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  • Articles  (34)
  • Bone  (34)
  • Springer  (34)
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  • Articles  (34)
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  • Springer  (34)
  • American Chemical Society
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  • 1990-1994  (14)
  • 1980-1984  (20)
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  • 1
    Electronic Resource
    Electronic Resource
    A new semiautomatic method for quantitative static and dynamic bone histology (1982)
    Springer
    Calcified tissue international 34 (1982), S. 439-448 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Histomorphometry ; Osteocytes ; Bone dynamics ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A new semiautomatic technique combining advantages of the manual and fully automatic methods is described for obtaining quantitative static and dynamic histologic data of bone. The hardware consists of a photomicroscope, digitizing platen, digitizer, plotter/printer, floppy disc drive, and computer. The microscope is equipped with a drawing tube through which the image of the digitizing platen is projected over the optical field. The investigator selects and traces all histologic structures to be measured by moving a cursor on the digitizing platen which is visible by its projection over the histologic field. The results on accuracy and static and dynamic precision of this method show that static and dynamic parameters of bone are obtained with a degree of error (〈20%) well within the acceptable range for biologic measurements. Comparison of this method with the grid technique according to Merz and Schenck showed that for almost all micromorphometric parameters comparable absolute data are obtained. Due to the higher precision of our method, however, the number of optical fields evaluated in obtaining these comparable data could be reduced to 25% of the number of fields evaluated by the Merz and Schenck technique. The time requirements for quantitative evaluation of a histologic slide of bone by our technique are 40–50 min; 20–25 min is needed for quantitative evaluation of osteocytes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411282
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  • 2
    Electronic Resource
    Electronic Resource
    Quantitative bone histology in 84 normal American subjects (1982)
    Springer
    Calcified tissue international 34 (1982), S. 449-455 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Histomorphometry ; Normal values ; Bone biopsies ; Sampling error
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Quantitative bone histology was done in undecalcified sections of iliac crest bone specimens obtained from 84 normal American individuals. Samples were obtained within 12 h after death in a vertical and horizontal manner from both the right and left iliac crests. In addition to the determination of normal values of micromorphometric parameters of bone in these healthy American subjects, the following studies were carried out: (a) comparison of variance of micromorphometric parameters of bone obtained from the right versus left iliac bone (40 pairs), (b) comparison of micromorphometric parameters of bone obtained in a vertical versus horizontal manner (12 pairs), (c) evaluation of variance with increasing distance from the compact zone in bone samples obtained in a vertical manner (44 pairs), (d) analysis of variation between bone samples obtained more anteriorly versus posteriorly along the iliac crest (N=40), (e) comparison of differences in micromorphometric parameters obtained from age-matched men versus premenopausal women (N=12), and (f) plotting of histograms for assessment of distribution of micromorphometric parameters. The results show that histomorphometric data of bone cannot be easily compared when different techniques are employed for obtaining bone samples. Sampling variations are kept smaller when bone specimens are obtained in a vertical manner. Anterior/posterior variation does not cause major sampling error. If ranges of variation are taken into account, quantitative bone histology is a valuable tool for assessment of bone structure and bone cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411283
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  • 3
    Electronic Resource
    Electronic Resource
    Growth hormone involvement in the regulation of tartrate-resistant acid phosphatase-positive cells that are active in cartilage and bone resorption (1993)
    Springer
    Calcified tissue international 52 (1993), S. 216-221 
    Details
    ISSN: 1432-0827
    Keywords: Growth hormone ; Resorption ; Bone ; Cartilage ; Tartrate-resistant acid phosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Young male Sprague-Dawley rats (5–7 weeks old, 80–120 g) were hypophysectomized (HX) and maintained on thyroxin and dexamethasone replacement therapies. Ten days after surgery, some HX rats received a single injection of human growth hormone (hGH), and others five daily injections of hGH. Tartrate-resistant acid phosphatase (TRAP) histochemistry was employed in order to evaluate the number of cells of resorptive potential in the metaphyseal bone of the proximal tibiae of HX rats and was compared with normal rats and HX rats that further received hGH replacement therapy. In normal rats, two populations of TRAP-positive cells were identified: multinuclear cells, which showed histological characteristics of osteoclasts, and small mononuclear cells, the number of which was overwhelming when compared with the number of TRAP-positive multinuclear cells. Both populations were reduced in the HX rat, but more so the mononuclear cells, which were assumed to represent the precursor pool of mature osteoclasts and chondroclasts (P〈0.005). Five daily injections of hGH to HX rats brought about a significant increase in the number of TRAP-positive multinuclear cells, the number of nuclei of these cells, and the number of mononuclear TRAP-positive cells, throughout the metaphyseal bone (P〈0.05). A single injection of hGH increased only the number of TRAP-positive multinuclear cells in the trabecula/bone marrow interface (P〈0.05), indicating a very rapid fusion of precursor cells into mature osteoclasts in that particular location. It was concluded that GH depletion caused a major reduction in the number of cells presenting resorption capacity and that a short hGH replacement regimen resulted in a gradual restoration of these cells n the metaphyseal bone of the proximal tibia of the HX rat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00298722
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  • 4
    Electronic Resource
    Electronic Resource
    Vitamin K-induced changes in markers for osteoblast activity and urinary calcium loss (1993)
    Springer
    Calcified tissue international 53 (1993), S. 81-85 
    Details
    ISSN: 1432-0827
