid group (n=16). Rabbits in the steroid group were injected with venous lipopolysaccharide once and intramuscular methylprednisolone trice to induce ON. Rabbits in the control group were treated with normal saline of equal volume. 2 weeks (early stage; n=8) and 4 weeks (late stage; n=8) after the last steroid injection, animals were sacrificed, and bilateral femora were harvested. The density, diameter and area of bone marrow adipocytes were determined by histomorphometry, and ON was evaluated histopathologically. Results: The adipocyte density in steroid group increased by 67.1% and 54.4% at week 2 and week 4, respectively, when compared with control group, but there was no significant difference between week 2 and week 4. The adipocyte diameter in the steroid group at week 4 was significantly larger than that in the control group, but the adipocyte diameter in the steroid group at week 2 was slightly smaller than that in the control group. The adipocyte area in the steroid group increased by 44% and 83.4% at week 2 and week 4, respectively, when compared with the control group, and the adipocyte area in the steroid group at week 4 was markedly larger than that at week 2. In the control group, there were a largest number of adipocytes with 40-50 ?m in diameter. When compared with the control group, most of increased adipocytes in the steroid group at week 2 were 30-40 ?m in diameter, and those at week 4 were 50-60 ?m in diameter. In the steroid group, histopathological examination showed ON was found in 25% (2/8) of rabbits at week 2 and 87.5% (7/8) of rabbits at week 4. Conclusion: In the process of ON, extravascular fat deposition is characterized by increased small adipocytes at the early stage and hypertrophy of adipocytes at the late stage.

Sheng, Hui; Sheng, Chun-Jun; Cheng, Xiao-Yun; Zhang, Ge; Lee, Kwong-Man; Leung, Kwok-Sui; Qu, Shen; Qin, Ling

2013-01-01

296

Pathomorphological changes of bone marrow adipocytes in process of steroid-associated osteonecrosis.  

UK PubMed Central (United Kingdom)

OBJECTIVE: The role of extravascular fat deposition in pathogenesis of steroid-associated osteonecrosis (ON) still remains unclear. This study aimed to explore the pathomorphological changes of bone marrow adipocytes over time in a rabbit ON model. METHODS: Thirty-two adult rabbits were divided into control group (n=16) and steroid group (n=16). Rabbits in the steroid group were injected with venous lipopolysaccharide once and intramuscular methylprednisolone trice to induce ON. Rabbits in the control group were treated with normal saline of equal volume. 2 weeks (early stage; n=8) and 4 weeks (late stage; n=8) after the last steroid injection, animals were sacrificed, and bilateral femora were harvested. The density, diameter and area of bone marrow adipocytes were determined by histomorphometry, and ON was evaluated histopathologically. RESULTS: The adipocyte density in steroid group increased by 67.1% and 54.4% at week 2 and week 4, respectively, when compared with control group, but there was no significant difference between week 2 and week 4. The adipocyte diameter in the steroid group at week 4 was significantly larger than that in the control group, but the adipocyte diameter in the steroid group at week 2 was slightly smaller than that in the control group. The adipocyte area in the steroid group increased by 44% and 83.4% at week 2 and week 4, respectively, when compared with the control group, and the adipocyte area in the steroid group at week 4 was markedly larger than that at week 2. In the control group, there were a largest number of adipocytes with 40-50 ?m in diameter. When compared with the control group, most of increased adipocytes in the steroid group at week 2 were 30-40 ?m in diameter, and those at week 4 were 50-60 ?m in diameter. In the steroid group, histopathological examination showed ON was found in 25% (2/8) of rabbits at week 2 and 87.5% (7/8) of rabbits at week 4. CONCLUSION: In the process of ON, extravascular fat deposition is characterized by increased small adipocytes at the early stage and hypertrophy of adipocytes at the late stage.

Sheng H; Sheng CJ; Cheng XY; Zhang G; Lee KM; Leung KS; Qu S; Qin L

2013-01-01

297

Vitamin D Status and Bone Mineral Density Changes During Alendronate Treatment in Postmenopausal Osteoporosis.  

UK PubMed Central (United Kingdom)

Vitamin D supplementation is recommended for women with osteoporosis. In the FOCUS-D trial comparing the combination tablet alendronate plus vitamin D3 5,600 IU (ALN/D) with standard care (SC) prescribed by patients' personal physicians, ALN/D was more effective in improving serum 25(OH)D and bone turnover markers by 6 months and increasing spine and hip bone mineral density (BMD) after 1 year than SC. This post hoc analysis examined the relationship between BMD gain and 25(OH)D in women in SC receiving alendronate (SC/ALN, n = 134, 52 % of the SC group) and in the ALN/D group (n = 257). At baseline, participants were of mean age 73 years and 72 % were Caucasian, with a mean 25(OH)D of 14.9 ng/mL. In the SC/ALN group, most received vitamin D, although intake of vitamin D varied extensively (51 % received <400 ?g/day). In this group, end-of-study 25(OH)D correlated positively with mean percent increases from baseline in lumbar spine and femoral neck BMD [Pearson correlation coefficients (95 % CI) = 0.23 (0.02-0.41) and 0.24 (0.03-0.41), respectively]. Baseline 25(OH)D correlated with increases in only lumbar spine BMD [Pearson correlation coefficient (95 % CI) = 0.22 (0.01-0.40)]. No correlations between mean BMD change and 25(OH)D were seen with ALN/D. In conclusion, in postmenopausal women with osteoporosis and low 25(OH)D receiving alendronate and a wide range of vitamin D doses, the increase in lumbar spine and femoral neck BMD was positively correlated with serum 25(OH)D achieved by the end of the study and, to some extent, with 25(OH)D concentrations at baseline. The degree of success of alendronate therapy for osteoporosis may depend on the vitamin D status of patients.

Roux C; Binkley N; Boonen S; Kiel DP; Ralston SH; Regnister JY; Pong A; Rosenberg E; Santora A

2013-08-01

298

Bone turnover response to changes in calcium intake is altered in girls and adult women in families with histories of osteoporosis.  

UK PubMed Central (United Kingdom)

Heredity and environmental factors contribute to the development of osteoporosis. Because calcium is the major mineral in bone and adolescence is a key period in bone acquisition, we hypothesized that bone turnover would be less responsive to alterations in dietary calcium intake in both girls and adult women from families with histories of osteoporosis. To address this issue, we studied calcium kinetics in the maternal grandmother (age range 56-81 years), mother (age range 32-47 years), and granddaughter (age range 8-15 years) in 10 multigenerational families. In five families, the mother and/or grandmother had osteoporosis (bone mineral density > or = 2 SD below the age-specific mean). To examine both active and passive calcium absorption, families consumed low- (279 +/- 64 mg/day) and high- (1580 +/- 385) calcium diets for 10 days prior to administration of oral (46Ca) and intravenous (42Ca) stable isotopes. Using repeated measures analysis of variance, fractional calcium absorption, true calcium absorption, bone calcium deposition, and the balance in bone calcium turnover were all significantly affected by diet (p < 0.01). Females from nonosteoporotic families had decreased bone calcium resorption with little change in bone calcium deposition during the high-calcium study. In contrast, girls and adult women from osteoporotic families had increased both bone calcium deposition and resorption during the high-calcium period, leading to a less positive balance in bone calcium turnover. A significant interaction between bone status and diet was found for bone calcium resorption (p < 0.05) and approached significance for bone calcium deposition (p < 0.07), effects which were independent of generation. We conclude that girls and women from osteoporotic families have a significantly altered bone turnover response to acute changes in calcium intake.

O'Brien KO; Abrams SA; Liang LK; Ellis KJ; Gagel RF

1998-03-01

299

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

Energy Technology Data Exchange (ETDEWEB)

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

300

Time-Dependent Changes in Fresh-Frozen Bone Block Grafts: Tomographic, Histologic, and Histomorphometric Findings.  

UK PubMed Central (United Kingdom)

BACKGROUND: Bone allografts have shown satisfactory clinical results in alveolar ridge reconstructions. However, the process of incorporation and the resorption rates of these grafts are not yet fully understood. PURPOSE: The aim of this study was to use computed tomography (CT), histology, and histomorphometry to assess the time-dependent rates of resorption and incorporation of fresh-frozen bone allografts. MATERIALS AND METHODS: Twenty-four patients underwent alveolar ridge reconstruction with bone block allografts and were randomly allocated to three groups with different graft healing periods (4, 6, or 8 months) before implant placement. To assess the resorption rates, CT scans were acquired within 7 days after bone graft surgery and at the end of the period. Graft samples were collected and sent for histological and histomorphometric analyses. RESULTS: The graft resorption mean rates were 50.78%?±?10.43, 32.77%?±?7.84, and 13.02%?±?3.86 for the 4-, 6-, and 8-month groups, respectively, and were significantly different among the three groups. Newly formed bone with osteocytes near the grafted bone was observed in all three groups. The number of osteocytes was significantly lower at 4 months. Grafted bone remains were significantly higher in the shortest period of time. All of the grafts showed large amounts of calcified tissue. CONCLUSIONS: All three groups showed new bone formation and different bone resorption rates. Graft healing periods of 4 months showed less graft resorption and seemed to be the most favorable for implant placement. Healing periods of 8 months showed the largest rate of graft resorption, which could render the grafts unfavorable for implant placement.

