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The most prominent effect of propane-2, 2-diphosphonate (PDP) and ethane-1-hydroxy-1, 1-diphosphonate (EHDP) on matrix-induced ectopic bone in the rat was a dose-dependent inhibition of osteogenesis in the early phases of development. The delay was seen as a consequence of osteoprogenitor cell inhibition. Additionally, later phases of bone maturation were disturbed by interference with the mineralization and remodeling processes. However, direct effects on the calcium phosphates of bone are only of minor additional value, which remains of lesser importance in comparison to the cellular impairment. After withdrawal of diphosphonates, the effects were nearly completely remitted. Neither PDP nor EHDP, even given in high doses, resulted in a lasting reduction in ectopic mass. The remission may be referred to the recovery of cell activities, whereas the mineral impregnation of osteoidosis was, if at all, of little importance. For treatment of ectopic osteogenesis PDP proved inefficient.

Collagen was extracted from human adult bone by limited pepsin digestion and collagen types were purified by consecutive salt precipitation first under neutral and then under acid conditions. In SDS/PAGE, all collagen type I preparations showed a protein band [alpha 1s(I)] migrating between alpha 1(I) and alpha 2(I) as well as a band [alpha 2s(I)] migrating in front of alpha 2(I). The collagenous nature of the pepsin-stable alpha 1s(I) protein was clearly demonstrated by digestion with human-leucocyte-derived collagenase, immunoblotting with antibodies against collagen type I and amino acid analysis. Partial amino acid sequencing of alpha 1(I) and alpha 1s(I) identified alpha 1s(I) as a shortened alpha 1(I) chain due to a specific cleavage site between residues Leu95 and Asp96 which is in close vicinity to the hydroxylysine-derived crosslink at position 87. In circular dichroism, the proportion of thermally labile collagen molecules was proportional to the amount of shortened alpha 1(I) and alpha 2(I) chains, respectively. The melting temperature was found to be 36 +/- 0.5 degrees C as judged from circular dichroism and susceptibility to proteolysis. Our data provide clear evidence that a shortened alpha 1-derived collagen chain can be extracted from human adult bone whereas it is hardly found in human skin. The unique cleavage site might provide important information about the collagen I molecule embedded in the calcified matrix of human bone.

Two healthy individuals who drank water accidentally contaminated at source with aluminium sulphate solution were investigated 6-7 months later. Bone biopsy specimens showed discrete lines of positive staining for aluminium, the distribution being compatible with acute exposure some months previously. These findings show that under certain conditions normal individuals can absorb aluminium via the gut, and that such aluminium can be deposited in bone.

Localization of bone morphogenetic protein (BMP) in human tissues and cells is important for investigating the mechanism of bone induction. A stable cell line secreting monoclonal antibody against bovine BMP (bBMP-McAb) was obtained by the hybridoma technique. The result of immunohistochemical staining (ABC method) showed that BMP is distributed along collagen fibers of normal bone, in periosteal cells, and in mesenchymal cells of marrow stroma. Little BMP can be found in bone cells of lamellar bone or in calcified bone matrix. BMP may be abundant in human tooth anlagen such as predentin, cells of the outer and inner enamel epithelium, and cells of dental sac generating bone. BMP is found in the cytoplasm of tumor cells of osteosarcoma and chondrosarcoma. Immunohistochemical staining showed that BMP plays a role in bone fracture healing. The ability of BMP-McAb to detect BMP and to inhibit the generation of new bone also makes it potentially useful in diagnosing, treating, and providing a prognosis for osteosarcoma and other bone diseases.

Radithor was a radioactive patent medicine that was touted as a metabolic stimulant and aphrodisiac. We have obtained several original samples of Radithor and have used these historical specimens and a computer-based calculation model to perform a retrospective analysis of a famous case of Radithor-related radium poisoning. Our data suggest that the victim's cumulative skeletal radiation dose may have exceeded 350 Sv by the time he died. This figure far exceeds most current estimates of what radiation exposure level would constitute a rapidly lethal dose if given acutely. The physiological response to longterm internal radiation exposure and the highly localized nature of alpha particle irradiation may require the development of new models for the assessment of risk in cases of internal alpha particle irradiation.

This study explores the effects of a calcium-deficient diet on patterns of bone remodeling, and examines regional differences in the amount of bone lost. Skeletally mature female rabbits (n = 6) were fed a calcium-deficient diet (0.10% Ca2+ and 0.50% P) for 14 weeks. A separate group of rabbits (n = 4) were fed a maintenance diet (1.2% Ca2+ and 0.45% P). Bone mineral content, serum calcium, and serum phosphorus were measured each week during the experimental period. Following sacrifice, the L3 vertebra, femoral head, proximal tibial metaphysis, and tibial midshaft were analyzed histomorphometrically. Rabbits had 20% less vertebral bone after only 14 weeks of a calcium-deficient diet. As in human postmenopausal osteoporosis, bone loss in calcium-deficient rabbits occurs in the trabecular bone of the lumbar spine before that in the trabecular bone of the lower extremity. Calcium-deficient diets alone do not lead to increased osteoid volume or thickness. Because bone loss is relatively rapid and because the pattern of loss is similar in some respects to that found in humans, adult rabbits may provide an attractive model of calcium deficiency osteoporosis in a skeletally mature mammal in which remodeling is predominant over modeling.