    Keywords: Vitamin K ; Osteocalcin ; γ-carboxyglutamic acid ; Bone ; Calcium excretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The objective of this study was to identify subjects in whom vitamin K has an effect on markers for calcium and bone metabolism and to detect hitherto-unnoticed correlations between vitamin K-induced changes in these markers. Participants in our studies were apparently healthy women, in whom we measured serum-immunoreactive osteocalcin (irOC) before and after adsorption to hydroxylapatite; total serum alkaline phosphatase (T-AP) and bonespecific alkaline phosphatase (B-AP); and fasting urinary calcium and creatinine. We describe a trial among 145 women who were treated with vitamin K (1 mg/day) for 2 weeks, and a prospective placebo-controlled trial among two groups each of 70 postmenopausal women with a treatment period of 3 months. It turned out that in elderly women vitamin K induced increased levels of serum irOC with a high affinity for hydroxylapatite (irOCbound), whereas that with low affinity (irOCfree) remained unaffected. In placebo-treated women the ratio irOCfree/irOCbound shifted from 0.38 to 0.65 around the 50th year of age. This shift was not found in vitamin K-treated women. After 3 months of treatment the vitamin K-induced changes in irOCbound were correlated with changes in B-AP, whereas irOCfree was correlated to urinary calcium excretion. In fast losers of urinary calcium vitamin K induced a 30% decrease of calcium excretion. The hypothesis is put forward that irOCbound may be a marker for bone formation, that serum irOCfree may be a marker for bone resorption, and that the serum irOCfree/irOCbound ratio may become a marker for skeletal remodeling. It is concluded that vitamin K administration may help to reduce urinary calcium loss in postmenopausal women, notably in the fast losers of calcium. The ratio irOCfree/irOCbound provides more information than total irOC and may become a practical marker for bone metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01321883
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  • 5
    Electronic Resource
    Electronic Resource
    Mechanical properties, bone mineral content, and bone composition (collagen, osteocalcin, IGF-I) of the rat femur: Influence of ovariectomy and nandrolone decanoate (anabolic steroid) treatment (1993)
    Springer
    Calcified tissue international 53 (1993), S. 269-277 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Nandrolone decanoate ; Ovariectomy ; Bone mechanics ; IGF-I ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Nandrolone decanoate (ND) is an anabolic steroid with a positive effect on bone mass in osteoporotic patients. The mechanism of action, (i.e., reduction of bone resorption and/or Stimulation of bone formation), the ultimate effect on mechanical properties, and the most effective dosage are not yet clear. To address these issues, dose-related effects of the long-term effect of ND on Serum and bone biochemistry, bone mineral content, and bone mechanical properties in ovariectomized (OVX) rats (12 weeks old at the Start of the experiment) were Studied for 6 months. The results were compared with those obtained in agematched, intact, and OVX rats. OVX caused in the femur a significant increase in net periosteal bone formation and net endosteal bone resorption of bone collagen content and torsional strength, and of Serum alkaline phosphatase, osteocalcin, and insulin-like growth factor-I (IGF-I) levels, whereas cortical bone density and calcium/creatinine and phosphorus/creatinine in 24-hour urine were Significantly reduced. Treatment of OVX rats with 1 mg ND/14 days resulted in a Significant increase in periosteal bone formation, femur length, cortical and trabecular bone mineral content and density, torsion stiffness and Strength, and bone IGF-I content, and a decrease in Serum osteocalcin, urinary calcium/creatinine levels, and bone collagen content compared with OVX controls. The higher ND dosage of 2.5 mg/14 days did not improve the results. ND treatment did not reverse all changes induced by OVX to the level of the intact controls. These results indicate that ND acts as an antiresorptive drug and as a bone formation Stimulating drug. Furthermore, the increased bone mass and bone mineral density is associated with improved bone Strength and stiffness and the presence of an increased amount of IGF-I. IGF-I is a growth factor considered to play a role in the maintenance of normal skeletal balance by a paracrine or autocrine mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01320913
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  • 6
    Electronic Resource
    Electronic Resource
    Iron distribution in thalassemic bone by energy-loss spectroscopy and electron spectroscopic imaging (1993)
    Springer
    Calcified tissue international 53 (1993), S. 29-37 
    Details
    ISSN: 1432-0827
    Keywords: Iron ; Bone ; Osteoblasts ; Ferritin ; Electron energy loss spectroscopy ; Electron spectroscopic imaging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Iron overload occurs frequently in thalassemia as a consequence of regular blood transfusions, and iron has been found to accumulate in bone, but skeletal toxicity of iron is not clearly established. In this study, bone biopsies of thalassemic patients were investigated by light (n = 6) and electron microscopy (n = 8) in order to analyze iron distribution and possible iron-associated cellular lesions. Sections (5 μm thick) were used for histomorphometry and iron histochemistry. Ultrathin sections were examined with an energy filtering transmission electron microscope. Iron was identified by electron energy loss spectroscopy (EELS), and iron distribution was visualized by electron spectroscopic imaging (ESI) associated with computer-assisted treatment (two-window method). This study shows that EELS allows the detection of 4500–9000 iron atoms, and that computer-assisted image processing is essential to eliminate background and to obtain the net distribution of an element by ESI. This study shows also that stainable iron was present along trabecular surfaces, mineralizing surfaces, and on cement lines in the biopsies of all patients. Moreover, iron was detected by EELS in small granules (diffusely distributed or condensed in large clusters), in osteoid tissue, and in the cytoplasm of bone cells, but not in the mineralized matrix. The shape and size (9–13 nm) of these granules were similar to those reported for ferritin. As for iron toxicity, all patients had osteoid volume and thickness and osteoblast surface in the normal range. Stainable iron surfaces did not correlate with osteoblast surfaces, plasma ferritin concentrations, or the duration of transfusion therapy. Numerous osteoblasts contained damaged mitochondria, and impaired osteoblast activity can therefore not be excluded.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01352012
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  • 7
    Electronic Resource
    Electronic Resource
    Skeletal demineralization in Turner's syndrome (1982)