Deluiz D; Oliveira LS; Pires FR; Tinoco EM

2013-07-01

 
 
 
 
301

An extreme change in structural and optical properties of indium oxynitride deposited by reactive gas-timing RF magnetron sputtering  

International Nuclear Information System (INIS)

[en] The indium oxynitride (InON) films were achieved by reactive RF magnetron sputtering indium target which has the purity of 99.999% with a novel reactive gas-timing technique. The structural, optical and electrical properties in a series of polycrystalline InON films affected by gas-timing of reactive N2 and O2 gases introduced to the chamber were observed. The X-ray photoelectron spectroscopy revealed that the oxygen content in thin films that compounded to indium and nitrogen, which increased from 10% in indium nitride (InN) to 66% in indium oxide (In2O3) films. The X-ray diffraction peaks show that the phase of deposited films changes from InN to InON and to In2O3 with an increasing oxygen timing. The hexagonal structure of InN films with predominant (0 0 2) and (0 0 4) orientation was observed when pure nitrogen is only used as sputtering gas, while InON and In2O3 seem to demonstrate body-center cubic polycrystalline structures depending on gas-timing. The surface morphologies investigated from atomic force microscope of deposited films with varying gas-timing of O2:N2 show indifferent. The numerical algorithm method was used to define the optical bandgap of films from transmittance results. The increasing oxygen gas-timing affects extremely to the change of crystallinity phase from InN to InON and to In2O3, the increase of optical bandgap from 1.4 to 3.4 eV and the rise of sheet resistance from 15 ?/? to insulator

1052-01-00

302

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

Science.gov (United States)

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

303

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

UK PubMed Central (United Kingdom)

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.

Sharova EV; Migalev AS; Kulikov MA; Voronov VG; Boldyreva GN; Zhavoronkova LA; Skoriatina IG; Piashina DV; Davydova NIu; Pronin IN; Kornienko VN

2012-03-01

304

An extreme change in structural and optical properties of indium oxynitride deposited by reactive gas-timing RF magnetron sputtering  

Energy Technology Data Exchange (ETDEWEB)

The indium oxynitride (InON) films were achieved by reactive RF magnetron sputtering indium target which has the purity of 99.999% with a novel reactive gas-timing technique. The structural, optical and electrical properties in a series of polycrystalline InON films affected by gas-timing of reactive N{sub 2} and O{sub 2} gases introduced to the chamber were observed. The X-ray photoelectron spectroscopy revealed that the oxygen content in thin films that compounded to indium and nitrogen, which increased from 10% in indium nitride (InN) to 66% in indium oxide (In{sub 2}O{sub 3}) films. The X-ray diffraction peaks show that the phase of deposited films changes from InN to InON and to In{sub 2}O{sub 3} with an increasing oxygen timing. The hexagonal structure of InN films with predominant (0 0 2) and (0 0 4) orientation was observed when pure nitrogen is only used as sputtering gas, while InON and In{sub 2}O{sub 3} seem to demonstrate body-center cubic polycrystalline structures depending on gas-timing. The surface morphologies investigated from atomic force microscope of deposited films with varying gas-timing of O{sub 2}:N{sub 2} show indifferent. The numerical algorithm method was used to define the optical bandgap of films from transmittance results. The increasing oxygen gas-timing affects extremely to the change of crystallinity phase from InN to InON and to In{sub 2}O{sub 3}, the increase of optical bandgap from 1.4 to 3.4 eV and the rise of sheet resistance from 15 {omega}/{open_square} to insulator.

Sungthong, A. [Nanotechnology Research Center of KMITL, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand); Department of Applied Physics, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand)], E-mail: s9067001@kmitl.ac.th; Porntheeraphat, S.; Poyai, A. [Thai Microelectronics Center, National Electronics and Computer Technology Center, Pathumthani 12120 (Thailand); Nukeaw, J. [Nanotechnology Research Center of KMITL, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand); Department of Applied Physics, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand)

2008-09-30

305

Age dependent T2 changes of bone marrow in pediatric wrist MRI  

Energy Technology Data Exchange (ETDEWEB)

Hyperintensity of the bone marrow on fluid-sensitive sequences can be seen on magnetic resonance imaging (MRI) during childhood, even in the absence of bone pathology. They can be related to hematopoietic marrow, normal and abnormal bone remodeling. We sought to investigate whether hyper intensity of the bone marrow on MRI of the wrist is age-dependent and to evaluate if this signal follows a consistent age-related pattern. Thirty-one wrist 1.5 T MR images of children (7-18 years) without suspected bone pathology were evaluated for foci of hyperintense bone marrow seen on fluid-sensitive coronal sequences using a scale of 1-3. Correlation of frequency, location and intensity of these foci with age was obtained. Results were analyzed for distribution in single bones and in the following regions: distal forearm, first/second carpal rows, and metacarpal bases. A total of 448 bones were evaluated. Eighty-eight out of 448 (21 out of 31 wrists) showed hyperintense bone marrow seen on fluid-sensitive sequences. The distribution was: radius in 19, ulna in 19, first metacarpal base in 11, scaphoid in 9, lunate in 6, pisiform in 6, and fifth metacarpal base in 1. The involvement of the first and second carpal rows and the metacarpal bases was almost similar (13, 12, and 12 respectively). In the distal forearm, the intensity was similar to or higher than that in the wrist (2.2 vs. 2.0). Frequency decreased with age (100% at 7-9 and 25% at 16-18 years). Foci of hyperintense bone marrow seen on fluid-sensitive sequences can be seen on MRI of the wrist during childhood even without apparent symptoms. It shows a consistent pattern with maturation: frequency and intensity decrease and there is distal-to-proximal resolution. This may be a normal finding that may represent normal bone remodeling or decreasing hematopoietic marrow and should not be confused with pathological bone marrow edema. (orig.)

Shabshin, Nogah [Chaim Sheba Medical Center, Department of Diagnostic Imaging, Tel-HaShomer (Israel); Schweitzer, Mark E. [The Ottawa Hospital, The University of Ottawa, Department of Diagnostic Imaging, Ottawa (Canada)

2009-12-15

306

MRI signal changes of the bone marrow in HIV-infected patients with lipodystrophy: correlation with clinical parameters  

Energy Technology Data Exchange (ETDEWEB)

To assess the prevalence, imaging appearance, and clinical significance, of bone marrow MR signal changes in a group of human immunodeficiency virus (HIV)-infected patients with lipodystrophy syndrome. Twenty-eight HIV-infected patients with lipodystrophy syndrome treated with highly active antiretroviral therapy, and 12 HIV-negative controls underwent MRI of the legs. Whole-body MRI, SPECT/CT, and a complete radiographic skeletal survey were obtained in subjects with signal changes in bone marrow. MRI and clinical evaluations were reviewed 6 months after baseline to determine changes after switching from thymidine analogs (TA) to tenofovir-DF (TDF). MRI results correlated with clinical parameters. We observed foci of a serous-like pattern (low signal and no enhancement on T1-weighted, high signal on T2-weighted images) in 4 out of 28 patients (14.3%) and an intermediate signal on T1-weighted images in 4 out of 28 patients (14.3%). Serous-like lesions were located in the lower limbs and scattered in the talus, calcaneus, femurs, and humeral bones; they showed slight uptake on SPECT bone scans and were normal on CT and radiographs. Patients with serous-like lesions had significantly lower peripheral and total fat at baseline than other groups (P < 0.05). No changes at 6 months were observed on MRI, and the serous-like lesion group showed good peripheral fat recovery after changing drug treatment. A serous-like MRI pattern is observed in the peripheral skeletons of HIV-infected patients with lipodystrophy, which correlates with peripheral lipoatrophy, and should not be misdiagnosed as malignant or infectious diseases. Although the MR lesions did not improve after switching the treatment, there was evidence of lipoatrophy recovery. (orig.)

Garcia, Ana I.; Tomas, Xavier; Pomes, Jaume; Amo, Montserrat del [Hospital Clinic, Department of Radiology, Barcelona (Spain); Milinkovic, Ana; Perez, Inaki; Mallolas, Josep [IDIBAPS-Hospital Clinic, Department of Infectious Diseases, Barcelona (Spain); Rios, Jose [Hospital Clinic, Department of Biostatistics, Barcelona (Spain); Vidal-Sicart, Sergi [Hospital Clinic, Department of Nuclear Medicine, Barcelona (Spain)

2011-10-15

307

Joint pain undergoes a transition in accordance with signal changes of bones detected by MRI in hip osteoarthritis.  