Thermostimulated current spectroscopy has been applied to the investigation of molecular mobility in human calcified tissue. A comparative study of extracts at various stages of demineralization is presented. The response of an organic-mineral complex interphase has been identified.

A comparison between the effect of low molecular weight heparin (LMWH) and unfragmented heparin (UH) on induction of osteoporosis was made in 60 rats treated with either UH (2 IU/g bw), LMWH in 2 doses (2 XaI U/g or 0.4 XaI U/g) or placebo (saline) for 34 days. Studied variables were: bone mineral mass in femora; fragility of humera; zinc and calcium levels in serum and bone ash and albumin in plasma. A significant reduction in bone mineral mass was found in all heparin-treated rats. There was no difference between UH and LMWH in this respect. The effect was dose-dependent in LMWH-treated animals. The zinc contents in bone ash were decreased in all heparin-treated rats as compared with controls. No recognizable pattern was seen in alterations of zinc or calcium in serum. The fragility of the humera, tested as breaking strength did not differ between treatment groups and controls. In conclusion, if dosed according to similar factor Xa inhibitory activities, LMWH induces osteoporosis to the same extent as UH and in a dose-dependent manner. The zinc content in bone ash was decreased after heparin treatment, irrespective of type of heparin given.

By means of light, scanning and transmission electron microscopy structure of the mineral phase of human compact bone have been studied. Mechanical properties of deorganified bone samples have been determined. High compressive strength may be in connection with interactions of plate-like mineral particles at the level of hydrate shell of the bone mineral crystallites.

Many methods are used to determine bone mineral content (BMC). Quantitative computed tomography (QCT) appears to be the most reliable method also because it allows the trabecular and the cortical bone to be measured separately. QCT is usually performed on the first four lumbar vertebral bodies. BMC is expressed in mg/ml and a mean value is calculated. Three hundred and fifteen subjects were studied (281 women and 34 men). The patients affected with Paget's disease or malignancies, with or without bone metastases, were not included in this study. The measurements were performed by means of a General Electric 9800 tomograph with software and calibration phantom (QCT-Bone program by Image Analysis). Fractured vertebrae were not included when calculating the mean value since an increased density is caused by fracture. The BMC of any studied vertebral body is considered in comparison with the BMC of the other lumbar vertebrae of the same subject. When the BMC of a given vertebral body exceeds the others by 25 mg/ml or more, nodules and/or stripes are observed during multiple-slice scanning of the bone. Lytic areas or angiomas are observed when the BMC of a given vertebral body is -25 mg/ml or higher. In calculating the mean vertebral BMC, vertebrae with both +25 and -25 must be excluded. In this way the method reliability increases.

Sites of ectopic ossification (EO) due to sports injury in a long-distance runner were biopsied and analyzed. The mineral content was compared to that of normal adult bone and to paraosteoarthropathy (POA) using biophysical methods. The degree of mineralization of bone tissue (DMBT) was employed as an evaluation of maturity of calcified tissue. Fluoride and carbonate content were determined. The crystal lattice dimensions expressed by the a and c parameters, crystal size, and/or lattice perfection were obtained with x-ray diffraction. All values were near those found in nonpathologic, newly deposited human compact bone. DMBT, crystal size, and/or lattice perfection were near those observed in a 24- to 30-month-old POA. The data suggest that posttraumatic EO represents otherwise normal young bone.

Human population history is firmly connected with temporal and regional changes of the environment. Whether natural or anthropogene, alteration of environmental features lead to changes of human life-style and to the development of adaptive strategies. The demand of resources for his subsistence has led man to diverse impacts on his environment since ever. Thus, environmental history is a scientific topic for anthropologists. The research potential of trace element studies of excavated human skeletons for the reconstruction of natural and socio-cultural environments as well as for distribution patterns of hazardous substances is outlined for the European Middle Ages. The scientific value of unravelling past man/environment-interrelationships for both the historical and applied sciences and the place of any "chemical anthropology" within this context is discussed.

Progressive bone loss in osteoporosis results from bone resorption in excess of bone formation. We conducted a double-blind study in 66 women with postmenopausal osteoporosis of therapy with etidronate, a diphosphonate compound that reduces bone resorption by inhibiting osteoclastic activity. The patients were randomly assigned in equal numbers to receive oral etidronate (400 mg per day) or placebo for 2 weeks, followed by a 13-week period in which no drugs were given. This sequence was repeated 10 times, for a total of 150 weeks. Daily oral supplementation with calcium and vitamin D was given throughout the study to both groups. Vertebral bone mineral content was measured by dual-photon absorptiometry; spinal radiographs were assessed to identify new vertebral fractures. Vertebral bone mineral content increased significantly (P less than 0.01) after 150 weeks of etidronate therapy (5.3 percent; 95 percent confidence interval, 2.0 to 8.6; n = 20) but decreased with placebo (-2.7 percent; 95 percent confidence interval, -7.3 to 1.9; n = 20). The difference between groups was 8.0 percentage points (P less than 0.01; 95 percent confidence interval, 2.4 to 13.6). The rates of fracture were significantly different for the period from week 60 to week 150 between the etidronate and placebo groups (6 vs. 54 fractures per 100 patient-years; P = 0.023). No adverse clinical, biochemical, or bone histomorphometric effects of treatment were observed. We conclude that at the end of nearly three years, etidronate therapy for postmenopausal osteoporosis results in significant increases in vertebral bone mineral content and, after approximately one year of treatment, a significant decrease in the rate of new vertebral fractures.