    Springer
    Calcified tissue international 34 (1982), S. 519-522 
    Details
    ISSN: 1432-0827
    Keywords: Turner's syndrome ; Ovarian dysgenesis ; Osteoporosis ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The bone mineral status of 17 girls with Turner's syndrome was evaluated by single photon absorptiometry. Bone mineral content (BMC) was 25.4% below that predicted by normalization for age, sex, height, weight, and bone width. Only 25% of this demineralization could be attributed to delayed skeletal maturation. Bones of girls who received estrogen replacement therapy were less demineralized than those of the others. The bone mineral deficit became less pronounced with advancing age. It could not be determined if the apparent effect of estrogens was related to age or if the apparent improvement with age was really due to an effect of estrogen treatment. For 8 subjects followed longitudinally there was no significant change in the BMC deficit.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411296
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  • 8
    Electronic Resource
    Electronic Resource
    Distribution of fluoride in cortical bone of human rib (1993)
    Springer
    Calcified tissue international 52 (1993), S. 278-282 
    Details
    ISSN: 1432-0827
    Keywords: Fluoride ; Bone ; Human ; Aging ; Sex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary We describe a detailed study of fluoride distribution with age in the human cortical rib bone. Human ribs were obtained from 110 subjects (M:68,F;42) aged 20–93 years. The fluoride distribution from the periosteal to endosteal surfaces of the ribs was determined by sampling each specimen using an abrasive micro-sampling technique, and the samples were analyzed using the fluoride electrode, as described by Weatherell et al. [1]. The concentration of fluoride was highest in the periosteal region, decreased gradually towards the interior of the tissue where the concentration of fluoride tended toward the plateau, and then rose again towards the endosteal surface. Patterns of fluoride distribution changed with age, and the difference between periosteal and endosteal fluoride levels increased with age. Although average fluoride concentrations increased with age in both sexes, there was a significant difference between males and females at the age of about 55 years (P〈0.05).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00296652
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  • 9
    Electronic Resource
    Electronic Resource
    Effect of omeprazole, an inhibitor of H+, K+-ATPase, on bone resorption in humans (1993)
    Springer
    Calcified tissue international 53 (1993), S. 21-25 
    Details
    ISSN: 1432-0827
    Keywords: Omeprazole ; Bone ; Resorption ; Inhibition ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Omeprazole is an inhibitor of gastric H+, K+-ATPase. Although the major proton transport of osteoclast is mediated by a vacuolar-type H+-ATPase which is different from the gastric H+, K+-ATPase,in vitro studies have demonstrated that omeprazole inhibits bone resorption. In this study, the effect of omeprazole on bone resorption was evaluated in patients who had a history of gastric ulcer and were treated with maintenance doses of H2 blocker without any gastric complaints at the study time. H2 blocker administration was changed to omeprazole treatment in the study group and to no treatment in the control group. Urinary excretion of hydroxyproline and calcium decreased after omeprazole treatment in the study group. Serum intact PTH, alkaline phosphatase, osteocalcin, and tartrate-resistant acid phosphatase (TRAP) increased in this group. In the control group, there were not any changes in these parameters. The discrepancy between serum TRAP and urinary excretion of hydroxyproline and calcium in the study group was thought to be due to the suppression of bone resorption by omeprazole, which probably interfered the acidification at resorption lacunae and resulted in the inactivation of TRAP and other lysosomal enzymes. The results of our study suggest the possibility that the specific inhibitors of the osteoclastic proton pump (such as bafilomycins) will more effectively suppress bone resorption and be useful for the treatment of metabolic bone diseases with increased bone resorption.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01352010
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  • 10
    Electronic Resource
    Electronic Resource
    Plasma proteins in human cortical bone: Enrichment ofα 2 HS-glycoprotein,α 1 acid-glycoprotein, and IgE (1982)
    Springer
    Calcified tissue international 34 (1982), S. 229-231 
    Details
    ISSN: 1432-0827
    Keywords: Plasma proteins ; IgE ; IgD ; α 1Acid-glycoprotein ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Human cortical bones were extracted with EDTA, and the residue after EDTA extraction was digested with bacterial collagenase. Ten plasma proteins were identified and quantitated in the EDTA extracts. Three of them—IgE, IgD, andα 1acid-glycoprotein—had not previously been described in bone or dentine. Five plasma proteins identified in collagenase digests are albumin, IgG, IgA, IgE, andα 1acid-glycoprotein. IgE,α 1acid-glycoprotein, andα 2HS-glycoprotein were found to be concentrated in the bone more than other plasma proteins by factors between 11 and 525. The identification of plasma proteins was facilitated by the addition of polyethylene glycol in agarose gel. The presence of plasma proteins both in EDTA extracts and in collagenase digests suggests their structural role in bone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411242
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  • 11
    Electronic Resource
    Electronic Resource
    Effect of 1,25-dihydroxyvitamin D3 on osteopenia induced by prednisolone in adult rats (1982)
    Springer
    Calcified tissue international 34 (1982), S. 253-257 
    Details
    ISSN: 1432-0827
    Keywords: Prednisolone ; Calcium ; Bone ; Corticoid osteopenia ; Vitamin D metabolites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Adult male rats were fed a diet containing 0.15% calcium, 0.3% phosphorus, and either 100, 50, or 20 mg of prednisolone per kg of diet. All these levels of prednisolone led to osteopenia, decreased intestinal absorption of calcium, slightly lower serum calcium and phosphorus, and a decreased level of serum 1,25-dihydroxyvitamin D3. Exogenous parenteral 1,25-dihydroxyvitamin D3 corrected steroid-induced changes in serum calcium and phosphorus, but could not completely correct the low intestinal calcium transport; nor did it prevent the development of osteopenia. The prednisolone-induced osteopenia seems at least in part to be caused by impaired intestinal calcium transport. The impaired calcium transport may be the result of low levels of 1,25-dihydroxyvitamin D3 and a direct effect of presnisolone on the intestine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411246