UK PubMed Central (United Kingdom)

OBJECTIVES: In this study, we aimed to investigate whether joint pain is derived from cartilage or bone alterations. METHODS: We reviewed 23 hip joints of 21 patients with primary hip osteoarthritis (OA), which were classified into Kellgren-Laurence (KL) grading I to IV. Plain radiographs and magnetic resonance imaging (MRI) were obtained from all of the 23 joints. Two of the 21 patients had bilateral hip OA. Pain was assessed based on the pain scale of Denis. A Welch t test was performed for age, height, weight, body mass index, bone mineral density, and a Mann-Whitney U test was performed for KL grading. RESULTS: Four of 8 hip joints with pain and OA showed broad signal changes detected by MRI. Fourteen hip joints without pain, but with OA did not show broad signal changes by MRI. Collectively, MRI analyses showed that broad signal changes in OA cases without joint pain or with a slight degree of joint pain were not observed, while broad signal changes were observed in OA cases with deteriorated joint pain. CONCLUSION: Our findings suggest that hip joint pain might be associated with bone signal alterations in the hips of OA patients.

Kamimura M; Nakamura Y; Ikegami S; Uchiyama S; Kato H

2013-01-01

308

Reactive nitrogen in the environment and its effect on climate change  

International Nuclear Information System (INIS)

[en] 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.

2011-01-01

309

Clonal deletion of self-reactive T cells at the early stage of T cell development in thymus of radiation bone marrow chimeras  

International Nuclear Information System (INIS)

[en] Sequential appearance of T cell subpopulations occurs in the thymocytes of irradiated C3H/He mice (H-2k, Mls-1b2a, Thy-1.2) after transplantation with bone marrow cells of AKR/J mice (H-2k, Mls-1a2b, Thy-1.1) (AKR----C3H chimeras). The donor-derived thymocytes of AKR----C3H chimeras on day 14 after bone marrow transplantation (BMT) contained a large number of blastlike CD4+CD8+ cells which represent relatively immature thymocytes, whereas those on day 21 after BMT consisted of small sized CD4+,CD8+ cells which represent a great part in normal thymocytes. To define the developmental stage at which clonal deletion of self-reactive T cells occurs in adult thymus, we followed the fate of V beta 6- or V beta 11-bearing T cells in the donor-derived thymocytes at the early stage of AKR----C3H chimeras. Mature thymocytes expressing high intensity of V beta 6 or V beta 11, which are involved in recognition of Mls-1a or MHC I-E gene products, respectively, were deleted from the donor-derived thymocytes on day 21. Immature thymocytes expressing low intensity of V beta 6 in CD3low thymocyte fraction decreased in proportion, whereas those expressing low intensity of V beta 11 rather increased in proportion in the donor-derived thymocytes of AKR----C3H chimeras from day 14 to day 21 after BMT. These results suggest that the clonal deletion of V beta 6-positive cells occurs just at the stage of immature CD3lowCD4+CD8+ cells, whereas the clonal deletion of V beta 11-positive cells may begin at the transitional stage from CD3lowCD4+CD8+ cells to CD3high single positive cells. Timing of negative selection of thymocytes may vary in distinct T cells capable of recognizing different self-Ag

1990-07-01

310

Changes of microRNA profile and microRNA-mRNA regulatory network in bones of ovariectomized mice.  

UK PubMed Central (United Kingdom)

Growing evidence shows the possibility of role of microRNAs (miRNA) in regulating bone mass. We investigated the change of miRNAs and mRNA expression profiles in bone tissue in ovariectomized mice model and evaluated regulatory mechanism of bone mass mediated by miRNAs in estrogen deficiency state. Eight-week old female C3H/HeJ mice underwent ovariectomy (OVX) or sham operation (Sham-op) and their femur and tibia were harvested to extract total bone RNAs after 4 weeks for microarray analysis. Eight miRNAs (miR-127, -133a, -133a*, -133b, -136 -206, -378, -378*) were identified to be upregulated after OVX while one miRNA (miR-204) was downregulated. Concomitant analysis of mRNA microarray revealed that 658 genes were differentially expressed between OVX and Sham-op mice. Target prediction of differentially expressed miRNAs identified potential targets and integrative analysis using the mRNA microarray results showed that PPAR? and CREB pathways are activated in skeletal tissues after ovariectomy. Among the potential candidates of miRNA, we further studied the role of miR-127 in vitro, which exhibited the greatest changes after OVX. We also studied the effects of miR-136, which has not been studied in the context of bone mass regulation. Transfection of miR-127 inhibitor has enhanced osteoblastic differentiation in UAMS-32 cells as measured by alkaline phosphatase activities and mRNA expression of osteoblast-specific genes while miR-136 precursor has inhibited osteoblastic differentiation. Furthermore, transfection of both miR-127 and miR-136 inhibitors enhanced the osteocyte-like morphological changes and survival in MLO-Y4 cells while precursors of miR-127 and -136 has aggravated dexamethasone-induced cell death. Both of the precursors enhanced osteoclastic differentiation in bone marrow macrophages, indicating that both miR-127 and -136 are negatively regulating bone mass. Taken together, these results suggest a novel insight into the association between distinct miRNAs expression and their possible role through regulatory network with mRNAs in the pathogenesis of estrogen deficiency induced osteoporosis.

An JH; Ohn JH; Song JA; Yang JY; Park H; Choi HJ; Kim SW; Kim SY; Park WY; Shin CS

2013-08-01

311

Structural changes in femoral bone tissue of rats after subchronic peroral exposure to selenium.  

UK PubMed Central (United Kingdom)

BACKGROUND: The role of selenium (Se) on bone microarchitecture is still poorly understood. The present study aims to investigate the macroscopic and microscopic structures of femoral bone tissue in adult male rats after subchronic peroral administration of Se. METHODS: Twenty one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group (Se group) young males were exposed to 5 mg Na(2)SeO(3)/L in drinking water, for 90 days. Ten one-month-old males without Se administration served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy. RESULTS: The body weight, femoral length and cortical bone thickness were significantly decreased in Se group rats. These rats also displayed different microstructure in the middle part of the femur, both in medial and lateral views, where vascular canals expanded into the central area of the bone while, in control rats, these canals occurred only near the endosteal surfaces. Additionally, a smaller number of primary and secondary osteons was identified in Se group rats. Histomorphometric analyses revealed significant increases for area, perimeter, maximum and minimum diameters of primary osteons' vascular canals but significant reductions for all measured variables of Haversian canals and secondary osteons. CONCLUSIONS: Se negatively affected the macroscopic and microscopic structures of femoral bone tissue in adult male rats. The results contribute to the knowledge on damaging impact of Se on bone.

Martiniaková M; Bobo?ová I; Omelka R; Grosskopf B; Stawarz R; Toman R

2013-01-01

312

MR tomography of bone marrow changes after high-dose chemotherapy and autologous peripheral stem cell transplantation  

International Nuclear Information System (INIS)

[en] Purpose: Evaluation of MR standard imaging and short time inversion recovery (STIR) imaging to assess changes in red bone marrow cellularity after high-dose chemotherapy (HDC) and peripheral blood stem cells transplantation (PBSCT). Results: STIR sequences demonstrated marked changes in signal intensity not only until the aplasia occurred but also during bone marrow repopulation. An increased signal intensity was observed after HDC in 13/15 patients (87%), followed by a decrease in signal intensity immediately after aplasia in 14/15 patients (93%). Signal intensity further changed parallel to marrow engraftment in 11/15 patients (73%). T2-TSE only showed clear changes during repopulation in 8/15 patients (53%). The individual course of the signal in T1-TSE was markedly inhomogeneous. Conclusions: STIR sequences show bone marrow edema during aplasia and marrow cellularity during reconstitution and are suitable for characterisation of red bone marrow after HDC and autologous PBSCT. (orig.)[de] Ziel: Evaluation von T1- und T2-gewichteten Turbo-Spin-Echo und Short-Time-Inversion-Recovery (STIR)-Sequenzen fuer die Darstellung von Knochenmarkveraenderungen nach Hochdosis-Chemotherapie (HDC) mit peripherer Blutstammzell-Transplantation (PBSZT). Ergebnisse: Die STIR-Aufnahmen zeigten die deutlichsten Signalveraenderungen im Verlauf der HDC und waehrend der Knochenmark-Rekonstitution. Initial kam es zu einem eindeutigen Signalanstieg bei 13/15 (87%) Patienten, wohl aufgrund eines Markoedems nach der HDC. Ein darauf folgender Signalabfall bei 14/15 (93%) Patienten war gefolgt von einem mit der Markzellularitaet vereinbaren Signalverlauf bei 11/15 Patienten (73%). Die T2-TSE zeigten im Verlauf der Markrepopulation nur bei 8/15 Patienten (53%) eine erkennbare Signalveraenderung. Die Signalverhaeltnisse in den T1-gewichteten Tomogrammen verliefen individuell sehr unterschiedlich. Schlussfolgerung: Die STIR-Sequenzen erfassen in der Aplasie das Knochenmarkoedem und im Verlauf der Rekonstitution die Zellularitaet des Knochenmarks und sind fuer die Charakterisierung des Knochenmarks nach HDC und PBSZT geeignet. (orig.)