Bone disorders in 28 children with chronic renal failure exposed to aluminum intoxication were studied. All of the children were in the dialysis program. Aluminum blood levels were higher than normal in all of the children and without any correlation to the magnitude of hypocalcemia or with the increase of the parathormone, which were found in different amounts in all of the children. All of the children had various degrees of skeletal retardation and only one had pathological fractures. The bone biopsy showed hypocellular marrow, decreased osteoclastic activity in the majority of the cases same as trabecular mineralization, although the amount of osteoid was lacking in the trabeculae in the majority of the cases. The deposit of aluminum was detected in a great number of them. It is concluded that osteodystrophy recognizes a number of factors as may be hypocalcemia due to a decrease in the production of 1,25-cholecalciferol, an increase in the parathyroid hormone and the deposit of aluminum, coming mainly from water, in the trabeculae which interfere with the incorporation of calcium in the formation of new bone.

Bone Gla protein (BGP) is a vitamin K-dependent protein which is a marker of bone turnover. To determine whether serum BGP is a useful indicator for parathyroidectomy in patients with secondary hyperparathyroidism, we measured serum BGP levels. Thirty-seven patients with secondary hyperparathyroidism who were followed up for more than 1 year after parathyroidectomy were studied. All patients underwent total parathyroidectomy and autotransplantation. Controls were 46 patients who were treated by chronic hemodialysis for more than 3 years. Serum BGP levels (normal: less than 6.5 ng/ml) were markedly increased in 37 patients with parathyroidectomy, ranging from 4.2 ng/ml to 645 ng/ml, with a mean value of 278.8 +/- 159.8 ng/ml (mean +/- standard deviation) versus 65.0 +/- 85.2 ng/ml in the 46 controls (p less than 0.001). Patients with a high BGP level had severe bone and joint pain. Serum BGP in patients with parathyroidectomy was significantly correlated with serum alkaline phosphatase and mPTH (p less than 0.001 for both). The total weight of resected parathyroid tumors was 2,152 +/- 1,368 mg, and tumor weights ranged from 200 mg to 5,600 mg. There was a highly significant correlation between BGP level and tumor weight (r = 0.656, p less than 0.001). The 2 patients who showed BGP levels below 10 ng/ml had tumor weights of only 470 mg and 240 mg, respectively, and revealed no improvement of pain postoperatively, although their mPTH levels were increased. These results suggested that BGP measurement is a sensitive method for detecting increased bone turnover and is possibly useful as an indicator for parathyroidectomy in patients with secondary hyperparathyroidism.

A series of calcium phosphate standards having calcium/phosphorus (Ca/P) molar ratios of 0.50, 1.00, 1.50, and 1.67, respectively, was prepared for bulk specimen analysis using scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDXA). The standards were mounted on carbon planchettes as either pure crystals or crystals embedded in epoxy resin. Ten different samples of each embedded and non-embedded standard were analyzed in a JEOL 100 CX electron microscope interfaced with a Kevex 8000 EDXA system using a lithium-drifted silicon detector and a multichannel analyzer. The Ca/P ratios were determined by calculating both net peak intensities without matrix corrections and atomic kappa-ratios using the MAGIC V computer program with ZAF correction factors for quantitative analysis. There was such extensive absorption of phosphorus X-rays in standards embedded in an epoxy matrix that the observed Ca/P ratios were statistically compatible with four different standards ranging in theoretical Ca/P ratios from 1.0 to 1.67. Although the non-embedded crystals showed a greater separation in the Ca/P ratios, both methods of preparation produced serious flaws in analysis. Direct application of the discovery of this caveat to the identification of suspected bone fragments for forensic science purposes is discussed.

The concentrations of ciprofloxacin produced in bone, cartilage and menisci after a single administration of 200 mg were determined at different intervals in a group of patients with an average age of 80 years. Concentrations of 0.11 to 0.94 mg/kg bone tissue were measured after 0.5 to 5 hours. In the cartilage a concentration of active substance was measureable only once (4.18 mg/kg). In the presence of marked circulatory disorders the active substance concentrations reached in the bone were above those found in the seriously damaged muscle. Although the concentrations reached in the bone are effective, no risk should be taken in osteomyelitis. Ciprofloxacin should therefore be used at high dosage and possibly be combined with another substance. Given for therapeutic purposes, a single dose of ciprofloxacin is naturally not effective enough, and given for prophylactic purposes, not safe enough to prevent a post-traumatic osteitis.