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  • 12
    Electronic Resource
    Electronic Resource
    Role of vitamin D in maternal skeletal changes during pregnancy and lactation: A histomorphometric study (1982)
    Springer
    Calcified tissue international 34 (1982), S. 245-252 
    Details
    ISSN: 1432-0827
    Keywords: Vitamin D ; Vitamin D deficiency ; Bone ; Pregnancy ; Lactation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The effect of vitamin D on bone changes during the reproductive cycle in female rats has been investigated. One group of female rats was maintained on a vitamin D-deficient diet and another group on a vitamin D-replete diet from weaning. Both groups were mated with normal males and changes in their bones were determined histomorphometrically during pregnancy, lactation, and after weaning. All vitamin D-deficient rats had bone changes typical of rickets. Pregnancy caused significant reductions in mineralized tissue of trabecular and cortical bone in the vitamin D-deficient rats. Lactation caused further significant reductions in mineralized tissues of cortical and trabecular bone in both the vitamin D-deficient and vitamin D-replete animals, with the greatest changes seen at weaning. Some restoration of mineralized tissues occurred following weaning. There was an increase in tetracycline-labeled bone surface in the vitamin D-replete animals during lactation, likely due to an increase in bone formation rates. In the vitamin D-deficient animals during lactation, there was a decrease in tetracyclinelabeled bone surface, likely due to severely depressed bone mineralization. These results indicate that the mobilization of calcium from bone to maintain pregnancy and lactation occurs by a mechanism independent of vitamin D.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411245
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  • 13
    Electronic Resource
    Electronic Resource
    Osteogenesis in osteopetrotic mice (1982)
    Springer
    Calcified tissue international 34 (1982), S. 37-42 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Osteopetrosis ; Osteoclast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Ectopic bone arising in grafts of compatible normal intact bone marrow in microphthalmic osteopetrotic recipients was examined in the light microscope and was found to be unaffected by the deficiency that curtails resorption of primitive woven bone in osteopetrotic animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411206
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  • 14
    Electronic Resource
    Electronic Resource
    Effects of vitamin D metabolites and analogs on bone collagen synthesis in vitro (1982)
    Springer
    Calcified tissue international 34 (1982), S. 103-110 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Collagen ; Vitamin D metabolites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The effects of selected vitamin D3 metabolites and analogs on bone collagen synthesis in vitro were examined in organ cultures of neonatal mouse calvarial bone. The incorporation of [3H]proline into the collagenase-digestible fraction of newly synthesized protein was progressively inhibited by 1α,25-dihydroxyvitamin D3 (1α,25-(OH)2D3) (10−12 M to 10−7 M) in 24-h cultures, and incorporation into noncollagen protein was also blunted at the higher doses employed. The synthetic analog 1α-hydroxyvitamin D3 (1α-OHD3) was almost 300-fold less potent an inhibitor of collagen synthesis than was 1α,25(OH)2D3, and the natural metabolites 25-hydroxyvitamin D3 (25OHD3) and 24R,25-dihydroxyvitamin D3 (24R,25(OH)2D3), 1000-fold less potent, although the dose-response curve for each of these compounds was not parallel with that for 1α,25(OH)2D3. The 24S,25(OH)2D3 enantiomer was four-fold less potent than 24R,25-(OH)2D3 or 25OHD3, and vitamin D3 showed less than 2% the activity of 25OHD3. The responses were unaffected by the substitution of 0.4% bovine albumin for 5% horse serum in the medium, and no stimulation of collagen synthesis was observed in response to 25-hydroxylated metabolites between 2×10−14 and 2×10−6 M or in cultures treated for up to 96 h with 24R,25(OH)2D3 (2×10−10M). The overall results emphasize the similarity of the structural requirements for the inhibition of matrix synthesis and the stimulation of resorption by active vitamin D metabolites in bone. In addition, these studies support the importance of the 1-hydroxyl function to the biologic activity of vitamin D in the skeleton.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411216
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  • 15
    Electronic Resource
    Electronic Resource
    Serum 1,25-dihydroxyvitamin D levels in subjects with X-linked hypophosphatemic rickets and osteomalacia (1982)
    Springer
    Calcified tissue international 34 (1982), S. 125-130 
    Details
    ISSN: 1432-0827
    Keywords: X-Linked hypophosphatemic rickets ; Osteomalacia ; 1,25-Dihydroxyvitamin D ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary In order to determine whether a defect in vitamin D metabolism might play a role in the pathogenesis of X-linked hypophosphatemic rickets and osteomalacia (XLH), we compared the serum 1,25-dihydroxyvitamin D [1,25(OH)2D] level in 52 normal subjects and 37 patients with XLH. In untreated patients, adults were found to have values similar to age-matched controls, while youths had values similar to growth-rate-matched controls but significantly lower than the levels of age-matched controls who were growing at a normal rate. In contrast, treated XLH patients of all ages had serum levels significantly lower than both controls and untreated XLH patients. Further, the serum levels of 1,25(OH)2D in these treated patients had a significant inverse linear correlation with serum 25-(OH)D concentrations. We propose that subjects with XLH have serum 1,25(OH)2D levels within appropriate age- and growth-rate-matched normal ranges. However, in the presence of hypophosphatemia, we would have anticipated elevated levels of 1,25(OH)2D; viewed in this light the serum 1,25(OH)2D levels are inadequate, suggesting the presence of a relative deficiency of this active vitamin D metabolite.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411222
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  • 16
    Electronic Resource
    Electronic Resource
    Blood:Bone disequilibrium. V. Effects of a diphosphonate (EHDP) on phosphate fluxes in rat calvaria (1982)
    Springer
    Calcified tissue international 34 (1982), S. 145-148 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Diphosphonate ; Phosphate fluxes ; Solubility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Calvaria taken from rats (normal or thyroparathyroidectomized) given a diphosphonate (EHDP 10 mg/kg daily for 7 days) were placed in special Ussing chambers for the measurement of phosphate fluxes to and from bone. When compared with appropriate controls, the experimental calvaria showed a marked decrease in influx, K, a significant increase in the projected equilibrium concentration, E/K, where E is the efflux and a significnant increase in the calcium concentration in the medium. It is concluded that this large increase in passive “solubility” is caused by the diphosphonate's ability to stabilize the small amount of regulator phase (brushite or brushite-apatite mixture) present in bone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411225