1999-01-01

313

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

UK PubMed Central (United Kingdom)

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<0.001), but not by the origin of the autogenous bone graft (P=0.2). CONCLUSIONS: The volume of autogenous bone grafts from the iliac crest and the mandible is reduced significantly after maxillary sinus floor augmentation in minipigs. The graft volume is better preserved after the addition of Bio-Oss and the volumetric reduction is significantly influenced by the ratio of Bio-Oss and autogenous bone. However, further studies are needed addressing the amount of new bone formation and bone-to-implant contact before the final conclusion can be made about the optimal ratio of Bio-Oss and autogenous bone.

Jensen T; Schou S; Svendsen PA; Forman JL; Gundersen HJ; Terheyden H; Holmstrup P

2012-08-01

314

Reactive etching of a novel phase change material Si2Sb2Te3  

Science.gov (United States)

A novel phase change material, Si2Sb2Te3 has been reported to show good phase change abilities. Etching of this material is a critical step in the fabrication of phase change memory devices. In this paper, the characteristics of Si2Sb2Te3 etched in CF4/Ar atmosphere are investigated. The influence of the etching rate and surface roughness with different CF4/Ar ratio, pressure, and power are systematically studied. Furthermore, our X-ray photoelectron spectroscopy test results show that Te is the bottleneck to accelerating the etching rate.

Xia, Mengjiao; Rao, Feng; Song, Zhitang; Ren, Kun; Wu, Liangcai; Liu, Bo

315

Femoral bone density changes after total hip arthroplasty with uncemented taper-design stem: a five year follow-up study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We measured bone density (BD) changes to assess adaptive bone remodelling five years after uncemented total hip arthroplasty with taper-design femoral component using quantitative computed-tomography-assisted osteodensitometry (qCT). Nineteen consecutive patients (21 hips) with degenerative joint di...

Pitto, Rocco P.; Hayward, Annabel; Walker, Cameron; Shim, Vickie B.

316

Patterns of cortical oxygen saturation changes during CO2 reactivity testing in the vicinity of cerebral arteriovenous malformations.  

UK PubMed Central (United Kingdom)

BACKGROUND AND PURPOSE: The aim of this study was to test the hypothesis that patterns of cerebrovascular reactivity (CVR) in the vicinity of cerebral arteriovenous malformations (AVMs) before and after resection are not specific for this disease. METHODS: With a microspectrophotometer, cortical oxygen saturation (So2) was measured under steady-state conditions (Paco2, 33 mm Hg) before and after removal of 22 AVMs and in 30 control subjects before and after transsylvian amygdalohippocampectomy. Intraoperative vasoreactivity tests were performed by induced changes of end-tidal CO2 (25, 45, and 25 mm Hg) with simultaneous recording of local So2 in all patients. CVR patterns were established by linear regression analysis (P<0.05) to define parallel (positive) versus inverse (negative) behavior, and reactivity indexes were calculated to define their degree. RESULTS: Cortical oxygenation under steady-state conditions increased significantly (P<0.05) from preoperative to postoperative levels equally in both groups (preoperative AVM, 54.8+/-10.4%So2; postoperative AVM, 73.1+/-10.1%So2; preoperative control, 52.7+/-9.1%So2; postoperative control, 73.6+/-8.9%So2). The rate of inverse CVR patterns increased significantly (P<0.05) from before to after resection without showing statistically significant differences between groups. CONCLUSIONS: Local CVR patterns on presumably normal human cortex of control subjects are heterogeneous, including inverse behavior, and are similar to those of AVM patients before surgery. After surgery, cortical hyperemia is present in both groups, and a significant increase in inverse reactivity patterns interpreted as microvascular steal is noted. An AVM-specific CVR pattern could not convincingly be proved.

Schaller C; Schramm J; Haun D; Meyer B

2003-04-01

317

Fatty acid-induced changes in vascular reactivity in healthy adult rats.  

Science.gov (United States)

Dietary fatty acids (FAs) are known to modulate endothelial dysfunction, which is the first stage of atherosclerosis. However, their exact role in this initial phase is still unclear. The effects of isolated or combined (by 2) purified FAs from the main FA families were studied on the vascular response of isolated thoracic aorta in healthy rats to get a better understanding of the mechanisms of action of dietary FAs in regulating vascular endothelial function. Cumulative contraction curves to phenylephrine and relaxation curves to carbachol and then to sodium nitroprusside were obtained in the absence or presence of the FAs studied allowing endothelium-dependent and endothelium-independent ability of the smooth muscle to relax to be assessed in each experimental group. The endothelium-dependent vasodilator response to carbachol was lowered by eicosapentaenoic acid, whereas it was not altered either by docosahexaenoic acid alone or by combined eicosapentaenoic acid-docosahexaenoic acid, oleic acid, or stearic acid, and it was increased by linoleic acid (LA). A decreased phenylephrine-induced contraction was observed after incubation with arachidonic acid and with stearic acid. On the other hand, the endothelium-dependent relaxation was reduced by the addition of combined LA-arachidonic acid and LA-oleic acid. In conclusion, these data point out the differential effects of different types of FAs and of FAs alone vs combined on vascular reactivity. The complex nature of these effects could be partially linked to metabolic specificities of endothelial cells and to interactions between some FAs. PMID:16311092

Christon, Raymond; Marette, André; Badeau, Mylène; Bourgoin, Frédéric; Mélançon, Sébastien; Bachelard, Hélène

2005-12-01

318

Fatty acid-induced changes in vascular reactivity in healthy adult rats.  

UK PubMed Central (United Kingdom)

Dietary fatty acids (FAs) are known to modulate endothelial dysfunction, which is the first stage of atherosclerosis. However, their exact role in this initial phase is still unclear. The effects of isolated or combined (by 2) purified FAs from the main FA families were studied on the vascular response of isolated thoracic aorta in healthy rats to get a better understanding of the mechanisms of action of dietary FAs in regulating vascular endothelial function. Cumulative contraction curves to phenylephrine and relaxation curves to carbachol and then to sodium nitroprusside were obtained in the absence or presence of the FAs studied allowing endothelium-dependent and endothelium-independent ability of the smooth muscle to relax to be assessed in each experimental group. The endothelium-dependent vasodilator response to carbachol was lowered by eicosapentaenoic acid, whereas it was not altered either by docosahexaenoic acid alone or by combined eicosapentaenoic acid-docosahexaenoic acid, oleic acid, or stearic acid, and it was increased by linoleic acid (LA). A decreased phenylephrine-induced contraction was observed after incubation with arachidonic acid and with stearic acid. On the other hand, the endothelium-dependent relaxation was reduced by the addition of combined LA-arachidonic acid and LA-oleic acid. In conclusion, these data point out the differential effects of different types of FAs and of FAs alone vs combined on vascular reactivity. The complex nature of these effects could be partially linked to metabolic specificities of endothelial cells and to interactions between some FAs.

Christon R; Marette A; Badeau M; Bourgoin F; Mélançon S; Bachelard H

2005-12-01

319

Reactivity of hydroxyl radicals with neonicotinoid insecticides: mechanism and changes in toxicity.  

Science.gov (United States)

The reactivity of hydroxyl radicals (HO ) towards three neonicotonoid insecticides, namely imidacloprid, thiacloprid and acetamiprid was investigated. These radicals were generated by photolysis of H(2)O(2) solutions. Flash photolysis experiments were used to determine the rate constants of 5.5 x 10(10) M(-1)s(-1), 6 x 10(10) M(-1)s(-1), and 7.5 x 10(10) M(-1)s(-1), for the reactions of HO with acetamiprid, imidacloprid, and thiacloprid, respectively. Continuous irradiation experiments in the absence and presence of H(2)O(2) allowed the identification and toxicity evaluation of the primary photo- and oxidation products of the insecticides. In all cases, the less toxic 6-chloronicotinic acid was found to be the major product at higher degrees of oxidation. The results reported here indicate that the half life of the insecticides due to their reaction with HO radicals in natural aquatic reservoirs may vary between 5 h and 19 days, and therefore the hydroxyl radical-mediated oxidation may be a significant abiotic elimination route. However, elimination of the insecticide under such conditions might not improve the quality of the contaminated water, as the primary products of degradation still show considerable toxicity to Vibrio fischeri assays. PMID:19582278

Dell'arciprete, María L; Santos-Juanes, Lucas; Sanz, Antonio Arques; Vicente, Rafael; Amat, Ana M; Furlong, Jorge P; Mártire, Daniel O; Gonzalez, Mónica C

2009-05-27

320

Cr speciation changes in the presence of ozone and reactive oxygen species at low relative humidity  

Science.gov (United States)

There is limited understanding of chromium chemistry in the atmosphere as well as after particles containing chromium are captured on filters during extended sampling intervals (24 h). Thus, experiments were conducted to investigate the role of ozone (4 ppm) and particle-bound reactive oxygen species (ROS) (>700 nM of equivalent H2O2) on chromium speciation. For Cr(VI) collected on a filter, reduction to Cr(III) at 24 °C, pH 4 and 10% RH decreased from 48 ± 3% to 26 ± 3% (p < 0.001) after 2 h of exposure, compared to the absence of added ozone (control experiments). Ozone and ROS led to some oxidation of Cr(III) to Cr(VI) (up to 7% for ozone at pH 4, up to 4.5 times for ROS and ozone at pH 9) with a steady-state concentration being reached after few hours. Ozone and ROS can compensate to some extent for Cr(VI) reduction occurring on PM-laden filters. Oxidation of Cr(III) by ozone slowed as the temperature decreased, implying that Cr(VI) sampling in a cool environment might be less likely biased by the oxidation of Cr(III) by atmospheric oxidants.