A colorimetric method for the detection of gamma-carboxyglutamic acid (Gla)-containing proteins after reaction with 4-diazobenzenesulfonic acid is presented. Proteins can be visualized after electroblotting from polyacrylamide gels onto membrane supports, after dot-blotting onto membranes, or in solution as a red colored product with an absorbance maximum at 530 nm. The method is specific since other proteins without gamma-carboxyglutamic acid do not form a red color. The presence of other proteins does not inhibit or affect color production by gamma-carboxyglutamic acid-containing proteins. Application of the method for staining a Western blot of a crude extract of bone resulted in staining of only the gamma-carboxyglutamic acid-containing proteins. The usefulness of the method was verified when a second gamma-carboxyglutamic acid-containing protein, prothrombin, also resulted in red color production. A linear color response is seen up to 17 microM for the gamma-carboxyglutamic acid-containing protein bone Gla protein and up to 27 microM for the amino acid. The detection limit is down to 1 microgram of bone Gla protein or 0.17 nmol of the protein on electroblots or dot blots. The simplicity of the method allows rapid screening for gamma-carboxyglutamic acid-containing proteins or allows monitoring of purifications of these proteins in chromatographic or electrophoretic separations.

Assessment of potential aluminum loading from regular ingestion of a commercial infant formula (Similac PM 60/40), as the only milk substitute, was made in 14 infants aged 9.6 +/- 4.4 months who were also undergoing continuous cycling peritoneal dialysis. Tissue aluminum accumulation was assessed by serial measurements of plasma aluminum levels, from the increment in plasma aluminum after a standardized deferoxamine infusion, and from quantitative histomorphometry of bone and measurements of total bone aluminum content. Initial mean plasma aluminum levels were 0.61 +/- 0.32 mumol/L, (normal 0.30 +/- 0.04 mumol/L), and values were less than 0.92 mumol/L during the follow-up of 20 +/- 8 months. Plasma aluminum levels increased from 0.59 +/- 0.18 to 0.88 +/- 0.22 mumol/L after a single dose of deferoxamine. The histochemical stain for bone aluminum was negative for all patients, and the bone aluminum content was 0.27 +/- 0.22 mmol/kg dry weight (normal 0.08 +/- 0.04 mmol/kg dry weight). Thus the infant formula Similac PM 60/40 can be safely used in infants with chronic renal failure.

In chronic renal failure, aluminum overload may influence parathyroid function. In a study of possible aluminum-induced parathyroid abnormalities, parathyroid glands from nine parathyroidectomized patients on hemodialysis were examined by light and electron microscopy and by X-ray microanalysis. Aluminum overload was assessed by the presence of stainable aluminum (aluminum surface, 23.3% +/- 11% of total surface) in bone biopsy specimens. The mean plasma aluminum concentration was 7.7 +/- 1.9 mumol/L. All patients but one had elevated plasma concentrations of immunoreactive parathyroid hormone as well as osteitis fibrosa. The aluminum concentrations in bone and parathyroid gland from these patients were significantly higher than those in tissue from patients on hemodialysis without stainable bone aluminum. Abundant aluminum deposits were present in parathyroid chief cell cytoplasm in lipoid bodies, lipofuscin granules, and mitochondria. These cells exhibited features of active hormonal synthesis and contained numerous secretory granules. The data show that in the parathyroid glands of these aluminum-intoxicated patients the presence of aluminum deposits neither induced cellular damage or chief cell necrosis nor interfered with the production of parathyroid hormone.

This study was performed to determine the long-term effects of dietary aluminum on egg production and reproductive parameters in the mature laying hen and on growth rate and feed efficiency in young chicks. The diets used in these studies were adequate in phosphorus and other essential nutrients. Aluminum added to constitute 0.30% of the diet severely depressed growth and reduced feed efficiency, bone ash and plasma phosphorus in male Ross x Leghorn chicks. At the same time, 0.15% added aluminum mildly depressed growth, feed efficiency and bone ash but had no effect on plasma phosphorus levels. The reduction in bone ash was relatively mild, and no clinical signs of rickets were observed. In laying hens, diets containing 0.15% added aluminum did not affect egg production, but 0.30% added aluminum reduced production significantly. Long-term exposure to aluminum increased percent shell in both groups receiving aluminum, whereas egg weight remained similar to that in controls. There were no changes in hatchability or bone ash associated with dietary aluminum. Although dietary aluminum influenced bone aluminum content, egg aluminum content was not affected. These studies indicate that dietary aluminum interferes with systems in addition to phosphorus metabolism.

The non-collagenous proteins of mature cortical rabbit bone and 3 wk old bone specimens formed in titanium implant bone harvest chambers, were separated by means of fine pressure liquid chromatography. It was found that a sufficient amount of bone could be obtained from five bone harvest chambers in five rabbits during a period of 15 wk. A different protein chromatographic pattern was found in bone grown in bone harvest chambers as compared to normal cortical bone from the same region. This indicates a difference in bone quality and shows that this implant design can be used for biochemical analysis of bone formed adjacent to a biomaterial.