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  • 17
    Electronic Resource
    Electronic Resource
    Parathyroid hormone and calcitonin interactions in bone: Irradiation-induced inhibition of escape in vitro (1982)
    Springer
    Calcified tissue international 34 (1982), S. 197-203 
    Details
    ISSN: 1432-0827
    Keywords: Parathyroid hormone ; Calcitonin ; Bone ; Escape ; Irradiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Calcitonin (CT) inhibits hormonally stimulated bone resorption only transiently in vitro. This phenomenon has been termed “escape,” but the mechanism for the effect is not understood. One possible explanation is that bone cell differentiation and recruitment of specific precursor cells, in response to stimulators of resorption, lead to the appearance of osteoclasts that are unresponsive to CT. To test this hypothesis, cell proliferation in neonatal mouse calvaria in organ culture was inhibited by irradiation from a cobalt-60 source. At a dose of 6000 R, [3H]thymidine incorporation into intact calvaria was inhibited approximately 90%. Irradiation had no effect on the resorptive response to 0.1 U/ml parathyroid hormone (PTH). However, irradiation induced a dose-dependent inhibition of the escape response which was maximal at 6000 R. A dose of 6000 R did not affect the binding of125I-salmon CT to calvaria and decreased PTH stimulation of cyclic AMP release from bone without affecting the cyclic AMP response to CT. Although irradiation caused a dose-dependent inhibition of DNA synthesis, the dose-response curves for that effect and inhibition of escape were not superimposable. A morphologic study of hormonally treated calvaria demonstrated that irradiation prevented the early increase in number of osteoclasts in PTH-treated calvaria that had been observed previously in unirradiated bones. Autoradiography showed that irradiation also prevented the PTH-stimulated recruitment of newly divided mononuclear cell precursors into osteoclasts. This may be correlated with the effect of irradiation to prevent the loss of responsiveness to CT in the presence of PTH.
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    URL: http://dx.doi.org/10.1007/BF02411233
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    Changes in plasma bone GLA protein during treatment of bone disease (1982)
    Springer
    Calcified tissue international 34 (1982), S. 121-124 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Calcium ; Metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Bone Gla protein (BGP) was measured in the plasma by radioimmunoassay (RIA) during treatment of 59 patients with bone diseases including Paget's disease (N=9), primary hyperparathyroidism (N=25), chronic renal failure (N=20), and cancer involving bone (N=5). Plasma BGP was increased above normal in all patients. BGP decreased in the patients with Paget's disease following the acute and chronic administration of salmon calcitonin. Plasma BGP was higher in women then in men with primary hyperparathyroidism. Following parathyroidectomy, BGP decreased in both sexes but the decrease was significant in women only. Plasma BGP was increased in patients with renal osteodystrophy and did not change after hemodialysis. In the patients with bone cancer, plasma BGP decreased during treatment of the attendant hypercalcemia with salmon calcitonin. Although plasma BGP and serum alkaline phosphatase (AP) levels were generally correlated in these studies, there were examples of dissociation between the two. The measurement of plasma BGP appears to provide a specific index of bone metabolism that may in some circumstances be more sensitive than serum alkaline phosphatase measurement. However, further studies are necessary to establish the clinical value of plasma BGP measurement by RIA in the management of patients with bone diseases.
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    URL: http://dx.doi.org/10.1007/BF02411221
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    Tensile properties of antler bone (1982)
    Springer
    Calcified tissue international 34 (1982), S. 301-305 
    Details
    ISSN: 1432-0827
    Keywords: Antler ; Bone ; Collagen ; Tension
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The tensile deformation characteristics of compact bone from deer antler were measured in both the “dry” and “wet” states and compared with published values for bovine compact bone. The tensile strength in the wet state (108±5.1 MN/m2) was comparable to the value for bovine compact bone tested at the same strain rate. The modulus value was very low: 7.5±0.9 GN/m2. The work to fracture was comparatively high, about 3 times that for bovine compact bone. Fractographic examination revealed fibrillar and osteonal shear for samples fractured in the dry state. In the samples tested in the wet state, some regions exhibited pull-out of lamellar segments from within a Haversian system. The results are explained in terms of the higher collagen content and lesser degree of mineralization in the antler.
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    URL: http://dx.doi.org/10.1007/BF02411255
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    The effects of long-term immobilization on the histomorphology of human cortical bone (1982)
    Springer
    Calcified tissue international 34 (1982), S. 337-342 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Histomorphology ; Immobilization ; Quadriplegia ; Multiple sclerosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The cortical bone histomorphometrics, total visible osteon density, and mean osteonal cross-sectional area were determined for the major long bones and sixth ribs of two individuals with neurological deficit. One was a multiple sclerosis patient who had been in a wheelchair for 15 years. The other was a quadriplegic as a result of poliomyelitis. Statistically significant differences in osteon densities occurred only in the case of the quadriplegic. Nevertheless, in that subject, the total visible osteon densities for bones of the right arm were not statistically different from those of their age-matched (control) radii. Medical history records revealed that there had been partial use of this limb. These results support the belief that mechanical stress is an important factor in the maintenance of normal cortical bone remodeling. In addition, since there were subnormal osteon densities and normal mean osteonal cross-sectional areas, immobilization appears to be characterized by reduced activation frequency with a normal amount of bone turnover per BMU.