Amouei Torkmahalleh, Mehdi; Lin, Lin; Holsen, Thomas M.; Rasmussen, Don H.; Hopke, Philip K.

2013-06-01

 
 
 
 
321

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

International Nuclear Information System (INIS)

[en] 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, 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

2003-09-15

322

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

Directory of Open Access Journals (Sweden)

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; Sabyasachi Sanyal; Naibedya Chattopadhyay

2010-01-01

323

The effect of internal versus external abutment connection modes on crestal bone changes around dental implants: a radiographic analysis.  

UK PubMed Central (United Kingdom)

BACKGROUND: To the best of our knowledge, the influence of external versus internal implant-abutment connections on crestal bone remodeling has not been reported. The aim of the present study is to investigate the influence of the abutment connection on peri-implant crestal bone levels (CBLs) using radiographic recordings. METHODS: Radiographic recordings from 40 single-tooth implants (20 external and 20 internal octagonal connections; one implant/patient) in 40 patients (15 males and 25 females; mean age: 54.3 years) were selected for analyses. The radiographic evaluation included the following: 1) linear bone change (LBC); 2) dimensional change (DC); and 3) angle between the implant and adjacent bone (AIB). Differences in LBC, DC, and AIB between implant placement and 1 year after loading for each system were evaluated using a paired t test. Comparison of LBC, DC, and AIB between systems at 1 year after loading was done using analysis of covariance. The significance level was set at P ?0.05. RESULTS: Radiographic CBLs (LBCs) were reduced at 1 year after loading compared to those at implant placement to reach statistical significance for the external connection (P = 0.000) but not the internal connection (P = 0.939). CBL changes were significantly greater for the external compared to the internal connection (P = 0.000). Similarly, the DC for the external connection was significantly greater compared to that for the internal connection (P = 0.004). CONCLUSION: Within the limitations of this study, the implant-abutment connection technology appears to have a significant impact on peri-implant CBLs, with the external connection paralleled by a significant reduction of CBLs.

Koo KT; Lee EJ; Kim JY; Seol YJ; Han JS; Kim TI; Lee YM; Ku Y; Wikesjö UM; Rhyu IC

2012-09-01

324

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

Energy Technology Data Exchange (ETDEWEB)

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.

Inazumi, T.; Bell, G.E.C.; Kenik, E.A.; Kiuchi, K.

1993-01-01

325

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

Energy Technology Data Exchange (ETDEWEB)

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.

Inazumi, T.; Bell, G.E.C.; Kenik, E.A.; Kiuchi, K.

1993-01-01

326

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

1993-01-01

327

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

2006-12-15

328

Magnetic resonance imaging and image analysis of post - radiation changes of bone marrow in patients with skeletal metastases.  

Science.gov (United States)

Purpose: To evaluate the post-radiation lesions of the bone marrow with magnetic resonance imaging (MRI) and image analysis in patients with bone metastases undergoing radiation therapy (RT). Methods: Thirty-five patients with bone metastases were studied from June 2008 to December 2010. All patients had osseous metastases from various primary malignancies and underwent palliative RT. MRI was performed in a Philips Gyroscan Intera 1T scanner at the beginning of RT and 12-18 days later. T1-TSE, T2-TSE and short tau inversion recovery (STIR) sequences were used. All images obtained were evaluated for early post-radiation lesions. Additionally, 1st and 2nd order textural features were extracted from these images and were introduced into a probabilistic neural network (PNN) classifier in order to create an automated classification system for those lesions. Results: Changes of signal intensity in T1-TSE, T2-TSE and STIR sequences were evaluated for the presence of edema, fatty conversion of the bone marrow or areas of hemorrhage within the limits of the irradiated area. The automated classification system showed positive results in correctly discriminating the post-radiation lesions that MRI revealed. The overall classification accuracy for discriminating between pre-radiation and post-radiation lesions was 93.2%. Furthermore, the overall classification accuracy for discriminating between post-radiation lesions was 86.67%. Conclusion: It seems that MRI can evaluate the degree of early therapy-induced bone marrow lesions observed during the first 18 days from the beginning of RT. The proposed neural network-based classification system might be used as an assisting tool for the characterization of these lesions. PMID:24065500

Romanos, O; Solomou, E; Georgiadis, P; Kardamakis, D; Siablis, D

329

Magnetic resonance imaging and image analysis of post - radiation changes of bone marrow in patients with skeletal metastases.  

UK PubMed Central (United Kingdom)

Purpose: To evaluate the post-radiation lesions of the bone marrow with magnetic resonance imaging (MRI) and image analysis in patients with bone metastases undergoing radiation therapy (RT). Methods: Thirty-five patients with bone metastases were studied from June 2008 to December 2010. All patients had osseous metastases from various primary malignancies and underwent palliative RT. MRI was performed in a Philips Gyroscan Intera 1T scanner at the beginning of RT and 12-18 days later. T1-TSE, T2-TSE and short tau inversion recovery (STIR) sequences were used. All images obtained were evaluated for early post-radiation lesions. Additionally, 1st and 2nd order textural features were extracted from these images and were introduced into a probabilistic neural network (PNN) classifier in order to create an automated classification system for those lesions. Results: Changes of signal intensity in T1-TSE, T2-TSE and STIR sequences were evaluated for the presence of edema, fatty conversion of the bone marrow or areas of hemorrhage within the limits of the irradiated area. The automated classification system showed positive results in correctly discriminating the post-radiation lesions that MRI revealed. The overall classification accuracy for discriminating between pre-radiation and post-radiation lesions was 93.2%. Furthermore, the overall classification accuracy for discriminating between post-radiation lesions was 86.67%. Conclusion: It seems that MRI can evaluate the degree of early therapy-induced bone marrow lesions observed during the first 18 days from the beginning of RT. The proposed neural network-based classification system might be used as an assisting tool for the characterization of these lesions.

Romanos O; Solomou E; Georgiadis P; Kardamakis D; Siablis D

2013-07-01

330

Micro-morphological properties of osteons reveal changes in cortical bone stability during aging, osteoporosis, and bisphosphonate treatment in women.  

UK PubMed Central (United Kingdom)

UNLABELLED: We analyzed morphological characteristics of osteons along with the geometrical indices of individual osteonal mechanical stability in young, healthy aged, untreated osteoporotic, and bisphosphonate-treated osteoporotic women. Our study revealed significant intergroup differences in osteonal morphology and osteocyte lacunae indicating different remodeling patterns with implications for fracture susceptibility. INTRODUCTION: Bone remodeling is the key process in bone structural reorganization, and its alterations lead to changes in bone mechanical strength. Since osteons reflect different bone remodeling patterns, we hypothesize that the femoral cortices of females under miscellaneous age, disease and treatment conditions will display distinct osteonal morphology and osteocyte lacunar numbers along with different mechanical properties. METHODS: The specimens used in this study were collected at autopsy from 35 female donors (young group, n?=?6, age 32?±?8 years; aged group, n?=?10, age 79?±?9 years; osteoporosis group, n?=?10, age 81?±?9 years; and bisphosphonate group, n?=?9, age 81?±?7 years). Von Kossa-modified stained femoral proximal diaphyseal sections were evaluated for osteonal morphometric parameters and osteocyte lacunar data. Geometrical indices of osteonal cross-sections were calculated to assess the mechanical stability of individual osteons, in terms of their resistance to compression, bending, and buckling. RESULTS: The morphological assessment of osteons and quantification of their osteocyte lacunae revealed significant differences between the young, aged, osteoporosis and bisphosphonate-treated groups. Calculated osteonal geometric indices provided estimates of the individual osteons' resistance to compression, bending and buckling based on their size. In particular, the osteons in the bisphosphonate-treated group presented improved osteonal geometry along with increased numbers of osteocyte lacunae that had been formerly impaired due to aging and osteoporosis. CONCLUSIONS: The data derived from osteons (as the basic structural units of the cortical bone) in different skeletal conditions can be employed to highlight structural factors contributing to the fracture susceptibility of various groups of individuals.