Effects of dietary P on breaking load and chemical properties of bone were evaluated in growing beef heifers. Initially, 14 weaned Angus heifers received ad libitum a low P diet (.10% P dry basis) for 270 d. Heifers were subsequently randomly allotted into two groups (7 heifers/group) and received ad libitum either .12 or .20% P (dry basis). The experimental endpoint was 245 d of the treatment phase for nonpregnant and 3 wk postpartum for pregnant heifers. Results indicate that chemical and physical properties of bovine bones are sensitive to dietary P. Mineralization of rib bones was less at .12% P (dry basis). Rib bone density (g/cm3) and mineral content expressed on a per unit volume basis (mg/cm3) were the most sensitive parameters measured. Breaking load results of 12th ribs also indicated a greater amount of mineral present in heifers receiving .20% P (153.8 vs. 114.3 kg). Vertebral bone density and mineral concentrations on a per unit volume basis were also sensitive to dietary P and clearly ranked the two dietary P amounts, whereas percentage of bone ash or mineral concentration expressed on an ash basis did not.

Fourteen individuals on long term hemodialysis, with varying amounts of aluminum in bone from 11 to 296 mg/kg by flameless atomic absorption spectrophotometry, were examined to see whether the aluminon or acid solochrome azurine (ASA) staining reactions best approximated the chemical determination. Correlation coefficients were 0.78 for aluminon and 0.88 for ASA. Together with 11 additional patients morphometric parameters were compared with the two aluminum stains. The aluminon stain gave satisfactory results in the osteomalacic group but underestimated the amount of aluminum present in those with hyperparathyroid, mixed or aplastic disease. Some individuals showed a striking difference between the two techniques which could have led to an erroneous conclusion regarding the amount of aluminum present. The aluminon stain was pH dependent and together with ASA could be enhanced by prior heat treatment of the sections. It is recommended that ASA either replace aluminon for routine use or be used together with the aluminon stain, particularly for bones without osteomalacia or with mild to moderate aluminum storage.

The use of lectins in histochemical research substantially contributed to the knowledge on carbohydrates. This paper is a preliminary report of findings with lectin histochemistry on normal and pathological bone tissue.

The metabolism of Mg was studied in young dairy calves fed two levels of added Al (0 and .20% Al) and two levels of added P (0 and .22% P) for 7 wk. The four treatments were 1) normal P-low Al, 2) low P-low Al, 3) normal P-high Al and 4) low P-high Al. The basal diet (low P-low Al) contained, by analysis, .132% P, .021% Al and .17% Mg. Added Al did not affect (P greater than .10) serum Mg. An Al x P interaction on bone Mg was detected (P less than .01). Magnesium was reduced in tibia shaft (.34 vs .44%) and in tibia joint (.43 vs .53%) in calves fed high Al in the presence of normal dietary P, but Mg was not reduced in the calves fed low-P diets. Apparent absorption of Mg was reduced by approximately five-fold (.18 g/d vs -.84 g/d, P less than .01); urinary Mg excretion was reduced 31% (1.12 g/d vs .77 g/d, P less than .01); and Mg retention declined 41% (-95 g/d vs -1.61 g/d, P less than .01) in calves fed added A1. Compared with calves fed low-P diets, calves fed normal levels of P had a higher Mg concentration in tibia shaft (P less than .01) and tibia joint (P less than .05). The data indicate that supplemental Al may adversely affect Mg metabolism in calves.

To assess the changes in bone mineral density and osteoblastic activity in patients with hyperthyroidism and to investigate the relationship between those changes, we measured bone mineral density and serum osteocalcin in 109 patients with Graves' disease, comprising 75 untreated patients and 34 patients under treatment, and 200 normal controls. The degree of change in bone mineral density was quantified with Z transformation, in which we used means and SDs of bone mineral densities obtained in the process of age- and sex-matched 1:1 pairing developed by ourselves. Bone mineral density was low in female patients with hyperthyroidism in the spine, femur neck, trochanter, and Ward's triangle, but was not low in male patients. Serum osteocalcin was elevated in patients with untreated Graves' disease and correlated negatively with the Z values of bone mineral densities of the spine, femur neck, and trochanter. In conclusion, indices of osteoblastic activity were elevated in patients with hyperthyroidism, probably secondary to a thyroid hormone-induced increase in bone resorption which resulted in reduced bone mineral density. Quantification of the change in bone mineral density by using the parameters derived in the process of age- and sex-matched pairing seems to be an efficient method for statistical analyses.

1. Oestrogen target cells in the medullary bone of laying hens were examined using a histochemical method with fluorescein isothiocyanate labelled oestradiol. 2. Specific fluorescence was found to occur strongly in osteoblasts and weakly in osteoclasts on the medullary bone surface. 3. This study suggests that osteoblasts on the medullary bone surface are oestrogen target cells.

Aluminium-related osteodystrophy results in osteomalacia or in the so-called aplastic bone. In this particular bone disease bone cells activities are distinctly reduced but there is no disorder of bone mineralization. Aluminium exerts a direct toxic effect on bone tissue, notably on osteoblasts which are always strongly depressed in case of major aluminium overload. Aluminium-related osteopathy is regularly accompanied by low levels of parathormone due to accumulation of aluminium in the parathyroid glands. Parathormone modulates the bone aluminium overload: hyperparathyroidism "protects" bones against the deleterious effect of aluminium, whereas aluminium deposit in bone increase after parathyroidectomy. The respective roles played by low parathormone levels and by aluminium deposits in aplastic bone lesions is difficult to determine since hypoparathyroidism itself can probably cause the aplastic osteopathy. The role of parathormone stands out more clearly now that in patients under dialysis the bone aluminium overload has markedly decreased. Many patients with aplastic bone (initially described in aluminium poisoning) show no aluminium deposits in bones but have, for some unknown reason, a normal or even low parathormone level. The clinical course of this type of osteopathy remains to be determined, but there seems to be no reason to worry since numerous patient are asymptomatic. Preventing secondary hyperparathyroidism while refraining from prescribing aluminium hydroxide is the principal therapeutic objective in osteodystrophy of haemodialysis patients.