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    URL: http://dx.doi.org/10.1007/BF02411264
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  • 21
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    Activation of serum complement inhibits collagen synthesis in fetal rat bone in organ culture (1982)
    Springer
    Calcified tissue international 34 (1982), S. 370-375 
    Details
    ISSN: 1432-0827
    Keywords: Complement ; Bone ; Collagen ; Prostaglandins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Activation of rabbit serum complement caused a marked reduction in collagen synthesis but a much smaller change in noncollagen protein synthesis in fetal rat calvaria maintained in organ culture. In the periosteum of the fetal rat calvarium, both collagen and noncollagen protein synthesis were reduced, whereas in the central bone, presumably enriched in osteoblasts, only collagen synthesis was inhibited. This large decrease in bone collagen synthesis could not be attributed to enhanced degradation of newly synthesized collagen or its release into the culture medium. Activation of complement also stimulated the production of PGE in fetal rat calvaria. Antagonists of prostaglandin cyclooxygenase decreased prostaglandin synthesis but did not restore collagen synthesis in complement-treated bones, suggesting that complement decreases osteoblast collagen synthesis by a mechanism largely independent of prostaglandin production.
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    URL: http://dx.doi.org/10.1007/BF02411270
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  • 22
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    Occurrence of actin-like protein in extracellular matrix vesicles (1982)
    Springer
    Calcified tissue international 34 (1982), S. 376-381 
    Details
    ISSN: 1432-0827
    Keywords: Matrix vesicles ; Bone ; Actin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Preliminary indications of the occurrence of actin and myosin in crude matrix vesicle preparations have been reported previously. In the present study extracellular matrix vesicles from rat alveolar bone were isolated. They were further purified by a sucrose density gradient. SDS-polyacrylamide gel electrophoresis of the purified vesicles revealed the presence of a polypeptide with a molecular weight of 43 K daltons and with electrophoretic mobility identical to that of blood platelet actin. The limited proteolysis of both 43 K dalton vesicular polypeptide and actin byStaphylococcus aureus-V8-protease revealed three fragments with identical electrophoretic mobility. In addition, the vesicular preparations inhibited the activity of DNase I, a property typical of actin monomers. Filamentous material extracted from matrix vesicles showed ultrastructural features of F-actin. Reaction of this material with heavy meromyosin resulted in arrowhead formation, which is characteristic of acto-heavy meromyosin. The occurrence of actin in extracellular matrix vesicles may account for their budding from the osteoblastic plasma membrane, their possible motility in the matrix, and maintenance of the spherical shape.
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    URL: http://dx.doi.org/10.1007/BF02411271
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    Abnormal skeletal response to parathyroid hormone in dogs with chronic uremia (1982)
    Springer
    Calcified tissue international 34 (1982), S. 403-407 
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    ISSN: 1432-0827
    Keywords: Cyclic AMP ; Parathyroid hormone ; Bone ; Chronic uremia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The release of cyclic AMP from bone in response to stimulation with PTH 1–34 was examined in 20 dogs with long-term chronic renal failure (CRF) produced by unilateral nephrectomy and contralateral partial renal artery ligation. After 9 to 15 months of uremia, the tibiae were removed and perfused in vitro. Seven dogs with CRF served as controls, 7 dogs with CRF were treated with 24,25(OH)2D3 — 2.5 µg per day, and 6 CRF dogs underwent thyroparathyroidectomy (TPTX) 42 h before they were sacrificed. The release of cyclic AMP from bone in response to PTH 1–34 in the CRF dogs was severely reduced compared to the response observed in 7 dogs with normal renal function (net accumulation of cyclic AMP release 86±8.5 versus 426±59.0 pmol/30 min). Long-term treatment of uremic dogs with 24,25(OH)2D3 had no effect on the release of cyclic AMP by bone. However, the release of cyclic AMP was restored to normal levels in the CRF dogs that underwent thyroparathyroidectomy. All CRF dogs had secondary hyperparathyroidism and the fact that TPTX returned the cyclic AMP response to normal values suggests that desensitization to PTH of the adenylate cyclase system of bone exists in chronic uremia.
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    URL: http://dx.doi.org/10.1007/BF02411275
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    A mathematical model for fluoride uptake by the skeleton (1993)
    Springer
    Calcified tissue international 52 (1993), S. 130-138 
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    ISSN: 1432-0827
    Keywords: Fluoride ; Bone ; Osteoporosis ; Bioavailability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A mathematical model was developed that prediets fluoride accumulation and clearance from the skeleton based upon fluoride bioavailability, bone remodeling rate, and the fluoride binding characteristics of bone. It was assumed that fluoride binds to bone in a nonlinear fashion such that a smaller percentage of fluoride is bound to bone if fluoride intake is increased to high levels. Bone resorption rate was assumed to be proportional to the solubility of hydroxyfluorapatite which is inversely related to bone fluoride content. The predictions made by the model compared favorably with experimental results from fluoride uptake and clearance studies. Parametric studies done using the model showed the following: (1) fluoride can be cleared from the skeleton by bone remodeling, but fluoride clearance takes over four times longer than does fluoride uptake; and (2) fluoride uptake by the skeleton was positively associated with bone remodeling rate. However, the concentration of fluoride in newly formed bone does not decrease with reduced remodeling rates and surpasses 10,000 ppm for intakes of fluoride greater than 9 mg/day. For osteoporosis, daily dose and duration of fluoride treatment should be selected to avoid reaching a toxic cumulative bone fluoride content.
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    URL: http://dx.doi.org/10.1007/BF00308322
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    The effects of diet, age, and sex on the mineral content of primate bones (1993)
    Springer
    Calcified tissue international 52 (1993), S. 399-405 
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    ISSN: 1432-0827
    Keywords: Rhesus monkey ; Bone ; Diet ; Age ; Sex ; Bone mineral
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The effect of diet, age, and sex on the mineral content of primate bones was determined for free-ranging rhesus monkeys (Macaca mulatta) from the Caribbean Primate Research Center. Monkeys in this study were of known age and sex and had been provided with either a low protein (15%) or a high protein (25%) diet for most of their lives. Instrumental neutron activation analysis was used to assess bone mineral content. Results showed that diet had no significant effect on the bulk mineral composition of Ca, Mg, Br, and Cl in the bones. Of the minerals analyzed, only Na and Mn showed significant diet-related effects. The bone Ca content was found to be lower in females than in males when controlled for age. Finally, Ca content was found to be higher in young adults, lower at middle age, and higher in old age in both male and female monkeys. In conclusion, this study has shown that increasing protein content in the diet does not change the bulk mineral content of primate bones. The nondietary effect that Ca content of monkey bones is lower during middle age has not been previously reported.