Bernhard A; Milovanovic P; Zimmermann EA; Hahn M; Djonic D; Krause M; Breer S; Püschel K; Djuric M; Amling M; Busse B

2013-10-01

331

Enhanced reactivity and related optical changes of Ag nanoparticles on amorphous Al2O3 supports  

International Nuclear Information System (INIS)

[en] Pairs of samples containing Ag nanoparticles (NPs) of different dimensions have been produced under the same conditions but on different substrates, namely standard glass slides and a thin layer of amorphous aluminum oxide (a-Al2O3) on-glass. Upon storage in ambient conditions (air and room temperature) the color of samples changed and a blue-shift and damping of the surface plasmon resonance was observed. The changes are weaker for the samples on-glass and tend to saturate after 12 months. In contrast, the changes for the samples on a-Al2O3 appear to be still progressing after 25 months. While x-ray photoelectron spectroscopy shows a slight sulfurization and negligible oxidation of the Ag for the on-glass samples upon 25 months aging, it shows that Ag is strongly oxidized for the on a-Al2O3 samples and sulfurization is negligible. Both optical and chemical results are consistent with the production of a shell at the expense of a reduction of the metal core dimensions, the latter being responsible for the blue-shift and related to the small (2O3 supports goes along with specific morphological changes of the Ag NPs and the observation of nitrogen. (paper)

2013-09-13

332

Molecular and macroscopic properties of PMMA bone cement: free-radical generation and temperature change versus mixing ratio.  

Science.gov (United States)

The molecular and macroscopic changes occurring during the polymerization of poly(methyl methacrylate) (PMMA) bone cement have been investigated. Electron paramagnetic resonance (EPR) spectroscopy was used to monitor free-radical generation and this was compared to temperature changes occurring in the cement for various ratios of polymer powder to liquid monomer (P/L ratio) used in the sample preparation. Both the concentration and the characteristic growth time of the free radicals associated with the polymerization of the bone cement depended on the P/L ratio used. Larger P/L ratio resulted in shorter characteristic growth time for the free radicals as well as a shorter time for the occurrence of the peak sample temperature. Smaller P/L ratios gave smaller maximum concentrations of free radicals and larger peak temperatures. These results are explained on the basis of (1) more initiators present at higher P/L ratios resulting in faster polymerization and (2) less initiators and more monomers present at smaller P/L ratios resulting in fewer radicals but more exothermic reactions. The free radicals present in the bone cement due to the manufacturer's sterilization process were found to be proportional to the fraction of powder used in the preparation, indicating negligible monomer loss during sample mixing. PMID:6292229

Turner, R C; Atkins, P E; Ackley, M A; Park, J B

1981-05-01

333

Molecular and macroscopic properties of PMMA bone cement: free-radical generation and temperature change versus mixing ratio.  

UK PubMed Central (United Kingdom)

The molecular and macroscopic changes occurring during the polymerization of poly(methyl methacrylate) (PMMA) bone cement have been investigated. Electron paramagnetic resonance (EPR) spectroscopy was used to monitor free-radical generation and this was compared to temperature changes occurring in the cement for various ratios of polymer powder to liquid monomer (P/L ratio) used in the sample preparation. Both the concentration and the characteristic growth time of the free radicals associated with the polymerization of the bone cement depended on the P/L ratio used. Larger P/L ratio resulted in shorter characteristic growth time for the free radicals as well as a shorter time for the occurrence of the peak sample temperature. Smaller P/L ratios gave smaller maximum concentrations of free radicals and larger peak temperatures. These results are explained on the basis of (1) more initiators present at higher P/L ratios resulting in faster polymerization and (2) less initiators and more monomers present at smaller P/L ratios resulting in fewer radicals but more exothermic reactions. The free radicals present in the bone cement due to the manufacturer's sterilization process were found to be proportional to the fraction of powder used in the preparation, indicating negligible monomer loss during sample mixing.

Turner RC; Atkins PE; Ackley MA; Park JB

1981-05-01

334

Changes of bone histology during maintenance hemodialysis at various levels of dialyzate Ca concentration.  

UK PubMed Central (United Kingdom)

Bone histology (iliac crest biopsies; undecalcified sections; micromorphometry) was studied by repeated biopsies in 19 patients on maintenance hemodialysis. Sampling error was assessed by taking two biopsies at one time. After an initial biopsy, patients were dialyzed either against 3.6 mEq Ca/l dialyzate or 3.9 mEq Ca/l dialyzate for 9-16 months before a second biopsy was taken. Bone histology failed to normalize irrespective of the dialyzate Ca concentration. Surface density of endosteal fibrosis diminished in a considerable proportion of the patients (9/19). Volumetric density of osteoid fell in 5 and rose in 4 of the patients.

Malluche HH; Ritz E; Lange HP; Schoeppe W

1976-10-01

335

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

Scientific Electronic Library Online (English)

Full Text Available 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, granulocytic and megakaryocytic lineages (Figure 1), besides the presence of plasmacytosis, cytoplasmic bodies, hemophagocytosis, granuloma and intracellular and extracellular leishma (more) nia 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.

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

2011-12-01

336

Changes in cerebral vascular reactivity occur early during cardiopulmonary bypass in the rat.  

UK PubMed Central (United Kingdom)

BACKGROUND: Cardiopulmonary bypass (CPB) is known to cause cerebrovascular dysfunction. The etiology of these complications is complex, but disruption of normal cerebral endothelial function as a consequence of inflammatory or hypoperfusion phenomena have been implicated. The aim of this study was to investigate the effect of CPB time on cerebrovascular reactivity and to investigate the correlation of these findings with measured inflammatory markers. METHODS: Cardiopulmonary bypass was carried out for 30 or 60 minutes on two groups of rats. Sham groups underwent the same surgical procedure without CPB. The middle cerebral artery was harvested and prepared for assessment of induced endothelial and vascular smooth muscle cell responses. Systemic inflammation was evaluated by measuring tumor necrosis factor-alpha and immunohistochemical staining for intercellular adhesion molecule-1. RESULTS: Acetylcholine caused a dose-dependent vasodilation in the control groups that was absent in animals undergoing CPB (21.3% +/- 1.3% increase in diameter at 30 minutes in the sham group compared with 5.4% +/- 1.1% in the corresponding CPB group, p < 0.001). Significantly, this was apparent after only 30 minutes of CPB. Cardiopulmonary bypass did not alter the response to sodium nitroprusside (45.3% +/- 8.6% after 30 minutes in the sham group compared with 57.8% +/- 8.0% in the corresponding CPB group, p < 0.2). Furthermore, the contractile response to serotonin remained intact in all groups (32.9 +/- 4.6 and 27.6 +/- 2.6 at 30 and 60 minutes, respectively, in the sham groups compared with 23.1 +/- 1.6 and 28.0 +/- 4.4 in the corresponding CPB groups, p < 0.2). Cardiopulmonary bypass also led to an early and marked increase in tumor necrosis factor-alpha and overexpression of intercellular adhesion molecule-1. CONCLUSIONS: Cerebrovascular impairment appears early after the onset of CPB. The specific loss of acetylcholine-induced vasodilation suggests endothelial cell dysfunction rather than impaired vascular smooth muscle response to nitric oxide. This loss of endothelium-dependent regulatory factors after CPB may enhance vasoconstriction, impair cerebrovascular function, and contribute to neurologic injury after CPB.

Modine T; Azzaoui R; Ouk T; Fayad G; Lacroix D; Warembourg H; Bordet R; Gourlay T

2006-08-01

337

Periacetabular Bone Mineral Density Changes After Resurfacing Hip Arthroplasty Versus Conventional Total Hip Arthroplasty. A Randomized Controlled DEXA Study.  

Science.gov (United States)

A randomized controlled trial was performed to evaluate acetabular bone mineral density (BMD) changes after hip resurfacing (RHA) versus an established conventional total hip arthroplasty (THA). A total of 71 patients were allocated randomly to receive either an RHA press-fit cobalt-chromium cup (n=38) or a THA with a threaded titanium cup and polyethylene-metal-inlay insert (n=33). The BMD in five separate periacetabular regions of interest (ROI) was prospectively quantified preoperative until 24months. We conclude that, in contrast to our hypothesis, periacetabular BMD was better preserved after RHA than after placement of a conventional THA. Long term follow-up studies are necessary to see whether this benefit in bone preservation sustains over longer time periods and whether it is turned into clinical benefits at future revision surgery. PMID:23219623

Smolders, José M H; Pakvis, Dean F; Hendrickx, Baudewijn W; Verdonschot, Nico; van Susante, Job L C

2012-12-06

338

Periacetabular bone mineral density changes after resurfacing hip arthroplasty versus conventional total hip arthroplasty. A randomized controlled DEXA study.  