The incidence of aluminium osteomalacia (ALO) in patients with chronic renal failure neither on dialysis nor taking aluminium-containing phosphate binders (ACPB) is not well documented. Biochemical and histological bone investigations were performed in 35 patients fulfilling the above conditions, among whom we found an incidence of ALO of 17%. In the ALO group, salient findings were PTH level (mean +/- s.d.) of 3.1 +/- 1.4 ng/ml (normal less than 0.5 ng/ml); elevated home tap-water aluminium levels of 6.5 +/- 1.2 umol/l (normal less than 2 umol/l); and a GFR of 20.5 mls/min/1.73m, (range 2-50 mls/min/1.73m). We conclude that the aetiology of ALO in this group involves the absorption of toxic home water aluminium in the presence of an elevated PTH level and a GFR less than 50 mls/min/1.73m.

The present study was undertaken to determine the fluoride distribution profile in the rat femur. Male Wistar rats were divided into four groups and given water containing 0, 25, 50, and 100 ppm of fluoride, respectively, for 10 weeks. The fluoride distribution from the periosteum to the endosteum was determined in each specimen after sampling using the abrasive microsampling technique. In the outer circumferential lamellae, the concentration of fluoride was relatively high in the periosteal layer and then decreased gradually towards its interior. In the haversian and interstitial lamellae, it was lower and roughly constant through the tissue. In the inner circumferential lamellae, it rose again to reach the highest level towards the endosteal surface. Fluoride concentration throughout the cortex increased significantly with increasing intake of fluoride. These increases were especially marked at periosteal and endosteal surfaces.

A desferrioxamine (DFO) infusion test, using a DFO dose of 36.9 +/- 11.2 mg/kg (mean +/- SD), was performed in 50 consecutive dialysis patients undergoing diagnostic bone biopsy. In 30 patients whose bones stained positively for aluminium the serum aluminium level increased by an average of 373 +/- 250.4 ng/ml. The increase in 20 aluminium-negative patients was 231 +/- 179.2 ng/ml (p less than 0.05). Aluminium-positive patients had lower levels of immunoreactive parathyroid hormone (336 +/- 442 muleq/ml) than aluminium-negative patients (1278 +/- 1400 muleq/ml; p less than 0.05). A change in serum aluminium level of greater than 200 ng/ml after the administration of DFO was 73 percent sensitive and 50 percent specific, and had a positive predictive value of 69 percent for detecting positive bone aluminium staining. The combination of a baseline immunoreactive parathyroid hormone level less than 200 muleq/ml and a change in serum aluminium of greater than 200 ng/ml after DFO was 90 percent specific and had a positive predictive value of 85 percent. In the second phase of our study, 28 dialysis patients with aluminium toxicity received long-term therapy (11.0 +/- 4.3 months) with DFO at an average starting dose of 41.7 +/- 17.1 mg/kg, administered once weekly. The four deaths which occurred during this treatment involved the only patients who had advanced dialysis dementia. Seven patients with less severe neurological symptoms responded favourably. Fractures decreased from 1.7 fractures/patient/year to 0.1 fracture/patient/year. Muscular strength and overall functional class were improved or stable in 25 patients; myalgias and arthralgias were also stable or improved in 19 patients. After 5-7 months of treatment, serum aluminium levels decreased from 401 +/- 262 ng/ml to 245 +/- 217 ng/ml (p less than 0.01); erythrocyte mean corpuscular volume increased from 86.3 +/- 10.91 fl to 94.1 +/- 9.23 fl (p less than 0.02); and serum calcium decreased from 10.4 +/- 0.94 mg/dl to 9.9 +/- 0.70 mg/dl (p less than 0.02). Serum immunoreactive parathyroid hormone levels remained stable in 25 patients, but severe hyperparathyroidism developed rapidly in three patients. Eight patients with transfusional iron overload had no change in serum ferritin levels. Iron depletion developed in six patients, with a decrease in serum ferritin from 251 +/- 229.8 micrograms/l to 45 +/- 29.3 micrograms/l, and they required parenteral iron supplementation. Significant side-effects occurring during long-term DFO administration were hypotension (11 patients), gastrointestinal upset (seven patients), porphyria cutaneous tarda-like lesions (three patients), and transient visual disturbance (one patient). There was a decrease in stainable bone aluminium in all nine patients with paired bone biopsy specimens (pre- and post-DFO).(ABSTRACT TRUNCATED AT 400 WORDS)

We measured bone osteocalcin concentrations in EDTA extracts from iliac crest cortical bone specimens obtained postmortem from 63 men and 71 women (age range 19-90 years), and serum osteocalcin levels in healthy blood donors, 49 men and 49 women (age range 21-65 years). Bone and serum osteocalcin concentrations were higher in men than in women, and an age-related decline was observed in both sexes. In women, however, a temporary increase in serum (P less than 0.05) osteocalcin was seen in the sixth decade. This study shows sex- and age-related changes in bone osteocalcin consistent with changes in serum osteocalcin, confirming that serum measurement of osteocalcin reflects bone levels. As osteocalcin reflects osteoblastic activity and thus bone formation, the overall decline in bone and serum osteocalcin in men and women, and the increase in serum osteocalcin in the sixth decade in women, indicate that aging is associated with a decrease in bone formation and turnover and that osteoblastic activity and bone turnover are stimulated at the menopause.