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    URL: http://dx.doi.org/10.1007/BF00310206
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    Histomorphometry of iliac crest trabecular bone in adult male baboons in captivity (1993)
    Springer
    Calcified tissue international 52 (1993), S. 447-454 
    Details
    ISSN: 1432-0827
    Keywords: Iliac crest ; Bone ; Histomorphometry ; Baboon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Dat in the literature on bone histomorphometry in the baboon are scant. This study provides data from analysis of trabecular bone of the iliac crest of 16 adult male chacma baboons (Papio ursinus) in captivity. Five animals were young adults judging by the presence of growth cartilage in the iliac crest biopsy. Bone volume resembled that in humans, but trabeculae were thinner and more closely spaced. Bone turnover appeared somewhat lower than in humans. Coupling of resorption and formation was excellent as judged by cellular and kinetic variables; erosion surface was an unreliable indicator of ongoing coupling. The similarities between human and baboon trabecular bone make the baboon suited for the study of microstructure and bone turnover of trabecular bone with relevance to humans.
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    URL: http://dx.doi.org/10.1007/BF00571335
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    Osteoclastic resorption of Ca-P biomaterials implanted in rabbit bone (1993)
    Springer
    Calcified tissue international 53 (1993), S. 348-356 
    Details
    ISSN: 1432-0827
    Keywords: Osteoclast ; Giant multinucleated cell ; Biomaterials ; Ceramics ; Morphometry ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The nature of the multinucleated cells involved in the resorption processes occurring inside macroporous calcium-phosphate biomaterials grafted into rabbit bone was studied using light microscopy, histomorphometric analysis, enzymatic detection of tartrate-resistant acid phosphatase (TRAP) activity, scanning, and electron microscopy. Samples were taken at days 7, 14, and 21 after implantation. As early as day 7, osteogenesis and resorption were observed at the surface of the biomaterials, inside the macropores. Resorption of both newly formed bone and calcium-phosphate biomaterials was associated with two types of multinucleated cells. Giant multinucleated cells were found only at the surface of the biomaterials; they showed a large number of nuclei, were TRAP negative, developed no ruffled border, and contained numerous vacuoles with large accumulation of mineral crystals from the biomaterials. Osteoclasts exhibited TRAP positivity and well-defined ruffled border. They were observed at the surface of both newly formed bone and biomaterials, around the implant, and inside the macropores. In contact with the biomaterials, infoldings of their ruffled border were observed between the mineral crystals, deeply inside the microporosity. The microporosity of the biomaterials (i.e., the noncrystalline spaces inside the biomaterials) increased underneath this type of cell as compared with underneath giant cells or to the depth of the biomaterials. These observations demonstrate that macroporous calcium-phosphate biomaterials implanted in bone elicit osteogenesis and the recruitment of a double multinucleated cell population having resorbing activity: giant multinucleated cells that resorb biomaterials and osteoclasts that resorb newly formed bone and biomaterials.
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    URL: http://dx.doi.org/10.1007/BF01351842
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    Osteocyte death and hip fracture (1993)
    Springer
    Calcified tissue international 53 (1993), S. S113 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Osteocyte ; Femoral neck fractures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The viability of osteocytes can be demonstrated in sawn decalcified sections of bone by their lactate dehydrogenase activity. In the cancellous bone of the femoral head, the proportion of lacunae containing viable osteocytes decreased from 88 ± 7% (mean ± SD) at 10–29 years to 58 ±12% (P 〈 0.001) by 70–89 years. Viability in the second lumbar vertebra was 88 ± 3% in subjects aged 25–90 years and did not decrease with age. Mean osteocyte viability in the femoral head of 21 hip fracture patients aged 72–94 years was 58 ± 21%, similar to controls of a similar age, though there was greater variation and, in five patients, osteocyte viability was less than 25%. In hip, fracture patients, microfracture callus incidence correlated positively with osteocyte viability, with little or no fracture callus observed if the bone viability was low. Ultimate compressive strength did not correlate with osteocyte viability. In the femoral head there is gradual, age-related reduction in osteocyte viability that can be more pronounced in hip fracture. Osteocyte death may affect bone quality by impairing repair of fatigue damage.
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    URL: http://dx.doi.org/10.1007/BF01673417
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    Expression of vigilin in chicken cartilage and bone (1993)
    Springer
    Cell & tissue research 273 (1993), S. 381-389 
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    ISSN: 1432-0878
    Keywords: Vigilin ; Cartilage ; Bone ; Differentiation ; In-situ hybridization ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The expression of vigilin was followed during chick embryonal development by in situ hybridization. Vigilin mRNA is abundantly expressed in tissues of mesenchymal and ectomesenchymal origin. The mesenchymal primordial cells of cartilage and bone did not show any significant, expression of vigilin. As tissue differentiation proceeded, vigilin mRNA levels increased in hyaline cartilage and in both endochondral as well as intramembranous bone. The results suggest that the expression of vigilin mRNA in cartilage- and bone-forming cells chondrocytes and osteobalsts, is dependent on the stage of development and cellular differentiation, although not a unique process of bone formation. Most striking is the correlation of the maximum vigilin mRNA expression in osteoblasts and hypertrophic chondrocytes to periods when cell-specific genes were highly transcribed and substantially translated, e.g., synthesis of procollagen and formation of extracellular matrix in bone and cartilage.