UK PubMed Central (United Kingdom)

A randomized controlled trial was performed to evaluate acetabular bone mineral density (BMD) changes after hip resurfacing (RHA) versus an established conventional total hip arthroplasty (THA). A total of 71 patients were allocated randomly to receive either an RHA press-fit cobalt-chromium cup (n=38) or a THA with a threaded titanium cup and polyethylene-metal-inlay insert (n=33). The BMD in five separate periacetabular regions of interest (ROI) was prospectively quantified preoperative until 24 months. We conclude that, in contrast to our hypothesis, periacetabular BMD was better preserved after RHA than after placement of a conventional THA. Long term follow-up studies are necessary to see whether this benefit in bone preservation sustains over longer time periods and whether it is turned into clinical benefits at future revision surgery.

Smolders JM; Pakvis DF; Hendrickx BW; Verdonschot N; van Susante JL

2013-08-01

339

Changes in bone mineral density after orchidectomy and hormone replacement therapy in individuals with androgen insensitivity syndrome.  

UK PubMed Central (United Kingdom)

Changes in bone mineral density (BMD) after orchidectomy and after hormone replacement therapy were reported in two patients with complete androgen insensitivity syndrome (AIS). Diagnosis of AIS was made by clinical features and confirmed by the presence of 46,XY karyotype and the presence of testis component in the removed gonads. BMD at the lumbar spine and at three sites of the femur was measured by dual energy X-ray absorptiometry (DXA). The Z scores of the lumbar spine BMD before orchidectomy were -0.8 and -3.1, confirming that patients with AIS have low BMD and that androgen plays an important role in bone mineralization in 46,XY individuals. Castration reduced BMD, but treatment with daily doses of 1.25 mg of conjugated oestrogen and 10 mg of medroxyprogesterone acetate increased BMD. These results indicate that both oestrogen and androgen play an important role in balancing BMD in men.

Mizunuma H; Soda M; Okano H; Kagami I; Miyamoto S; Ohsawa M; Ibuki Y

1998-10-01

340

Seasonal change in bone, muscle and fat in professional rugby league players and its relationship to injury: a cohort study.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To examine the anthropometric characteristics of an Australian National Rugby League team and identify the relationship to type and incidence of injuries sustained during a professional season. It was hypothesised that body composition would not change discernibly across a season and that injury would be negatively related to preseason bone and muscle mass. DESIGN: A repeated measure, prospective, observational, cohort study. SETTING: Griffith University, Gold Coast, Australia. PARTICIPANTS: 37 professional male Australian National Rugby League players, 24.3 (3.8) years of age were recruited for preseason 1 testing, of whom 25 were retested preseason 2. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome measures included biometrics; body composition (bone, muscle and fat mass; dual-energy x-ray absorptiometry; XR800, Norland Medical Systems, Inc); bone geometry and strength (peripheral quantitative CT; XCT 3000, Stratec); calcaneal broadband ultrasound attenuation (BUA; QUS-2, Quidel); diet and physical activity history. Secondary outcome measures included player injuries across a single playing season. RESULTS: Lean mass decreased progressively throughout the season (pre=81.45(7.76) kg; post=79.89(6.72) kg; p?0.05), while whole body (WB) bone mineral density (BMD) increased until mid-season (pre=1.235(0.087) g/cm(2); mid=1.296(0.093) g/cm(2); p?0.001) then decreased thereafter (post=1.256(0.100); p?0.001). Start-of-season WB BMD, fat and lean mass, weight and tibial mass measured at the 38% site predicted bone injury incidence, but no other relationship was observed between body composition and injury. CONCLUSIONS: Significant anthropometric changes were observed in players across a professional rugby league season, including an overall loss of muscle and an initial increase, followed by a decrease in bone mass. Strong relationships between anthropometry and incidence of injury were not observed. Long-term tracking of large rugby league cohorts is indicated to obtain more injury data in order to examine anthropometric relationships with greater statistical power.

Georgeson EC; Weeks BK; McLellan C; Beck BR

2012-01-01

 
 
 
 
341

[Changes in stability after cryosurgical treatment of long tubular bones. An animal experiment study  

UK PubMed Central (United Kingdom)

The incidence of spontaneous fractures after cryosurgical treatment is described in the literature. The purpose of this study in the sheep model was to analyze the possibility of minimizing the potential risk of bone failure using a new miniature cryoprobe with minimal tissue traumatism and exact control of the ablation. In each of 24 sheep ablations at the right femur and left tibia were performed by drilling. The ablation at the femur was restricted to an area of 2 cm(2) of only one cortical bone, whereas at the proximal tibia the whole tibial plateau was included. The opposite side, which was treated with analog drillings without cryoablation, served as control. The ultimate bending strength of the femur and the ultimate compression strength of the tibia were examined 2, 4, and 6 months after the operation. After 2 months there was a significant difference ( p<0.05) in the ultimate compression strength between the treated and untreated tibiae, whereas the ultimate bending strength of the treated femora tended to be lower. After 4 and 6 months the side treated with cryosurgery was only marginally weaker than the untreated side. Spontaneous fractures were not observed during the whole experimental period. The good controllability of the freezing procedure and the low iatrogenic weakening of the bone using a modern miniature cryoprobe minimizes the risk of pathological postoperative fractures. After ablation of larger bone sections, the treated extremity should be partially unloaded or managed by osteosynthesis for at least 3 months.

Popken F; Niehoff A; Emrich F; Blaecker D; Bosse M; Michael J; Brüggemann GP; Eysel P

2004-02-01

342

Hematologic and bone marrow changes in dogs experimentally infected with Rangelia vitalii.  

UK PubMed Central (United Kingdom)

BACKGROUND: Rangelia vitalii is a tick-transmitted piroplasm that causes both hemolytic and hemorrhagic disease in dogs in Brazil. OBJECTIVE: The aim of this study was to evaluate the response of the bone marrow in dogs experimentally infected with R vitalii during the acute stage of the disease. METHODS: For this study, 2 groups of a total of 12 young dogs were used. Group A was composed of healthy dogs (n = 5), and group B consisted of animals infected with R vitalii (n = 7). Blood samples were collected on days 0, 10, 20, and 30 post-inoculation and stored in EDTA tubes for a full hematology profile, including a reticulocyte count. On days 10 and 20, bone marrow samples were collected, stained, and examined. RESULTS: In infected dogs anemia was identified on days 10 and 20 post-inoculation (P < .01), and on day 20 reticulocytosis was present. Infected dogs had leukopenia due to neutropenia and eosinopenia, along with lymphocytosis and monocytosis, when compared with control animals. In bone marrow, the myeloid:erythroid ratio was significantly decreased (P < .05) in infected dogs due to increased erythroid precursors. CONCLUSIONS: Dogs experimentally infected with R vitalii develop regenerative extravascular hemolytic anemia accompanied by erythroid hyperplasia in the bone marrow. During the acute phase of the disease, leukopenia due to neutropenia and eosinopenia suggests intense tissue recruitment of these cells in response to the endothelial damage caused by this parasite.

França RT; Da Silva AS; Costa MM; Paim FC; Soares JF; Labruna MB; Mazzanti CM; Lopes ST

2013-03-01

343

Scintigraphic changes of osteoarthritis: An analysis of findings during routine bone scans to evaluate the incidence in an Indian population.  

UK PubMed Central (United Kingdom)

AIMS: The reported prevalence of osteoarthritis (OA) varies according to the method that is used to detect it. X-rays are commonly used in the diagnosis of OA. However, marked osteoarthritic damage must be present to detect characteristic changes with radiologic imaging. Our intention was to evaluate bone scans (1) he occurrence of such changes, (2) he incidence of OA (single or multiple joints) in the general population (a mixture of urban and rural) who were asymptomatic. Data on OA incidence in India is sketchy and sparse as against more detailed information obtained from USA and European nations. Also, clinical rheumatologists are not well-versed with the potential application of bone scans in the management of arthritides. MATERIALS AND METHODS: Two hundred and eighty nine planar images of routine bone scans were randomly evaluated by two trained nuclear medicine physicians. The ages of the patients ranged from 20 to over 80 years. RESULTS: It is observed that as the age increases, the incidence of joint involvement increases. However, it is worth noting that even in the age group of 20-40 years, as many as 34% of asymptomatic persons have involvement of the joints. In this age group, as the manifestation is probably in the inception stage, there is a tendency for single joint involvement as against multiple joints seen in the older age groups. Another point to note is that the incidence of joint involvement was not affected by weight. In our patient population, gross obesity was not seen. The predominant joints involved are the knees and hips, followed by the shoulders and ankles. Females show a higher incidence than males. Some patients would be having only a single site or multiple site involvement. This observation is important as in a single, simple test whole body survey gives more information with low radiation burden. CONCLUSION: Scintigraphic prevalence of OA is higher than reported in US, Europe, and Asia as this test is more sensitive in detecting early changes as compared to radiological changes. These findings on scintigraphy in asymptomatic cases have not been described to the best of our knowledge. Epidemiological demography in published reports is based on clinical or radiological changes observed in single joints which are predominantly symptomatic and multiple joint involvement is rarely recorded. The sensitivity of scintigraphy to show early changes in bone homeostasis and remodeling needs to be exploited.