19F free induction decay (FID) signals have been observed from the index fingers of four male and two female adult volunteers using a 27-MHz pulsed nuclear magnetic resonance spectrometer equipped with a split ring resonator probe. The value of the in vivo spin-lattice relaxation time T1 of the fluoride ions naturally accumulated in bone mineral has been determined to be 2.0 +/- 0.3 s. The shape of the observed FID signals in the inhomogeneous external magnetic field indicates that the F distribution is not uniform along the length of the finger. The fluoride ion content of the index finger (within a 65-mm length from its distal end) was measured with a sensitivity of +/- 0.5 mg F within a 30-min observation time.

It was previously shown that 11 months after ovariectomy the volume fraction of trabecular bone in the spine and 11th rib medullary canal of Beagle dogs (6 control, 9 ovariectomized) was significantly reduced. In this paper it is shown that these changes are accompanied by increased marrow fat volume in the 11th rib (59.0 +/- 9.5% vs. 44.3 +/- 10.0%). Conversely, the volume fraction of functional (hematopoietic) cells in the marrow was reduced by ovariectomy. Additionally, variations in marrow fat volume were tested for correlation with 22 other variables pertinent to bone physiology. Marrow fat volume was significantly positively correlated with serum osteocalcin, rib trabecular bone porosity, rib cross-sectional area, and gains in body weight. It was negatively correlated with serum estrogen concentrations and the extent of rib trabecular surfaces labeled with tetracycline.

When the aluminium content of the water supply to our Haemodialysis Unit rose from less than 0.5 mumol/l to 6 mumol/l over a two month period, we carried out bone biopsies and desferrioxamine infusion tests on twelve (12) patients who had been on haemodialysis for less than one year (mean 8 months) and had normal serum aluminium levels. The patients had no bone symptoms. Eight patients had positive aluminium bone stains. The aluminium osteomalacia group (n = 8) had a mean PTH of 1.4 ng/ml s.e. 0.3 whereas the non-ALO group had a mean PTH of 2.9 ng/ml s.e. 0.7. The difference in mean PTH is significant (p less than 0.05). There was no evidence of encephalopathy, fractures or microcytic anaemia in the ALO positive group. The aluminium contamination of the water supply occurred because of a change in the reservoir purification system from sand-filtration to alum.

The distribution of melanin pigment-containing cells in the bones of both young and adult silky fowls was observed. Melanin pigment was detected not only in melanocytes which were mainly distributed in the periosteum, but also in all the other types of cells in the periosteum and bone. The continuity of the number of pigment granules in melanocytes and that in the other pigment-containing cells could not be recognized because the granules in the latter cells were much fewer than those in the former. In young fowls, the pigment-containing cells were distributed in all layers of the periosteum and bone, but their number was low. On the other hand, in aged fowls, most of the cells in the periosteum had pigment granules. In the bone, however, pigment granules were observed only in osteocyte situated near the surface. These findings suggest that the pigment granules which are observed in osteocytes have been transferred from melanocytes to osteogenic cells or osteoblasts before they differentiate to osteocytes, where they are presumed to be digested.

Elongation of fetal chick long bone rudiments is formed by a mitogenic activity from porcine bone in vitro. Fractions of mitogenic activity from a heat- and acid-treated extract and from sequential chromatography on hydroxyapatite and from gel-filtration in 4 M guanidine-HCl increase diaphyseal elongation of metatarsals. The bone elongation-forming activity is associated with the mitogenic activity estimated by the incorporation of [3H]-methyl thymidine into the DNA of cells from embryonic chick periosteum. Histological examination of the mitogen-treated embryonic chick long bone shows that the partially purified fractions with a preferential effect on osteogenic cells increase diaphyseal elongation via cartilage cell proliferation.

Bone morphogenetic protein (BMP) was extracted from bone matrix, dentin matrix, and wound tissue after tooth extraction in rabbits, and purified. These purified fractions were shown to be homogeneous by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis (SDS-PAGE), and induced new bone in situ in 3 weeks when implanted into the calf muscles of Wistar rats. The dentin matrix-derived BMP was different from the other two types in molecular weight and the properties revealed in the process of purification. However, each tissue-derived BMP was shown to induce new bone growth in a bioassay of xenogenic implantation. For this reason, BMP is thought to have subunits with certain commonalities in different tissue.