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    URL: http://dx.doi.org/10.1007/BF00312841
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    Transformation of fetal secondary cartilage into embryonic bone in organ cultures of human mandibular condyles (1993)
    Springer
    Cell & tissue research 271 (1993), S. 317-322 
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    ISSN: 1432-0878
    Keywords: Cartilage ; Bone ; Organ culture ; Joints ; Man (Primates)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Mandibular condyles of human fetuses, 14–21 weeks in utero, were kept in an organ culture system for up to 60 days. After 6 days in culture, the cartilage of the mandibular condyle appeared to have maintained its inherent structural characteristics, including all its various layers: chondroprogenitor, chondroblastic, and hypertrophic. After 12 days in culture, no chondroblasts could be seen; instead, the entire cartilage was occupied by hypertrophic chondrocytes. At the same time, the mesenchymal cells in the vicinity of the chondroprogenitor zone differentiated into osteoblast-like cells that produced type I collagen. The progenitor cells were still actively incorporating 3H-thymidine. The newly formed osteoid-like tissue lacked both metachromatic reactivity and a response to antibodies against chondroitin sulfate. Instead, the tissue reacted positively for osteocalcin (bone gla-protein). The process of new bone formation further progressed and, by the 20th day in culture, the new bone reacted positively for type I collagen, osteonectin, and to a lesser extent for chondroitin sulfate. The osteoid also underwent mineralization as revealed by both the von Kossa stain and vital staining with tetracycline. The above feature appeared even more intense in 40-day-old cultures. After 60 days, the newly formed bone contained osteoblasts and osteocytes, whereas the extracellular matrix revealed a high degree of matrix polarization. The results of the present study recapitulate findings reported for organ cultures of mice mandibular condyles. However, the in vitro process of de novo bone formation in human specimens requires a 6-fold longer culture time than that needed for mice condyles.
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    URL: http://dx.doi.org/10.1007/BF00318618
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    Fine structure of the developing frontal bones and scales of the cranial vault in the cichlid fish Hemichromis bimaculatus (Teleostei, Perciformes) (1993)
    Springer
    Cell & tissue research 273 (1993), S. 511-524 
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    ISSN: 1432-0878
    Keywords: Bone ; Scales ; Development ; Hemichromis bimaculatus (Teleostei, Perciformes)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The development of the frontal bone and the formation of the first head scales are described during post-embryonic ontogeny of Hemichromis bimaculatus, using light and transmission electron microscopy. The frontal bone originates close to the cartilaginous taenia marginalis in a loose mesenchymal cell condensation (=primordium) lying 1 μm from the epidermis with which it establishes no cell contacts. The anlage appears at 4.2 mm standard length (SL) in the form of the membranodermal component of the bone, and extends first over the brain and then over the eye; the neurodermal component forms later to surround the supraorbital canal. The first head scales appear at 10.0 mm SL in a dense cell condensation (papilla) adjoining the epidermal-dermal junction and, once formed, remain in this position. In both organs, the initial matrix is similarly composed of “woven-fibred” bone that soon mineralizes in a similar manner to other dermal elements. In some areas of the frontal bone, “parallel-fibred” bone is deposited unequally on both surfaces, whereas isopedine is deposited in scales on the deep surface only. Osteoblastic features confirm this eccentric growth. Differences in the shape, organization and localization of the mesenchymal condensations giving rise to the frontal bone and to the scale reflect the existence of two types of dermal cell condensations. Our data are compared with those available for the post-cranial dermal skeleton of fishes both from a developmental and structural viewpoint. Structural differences in the matrices of the frontal bone and scales are discussed in a phylogenetic perspective.
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    URL: http://dx.doi.org/10.1007/BF00333705
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    The human tibia: Static testing in bending by anin vivo method (1982)
    Springer
    Annals of biomedical engineering 10 (1982), S. 281-294 
    Details
    ISSN: 1573-9686
    Keywords: Tibia ; Strength ; Bone ; Elastic modulus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract We have developed a method for static testing of the human tibia in bending in the living subject, and fabricated a prototype device for carrying it out. Model testing indicates that the device and model system are inherently accurate and reliable. However, the biological system is more complex, and while more than 200 tests have been conducted with perfect safety, the variability of replicate tests suggests that the method does not yet have general clinical utility. In some subjects, that variance is relatively small, possibly because they are more relaxed and perhaps also for anatomical reasons. In two subjects, postmortem tests corresponded very well with antemortem tests on the tibiometer. We conclude that with further refinements the method may have clinical potential, if only in carefully selected subjects.
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    URL: http://dx.doi.org/10.1007/BF02367309
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    Effect of ultraviolet light on the dielectric behavior of bone at microwave frequencies (1982)
    Springer
    Annals of biomedical engineering 10 (1982), S. 139-144 
    Details
    ISSN: 1573-9686
    Keywords: Dielectric constant ; Bone ; Collagen ; Apatite
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract The dielectric constant of bone and its two components (collagen and apatite) were determined at 9.2 GHz in a room temperature environment by the cavity perturbation technique. After samples were exposed to ultraviolet light, repeat measurements under identical conditions showed decreases in both the real and the imaginary parts of the dielectric constant in all cases. The present work describes the technique and a possible mechanism of ultraviolet interaction with bone.
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    URL: http://dx.doi.org/10.1007/BF02367462
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    Magnetic and electric fields produced during pulsed-magnetic-field therapy for non-union of the tibia (1982)
    Springer
    Medical & biological engineering & computing 20 (1982), S. 501-511 
    Details
    ISSN: 1741-0444
    Keywords: Bone ; Electric fields ; Magnetic fields ; Pulsed-magnetic-field therapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Pulsed-magnetic-field therapy for non-union of the tibia is becoming, in some centres, an established orthopaedic technique. The field is generated by passing pulses of current through coils positioned around the leg, but the mechanism of interaction is not understood. This paper gives a qualitative description of the fields produced and then develops a theoretical model to calculate the fields for simple geometries. Good agreement is found between calculation and measurement, validating the model and showing that the form of the fields produced in a limb can now be described.
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    URL: http://dx.doi.org/10.1007/BF02442413
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