Samuel AM; Jain H

2012-04-01

344

An RNA-seq protocol to identify mRNA expression changes in mouse diaphyseal bone: Applications in mice with bone property altering Lrp5 mutations.  

UK PubMed Central (United Kingdom)

Loss-of-function and certain missense mutations in the Wnt coreceptor low-density lipoprotein receptor-related protein 5 (LRP5) significantly decrease or increase bone mass, respectively. These human skeletal phenotypes have been recapitulated in mice harboring Lrp5 knockout and knock-in mutations. We hypothesized that measuring mRNA expression in diaphyseal bone from mice with Lrp5 wild-type (Lrp5(+/+) ), knockout (Lrp5(-/-) ), and high bone mass (HBM)-causing (Lrp5(p.A214V/+) ) knock-in alleles could identify genes and pathways that regulate or are regulated by LRP5 activity. We performed RNA-seq on pairs of tibial diaphyseal bones from four 16-week-old mice with each of the aforementioned genotypes. We then evaluated different methods for controlling for contaminating nonskeletal tissue (ie, blood, bone marrow, and skeletal muscle) in our data. These methods included predigestion of diaphyseal bone with collagenase and separate transcriptional profiling of blood, skeletal muscle, and bone marrow. We found that collagenase digestion reduced contamination, but also altered gene expression in the remaining cells. In contrast, in silico filtering of the diaphyseal bone RNA-seq data for highly expressed blood, skeletal muscle, and bone marrow transcripts significantly increased the correlation between RNA-seq data from an animal's right and left tibias and from animals with the same Lrp5 genotype. We conclude that reliable and reproducible RNA-seq data can be obtained from mouse diaphyseal bone and that lack of LRP5 has a more pronounced effect on gene expression than the HBM-causing LRP5 missense mutation. We identified 84 differentially expressed protein-coding transcripts between LRP5 "sufficient" (ie, Lrp5(+/+) and Lrp5(p.A214V/+) ) and "insufficient" (Lrp5(-/-) ) diaphyseal bone, and far fewer differentially expressed genes between Lrp5(p.A214V/+) and Lrp5(+/+) diaphyseal bone. © 2013 American Society for Bone and Mineral Research.

Ayturk UM; Jacobsen CM; Christodoulou DC; Gorham J; Seidman JG; Seidman CE; Robling AG; Warman ML

2013-10-01

345

[Reactive changes of the rat brain cellular elements under different conditions of circulatory hypoxia].  

UK PubMed Central (United Kingdom)

The aim of this study was to detect structural, spatial and quantitative changes of cellular elements of midbrain paranigral nucleus (PNN) and telencephalic anterior cingulate area (ACA) under different conditions of circulatory hypoxia. PNN anteriormedial part and ACA layers V-VI were examined in adult rats 7 days (n=4) after an occlusion of both common carotid arteries as well as in intact (1st control, n=4) and sham-operated animals (2nd control, n=4). In histological the sections, stained with Nissl cresyl violet, and using the methods of glial fibrillary acidic protein and an Ibal-protein detection, the proportions of unmodified, hypochromic, pyknomorphic neurons and ghost cells were determined as well as the numbers of astrocytes, oligodendrocytes, microgliocytes and endotheliocytes. Cell body area of neurons and gliocytes, and the distance between cell bodies and capillaries were measured, a gliocyte-neuronal index was calculated. It was found that brain cellular elements that survive different conditions of a circulatory hypoxia underwent a range of pathological changes. Neurons were in process of nuclear pyknosis, lysis and transformation into the ghost cells. The cells within the hypoxia nuclear zone were prone to death or pyknosis. The neurons located outside the area of hypoxia which were affected only by a humoral impact of reactions of the glutamate-calcium cascade, frequently underwent acute swelling. Microgliocyte reaction in the form of poorly expressed increase in their number and structural signs of activation was an early diffuse manifestation of a prosencephalic focal hypoxia. Endotheliocyte proliferation 7 days after of ischemic challenge was not associated with a chain of cascade reactions and was observed only in the hypoxia focus. Concentration of viable neurons and astrocytes near blood capillaries, as well as an increase in the number of satellite form gliocytes is an adaptation mechanism and a condition for the survival of cells during various types of brain exposure to ischemia.

2013-01-01

346

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

UK PubMed Central (United Kingdom)

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-energy 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%/year, p?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.

Schwartz AV; Ewing SK; Porzig AM; McCulloch CE; Resnick HE; Hillier TA; Ensrud KE; Black DM; Nevitt MC; Cummings SR; Sellmeyer DE

2013-01-01

347

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

International Nuclear Information System (INIS)

[en] 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)

2005-01-01

348

Localized sclerotic bone response demonstrated reduced nanomechanical creep properties.  

UK PubMed Central (United Kingdom)

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).

Chen X; Goh JC; Teoh SH; De SD; Soong R; Lee T

2013-01-01

349

Changing chirality during single-walled carbon nanotube growth: a reactive molecular dynamics/Monte Carlo study.  

UK PubMed Central (United Kingdom)

The growth mechanism and chirality formation of a single-walled carbon nanotube (SWNT) on a surface-bound nickel nanocluster are investigated by hybrid reactive molecular dynamics/force-biased Monte Carlo simulations. The validity of the interatomic potential used, the so-called ReaxFF potential, for simulating catalytic SWNT growth is demonstrated. The SWNT growth process was found to be in agreement with previous studies and observed to proceed through a number of distinct steps, viz., the dissolution of carbon in the metallic particle, the surface segregation of carbon with the formation of aggregated carbon clusters on the surface, the formation of graphitic islands that grow into SWNT caps, and finally continued growth of the SWNT. Moreover, it is clearly illustrated in the present study that during the growth process, the carbon network is continuously restructured by a metal-mediated process, thereby healing many topological defects. It is also found that a cap can nucleate and disappear again, which was not observed in previous simulations. Encapsulation of the nanoparticle is observed to be prevented by the carbon network migrating as a whole over the cluster surface. Finally, for the first time, the chirality of the growing SWNT cap is observed to change from (11,0) over (9,3) to (7,7). It is demonstrated that this change in chirality is due to the metal-mediated restructuring process.

Neyts EC; van Duin AC; Bogaerts A

2011-11-01

350

Changing chirality during single-walled carbon nanotube growth: a reactive molecular dynamics/Monte Carlo study.  

Science.gov (United States)

The growth mechanism and chirality formation of a single-walled carbon nanotube (SWNT) on a surface-bound nickel nanocluster are investigated by hybrid reactive molecular dynamics/force-biased Monte Carlo simulations. The validity of the interatomic potential used, the so-called ReaxFF potential, for simulating catalytic SWNT growth is demonstrated. The SWNT growth process was found to be in agreement with previous studies and observed to proceed through a number of distinct steps, viz., the dissolution of carbon in the metallic particle, the surface segregation of carbon with the formation of aggregated carbon clusters on the surface, the formation of graphitic islands that grow into SWNT caps, and finally continued growth of the SWNT. Moreover, it is clearly illustrated in the present study that during the growth process, the carbon network is continuously restructured by a metal-mediated process, thereby healing many topological defects. It is also found that a cap can nucleate and disappear again, which was not observed in previous simulations. Encapsulation of the nanoparticle is observed to be prevented by the carbon network migrating as a whole over the cluster surface. Finally, for the first time, the chirality of the growing SWNT cap is observed to change from (11,0) over (9,3) to (7,7). It is demonstrated that this change in chirality is due to the metal-mediated restructuring process. PMID:21923157

Neyts, Erik C; van Duin, Adri C T; Bogaerts, Annemie

2011-10-06

351

[Interdependent changes of the axon and Schwann cell in the process of reactive remodeling of a myelinated nerve fiber].  

UK PubMed Central (United Kingdom)

Using the inverted phase-contrast microscope, the living undamaged frog sciatic nerve fibers and the fibers mechanically injured to varying degrees, were studied. It was found that the swelling of myelin incisures (MI) (of Schmidt-Lanterman) occured according to the principles similar to those controlling the changes of the myelin gap (node of Ranvier) and depended on the swelling of a Schwann cell (SC) perikaryon. It was detected that this was a single process, which which could be united in a complex of nonspecific changes of a myelinated nerve fiber. It was also demonstrated that under the action of mechani