During the past two decades, some major pitfalls in fluorine analysis have been recognized and overcome. Therefore, it is important that facts be separated from fallacies in published literature on levels and forms of fluorine (ionic, bound, covalent, etc.) in biological materials, in order that correct perceptions of physiological, biochemical, and toxicological aspects of inorganic as well as organic fluorine compounds can be formed. Trace amounts of inorganic fluoride in biological samples can now be accurately determined with the fluoride electrode either directly or following diffusion, adsorption, or reverse extraction of fluoride (when necessary). The aluminum monofluoride molecular absorption technique provides an excellent rapid method for determination of trace amounts of inorganic fluoride (in the absence of organic fluorine). Fluorine in most organic fluorine compounds is not available for distillation, diffusion, or reverse-extraction. The sample needs to be ashed (open ashing) or combusted (oxygen flask, oxygen bomb, pyrohydrolysis) for covalently bound fluorine to be converted to fluoride ions. This can now be readily accomplished at room temperature by the reductive cleavage of the C-F bond with the sodium biphenyl reagent. Some recommendations for future research have been made.

Optimal conditions for storage of calcified tissues prior to lipid analysis were determined by comparing the lipid composition (total lipid, total phospholipid, triglyceride, free fatty acid, cholesterol, and complexed acidic phospholipid) of mature rabbit diaphyseal bone stored 1, 2, and 5 months after animal sacrifice to that observed in the bones from which the lipids were immediately extracted at the time of sacrifice. Storage of lyophilized or nonlyophilized tissues at -70 degrees, or lyophilized tissues at -20 degrees, were the only methods that did not yield significant changes in bone lipid composition with time.

A cDNA encoding osteonectin was isolated from a human bone cell cDNA library and used to examine osteonectin protein structure, mRNA structure and expression in human tissue. The deduced protein sequence shows complete identity with a recently isolated placental form and extensive homology to mouse and bovine counterparts. The protein is rich in cysteine residues, which are conserved between species except for cys 194 which is only present in the bovine. In the human, osteonectin mRNA is of two sizes, 2.3 and 3.0 kb, the former being dominant in all tissues studied. Human mRNA was detected in the Ewing sarcoma and in non-bone cell and tissue sources. The potential folded structure of osteonectin mRNA was estimated, based on computer predictions, and indicates the presence of a bulge at the 5' end of the message which includes the start of translation. Southern analysis of human genomic DNA using radiolabeled osteonectin cDNA as probe demonstrates a simple banding pattern confirming earlier studies that the osteonectin gene is present in one copy per haploid human genome.

Bone samples were obtained from 65 Beijing residents who had died from illness or old age. The concentration of uranium in the bone ash was determined by the laser-fluorimetric method. The concentration varied between 0.014 and 0.390 microgram g-1 ash, with a median value of 0.067 microgram g-1 ash; the 25th and 75th percentiles were 0.045 and 0.1 microgram g-1 ash respectively. The arithmetic mean was 0.083 microgram g-1 ash. The concentration of uranium in bone (ash) correlated with age, but not with sex; uranium participates in the bone calcification process.

A method for decalcification end point determination of mineralized tissue is described. The calcium content of the decalcification solution was determined colorimetrically with a "continuous automatic analyzer" with a high degree of accuracy. The end point method used has been tested on two decalcification methods, 5% nitric acid with or without ultrasonic treatment. The results suggest it is possible to quantitate the decalcification process.

The role of oyster shell as calcium supplement in the utilization of gossypol-containing cottonseed cake (CSC) was assessed using Hypeco broiler chickens. The results showed that of the organ measured, only the relative weight of the spleen was significantly (P less than 0.05) decreased by oyster shell supplementation in the CSC diets. Spleen weight correlated negatively (r = -0.45) with dietary calcium. Alkaline phosphatase activity in the liver was significantly (P less than 0.05) increased due to the levels of oyster shell supplemented while the activities of serum and liver alanine aminotransferase and aspartate aminotransferase were not significantly influenced. The results also showed that although oyster shell supplementation generally increased alkaline phosphatase activity, bone mineralization was relatively uninfluenced as judged by the low coefficients of variation (CV) of 3.14-3.51% and 3.39-4.82% for calcium and phosphorus content in the femur and tibia respectively.

Quantitative computed tomography (QCT) was used to assess trabecular bone mineral concentration in the vertebrae of 132 children, 45 with suspected disorder of bone mineralisation, 54 with thalassaemia and 37 controls. The range for bone mineral concentration in controls, expressed as equivalent K2HPO4 concentrations, was 90-190 mg cm-3. Abnormally low values were seen in all untreated children with idiopathic juvenile osteoporosis, 3/9 steroid recipients, and three patients with osteogenesis imperfecta. Abnormally high values were seen in 10/14 chronic renal failure patients. Comparison of the single and dual-energy methods showed that the single energy method, which has a lower radiation dose and is less prone to error from movement artifact, is satisfactory in most paediatric applications.

Feeding habits of free-ranging martens (Martes martes and Martes foina) are evaluated by means of trace element and stable carbon isotope analyses of their skeletons. This investigation was carried out as an inter-disciplinary project of both wildlife biology and physical anthropology. As a result, data are obtained on the feeding ecology of the two species; in addition, a baseline is provided for dietary reconstruction of past human populations. Both species of martens are omnivorous feeders, M. martes being slightly more carnivorous than M. foina. Diversity of dietary intake with respect to plant food and animal protein is only one-third of the maximum divergence between strict herbivores and carnivores.